Research resource: the dynamic transcriptional profile of sertoli cells during the progression of spermatogenesis.

Sertoli cells (SCs), the only somatic cells within seminiferous tubules, associate intimately with developing germ cells. They not only provide physical and nutritional support but also secrete factors essential to the complex developmental processes of germ cell proliferation and differentiation. The SC transcriptome must therefore adapt rapidly during the different stages of spermatogenesis. We report comprehensive genome-wide expression profiles of pure populations of SCs isolated at 5 distinct stages of the first wave of mouse spermatogenesis, using RNA sequencing technology. We were able to reconstruct about 13 901 high-confidence, nonredundant coding and noncoding transcripts, characterized by complex alternative splicing patterns with more than 45% comprising novel isoforms of known genes. Interestingly, roughly one-fifth (2939) of these genes exhibited a dynamic expression profile reflecting the evolving role of SCs during the progression of spermatogenesis, with stage-specific expression of genes involved in biological processes such as cell cycle regulation, metabolism and energy production, retinoic acid synthesis, and blood-testis barrier biogenesis. Finally, regulatory network analysis identified the transcription factors endothelial PAS domain-containing protein 1 (EPAS1/Hif2α), aryl hydrocarbon receptor nuclear translocator (ARNT/Hif1β), and signal transducer and activator of transcription 1 (STAT1) as potential master regulators driving the SC transcriptional program. Our results highlight the plastic transcriptional landscape of SCs during the progression of spermatogenesis and provide valuable resources to better understand SC function and spermatogenesis and its related disorders, such as male infertility.

Chromosome 7 gain and DNA hypermethylation at the HOXA10 locus are associated with expression of a stem cell related HOX-signature in glioblastoma.

BACKGROUND: HOX genes are a family of developmental genes that are expressed neither in the developing forebrain nor in the normal brain. Aberrant expression of a HOX-gene dominated stem-cell signature in glioblastoma has been linked with increased resistance to chemo-radiotherapy and sustained proliferation of glioma initiating cells. Here we describe the epigenetic and genetic alterations and their interactions associated with the expression of this signature in glioblastoma. RESULTS: We observe prominent hypermethylation of the HOXA locus 7p15.2 in glioblastoma in contrast to non-tumoral brain. Hypermethylation is associated with a gain of chromosome 7, a hallmark of glioblastoma, and may compensate for tumor-driven enhanced gene dosage as a rescue mechanism by preventing undue gene expression. We identify the CpG island of the HOXA10 alternative promoter that appears to escape hypermethylation in the HOX-high glioblastoma. An additive effect of gene copy gain at 7p15.2 and DNA methylation at key regulatory CpGs in HOXA10 is significantly associated with HOX-signature expression. Additionally, we show concordance between methylation status and presence of active or inactive chromatin marks in glioblastoma-derived spheres that are HOX-high or HOX-low, respectively. CONCLUSIONS: Based on these findings, we propose co-evolution and interaction between gene copy gain, associated with a gain of chromosome 7, and additional epigenetic alterations as key mechanisms triggering a coordinated, but inappropriate, HOX transcriptional program in glioblastoma.

Safety profile of prasugrel and clopidogrel in patients with acute coronary syndromes in Switzerland.

OBJECTIVE: To assess safety up to 1 year of follow-up associated with prasugrel and clopidogrel use in a prospective cohort of patients with acute coronary syndromes (ACS). METHODS: Between 2009 and 2012, 2286 patients invasively managed for ACS were enrolled in the multicentre Swiss ACS Bleeding Cohort, among whom 2148 patients received either prasugrel or clopidogrel according to current guidelines. Patients with ST-elevation myocardial infarction (STEMI) preferentially received prasugrel, while those with non-STEMI, a history of stroke or transient ischaemic attack, age ≥75 years, or weight <60 kg received clopidogrel or reduced dose of prasugrel to comply with the prasugrel label. RESULTS: After adjustment using propensity scores, the primary end point of clinically relevant bleeding events (defined as the composite of Bleeding Academic Research Consortium, BARC, type 3, 4 or 5 bleeding) at 1 year, occurred at a similar rate in both patient groups (prasugrel/clopidogrel: 3.8%/5.5%). Stratified analyses in subgroups including patients with STEMI yielded a similar safety profile. After adjusting for baseline variables, no relevant differences in major adverse cardiovascular and cerebrovascular events were observed at 1 year (prasugrel/clopidogrel: cardiac death 2.6%/4.2%, myocardial infarction 2.7%/3.8%, revascularisation 5.9%/6.7%, stroke 1.0%/1.6%). Of note, this study was not designed to compare efficacy between prasugrel and clopidogrel. CONCLUSIONS: In this large prospective ACS cohort, patients treated with prasugrel according to current guidelines (ie, in patients without cerebrovascular disease, old age or underweight) had a similar safety profile compared with patients treated with clopidogrel. CLINICAL TRIAL REGISTRATION NUMBER: SPUM-ACS: NCT01000701; COMFORTABLE AMI: NCT00962416.

Vitamin D time profile based on the contribution of non-genetic and genetic factors in HIV-infected individuals of European ancestry.

