Mean follow up was 26 months. Clinical outcome was significantly better for flexion degrees following screw fixation (p = 0.009). Delayed fracture union (p = 0.002) or non-union (p = 0.006) rates were significantly higher in plate osteosynthesis. Mild pathologic deformity for varus and valgus collapse was found following plate osteosynthesis. Conclusions: Screw fixation shows fewer postoperative complications than plate fixation and is favored for extra and partial intraarticular distal femur fractures. Plating constructs remain the superior fixation method in complex distal femur fractures but are associated with higher rates of non-union and leg axis deviation.Background: Distal femur fractures are challenging in surgical management as the outcome is crucial for restoring the biomechanical stability and longitudinal axis of the leg and function of the knee joint. Methods: A retrospective review of all distal femoral fractures treated in a level I trauma center over a decade was performed. The radiographs were reviewed for fracture entity, osseous healing, implant failure, mechanical axis, and degenerative joint changes. Clinical outcome was reviewed regarding postoperative complications and postoperative range of motion of the knee joint. Results: 130 patients who were managed with screw fixation ( Fractures of the femur represent about 3–6% of all musculoskeletal injuries, with the distal femur being involved in about 1% of all cases . The incSince the distal femur plays a crucial part in the biomechanical functionality of the knee joint, in addition to in the longitudinal axis stability of the leg, the surgical treatment of these fractures is vital for the mobilization and resilience of the patient. Common deformities in distal femur fractures include shortening, flexion and external rotation of the proximal fragments, and the extension of the distal fragments. These issues are the result of powerful muscles, such as the gastrocnemius and the adductor muscle, which insert on and exert unilateral forces on the distal femur .With the expected dynamic demographic change and the more active lifestyle of older people, it is likely that injuries to the distal femur will increase as well. Non-operative treatment achieved acceptable results back in the early 1960s . During Some fracture types are suitable for surgical treatment with an intramedullary force carrier. The improvement of the nail design with a retrograde knee insertion point has given this procedure a relevant status. Biomechanically, the intramedullary nail shows greater axial stability and fewer micromovements compared to dynamic condyle screws and locking condyle plates . HoweverThe aim of the retrospective cohort study is the critical analysis of clinical and radiographic outcome of different surgical methods in the management of distal femoral fractures. The comparison of different osteosynthesis procedures based on the incidence of postoperative complications allows a prediction of better treatment methods.To our knowledge, isolated small or large fragment screw fixation, except in the management of Hoffa fractures, has not yet been further evaluated. We also aim to clarify which surgical approach has the fewest complications for the surrounding tissue and the patient and the potential postoperative deviation of the longitudinal femur axis. In addition, it should also be investigated whether intraarticular fracture involvement has a relevant influence on the development of posttraumatic degenerative changes to the knee joint.The clinical database of a level I trauma center was searched for surgically managed distal femoral fractures using the postoperative diagnosis variable codes S72.40–S72.44 ). The data acquisition period was over 10 years between 1 January 2010 and 31 December 2020. Inclusion criteria for this retrospective cohort study were complete clinical and radiographic patient charts, surgically managed fractures using plating system, screws, or intramedullary nail, patient’s age at time of surgery > 18, and postoperative follow up at the outpatient clinic of a minimum of 3 months. Exclusion criteria were juvenile fractures and periprosthetic and pathological fractures.Each patient record was reviewed for patient factors (gender and age) and comorbidities , injury-related factors (soft tissue damage according to the Gustilo–Anderson classification ), the frp-value < 0.05 was considered to indicate statistical significance. Due to the exploratory character of the study, no correction was made for multiple testing; calculated p-values are purely descriptive.Statistical analysis was performed with OriginPro, version 2023 . Due to non-normal distribution of the values, a nonparametric test was used. For continuous values, Kruskal–Wallis ANOVA was used with Dunn’s test for comparison of more than 2 groups. For ordinal data, the chi-square test was used. A The study protocol was approved by the local Human Research Ethics Committee of the Albert Ludwig University of Freiburg, ethical approval code: 22-1287-S1-retro.Within the data acquisition period of 10 years (2010–2020), 520 patients were identified who sustained distal femoral fractures. Considering the specific inclusion criteria, 130 patients remained for the retrospective data analysis .There were 71 male patients and 59 female patients; mean age at the time of surgery was 52.3 ± 20.5. Mean follow up was 25.8 months (3–170 months) in this study cohort. Relevant comorbidities were found in 92/130 included patients. There were 29 patients suffering from a bone metabolism disorder such as osteoporosis or osteopenia, 17 had a cardiovascular history, 14 had obesity defined by a BMI > 35, 11 had a diabetic history, and 6 were smokers. However, a statistical significance between the primary union group and the non-union group for those with a bone metabolism disorder was recorded .The included patients were allocated to groups with respect to the surgical management: screw fixation using either small or large fragment screws , variable angle plate or locking vs. non-locking plate osteosynthesis , or intramedullary nailing system  .Hence, statistical analysis was carried out between groups 1 and 2. Three patients in group 1 sustained bilateral distal femoral fractures; 13 bilateral distal femoral fracture injuries were found in group 2. A tabular overview of demographic data, fracture entities, and postoperative complications is given in In group 2, the LISS plate  was used in 78 patients; 10 patients were managed using a VA-LCP; a T-shaped LCP was used in two patients; one patient received an NCB ; and one patient received a TomoFix plate . Combined fracture management using a plate system and additional fragment screw fixation was performed in 73 out of 92 patients (80%).p < 0.0001), were significantly more often managed with plating systems. Partial articular distal femoral fractures, as well as unilateral condyle fractures, were predominantly fixed with screws. Further sub-analysis of the correlation between the fracture entity and fracture union was performed for group 2 as the included number of patients allowed statistical analysis. Wound healing disorder during the early postoperative course was significantly more often seen following AO type 33C2 and C3 (p = 0.032). Osseous non-union > 9 months post-surgery was higher in AO fracture type 33C1-3 (p = 0.049)  .p = 0.022). Early postoperative complications such as wound healing problems, wound infection, or thromboembolism did not show any significance between groups (p = 0.002). Fracture non-union >9 months postoperatively was found significantly more often following plate osteosynthesis (p = 0.006), 25 patients in group 2 versus one patient in group 1. The osseous non-union rate during the early postoperative course of 6 weeks was significantly higher in group 2 (p = 0.023); further follow up showed no significant differences in the bony healing phase between the examined groups, with completed osseous healing at latest follow-up >2 years , with patients aged 31–50 years tending to experience osseous non-union; second, the soft tissue damage was significant for the bony healing (p = 0.027); and, third, bacterial infection to the soft tissue occurred during the postoperative course (p = 0.001). Seven of twenty-five patients were affected with infectious osseous non-union. In all cases, soft tissue damage of Gustillo–Anderson classification grade 2 or higher was documented. This was managed with complete removal of the plating system and hybrid external fixation system and revision surgery after secured restoration of the infection. Two of these patients received an additional fibula graft. Osseous healing was achieved within 16 months (12–30 months) post-revision-surgery. An atrophic osseous non-union was found in 15 patients; these patients were managed with revision plate surgery and additive cancellous bone. Osseous healing was completed after a mean of 12 months (8–16 months). Three other patients affected with atrophic non-union were managed with exogen therapy.A detailed review of osseous union versus non-union in group 2 showed that, first, the patient’s age had a significant influence on the osseous healing (p > 0.999 between groups and p = 0.595 for union vs. non-union rate in plate group).The surgical approach was chosen depending on the choice of implant. When using plating systems, the anterolateral approach was the most common (71/92 patients). Parapatellar and medial, but also percutaneous accesses, were chosen most frequently for screw osteosynthesis. The surgical approach did not show any impact on the complication rate (p = 0.009), with flexion rates of 122.50 ± 14.64 degrees vs. 104.74 ± 26.12 in group 2 (Postoperative degenerative joint changes according to the Kellgren–Lawrence classification  showed a group 2 .p = 0.002).There was no knee flexion deficit for the range of motion <90° in either group, but there was a loss of extension >10° in 6 of 57 patients with the available data in group 2 at the latest follow up. Implant malalignment, defined as loss of the bony contact surface to the plate or incorrect positioning of the screws, was documented significantly more often in group 2 . The analysis of the mechanical leg axis showed no statistically significant differences between groups, but mild or pathologic deformities were found more often in group 2 compared to in group 1  reviewed patients with available data in the plating group, as well as a mild valgus collapse in 15/25 (60%) patients in the same group without any significance between groups. Four out of sixty-five patients in group 2 had a pathologic leg length discrepancy of >1.5 cm at the latest follow up.The aim of the presented retrospective cohort study was to determine the clinical and radiographic long-term outcome of different methods of surgical management of distal femur fractures. Simple extraarticular or partial intraarticular distal femoral fractures were predominantly fixed with screws with evidently fewer postoperative complications. The clinical outcome was significantly better for the postoperative range of flexion degrees after screw fixation. Osseous union was completed earlier after screw osteosynthesis. Delayed osseous union and non-union rates were affected by the patient’s age, the sustained soft tissue damage, and infection during the postoperative course, as well as comminuted fracture types. Mild pathological changes affecting the longitudinal axis of the leg were found in 28% with varus collapse and 60% with valgus collapse after surgical fracture treatment with plate systems. The chosen surgical approach had no impact on the postoperative course regarding infection or implant misalignment. Posttraumatic degenerative changes with radiographic changes showed a progression in each reviewed group without