RM) helped to understand why certain diseases relapse at the same site after seemingly effective therapy. Therefore, the in-depth characterization of autoreactive T-lyphocytes goes way beyond an academic exercise and opens the door toward improved therapies yielding durable responses. TRM are particularly suitable targets in this regard, and the clinical efficacy of some established and emerging therapeutic strategies such as the inhibition of Janus Kinase 3 or interleukin 15 may rely on their capacity to prevent TRM differentiation and maintenance. Research in this field brings us closer to the ultimate goal in the management of autoimmunity at large, namely resetting the immune system in order to restore the state of tolerance.The presence of one or several autoantigen(s) and a response by the adaptive immune system are the key criteria to classify a pathology as an autoimmune disease. The list of entities fulfilling this criterion is currently growing in the light of recent advancements in the pathogenetic understanding of a number of important dermatoses. The role of autoreactive T-lymphocytes differs amongst these pathologies. While they are directly involved as effector cells attacking and sometimes killing their respective target in some diseases , they provide help to B-lymphocytes, which in turn produce the pathogenic autoreactive antibodies in others (pemphigus and pemphigoid). Atopic dermatits is a chimera in this regard, as there is evidence for both functions. Psoriasis is an example for an entity where autoantigens were finally identified, suggesting that at least a subgroup of patients should be classified as suffering from a true autoimmune rather than autoinflammatory condition. Identification of resident memory T-lymphocytes (T During T-cell development, T-cell receptors (TCR) are generated randomly and subsequently undergo a selection process in the thymus . This inregs), and autoreactive cells that may turn to be harmful and cause autoimmunity. The latter are, however, found at low frequencies in the peripheral T-cell pool, and their functions are hidden by peripheral tolerance mechanisms. Harmful autoreactive T-cells that escape central tolerance are indeed rendered inoffensive via anergy, ignorance, and active suppression by Tregs [reviewed in  blocking antibodies. These compounds represent a promising approach to treat various cancers since they boost specific anti-tumor T-cell immunity by restraining tolerogenic mechanisms exploited by the tumor. The drawback is that peripheral tolerance is weakened and patients may develop so called immune-related adverse events (irAEs). These irAEs differ from “classic” organ-specific autoimmune disease in as much as they affect a broader range of organs and cells . These dregs may become dysfunctional through at least 4 distinct mechanisms, namely plasticity (capacity to produce IL-17 after loss of the transcription factor FOXP3), reduced CD18 expression, epigenetic changes, and inhibitory mRNA targeting FOXP3. This allows proinflammatory cells such as Th1 and TH17 lymphocytes to escape regulation and to perform their effector functions in an uncontrolled manner , their principal mode of action in other diseases is to provide help for B-lymphocytes produce the disease-mediating auto-antibodies . A clinical consequence is that drugs targeting T-cell function are highly effective to treat the former, while B-cell directed drugs currently represent the gold standard for the latter.We will now discuss the current pathophysiological concepts of the clinically most relevant inflammatory skin diseases for which a role of autoreactive T-lymphocytes is either well-established or suggested based on the evidence.Vitiligo  Table 1Table 1 oRM) are candidates representing this memory , and depend on IL-15 for survival once they become resident in the epidermis.Frequently, rapid recurrences at identical locations are observed after stopping therapy , arguings memory , and sevs memory –20. Effopatients . Using aAlopecia areata (AA)  Table 1Table 1 hSimilar to the central nervous system or the placenta, the hair follicule is considered an immune privileged site. Evidence in favor of this hypothesis comes from experiments showing survival of melanocytes in hair follicules grafted from black guinea pig skin onto albino guinea pigs, and viability of human dermal sheath tissues within sex-mismatched transplants , 27. It Several lines of evidence, including elegant experiments using human scalp explants grafted onto severely immunocompromised mice, point toward CD8+ T-lymphocytes as important effector cells. However, maximal induction of the AA phenotype requires the help of CD4+ T-lymphocytes , 30 Usinin silico based on their affinity to the AA-associated allele HLA-A*0201. These were then screened for their capacity to activate CD8+ T-lymphocytes from AA patients. Using this approach, the hair follicle antigens trichohyalin and tyrosinase-related protein-2 were identified as putative autoantigens, with trichohyalin being capable of inducing mononuclear cells to secrete proapoptotic factors harmful to hair follicle keratinocytes  were designed inocytes .Psoriasis  Table 1Table 1 aRM  in psoriasis has been shown   Table 1Table 1 oThe pathophysiology of scleroderma includes three main peculiarities: progressive fibrosis, diffuse fibroproliferative microangiopathy, and inflammation. While the exact etiology remains unknown as of now, environmental as well as genetic factors are considered to be important in the initial phase of the disease. Several lines of evidence suggest that autoreactive T-cells and chronic inflammatory events participate in the initiation or maintenance of the fibrotic process .The first hint comes from genetic and epigenetic studies. Loci in the HLA class II region show the strongest genetic association with the disease, followed by genes involved in B- and T-cell activation and innate immunity. Similarly, epigenetic alterations generally include genes with a role in autoimmunity and T-cell function or regulation .Next, assessment of scleroderma skin revealed that a mononuclear cell infiltrate precedes the fibrotic change and that synthesis of collagen is maximal above it , 57. IntAnother aspect underlying the autoimmune nature of scleroderma is the characteristic presence of anti-nuclear antibodies, including anti-centromere, anti-topoisomerase 1 (anti-topo1) and anti-RNA polymerase III (RNApolIII) antibodies. Anti-topo1 antibodies have high specificity for scleroderma (20–40% of patients) and predict more severe disease and mortality . ConfirmRegarding the presence of autoantibodies, a striking feature is that patients having anti-RNApolIII antibodies but not the other types show a temporal clustering between the onset of cancer and scleroderma. Rosen et al. provided some evidence in favor of a causative link and proposed that somatic mutation of the RNApolIII in the tumor may actually trigger the activation of autoreactive T-cells that cross-react with the tumor mutated antigen, leading to the initiation of the autoimmune scleroderma response .Finally, three randomized controlled trials tested the efficacy of autologous stem cell transplantation for treating scleroderma. A durable improvement in skin fibrosis, pulmonary functions and quality-of-life measures were achieved, suggesting that immune “replacement” and thus deletion of possible autoreactive lymphocytes might be beneficial .While autoreactive T-cells likely represent an integral or causative part of the pathogenesis of scleroderma, the autoantigens and the mechanisms involved remain largely unknown.regs in patient tissues generated contradictory results: most studies reported a reduced frequency while some found an increase in Treg numbers, particularly in early and active disease. Nonetheless, Tregs appear to consistenly harbor a defective suppressing capacity in scleroderma, leading to a weaker peripheral tolerance   Table 1Table 1 din-vitro experiments as well as animal models have established a pivotal role for Fc receptor-mediated effects in the process of blister formation  G and E autoantibodies recognizing BP230 and BP180, both antigens localizing to the hemidesmosomes. While BP230 represents an intracellular component, BP180 is a transmembrane glycoprotein of keratinocytes constituting the basal layer. The collagen type XVII extracellular NC16A domain of BP180 comprises immunodominant B-cell epitopes. Numerous ormation .*0301, a known BP susceptibility allele   is anoth*04:02 transgenic mouse model that T-lymphocytes recognize human desmoglein 3 epitopes in the context of HLA-DRB1*04:02 leading to the induction of pathogenic IgG autoantibodies, which in turn trigger intra-epidermal blister formation   Table 1Table 1 hNumerous cell types contribute to antigen presentation in AD, including dermal dendritic cells, epidermal Langerhans cells, and inflamamtory dendritic epidermal cells expressing a high-affinity receptor for IgE . The latAutoreactivity is a known phenomenon in atopic dermatitis. A systematic review provided evidence that up to a third of patients exhibit autoreactive IgE antibodies . This maregs in atopic dermatitis. The positive correlation of these cells with disease severity both in mouse models as well as in patients  they function either as effector cells or represent the immunological memory in the skin that may be responsible for relapsing disease or (2) they provide help to B-lymphocytes to produce the pathogenic autoantibodies, as is the case of BP and PV. In atopic dermatitis, there is evidence for both roles.To date, targeted therapies such as biologics or small molecules allow to directly and specifically interfere with the central pathomechanisms. These therapies are often more effective when compared with conventional anti-inflammatory therapies, making these agents the key compounds of current treatment algorithms , 90. HowRM are a particularly important subpopulation in the pathophysiology of several autoimmune skin diseases. Their presence elegantly explains recurrance of such diseases after seemingly successful therapy. This makes TRM attractive targets to achieve durable responses. Boniface and Senechal recently pointed out potential strategies in this regard, looking at vitiligo as a model for a skin memory disease  T-lymphocytes may bear a potential . This apregs are potential targets in this regard. These lymphocytes exhibit substantial plasticity. They can lose their immunosuppressive function under the influence of pro-inflammatory cytokines such as IL-23, IL-1β, and IL-2 through the loss of FOXP3, ultimately switching toward a pro-inflammatory function , Kato and Perl showed that IL-21, identified as a key proinflamamtory cytokine in this disease, stimulated both TORC-1 and−2, and abrogated differentiation as well as function of Tregs along with autophagy, a phenomenon underlying Treg dysfunction in SLE  as a central regulator of T-cell lineage specification . Both mTn in SLE . In turnreatment . This apreatment .RM are particularly suitable targets to ensure long-lasting therapeutic effects; the same holds true for the strategies that strengthen the immunosuppressive functions of Tregs. Observations in multiple sclerosis and scleroderma suggest that resetting the immune system in order to restore the state of tolerance as the ultimate goal in the management of autoimmunity at large may be feasible.In summary, it is evident that there are multiple pathways through which autoreactive T-lymphocytes contribute to the pathogenesis of inflammatory skin diseases, some of which have only recently been identified as classical autoimmune disorders. In all of these diseases, targeting the autoreactive T-cell subpopualtion is a promising and in some cases already well-estabilshed therapeutic strategy. TW-HB and NB jointly selected the topic for the review, performed the literature review, wrote the manuscript, and designed the figure along with tables.