BACKGROUND: Vitamin D deficiency is prevalent in HIV-infected individuals and vitamin D supplementation is proposed according to standard care. This study aimed at characterizing the kinetics of 25(OH)D in a cohort of HIV-infected individuals of European ancestry to better define the influence of genetic and non-genetic factors on 25(OH)D levels. These data were used for the optimization of vitamin D supplementation in order to reach therapeutic targets. METHODS: 1,397 25(OH)D plasma levels and relevant clinical information were collected in 664 participants during medical routine follow-up visits. They were genotyped for 7 SNPs in 4 genes known to be associated with 25(OH)D levels. 25(OH)D concentrations were analysed using a population pharmacokinetic approach. The percentage of individuals with 25(OH)D concentrations within the recommended range of 20-40 ng/ml during 12 months of follow-up and several dosage regimens were evaluated by simulation. RESULTS: A one-compartment model with linear absorption and elimination was used to describe 25(OH)D pharmacokinetics, while integrating endogenous baseline plasma concentrations. Covariate analyses confirmed the effect of seasonality, body mass index, smoking habits, the analytical method, darunavir/ritonavir and the genetic variant in GC (rs2282679) on 25(OH)D concentrations. 11% of the inter-individual variability in 25(OH)D levels was explained by seasonality and other non-genetic covariates, and 1% by genetics. The optimal supplementation for severe vitamin D deficient patients was 300,000 IU two times per year. CONCLUSIONS: This analysis allowed identifying factors associated with 25(OH)D plasma levels in HIV-infected individuals. Improvement of dosage regimen and timing of vitamin D supplementation is proposed based on those results.

Primary care in Switzerland: evolution of physicians' profile and activities in twenty years (1993-2012).

BACKGROUND: According to the Organization for Economic Cooperation and Development, the Swiss healthcare system is one of the most effective in the world. Yet, as other occidental countries, it has to face the increase of chronic diseases frequency and its resulting cost, particularly for primary care (PC). However very few consistent data are available to describe PC features and its evolution over time. The aim of this study is to describe the evolution of the Swiss PC physicians' (PCPs) profile and activities between 1993 and 2012. METHODS: The date come from two independent European surveys carried out in Switzerland respectively in 1993 and 2012. Both surveys were cross-sectional ones and based on representative samples of 200 PCPs, interviewed by questionnaire. RESULTS: In 20 years, PCPs became older (median age 46 vs 56, p < 0.001) and more feminized (7 % vs 22 %, p < 0.001). Nowadays, they more often work in group practices (28 % vs 52 % in 2012, p < 0.001) and are more involved in other paid activities (28 % vs 66 % in 2012, p < 0.001). All the PCPs have a computer in 2012 (78 % in 1993, p < 0.001) and it is mostly used for keeping records of consultations (47 %). The number of daily face-to-face contacts with patients decreased from 31 to 24 but the average length rose from 15 to 20 min (p < 0.001). PCPs provide fewer pediatric and gynecological services but their activity remains globally unchanged in other domains. The frequency of meetings with other disciplines decreased significantly (e.g. once/month face-to-face meets with ambulatory specialists: 78 % vs 23 % in 2012, p < 0.001). The involvement of PCPs in follow-up and treatment of chronic disease globally little differed. In 2012, 8.5 % of the PCPs never performed any chirurgical acts (vs 0 % in 1993, p < 0.001). CONCLUSION: This study showed a substantial evolution of Swiss PC over the last twenty years in terms of socio-demographic, organizational and service provided. The main changes include: feminization and ageing, lower diversity in services provided, fewer but longer consultations. These changes may have important implications for patients' management and will need to be considered for health planning purposes.

Travellers' profile, travel patterns and vaccine practices-a 10-year prospective study in a Swiss Travel Clinic.

BACKGROUND: The travel clinic in Lausanne serves a catchment area of 700 000 of inhabitants and provides pre- and post-travel consultations. This study describes the profile of attendees before departure, their travel patterns and the travel clinic practices in terms of vaccination over time. METHODS: We included all pre-travel first consultation data recorded between November 2002 and December 2012 by a custom-made program DIAMM/G. We analysed client profiles, travel characteristics and vaccinations prescribed over time. RESULTS: Sixty-five thousand and forty-six client-trips were recorded. Fifty-one percent clients were female. Mean age was 32 years. In total, 0.1% were aged <1 year and 0.2% ≥80 years. Forty-six percent of travellers had pre-existing medical conditions. Forty-six percent were travelling to Africa, 35% to Asia, 20% to Latin America and 1% (each) to Oceania and Europe; 19% visited more than one country. India was the most common destination (9.6% of travellers) followed by Thailand (8.6%) and Kenya (6.4%). Seventy-three percent of travellers were planning to travel for ≤ 4 weeks. The main reasons for travel were tourism (75%) and visiting friends and relatives (18%). Sixteen percent were backpackers. Pre-travel advice were sought a median of 29 days before departure. Ninety-nine percent received vaccine(s). The most frequently administered vaccines were hepatitis A (53%), tetanus-diphtheria (46%), yellow fever (39%), poliomyelitis (38%) and typhoid fever (30%). CONCLUSIONS: The profile of travel clinic attendees was younger than the general Swiss population. A significant proportion of travellers received vaccinations that are recommended in the routine national programme. These findings highlight the important role of travel clinics to (i) take care of an age group that has little contact with general practitioners and (ii) update vaccination status. The most commonly prescribed travel-related vaccines were for hepatitis A and yellow fever. The question remains to know whether clients do attend travel clinics because of compulsory vaccinations or because of real travel health concern or both.