statistical significance.Two-step surgery with initial placement of an external fixator was significantly more often performed prior to definite plate fixation of distal femur fractures. These, in turn, were used more frequently in complex intraarticular AO 33C1-3 distal femoral fractures. Further sub-analysis of the fracture entity showed that comminuted fracture types AO 33C2 and C3 significantly more often had wound healing problems during the early postoperative course.The indication for intramedullary nail or plate fixation in fracture management of distal femur fractures is dependent on many factors: the degree of comminution, coronal plane involvement, bone quality, and distal extent of the fracture. As predominantly intraarticular distal femur fractures were reviewed in the presented study, the indication for fracture management using an intramedullary nailing system was very limited. The fixation of distal femur fractures using screws only was most frequently discussed following unicondylar fracture types. In our cohort, only 10 patients had a defined Hoffa fracture type entity AO 33B3.2.Only a few studies were available for direct comparison with the presented findings.A retrospective cohort study with 116 patients with a mean follow up of 11 years showed that functional outcomes, as well as postoperative complication rates, were significantly superior following condylar screw fixation compared to following plate fixation . In a smA biomechanical analysis of distal femur fracture fixation in a human cadaveric study showed that axial stiffness and cyclic loading were significant higher following locked compression plate fixation, but no differences were found in torsional stiffness between locked compression plate fixation and dynamic condylar screw fixation . AnotherDual plating of distal femur fractures has gained more attention for preventing varus collapse and implant failure in comminuted metaphyseal and articular fractures. In a systematic review, satisfactory results were found for comminuted metaphyseal and articular fractures following dual plating, but no differences were found between single lateral plating and dual plating with regards to non-union rate, blood loss, functional outcomes, and complications, although dual plating led to faster fracture healing . A largeTwo meta-analyses have been published recently that specifically reviewed the occurrence of improper healing and reoperations after different techniques for the surgical stabilization of distal femoral fractures ,28. BothMore pragmatic surgical treatment approaches have been discussed in the recent past. The management of open type C3 distal femur fractures with primary definitive fixation with a condylar locking plate and an antibiotic-impregnated collagen sheet showed better results in terms of functional and radiological outcomes . AnotherThe presented results are in accordance with other published data. Screw fixation had superior knee function results at the latest follow up; an extension deficit of >10° was found in 10% (6/57 patients with available data) following plate osteosynthesis. Neither the surgical approach in general nor minimal invasive surgical fixation methods had an impact on postoperative complications. Posttraumatic degenerative joint changes of the affected knee were observed without any significance in occurrence or progression between the reviewed groups. Osseous union rates showed a significant superiority for screw fixation. This information is with respect to less complex fracture entities and less soft tissue damage.To our knowledge, a specific review of potential changes of the longitudinal femur axis has not yet been presented. Those patients who achieved a long leg radiographic examination at the latest follow up showed a mild pathologic varus collapse of 91–96° in 28% and valgus collapse of 73–78° in 60% of cases following plate osteosynthesis but without statistical significance.There were some limitations to this study that deserve consideration. The retrospective character of the study limited the precision of the data and means that all surgical treatments and chosen implants were at the discretion of the operating surgeon. The nature of a single-center study limited the achievable data as well. Respecting the eligibility of inclusion criteria led to a high number of excluded patients. As distal shaft fractures were excluded from the presented cohort study, the number of patients who were managed with an intramedullary nailing system was low and could not be considered for statistical analysis. The group size of patients managed with plating systems was almost three times larger than the comparison group of screw fixation. Hence, the statistical outcome was critical to discuss and allowed clinical relevance rather than statistical relevance. Additionally, although we found multiple independent variables that predicted healing complications, such as soft tissue damage or patient’s age, multiple independent variables that predict healing complications were not analyzed .The results of the retrospective cohort study show that fewer complex distal femoral fractures are suitable for screw fixation with superior functional results and a better radiographic long-term outcome. For comminuted distal intraarticular femur fractures, plating systems remain the preferred treatment method, although predictable and non-predictable outcome factors are known. Comminuted distal femur fractures, patient’s age, soft tissue damage, and early wound healing problems are risk factors for osseous non-union. Valgus collapse is a relevant risk factor following plating constructs. Current, available data are consistent in the outcome of plating systems but inconsistent in comparison of contemporary treatment options. Further randomized, controlled trials including patient-related functional outcomes are missing to define evidence-based results.


Cell fate transition is a fascinating process involving complex dynamics of three-dimensional (3D) chromatin organization and phase separation, which play an essential role in cell fate decision by regulating gene expression. Phase separation is increasingly being considered a driving force of chromatin folding. In this review, we have summarized the dynamic features of 3D chromatin and phase separation during physiological and pathological cell fate transitions and systematically analyzed recent evidence of phase separation facilitating the chromatin structure. In addition, we discuss current advances in understanding how phase separation contributes to physical and functional enhancer-promoter contacts. We highlight the functional roles of 3D chromatin organization and phase separation in cell fate transitions, and more explorations are required to study the regulatory relationship between 3D chromatin organization and phase separation.3D chromatin organization (shown by Hi-C contact map) and phase separation are highly dynamic and play functional roles during early embryonic development, cell differentiation, somatic reprogramming, cell transdifferentiation and pathogenetic process. Phase separation can regulate 3D chromatin organization directly, but whether 3D chromatin organization regulates phase separation remains unclear. Cell fate transitions are a set of important biological processes in multicellular organisms that determine the functions of different cell types. Numerous molecular mechanisms are associated with cell fate regulation, such as epigenetic landscape remodeling, 3D chromatin reorganization, and phase separation  Different chromatin architecture associating factors are required. The cohesin complex and CTCF are important structural factors regulating TAD establishment through loop extrusion during human embryogenesis , and histone locus bodies (HLBs), also undergo dynamics during early embryogenesis. Nucleolus is the nuclear compartment of rRNA transcription and processing, as well as ribosomal assembly  and human embryonic lung fibroblasts (IMR90)   to induced pluripotency stem cells (iPSCs), 25% of the compartments show frequent switching, including 14% B-A switching, 5% A-B switching, and 6% unstable switching   is a fundamental biological process occurred in aging, embryonic development, and tumor suppression , which are specialized domains of facultative heterochromatin formed in senescent cells , including deletions, insertions, duplications, and translocations   in haplo-insufficient human iPSC models of LMNA-related DCM. Redistributed LADs were associated with increased CpG methylation and gene repression, although A/B compartment switching occurred in only 1% of the genome  of compartments eventually undergoes switching  Point mutations or structural variations in enhancers or target genes, (2) structural variations at chromatin structural factor-binding sites, and (3) mutations of chromatin structural factors or other regulatory proteins. The underlying mechanisms of compartment switching in disease are still not fully understood. Phase separation has been proposed to facilitate compartment formation  artificially induce liquid condensates at specific genomic loci to observe 3D chromatin alterations  within PcG bodies  protein CBX2 is able to undergo phase separation and may be the driver for PRC1 to form liquid condensates , suggesting that BRD4 may be involved in 3D chromatin folding through liquid-liquid phase separation  may also regulate 3D chromatin organization in a similar way. More direct evidence is required to validate the causal relationship between phase separation and 3D chromatin organization.Cell fate transitions are accompanied by dynamics of 3D chromatin organization and phase separation, and nuclear condensates can directly facilitate 3D chromatin organization. However, the complexity of chromatin folding is far beyond imagination since different regulatory mechanisms exist at the same time. There is a long-standing controversy over the functional roles of phase separation in enhancer-promoter interaction establishment and maintenance. By regulating cell type-specific gene expression, phase separation and 3D chromatin organization can concomitantly or independently affect cell fate transitions.Phase separations, including LLPS and PPPS, provide new insights into how chromatin is folded into complicated but mostly distinct structures at different hierarchies in the nucleus. Loop extrusion is the typical mechanism directly mediating chromatin looping by SMC complexes and CTCF. There are probably some unknown possibilities to explain chromatin folding, since cellular condensation can result from other mechanisms distinct from phase separation. One study found that recruitment of RNA Pol II and other factors to replication compartments is predominantly dependent on transient and non-specific binding to DNA during viral infection  PhaThere are still many enigmatic questions remained to be answered. How nuclear condensates  are organized exactly? What molecular events related to 3D chromatin organization happen in or around these condensates in vivo? How do these nuclear condensates change accompanied with 3D chromatin reorganization during cell fate transitions?More and more studies are focusing on whether phase separation is involved in 3D chromatin regulation currently, but it remains to be determined as to why regulators undergo LLPS to exert their functions. The possible functions of LLPS include to facilitate cellular activities by sequestering distinctive molecules and forming relatively-independent microenvironments, and to buffer the effective condensation of other cellular molecules. Further investigations are needed to elucidate the role of 3D chromatin organization in phase separation modulation, and new methods have to be developed to unravel the relationship between 3D chromatin and phase separation.