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Cell membranes with their selective permeability play important functions in the tight control of molecular exchanges between the cytosol and the extracellular environment as the intracellular membranes do within the internal compartments. For this reason the plasma membranes often represent a challenging obstacle to the intracellular delivery of many anti-cancer molecules. The active transport of drugs through such barrier often requires specific carriers able to cross the lipid bilayer. Cell penetrating peptides (CPPs) are generally 5–30 amino acids long which, for their ability to cross cell membranes, are widely used to deliver proteins, plasmid DNA, RNA, oligonucleotides, liposomes and anti-cancer drugs inside the cells. In this review, we describe the several types of CPPs, the chemical modifications to improve their cellular uptake, the different mechanisms to cross cell membranes and their biological properties upon conjugation with specific molecules. Special emphasis has been given to those with promising application in cancer therapy. Cell penetrating peptides (CPPs), formerly defined as protein transduction domains, are a large class of short amino acid sequences (5–30 residues) able to traverse biological membranes and to deliver numerous compounds including small molecules, nucleic acids, proteins, viruses, imaging agents and drugs inside the cells ,2.Drosophila melanogaster was shown to cross the neuronal membrane, to translocate into the nucleus and to cause morphological differentiation of neurons 4-AuNPs in human ovarian adenocarcinoma (SK-OV-3) cells . This peMany diseases such as cancers, or other genetic and nongenetic disorders could be treated by gene therapy ,148. TheA new method associated the concept of intracellular delivery with a transposition of mobile elements such as piggyBac (PB) transposase that is a genetic element that transposes between CPP and plasmid DNA. This method is considered a good option for a potential gene therapy .To improve the low transfection efficiency of TAT CPP bound to DNA, Saleh et al. attached the membrane-active peptide LK15 to TAT (RKKRRQRRRGGGKLLKLLLKLLLKLLK), increasing the gene delivery and enhancing the gene expression in cell lines . Mann etAnother approach to improve the delivery efficiency and the specificity of CPPs—cargo complexes is the conjugation of a CPP to a targeting ligand, for example the TAT-Mu (TM) peptide combined with HER2 antibody mimetic-affibody (AF). This conjugation designated TMAF, allows the specific transgene expression, binds DNA efficiently and protects plasmid DNA from DNase I action .Regarding cancer treatment strategies based on the use of nucleic acids, siRNAs play a significant role but have a poor cellular uptake . It is pA further approach to deliver siRNA has been to use a TAT protein fused to a double-stranded RNA-binding domain (TAT–DRBD) highly specific for siRNAs . The TATMore recently, the new direction of translational research is focused heavily on the use of therapeutic proteins and vaccine peptides in anticancer therapies. The first response to a peptide-based vaccine is a humoral antibody response. The activation of cytotoxic T-cell lymphocytes (CTLs) requires the antigen processing via the MHC class I pathway and CPPs can foster the cytosolic uptake of vaccine-peptides through the MHC I presentation. LAH4, a non-covalently bound cell-penetrating peptide, enhanced the cellular delivery of a tyrosinase-related protein 2 (TRP2) peptide vaccine, inducing anticancer effect in tumor tissues expressing TRP2 in mouse models ,164.Pseudomonas aeruginosa. A minimal protein domain of azurin (amino acids 50 to 67) named p18, contains the cell penetrating properties and enables azurin to enter into human cancer cells. Fragment p28 (amino acids 50 to 77), additionally, can influence p53, can bind and stabilize p53 producing p53-mediated apoptosis and antitumor effects [A novel amphipathic CPP, p28 , is deri effects . This CP effects ,167.Although many clinical trials based on the use of CPP are underway no CPP-based drug has obtained US Food and Drug Administration (FDA) approval as a cancer therapeutic . ClinicaA novel system to control the safety of CPP-mediated intracellular drug delivery is based on the use of a prodrug made up of two components. The first element is an antibody which is a heparin-linked tumor-targeting unit or a magnetic iron oxide nanoparticle (MION) carrier that represents a targeting component. The second element is a drug complex consisting of a covalent polycationic CPPs, such as TAT or LMWP, and a macromolecular drug, such as a protein or a nucleic acid ,171.The drug candidate is a protein toxin or a siRNA which is linked via a degradable S-S bond to nontoxic CPP with low molecular weight such as LMWP. The targeting unit is a MION carrier with a superparamagnetic feature and is covered with a biocompatible heparin-dextran polymer. Together constitute an LMWP-modified drug and the heparin-coated MION as unique pro-drug. The binding between LMWP and heparin of a MION carrier hinders the cell-penetrating function of LMWP during tumor targeting. When the concentration of the MION carriers in the tumor is high, the administration of protamine, a heparin antidote that binds heparin stronger than LMWP, allows the release of LMWP-drug. At the end the drug is removed from LMWP through the degradation of the S-S bond leading to the initiation of tumor death by apoptosis .The mechanism of CPP internalization based on the binding of the peptides to bilayer phospholipids is unspecific and represents a severe obstacle to the clinical use of CPPs. A promising system to increase the specificity is represented by the activatable CPPs (ACPPs) obtained by coupling shielding polyanions to the peptide with target-specific cleavable linkers. Tissue-specific proteases, such as a matrix metatalloprotease 2/9, detach the linker from the inhibitor domain enabling the cleaved ACPP to enter the cancer cells. In 2009, the group of the Nobel Prize winner Prof. Roger Y. Tsien developed the first protease-based ACPP able to cleave the linker between the polycationic CPP and his inhibitor domain enabling the peptide to deliver cargoes specifically in tumor cells [Liu et al. used a legumain-cleavable linker, the alanine-aspargine-alanine (AAN) sequence, which is digested by the legumain protease, an enzyme overexpressed in several solid tumors. Liu used the AAN sequence to branch TAT which was then entrapped into liposomes to deliver Dox into the cells. The addition of AAN-TAT-liposome-Dox to legumain-expressing 4T1 cells showed accumulation and internalization of Dox. Moreover, the treatment of 4T1-orthotopic mice with AAN-TAT-liposome-Dox induced tumor regression .Savariar et al. used the ACPP system as a tumor-detection method. This ACPP was based on the nona-arginine (R9), octa-glutamate (E8), labelled with Cy5 and Cy7, respectively, and the MMP2/9 cleavable linker (PLGCAG). When MMPs in the tumor tissue cleave the linker a fluorescence resonance energy transfer (FRET) between Cy7 and Cy5 were also interrupted producing red fluorescence by Cy5 in the tumor tissue .Tan et al. developed another strategy to target selectivity the cancer cells by fusing an anti-Her-2/neu mimetic peptide to a Tat-derived CPP. The anti-Her-2/neu mimetic peptide recognises the epidermal growth factor ErbB2, which is overexpressed in 30% of breast cancers. The conjugation of the targeting ligand with a CPP improved the efficiency of specific uptake in treated cancer cells ,175.Few CPPs have been used for cancer diagnosis by molecular imaging techniques such as SPECT, PET, optical imaging, and MRI. The sensitivity of such techniques relies on the efficient delivery of contrast agents to the cytoplasm and/or nuclei of the target tissue. Thus, a key strategy to overcome this problem has been the introduction of CPPs in the design of new contrast agents. Nguyen and his collaborators developed a method to see the tumors during surgery based on activatable cell-penetrating peptides (ACPPs), in which CPP is fluorescently labelled and coupled via a cleavable linker to a neutralizing peptide. The presence of proteases specific for tumor tissue allows the cleavage of linker dissociating the inhibitory peptide from CPP that can enter into the cells. Into immunocompetent mice grafted with syngeneic cells derived either from spontaneous tumors in transgenic mice, Cy5-labeled free ACPP and ACPPD (Cy5 and gadolinium–DOTA) allowed to delineate the margin between tumor and adjacent tissue, resulting in a superior precision of tumor resection. Surgery guided by ACPPD enabled preoperative whole-body tumor detection by MRI, intraoperative guidance by real-time fluorescence, intraoperative histological analysis of margin status by fluorescence, and postoperative MRI tumor quantification ..Mitochondria are the powerhouses of cells, and they control several programmed cell death mechanisms. One of the hallmarks of the cancer is the hypoxic condition that is lethal for healthy cells. Under inadequate amounts of oxygen, mitochondria do not produce enough ATP, tumor cells overexpress hypoxia-inducible factor-1 (HIF-1), and the induction of this factor upregulates the glycolytic pathway. Accumulation of Krebs cycle substrates such as succinate occurs. Malignant cells are characterized by decreased expression or mutated p53 which cause the escape from hypoxia-mediated cell death. The mutated tumor suppressor protein causes a down-regulation of mitochondrial respiration an up-regulation of glycolysis. Reactive oxygen species (ROS) are produced during a normal cellular function. Also, a dysfunctional mitochondrial respiratory chain produces an abnormal amount of ROS that are extremely reactive and unstable species. This chemical reactivity induces lipid peroxidation and protein oxidation and degradation. ROS induce damage mitochondrial DNA (mtDNA) in the form of mutations, deletions, gene amplification, and rearrangements. The mitochondria-mediated intrinsic apoptotic pathway is suppressed, and the activation of oncogenes and the inactivation of suppressor genes can occur . These changes are typical of cancer cells ,178.Since mitochondria play this critical role in mediating cell death, could be promising to have anti-cancer drugs targeting the mitochondria. Horton et al.  describeThe discovery of small peptides able to cross cell membranes led to the development of new drug delivery systems. The numerous studies obtained from multiple preclinical and clinical trials have clearly demonstrated the ability of CPPs to increase the therapeutic response in different types of human disease including cancer.In the last decade several CPP-based drugs have been evaluated for their activities in phase I/II clinical trials. The AZX100, a phosphorylated peptide analogue of heat shock protein 20 (HSP20) fused to a Tat peptide derived sequence  has shown to reduce keloids, surgical scarring and fibrotic disorders . The RT001, made of botulinum toxin type A molecule fused to a positively charged lysine-rich central peptidic domain situated between two Tat peptides, for the treatment of lateral canthal lines, crow’s feet, and facial wrinkles (NCT01124565). The KAI-9803, the δ-PKC-selective inhibitor peptide dV1-1 conjugated to Tat peptide, has been found effective to limit tissue damage following myocardial infarction (NCT00093197).Few clinical trials evaluated the efficacy of CPP-based drugs for cancer therapy. The p28, a 28-amino-acid peptide derived from the bacterial protein azurin, has shown to cross the cell membrane and to enter the nucleus where it suppresses p53 degradation causing inhibition of the cell cycle and cancer cell proliferation . The p28Several cancer types are treated with the irinotecan, a prodrug that is converted into its active metabolite SN38 by the action of liver carboxylesterases. The SN38 drug cannot be administered directly due to its high insolubility, then the DTS-108, a water-soluble compound comprising SN38 linked to the highly charged oligopeptide DPV1047 (Vectocell1), has been produced and evaluated in preclinical and clinical studies ,184. TheThe major obstacle to CPP-based therapies has been the limited cell type specificity, given that most CPPs are internalized by all cell types, their poor stability in bloodstream and their low bioavailability in target tissues due poor tissue penetration and/or cellular uptake. Several strategies have been developed to increase CPP specificity to diseased tissues such as the conjugation of CPPs with homing peptides or with other targeting ligands such as RGD peptides, folic acid and hyaluronic acid . These aPharmacokinetics and short blood plasma half-life can be improved by using unnatural amino acids and by coupling CPPs and drugs to macromolecular carriers, such as liposomes or biopolymers. The absence of cell specificity has been addressed by variety of controlled delivery strategies using endogenous or extrinsic stimuli to selectively increase uptake of CCP at the disease site. It should be considered that the conjugation of a CPP with cargo could sometimes generate new epitopes inducing immune responses, while a single CPP did not elicit any immune responses. Further experimental and clinical studies are needed to optimize the use of CPPs for delivery of anticancer drugs.


