PML::RARA in a 3-year-old boy. Astolfi et al. firstly identified partial integration of the TTMV genome into RARA intron 2, which resulted in in-frame TTMV::RARA fusion in two APL-like pediatric cases without PML::RARA in November 2021. This fascinating report identified an unexpected exogenous genetic cause of APL and could be of great importance for diagnosing and managing APL. Here we report the third childhood APL-like case caused by TTMV integration and investigate the location and structure of the integrated TTMV sequence. These findings suggest TTMV::RARA is a recurrent cause of APL lacking PML::RARA. Considering the widespread prevalence of TTMV in the population, more TTMV::RARA positive APL-like cases might remain to be identified. Establishing a bioinformatic analysis strategy optimized for the highly variable TTMV genome sequence may facilitate the identification of TTMV::RARA by whole transcript sequencing. An effective PCR protocol to identify TTMV::RARA based on a profound analysis of the conservation of TTMV segments in the fusion transcript is also expected. Also, further investigation is needed to elucidate the oncogenic mechanisms of TTMV integration and the clinical features of TTMV::RARA positive patients.In this manuscript, we report torque teno mini virus (TTMV) as a cause of acute promyelocytic leukemia (APL) lacking  PML::RARA fusion. They identified partial integration of the TTMV genome into the intron 2 of the human RARA gene, which resulted in in-frame TTMV::RARA fusion transcripts in two APL-like pediatric cases without PML::RARA fusion. This is a fascinating report because it identified an unexpected exogenous genetic cause of APL and could be of great importance for diagnosing and managing APL, especially given the widespread recessive carriage and transmission of TTMV in the population.Astolfi et al. , 2 firstTTMV::RARA positive APL-like cases, we retrospectively performed a principal component analysis comparing 74 PML::RARA-positive APL cases, 343 oncogenic fusion gene negative AML cases, and 50 healthy controls in our whole-transcriptome sequencing (WTS) cohort  and 23.6 s , respectively. Morphologic examination of bone marrow (BM) smears disclosed infiltration by 73.6% of hyper-granular promyelocytes. Flow cytometry (FCM) revealed 84.1% of myeloblasts . The presumptive initial diagnosis of this patient was APL. However, both reverse transcription PCR (RT-PCR) and fluorescence in situ hybridization failed to detect the PML::RARA fusion in the BM, and the karyotype was normal. Next-generation sequencing mutation analysis of 86 genes that are frequently mutated in hematological malignancies revealed FLT3-ITD mutation.The index case was a 3-year-old boy initially admitted to a local hospital because of persistent fever and headache. Blood tests showed white blood cell count of 36.76 × 109/L after four-day treatment, and induction chemotherapy  was started concomitantly. ATRA was discontinued seven days after ATRA initiation due to the absence of PML::RARA. Follow-up monitoring 21 days after induction chemotherapy showed 13% of myeloblasts and promyelocytes in BM. Then he received consolidation therapy  and achieved complete remission (CR).Given the clinical suspicion of APL, the patient was immediately treated with ATRA and hydroxyurea. The white blood cell count increased to 128.52×10However, one month after achieving CR, the patient suffered from recurrent fever and was admitted to our hospital. BM morphology examination showed that 60% of nucleated cells were blast cells with abundant purple granules, irregular nuclei, and cytoplasmatic budding, while negative for Auer rods . The patRARA transcript sequence in WTS data of this case. Alignment of the WTS data in integrative genomics viewer (IGV) revealed abundant RARA fusion transcripts with a 5’ extension from RARA exon 3, which is not homologous to any human sequence  and Sanger sequencing confirmed the insertion of 1164 bp exogenous fragment at chr17: 40332265 in RARA locus. The first case was a 6-year-old girl diagnosed as hypergranular APL based on the characteristic morphologic features. The patient received CR after treatment combining standard AML induction therapy and ATRA, followed by 3 high-dose cytabine-based courses of consolidation therapy. She relapsed 8 months later and achieved CR after receiving combination of ATRA and ATO. Then she underwent HSCT and was alive at 4 years after HSCT. The second case was a 3-year-old AML child reported in the same literature. TTMV::RARA fusion in this patient was identified by a retrospective in silico analysis in a WTS database of 22 pediatric cytogenetically normal AML cases and the laboratory and clinical data were not detailly described (TTMV::RARA fusion in a 39-year-old man diagnosed as AML with APL characteristics but without PML::RARA. He was initially treated with the standard 7+3 regimen and showed induction failure. He then received mitoxantrone, etoposide, and cytarabine with decitabine and venetoclax with a response. TTMV::RARA is a recurrent cause of APL lacking PML::RARA fusion.We here report the third childhood APL-like case caused by the integration of TTMV fragment into the escribed , 2. Receescribed  reportedTTMV::RARA positive APL-like cases might remain to be identified. Establishing a bioinformatic analysis strategy optimized for the highly variable TTMV genome sequence may facilitate the identification of TTMV::RARA by WTS data analysis. An effective PCR protocol to identify TTMV::RARA is also worth expecting, but this should be based on a profound analysis of the conservation of TTMV segments in the fusion transcript. Also, further investigation is needed to elucidate the oncogenic mechanisms of TTMV integration and the clinical features of TTMV::RARA positive patients. The first reported case was successfully treated with ATRA and ATO and subsequent HSCT. However, as ATRA was coupled with chemotherapy and HSCT, it is almost impossible to assess the contribution of ATRA. The outcomes of the other two reported cases were not available. In addition, our patient in the current case report died after giving up treatment and the efficiency of ATRA was unclear since ATRA was used only for 7 days. Therefore, further studies into the optimal therapeutic approaches for patients with TTMV::RARA are urgently needed.Considering the widespread prevalence of TTMV in the population, more The datasets presented in this article are not readily available because of ethical/privacy restrictions. Requests to access the datasets should be directed to the corresponding author.The studies involving human participants were reviewed and approved by The Institutional Review Board and Ethical Committee of the Hebei Yanda Lu Daopei Hospital. Written informed consent to participate in this study was provided by the participants’ legal guardian/next of kin.HL designed the research; XC designed molecular studies and wrote the paper; PC, JF, QC, and XiuM performed bioinformatics analysis; FW, YZ, JC, and MingL supervised clinical and experimental findings; XZ, XiaM, LY, and MingyL performed molecular studies; YL was involved in the management of the patient and provided clinical data. PW performed morphological analysis. All authors reviewed the manuscript and contributed to the final draft.


However, data on chronic complications are still lacking.Here we report the cases of 3 patients with procedure-related premature ventricular complexes (PVCs) following LBBAP.A 67-year-old man with a history of symptomatic persistent atrial fibrillation despite pulmonary vein isolation and optimal antiarrhythmic therapy, complicated with a reduced left ventricular ejection fraction of 40%, and normal coronary arteries, underwent the implantation of a single-chamber pacemaker with LBBAP, followed by atrioventricular node ablation.Left bundle branch pacing was performed using a SelectSecure 3830 lead . Radiofrequency atrioventricular node ablation was then performed, resulting in a complete atrioventricular block. The pacemaker was then set to a VVIR mode with a rest frequency of 75 beats per minute.The patient presented 1 month later at the emergency department for palpitations. Physical examination was normal except for irregular pulse. The patient’s 12-lead electrocardiogram  showed aPacemaker interrogation showed a persistent complete atrioventricular block, confirming the diagnosis of PVCs and absence of repermeabilization of the atrioventricular node. Pacemaker interrogation showed a 20% burden of sensed ventricular complexes.An 80-year-old woman with a history of symptomatic persistent atrial fibrillation and atrial tachycardia despite antiarrhythmic therapy, electrical cardioversion, and 2 ablative procedures underwent the implantation of a single-chamber pacemaker followed by atrioventricular node ablation as a means to control heart rate. Considering the risk of left ventricular dyssynchrony consecutive to the pacemaker implantation with permanent right ventricular pacing, it was decided to perform LBBAP using a SelectSecure 3830 lead.Radiofrequency atrioventricular node ablation was then performed, resulting in a complete atrioventricular block, with subsequent setting of the pacemaker to a VVIR mode with a resting frequency of 75 beats per minute.The patient presented to routine follow-up consultation 6 months later, complaining of recurring palpitations, without dyspnea, chest pain, or any other symptom. Physical examination was normal except for an irregular pulse.The patient’s 12-lead electrocardiogram  showed aPacemaker interrogation showed a persistent complete atrioventricular block, confirming the diagnosis of PVCs and absence of repermeabilization of the atrioventricular node, and a 13% burden of sensed ventricular complexes.An 80-year-old woman with a history of symptomatic persistent atrial fibrillation despite electrical cardioversion, surgical treatment of atrial fibrillation during a coronary bypass surgery, and optimal antiarrhythmic therapy underwent the implantation of a pacemaker followed by atrioventricular node ablation to control heart rate. Considering the risk of cardiac dyssynchrony consecutive to the pacemaker implantation with permanent stimulation, it was decided to perform LBBAP using a SelectSecure 3830 lead.Radiofrequency atrioventricular node ablation was then performed, resulting in a complete atrioventricular block, with subsequent setting of the pacemaker to a VVIR mode with a resting frequency of 75 beats per minute.Intermittent failure to capture occurred during immediate follow-up, leading to subsequent changing of the LBBAP lead after 2 days.The patient presented to routine follow-up 6 months later, without any cardiovascular symptoms. Physical examination was normal except for an irregular pulse.The patient’s 12-lead electrocardiogram  showed aPacemaker interrogation showed a persistent complete atrioventricular block, confirming the diagnosis of PVCs and absence of repermeabilization of the atrioventricular node.Given that it is a recent approach for cardiac stimulation and resynchronization therapy, long-term effects and complications of LBBAP are still being discovered, and these 3 similar cases highlight a previously unknown phenomenon upon these patients’ follow-up.We hypothesize that left Purkinje-related PVCs occurring in left bundle branch pacing could be related to a direct reentrant mechanism, as it has previously been described with bundle branch reentrant ventricular tachycardia during LBBAP.Another possible explanation may be the creation of local Purkinje injury during lead implantation and repositioning, constituting the substratum for PVCs. Left bundle branch pacing uses a transseptal approach, where the lead traverses the septum before reaching the left bundle branch area, which could cause local trauma to the Purkinje fibers.Guidance of left bundle branch pacing by PVCs has been well described,Another hypothesis could be that rate control achieved by atrioventricular node ablation could allow the presentation of PVCs that were so far suppressed by the rapid ventricular rate consecutive to atrial fibrillation.Of course, one cannot exclude a role of atrioventricular node ablation on occurrence of Purkinje PVCs; however, no data were found in the literature suggesting any link. Ablation was performed proximal to the His bundle, in the fast AV node pathway area, and premature complexes’ origins are distal to the bifurcation of the His bundle, specifically on the left bundle branch, which was targeted for pacing.These 3 cases highlight a potential risk of LBBAP-induced left-Purkinje PVCs. Although the underlying mechanism remains unclear, the similarities between the 3 patients and the consistent morphology with previous descriptions in other case reports stress the need for careful follow-up of LBBAP patients, both for screening for these PVCs and for assessing their long-term impact, especially on left ventricular systolic function. Therapeutic strategy and potential proarrhythmic risk remain unknown.In our experience of more than 100 LBBAP implantations, one-third of them having undergone atrioventricular node ablation, only 3 such cases occurred. Further descriptions and data are required to determine the prevalence of PVC following left bundle branch pacing, and cardiac imaging and electrophysiological studies may be helpful to precise the underlying mechanism.Patients with left bundle branch pacing and atrioventricular ablation may be exposed to left Purkinje-related PVCs. The underlying mechanism, prevalence, and long-term consequences need to be explored.