Lilium lancifolium Thunb.) is a cash crop with a long history of cultivation in China. Its roots have long been used as a valuable component of Chinese medicine. Continuous cropping, the conventional planting approach for tiger lily, often leads to severe root rot disease, but it is not yet clear how this planting method leads to root rot. In this study, we analyzed the rhizosphere microbiome and predicted microbial protein function in tiger lily planted with the continuous cropping method in three different geological types of soil. In order to explore the specific rhizosphere microbiota triggering root rot disease, tiger lily was compared to maize grown in a similar system, which showed no disease development. An analysis of the chemical elements in the soil revealed that the Pseudomonas and Streptomyces genera, with pathogenic functions, were dominant in the tiger lily rhizosphere. The lower soil pH of tiger lily compared to maize supports the accumulation of pathogenic bacteria in the tiger lily rhizosphere. Meanwhile, we discovered that bacteria of the Flavobacterium genus, with their predicted phosphate transport function, specifically accumulated in the maize rhizosphere. Our findings suggest that Pseudomonas and Streptomyces bacteria may result in continuous cropping–induced root rot disease in tiger lily and that Flavobacterium could serve to protect maize from pathogenic bacteria.Tiger lily ( There is a close relationship between plants and the microbiota populating their roots and the surrounding soil, particularly the rhizosphere, where microbes transport nutrients released from the plant’s roots . RhizospFusarium graminearum attack by altering the composition of the rhizospheric bacterial community. Similarly, an abundance of bacteria from the Acidobacteria phylum and the Pseudomonas and Chthonomonas genera has been implicated in the suppression of fusarium wilt disease in banana  and tiger lily (Lilium lancifolium Thunb.) were obtained from Longyan Seeds Resource Center and Longyan Xiluo Supply and Marketing Cooperator, respectively. Maize seeds were stratified at 4°C for 48 h, then sterilized with 30% house bleach for 10 min, followed by five times washing in sterile double-distilled water. Tiger lily was directly cultured by bud cutting. The maize seeds (225 seedlings per area 5 × 5 m) and tiger lily bud cuttings (250 seedlings per area 5 × 5 m) were planted on Cambrian, Ordovician, and Silurian soil in Xiangxi prefecture  under open natural conditions. Both the maize and tiger lily were planted continuously three times prior to sample collection; samples were collected after the third round of cultivation. After plantation in the soil, maize and tiger lily were grown continuously for 156 days (measuring stage), at which point the rhizosphere samples were collected for 16S rRNA gene sequencing. During growth, both maize and lily were cultivated with no fertilizers or other herbicides, and underwent weeding, plowing, and watering 2–3 times.Maize (2 area to avoid any bias caused by uneven soil conditions) grown on one soil type was collected as one biological replicate. Four biological replicates of each sample were prepared for DNA extraction. Detailed information on the samples is available in Microbiome samples were collected based on previous publications . Briefly® SPIN Kit for Soil  following the manufacturer’s instructions. Microbiome DNA samples were eluted in 100 μl nuclease-free water and DNA concentrations were determined by using Nanodrop 2000 . The amplicon libraries were generated following the protocol of the Illumina Novaseq System for 16S rRNA gene metagenomic sequencing library preparation. Two rounds of polymerase chain reaction (PCR) were performed with the KAPA HiFi HotStart ReadyMix. The first-round PCR primers 799F (5′-AACMGGATTAGATACCCKG-3′) and 1193R (5′-ACGTCATCCCCACCTTCC-3′), which span ∼400 bp of the hypervariable regions V5–V7 of the prokaryotic 16S rRNA gene, were extended to 799F–B and 1193R–B by adding bridging sequences (5′-ggagtgagtacggtgtgc-3′ and 5′-gagttggatgctggatgg-3′) at their 5′ ends to better facilitate the second round of PCR. For each biological replicate, three technical replicates were conducted to increase the final amount. The PCR was conducted on a 96-well plate with the KAPA HiFi HotStart ReadyMix by using 2 μl of 8 ng/μl adjusted DNA template in a total volume of 25 μl, with 1 μl of 5 μM of each primer.DNA sample preparation and 16S rRNA gene sequencing were performed as previously described , with miThe first PCR reaction was performed as follows: initial denaturing at 95°C for 3 min, followed by 30 cycles of 95°C for 30 s, 55°C for 30 s, 72°C for 30 s, and extension at 72°C for 5 min. Triplicate reactions of each sample were pooled and a 15 μl aliquot was loaded on a 1% agarose gel. The PCR primers 799F and 1193R produce a mitochondrial product at ∼800 bp and a bacterial amplicon at ∼400 bp. The ∼400 bp bands were extracted from the gel with a sharp scalpel and eluted from the agarose using the QIAquick Gel Extraction kit  as per the manufacturer’s protocol. After purification and elution in 80 μl nuclease-free water, the concentration of the amplicon DNA of each sample was determined by using the dsDNA HS Assay Kit  on Qubit 2.0 . The first-round PCR products were further barcoded during the second-round PCR following the protocol of the Illumina Novaseq System for the 16S rRNA gene metagenomic sequencing library preparation.The second PCR amplification was conducted on a 96-well plate in 20 μl volume containing 4 μg first-round PCR products, 20 nM unique barcode primers see , and 2001  to detect and remove chimeras .The 16S rRNA gene sequencing data analysis was performed as previously described . Raw Tag1 . High-quchimeras . After tsoftware . Sequencd QIIME2 . A minimd QIIME2 . The wei2The protein function prediction analysis was conducted using PICRUSt2 software with the KEGG Orthology (KO) metagenome database. Heatmaps were created using the iDEP.90 online tool.The soil of the rhizosphere samples used for 16S rRNA gene sequencing was also used for soil characteristics identification. Elemental silver (Ag) was determined by spectral lines with different sensitivity of alternating current arc emission spectroscopy (ES). Mercury (Hg) was determined by atomic fluorescence spectroscopy (AFS 8500). Iron (Fe) and phosphorus (P) were analyzed by inductively coupled plasma optical emission spectroscopy . Nitrogen (N) was determined by elemental analyzer (EA 5100). The pH of different soil samples was determined by the ion-selective electrode  method. Organic compounds were determined with the titration method of ferrous sulfate and potassium dichromate sulfuric acid.p-value ≤ 0.05, indicated statistical significance between different samples. Student’s t-test was used for statistical significance analysis of soil characteristics with six biological replicates of each sample.One-way ANOVA with Tukey’s multiple comparison test, the Kruskal–Wallis test, and an ANOSIM assay were used for the statistical analysis of data in this study. Four biological replicates of each sample, with a In order to explore the reasons for root rot in tiger lily caused by continuous cropping, we conducted 16S rRNA gene sequencing to identify the microbiota using six rhizosphere samples. We described them with the following terms: Clily (tiger lily rhizosphere samples from Cambrian soil); Cmaize (maize rhizosphere samples from Cambrian soil); Olily (tiger lily rhizosphere samples from Ordovician soil); Omaize (maize rhizosphere samples from Ordovician soil); Slily (tiger lily rhizosphere samples from Silurian soil); Smaize (maize rhizosphere samples from Silurian soil). Maize, a major crop cultivated under similar conditions as tiger lily but without suffering from the same root rot disease, was selected as a parallel plant to better explore which candidate pathogenic bacteria are specifically associated with tiger lily. The plants were grown in the fields of Xiangxi prefecture, as described in the Section “Materials and methods.”The hypervariable regions of V5–V7 in the prokaryotic 16S rRNA gene were amplified for the preparation of sequencing libraries. A total of 10,554 unique amplicon species variates (ASVs) were identified from all samples . After cSequence quality was measured by the paired-sequence combination rate with a minimum of 16 bp overlapped length among samples. More than 82% of the sequences of each sample were highly qualified see . PrincipWe also performed an alpha diversity assay in order to investigate the taxonomic diversity in different samples. A boxplot of the alpha diversity indicated significant differences in the distance between samples see . The totSediminicola as the most abundant species in Clily  among different soil types  database. Principal component analysis (PCA) of the bacterial function KO terms showed a clear separation between maize and tiger lily among different soil types . We nextProteobacteria phyla and 30% of the Actinobacteriota phyla make up the main bacterial community among the 23 KOs [for Proteobacteria, 59.6% of the bacteria are of the Gammaproteobacteria class  conditions for pathogenic bacteria  and 12% , respectively, of the ASVs of pathogenesis-related functional terms were function . Howeverzosphere . They hazosphere .Fusarium oxysporum caused lily root disease through vascular wilt. Although P. marginalis was one of the reasons for soft rot disease in lily, the supporting evidence is limited. In this study, we explored various genera by using rhizomicrobiota and predicted protein function, and we found Pseudomonas and Streptomyces to be the major candidates likely responsible for root rot disease. However, the specific pathogenic strains accumulated in the tiger lily rhizosphere, and their pathogenic mechanisms, are not clear.Synthetic microbial communities (SynCom) has been reported as a highly reproducible tool for investigating the relationship between plants and bacteria . Follow-Flavobacterium mainly accumulates in the maize rhizosphere, relative to that of tiger lily. Functional prediction of the maize microbiome indicated that Flavobacterium has a phosphate transport ability. As has been shown previously, most of the Flavobacterium genus can be used as plant growth–promoting bacteria thanks to their properties of phosphate solubilization and auxin and siderophore production (Flavobacterium genus is markedly higher in Silurian soil compared to Cambrian and Ordovician soils, indicating that maize may achieve higher biomass in Silurian soil. However, from a practical standpoint, crop biomass is affected by environmental factors apart from rhizosphere microbiota, and there is no clear record of differences in maize biomass among the three geological soils studied here.Our findings also reveal that oduction . A dominoduction , which mFlavobacterium genus, with its phosphate transport function, is the major beneficial genus for the growth of healthy maize in Silurian soil. Pseudomonas and Streptomyces bacteria, with their pathogenic function enriched in the tiger lily rhizosphere, may result in root rot disease under the continuous cropping method.In conclusion, the composition of the rhizosphere microbiome plays important roles in crop cultivation and disease monitoring. We demonstrated the intrinsic differences in the rhizosphere microbiota between tiger lily and maize in three geological soil types: Ordovician, Silurian, and Cambrian soil. Our work revealed that the PRJNA816815, and BioSample ID: SAMN26733807.The datasets presented in this study can be found in online repositories. The 16S rRNA gene sequencing data is available in the NCBI SRA under BioProject SS and DW edited the languages and corrected typos. All authors contributed to the article and approved the submitted version.


To the Editors,We greatly appreciate the comments by Dr. Finsterer on our previous article describing patients who showed cytotoxic lesions of the corpus callosum (CLOCCs) after coronavirus disease 2019 (COVID-19) messenger ribonucleic acid (mRNA) vaccination, which provided us an opportunity to describe diagnostic strategies for neurological symptoms and to provide further information on Patient 2 [Regarding the first criticism on our description that side effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinations are not life-threatening, we would like to clarify that this notion is derived from previous studies which evaluated neurological adverse events among healthcare workers after COVID-19 mRNA vaccination , 4. The 1 was 39 ng/mL  and vitamin B12 was 218 pg/mL  on day 17. CLOCCs are defined as highly restricted ovoid lesions in the midline of the splenium as shown in our patients [As for the second criticism on insufficient investigation of Patient 2, we apologize for providing wrong information in the previous manuscript . In contAdmitting that precise diagnostic procedure is crucial and therapeutic intervention should be based on the most plausible diagnosis, full establishment of diagnosis requires at least several weeks, causes delay in treatment, and directly affects prognosis of patients in clinical practice. Correlation between radiological characteristics of lesions involving the corpus callosum including CLOCCs and various neurological disorders will enable us to establish diagnostic and therapeutic strategies from etiological point of view.


