Single-nucleus transcriptomics reveals functional compartmentalization in syncytial skeletal muscle cells.

Syncytial skeletal muscle cells contain hundreds of nuclei in a shared cytoplasm. We investigated nuclear heterogeneity and transcriptional dynamics in the uninjured and regenerating muscle using single-nucleus RNA-sequencing (snRNAseq) of isolated nuclei from muscle fibers. This revealed distinct nuclear subtypes unrelated to fiber type diversity, previously unknown subtypes as well as the expected ones at the neuromuscular and myotendinous junctions. In fibers of the Mdx dystrophy mouse model, distinct subtypes emerged, among them nuclei expressing a repair signature that were also abundant in the muscle of dystrophy patients, and a nuclear population associated with necrotic fibers. Finally, modifications of our approach revealed the compartmentalization in the rare and specialized muscle spindle. Our data identifies nuclear compartments of the myofiber and defines a molecular roadmap for their functional analyses; the data can be freely explored on the MyoExplorer server ( https://shiny.mdc-berlin.de/MyoExplorer/ ).

Which procedures are performed by general internists practicing primary care in Germany? - a cross-sectional study.

BACKGROUND: Due to differences of residency training programs' emphases - inpatient vs office-based - internal medicine and family medicine residents consistently reported differences in preparedness to care for common adult conditions. Study's aim was to add knowledge about procedures that a) are performed by general internists working in primary care and b) should be learned during residency in general internists' appraisal. METHODS: A cross-sectional postal survey was carried out by using a questionnaire that comprised 90 procedures relevant in primary care. Each procedure implied the two questions "Do you perform this procedure in your own practice?" and "How important do you think it is to learn this procedure during residency?" The final questionnaire was sent to 1002 general internists working in primary care in Germany in May 2015. Data analysis was performed using SPSS Version 24.0 (SPSS inc., IBM). Next to descriptive statistics subgroup analyses were performed using cross tabulation and Chi-square tests for evaluation of differences in the performance of most frequently performed procedures in urban or rural areas as well as by male or female physicians. RESULTS: Twenty-eight percent of sent questionnaires (276/1002) could be included in analysis. Mean age of participants was 52 years with 13 years of practice experience; 40% were female. Twenty-nine (32%) of 90 given procedures were performed by at least half of the participants, foremost technical diagnostics, punctures, procedures of the integument and resuscitation. After Bonferroni correction, five of those procedures were performed by more male than female physicians and two procedures by more physicians working in a rural practice than physicians practicing in an urban location. Moreover, 46 (51%) procedures were assessed as important to learn during residency by at least 50% of participants. CONCLUSIONS: General internists working in German primary care perform a narrow scope of procedures offered by primary care physicians. In order to provide best ambulatory care for patients, residency training programs must ensure training in procedures that are necessary for providing high quality care. Therefore, a consensus aligned with patients' and health-systems' needs on procedures required for working as a general internist in primary care is necessary.

[Development of a pharmacological curriculum for general practice: Identifying and prescribing orally administered pharmacological substances with relevance for general practice]. / Entwicklung eines hausärztlich-pharmakologischen Curriculums: Identifizierung und Charakterisierung von hausärztlich relevanten Wirkstoffen mit oraler Applikation.

BACKGROUND: General practitioners (GPs) are among the specialists who prescribe the highest number of medication. Therefore the improvement of pharmacological competencies is an important part of the GP specialist training. The self-concept of general practice stating that GPs are the first contact persons for all health problems makes it challenging to define and acquire competencies for specialist training. While the "Competence-based Curriculum" developed by the German College of General Practitioners and Family Physicians defines diagnoses, reasons for counselling and competencies which are essential for general practice, a similar orientation guide is lacking for the pharmacological field. The aim of this study is to define and characterize pharmacological substances which every GP should know so well that he or she is able to conduct counselling and monitoring. METHODS: We analysed private and public health insurance prescriptions of all general practices participating in the CONTENT project in the period from 2009 to 2014. The analysis was limited to substances with oral application which were prescribed at least once by at least 25 % (n = 11) of the practices. While the 100 most frequent prescriptions were included due to their frequency, less frequently prescribed substances were assessed concerning their relevance for general practice in a rating procedure. The substances included were classified by diagnoses and reasons for counselling. RESULTS: We analysed 1,912,896 prescriptions from 44 practices and 112,535 patients on the basis of the Anatomical Therapeutic Chemical (ATC) classification system. After applying the inclusion criteria, 453 substances were left, 302 of which were considered relevant for general practice and could be assigned to 45 diagnoses / reasons for counselling. CONCLUSIONS: The result of this study could be considered a working draft for a pharmacological curriculum for general practice, which may complement the "Competence-based Curriculum" in the medium term.

Temperament type specific metabolite profiles of the prefrontal cortex and serum in cattle.

In the past decade the number of studies investigating temperament in farm animals has increased greatly because temperament has been shown not only to affect handling but also reproduction, health and economically important production traits. However, molecular pathways underlying temperament and molecular pathways linking temperament to production traits, health and reproduction have yet to be studied in full detail. Here we report the results of metabolite profiling of the prefrontal cortex and serum of cattle with distinct temperament types that were performed to further explore their molecular divergence in the response to the slaughter procedure and to identify new targets for further research of cattle temperament. By performing an untargeted comprehensive metabolite profiling, 627 and 1097 metabolite features comprising 235 and 328 metabolites could be detected in the prefrontal cortex and serum, respectively. In total, 54 prefrontal cortex and 51 serum metabolite features were indicated to have a high relevance in the classification of temperament types by a sparse partial least square discriminant analysis. A clear discrimination between fearful/neophobic-alert, interested-stressed, subdued/uninterested-calm and outgoing/neophilic-alert temperament types could be observed based on the abundance of the identified relevant prefrontal cortex and serum metabolites. Metabolites with high relevance in the classification of temperament types revealed that the main differences between temperament types in the response to the slaughter procedure were related to the abundance of glycerophospholipids, fatty acyls and sterol lipids. Differences in the abundance of metabolites related to C21 steroid metabolism and oxidative stress indicated that the differences in the metabolite profiles of the four extreme temperament types could be the result of a temperament type specific regulation of molecular pathways that are known to be involved in the stress and fear response.