All term healthy neonates are screened for jaundice before hospital discharge as a standard clinical practice, but methods vary from clinical screening  to transcutaneous bilirubin (TcB) or total serum bilirubin (TSB) testing, depending on the setting.This systematic review of randomized and non-randomized studies evaluated the effectiveness of universal TcB and universal TSB screening at discharge compared to clinical screening alone for term healthy neonates. The outcomes were neonatal mortality, readmission for jaundice, severe hyperbilirubinemia (>20 mg/dL), jaundice requiring exchange transfusion, and bilirubin-induced neurological dysfunction (BIND). We searched MEDLINE via Ovid, EBM reviews, Embase, CINAHL, clinical trials databases, and reference lists of retrieved articles. Two authors separately evaluated the risk of bias, extracted data, and synthesized effect estimates using relative risk (RR) for randomized and odds ratio (OR) for non-randomized studies.For universal TcB at discharge, we included one randomized trial enrolling 1858 participants and four non-randomized studies enrolling 375 956 participants. No study reported neonatal mortality. The randomized trial suggested that universal TcB at discharge may decrease readmission for jaundice (risk ratio (RR) = 0.24, 95% confidence interval (CI) = 0.13 to 0.46; low certainty evidence) and severe hyperbilirubinemia , but the effect on jaundice requiring exchange transfusion  and BIND  was uncertain. Meta-analysis of non-randomized studies suggested that TcB may decrease severe hyperbilirubinemia (odds ratio (OR) = 0.25, 95% = CI 0.12 to 0.52; low certainty evidence) and jaundice requiring exchange transfusion , but the effect on readmission for jaundice was uncertain . For universal TSB, we included three studies from the United States enrolling 490 426 participants. The effect on severe hyperbilirubinemia , jaundice requiring exchange transfusion  and readmission for jaundice  was uncertain.Universal TcB at discharge may improve clinical outcomes for term healthy neonates. Evidence for universal TSB is uncertain.PROSPERO 2020 CRD42020187279. Neonatal jaundice characterized by yellowish discoloration of the skin caused by hyperbilirubinemia affects up to 60% of term neonates and 80% of neonates with a gestational age of 35 weeks or more in the first two weeks after birth . GloballIt is important to systematically evaluate all neonates for jaundice before they are discharged from hospital to identify neonates who might be at risk of developing severe hyperbilirubinemia, as detection may be delayed or missed once the neonate is discharged . While tWe conducted this systematic review to ascertain the effectiveness of universal TcB screening at discharge or universal TSB at discharge compared to clinical screening  for improving neonatal outcomes.This systematic review was registered in the PROSPERO database (PROSPERO 2020 CRD42020187279). We defined two study questions using the Patient, Intervention, Comparison, Outcome (PICO) framework:- Study question 1: neonates  without complications (P); universal screening for jaundice by TcB (I); clinical screening  (C); neonatal outcomes (O).- Study question 2: neonates  without complications (P); universal screening TSB (I); clinical screening  (C); neonatal outcomes (O)We included randomized (cluster-randomized or quasi-randomized) and non-randomized studies that compared universal TcB or TSB to clinical screening  in human neonates. We also planned to compare universal TSB with universal TcB if any study was found. Crossover trials were excluded. For both comparisons, ie, universal TcB vs clinical screening and universal TSB vs clinical screening, the intervention and the control groups could receive further investigations based on the initial assessment.Our review focused on term (≥37 weeks of gestation) healthy neonates, ie, neonates without any complications or illness during birth hospitalization. However, we did not exclude studies that enrolled late preterm neonates  or neonates with clinical risk factors for jaundice if they were otherwise well. Studies that enrolled neonates with visible jaundice or only preterm neonates were excluded.Universal TcB or TSB was defined as TcB or TSB done for all neonates before discharge from hospital, irrespective of the presence of a clinical risk factor for hyperbilirubinemia. The TcB could be done using any standard TcB device, and TSB could be done using any standard laboratory method.The clinical screening could be visual inspection alone or combined with assessment of risk factors. This could be followed by TcB or TSB if required. The registered protocol on PROSPERO specifies two different comparisons as visual inspection alone (comparison 1) and risk factor assessment (comparison 2). We combined these two comparisons into one as “clinical screening” as we did not identify any studies that considered risk factors alone for screening purposes to determine whether or not a TcB or TSB would be done.The studies must have reported at least one outcome of interest: neonatal mortality, hospital readmission for jaundice, severe hyperbilirubinemia (serum bilirubin level ≥20 mg/dL or 342.1 μmol/L), kernicterus or bilirubin-induced neurological dysfunction (BIND), jaundice requiring exchange transfusion, or neurodevelopmental outcome. We also recorded any reported side-effects of screening.An experienced information specialist (CS) designed a comprehensive search strategy in consultation with the review authors. This strategy covered MEDLINE via Ovid, Cochrane CENTRAL, Embase, and CINAHL, updated by December 31, 2021. Clinical trials databases, reference lists of retrieved articles, and grey literature, including related conference proceedings , were also searched for any eligible studies. The details of the search strategy are provided in the The databases were searched independently by two review authors (FK and SR). Any discrepancies between the two reviewers were resolved by a third reviewer (SG). Searches were limited to human studies. There were no language restrictions.Two authors independently extracted the data (FK and SR). Data extraction was done using a data extraction form that was designed and pilot tested by the review authors. The authors extracted information regarding design, methods, participants, interventions, outcomes, and treatment effects from each included study. We discussed disagreements until we reached a consensus. If data from the published reports were insufficient, their authors were contacted for clarification.Two review authors (SG and SR) independently assessed the methodological quality of the included studies using the Cochrane risk of bias tool for randomized studies (RoB 2.0) and the risk of bias in non-randomized studies of intervention (ROBINS-I) tool for non-randomized studies ,12. Any The meta-analysis was performed using RevMan (ver 5.4). Relative risk (RR) estimates for randomized and odds ratio (OR) estimates for non-randomized studies and their 95% confidence intervals (CI) were calculated when not provided by the study. If available, adjusted effect estimates provided by the studies were used. When the included studies provided only adjusted estimates without event rates in individual groups, the generic inverse variance method was used to calculate the pooled effect size and the participant numbers were entered manually where available.2I statistic. If the 2I statistic was <60%, we used the fixed-effect model; if the 2I was >60% or P was <0.1, we explored the possible causes of heterogeneity. If there was no obvious clinical heterogeneity, we used the random-effects model for meta-analysis. We used the GRADE pro software to calculate the certainty of evidence. [We examined the heterogeneity between study results by inspecting the forest plots and quantifying the impact of heterogeneity using the vidence.  We analySearch results are shown in The characteristics of the included studies are provided in Five studies with 377 814 participants were included in the comparison of universal TcB at discharge compared to clinical screening alone. One study was a randomized trial from South Africa which enrolled 1858 participants  and fourAll studies included a combined population of late preterm and term neonates. Three studies included neonates with GA≥35 weeks ,18,19 anAll studies performed TcB screening before discharge on all babies ,17,19,20The protocol for performing TSB following universal TcB screening varied across studies. One study obtained a TSB for all neonates in the “high-risk zone” based on an hour-specific TSB nomogram . One stuClinical screening comprised visual inspection and/or risk factor assessment. The studies specified this variably as visual inspection  , “clinicA summary of the risk of bias assessment in the five included studies is depicted in Figure S1 in the Three of the four non-randomized studies were at serious risk of bias ,18,20 beNone of the studies reported the outcome of neonatal mortality. Readmission for jaundice was reported by all five studies. The outcomes of severe hyperbilirubinemia and jaundice requiring exchange transfusion were reported by two studies and was measured during readmission in one study  and in tNone of the included studies reported the outcome of neonatal mortality.One randomized trial reported that universal TcB at discharge reduced readmission for jaundice . A meta-analysis of non-randomized studies  and non-randomized studies also found a reduction .One RCT reported that the effect was uncertain . However, the non-randomized study revealed that universal TcB at discharge reduced the proportion of neonates with jaundice requiring exchange transfusion .Only one randomized trial reported the outcome of kernicterus/BIND and the effect was uncertain  .Neurodevelopmental outcomes and side effects of screening were not reported in any of the included studies.None of the studies provided a subgroup analysis for any outcome by gestational age to allow separate analysis for term neonates only. The summary of findings tables are shown in For the comparison of universal TSB at discharge, two retrospective cohort studies ,21 and oAll three studies included neonates with gestational age ≥35 weeks (490 426 neonates). Two studies also had birthweight as an additional criterion. Neonates were included if birthweight was ≥2000 g in one study (358 086 neonates) and ≥2000 g if born at ≥36 weeks, or ≥2500 g if born at ≥35 weeks (31 059 neonates). Two studies included all neonates discharged from the well-baby nursery ,22 and oTwo studies evaluated universal pre-discharge TSB screening done at the time of obtaining the state-mandated newborn screening for inborn errors of metabolism ,22 whileOne historic cohort study  was condThe observational study  reportedThe second retrospective cohort study (358 086 neonates) was conducted in eleven hospitals ; data foTSB was measured using the 2,5-dichlorophenyldiazonium tetrafluoroborate (DPD) diazo method  in one study , the VitIn two studies, the comparison was clinical screening . Selective TSB was done  in one study , while tReadmission for jaundice was reported in two studies ,21. BhutA summary of the risk of bias assessment in the three included studies is depicted in Figure S2 in the None of the studies reported neonatal mortality. The meta-analysis  compared with the gold standard of laboratory serum bilirubin measurements . Clinica7 to 0.74A systematic assessment for jaundice at the time of discharge helps identify at-risk neonates, thus providing an opportunity for preventive/therapeutic interventions to be initiated in a timely manner with the potential to reduce the number of neonates needing readmission and/or developing neurotoxic levels of bilirubin. Hence, such an assessment is recommended as essential for discharge readiness . The impOur review highlights several important research gaps. There is no clear answer as to whether universal