Repeated formative assessments using key feature questions have been shown to enhance clinical reasoning. Key feature questions augmented by videos presenting clinical vignettes may be more effective than text-based questions, especially in a setting where medical students are free to choose the format they would like to work with. This study investigated learning outcomes related to clinical reasoning in students using video- or text-based key feature questions according to their individual preferences.The aim of this study was to test the hypothesis that repeated exposure to video-based key feature questions enhances clinical reasoning to a greater extent than repeated exposure to text-based key feature questions if students are allowed to choose between those different formats on their own.In this monocentric, prospective, nonrandomized trial, fourth-year medical students attended 12 computer-based case seminars during which they worked on case histories containing key feature questions. Cases were available in a text- and a video-based format. Students chose their preferred presentation format at the beginning of each case seminar. Student performance in key feature questions was assessed in formative entry, exit, and retention exams and was analyzed with regard to preceding exposure to video- or text-based case histories.P=.15) and a significantly higher score in the retention exam . The effect was independent of the video- or text-based presentation format, which was set as default in the respective exams.Of 102 eligible students, 75 provided written consent and complete data at all study exams (response rate=73.5%). A majority of students (n=52) predominantly chose the text-based format. Compared with these, students preferring the video-based format achieved a nonsignificantly higher score in the exit exam (mean 76.2% [SD 12.6] vs 70.0% [SD 19.0]; Despite students’ overall preference for text-based case histories, the learning outcome with regard to clinical reasoning was higher in students with higher exposure to video-based items. Time-on-task is one conceivable explanation for these effects as working with video-based items was more time-consuming. The baseline performance levels of students do not account for the results as the preceding summative exam results were comparable across the 2 groups. Given that a substantial number of students chose a presentation format that was less effective, students might need to be briefed about the beneficial effects of using video-based case histories to be able to make informed choices about their study methods. P<.001). In a further study comparing key feature cases with text-based case histories with video-based ones, these results were confirmed in a postintervention exam  but not in a retention exam 9 months later  ) during which they worked on predefined patient case histories that were aligned to the learning objectives addressed in concurrent curricular teaching sessions. In the first and final weeks of the intervention phase as well as in the retention exam, students took identical formative key feature examinations.This monocentric, prospective, nonrandomized intervention study investigated the impact of letting students choose their preferred learning format on the learning outcome with regard to clinical reasoning. The study consisted of a 3-month intervention phase followed by a nonintervention phase of 4 months. During the intervention phase, students attended 45-min weekly computer-based seminars , and all participants provided written consent.Fourth-year medical students at Göttingen Medical School were informed about the study 4 weeks ahead via email and during the first lecture of term. Students enrolled in all modules in winter term 2015 were eligible for study participation. The study was approved by the local ethics committee  or percentages (n) as appropriate. Significance levels were set to 5%.The primary outcome of this study was the difference in percent scores in the exit and retention exam for students preferring text-based case presentations during the intervention phase compared with those preferring video-based case presentations. Having a total number of 8 ECSs with a free choice, the cutoff for allocation to the video-preference group was set to having chosen the video format at least four times . According to this, 2 groups of students were compared with each other by means of an independent Statistical analysis was performed using IBM SPSS Statistics, version 24.00 (SPSS Inc) and GraphPad Prism, version 5.0 (GraphPad Software Inc).A total of 100 out of 102 eligible students for study inclusion provided written consent. Of these, 25 students missed at least one study-related formative exam, resulting in a total number of 75 students with complete data for analysis (effective response rate=73.5%). According to their most frequent choice, 52 students were allocated to the text-preferring group and 23 to the video-preferring group. There were no statistical differences between both groups regarding age at entry exam, attendance at intervention ECS, and percent score achieved in exams during the previous term, taking into account the number of points scored by a particular student as well as the maximum of available points for that same student in the preceding term see .The proportion of students choosing either format was calculated for each ECS. For text-based ECSs, this proportion ranged from 41.9% (n=31) to 87.7% (n=57), and for video-based ECSs, it ranged from 12.3% (n=9) to 58.1% . In the retention exam, students who had preferred videos during the intervention phase scored significantly higher than students preferring text-based items . For video-based items, these figures were 74.8% (SD 12.7) versus 67.6% (SD 20.0); P=.11). Differences were significant in the retention test (text-based items: 77.0% (SD 18.8) vs 65.8% (SD 21.2); P=.03; video-based items: 73.6% (SD 16.6) vs 61.0% (SD 21.2); P=.01).Exam performance was further analyzed according to the way items were presented in the formative exams. As described above, 14 of the 28 items were displayed as videos whereas the other half were presented in written form. The main effect of preferring videos during the intervention phase persisted, regardless of presentation format in the formative exams see : Mean peThis study yielded 2 principal findings: First, the presentation format preferences of students changed in favor of the less time-consuming written format over the course of the intervention phase. Second, students preferring the video-based format outperformed students preferring text-based items in the retention exam, regardless of the item presentation format.presence of virtual patients. With regard to time, the aforementioned study [Several studies reported that students had a positive attitude toward videos for case presentations and that they preferred video- compared with text-based learning ,15,23,24ed study  concludeAccording to the cognitive load theory , medicalAnother potential explanation for the shift in preferences observed in this study is that working with text-based case histories took less time than working with video-based case histories. In any case, the difference in time-on-task between the 2 preference groups might account for the net finding of superior retention exam performance in students preferring video-based case presentations.The findings of this study confirm previous results regarding a positive effect of test-enhanced learning on clinical reasoning by using key feature questions for case-based learning . Both stThe more favorable learning outcome observed in the video-preference group is in concordance with other studies . NotablyThe importance of context for learning outcome was demonstrated over 40 years ago , and it This study adds to the literature in that it helps curriculum planners, medical teachers, and students make informed choices about the design of instructional material. There is a strong rationale for using video-based case presentations combined with key feature questions for teaching clinical reasoning, but it has to be considered that not all students benefit in the same way and at the same time. About one-third of medical students seem to benefit from video-based case presentations. This might be explained by students having an individual preference for audio-visual learning, although other mechanisms cannot be ruled out and should be addressed in future studies. Giving students the opportunity to choose the presentation format they prefer at each single seminar seems to be a reasonable and feasible approach to avoid disadvantages for anyone and to take advantage of the potential of a more authentic format. Furthermore, this would also add up to the described use of mixed methods by being allowed to learn both text and video-based in the course of a curriculum . In the To the best of our knowledge this is the first prospective study using case-based key feature questions for teaching clinical reasoning, allowing students to select their individual learning material. The formative exit and retention exams contained both text- and video-based items to minimize potential effects of training to any format. The items themselves referred to relevant problems of general medicine, and the response rate was favorable.presence of virtual patients may impact on learning outcome, these aspects should be addressed in future studies. Finally, it was technically not feasible to measure the time individual students spent on every single item. However, it can be assumed that reading was less time consuming than watching the respective video.However, this is a monocentric study with a selected group of students as only fourth-year medical students were allowed to participate. Thus, findings of our study are not generalizable to other student groups and subject areas other than general medicine. Regarding ethical aspects, it was not possible to establish a study design without free choice of format as this study was conducted in the official curriculum and there was no way of knowing whether students randomized to either group would be disadvantaged. Hence, self-selection as a potential bias has to be taken into account when interpreting the findings of this study. Furthermore, we did not collect any quantitative or qualitative data on student experience during ECSs. However, as differences between the 2 presentation formats in terms of time, engagement, context, and the Although about two-thirds of medical students preferred text-based case presentations, those students who self-selected to work on video-based presentations achieved better long-term retention of procedural knowledge as assessed with key feature questions. As clinical reasoning is one of the most complex but important objective in medical education, more research is needed to identify the most effective approach to teaching and learning related skills.