A pattern of pronounced climatic cyclicity transformed habitats during episodes 7–9 , a crucial phase encompassing the gradual transition from Acheulean to Middle Stone Age technologies, the emergence of Homo sapiens in eastern Africa and key human social and cultural innovations. Those accumulative innovations plus the alignment of humid pulses between northeastern Africa and the eastern Mediterranean during high-frequency climate oscillations of episodes 10–12  could have facilitated the global dispersal of H. sapiens.Despite more than half a century of hominin fossil discoveries in eastern Africa, the regional environmental context of hominin evolution and dispersal is not well established due to the lack of continuous palaeoenvironmental records from one of the proven habitats of early human populations, particularly for the Pleistocene epoch. Here we present a 620,000-year environmental record from Chew Bahir, southern Ethiopia, which is proximal to key fossil sites. Our record documents the potential influence of different episodes of climatic variability on hominin biological and cultural transformation. The appearance of high anatomical diversity in hominin groups coincides with long-lasting and relatively stable humid conditions from ~620,000 to 275,000 years  Over the past 620,000 years, three distinct phases of climate variability in eastern Africa coincided with shifts in hominin evolution and dispersal, according to an analysis of environmental proxy records from a core collected in the Chew Bahir basin of Ethiopia. Hypotheses seeking to explain links between climate and human origins are difficult to test because both climate records and traces of early human populations are often incomplete or poorly dated5. Encouraged by discussion of possible climate-evolution linkages, the Hominin Sites and Paleolakes Drilling Project (HSPDP) was established in 2008, with deep drilling campaigns in 2013–20146. One component of HSPDP, the Chew Bahir Drilling Project (CBDP), collected two ~280-m-long cores from Chew Bahir (CHB), a playa lake in southern Ethiopia  9, which includes the time frame of the emergence of H. sapiens in Africa11. While there is a general consensus that the physical, cognitive and cultural evolution of H. sapiens in Africa developed multiregionally12, the CHB record provides an environmental window with which to view the eastern African part of this history6. The CHB coring site is situated near key archaeological and palaeoanthropological sites, such as the Omo-Kibish (~90 km west of CHB)  of palaeolake and pore waters, which in a closed lake basin corresponds to changes in water depth16. High K in CHB, fostered by an increase in alkalinity and salinity under lowering lake levels during dry climate episodes, is further enhanced by octahedral Al-to-Mg substitutions in clay minerals and a resulting layer charge increase16. Part of the variation in K concentration, however, is also attributable to weathering and transport of detrital material into the basin, linked to humidity  in addition to aridity (reverse weathering). To correct the K values for the effects of dilution by non-clay materials and transport, we normalized K by the zirconium (Zr) values (K/Zr), a proxy for detrital input reflecting the input of clastic material13. Thus, assuming that K/Zr is a faithful recorder of hydroclimatic changes at CHB, we applied a hydro-balance model to estimate the precipitation associated with the changes in K/Zr. During the last African Humid Period (~15–5 kyr) with low K/Zr ratios (<10), an increase of 20–30% annual precipitation (+200 mm yr–1) would have been required for the palaeolake to rise to the outflow level (±45 m above present-day levels)8. Modern conditions of ~900 mm yr–1 and a seasonal shallow lake show K/Zr ratio of ~28 corresponding to the sediment surface  bulk-sediment concentration, determined by X-ray fluorescence (XRF) core scanning13. The youngest part of the record  is characterized by an unprecedented increase in variability with high-frequency alternations13. This period includes the most arid and rapidly oscillating climate of the entire record during episodes 11 (~35–30 kyr) and 12 (~30–10 kyr), but with a strong reduction in sediment accumulation rate, potentially a hiatus, between ~30 and 12 kyr (ref. 9). A reversal towards wetter conditions occurs with the abrupt onset of episode 13 at ~10 kyr, followed ultimately by a shift to modern-day, persistently dry climate conditions  is weak or absent19 , other factors, such as greenhouse gas and ice-sheet forcing, which have been suggested as controls on precipitation over eastern Africa21, could also have had increased influence at CHB (see Supplementary Note The long-term trends in the K/Zr record show an anticorrelation with eccentricity (~125 and 400 kyr cyclicity) and a correlation with precession 19 that reflect the intensity of coastal upwelling in the Arabian Sea and therefore the strength of the summer monsoon. Thus, amplified wet phases in southern Ethiopia may have been enhanced by moisture advection and a stronger summer monsoon in phase with orbital forcing22 , show a much weaker  similarity to the K/Zr moisture index from CHB with possible exceptions during the eccentricity minima between ~430–360 kyr and ~120–0 kyr  Site 72224 from the eastern Mediterranean Sea, dominated by the Nile River outflow, shows a strong similarity to wet–dry shifts recorded at CHB25, arising from the close geographical proximity of the Blue Nile and CHB catchments  that may have created favourable conditions for hominins and a series of shorter episodes (~103 to 104 yr) . While some of this variation may have been reduced by subsequent dispersal during more favourable periods, much persists beyond 275 kyr, where it forms the foundation for the morphological diversity seen in early H. sapiens populations27. Within Ethiopia, the distinct morphs of the Omo I and Omo II fossils provide a snapshot of this diversity28.Favourable habitats for hominins in eastern Africa can be deduced for episodes 1, 2 and 6, marked by relatively long-lasting stable and humid conditions at CHB (Extended Data Table 29)), reflecting a technological trajectory similar to that seen at Olorgesailie3 (Kenya), where a total replacement of Acheulean by MSA technologies had been completed at least by ~320 kyr (refs. 30). While Gademotta shows no Acheulean elements29, Ethiopian localities such as Herto and Mieso show a late persistence of the Acheulean32. Taken together, the Kenyan and Ethiopian records suggest that prolonged periods of variability such as those evident in the CHB record may have driven the gradual replacement of Acheulean by MSA technologies and the spread of H. sapiens. The earliest H. sapiens fossils in eastern Africa (Omo I: >233 ± 22 kyr (ref. 33); Herto BOU-VP-16/1: 156 ± 7 kyr) (refs. 34) also appear during this period; their geographically distinct mosaics of ancestral and derived features are consistent with population isolation caused by habitat fragmentation35.During episodes 7–9 (~275–60 kyr), we infer that a pattern of cyclicity transformed habitats in eastern Africa. This interval shows significantly increased variability, both in frequency and in magnitude of climate swings. This pronounced variability is superimposed on an aridification trend from ~210 kyr that accelerates after ~120 kyr. The onset of this period of high variability coincides with dates for the earliest Middle Stone Age (MSA) occurrence in Ethiopia at Gademotta 36, potentially resulting in allopatric differentiation, expansions could have enabled renewed contact and the spread of beneficial variants10. Such mechanisms have the potential to maintain vital genetic heterogeneity35, promote cultural innovation and diversity38 and enhance rates of cumulative cultural evolution39. Environmental shifts at precessional timescales are slow enough to be mitigated by geographic range shifts; the short-term climate flickers demonstrated at CHB, however, were too rapid (<103 yr) to be entirely accommodated by relocation, particularly in cases where areas of viable habitat were discontinuous. Local extinctions were therefore probably among populations unable to adapt in situ. Populations of slowly reproducing species such as H. sapiens are unlikely to be able to respond to such rapid changes by genetic adaptation alone. Instead, they may have responded plasticly, by utilizing their cognitive abilities to support social learning, with adaptation being primarily cultural40. Although climatic changes and their populational effects are unlikely to be the sole drivers of cultural adaptation, several critical cognitive and societal developments mark this interval as a key phase of technological and social innovation42 that would have equipped H. sapiens with unprecedented adaptability. Evidence of more varied tool kits, long-distance transport and symbolism42 appear during periods of rapid environmental perturbation, demonstrating more developed cultural capabilities among MSA hominins3. Such innovations emerge in situ but subsequently equip populations to disperse into novel environments44. Both technological and social innovations could have buffered early H. sapiens from the impacts of severe environmental changes42.The cyclic climatic variability of episodes 7–9 is likely to have paced the expansion and contraction of habitats utilized by MSA populationsH. sapiens were able to disperse beyond Africa before 60 kyr (refs. 45), although it is not currently possible to identify their distinct geographical origins. Several pronounced wet phases at CHB during episodes 7–9 align with humid pulses in northeastern Africa25 and the Mediterranean26, perhaps opening favourable migration routes out of Africa on a roughly north–south axis along the East African Rift System and into the Levant45. One possibility is that early dispersals involved populations dispersing in line with expansions or shifts of suitable habitat15. As cultural innovations accumulated during episodes 7–9, however, they provided H. sapiens populations with the means to expand beyond their native habitat44, with this expansion ultimately leading to the global dispersal of modern humans11.Some populations of H. sapiens dispersal but also witnesses the further accumulation of innovations within eastern Africa. The transition from the MSA to the Later Stone Age is protracted46 but is signalled by increases in smaller tools such as backed microliths and by bipolar (anvil-assisted) flaking48. Symbolic innovations such as shell beads (at Porc-Epic49) and engraved ostrich eggshell (at Goda Buticha50) occur within Ethiopia during episode 10. Thus, although many of the innovations facilitating widespread dispersal were in place before episodes 10–12, the extreme environmental fluctuations observed during this interval continued to act as a motor for indigenous cultural change.Episode 10 (~60 kyr) begins with a brief but pronounced return to humid conditions, followed by a crucial shift to unprecedented high-frequency oscillations and an increase in aridity. This critical episode encompasses the beginning of the major In summary, the results from the CHB core record suggest that shifting of environmental conditions during the past ~620 kyr could have played a major role in human biological and cultural evolution. This shaped adaptations and provided environmental opportunities facilitating modern human dispersal out of Africa.52. CHB is a