screening for hyperbilirubinemia using TcB or TSB reduces adverse outcomes such as acute and chronic encephalopathy or neurodevelopmental impairment, because of the low incidence of these morbidities and multiple factors concerning management and follow-up after the screening. There is a need for adequately powered trials comparing the effectiveness of various screening strategies on clinically relevant neonatal and infant outcomes.Our review systemically evaluates the effectiveness of common approaches for screening well neonates for jaundice at discharge for clinically relevant outcomes. We took a comprehensive approach and evaluated evidence from both randomized and non-randomized/observational studies using standard, methods.Our review has some limitations. First, while it is known that gestational age is an important risk factor, we could not perform a subgroup analysis for term healthy neonates  alone, aWe did not provide an evaluation of the economic impact of universal screening. It is clear that any screening program using TcB and TSB will have an associated cost and the burden of disease will be highest in low- and middle-income countries (LMICs) where health budgets are limited. The review highlights the importance of timely diagnosis to health care professionals and facilities so that resources can be utilized efficiently. This point was recognized as one of the recommendations in the 2015 Don Ostrow Trieste Yellow Retreat (DOTYR-1) session devoted to LMICs .Our findings are applicable to late preterm and term healthy neonates, ie, those who have had an uneventful birth hospitalization with no complications and are otherwise clinically well. Neonates who have visible jaundice were excluded, as they have a high probability of receiving TcB or TSB.Our review suggests that universal TcB screening at discharge should be part of the neonatal discharge readiness assessment for all facility births. Facilities implementing universal TcB screening should be able to obtain definitive testing  and provide appropriate treatment and follow-up for all neonates, with ongoing monitoring for quality of implementation. The effectiveness of universal pre-discharge TSB screening in improving neonatal outcomes is uncertain.


Epithelial ovarian cancer remains the most lethal female malignancy despite options for systemic therapy and the emergence of targeted therapies. Although initial response to therapy is observed, recurrence and ultimately chemoresistance result in overall therapeutic failure. This pattern has been evident with platinum therapy since the 1980s. Significant excitement surrounded the approval of poly (ADP-ribose) polymerase inhibition (PARPi) as a novel therapeutic option, especially with the advent of personalized medicine, but resistance has similarly developed to these treatments. Novel agents are constantly being sought, but if the obstacle of chemoresistance remains, the durability of responses will remain tenuous. Unraveling the multifactorial mechanisms of platinum and PARPi resistance is increasingly important as a therapeutic failure with current strategies is almost assured. Focusing greater efforts on expanding the current understanding of the complex nature of platinum and PARPi chemoresistance has tremendous potential to improve clinical outcomes. Platinum-based therapy has been the cornerstone of EOC treatment for decades, but the majority of patients relapse within two years, and eventual platinum resistance is accompanied by an extremely poor prognosis,3. Platinum-refractory disease is defined as a persistent or progressive disease while receiving platinum-based chemotherapy or within four weeks of therapy, and platinum resistance is defined as cancer recurrence or progression within six months of platinum therapy. The median survival in platinum-resistant disease is only 12 months, underscoring the need to identify novel therapies but also to understand and overcome the complex mechanisms of chemoresistance.Epithelial ovarian cancer (EOC), primarily high-grade serous carcinoma (HGSOC), remains the leading cause of death from gynecologic cancers primarily due to the advanced stage at the time of diagnosis and the inherent difficulty of treating tumors that become resistant to chemotherapy over varying amounts of time. Surgical cytoreduction and platinum-based chemotherapy have been the mainstay of ovarian cancer treatment since the 1980s. Platinum cytotoxicity results from its ability to cause an accumulation of deoxyribonucleic acid (DNA) double-strand breaks and cell death via the formation of intra-strand and inter-strand adducts which activate cellular DNA damage response (DDR) pathways, which inhibit replication and transcription of DNA, inducing cell cycle arrest and apoptosis. Several clinical trials have demonstrated the impressive benefit of PARPi therapy, especially in patients who have responded to platinum-based therapy,7. This might be attributable to the high prevalence of tumors with homologous recombination deficiency (HRD), which is found in approximately 50% of all ovarian cancers. BReast CAncer gene (BRCA1/2) germline deficiency accounts for approximately 20% of these cases. Somatic BRCA mutations result in HGSOC phenotypes and platinum chemotherapy responses similar to germline BRCA mutation carriers and are referred to as HGSOC with “BRCAness”. BRCA variants, either germline or somatic, lead to an increased susceptibility to DNA double-strand breaks. PARPi elegantly capitalizes on synthetic lethality when PARP inhibition and HRD are combined to cause apoptosis of cancer cells.The advent of poly (ADP-ribose) polymerase inhibition (PARPi) as a novel therapeutic option approved for EOC in 2014 presented significant excitement and marked the birth of personalized medicine in EOC. Poly (ADP-ribose) polymerases (PARP) are a family of proteins with several roles that include DNA repair  and DNA mismatch repair), apoptosis, chromatin remodeling and the stress response,9. A specific definition for PARPi resistance has not yet been developed as exists for platinum-based chemotherapy, and it remains to be seen if tumors are resistant to all PARPi once resistance is developed to a single PARPi.Resistance to platinum therapy is strongly predictive of resistance to PARPi therapy consistent with overlapping biologic mechanisms of susceptibility and resistanceIn this commentary, we will explain some of the most clinically relevant tumor biology contributing to platinum and PARPi resistance, two of the most significant therapies in use currently for EOC, as well as review future directions.. There are several mechanisms, both intrinsic and acquired, that contribute to platinum chemoresistance. Platinum compounds may undergo decreased uptake into cells, increased efflux, or increased inactivation. For example, overexpression of the adenosine triphosphate-binding cassette (ABC) family of transporters, such as P-glycoprotein or multidrug resistance-related proteins (MRP1), affects the efflux of chemotherapeutic drugs. Although the exact mechanism of action is not clear, high levels of ABC subfamily A member 1 expression have been found to correlate with poor progression-free and overall survival in serous EOC. Key proteins that signal DNA damage to cell-cycle checkpoints and DNA repair pathways include: ataxia-telangiectasia mutated (ATM), ATM-and RAD3-related, DNA-dependent protein kinases. These key proteins sense DNA damage and initiate repair signaling cascades by phosphorylation of key repair proteins: BRCA1, checkpoint kinase 1 (CHK1), checkpoint kinase 2, tumor protein p53 (P53) and RAD17. Cellular mechanisms that assist in the repair of DNA include base excision repair for single-strand breaks (SSBs); nucleotide excision repair (NER) for the repair of bulky adducts (such as observed with platinum therapy); mismatch repair (MMR) for mispaired bases; homologous recombination (HR) repair for double-stranded breaks (DSBs), intra-strand and inter-strand crosslinks; non-homologous end-joining (NHEJ) for DSB; or microhomology-mediated end joining for the repair of DSBs. Once platinum cytotoxicity has occurred and adducts have begun to form, cells may still be able to thwart its effects by acquiring the ability to repair platinum-induced DNA adducts via counteraction of the cell’s DDR response. The DDR response is an essential network of proteins that sense, signal and/or repair DNA damage to maintain genomic integrity and stability within the cell. Cells that have acquired platinum resistance subvert the normal DDR responses and instead demonstrate increased ability to initiate repair signaling, activate checkpoints to slow progression and allow repair, increase the pace of adduct repair or even develop the ability to tolerate DNA adducts without resorting to apoptosis,14. When DNA damage is too severe for repair, apoptosis is triggered. This process allows NER to recognize DNA crosslinks and converts the crosslink to a DNA double-strand break. HR is then required to repair the double-strand break to prevent apoptosis.The NER and HR repair pathways work very closely together. The NER pathway recognizes and removes bulky helix-distorting crosslink lesions via a step-wise process: damage recognition, unwinding of the DNA locally around damage, incision of damaged DNA by endonucleases, and DNA resynthesis and ligationin vitro, supporting the importance of NER in the development of platinum chemoresistance,18,19. Specifically, the excision repair cross-complementation group 1 (ERCC1) protein plays a key role in nucleotide excision repair. Dimerization of ERCC1 with xeroderma pigmentosum complementation group F (XPF) enables excision and repair of bulky cisplatin lesions in damaged DNA. Overexpression of proteins in the NER pathway, including ERCC1, is associated with platinum resistance, likely via the ERCC1-XPF endonuclease,20.In preclinical trials, enhanced NER in ovarian cancer models has been associated with increased cisplatin resistance . P53 expression specifically leads to growth phase 1 (G1) / synthesis (S) checkpoint deficiencies and cell-cycle dysregulation, subsequently placing greater stress on the growth phase 2 (G2) / mitosis (M) checkpoint for survival. Wee1 kinase inhibits activation of Cyclin-dependent kinases 1 (CDK1) and CDK2, making it a key cell cycle regulator of the G2/M transition. Alterations in Wee1 kinase may have implications for chemoresistance. Additionally, P53 expression, common in HGSOC, promotes tumorigenesis as well as drug resistance via inhibition of apoptosis. Inhibited apoptosis contributes to proliferation and metastasis.Although the majority of EOC responds to platinum therapy, even if only for a limited time, many do not exhibit any durable response to platinum therapy. Mechanisms of such intrinsic chemoresistance include proficient DNA repair, cyclin E1 (CCNE1) amplification, and mesenchymal or proliferative molecular subtypes. Approximately 20% of EOC cases have CCNE1 amplification, which are associated with primary resistance to platinum. BRCA reversion mutations have been identified in progression biopsies as well as cell-free DNA (cfDNA). cfDNA has shown polyclonality of multiple reversion mutations within a single patient when under pressure from treatment. One mutation that has demonstrated restoration of DNA repair is BRCA1-Δ11q. Patients with BRCA1-Δ11q demonstrated decreased sensitivity to both cisplatin and PARPi. BRCA reversion mutations have been identified in 13% of patients with platinum-refractory disease and 18% of patients with platinum-resistant disease. Patients with BRCA reversion mutations experienced decreased progression-free survival when undergoing treatment with rucaparib. The initial strength of response to PARPi has been shown to correlate with the severity of eventual tumor resistance.The current understanding of the mechanism of PARPi resistance centers around Darwinian escape. Darwinian escape refers to an acquired