Saliva offers many advantages for point-of-care (PoC) diagnostic applications due to non-invasive, easy, and cost-effective methods of collection. However, the complex matrix with its non-Newtonian behavior and high viscosity poses handling challenges. Several tedious and long pre-analytic steps, incompatible with PoC use, are required to liquefy and homogenize saliva samples before protein analysis can be performed. We apply magnet-beating to reduce hands-on time and to simplify sample preparation. A magnet in a chamber containing the whole saliva is actuated inside a centrifugal microfluidic cartridge by the interplay of centrifugal and magnetic forces. Rigorous mixing, which homogenizes the saliva sample, is then initiated. Consequently, fewer manual steps are required to introduce the whole saliva into the cartridge. After 4 min of magnet-beating, the processed sample can be used for protein analysis. The viscosity of whole saliva has been reduced from 10.4 to 2.3 mPa s. Immunoassay results after magnet-beating for three salivary periodontal markers  showed a linear correlation with a slope of 0.99 when compared to results of reference method treated samples. Conclusively, magnet-beating has been shown to be a suitable method for the pre-analytic processing of whole saliva for fully automated PoC protein analysis.  Saliva is becoming an increasingly popular sample matrix for diagnostic purposes due to its wide range of diagnostic applications including for systemic diseases, oral cancer, cardiac and cardiovascular diseases, periodontal disease , as well as infectious diseases like HIV (human immunodeficiency virus) and many more ,5,6,7,8.The aforementioned features of whole saliva mean that it is crucial to carry out time- and resource-intensive pre-analytic steps before the actual detection and analysis of the target proteins that are of diagnostic significance. The most commonly used method for the pre-analytic preparation of whole saliva includes a freezing step for a time period that may range from a few hours to overnight or even longer. This has been reported to result in a reduction of saliva viscosity . Before One of the most important requirements for a saliva-based PoC or chair-side diagnostic system is the use of the sample matrix directly after collection, in order to circumvent manual pre-analytic processing, reduce hands-on time, test duration, and avoid the use of external equipment ,27. MicrCentrifugal microfluidic systems have some inherent advantages in that they do not require external connections to pumps or tubes, are closed systems, and can be compatible with monolithic manufacturing methods. Implementation of mechanical treatment for sample homogenization on such systems has been introduced and uses glass and/or magnetic beads in a microfluidic chamber to enhance the mechanical treatment ,34 for cIn our work, we present magnet-beating as a method for fully automated in situ pre-analytics of whole saliva in a centrifugal microfluidic platform. Samples are processed at room temperature, directly after collection, for downstream protein analysis. Three protein markers of periodontitis, a major oral disease affecting the tissue that surrounds and supports the teeth, were tested within this scope: matrix metalloproteinases MMP-8, MMP-9, and tissue inhibitor of metalloproteinases TIMP-1. Our method uses only a bar-shaped magnet , actuated through a magnetic field and exerting mechanical forces on whole saliva inside a microfluidic chamber. No external steps or extra devices, apart from the PoC device itself, are necessary and no filter is used. This simplifies the integration and reduces the probability of unspecific binding. Characterization of the method included viscosity and biochemical measurements on the samples after magnet-beating and comparison with the reference method.The saliva samples were collected from eight volunteer donors. All donors provided informed consent and the Ethics Committee of the University of Freiburg had no ethical or legal concerns regarding the data included in this work (request number: 10018/19). The number of samples was chosen in order to demonstrate the microfluidic proof-of-principle at a small scale, which would then allow us to continue further work towards full integration and subsequent clinical study, where more samples will be used. The donors were asked not to eat, drink (except water), smoke, nor chew any chewing gum within one hour prior to sample collection. The mouth was rinsed with water at least twice. The donors were given a simple, non-sterile sample container  to collect the accumulating saliva without active stimulation of the saliva flow. The samples were divided into aliquots for further analysis using: (i) processing with the reference method, (ii) processing with magnet-beating, or (iii) untreated whole saliva. Collected samples were treated according to the reference method . The refThe centrifugal microfluidic disk cartridges were designed using SOLIDWORKS 17  and fabricated by means of thermoforming of thin polycarbonate foils (thickness: 250 µm) as described by Focke et al. . They weThe disks were processed in a laboratory prototype LabDisk Player , developed for processing thermoformed LabDisks with a precise motor and temperature control. Magnet-beating was conducted by rotating the disk at 15 Hz for 4 min below four permanent magnets mounted beneath the lid of the processing device  Figure . Upon co−1 for the shear rate. The viscosity of whole saliva and water, as a reference, was measured with the rheometer Physica MCR101  using a conical plate CP25-1 applying a ramp from 50 to 3000 sTo determine the total protein concentration of whole saliva, the Pierce BCA assay  was used, while the protocol of the assay was optimized for the read-out with a volume of 2 µL on the NanoDrop One . The samples were diluted twice with double-distilled water. The working reagent was mixed together with 50 parts reagent A and one part reagent B. Then, 20 µL working reagent and 5 µL standards or sample were mixed and incubated for at least 15 min at 37 °C. The total protein concentration of the sample was calculated with the help of a BSA  standard. Enzyme-linked immunosorbent assay (ELISA) was performed with three salivary periodontal markers, namely MMP-8, MMP-9, and TIMP-1. The ELISA kits were provided by BioVendor (Czech Republic) and were used according to the supplier’s protocols, with sample dilutions as follows: 50-fold for MMP-8, 80-fold for MMP-9, and 250-fold for TIMP-1. The read-out was conducted on a microtiter plate reader . The unknown concentrations of the samples were deduced from the standard curves using 4-parameter logistic fit .−1) and total protein concentration as the output. Rotating frequencies between 5 and 15 Hz, magnet-beating durations between 1 and 4 min, sample volumes between 200 and 400 µL, and the presence  or absence (only the bar-shaped magnet) of beads in the chamber were tested according to the screening design (Design of Experiments (DoE) for optimizing the system was created with Minitab 19  using a screening design with viscosity  the frequency of disk rotation; (ii) the duration of magnet-beating; (iii) the sample volume; and (iv) the inclusion or exclusion of beads in combination with the bar-shaped magnet. The first two are inherent parameters of our processing system (microfluidic disk). The sample volume was included in the DoE because the accurate pipetting of saliva has been found to be challenging in past experiments  due to tAll of the above four input parameters were evaluated with a screening DoE. According to the DoE results, the magnet-beating settings were chosen to be the following: 400 µL sample volume treated at 15 Hz disk rotating frequency for a duration of 4 min and without the use of beads but only the bar-shaped magnet  than the viscosity of the untreated saliva. This is quite a substantial improvement in the fluidity of the matrix as it approached water-like behavior and its applicability in microfluidic systems therefore improved. At high shear rates of 3000 s−1, no significant difference in viscosity was found between the samples treated with the reference method and those which underwent magnet-beating. No difference was found either when they were compared to the untreated whole saliva (though they were still less viscous than the latter). Furthermore, the treatment of saliva (with either of the two methods) was shown to lower the standard deviation of the viscosity measurements at low shear rates.Using the parameters defined by the DoE, the performance of the system was tested with regard to its impact on whole saliva viscosity. We compared the viscosity of three whole saliva samples: (i) treated with magnet-beating; (ii) treated according to the reference method; and (iii) without treatment. Such measurements were crucial in order to assess the impact of our system because whole saliva sample handling challenges are related strongly to viscosity . Shear r changed . As seenOver the entire shear rate range , we obseTotal protein concentration was evaluated using a BCA assay to measure whole saliva samples from four voluntary donors after magnet-beating compared to untreated whole saliva and the reference treatment method. Untreated whole saliva is difficult to pipette  and alth2 of 0.92  was tested by performing ELISA as this is the typical method used for protein marker immunoassays. Samples were collected from eight voluntary donors and separated into two 500 µL aliquots for processing with the reference method of freezing, thawing, and centrifugation, as well as with magnet-beating. ELISA was performed on both aliquots after pre-analytic processing. The ELISA results of magnet-beating showed a clear correlation with the results from the reference method with a slope of 0.99 of the linear fit and an R of 0.92 . This shows that the pre-analytic method of magnet-beating causes no reduction in protein concentration  but also correlates excellently with the reference method. We presume that the ELISA performance on the mechanically-treated whole saliva correlates so well with the ELISA performance on the reference  treated whole saliva due to impact on viscosity itself , 400 µL sample volume in a microfluidic disk rotating at 15 Hz for 4 min. Both the reference method and the magnet-beating method had a similar, positive effect on the viscosity of the whole saliva, a key parameter for efficient handling on a microfluidic system. Furthermore, ELISA results for three major periodontal biomarkers in magnet-beating treated whole saliva samples showed excellent correlation with the results acquired using the reference treatment method. This indicates that the magnet-beating method is suitable as a pre-analytic process for whole saliva. In addition, the treatment duration was reduced from hours (under reference method) to less than 5 min. Consequently, achieving the same fluidic and biochemical impact on whole saliva with the magnet-beating method as with the reference method, and doing so in a much shorter period of time and with a chair-side/PoC-compatible platform, paves the way for the integration of the magnet-beating into a fully-automated sample-to-answer saliva-based biomarker detection workflow, performed with minimal hands-on steps and user intervention at room temperature.