deep tectonic, endorheic basin that episodically held a palaeolake hydrologically open during pronounced wet phases, with an outflow to the south at +45 m relative to the current playa surface8. The two coring sites are ~20 m apart, being situated in proximity (~3 km distance) to the western shore of the playa with shallow but extensive alluvial fans (up to 20 km by 10 km), draining the Hammar Range  and 266.38 metres below surface (core HSPDP-CHB-2B)nge Fig. 53. The p52, where archive halves are also permanently curated. Low-resolution (5 cm) multi-sensor core logging (MSCL[-S])54, including magnetic susceptibility, gamma-ray density and p-wave velocity, non-contact electrical resistivity and natural gamma radiation, provided first data for initial core correlation and enabled the parallel processing and description of core sections upon opening. High-resolution line-scan images54 were taken with a Geotek MSCL-CIS digital line-scan core imager for both cores HSPDP-CHB-2A and HSPDP-CHB-2B directly after length-wise splitting and cleaning of the core sections. Initial Core Description using the PSICAT software with a HSPDP description key provided a visual lithological description, including smear slides analyses at boundaries of changing lithologies . On all split core halves, MSCL (MSCL-XYZ)54 in 5 mm resolution was applied, comprising ~55,000 data points for magnetic susceptibility and colour reflectance spectrophotometry 15 , resulting in ~14,000 discrete sediment samples.55.Besides the two contrasting sedimentary facies 1 and 2 , respectively. Before measurements, the samples were treated with sodium pyrophosphate (Na4P2O7) to avoid aggregation. Mineralogical results suggested that the removal of in situ precipitates such as gypsum that can potentially influence grain-size results was not required due to rare occurrences in the mineral suite of CHB samples. Grain-size parameters are based on Folk and Ward56 and were calculated by GRADISTAT software version 857. Granulometric information can be used to provide insights into erosional and transport mechanisms in the CHB catchment, sedimentation dynamics of detrital material and provenance of detritus  are transported primarily by the extensive alluvial fans aggrading from the western rift shoulder into the CHB basin60. Those alluvial fans become increasingly active during generally drier climate conditions in a landscape with reduced vegetation60. Elevated proportions of the finer fractions through the record indicate a relatively high water level of the palaeolake and are typically deposited during humid conditions . In several intervals, clay-enriched beds alternate with sand layers. We interpret intervals with these frequently interchanging layers as reactivation products of the alluvial fans. These layers suggest extreme rainfall with reduced vegetation cover in the catchment during intermittent dry periods. Silt-sized particles are much more abundant throughout the record and dominate beside sand the uppermost 43 metres composite depth (~0–130 kyr)13. High amounts of sand and silt with the absence of clay and fine silt can be indicative of long-lasting dry conditions.Grain sizes were measured for the composite core using a 32 cm interval (743 discrete samples) at the laboratory of the Geographic Institute, University of Cologne. The determination of grain size was performed in 116 channels from 0.04 to 2,000 μm using a laser diffraction particle size analyser (LS 13320 Beckmann CoulterTM). The calculation of grain-size raw data was performed using the Fraunhofer optical model. Before analysis, organic and carbonate content was removed using 15% H58. Sediment colour may be the result of the primary mineralogical constituents and their diagenetic changes reflecting oxic versus anoxic conditions at sediment deposition62. The ratio of haematite versus Ti-magnetite, for example, would be a typical example of minerals represented in the CHB catchment55 responding to oxidation of the detrital Ti-magnetite. Dissolved iron (Fe) and iron-hydroxides may originate from the volcanic bedrocks in the higher eastern boundary of the CHB basin, the Teltele Plateau and from the northeastern part of the catchment, where Cenozoic volcanic rocks are exposed to weathering  and reddish-brown colours during low lake levels (associated with arid episodes)16  shows similar loadings for all colour bands and is interpreted as the total reflectance  and hence not used for further analyses. Instead we use the PC2  with positive loads within the short wavelengths (blue reflected light) as an indicator of wetter conditions in the basin  throughout the core. Sample selection covers areas of high and low peaks as well as in higher resolution (32 cm) transitions between high and low XRF counts (counts per second). The comparison between quantitative XRF data measured on discrete samples and the Itrax core-scanning data facilitates the assessment and potential correction of possible matrix effects. To assess possible variations in the elemental concentration through time, the effect of varying grain sizes, surface effects and water saturation have to be determined by comparing quantitative with the semi-quantitative results. All discrete samples were dried and ground to powder fraction, pressed with equal pressure (2 × 25 kg) into sample holders. All quantitative measurements were performed at the Institute of Geochemistry at MARUM Bremen using a PANalytical Epsilon 3XL energy-dispersive XRF equipped with a rhodium tube, several filters and an SSD5 detector. A calibration based on certified standard materials  was used to quantify elemental counts. Three reference samples were used, indicating that all shown results are well within the limit of detection. The quantitative XRF concentrations in mg kg–1 correlate strongly with the semi-quantitative line scans in counts per second, with Pearson correlation coefficients varying among 0.91 (Fe), 0.80 (Ti), 0.80 (K), 0.94 (Zr) and 0.91 (Ca) for elements within the limits of detection. Matrix effect correction63 and numerical calibration65 for strongly offset scanning results is not applicable given the good agreement between quantitative and semi-quantitative datasets  and coherence scattering. In 2018, three additional standards were developed for better calibration of high-carbonate sediments by dilution of SRM 2711a with reagent grade CaCO3. Pressed powder samples of the SRMs were measured at a resolution of 0.2 mm along their axes, resulting in 25 readings for each of the chemical elements as well as for coherence scattering.XRF core scanning, at 5 mm resolution, was performed at the Large Lake Observatory of the University of Minnesota to determine the elemental sediment composition. An Itrax core scanner with a chromium (Cr) tube as radiation source, a tube voltage of 30 kV, current of 30 mA and scanning time of 10 s was used. Data were normalized to compensate for aging of the Cr tubeThe CHB cores were measured between 16 April 2016 and 12 October 2018, including 21 SRM runs. A weekly correction factor was determined for each element by dividing long-term average values of SRM measurements by the week’s measurements. The values for coherence scattering have been corrected accordingly. The element counts were divided by the normalized coherence scattering and multiplied by the correction factor for the specific week. A small number (24) of sections were re-run in July–August 2019 because they displayed system offsets in light elements that were not fully corrected by the initial normalization process. Quality flags between 0 and 2 have been continuously attributed sub-centimetre wise to the composite core material and have then been applied to each measured data point (= 0.5 cm resolution) for both MSCL and XRF datasets. The quality flags also consider section breaks, with possibly disturbed section ends, cracks, large concretions, coring artefacts or larger voids.55. Authigenic processes such as illitization and zeolitic alteration with increasing alkalinity and salinity have been described for CHB to increasingly alter weathering silicates such as smectites into authigenic phases, at the expense of smectite abundances67. Ca may reflect both endogenic calcites precipitating in the water column of palaeolake Chew Bahir and evaporation in the CHB basin, which is corrected for the influence of weathering in the catchment, with Ti or Zr as a clastic component69. Comparing this proxy with the total inorganic carbon and total organic carbon content of the sediment helped to correct this ratio for the presence of calcium carbonate18. Ti and Fe are typically found in Ti-magnetite and the volcanic bedrock in the CHB catchment  and the K/Zr ratio Fig. 7,16,18,5atchment 16,53,55.Not-a-Number (NaN); (3) each individual data point was flagged according to its quality ), and all data points with flags 1 and 0 were removed from the dataset; (4) outliers were removed by using the filloutliers function of MATLAB, using the generalized extreme studentized deviate test for outliers; and (5) offsets due to scanning artefacts in the data series were detected using the MATLAB-based findchangepts function contained in the MATLAB Signal Processing Toolbox and removed by subtracting the median from the data. Before the following change-point analysis to define environmental episodes and wavelet power spectral analysis, the data were interpolated to an evenly spaced time axis with 0.1 kyr resolution.We used MATLAB R2021a, including the Signal Processing Toolbox and the Statistics and Machine Learning Toolbox, to perform all data processing, analysis and display. All datasets (scanning and logging data) were pretreated in the following way: (1) the data files were cleaned for obvious errors; (2) data voids were replaced by the MATLAB representation for 70, wavelets18 or recurrence plots25. We again used the MATLAB-based findchangepts function, detecting change points71 by minimizing a cost function over all possible numbers and locations of change points (Extended Data Fig. findchangepts for the arithmetic mean (Extended Data Fig. We used a change-point analysis as one of many possible methods for structuring a climate time series such as windowed descriptive statisticscwt. We chose Morse as the mother wavelet, which is very well suited to reproduce the cyclical characteristics of environmental variability in the CHB record25, with a symmetry parameter of 3 and a time-bandwidth product of 15. The wavelet power spectrum shows several significant periodicities that occur in certain periods but are absent in others (Extended Data Fig. y axis reversed between ~435 and 425 kyr, flanked by two episodes with high values at 440 and 415 kyr. A similar episode with a strong ~20–30 kyr cycle occurs between 280 and 220 kyr and an ~20 kyr cycle between 200 and 100 kyr, with a number of shorter, ~10 kyr cycles at ~175 kyr and ~125 kyr, to a lesser extent also at around ~250 kyr, and 5 kyr cycles after ~80 kyr.We calculate a continuous wavelet transformation from the K/Zr record using the MATLAB function Any methods, additional references, Nature Research reporting summaries, source data, extended data, supplementary information, acknowledgements, peer review information; details of author contributions and competing interests; and statements of data and code availability are available at 10.1038/s41561-022-01032-y.Supplementary InformationSupplementary Notes 1–4, Figs. 1–3 and references.