secondary somatic mutation to restore HR in BRCA 1/2 (reversion mutations),26. Chen et al. demonstrated that cisplatin-resistant cancer cells show increased intracellular hypoxia and decreased glucose uptake suggesting that platinum resistance might stem from alterations in glucose metabolism. Altered angiogenesis is another hallmark of intra-tumor vessels which also contributes to hypoxia, poor drug delivery, and chemoresistance.Numerous studies have demonstrated the critical role of hypoxia in the tumor microenvironment and its association with platinum resistance via signaling pathways in DNA damage, mitochondrial activity, apoptosis autophagy, and drug efflux,29. Platinum chemotherapy is also thought to influence anti-tumor immunity. Increased infiltration of immunosuppressive Cluster of Differentiation 163-positive macrophages and increased infiltration of regulatory forkhead box P3-positive T cells have favored tumor growth,30-32. In contrast, the presence of tumor-infiltrating lymphocytes is positively correlated with survival,33. Data on immune checkpoint therapy in EOC has been contradictorily reflecting an incomplete understanding of the key regulators and pathways. Immunotherapy may yet play an important role in EOC.Cancer-associated fibroblasts, tumor-associated macrophages, and cancer stem cells have all been proposed influencers of prognosis and chemotherapy resistance. Stromal activation with extensive desmoplasia has been associated with poor clinical outcomes and acquired treatment resistance,35. Elevated cytokines and adipokines in the ascitic fluid are thought to protect malignant cells from chemotherapy-induced apoptosis, including via lysophosphatidic acid signaling and prostaglandin E2 -mediated GFTR transporter upregulation. The metabolism of tumor cells is intricately intertwined with all cells of the microenvironment. Tumor cells have demonstrated an amazing ability to metabolically adjust to changes in their environment, as well as influence the metabolic function of neighboring cells for their own purposes,35,36. Additionally, the omentum and cell metabolism are thought to play a pivotal role in cancer progression and chemoresistance. The omentum is a favored site for metastasis due to EOC’s ability to use fatty acids to initiate and sustain peritoneal metastasis; in addition, it may also participate in ascites formation. Stem cell pathways have recently been recognized as an important mediator of chemoresistance. CSCs have improved methods of chemotherapy removal from the cell, including the ABC cassette and drug transporters. Tumors containing heterogeneous cancer cells are linked to progression as they are more likely to undergo selection towards a population of drug-resistant tumor cells with treatment. CSCs are aided by their microenvironment and stimulated by hypoxia-inducible factors. Phosphoinositide kinase (PI3K) has an important role in apoptosis for maintaining stem cell “stemness” and drug resistance. Notch signaling and Wnt/beta-catenin are important in CSCs signaling pathways and may be useful targets. CSCs are also able to grow in spheres and expand as sphere-like cellular aggregates more easily than other populations of cells. The ability to treat cancer stem cells is of particular importance since these cells can remain in patients with seemingly no evidence of disease or lead to metastasis.Cancer stem cells (CSCs) are theorized as a population of cells capable of self-renewal and repopulation following cancer treatment that may cause tumor initiation and metastasisChemoresistance evolves over time as a response to the selective pressure of therapy. The multiple mechanisms of resistance are complex and not fully understood, but strategies to overcome chemoresistance are being developed. These methods include exploration of methods to improve drug delivery; identification of potentially useful biomarkers; identification of molecular targets; and exploitation of tumor weaknesses using modulation of the cell cycle, tumor microenvironment, or cellular metabolism. Combination therapies may improve this exploitation of tumor weaknesses.,40. Layer-by-layer nanoparticles have also been used to deliver cisplatin and a PARPi to mice, with improved bioavailability, cytotoxicity, and systemic toxicity compared with conventionally administered medication. Natural compounds including curcumin and piperine are being evaluated to attempt to induce G2/M phase arrest, caspase activation, the PI3K pathway (piperine), and apoptosis and phosphorylation of p53 (curcumin). Improved drug delivery could also combat chemoresistance. Nanotechnology is being used to investigate the ability of nanoparticles to improve targeted treatment, including the encapsulation of cisplatin with dendrimers to aid in cell killing. Improved understanding of why some patients with BRCA pathogenic variants do not respond to PARPi, and why some patients with no known BRCA mutation respond to PARPi treatment could be important for combatting drug resistance. Biomarkers that predict treatment success would be of significant benefit if they allowed improved treatment selection. However, our understanding of biomarkers that would be useful in guiding treatment selection is limited. A number of genes and proteins have been identified in patients with chemoresistance or poor prognosis and have yet to be evaluated in clinical trials to guide treatment. One gene amplification, 19q12, is associated with chemoresistance and has been identified in 20% of ovarian cancer patients,40. MMR deficiency has also been implicated in chemoresistance, but the correlation is controversial,19,41.A study of patients with durable responses may be useful for identifying biomarkers, especially patients with HR proficiency who have good responsesin vitro studies in non-small cell lung cancer by Altaha et al. concluded that high levels of ERCC1-mRNA and/or ERCC1 protein were associated with resistance to platinum compounds. Despite the correlation between ERCC1 overexpression with platinum resistance and ERCC1 under expression with platinum sensitivity, translating ERCC1 as a predictive biomarker for response to platinum-based therapy in clinical trials has been challenging. ERCC1 has been investigated as a biomarker in both adrenocortical carcinomas and advanced non-small cell lung cancer and did not offer prognostic or treatment selection benefits,45. Continued study of ERCC1 and the NER pathway is needed.Based on the leading roles played by ERCC1 and XPF in the NER pathway, they have been promising prospects as biomarkers for platinum-based therapy. A meta-analysis of retrospective RAD51C and RAD51D, and in vitro studies have demonstrated loss of TP53 binding protein 1,46. Studies of TP53 vary regarding its utility as a marker in platinum resistance, but it may be helpful in treatment planning. Pump P-glycoprotein (P-gp) expression, which is related to drug efflux and multidrug resistance, has also been implicated in PARPi resistance,48. CSC markers of Bmi-1, Nanog and Oct 4 with elevated stem cell factor and c-Kit levels indicated chemoresistance as well. Other proteins indicating resistance and poor prognosis include Notch3 and LGR5; CD24 correlates with poor prognosis, chemoresistance, metastasis, and recurrence; CD44+/CD117+ cells were associated with chemoresistance; CD133+ cells showed cisplatin resistance, and ALDH1A1 was associated with poor survival and drug resistance,49. AT-rich interaction domain 1A inactivation or loss of expression is also correlated with poor overall survival in patients receiving platinum. Micro ribonucleic acids (miRNAs), including let-7 g, miR-98-5p, miR-622 as well as others, have been associated with platinum and/or PARPi resistance.Patients with PARPi resistance have been found to have reversions in . Serial assessments would enable real-time patient assessment and comparison during therapy at the onset of resistance to therapy, which may increase our understanding of chemoresistance.Newer technology in tumor surveillance may also be critical to the understanding of tumor chemoresistance and the discovery of biomarkers. Liquid biopsies may offer a unique opportunity for real-time tumor molecular profiling. Liquid biopsies enable the analysis of circulating tumor cells, circulating tumor DNA, circulating mRNA, and tumor-derived extracellular vesicles that are shed from primary tumors into the peripheral blood. Absolute copy number profiles have been generated using primary and relapsed HGSC samples. Macintyre et al. identified seven copy number signatures that were stable between diagnosis and disease relapse, indicating that copy number signatures at diagnosis may predict overall survival and platinum resistance. Different mutational processes generate unique combinations of mutation types, termed mutational signatures. The Catalogue of Somatic Mutations in Cancer (COSMIC) has revealed many mutational signatures across the spectrum of human cancer types. Analysis of COSMIC mutational signatures in ovarian cancer reveals a prevalence of signature 1B.Other possible areas of investigation involve the utilization of next-generation sequencing to aid the discovery of predictive signatures. Four molecular subtypes of HGSOC have been described and validated by the Cancer Genome Atlas Research Network study.Epigenetic modifications are mechanisms that alter the expression of a gene but do not change the DNA sequence. These modifications help to regulate normal genome functioning. Epigenetic modifications may also be contributing to chemoresistance. Identification of epigenetic changes in chemoresistant EOC may allow for the advanced development of epigenetic modulating drug therapy. Current agents such as demethylating agents, histone deacetylase inhibitors, and microRNA-targeting therapies have shown preclinical promise,58. PARPi do have different potencies due to the degree of PARP trapping; clinical implications have yet to be seen. Additionally, re-examining the definition of platinum sensitivity and resistance may be needed.Defining PARPi resistance and evaluating the utility of alternating PARPi therapy if resistance has developed to one PARP remains to be seen but may be answered by the OReO trialet al. of breast cancer patients with and without BRCA mutations and with resistance to both cisplatin and olaparib, a benefit of combined therapy with olaparib and cisplatin was identified. Interestingly, the combination treatment was not helpful in patients whose disease was still sensitive to either treatment. A similar investigation could be considered in EOC patients as well. Niraparib has been investigated in combination with carboplatin and gemcitabine for patients with unresectable or recurrent platinum-sensitive ovarian cancer and showed a 57% radiographic response rate. Cisplatin-resistant ovarian cancer cells (C13) were treated with a PARPi, 3-aminobenzamide by Zhang et al. Cellular proliferation was inhibited more when treated with cisplatin and increasing doses of PARPi, pointing to chemosensitization. Additional studies investigating novel DDR-targeting agents and combination treatment approaches are underway.Combination therapies of PARPi and platinum together, or the addition of another agent to combat chemoresistance when using one or the other, may allow circumvention of treatment resistance. In a study by Gajan . This treatment combination is under further investigation with the OVC2 trial,63. One promising target for therapeutics to combine with PARPi is mesenchymal-epithelial transition factor (c-Met), a receptor tyrosine kinase, since the high expression is associated with a poor prognosis. This biomarker and therapeutic target have been linked to PARP resistance and HR restoration. CDK have also been proposed as targets since they control cell cycle progression and DNA damage control. Loss of CDK inhibition impairs BRCA function (BRCAness). PI3K inhibitors have been proposed as methods to