The prevalence of smoking among people living with HIV (PLHIV) is higher than that reported in the general population, and it is a significant risk factor for noncommunicable diseases in this group. Mobile phone interventions to promote healthier behaviors  have the potential to reach a large number of people at a low cost. It has been hypothesized that mHealth interventions may not be as effective as face-to-face strategies in achieving smoking cessation, but there is no systematic evidence to support this, especially among PLHIV.This study aimed to compare two modes of intervention delivery  for smoking cessation among PLHIV.Literature on randomized controlled trials (RCTs) investigating effects of mHealth or face-to-face intervention strategies on short-term (4 weeks to <6 months) and long-term (≥6 months) smoking abstinence among PLHIV was sought. We systematically reviewed relevant RCTs and conducted pairwise meta-analyses to estimate relative treatment effects of mHealth and face-to-face interventions using standard care as comparison. Given the absence of head-to-head trials comparing mHealth with face-to-face interventions, we performed adjusted indirect comparison meta-analyses to compare these interventions.A total of 10 studies involving 1772 PLHIV met the inclusion criteria. The average age of the study population was 45 years, and women comprised about 37%. In the short term, mHealth-delivered interventions were significantly more efficacious in increasing smoking cessation than no intervention control  and face-to-face interventions . In the short term, face-to-face interventions were no more effective than no intervention in increasing smoking cessation . In terms of achieving long-term results among PLHIV, there was no significant difference in the rates of smoking cessation between those who received mHealth-delivered interventions, face-to-face interventions, or no intervention. Trial sequential analysis showed that only 15.16% (726/1304) and 5.56%  of the required information sizes were accrued to accept or reject a 25% relative risk reduction for short- and long-term smoking cessation treatment effects. In addition, sequential monitoring boundaries were not crossed, indicating that the cumulative evidence may be unreliable and inconclusive.Compared with face-to-face interventions, mHealth-delivered interventions can better increase smoking cessation rate in the short term. The evidence that mHealth increases smoking cessation rate in the short term is encouraging but not sufficient to allow a definitive conclusion presently. Future research should focus on strategies for sustaining smoking cessation treatment effects among PLHIV in the long term. The introduction of effective antiretroviral therapy has resulted in a marked reduction in AIDS-related mortality worldwide. Patterns of morbidity and mortality have shifted from AIDS-related opportunistic infections to age-related comorbidities; moreover, it is now recognized that people living with HIV (PLHIV) are at increased risk of developing cardiovascular disease ,2. This Tobacco use is the single most common cause of preventable death worldwide and an important modifiable risk factor for several chronic conditions, including coronary heart diseases, chronic obstructive pulmonary diseases, and certain cancers . About 1We conducted searches on the following major databases: Embase, Medical Literature Analysis and Retrieval System Online, the Cochrane Library Central Register of Controlled Trials, the ClinicalTrials.gov registry, and cross-references of relevant articles for randomized controlled trials (RCTs) investigating the effectiveness of smoking cessation interventions among HIV-positive smokers and published until up to May 2018. Types of population (PLHIV); types of intervention and comparator ; types of outcome (smoking abstinence); and study design (RCTs).We evaluated each identified study against the following predetermined selection criteria: Two authors (CUN and MA) screened the titles and abstracts of all the potential studies we identified as a result of the search and coded them as “retrieve”  or as “do not retrieve.” Any disagreements were arbitrated by a third author (OAU). Subsequently, CUN and MA assessed the full-text study reports to confirm their eligibility for inclusion while noting the reasons for excluding studies considered ineligible for the meta-analysis. Again, any disagreements were resolved following discussions with OAU.CUN and MA extracted demographic and clinical data from the included studies where available. Data on trial design, sample size, mean age, proportion of women, average daily number of cigarettes, interventions, outcomes, and follow-up durations were extracted. Any disagreements were resolved following discussions with OAU.The main outcome was short-term smoking abstinence, which has been defined as abstinence of at least 4 weeks duration, but less than 6 months after the intervention was initiated . The secCUN and MA judged the risk of bias in each included study using the Cochrane risk of bias assessment tool, which includes the following domains: randomization sequence generation (selection bias); allocation concealment (selection bias); blinding of participants, providers, (performance bias) and outcome assessors (detection bias); completeness of outcome data (attrition bias); and selective outcome reporting (reporting bias). Each RCT was classified as having “high,” “low,” or “unclear” risk of bias in each domain . OAU resTAB can be calculated by using the following equation:We adopted an adjusted indirect comparison meta-analysis -18, a loT represents the treatment effect  between the 2 interventions. SE is calculated as follows:where I2 statistic; a value greater than 50% implied that the treatment estimates were considerably heterogeneous across the included studies. The pooled treatment estimates were reported using RRs and 95% CIs.All data were analyzed using R package “stats” (version 3.2.2). As part of the primary analysis, subgroup analysis was conducted based on the intensity and duration of follow-up period. Analysis was performed separately for short-term (4 weeks to <6 months) and long-term (≥6 months) smoking abstinence. We also quantified heterogeneity by computing the P<.05) meta-analysis included potentially spurious evidence of effect, that is, the cumulative Z-curve did not cross the monitoring boundaries (curve A), or firm evidence of effect, that is, the cumulative Z-curve crossed the monitoring boundaries (curve B). Nonsignificant (P ≥.05) meta-analysis included absence of evidence, that is, the meta-analysis included less patients than the required information size (curve C), or lack of effect, that is, the meta-analysis included more patients than the required information size (curve D). We conducted TSA using TSA version 0.937 with an intention to maintain an overall 5% risk of a type I error and 20% risk of a type II error (power of 80%).We examined the reliability and conclusiveness of the available evidence using trial sequential analyses (TSA) -21. The The study selection process is illustrated in The 10 included studies comprised a total of 1772 participants, all of whom were current smokers living with HIV. All studies were from a high-income country, that is, the United States . On averAmong the 10 included studies, 6 reported the use of computer-generated lists of random numbers for randomization, whereas the other 4 studies did not describe the random sequence generation process. Allocation concealment was not described in any study; therefore, the risks of selection bias were unclear. Blinding of the participants and investigators was not described in 9 of the 10 studies, leaving 1 study in which investigators facilitated counseling sessions, which was thus judged to have a high risk of performance bias. Outcomes assessors were masked to the intervention in 2 studies, whereas the other 8 studies were assessed to have unclear risks of detection bias. Attrition bias was low in 7 studies, and reporting bias high or unclear in 5 studies .I2) was 6.3%, suggesting that the included studies were not statistically heterogeneous.Our calculations indicated that the optimal information size needed to reliably detect a plausible treatment effect for short-term smoking cessation is 4797 participants . HoweverI2) was 0%, suggesting no evidence that the included studies were statistically heterogeneous.For long-term smoking cessation, that is, abstinence ≥6 months, 3 trials compared face-to-face intervention versus no intervention control group and 2 compared mHealth-delivered interventions versus no intervention control group (n=1546). There was no significant difference in smoking cessation rates between PLHIV randomized to mHealth-delivered interventions and those in the no intervention control group . Similarly, there was no significant difference in smoking cessation rates between face-to-face interventions and no intervention control groups . In addition, adjusted indirect treatment comparison between face-to-face and mHealth interventions revealed no significant difference .In The results suggest that mHealth interventions for smoking cessation in PLHIV leads to better short-term improvement in smoking cessation rates than face-to-face interventions. However, from 6 months after the intervention and onward, there is no evidence of any effect regardless of the mode of intervention delivery. Our findings are broadly consistent with a previous meta-analysis of studies conducted in the general population, which reported a higher pooled smoking abstinence rate associated with SMS text messaging for 3 months compared to SMS text messaging for 6 months . It is iGiven the crucial need for the prevention of cardiovascular disease risk in PLHIV, there is a need for future pragmatic trials comparing mHealth and face-to-face intervention, especially in resource-limited settings that bear the highest burden of HIV and where smoking is now a bigger problem ,34. FurtThe limitations in our study warrant consideration. First, the included studies were conducted in a high-income setting, which potentially limits generalization of the results to low- and middle-income settings in which the burden of HIV and tobacco-related illnesses and deaths are currently most severe . NonetheCompared to face-to-face interventions, mHealth-delivered interventions can boost smoking cessation rates, at least in the short term, among PLHIV with higher smoking prevalence rates than the general population. However, it remains unclear how long the effects of such interventions last. Future research should focus on strategies for sustaining the treatment effect in the long term and move beyond high-income settings.