Idiopathic multicentric Castleman disease (iMCD) is a rare lymphoproliferative disorder characterized by a hyperinflammatory state driven primarily by hypercytokinemia, particularly interleukin-6 (IL-6) –3. iMCD Anonymized longitudinal patient data were sourced from Truven MarketScan® Research Databases (IBM), covering 235 million US citizens  from January 2006 to December 2020 , 8. A paTo better understand important features in the longitudinal histories of these patients, we performed a mutual information (MI) analysis of the iMCD population relative to controls. This allowed us to quantify binary features that are statistically most relevant for discriminating between iMCD and non-iMCD patients. The top 15 diagnosis codes by mean MI value across all 6-month periods are provided in Table To analyze disease burden over time, we calculated cumulative proportions of individual morbidities across the group over a 4-year period (±2 years from IDD). To control for confounding, we matched all iMCD patients to non-iMCD controls at a frequency of 1:50 on age group , sex, insurance type, length of claims history in database, and region .T-Test with a significance level of 0.05. A chi-square test without Yates correction was used to identify significance between features described by binary variables.The number of ER visits and inpatient hospitalization days per patient, defined by specific place of service codes, were calculated for each patient in 12 months prior to (1 year before) and 12 months following (1 year after) IDD. When available, ER visits and hospitalizations were also calculated for 13–24 months prior to or following (±2 years) IDD. Multiple ER claims on a single day were counted as a single visit. All significance tests for continuous variables were calculated using Welch’s Unequal Variance Of 30.7 million eligible individuals in the Truven MarketScan® database, 487 patients had a Castleman disease (CD) diagnosis—of which 271 were identified as iMCD based on our algorithm [We performed an unbiased MI analysis to identify the most common morbidities between iMCD and a non-iMCD control population Table . The topOur analysis of iMCD burden over time as a function of ER visits and hospitalization days revealed increased healthcare utilization in the year immediately before and after IDD compared to 2 years before and 2 years after diagnosis Table . A highep < 0.001)  . Among all myeloid malignancies, MDS and MPN accounted for the highest proportion of cases, whereas carcinoma of unknown primary accounted for the most cases of solid malignancies in iMCD patients 01) Fig. . Overallnts Fig. . We addiTo the best of our knowledge, this is the first population level study to comprehensively characterize the pattern and evolution of morbidities in iMCD patients leading up to and following iMCD diagnosis. The key findings of this study include a high proportion of iMCD patients experiencing renal and pulmonary dysfunction, thrombotic events, myeloid malignancies particularly MDS and MPN, and solid tumors particularly carcinoma of unknown primary. We observed an increase in morbidities leading up to the iMCD diagnosis and continued rise (either persistence or emergence of new morbidities) post diagnosis even in the short follow-up period (2 years). This correlated with increased healthcare utilization, potentially reflecting difficulties in establishing the diagnosis and contributing to increasing severity at the time of treatment initiation.Earlier studies have reported an increased prevalence of certain morbidities including a three-fold increased prevalence of malignancy 19%) compared to age-matched controls (6%) in iMCD patients , 5, 8, 9% compareA major strength of this study was reliance on a validated claims-based methodology to identify iMCD cases from a large population cohort and comparison with matched non-iMCD controls, overcoming the limitations of small sample sizes and lack of appropriate control groups seen in previous studies. Given the rarity of this condition, introduction of evidence-based diagnostic criteria and specific disease coding in 2017, and slow recruitment of patients in disease-specific registries, administrative claims databases remain valuable tools for studying natural history and real-world treatment outcomes of rare diseases.Our study has several limitations inherent to health claims datasets, therefore, the findings should be interpreted with appropriate caution . As claiwww.CDCN.org/ACCELERATE) [This study enhances our understanding of the natural history of iMCD particularly related to the development of morbidities with implications for early diagnosis and timely treatment. Further research is ongoing using orthogonal approaches such as the ACCELERATE Registry (ELERATE)  to asses


PTT and LVET were also found to decrease through HDT bed rest (p < 0.01). Furthermore, PTT and LVET magnitude of response to bed rest was found to be different between campaigns (p < 0.001) possibly due to seasonal effects on of the cardiovascular system. Correlations between FDA and cardiac timing intervals PTT and LVET using SCG suggests decreases in mechanical strength of the heart and increased arterial stiffness due to fluid shifts associated with the prolonged bed rest.During head-down tilt bed rest (HDT) the cardiovascular system is subject to headward fluid shifts. The fluid shift phenomenon is analogous to weightlessness experienced during spaceflight microgravity. The purpose of this study was to investigate the effect of prolonged 60-day bed rest on the mechanical performance of the heart using the morphology of seismocardiography (SCG). Three-lead electrocardiogram (ECG), SCG and blood pressure recordings were collected simultaneously from 20 males in a 60-day HDT study . The study was divided into two campaigns of ten participants. The first commenced in January, and the second in September. Signals were recorded in the supine position during the baseline data collection (BDC) before bed rest, during 6° HDT bed rest and during recovery (R), post-bed rest. Using SCG and blood pressure at the finger, the following were determined: Pulse Transit Time (PTT); and left-ventricular ejection time (LVET). SCG morphology was analyzed using functional data analysis (FDA). The coefficients of the model were estimated over 20 cycles of SCG recordings of BDC12 and HDT52. SCG fiducial morphology AO  and AC  amplitudes showed significant decrease between BDC12 and HDT52 ( The once unequal gradient pressures in blood vasculature now equalize, affecting blood pressure regulation and cardiovascular control9 Seen in both short and long-term spaceflight, upward fluid shifts have been associated with increased orthostatic intolerance post flight13.The human cardiovascular system has evolved to operate in the presence of gravity16. There are interventions being investigated to act as countermeasures to stem the physiological deconditioning of spaceflight  application, exercise activities, short-arm centrifugation, plasma volume replenishment, and nutrient supplementation)21, However, little is known about the effects of extended weightlessness on arterial stiffness and systemic vascular resistance. Hughson et al. showed an increase in arterial stiffness of astronauts after six months aboard the International Space Station similar to that of 10–20 years of aging22. The arterial stiffness increase was based on observations of decreased pulse transit time (PTT) and lowered biomarkers, such as insulin22. Pulse wave transit time has also been reported to be decreased even after 5 days of spaceflight23.Continuing effects of physical unloading in microgravity can drive cardiovascular remodeling and arterial changes leading to mechanical attenuation of heart function and advanced arterial stiffness26 Head down tilt bed rest has been shown to mimic the effects of weightlessness on the body including upward fluid shifts27. Several studies indicate that vascular remodeling after long-duration bed rest produces sustained decrease left ventricular mass during bed rest while causing drastic deconditioning of left ventricular volumes34, although, a recent study found that ventricular mass loss did not occur35. However, in spaceflight, there is a chronic decrease in left ventricular mass of values close to 9–12% loss while in similar observations during HDT studies show 8–16% mass losses36, Alternatively, decreases in left ventricular volumes have been attributed to blood plasma loss during bedrest also seen in spaceflight35. In tandem to ventricular remodeling, responses of blood pressure have been shown to lower during head-down tilt bed rest (HDT) analogous to spaceflight39.A major limiting factor in the interpretation of spaceflight data is the relatively low sample size of individuals who have experienced spaceflight. Therefore, conditions such as 6° head-down tilt bed rest are routinely used as space analogs to simulate the effects of microgravity40. Techniques used to measure cardio-mechanical vibrations have been used to observe deconditioning of the cardiovascular system in spaceflight and early hemorrhage detection44.The current study focused on the mechanical performance of the heart during 60-day HDT. With each heartbeat there are mechanical events that give a windowed look into cardiac performance. Cardio-mechanical techniques such as, Seismocardiography (SCG), evaluated via a local accelerometer placement on the chest, can measure cardiac motion, giving information about heart valve opening and closure events45. Another study by Di Rienzo et al., used SCG techniques for monitoring vital signs during sleep of astronauts on the ISS46. In that study, the group used the smart garment with a three-axis SCG on the sternum and a three-axis gyroscope to gather cardiovascular vibrations on the chest and evaluate cardiovascular data during sleep. Initial analysis was done on one astronaut crew member using timing intervals of isovolumic contraction time (ICT), isovolumic relaxation time (IRT), LVET, and pre-ejection period (PEP) over seven sleep intervals46.In development of a smart garment, Di Rienzo et al. utilized left ventricular ejection time (LVET) and QS2  as measurements of heart contractility43. Of the features derived by SCG, timing intervals of LVET and PEP were shown to be highly correlated to changes during graded LBNP. This correlation suggested that changes of SCG-derived features  in emergency scenarios can be used as warning signs of early hemorrhage43.Detection of the effects of early-stage hemorrhage have also been investigated through using SCG. Tavakolian et al., investigated simulated hemorrhage through graded LBNP to quantify correlations between stroke volume via echocardiography and SCG features47 and cardiovascular timing intervals49. It was hypothesized that with increased headward fluid shifts during HDT there would be a decrease in SCG amplitude strength due to mechanical deconditioning of the heart. As a secondary hypothesis, it was predicted that PTT would decrease due to increased arterial stiffness associated with HDT.This investigation utilized the HDT space analog together with cardio-mechanical responses of the heart to further the understanding of cardiovascular compliance and resultant arterial stiffness. The cardiovascular vibration technique of SCG was used to provide insight into the mechanical deconditioning of the heart through relationships between blood pressure37. The experiments were conducted as an ESA funded study at the Institut de Médecine et de Physiologie Spatiales (MEDES), a Centre National d’Études Spatiales (CNES) facility located in Toulouse, France. This prolonged bed rest study was broken into three phases. Phase one consisted of 14 days of baseline data collection (BDC) prior to head down tilt, phase two consisted of 6-degree head-down tilt (HDT) bed rest for 60 days and phase three was a recovery period (R) 14 days after head-down tilt. Ethical approval was obtained from the Comité de Protection des Personnes / CPP SudOuest Outre-Mer I and the Agence Française de Sécurité Sanitaire des Produits de Santé for each facet of the experimental protocols. Additionally, approval of this study was obtained by the Office of Research Ethics at Simon Fraser University. The participants signed a written informed consent prior to taking part in the study.The head-down tilt bed rest study consisted of two campaigns of 10 volunteers each lasting 60 days. Campaign 1  was started in January 2017 while Campaign 2  was started in September 2017. The clinical trial was registered at ClinicalTrials.gov (Identifier: NCT03594799). An all-male cohort (N = 20) participated in this experiment (ages ranging from 20–45). The experimental group consisted of nutrient countermeasure group randomly selected (N = 10) and control group (N = 10). This study data collection followed in-line with our previous study of cardio-postural effects of prolonged bed rest37. Two of the STS collections were taken during baseline before bed rest (BDC) and post bed rest recovery (R). The data collection for STS was taken at the same time on BDC12 (12 days before) and BDC2 (2 days before) for baseline before bed rest. Data collection of STS after bed rest was taken at R8 (8 days after bed rest). STS data collection consisted of 5 min of collection in supine and 6 min of data collection during standing. In this investigation, only the supine portion of STS testing was investigated for cardiovascular function . During HDT, the cardiovascular function was assessed at 6 degrees head-down for 10 min via ECG, blood pressure, and SCG at the same time in the morning on days of HDT 1, 29 and 52 (days during head-down tilt). Plasma volume was measured using CO rebreathe and were made as part of the standard bed rest protocol used by ESA24.Data collection days and times were selected to avoid conflict with the ESA orthostatic tolerance testing. In the previous study protocols, supine to stand (STS) were used to assess the relationship of cardiovascular control and postureContinuous blood pressure was collected via non-invasive Portapres . SCG was collected by a unidirectional accelerometer in the dorso-ventral direction positioned on the xiphoid process of each subject. The SCG measured the vibrations of the heart as a resultant beat against the chest wall during each cardiac cycle. Electrocardiogram (ECG) was collected using three lead ECG positioned in a Lead II configuration . Experimental setup shown in HDT schematic  and AC  were annotated on SCGm48 Fig. . Additio52. Similar techniques have been used in analysis and interpolation of SCG fiducial points55 In FDA, each SCG cycle was modeled as the linear combination of 23 spline base functions of order 4. The coefficients of the model were estimated and compared over 20 cycles of SCG recordings between BDC12 and HDT52 for the 20 subjects.Beyond individual fiducial points, the entire morphology of SCG was analyzed by functional data analysis (FDA) using MATLAB R2019a37. If no significance was found between control and countermeasure group, then the participants were merged for further analysis. Normality test was conducted using Shapiro-Wilk at α = 0.05.Nutrient countermeasure was randomized amongst participants. Statistical analysis of Cocktail countermeasure followed the same technique as outlined in previously reportedFor normally distributed data, two-way ANOVA with replication was completed followed by a Bonferroni correction comparing cardiovascular changes due to bed rest between BDC12 compared to HDT01, HDT29, HDT52 and R8 in addition to campaign 1 and campaign 2 for seasonal differences. For non-normally distributed data a nonparametric test was conducted using the Friedman test. A probability of α < 0.05 was considered significant. Additionally, the Wilcoxon Signed Rank test was performed to evaluate the differences between FDA coefficients for BDC12 and HDT52, to determine SCG morphology changes.37, the cocktail countermeasure had no effect on the cardiovascular values, and our analyses indicated that this was also the case for the timing intervals in this study .As previously reported by Xu et al.The heart was analyzed via the vibration peaks caused by the heart hitting the chest wall during each beat. These vibrations morphologies AO and AC detected at the xiphoid process by the SCG showed a lowering trend through bed rest. Through FDA, the coefficients of corresponding spline basis functions describe the SCG waveform in 23 knots. These knots act as windows of the signal dividing it into sections defined by the specific splines shown to represent SCG morphology. The coefficient sets showed wider distributions at the end of bed rest compared to the baseline data collection sets. Spline basis coefficient sets 4, 5 and 6 describe the AO peak complex, while Spline coefficient sets 14, 15, and 16 describe the AC peak complex . PTT from the AO peak of SCG to the foot of the blood pressure at the finger, revealed a drastic decrease immediately into bed rest for both campaigns . The PTT interval did not recover by R8. Additionally, there were significant differences between the campaigns (p < 0.01). PTT decrease more drastically between pre- to post-bed rest in Campaign 1 compared to Campaign 2 . This trend was seen in both campaigns; however, like PTT, there was a significantly greater change of LVET between campaigns 1 and 2  for both campaigns. Campaign 2 had less of an increase in HR compared to campaign 1, significant differences at BDC12 and R8. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) showed significant changes across bed rest phases (p < 0.04). Additionally, there were large significant differences in these changes between campaigns 1 and 2 in blood pressure values. Through bed rest, campaign 1 had lower systolic (p < 0.001) and diastolic blood pressures compared to campaign 2 . No significant change was seen between campaigns (p = 0.45). Additionally, fitness levels (V̇O2max) of the participants when they entered the study (BDC 8 baseline) were not different between campaign 1 (39 ± 4 ml/min/kg) and 2 (40 ± 4 ml/min/kg). Fitness decreased by similar amounts in both campaigns to of 31 ± 4 ml/min/kg  and 29 ± 2 ml/min/kg .Heart rate (HR) had a gradual increase through the entirety of bed rest and 8 days post HDT on R8  and apex-SCG were used as monitoring techniques of kinetic energy instead of vibrational peaks and cardiovascular timing. These relationships were used to show the promise of a reactive jump exercise toward prevention of orthostatic intolerance. However, placement of the SCG beyond the traditional sternum placement creates a signal susceptible to noise artifacts58.Cardiovascular vibrational assessment techniques have been used in a multitude of previous studies. One such technique parallel to SCG is that of ballistocardiography. Ballistocardiography can record recoil ballistic forces which occur as blood is ejected into the vasculature can be measured through multiaxis sensor placement on the body,36, Ventricular mass losses have also been observed in previous bed rest studies34. These changes in mass produce hinderances in both left ventricular end-systolic volume and end-diastolic volume. However, vascular changes and pressure regulatory responses to fluid shifts cause relatively quick recovery stabilization of the left ventricular end-diastolic volume59, while left ventricular end-systolic volume tends to continue to increase during prolonged weightlessness suggesting a reduction in cardiovascular compliance and functional performance60.Vibrational signals are dependent on mass components of the system, defining the equations of motion. In addition to increased upward fluid retention, systemic loss of cardiovascular mass can contribute to the lowered mechanical peak performance. In spaceflight, there is a chronic decrease in left ventricular mass of values close to 9–12% loss while a similar observation during HDT studies show 8–16% mass lossesAs shown in the decreased averages and distributions of the FDA spline basis coefficient sets, there are displays of underlying structural changes in SCG peak complexes Fig. . Upon en14, Resultant increases in LVET at HDT01 seen in our study are defined by these decreases of blood pressure which could be a response to increased stroke volume  were not significantly different between baselines and recovery stages. Average values of campaign 1 and campaign 2 differed by only 1 ml/min/kg  differed only by 2 ml/min/kg  values showed lower trends. These changes could potentially be attributed to the seasonal differences (that can influence vaso-control of vasculature) in the two campaigns. As campaign 1 was started in January, SBP in this season is expected to be higher due to constriction of vasculature for thermal regulatory responsesnse Fig. . Between65. Norsk et al. points to both cardiovascular shifts and thermal regulatory responses to decreases of systemic vascular resistance in prolonged spaceflight25. Our results from prolonged bed rest confinement suggest that training temperature of the astronaut and the environmental temperature during spaceflight could potentially influence the changes in cardiovascular function and/or cardiovascular responses. In addition, such temperature changes could further influence the impacts associated with upward fluid shifts and vascular remodeling during prolonged bed rest.Due to the influences of thermal regulatory responses, potential effects of seasonal changes should be considered in future bed rest studies. During prolonged spaceflight Stahn et al. investigated that core body temperature increases 1 °C which can have an effect on task performance67, Future studies should, therefore, include both males and females. Plasma volume loss was not directly studied in the scope of this investigation as a correlation to seasonal changes and cardiovascular timing. Future studies should investigate blood volume as a potential metric of cardiovascular and thermal strain. Another limitation of this study is that temperature was not controlled. As our results show, temperature changes could potentially affect several parameters. Future bed rest studies should take into account the effects of seasonal changes on cardiovascular and other responses.In this study, the participants involved were all males. It has, however, been shown that cardiovascular responses are influenced by sexDuring spaceflight, the cardiovascular system alone experiences rapid deconditioning due to vascular changes occurring during upward fluid shifts. Prolonged head-down tilt bed rest has shown to be analogous to the impacts seen in microgravity. This study has shown the loss of mechanical strength of the heart due to prolonged head down tilt bed rest. Our results supporting the hypothesis of continued attenuation of heart vibrations resulting from HDT. The physical-mechanical strength loss seen from the peak inflections of SCG in tandem with blood pressure responses, suggest that prolonged fluid shifts result in the quickening of cardiovascular timing intervals corresponding to vascular changes. The rapid drop in PTT had shown that immediately experiencing fluid shifts cause faster blood distribution transition times to the finger, resulting in the potential for increased arterial stiffness and lowered arterial compliance. Quickening LVET appears to be correlated to the decreases in mechanical strength of the left ventricle, which could arise due to changes in blood volume and ventricular mass loss associated with the HDT.Our results show that seismocardiography can provide higher fidelity information about the mechanical performance of the cardiovascular system during prolonged HDT bed rest. As the heart beats, there are critical time elements that correspond to resultant vibrations. Traditional, techniques that are utilized to gather cardiovascular data overlook this mechanical stimulus and require complex instrumentation. Complex equipment can make monitoring difficult in both operational spaceflight tasks  or during routine medical checkups. Single sensor placement of the SCG can yield crucial cardiac information with less instrumentation and opens monitoring techniques to wearable technologies  for spaceflight applications as well as home care monitoring. Insight gained from this study can be further used to gain understanding of how the vasculature and heart adapts mechanically to sedentary bed rest or simulated prolonged weightlessness.68, Not only can the use of analogs such as HDT build upon our understanding of spaceflight physiology, but they can also aid in terrestrial medical applications.Finally, The results of this study can give insight into the continuing cardiovascular changes due to aging as well as the consequences of bed rest confinement during hospitalization