extend the use of PARPi and are under investigation,64,65. Other therapies that have been trialed include PARPi with alkylating agents, topoisomerase I inhibitors, WEE1 kinase inhibitors, PI3K inhibitors, radiation, immunotherapy, and DNA methyltransferase inhibitors. PARPi with topoisomerase I inhibitor allows inhibition of TOP1-PARylation, inhibition of homologous recombination and stimulation of NHEJ plus inhibition of tyrosyl-DNA-phosphodiesterase I. Clinical investigations of this combination have not been completed. However, promising combination treatments to overcome PARPi or platinum resistance have not been identified.As targetable pathways have been implicated in chemoresistance, translational researchers have also been searching for immunotherapies and molecular targets to use as combination therapies to improve the cytotoxic effect of therapy. Anti-angiogenesis with cediranib in combination with olaparib has been investigated with efficacy that varied by mutation identified following PARPi progression, with poorer outcomes identified for patients with HRD reversion mutations and ABCB1 upregulationEOC is a disease marked by frequent relapses and responses to therapy before the eventual development of chemoresistance. Chemoresistance remains a steadfast obstacle to improving EOC survival. Platinum, the mainstay of EOC treatment, is limited by almost ubiquitous platinum resistance. While anti-angiogenic therapy and PARPi are promising new treatments, resistance has already been observed. The heterogeneity of EOC allows it to adapt in response to treatment and confounds attempts to identify clinically meaningful biomarkers and targets. Tumors constantly evolving with time and treatment seem to naturally develop resistance. . EOC, given its inherent heterogeneity, may require an equally malleable treatment approach: the serial integration of genomic, epigenomic, metabolomic, and immunogenic study at diagnosis and at each recurrence to optimize therapy. It would require a significant change in clinical practice and greater investment in bioinformatics, but it may not be possible to conquer all the nuances of EOC without it.In some cancers, real-time collection of circulating tumor DNA is a reality that has enabled the characterization of drug response for tumors along with multiple time points


However, the reported location and direction of the observed white matter changes in mild traumatic brain injury are variable, likely attributable to the inherent limitations of the white matter models used. This cross-sectional study applies an advanced and robust technique known as fixel-based analysis to investigate fibre tract-specific abnormalities in professional Australian Football League players with a recent mild traumatic brain injury. We used the fixel-based analysis framework to identify common abnormalities found in specific fibre tracts in participants with an acute injury . We then assessed whether similar changes exist in subacute injury . The control group was 29 neurologically healthy control participants. We assessed microstructural differences in fibre density and fibre bundle morphology and performed whole-brain fixel-based analysis to compare groups. Subsequent tract-of-interest analyses were performed within five selected white matter tracts to investigate the relationship between the observed tract-specific abnormalities and days since injury and the relationship between these tract-specific changes with cognitive abnormalities. Our whole-brain analyses revealed significant increases in fibre density and bundle cross-section in the acute mild traumatic brain injury group when compared with controls. The acute mild traumatic brain injury group showed even more extensive differences when compared with the subacute injury group than with controls. The fibre structures affected in acute concussion included the corpus callosum, left prefrontal and left parahippocampal white matter. The fibre density and cross-sectional increases were independent of time since injury in the acute injury group, and were not associated with cognitive deficits. Overall, this study demonstrates that acute mild traumatic brain injury is characterized by specific white matter abnormalities, which are compatible with tract-specific cytotoxic oedema. These potential oedematous changes were absent in our subacute mild traumatic brain injury participants, suggesting that they may normalize within 12 days after injury, although subtle abnormalities may persist in the subacute stage. Future longitudinal studies are needed to elucidate individualized recovery after brain injury.Sports-related concussion, a form of mild traumatic brain injury, is characterized by transient disturbances of brain function. There is increasing evidence that functional brain changes may be driven by subtle abnormalities in white matter microstructure, and diffusion MRI has been instrumental in demonstrating these white matter abnormalities  et al. report that acute sports-related concussion is characterized by tract-specific abnormalities, which can be detected using fixel-based analysis of diffusion MRI data. These tract-specific changes are not evident in the subacute stage of injury, and may be compatible with cytotoxic oedema in acute concussion.Mito   Investigating subtle changes to WM fibre structures in vivo could thus be valuable in the diagnosis and management of mTBI.Over the past two decades, there has been rapidly growing interest in the short- and long-term pathophysiological effects of sports-related concussion, in large part, prompted by affected high-profile athletes and forced retirements across numerous different sporting codes. Sports-related concussion, or mild traumatic brain injury (mTBI), is characterized by a complex cascade of neurometabolic events, which can impact brain function for days to weeks and months.in vivo, and in particular, diffusion-weighted imaging (DWI) has provided a means to non-invasively examine WM architecture. A particular form of DWI, known as diffusion tensor imaging (DTI), has been widely adopted by researchers to assess subtle WM abnormalities in mTBI participants. DTI studies have identified abnormalities at various time points following sports-related mTBI.11–16 These studies have typically assessed changes to metrics such as fractional anisotropy (FA) and mean or radial diffusivity, which in more severe cases of TBI have been used as an in vivo proxy for traumatic axonal injury.17 However, in mTBI, the subtle nature of neurophysiological effects means that WM tract changes are challenging to assess. There has correspondingly been substantial variability in the direction of detected DTI-based changes, as well as the spatial location of these abnormalities across studies.18–22To this end, advances in human neuroimaging have resulted in an improved capability to examine tissue microstructure 23 In the presence of such crossing fibre structures, the same underlying pathologies could drive both increases and decreases in DTI-based metrics.24–27 For example, a loss of axons could result in decreased FA; however, in the presence of unaffected crossing fibre structures, loss of axons could result in increased anisotropy in that region.27 Indeed, in the context of mTBI, both increases29 and decreases30–32 in FA have been reported. These conflicting findings, though they have been suggested to reflect the same pathophysiological changes,11 can be difficult to interpret biologically, and as such, researchers have stopped short of recommending DTI as a diagnostic biomarker in the clinical setting.A potential explanation for the inconsistencies across DTI studies may stem from the limitations of the DTI model itself. While DTI is sensitive to subtle abnormalities in WM microstructure, it is unable to model complex or crossing fibre populations, which account for up to 90% of WM imaging voxels.33–35 one recent DWI analysis technique known as fixel-based analysis (FBA)36 also enables the quantification of changes to specific fibre populations within voxels. FBA can be used to estimate: (i) differences in the density of fibres within a fibre bundle, (ii) differences in fibre bundle cross-section (FC) and (iii) differences arising from a combination of density and cross-sectional changes.37 By performing statistical analyses at each WM ‘fixel’ (specific fibre population within a voxel), FBA can ascribe detected changes to specific WM tracts and does not suffer from interpretability issues that can arise in crossing fibre populations when using DTI.38 Moreover, even in the absence of potential confounding factors that arise due to crossing fibre populations, FBA metrics can offer greater biological interpretability, which could be highly valuable in the clinical setting in mTBI.Higher-order DWI models overcome some of the limitations inherent to the DTI model and may be critical for detecting subtle WM abnormalities in mTBI without being confounded by the presence of crossing fibre structures. While several models can estimate multiple fibre orientations within voxels,In this cross-sectional study, we applied FBA to investigate fibre tract-specific abnormalities in 29 professional Australian Football League (AFL) players with a recent mTBI. These professional players were available to participate in the study only when they were unable to return to training and play. This was either after acute injury before return-to-play, or sub-acutely when they had persistent symptoms that prevented them from return-to-play. This study aims to investigate whether sports-related mTBI is characterized by abnormalities within specific WM fibre tracts at these acute and subacute stages. We hypothesized that individuals with acute mTBI would exhibit tract-specific fibre density (FD) abnormality and that these abnormalities would be less pronounced in participants at the subacute phase of injury. Additionally, we investigated the association of these fibre-specific abnormalities with time since injury and cognition in mTBI, hypothesizing a decline of abnormality with greater time since injury and more apparent abnormality in those with greater cognitive symptomatology.n = 38) were recruited from professional AFL teams in Australia between 2014 and 2019. AFL is a sport played at speed and with a high incidence of concussion, of up to 17.6 concussions per 1000 player hours.39–41 All participants were recruited after having suffered a suspected mTBI (concussion). Concussion was diagnosed by experienced team doctors who were present at the time of injury. AFL team doctors have a consistent approach to the diagnosis and management of concussions due to ongoing research and education programmes over the past 20 years.42Male participants . Anatomical MRI scans were reviewed by a neurologist (G.D.J.). Participants were also excluded if they exhibited a focal injury or more severe TBI resulting in intracranial bleeding . Participants were also excluded from the study if their MRI scan was more than 3 months after their concussion (n = 3), if they had been scanned using a different MRI scanner type or head coil (n = 1), or if their MRI acquisition was incomplete (n = 2).All concussed participants were assessed at the time of injury with the Sports Concussion Assessment Tool (SCAT3), and a sideline video review was used where available.n = 14), while those whose MRI scan was >12 days since concussion were categorized into a subacute mTBI group (n = 15). Although acute concussive injury is commonly defined as injury within a 48 h period,2 researchers use various time periods to describe acute mTBI across studies.22 Here, we use a cut-off period of 12 days in line with the current AFL protocol that mandates a 12-day rest period following mTBI.44In total, 29 male professional AFL footballers were included in the study. These 29 mTBI participants were categorized into two groups, based on the time delay from the concussion until MRI scan. Those