Avascular necrosis of the femoral capital epiphysis is the most serious complication after traumatic dislocation of the hip in children. This case report discusses the localization and revascularization of the necrotic femoral head following rarely experienced traumatic open anterior hip dislocation in children.Our patient was an 11-year-old Japanese boy who had open anterior hip dislocation sustained in a traffic accident. Reduction of the hip joint was performed in an emergency operation, and he was evaluated using serial gadolinium-enhanced magnetic resonance imaging. T1-weighted magnetic resonance images showed two bands with low signal intensity in the femoral capital epiphysis on coronal and oblique axial planes, indicating the existence of avascular osteonecrosis of the femoral head. We observed gadolinium enhancement in the central region of the epiphysis, where the area between the two bands with low signal intensity was located. Serial assessment with enhanced magnetic resonance images during a non-weight-bearing period of 1.5 years after injury showed revascularization starting from the central region and converging toward the peripheral region. Although the patient had leg-length discrepancy due to the early epiphyseal closure, non-weight-bearing treatment for the avascular osteonecrosis of the femoral head achieved a favorable outcome without any hip joint dysfunction, pain, or sign of secondary osteoarthritic change within 4.5 years after injury.We confirmed the revascularization process of the necrotic lesion in the femoral capital epiphysis in an 11-year-old boy using serial gadolinium-enhanced magnetic resonance imaging. Conservative non-weight-bearing treatment achieved a favorable outcome. Avascular necrosis of the femoral capital epiphysis is the most serious and feared complication after traumatic dislocation of the hip in children; treatment of the severely collapsed femoral head is challenging because it is often unsalvageable –10. Femoet al. [et al. [Herrera-Soto et al.  reportedet al. , 13. Kim [et al. , 15 receOur patient was an 11-year-old Japanese boy who was hit by an automobile while walking. He was admitted to our hospital by a rescue team approximately 30 minutes after injury. Physical examination revealed exposure of the right femoral head from the inside of the thigh  at 1 week after injury, and immediate surgical reduction demonstrated less accumulation on the metaphysis of the injured femoral head than on the contralateral side, suggesting the existence of reduced bone turnover Fig. a. T1-weiConservative non-weight-bearing treatment was applied on the affected right hip using a brace , 23 for Traumatic open anterior dislocation of the hip in children is associated with serious complications and could have a very poor prognosis , 25–29. et al. [et al. [et al. observed revascularization occurring from the periphery to the central region [Bohr et al.  examined [et al.  reportedl region , which iet al. reported that joint loading due to muscle contractions can also contribute to the development of the femoral head deformity, but local non-weight-bearing could provide significantly better preservation of the round shape of the femoral head [Weight-bearing within 6 weeks without accurately assessing either the necrotic area or revascularization might lead to premature breakdown of the hip joint in children with ischemic necrosis after traumatic hip dislocation , 14, 33.ral head . They reGrowth disturbances causing damage to the physis in the peripheral region including the perichondral structures, which play an essential role in the growth of the width and length , result We confirmed the revascularization process of the necrotic lesion in the femoral capital epiphysis after traumatic open anterior dislocation of the hip joint in an 11-year-old boy using serial gadolinium-enhanced MRI. Although he had deformity of the proximal femur with leg-length discrepancy, non-weight-bearing treatment using a brace for 1.5 years achieved a favorable outcome without any hip joint dysfunction, pain, or sign of secondary osteoarthritic change within 4.5 years after injury.


The accuracy and rate of convergence are two important performance factors for initial ground alignment of a strapdown inertial navigation system (SINS). For navigation-grade SINS, gyro biases and accelerometer offsets can be modeled as constant values during the alignment period, and they can be calibrated through two-position ground alignment schemes. In many situations for SINS ground alignment, the azimuth of the vehicle remains nearly constant. This quasi-stationary alignment information can be used as an augmented measurement. In this paper, a piecewise combined Kalman filter utilizing relative azimuth constraint (RATP) is proposed to improve the alignment precision and to reduce the time consumption for error convergence. It is presented that a piecewise time-invariant linear system can be combined into a whole extended time-invariant linear system so that a piecewise combined Kalman filter can be designed for state estimation. A two-position ground alignment algorithm for SINS is designed based on the proposed piecewise combined Kalman filter. Numerical simulations and experimental results show its superiority to the conventional algorithms in terms of accuracy and the rate of convergence. Ground alignment is divided into integrated alignment and self-alignment. The initial-self alignment process generally consists of two stages called coarse alignment and fine alignment ,3,4,5,6.Different schemes can be implemented for single-axis rotation, such as two-position alignment schemes ,25,26,27The north and east velocities are generally used as measurements in the Kalman filter for SINS self-initial alignment ,28. ReceIn many inertial navigation applications, both high initial alignment precision and fast error convergence are required ,16,18. ROn the other hand, for ground self-alignment applications, the SINS is approximately stationary with respect to Earth, and the azimuth remained nearly constant during the quasi-stationary alignment period. The azimuth constraint information could be used as observation, based on which the vehicle velocity, attitude, and IMU errors could be estimated and calibrated. The observation noise related with the IMU azimuth constraint information is generally much smaller under quasi-stationary situations.Using the above considerations, a piecewise combined Kalman filter is proposed in this paper to improve the accuracy and rate of convergence of the two-position alignment based on IMU azimuth constraint information.The rest of the paper is organized as follows. The piecewise combine Kalman filter, the new two-position alignment models and alignment performance by simulation are shown in The concept of the piecewise combined time-invariant linear system model and the piecewise combined Kalman filter is proposed in this section. The conventional two-position alignment model as well as the augmented observation model based on gyro information and vehicle rotation rate constraint are briefly introduced. Finally, an improved two-position alignment scheme is presented based on the piecewise combined Kalman filter, which utilizes IMU azimuth constraint information for self-alignment.The system equation and observation equation of a piecewise time-invariant linear system ,32 can bTherefore, the original piecewise time-invariant linear system model shown in Equation (1) can be rewritten as the following piecewise combined system model:Meanwhile, there are observations associated with two state vectors Consequently, a piecewise combined Kalman filter based on the system dynamic model in Equation (4) and observation model in Equation (5) can be constructed, which is named as PC-KF in the following sections. The PC-KF can be widely used in piecewise constant linear systems for state estimation, while we only focus its application on two-position alignment schemes in this paper.The conventional error state model for SINS rapid self-alignment under quasi-stationary conditions, which is similar to Equation (1), can be written as follows ,18,28: can be designed based on the observation model shown in Equation (10) and the dynamic error model shown in Equation (6). The corresponding conventional two-position initial alignment algorithm is noted as TP in the following sections.As shown in Refs. ,15,16, aIf we ignore small quantities and take the equivalent east gyro error as measurement, then the following equation can be obtained:As can be seen in Equation (14), the augmented observation model can be obtained by adding angular rate measurements. Then, the observation model can be expressed asHere, the corresponding angular rate measurement-augmented two-position initial alignment algorithm is denoted as ARTP. Although sometimes the angular vibration amplitude of the vehicle is very small, the vibration angular rate can be large, especially along horizontal directions. For example, if the vehicle engine is still working in the quasi-stationary situations, In this section, a piecewise combined Kalman filter (noted as PC-KF) is designed for the two-position SINS initial alignment to improve the azimuth accuracy and the rate of convergence.For the two-position initial alignment, we suppose that the SINS is in state A when the IMU is in the first position, and in state B after the IMU has rotated 180° while the two positions have the same time duration .Differently from the conventional SINS alignment system model shown in Equation (6), the combined system model expands to 14 dimensions containing both error states in state A and state B. The system model can be described according to Equation (4):The matrixes The observation model is constructed by taking the north velocity error, the east velocity error, and the relative azimuth error angle as the measurements. The relative azimuth error angle can be obtained based on the IMU azimuth relationship between state A and state B. Suppose the horizontal Euler angles between state A and state B are Taking Hence, the modified observation model is given byConsequently, the piecewise combined Kalman filter (PC-KF) based on the error dynamic model shown in Equation (18) and the modified observation model shown in Equation (26) can be designed. The corresponding two-position initial alignment algorithm with relative azimuth constraints is denoted as RATP in the following sections.According to the system dynamic error model constructed in formance ,26,29. TSimulation analysis is divided into two parts. The first part analyzes the variation of Con.1 represents the stationary condition, Con.2 represents angular vibrations with an amplitude of about 5 arcsec and a random frequency of 5–10 Hz, and Con.3 represents angular vibrations with an amplitude of about 10 arcsec and a random frequency of 5–10 Hz.Practical experimental tests were carried out to compare the two-position alignment performance by using the three schemes described earlier. The total alignment time is 180 s. For the first 90 s, the IMU is in state A, then the IMU rotated The velocity error curves under different conditions are shown in The azimuth errors of the three schemes for 180 s rapid alignment are shown in To improve alignment precision and reduce the time needed for error convergence, this paper proposes a novel piecewise combined Kalman filter for state estimation. A two-position ground alignment algorithm for SINS is designed based on the proposed piecewise combined Kalman filter. Simulation results show that the proposed RATP algorithm presents better performance under different experimental conditions compared with the conventional alignment algorithms. ARTP performs better than TP under stationary condition, and it can achieve a faster convergence rate than TP for rapid alignment, but the accuracy of ARTP accuracy was inferior to TP when the alignment time under angular vibrations was longer. The real experimental results indicate that for the SINS in this paper, the azimuth error of RATP is about 40% less than that of the conventional algorithms under stationary or angular vibration conditions for 180 s rapid alignment. The proposed two-position ground alignment scheme, which is based on a piecewise combined Kalman filter and azimuth constraint information, has important engineering value for rapid SINS self-alignment.