Galectin-1 induced activation of the mitochondrial apoptotic pathway: evidence for a connection between death-receptor and mitochondrial pathways in human Jurkat T lymphocytes.

Galectin-1 (gal-1) triggers T cell death by several distinct intracellular pathways including the activation of the death-receptor pathway. The aim of this study was to investigate whether gal-1 induced activation of the death-receptor pathway in Jurkat T lymphocytes mediates apoptosis via the mitochondrial pathway linked by truncated Bid (tBid). We demonstrate that gal-1 induced proteolytic cleavage of the death agonist Bid, a member of the Bcl-2/Bcl-xL family and a substrate of activated caspase-8, was inhibited by caspase-8 inhibitor II (Z-IETD-FMK). Downstream of Bid, gal-1 stimulated mitochondrial cytochrome c release as well as the activation and proteolytic processing of initiator procaspase-9 were effectively decreased by caspase-8 inhibitor II. Blocking of gal-1 induced cleavage of effector procaspase-3 by caspase-8 inhibitor II as well as by caspase-9 inhibitors I (Z-LEHD-FMK) and III (Ac-LEHD-CMK) indicates that receptor and mitochondrial pathways converged in procaspase-3 activation and contribute to proteolytic processing of effector procaspase-6 and -7. Western blot analyses and immunofluorescence staining revealed that exposure of Jurkat T cells to gal-1 resulted in the cleavage of the DNA-repair enzyme poly (ADP-ribose) polymerase, cytoskeletal alpha-fodrin, and nuclear lamin A as substrates of activated caspases. Our data demonstrate that Bid provides a connection between the death receptor and the mitochondrial pathway of gal-1 induced apoptosis in human Jurkat T lymphocytes.

Investigation of immunological approaches to enhance engraftment in a 1 Gy TBI canine hematopoietic stem cell transplantation model.

OBJECTIVE: Stable mixed hematopoietic chimerism can be established in a canine stem cell transplantation model using a conditioning consisting of total body irradiation (TBI; 2 Gy) and postgrafting immunosuppression with mycophenolate mofetil (MMF) and cyclosporin (CSA). Reduction of TBI had resulted previously in graft rejection in this model. We investigated whether postgrafting stimulation of donor T cells against recipient's hematopoietic antigens or graft augmentation with donor monocyte-derived dendritic cells (MoDC) promote engraftment following 1 Gy TBI. MATERIALS AND METHODS: All dogs received dog leukocyte-antigen-identical bone marrow transplantation. Dogs were conditioned with either 2 Gy TBI (group 1) or 1 Gy TBI, followed by repetitive recipient hematopoietic cell lysate vaccinations (group 2) or graft augmentation with MoDC (group 3). Immunosuppression consisted of CSA and MMF. RESULTS: In group 1, four animals remained stable chimeras for >110 weeks, and three rejected their grafts (week 10, week 14, week 16). All dogs in groups 2 and 3 rejected their graft (median: week 10 and 11, respectively). Peak chimerism and engraftment duration was shorter in the 1-Gy groups (p < 0.05) compared to group 1. CONCLUSION: Neither postgrafting vaccination nor graft augmentation with MoDC were effective in supporting durable engraftment. Additional modifications are necessary to improve potential strategies aimed at establishment of early tissue specific graft-vs-host reactions.

Galectin-1 induced activation of the apoptotic death-receptor pathway in human Jurkat T lymphocytes.

Galectin-1 (gal-1), a member of the family of beta-galactoside binding proteins, participates in several biological processes such as immunomodulation, cell adhesion, regulation of cell growth and apoptosis. The aim of this study was to investigate whether gal-1 interferes with the Fas (Apo-1/CD95)-associated apoptosis cascade in the T-cell lines Jurkat and MOLT-4. Gal-1 and an Apo-1 monoclonal antibody (mAb) induced DNA-fragmentation in Jurkat T-cells whereas MOLT-4 cells were resistant. Gal-1 stimulated DNA-fragmentation could be efficiently inhibited by caspase-8 inhibitor II (Z-IETD-FMK) and a neutralizing Fas mAb. Fas could be identified as a target for gal-1 recognition as demonstrated by immunofluorescence staining, binding of the receptor glycoprotein to immobilized gal-1 and analyses by immunoblotting as well as by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Gal-1 stimulates the activation and proteolytic processing of procaspase-8 and downstream procaspase-3 in Jurkat-T cells. Inhibition of gal-1 induced procaspase-8 activation by a neutralizing Fas mAb strongly suggests that gal-1 recognition of Fas is associated with caspase-8 activation. Our data provide the first experimental evidence for targeting of gal-1 to glycotopes on Fas and the subsequent activation of the apoptotic death-receptor pathway.

Immobilization of enzymes in microtiter plate scale.

Different immobilization methods were adapted to the 96-well microtiter plate scale using esterases as model enzymes. The methods tested were based on adsorption, coprecipitation, aggregation and covalent bonding. The protein covered microcrystals proved to be the best method in terms of yield and expressed activity for the test reaction, which was the alcoholysis of p-nitrophenyl acetate with 1-propanol under anhydrous conditions.