participants who had their MRI scan ≤ 12 days since concussion were categorized into an acute mTBI group . For each mTBI participant, a male control participant was selected who matched the mTBI participant in age.Healthy control participants were recruited for the study, or selected from previously acquired DWI control data obtained at our institute (All participants provided written informed consent before participating in the study. The study was approved by the human research ethics committees at the University of Melbourne (ID: 0830367) and at Austin Health (ID: 49573/2019 and H2012/04475).All participants underwent an MRI scan at the Florey Institute of Neuroscience and Mental Health, which included high angular resolution DWI acquisition.b = 3000 s/mm2) and at least 1 b = 0 image. A reverse phase-encoded b = 0 image was acquired in all cases to correct for B0-field inhomogeneities.MRI data were acquired at 3 T on a Siemens Skyra with a 20-channel head coil receiver . Echo planar imaging DWI data were acquired with 60 axial slices, TR/TE = 8400/110 ms, 2.5 mm isotropic voxels, 64 diffusion-weighted images . Susceptibility-induced off-resonance fields were estimated using the different phase-encoded b = 0 images,49 after which gross subject movement and eddy-current-induced distortions were estimated.50 The quality of the diffusion data sets was assessed using eddy QC tools.51 Estimates of subject motion obtained from eddy QC were used to determine whether groups differed in motion. Bias field correction was then performed,52 and diffusion-weighted images were finally upsampled to a voxel size of 1.3 mm2 using cubic b-spline interpolation.53Pre-processing of diffusion-weighted images included denoising54 with group-averaged response functions for WM, grey matter and CSF, using MRtrix3Tissue (http://3Tissue.github.io). Joint bias field and intensity normalization were then performed.Following these pre-processing steps, fibre orientation distribution (FOD) functions were computed using single-shell, 3-tissue constrained spherical deconvolution,55 FOD images from all subjects were then registered to the unbiased template image using FOD-guided non-linear registration.56A study-specific population template image was generated using FOD images from a subset of participants who were randomly selected from the study cohort. FOD images from 40 participants  were used to generate a population template image using an iterative registration and averaging approach.57A whole-brain tractogram was generated using probabilistic tractography on the population template. Twenty million streamlines were generated, which were subsequently filtered to 2 million streamlines to reduce reconstruction biases using the SIFT algorithm.36 whereby the term ‘fixel’ refers to a specific fibre population within a voxel. In brief, this involved computing measures of apparent FD, FC and a combined metric of fibre density and cross-section (FDC) for each subject at each WM fixel in template space.Abnormalities in WM pathways were assessed using the FBA framework,53 whereby a quantitative measure of FD can be derived from FOD images, as the integral of the FOD along a given direction is proportional to the intra-axonal volume of axons aligned in that direction. FD values for each subject at each fixel were assigned to the template fixel mask so that FD could be compared across groups in corresponding fixels. FC was computed for each fixel by using the non-linear warps to compute the change in FC required to normalize each subject to the template image. While the FD measure provides insight into the intra-axonal density of fibre pathways in a given direction , the FC measure estimates changes to the spatial extent occupied by a fibre bundle .36 Finally, the FDC metric combined both sources of information (FD and FC), to estimate both density and cross-sectional changes in specific WM pathways.FD was computed according to the apparent FD framework,59 These tasks are designed to assess psychomotor function, decision-making, working memory, and learning, respectively. Normalized scores from these tests based on neurologically normal healthy individuals60  were used in subsequent regression analyses to examine the relationship between fibre-specific changes and cognition.Cognitive testing was performed at the time of the MRI scan using CogSport, a computerized cognitive test battery . The battery comprised four tasks: simple reaction time, complex reaction time, one-back and continuous learning, which have previously been shown to be sensitive to the cognitive effects of concussion in sport.61 Family-wise error (FWE)-corrected P-values were assigned to each fixel using non-parametric permutation testing over 5000 permutations.62 Statistical significance was set at an FWE-corrected P-value < 0.05.Whole-brain FBA was performed to compare measures of FD, FC and FDC in the three groups of interest . Statistical comparisons of these fixel-based metrics were performed between groups at each WM fixel using a general linear model, by performing the following group-wise comparisons: (i) acute mTBI versus controls; (ii) subacute mTBI versus controls; and (iii) acute mTBI versus subacute mTBI. Age and intracranial volume were included as nuisance covariates. Connectivity-based smoothing and statistical inference were performed using connectivity-based fixel enhancement, using 2 million streamlines from the template tractogram and default smoothing parameters .post hoc tract-of-interest analyses, to examine if the observed fixel-based differences were associated with clinical measures.The fixels that exhibited significant differences in our whole-brain FBAs were selected for exploratory post hoc analyses with clinical measures, there were five fixel clusters selected: the genu, splenium and body of the corpus callosum, left frontal WM cluster, and left parahippocampal/isthmus WM cluster. These fixel clusters were selected from significant results from whole-brain FBA: between the acute mTBI and control groups for the genu and left parahippocampal/isthmus cluster; and between the acute and subacute mTBI groups for the remaining three fixel clusters . The mean FD, FC and/or FDC values were computed within each of these five tract clusters, for the fixel-based metrics that exhibited a significant difference upon whole-brain FBA . Given that post hoc regression analyses were performed only in the mTBI participants, we then expressed FD, FC and FDC values as a percentage change in the mTBI participants from the control group mean.For post hoc linear models were performed within the acute mTBI cohort, to examine the relationship between the mean FD/FC/FDC in the five fixel clusters with time since injury. The intracranial volume was included as a covariate in these analyses , and Bonferroni correction was used to correct for the five tract comparisons.Exploratory We then explored the relationship between the mean FD/FC/FDC in the five fixel clusters and cognitive scores across the mTBI cohort (both acute and subacute mTBI). Here, linear models were performed to examine the relationship between the mean fixel-based metrics within each of the five fixel clusters and normative scores  for the four cognitive tests . The intracranial volume was again included as a covariate in these analyses, and the Bonferroni correction was used to correct for the five tract comparisons.post hoc statistical analyses were performed in R (version 3.6.3).All The data that support the findings of this study are available upon reasonable request from the corresponding author. The data are not publicly available as they include participant data that could compromise the privacy of participants.Participant demographics are available in Athletes in the acute and subacute mTBI groups had comparable years of professional sporting career and did not differ substantially in CogSport cognitive test measures at the time of MRI scan .P-value. While increased FDC was observed in the acute mTBI group when compared with both the control and subacute mTBI groups, predominantly in callosal fibre structures, there was no evidence of decreased FDC in the acute mTBI group when compared with the other groups. In contrast, we did not observe any significant increases in FDC in the subacute mTBI group when compared with controls or acute mTBI. Some fibre structures appeared to have lowered FDC in the subacute mTBI group ; however, these did not survive FWE correction.P-value < 0.05). A significant increase in FDC was also observed in the acute mTBI group compared with controls in the genu and body of the corpus callosum  to those with a longer delay since concussion . Fixels that exhibited significant changes in the acute mTBI group when compared with either the control or subacute mTBI groups were grouped into five tract clusters. These tracts-of-interest are shown in Cognitive data were available for 27 mTBI participants, while they were unavailable for 2 participants, who were excluded from these analyses. We did not observe any significant associations between mean fixel-based measures in the tracts of interest with cognitive test scores see . ScatterIn this study, we applied advanced diffusion MRI methodology to investigate fibre tract-specific WM abnormalities in professional athletes after an mTBI. The major findings of our work were that: (i) participants with acute mTBI exhibit abnormalities in selected fibre tracts, which can be interpreted as WM tract-specific cytotoxic oedema and (ii) these fibre-specific abnormalities do not seem to persist into the subacute stage beyond 12 days after injury, even when symptoms may persist.Abnormalities were observed in specific fibre pathways in acute mTBI participants when compared with control participants in this study, as measured by increases in FDC. Significant changes occurred in the left posterior parahippocampal WM, and the genu and body of the corpus callosum. Moreover, when comparing acute mTBI with subacute mTBI participants, FDC were also found to be elevated in additional WM structures: within the splenium of the corpus callosum and left frontal WM of the superior longitudinal fasciculus.64 despite variability in other neuroanatomical locations involved.20 Indeed, callosal structures and midline WM tracts appear to be preferentially vulnerable to traumatic axonal injury, as has been demonstrated in post-mortem studies,6 animal models65 as well as laboratory reconstructions of sports-related concussions.66The location of these tract-specific WM abnormalities is in line with the body of mTBI literature using DTI, in which certain fibre structures like the corpus callosum have consistently been implicated,67 and TBI more broadly69 that suggest there is greater left hemisphere abnormality than right. The same left hemisphere fibre tracts that have been shown to exhibit abnormalities in DTI studies in mTBI have also shown leftward asymmetry in healthy individuals,71 whereby higher WM integrity has been reported. Some have hypothesized that this asymmetry may render these WM regions more vulnerable to sports-related mTBI.67 Alternatively, it may be that left-sided injury with verbal disturbance is more often diagnosed as concussion, and overrepresented in these cohorts. Interestingly, in a recent case study from our cohort, increased water content (MRI-T2 relaxometry) was observed within the left frontal WM, which we suggested reflects selective vulnerability to post-concussive neuroinflammation or oedema in this brain region.72In addition to midline structures, we observed significant abnormalities within the left prefrontal WM and left parahippocampal WM, but not in any right hemisphere WM structures. This is consistent with several studies in mTBIincreases rather than decreases in FDC  in the acute mTBI group. Decreases in this FD metric can be interpreted as a loss of axons.53 In contrast, increases in FD can be interpreted as an increase in the total