Heart failure (HF) is a major public health concern, prevalent in millions of people worldwide. The most widely-used HF diagnostic method, echocardiography, incurs a decreased diagnostic accuracy for heart failure disease progression when patients are asymptomatic compared to those who are symptomatic. The purpose of this study is to conduct a cost-effectiveness analysis of heart failure diagnosis comparing echocardiography to a novel myocardial strain assessment (Fast-SENC), which utilizes cardiac-tagged magnetic resonance imaging.We develop two models, one from the perspective of payers and one from the perspective of purchasers . The payer model is a cost-effectiveness model composed of a 1-year short-term model and a lifetime horizon model. The hospital/purchaser model is a cost impact model where expected costs are calculated by multiplying cost estimates of each subcomponent by the accompanying probability.The payer model shows lower healthcare costs for Fast-SENC in comparison to ECHO  and a lifetime savings of 37% when utilizing Fast-SENC. Similarly, the hospital model revealed that the total cost per HF patient visit is $184 for ECHO and $209 for Fast-SENC, which results in hospital contribution margins of $81 and $115, respectively.Fast-SENC is associated with higher quality-adjusted life years and lower accumulated expected healthcare costs than echocardiogram patients. Fast-SENC also shows a significant short-term and lifetime cost-savings difference and a higher hospital contribution margin when compared to echocardiography. These results suggest that early discovery of heart failure with methods like Fast-SENC can be cost-effective when followed by the appropriate treatment.The online version of this article (10.1186/s13561-019-0229-7) contains supplementary material, which is available to authorized users. Heart failure (HF) is a major public health concern, with a prevalence of 1–2%, or more than 5.8 million people in the U.S. and over 23 million worldwide –7. The lThere are approximately one million annual hospitalizations in the U.S. due to HF . Heart fEchocardiography, as the most widely-used diagnostic method, measures left ventricular (LV) ejection fraction (EF) as a global index of ventricular systolic function. However, LVEF is affected by the ventricular geometry and loading condition which may remain unchanged in affected patients until the underlying disease process is advanced . MoreoveThere is recent and developing literature describing the clinical utility of myocardial strain assessment using cardiac-tagged magnetic resonance imaging (CMR) in conjunction with algorithms and software to augment the clinical utility of CMR . For exaWe developed models from the perspectives of payers  and from the perspective of purchasers . The payer perspective model is a cost-effectiveness analysis that follows methods recommended by the U.K. National Institute for Clinical Excellence (NICE) as well as guidelines developed by the International Society for Pharmacoeconomics and Outcomes Research (ISPOR).Given insurance switching by patients over time, payers covering initial costs may benefit at all any downstream cost offsets , 24. ConPatient population lifetime costs were modeled with Markov processes. The hypothetical patient cohort is on average 64 years and its characteristics are based on a clinical trial cohort with a pretest probability for early HF of 20%, as determined by a Charlson Comorbidity Index score , 26. TheWe developed the HF model framework based on information obtained from a review of the published literature containing information on the management and clinical outcomes of HF patients. The model assumed patients will undergo the standard HF screening assessing patient history and physical examination. Scoring three or higher on the Charlson Comorbidity Index scale during the initial examination, would add a diagnostic assessment of the heart with either echocardiography (ECHO) or Fast-SENCT to assess the long-term effects of early HF diagnosis with imaging modalities, the model accounted for a lifetime of costs and health effects across a hypothetical cohort of patients using a Markov model of HF disease progression –33. The The long-term expected health effects and costs of imaging modality strategies were calculated by multiplying the total time spent in each disease state by the utilities and costs corresponding to these states, respectively. The model employed 1-year time cycles and the simulation stopped when all patients in the hypothetical cohort died. The simulation begins with a short-term model that divides HF patients based on the imaging modality. The group that got early HF diagnosis with Fast-SENC or went undiagnosed in the ECHO group. With a diagnostic accuracy of 100%, Fast-SENC allowed for patients to be treated with medications and recommended lifestyle modifications, reducing the incident rate of HF hospitalizations . ECHO isThe Markov decision analytic model was structured with five disease states, including the beginning state of HF (Stage B), Stage C, Stage C+, Stage D and the death state as described in the ACCF/AHA Guideline for the Management of Heart Failure Fig.  34]. In. In34]. Fast-SENC is a relatively new technology, therefore clinical data required to populate the model was collected from the HF literature, including health statistics and expert opinions. Data inputs for the payer are shown on Table The model assumed that patients entered into two hypothetical cohorts when they were assessed for HF with either Fast-SENC or ECHO. With the ability to detect changes and deterioration of the heart wall, Fast-SENC was assumed to be able to allow clinicians to start patients with medical therapy and lifestyle changes. Michalsen et al. concluded that 54.2% of HF hospitalization could be avoidable if patients received treatment sooner, adhered to prescribed medications and changed their lifestyles . Thus, wThe model assumed that disease-state costs do not vary across cohorts, and that at each state the following costs were incurred: (1) Stage B costs included annual physician visits, medication and diagnostic imaging; (2) Stage C costs included probability of intervention procedural costs; (3) Stage C+ included costs of HF hospitalization and the probability of rehospitalization; and (4) Stage D costs included palliative care and the likelihood of mechanical assist device implantation. Total disease state costs were multiplied by the appropriate transition probabilities (1 – transition probability) for each corresponding state to calculate the expected cost across cohorts. Finally, we assumed that the quality of life values did not differ among the cohorts. Average utility for all patients in Stage B heart failure was 0.80 for patients with mild HF, 0.65 for advanced HF patient and 0.30 for all patients in the last stages of the HF disease . Health The hospital model is a linear one-year accounting model estimating total cost of Fast-SENC and ECHO imaging ownership, imaging facility and technical costs, test costs, and medication costs. The hospital model aims to provide per patient hospital contribution margin for all HF patients diagnosed early with either ECHO or Fast-SENC. Fast-SENC costs were calculated using an initial purchasing price for the software, an ongoing maintenance cost, and a per-test fee. The hospital model calculated hospital profit contribution margins per HF diagnostic test, comparing Fast-SENC and ECHO. The model quantified lost annual marginal revenue for patients admitted for unplanned hospitalizations and also quantified the additional contribution margins from scheduled interventions. These interventions included valve procedures, ablation, revascularization and cardiac rhythm management , 37, 38.Procedural costs were equivalent to average payer reimbursement rates, which we conservatively estimated to be equivalent to U.S. Medicare rates. Table The results of the payer model are shown in Table The results of the hospital model are presented in Table We performed sensitivity analysis on key input parameters affecting the cost-effectiveness (payer model) of both patient cohorts. These parameters include, for example, Fast-SENC HF diagnostic accuracy, diagnosis of HF post HF hospitalization event for both patient cohorts, reduction in preventable hospitalization in the Fast-SENC group, Fast-SENC test reimbursement and the rate of HF diagnosis post HF hospitalization in the Fast-SENC group. One-way sensitivity analysis resulted in the tornado diagram shown in Fig. In this study, we performed a cost-effectiveness analysis to compare the currently available echocardiography strategy for assessing HF and a newly developed Fast-SENC CMR diagnostic approach. From a payer perspective, we found that Fast-SENC was associated with higher quality-adjusted life years (1.96 v .88) and, over a lifetime, patients in the Fast-SENC cohort accumulated $24,647 per patient in expected healthcare costs compared to the higher costs in the ECHO group . In the first year, Fast-SENC, compared to ECHO, reduced costs by 72%, although the cost-savings difference narrowed to 32% for the lifetime horizon. The driving factor of this apparent decrease in cost savings benefit is the extended lifetime and lower mortality of Fast-SENC arm patients leading to additional costs for care. By increasing the longevity and survival of patients, Fast-SENC’s ability to identify heart failure before patients become symptomatic creates a significant opportunity to monitor and manage patients that otherwise would be identified by a cardiac event. By extrapolating these results to the entire US health system, we estimate the savings potential of Fast-SENC to be over $7 billion annually increasing over time with $19 billion in savings annually by 2030. Actual savings potential could be higher when adjusted for private payer savings.From the hospital perspective, a hospital can  generate $481,600 in contribution margin, which is $238,600 more compared to ECHO. The contribution derives from a combination of a higher profitability per test for Fast-SENC and an increased test volume for monitoring and managing heart failure patients identified by Fast-SENC but missed by ECHO. Fast-SENC’s greater speed and accuracy is believed to impact hospitals and health plans by reducing the frequency of unnecessary procedures and identifying more patients who can benefit the most from more intensive treatment. Fast-SENC’s ability to detect myocardial dysfunction in early heart failure patients