Adolescents with polycystic ovary syndrome (PCOS) are at increased risk of impaired glucose tolerance (IGT) and type 2 diabetes mellitus. The aim of this study is to evaluate dysglycemia and biochemical differences based on BMI status and assess the prognostic ability of elevated hemoglobin A1c (HbA1c) in predicting an abnormal 2 hour oral glucose tolerance test (OGTT).Retrospective cohort of female patients aged 11-18 years who underwent 75-g OGTT and were evaluated for PCOS at an urban tertiary care hospital between January 2002 to December 2017.p < 0.001) compared to patients without obesity. Free testosterone levels were also higher in patients with obesity (p< 0.03) and were significantly associated with HOMA-IR when controlling for body mass index (BMI). HbA1c did not demonstrate a strong ability to predict abnormal OGTT on receiver operating characteristic (ROC) curve analysis ).In 106 adolescents with PCOS who had OGTT results available, IGT was markedly pronounced in the ≥95th percentile BMI group  compared with <95th percentile BMI group . One patient with obesity met the criteria for type 2 diabetes. Patients with obesity had significantly higher homeostasis model assessment (HOMA-IR) and lower whole body insulin sensitivity index (WBISI) (In a study to assess glucose abnormalities in adolescents with PCOS, IGT was found to be markedly increased in patients with obesity, with abnormal glucose metabolism identified in over one-fifth of the patients. HbA1c alone may be a poor test to assess IGT and we recommend that adolescents diagnosed with PCOS and obesity undergo formal oral glucose tolerance testing. Polycystic ovary syndrome is one of the most common endocrine disorders affecting adolescent females –4 and isMost studies of abnormal glucose tolerance in adolescents with PCOS have a relatively small number of patients and lack a comprehensive evaluation of the associated metabolic abnormalities. In a previous study , a groupObesity appears to influence metabolic as well as clinical characteristics in patients with PCOS , 9. It iIn addition, abnormal glucose metabolism in PCOS is associated with many of the known risk factors for metabolic syndrome , 15, whiOGTT is cumbersome and not performed at all centers. In this study, we assessed serum HbA1c levels, which are simpler to perform, for their utility as an indicator of abnormal glucose tolerance in adolescent patients with PCOS. In addition, we also analyzed the relationship between insulin sensitivity and testosterone levels in adolescents with PCOS. It is important to identify which subgroup of patients in this population would benefit most from dysglycemia screening.This study aimed at evaluating dysglycemia and biochemical differences based on BMI status in adolescent female patients and assessing the prognostic ability of elevated hemoglobin A1c (HbA1c) in predicting an abnormal 2-hour oral glucose tolerance test (OGTT).This retrospective study included female patients with a diagnosis of PCOS aged 11 to 18 years, who were evaluated at the pediatric endocrinology clinics of a tertiary urban academic medical center between January 2002 and December 2017. In order to be included in the study, patients had to have undergone an OGTT and/or HbA1c screening (based on physician preference) as part of routine clinical care. For patients who underwent both OGTT and HbA1c screening, both tests had to be performed within within a three-month time frame , 17. Of PCOS was defined as per the Androgen Excess Society (AES) 2009 criteria which includes presence of hyperandrogenism , ovarian dysfunction (oligo-anovulation and/or polycystic ovaries), and the exclusion of related disorders . The AmeLaboratory data extracted from the medical record included HbA1c in addition to 0, 30, 60, 90, and 120-minute glucose and insulin values obtained during the OGTT. Serum glucose measurements were performed using ADVIA® Chemistry XPT systems, and serum insulin measurements were performed using ADVIA® Centaur Insulin assay, a two-site sandwich immunoassay that uses direct chemiluminescent technology. The HbA1c analysis was performed using Tosoh Automated Glycohemoglobin Analyzer, which uses non-porous ion-exchange, high-performance liquid chromatography (HPLC). The additional laboratory data extracted included total and free testosterone, obtained at a certified laboratory (Quest or Labcorp). Free testosterone was obtained by equilibrium dialysis, and total testosterone was obtained using chromatography-mass spectrometry.Data were described as N (%) for categorical variables and median [IQR] for continuous variables after assessing for normality with the help of the Shapiro-Wilk tests. Dysglycemia and biochemical differences were compared between BMI groups by Chi-squared/Fisher’s Exact tests or Wilcoxon rank-sum tests. The HOMA-IR and WBISI ratios were calculated. A receiver operating characteristic (ROC) curve was generated to assess the prognostic ability of HbA1c with impaired two -hour glucose tolerance. The relationships between testosterone with HOMA-IR and WBISI were assessed using linear regressions. The study was approved by the Institutional Review Board at Weill Cornell Medical College. All analyses were two-sided, with statistical significance evaluated at the 0.05 alpha level. The analyses were performed in R version 3.5.3 .The demographic and biochemical characteristics of our study subjects are detailed in Table N=72) in comparison with those without obesity   ) (Table The median BMI was 30.7 (interquartile range 27.4–35.7) kg/m2, and the median BMI z-score was 1.96 (interquartile range 1.47–2.25). Significant differences in several biochemical characteristics were observed between patients with obesity (Patients with PCOS and obesity had significantly higher insulin resistance on OGTT as defined by HOMA-IR 4.02 vs 1.79) and lower insulin sensitivity as defined by WBISI (2.00 vs 5.13) compared to the group without obesity (p < 0.001 for both HOMA-IR and WBISI)  had both OGTT and HbA1c results available within a three-month period. The median HbA1c for the population was 5.40% (interquartile range 5.20–5.80)  and approached statistical significance with HOMA-IR when controlling for BMI . Free testosterone was significantly associated with HOMA-IR alone  and also when controlling for BMI . Neither total testosterone nor free testosterone were significantly associated with WBISI, either alone or when controlling for BMI  diagnosed with PCOS. These recommendations were mostly based on adult study data and did not look specifically at dysglycemia in adolescents with PCOS.There has been a debate on the optimal screening test for diagnosing glucose abnormalities in adolescents with PCOS, and the recommendations have been varied. A study  showed tA few studies have compared HbA1c to OGTT for diagnosing dysglycemia in adolescents with PCOS. One study  recommen>95th percentile should undergo OGTT. The utility in patients with BMI < 95th percentile and cost effectiveness still needs to be determined.In our study, we analyzed the use of HbA1c as a predictor for IGT. We described the poor predictive ability of HbA1c based on ROC analysis. A normal HbA1c value may be falsely reassuring, and undergoing a formal OGTT may identify dysglycemia in this patient population. Based on the differences we found in patients with and without obesity, we recommend that all patients with a BMI We also found that higher free testosterone levels correlate with higher insulin resistance (as defined by HOMA-IR). Hence, an elevated free testosterone level may be an indicator of the presence of insulin resistance and may be of additional utility in the assessment of this group of adolescents.Our study has various limitations. Its retrospective nature did not allow us to assess all patients systematically, and the clinical decision to perform glucose screening was provider dependent. In addition, due to the retrospective design of our study, a comparative non PCOS control group has not been included for comparison. The strengths of our study include assessment of variables aside from glucose tolerance, and a diverse heterogeneous population from a tertiary care urban healthcare center.Low hepatic sex hormone- binding globulin (SHBG) production may be a key step in the pathogenesis of PCOS. There is emerging evidence that serum SHBG levels may be a useful diagnostic biomarker and therapeutic target for managing women with diagnosis of PCOS . It may >95th percentile. We found that HbA1c is a poor predictor of IGT when compared to a standard 75 gram OGTT. In addition, patients with higher free testosterone levels show higher association with insulin resistance irrespective of BMI – an association that requires further study. We believe that all adolescent patients with PCOS and BMI > 95th percentile should undergo a formal OGTT in order to further help identify individuals who may be at risk of developing type 2 diabetes and may potentially benefit from early initiation of medical therapies and diet and lifestyle changes.We have described the presence of glucose abnormalities in adolescent patients diagnosed with PCOS, with increasing rates of IGT and insulin resistance in those with a BMI


PLOS Biology, Han and colleagues identify a new role for Cerebellin-1 in axon growth and guidance.The cerebellin family of proteins influences synapse formation and function. In this issue of  In development, neurons are faced with an immense challenge. As neurons grow and develop their intricate, complex shapes, they must also grow in the appropriate directions. In particular, their thin, elongated axon can travel large distances to connect with postsynaptic partners. In the past decades, the scientific community has identified an expansive catalogue of attractive and repulsive axon guidance cues that serve as road signs for the growing axon. The nature of the cues varies greatly at the molecular level—some act as soluble, chemotactic cues, while others act as adhesive, haptotactic cues. Often amplified by differentially expressed extracellular receptors and coreceptors, this vast collection of guidance cues enables different axons to navigate to precise and distinct positions in a neuron subtype-specific way.Interestingly, in recent years, a number of proteins and pathways involved in axon guidance have also been shown to be involved in the developmentally distinct process of synaptogenesis . This retrans-synaptically, binding both presynaptic neurexins and postsynaptic GluD2 [Cerebellin-1 (Cbln1) was first described as a glycoprotein secreted in the cerebellum where it is required for proper synaptic function between parallel fibers and Purkinje cells . Notablyic GluD2 . Althougic GluD2 ,5. For eic GluD2 . HoweverPLOS Biology, Han and colleagues report a new role for Cbln1 in axon growth and guidance [In this issue of guidance  Fig 1)..PLOS BioCbln1 showed impeded axonal growth. Similar decreases in axon length and number were observed in Cbln1 cKO DCN explants. Critically, the addition of recombinant Cbln1 protein to culture media rescued these stunted axonal phenotypes.As this expression pattern suggested a potential role for Cbln1 in axon guidance, the authors used a conditional knockout (cKO) mouse to delete Cbln1 specifically in spinal cord DCNs. In vivo, DCNs lacking Consistent with previous studies in cerebellar granule cells , the autCbln1 cKO mouse, axon guidance deficits were once again observed. In particular, the ventral commissure—the bundle of axons crossing the midline—was thinner and changed in shape.In parallel, the authors also focused on the role of Cbln1 in the floor plate—could secreted Cbln1 from this structure influence DCN growth? Upon creating a floor plate–specific Having identified a new role of Cbln1 in spinal cord axon guidance, Han and colleagues also examined axonal growth and guidance in other brain structures. Returning to the roots of Cbln1 research, the authors explored Cbln1 expression patterns in the cerebellum. Similar to the spinal cord, Cbln1 was expressed at early time points and was required for proper axon outgrowth from cerebellar granule cells. Finally, the authors focused on the optic chiasm. Interestingly, retinal ganglion cells do not express Cbln1, but nearby cells in the ventral diencephalon do. Akin to the spinal floor plate, the secretion of Cbln1 from the diencephalon influenced the guidance of retinal ganglion projections.This research highlights an exciting fundamental role for Cbln1 in axon growth and guidance that is conserved in multiple regions of the brain. With this precedent, future work is warranted to determine if Cbln1 plays a role in additional midline crossing events—such as the formation of the corpus callosum in the cortex. Likewise, synergy between different pathways fine-tunes axon pathfinding. Whether coordination exists between Cbln1 and other guidance cues—whether they be attractive or repulsive—is an open question.Of note, Cbln1 is just 1 protein in the 4-member cerebellin family. Interestingly, Cbln1 and Cbln3 form mixed multimers and are secreted together from cerebellar granule cells , suggestFurthermore, this work also highlights the dual roles of Cbln1-mediated axon growth and guidance—cell autonomous and noncell autonomous—as both DCN-secreted and floor plate–secreted Cbln1 influence DCN pathfinding. However, it will be interesting to test if both secreted forms of Cbln1 play distinct roles in axon growth and guidance, perhaps varying in their splicing or posttranslational modifications? Similarly, whether Cbln1 acts as a soluble chemotactic cue or adhesive haptotactic cue remains to be defined.Finally, Cbln1 is identified as another example in which a secreted protein and its extracellular receptor plays a role in both axon guidance and synaptogenesis. However, the authors ponder if synaptic signaling pathways downstream of Cbln1-Nrxn2 are conserved in axon guidance. Similarly, we also question if Cbln1 signaling may influence other early stages of neuronal morphogenesis, such as dendritic arborization. As the list of molecular cues playing a role at multiple developmental time points increases, the field will undoubtedly start testing how these cues can switch between fundamentally distinct processes, yet maintain temporal coordination.