intra-axonal volume occupied by fibre structures aligned in a given direction, even in the presence of crossing fibre pathways.53 In the present context, our finding of increased FD is entirely compatible with cytotoxic oedema in these fibre structures. An increase in membrane permeability could result in axonal swelling,73–75 and larger axonal diameters76  decreases] have been observed at the acute, subacute and chronic stages following injury, for up to 6 months.79 The chronic nature of increases in FA has raised questions about its interpretability as cytotoxic oedema,79 particularly if the inflammatory process were to be followed by necrotic cell death.80 Chronically increased FA, however, may be misleading, as the same direction of FA changes in the acute and chronic stages following mTBI could arise from different processes, for example, the loss of crossing fibre structures in the chronic phase of the injury.11DTI studies in which increased FA has been reported have similarly suggested that mTBI is characterized by cytotoxic oedema.decreases in FDC by the subacute stage  recovery following transient inflammation and/or oedema or (ii) cytotoxic oedema followed by neuronal loss due to axotomy. Thus, the trajectory of changes in fixel-based metrics may predict clinical recovery in that individual.In our study, the increases in fixel-based metrics observed in the acute mTBI group did not appear to persist into the subacute stage. Indeed, if anything, our findings suggest there may be subtle te stage , given t78 In the present study, while we hypothesized that FD and cross-sectional increases observed in the acute mTBI group would relate to cognitive abnormalities, we did not find any evidence to support this.There is some evidence from DTI studies to suggest that inflammatory processes in acute mTBI may relate to symptom severity and clinical outcomes.16 Given that our acute mTBI group had a mean time since the injury of 7.5 days  of mTBI, irrespective of time since injury.44 Our present findings suggest that tract-specific abnormalities may normalize after 12 days. However, it is essential to emphasize the highly individualized nature of brain injury, symptoms and recovery. Injured players may exhibit different recovery profiles and require an individualized assessment to guide return-to-play.In our study, the acute period was relatively long (≤12 days). This period was selected to align with current protocols for the AFL footballers (a minimum 12-day break from return-to-play following a concussion).83 loss of crossing fibre populations27 and gliosis.84 This can result in difficulty interpreting the clinical significance of DTI-based findings. In the present study, due to how diffusion MRI data have been acquired, modelled and analysed, we can better interpret changes in FDC , FBA may be valuable in guiding safe return-to-play following injury in the future.While DTI has been applied to detect axonal injury in individuals with moderate to severe TBI,87–91 However, the major advantage of FBA is that it moves entirely beyond a tensor-based model in which comparisons are inherently voxel-averaged, to using a fibre tract-specific model which enables more directly interpretable measures of structural connectivity.36 FBA has now been applied across numerous neurological disorders,38 as well as in recent TBI studies.92–94 Of note, our findings corroborate recent work in a small cohort of Australian Rules footballers that has similarly reported increases in fixel-based metrics in concussed individuals.95It should be noted that there have been various advanced diffusion methods that have been developed over the past decade. Some mTBI studies have implemented such diffusion models including diffusion kurtosis imaging and neurite orientation dispersion and density imaging.While we argue that FBA presents a major technical advantage, there are limitations pertaining to our study cohort. Our findings are based on a relatively small cohort of mTBI participants, and although we had a well-matched sample of control participants, demographic measures that could influence fibre-specific measures (such as years of education) were not available for these participants. Our study included a highly controlled cohort of professional athletes, in whom findings may not be generalizable to other TBI cohorts.72 and there is increasing evidence regarding the deleterious effects of repeat concussions.97 However, in this study, we were unable to account for the number of previous concussions, as this self-reported and often unreliable data were not available for all participants. Despite this, the subacute mTBI cohort used in this study can in many ways be considered an almost ideal control cohort for the acute mTBI participants, given that they were professional athletes likely to be well matched in demographic measures, concussion history, sporting ability and training requirements. The similarities in the affected fibre pathways when comparing the acute and subacute mTBI groups, to when we compared the acute mTBI with the healthy control cohort, provide comfort that these changes relate to acute effects of mTBI, and not to other potential differences between the acute and healthy control participants.Professional AFL players often report numerous concussions during their sporting careers,Finally, while we hypothesize on the potential trajectory of fibre-specific changes over the acute and subacute stages of mTBI, we cannot assess the temporal changes with our cross-sectional data. Given that this study included professional athletes who were recruited by team doctors, their inclusion in the study was potentially driven by concern from the medical professionals who assessed their recovery and was also only possible when athletes did not have substantial training and competition commitments. The acute mTBI group represented a cohort of professional athletes recruited during their mandated rest period. However, participants in the subacute mTBI group (more than 12 days after injury) were likely recruited due to poor recovery or persistent symptomatology. The subtle abnormalities detected in the subacute stage in our cohort may be characteristic to those with poor recovery or persistent symptoms . Future Acute mTBI is characterized by subtle abnormality in select fibre structures. The location and direction of these fibre-specific changes are consistent with previous literature, and our findings support the theory of cytotoxic oedema in the days to weeks following mTBI. However, we did not find evidence to suggest that these fibre tract changes in the first 2 weeks following injury are associated with cognitive deficits nor time since injury. Future work incorporating FBA into longitudinal studies will be critical for further understanding these changes including the time course of these fibre tract changes following sports-related mTBI.fcac208_Supplementary_DataClick here for additional data file.


Science, Acosta-Rodriguez et al. defined a feeding paradigm to maximize the effects of caloric restriction (CR) on lifespans. Aligning feeding with the circadian rhythm and imposing >12-hour fasting daily on caloric-restricted animals can optimally extend lifespans.In a recent issue of While embracing the projection of our life expectancy in the last 100~150 years, we are facing aging, an all-new challenge in human evolution. Aging-associated diseases have gradually replaced communicable diseases, becoming the top cause of death globally. The increasing social and medical burdens call for not only novel therapies for chronic diseases but also early interventions that mitigate the progression of aging and extend life and health spans.1 Animals subjected to CR were demonstrated with ameliorated aging-associated hallmarks, improved metabolism, and better immune functions. Although restricting daily energy intake is the primary goal, classical CR protocols inevitably increase fasting periods and limit food-accessible time. Each of these factors was known to impact body weight and animal health significantly. Thus, disentangling the individual contribution of these parameters within classical CR protocols will facilitate the delineation of mechanisms underlying their beneficial impacts on lifespans. Further exploring the combined effects of different feeding schemes will guide the design of an optimal CR feeding paradigm for extending longevity.Studies involving a wide range of species have illuminated CR as one of the feasible strategies to promote longevity in animals.2 While the total calorie intake is the same for each CR group, the duration of fasting and time of feeding are different  feeding animals as the control.ent Fig. . The CR-Following mice for almost four years, the authors discovered a wide range of lifespan extensions in CR groups Fig. . ConsistTo mechanistically address how CR rescues aging in animals, the authors assessed metabolic markers in young and old mice plasma. As expected, the long-living CR mice maintain high sensitivities to insulin and glucagon-like peptide-1 to mediate glucose homeostasis. Analyzation of liver transcriptomes in young and old mice revealed that 50% of the age-associated genes identified in the AL group restore their expression in every CR group. Further monitoring the transcriptomic changes in the liver every 4 h for 48 h, the authors identified hundreds of cycling genes. With the progression of aging, the amplitude of the circadian rhythmicity of these genes significantly declines. More intriguingly, daytime feeding induced opposite or divergent circadian expression of some cycling genes, whereas night feeding robustly boosts the circadian amplitudes in the old mice. Although the authors did not explicitly explain how feeding paradigms alter mice’s behavior and overall well-being during aging, they did demonstrate that synchronizing the low-energy fasting protocol with circadian rhythm effectively sustains the molecular signatures of the young animals to the old.3, time restriction does not add to the beneficial effect of CR on body weight. However, animal lifespans are extended when CR feeding schemes align with the circadian clock. This implies that the same feeding paradigm may diversely impact different health parameters. We suspect that the effect of feeding regimes on tumor onsets may determine animal lifespans, given that liver cancer is the primary cause of death in Acosta-Rodriguez’s study. As aging stimulates tissue or cell type-specific changes in animals4, different feeding paradigms likely mitigate aging in a tissue or cell type-specific manner. Evaluating the health benefits separately in each organ and considering the effects collectively on animal well-being is critical when selecting feeding paradigms for therapeutic interventions.In conclusion, this study introduced a new feeding paradigm for exploring the collective effects of energy restriction, time-restricted feeding, and circadian intervention on a broad range of animal health. In agreement with a recent clinical trial5 Therefore, analyzing the epigenetic changes in aging mice after different feeding paradigms may provide invaluable insights to elucidate the anti-aging mechanism underlying circadian interventions.This study provided limited clues on how dietary restrictions improve animal lifespans mechanistically. Feeding paradigms can alter circadian oscillation in peripheral organs like the liver in mice and eyes in drosophila. Disrupting peripheral circadian rhythm in some cases is sufficient to reduce longevity. However, it remains unclear how feeding interacts with the circadian rhythm in peripheral organs and how elevated circadian rhythm benefits longevity. A recent study indicates that the dysregulation of core clock protein destabilizes heterochromatin structures and induces cellular senescence in human mesenchymal stem cells in vitro. Exogenously boosting CLOCK expression can enhance cartilage regeneration in aged mice.