can have other beneficial effects for hospitals, including increased ICU bed capacity through reduced HF hospitalizations, decreased 30-day HF patient re-hospitalizations, and better managed HF patients in need of more advanced interventions.There are a few limitations in our study. The first limitation is the complexity of accurately depicting outcomes and resource use by disease state in simulation models. The second limitation pertains to input data, which were in majority retrieved from prospective studies with inherent uncertainties. However, our sensitivity analysis attempted to identify influential factors and thus describe the scenarios in which our results would be valid. A third limitation is the assumption that disease transition probabilities for the Fast-SENC cohort are reduced because of earlier HF diagnosis and earlier treatment. Finally, based on the Michalsen et al. study that found that 54.2% of all hospitalizations are preventable with better patient management and lifestyle, we assume that Fast-SENC-guided diagnosis could capture half of these hospitalizations (27.1%) through improvement in HF detection and management, though it is possible that this assumption is imprecise. Finally, the assumption that the protective effects of earlier treatment are evident in later disease stages could also be considered a model limitation, as there is little literature based on longer-term longitudinal studies to directly support this assumption. Hence, we based this assumption on communications with clinical experts, who advised that the diagnostic effect could reasonably be tied to the treatment effect. The results are likely to be to some degree sensitive to this assumption.Further clinical studies are needed to confirm our model assumptions. However, diagnosing HF earlier in the disease progression and treating patients accordingly is a well-studied area with a number of high-quality published studies that conclude increased patient benefits and reduced mortality, similarly to our study. Despite these limitations, this study suggests that diagnostic tests enabling an early discovery of HF with appropriate treatments can be cost-effective if conditions that influence the economic impact of such tests are well evaluated.Fast-SENC is associated with higher quality-adjusted life years and lower accumulated expected healthcare costs than echocardiogram patients. Fast-SENC also shows a significant short-term and lifetime cost-savings difference and a higher hospital contribution margin when compared to echocardiography. These results suggest that early discovery of heart failure with methods like Fast-SENC can be cost-effective when followed by the appropriate treatment.Additional file 1:Transition Matrix Calculations. (DOCX 15 kb)


Monoclonal antibodies (mAbs) targeting specific proteins are currently the most popular form of immunotherapy used in the treatment of cancer and other non-malignant diseases. Since the first approval of anti-CD20 mAb rituximab in 1997 for the treatment of B-cell malignancies, the market is continuously booming and the clinically used mAbs have undergone a remarkable evolution. Novel molecular targets are constantly emerging and the development of genetic engineering have facilitated the introduction of modified mAbs with improved safety and increased capabilities to activate the effector mechanisms of the immune system. Next to their remarkable success in hematooncology, mAbs have also an already established role in the treatment of solid malignancies. The recent development of mAbs targeting the immune checkpoints has opened new avenues for the use of this form of immunotherapy, also in the immune-rich milieu of the skin. In this review we aim at presenting a comprehensive view of mAbs’ application in the modern treatment of skin cancer. We present the characteristics and efficacy of mAbs currently used in dermatooncology and summarize the recent clinical trials in the field. We discuss the side effects and strategies for their managing. Monoclonal antibodies (mAbs) targeting specific proteins are the most popular form of immunotherapy used in the treatment of cancer and non-malignant diseases. Since the first approval of anti-CD20 mAb rituximab in 1997 for the treatment of B-cell malignancies, the clinically used mAbs have undergone a remarkable evolution. Novel molecular targets are constantly emerging and the development of genetic engineering has facilitated the introduction of mAbs with modified structures. Recent advances in the field of monoclonal antibodies served to improve their safety, decrease immunogenicity and increase capabilities to activate the effector mechanisms of the immune system. Monoclonal antibodies are a booming market currently , Oncovin [vincristine], prednisone (CHOP) chemotherapy (R-CHOP). The treatment of PCDLBCL-LT is extrapolated from diffuse large B-cell lymphoma (DLBCL) due to morphologic, phenotypical and molecular genetic features as well as a clinical behavior they share ,203. HowData on the i.v. use of RTX in indolent CBCL are also case reports (reviewed in ). IntralIn this part we will concentrate on discussing the problems concerning the clinical use of ICIs mainly in the context of melanoma. The application of ICIs encounters the problem of both primary (innate) as well as secondary (acquired) resistance. Three populations of patients—(1) responders, (2) patients with innate and (3) those with acquired resistance—have been identified by analyzing the results of the clinical trials ,208,209.Bifidobacterium species and clinical response to this immunotherapy. In patients treated with ipilimumab specific bacteria genera i.e., Faecalibacterium and Bacteroides [In the case of anti-PD-1 targeting, the incidence of primary resistance has been reported in approximately 40% of untreated patients, 65% of the patients after progression on other therapies and in >70% of those treated with ipilimumab . The priteroides ,216 wereteroides ,217) sugJAK2 mutations resulting in disrupted IFN-γ [The secondary resistance concerns approximately 30% to 40% of patients showing an initial response to anti-PD-1. Although the mechanisms underlying the acquired resistance are not completely deciphered it seems that the upregulation of alternative immune checkpoints i.e., TIM-3 and LAG-3 , JAK2 mued IFN-γ  and decred IFN-γ  play a red IFN-γ ). Based on the finding from a retrospective study comparing the efficacy of ipilimumab monotherapy vs. ipilimumab + nivolumab in patients after progression on PD-1 inhibitors, ipilimumab seems an option for patients with acquired resistance . PreclinThere is an unmet need for biomarkers that will identify patients more likely to respond to ICIs. The advances in the topic have been excellently reviewed in ,225. HerData from clinical trials and cohort studies suggest that PD-L1 expression on tumor cells can be used as a predictor of response ,230,231.In terms of demographic factors it has been shown that although men are highly more susceptible to different types of tumors and have two-times higher risk of mortality from all cancers than women do , their rFeatures of the tumor microenvironment (TME) and the composition of the immune populations in the peripheral blood also associate with the response. Specifically, baseline levels of CD8+ TILs correlate with the likelihood of response. Moreover, the number of CD8+ TILs increases during therapy in responders , suggestBy now, it seems that tumor mutational burden together with T cell-inflamed gene expression profile exhibit the greatest predictive utility in identifying responders and nonresponders to anti PD-1 therapy, as shown in a large study in >300 patient samples with advanced solid tumors and melanoma (representing approx. 30% of the tested samples) from four KEYNOTE clinical trials . Large-sSince immune checkpoints under physiological conditions regulate the immune response to prevent autoimmunity bystander damage of the normal tissue, their inhibition leads to a plethora of immune-related AEs (irAEs). Moreover, exacerbation of already pre-existing conditions ,258 is rFortunately, fatal AEs, with their frequency of between 0.3% and 1.3% are less frequent than in case of other therapeutics . HoweverIn general the irAEs can affect every organ. However, some differences regarding the organ distribution can be identified in the populations of patients treated with anti-CTLA-4 or anti-PD-1/PD-L1. While both these populations suffer from colitis, endocrinopathies and cutaneous toxicity, pneumonitis and nephritis are typical for the group treated with anti-PD-1/PD-L1 . Skin toSome authors suggest that cutaneous immune-related AEs of ICIs i.e., vitiligo and rash may be used as predictors of the clinical response. Indeed, analyses of nivolumab-treated melanoma patients indicate that the incidence of vitiligo and rash correlates with a significant OS improvement ,271. OthBeside strategies combining ICIs with other anti-tumor strategies i.e., conventional chemotherapy (reviewed in ), small-Skin is the human body’s largest organ, and its easy accessibility offers an unprecedented gateway for early detection and diagnosis of diseases. Both, solid and hematological malignancies can arise in skin or secondarily affect it. The incidence of skin cancers has been increasing over the past decades up to 287,000 new cases for melanoma and 1.04 million new cases for non-melanoma in 2018 worldwide. This makes skin cancers a global health burden and a field of intense research contributing to the advancement of treatments in oncology overall. Increased knowledge about signaling and immune pathways led to the development of targeted therapies and immunotherapies representing recent breakthroughs in cancer therapy.These therapies opened the way for personalized and precise treatment strategies, but they also confront physicians with novel adverse drug reactions, with the skin being again among the most commonly affected organs.In light of the above, further research should aim to identify more antibody-targetable molecules, accumulate data on how to predict response to treatment and manage the adverse events. In particular, identifying novel molecular targets that may provide a solution to decreased efficacy of mAbs due to antigen loss as a result of selective pressure is of the utmost importance. While the intracellular molecules represent nearly half of the human proteome and provide an immense reservoir of potential novel targets, they have not yet been extensively explored in oncology . Targeti