Periodontitis is a chronic inflammatory oral disease that affects approximately 42% of adults 30 years of age or older in the United States. In response to microbial dysbiosis within the periodontal pockets surrounding teeth, the host immune system generates an inflammatory environment in which soft tissue and alveolar bone destruction occur. The objective of this study was to identify diagnostic biomarkers and the mechanistic drivers of inflammation in periodontitis to identify drugs that may be repurposed to treat chronic inflammation. A meta-analysis comprised of two independent RNA-seq datasets was performed. RNA-seq analysis, signal pathway impact analysis, protein-protein interaction analysis, and drug target analysis were performed to identify the critical pathways and key players that initiate inflammation in periodontitis as well as to predict potential drug targets. Seventy-eight differentially expressed genes, 10 significantly impacted signaling pathways, and 10 hub proteins in periodontal gingival tissue were identified. The top 10 drugs that may be repurposed for treating periodontitis were then predicted from the gene expression and pathway data. The efficacy of these drugs in treating periodontitis has yet to be investigated. However, this analysis indicates that these drugs may serve as potential therapeutics to treat inflammation in gingival tissue affected by periodontitis. Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola . Th. Thp-valanalysis . An inde2 fold change (log2FC) of −3.78. Fifty-two of the 78 significant DEGs in our current study were immunoglobulin domains, and four DEGs were predicted as transcribed pseudogenes . The remThe Signaling Pathway Impact Analysis (SPIA) algorithm was used to determine whether any known intracellular signaling pathways were enriched in DEGs. This robust approach uses a permutation-based analysis to generate a null distribution for each pathway, which yielded 10 pathways that were significantly affected in periodontitis gingival tissues . SeveralThe next analysis step consisted of determining whether any of the affected signaling pathways contained proteins that are known targets of existing small molecules, monoclonal antibodies, and/or peptides that could be repurposed as potential therapeutics. Using the output from SPIA, 335 proteins in significant pathways were identified that are targets for 500 known drugs . It was An unbiased approach was then applied to identify the drug targets that would be most likely to reverse the observed signaling pathway phenotype. Such a therapeutic approach could reduce or reverse some of the clinical signs and symptoms associated with the disease phenotype. To do so, the protein–protein interaction (PPI) network of drug targets that mapped back to all the statistically significant signaling pathways identified as playing a role in periodontitis gingival tissue were visualized. The initial PPI network, which was constructed using the online STRING database, consisted of 7462 edges and 304 nodes. CytoHubba was then used to reduce this initial network to the top 10 “central hub” proteins based on degrees  . Out of 500 drug candidates identified, 10 drugs that targeted the central hub proteins were identified as top candidates since they would be most likely to reverse the observed periodontitis phenotype . A drug The aim of this study was to identify inflammatory biomarkers and the mechanistic drivers of inflammation, as well as to predict potential therapeutics for various aspects of periodontal disease. For this purpose, two independent RNA-seq datasets were retrieved from NCBI Gene Expression Omnibus (GEO) for RNA-seq meta-analysis. Dataset GSE80715 was previously analyzed in a published study that identified novel gene expression and splicing patterns in periodontitis gingival biopsies , whereasThe signaling pathway impact analysis provided a higher level of analysis of how these differentially expressed genes contribute to the pathogenesis of periodontitis. For instance, the osteoclast differentiation pathway was significantly impacted and activated in periodontal gingival tissue. This is noteworthy since alveolar bone loss is a characteristic of severe periodontitis. Bone-resorbing osteoclasts work in conjunction with bone-forming osteoblasts during bone remodeling through cell–cell interactions and the secretion of signaling proteins  to influence the activation and differentiation of each other ,51. DysrP. gingivalis, are major contributors to microbial dysbiosis and inflammation in periodontitis, inhibiting the LPS-induced activation of TLR4 may be a potential mechanism to reduce inflammation in periodontitis.Using transcriptomics to identify central hubs in protein–protein interaction networks is a novel approach in the field of periodontitis. The best 10 scoring results from this analysis included proteins such as IL-6, toll-like receptor 4 (TLR4), tumor growth factor-beta (TGF-β), and others. IL-6 and IL-1β are pro-inflammatory cytokines that are associated with chronic inflammation, periodontitis, and osteoclast bone resorption ,53,54,55When identifying the top 10 drug targets to treat inflammation in periodontitis, drugs that target hub genes and those drugs which have been FDA-approved were prioritized. Although one prior clinical study has evaluated the post-surgical use of systemic Doxycycline, we are not aware of other studies that have sought to investigate potential therapeutic treatments for periodontal disease. All of the drugs that are reported have been investigated for at least one indication, and some of them are approved for the treatment of chronic inflammatory , autoimmune , and dysregulated bone resorption diseases (Denosumab). Seven of the 10 drug candidates are monoclonal antibodies used to inhibit the signaling pathways of inflammatory cytokines. Satralizumab, Denosumab, and Brodalumab (Siliq) are monoclonal antibodies FDA-approved to treat anti-aquaporin-4 (AQP4) antibody-positive neuromyelitis optica spectrum disorder (NMOSD) ,87, postClazakizumab (NCT03744910), Gevokizumab , Mavrilimumab (NCT01706926), and Gimsilumab (NCT04205851) are monoclonal antibodies that have not been FDA-approved to treat any conditions, but they either have been or are currently being investigated to treat kidney transplant rejection, type I and II diabetes, rheumatoid arthritis, and ankylosing spondylitis, respectively. The three remaining drugs are inhibitors that block cytokine signaling. Interferon beta-1b (Betaseron/Extavia) is a recombinant human interferon that binds to type I interferon receptors (IFNAR1 and IFNAR2) and is FDA-approved as an immunosuppressant to treat relapsing-remitting forms of multiple sclerosis ,101, andThe efficacy of these drugs in treating periodontitis has yet to be investigated. However, this analysis indicates that these drugs may serve as potential therapeutics, either individually or in combination, to treat inflammation in periodontitis gingival tissue. All of these drugs in some way mitigate the inflammatory response or bone resorption via their mechanism of action. As noted above, reducing the inflammation induced by periodontitis may also reduce the severity of other systemic diseases by reducing the number of inflammatory cytokines and activated immune cells that circulate or migrate to other tissues throughout the body. Thus, additional experimentation is justified to further investigate the efficacy of these drugs in reducing the inflammation in the oral cavity of animal models for periodontitis, such as ligature-induced periodontitis in mice.A total of 26 periodontal disease SRA files, which were comprised of 22 periodontitis RNA samples, as well as 22 healthy RNA samples, were downloaded from two series (GSE173082 and GSE80715) retrieved from NCBI Gene Expression Omnibus (GEO). The RNA samples from the GSE80715 series were isolated from nine periodontal-healthy patients , four moderate-periodontitis patients (one patient donating two samples), and three severe-periodontitis patients (two patients donating two samples each for a sum of 10 periodontitis samples). Patient information about the RNA samples from the GSE173082 series was not provided by the investigators on NCBI GEO. Information on the titles of each series, platforms used, library construction, sample type, diagnostic criteria, sample prep, and PubMed ID are provided in p-values (p < 0.05) as calculated by edgeR, together with their fold-change values, were then used as the input for the signaling pathway impact analysis (SPIA) algorithm [All of the Ensembl Gene IDs from edgeR were converted into their corresponding NCBI Gene identifiers utilizing the BioMart database . The NCBlgorithm .The SPIA output file was used as the input for drug target analysis which was performed using the Pathways2Targets R script that had previously been developed . Brieflyhttp://string-db.org/, accessed on 7 March 2022). The PPI network was visualized in the Cytoscape [Drug targets were used to construct the PPI network using the Search Tool for the Retrieval of Interacting Genes (STRING)  databaseytoscape  softwareytoscape , and MCO


Therapists’ forced transition to provide psychotherapy remotely during the COVID-19 pandemic offers a unique opportunity to examine therapists’ views and challenges with teletherapy.We aimed to develop predictive models of three aspects of psychotherapists’ acceptance of teletherapy during the COVID-19 pandemic; attitudes towards teletherapy, concerns about using teletherapy, and intention to use it in the future.N = 795) completed a survey about their experiences during the pandemic, including quality of therapeutic relationship, professional self-doubt, vicarious trauma, and telepsychotherapy acceptance. Regression decision trees machine learning analyses were used to build prediction models for each aspects of telepsychotherapy acceptance.In an international survey, therapists (Attitudes toward telepsychotherapy were most positive for therapists who reported neutral or strong online working alliance, especially if they experienced little professional self-doubt and were younger than 40 years old. Therapists who were most concerned about telepsychotherapy, were those who reported higher levels of professional self-doubt, particularly if they also reported vicarious trauma experiences. Therapists who reported low working alliance were the least likely to use telepsychotherapy in the future.Therapists’ professional self-doubt and the quality of their working alliance with their telepsychotherapy patients appear to be the most pertinent factors associated with therapists’ acceptance of telepsychotherapy during COVID-19, and should be addressed in future training and research.No significant relationships.