N6-methyladenosine (m6A) is the most abundant internal modification of eukaryotic messenger RNA (mRNA) and plays critical roles in RNA biology. The function of this modification is mediated by m6A-selective ‘reader’ proteins of the YTH family, which incorporate m6A-modified mRNAs into pathways of RNA metabolism. Here, we show that the m6A-binding protein YTHDC1 mediates export of methylated mRNA from the nucleus to the cytoplasm in HeLa cells. Knockdown of YTHDC1 results in an extended residence time for nuclear m6A-containing mRNA, with an accumulation of transcripts in the nucleus and accompanying depletion within the cytoplasm. YTHDC1 interacts with the splicing factor and nuclear export adaptor protein SRSF3, and facilitates RNA binding to both SRSF3 and NXF1. This role for YTHDC1 expands the potential utility of chemical modification of mRNA, and supports an emerging paradigm of m6A as a distinct biochemical entity for selective processing and metabolism of mammalian mRNAs.

cFor treating Chagas disease (CD), a current worldwide health problem, only benznidazole and nifurtimox have been approved to be used. In both cases, unwanted drug-related adverse events (ADRs) are frequent when these drugs are used in adults in the chronic stage. The main objective of this study was to establish benznidazole ADRs and their relationship to serum concentrations in patients with chronic Trypanosoma cruzi infection in order to perform more accurate dosages to minimize ADRs. A total of 54 patients were recruited over 12 months. Of these 54 patients, 53 (98%) experienced at least one ADR during follow-up, and the overall average ADR incidence was 2.4 episodes/patient/month. Benznidazole treatment was discontinued in 11 patients, 7 among them due to severe adverse effects. The mean duration of treatment before withdrawal was 11 days. Benznidazole serum concentrations were recorded on days 15, 30, 45, and 60 of follow-up and evaluated according to clinical and epidemiological variables and ADR severity. No relationship was found between the benznidazole serum concentration and the ADRs. The mean (standard deviation) trough serum benznidazole concentrations (all below 20 mcg/ml) on days 15, 30, 45, and 60 were 6.4 (1.9), 6.1 (1.8), 6.2 (2.2), and 5.7 (1.7) g/ml, respectively. Benznidazole serum concentrations do not appear to be related to the appearance of serious ADRs. Further, well-controlled studies are necessary to establish the optimal regimen for benznidazole in adults with chronic CD.

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SUMMARYDuring spinal cord development, the combination of secreted signaling proteins and transcription factors provides information for each neural type differentiation. Studies using embryonic stem cells show that trimethylation of lysine 27 of histone H3 (H3K27me3) contributes to repression of many genes key for neural development. However, it remains unclear how H3K27me3-mediated mechanisms control neurogenesis in developing spinal cord. Here, we demonstrate that H3K27me3 controls dorsal interneuron generation by regulation of BMP activity. Our study indicates that expression of Noggin, a BMP extracellular inhibitor, is repressed by H3K27me3. Moreover, we show that Noggin expression is induced by BMP pathway signaling, generating a negative-feedback regulatory loop. In response to BMP pathway activation, JMJD3 histone demethylase interacts with the Smad1/Smad4 complex to demethylate and activate the Noggin promoter. Together, our data reveal how the BMP signaling pathway restricts its own activity in developing spinal cord by modulating H3K27me3 levels at the Noggin promoter.

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In this animal model of MRSA pneumonia, linezolid showed a better efficacy than vancomycin showed because of a better pharmacokinetics/pharmacodynamics index.

Systemic treatment with linezolid limits endotracheal tube biofilm development and methicillin-resistant Staphylococcus aureus burden. The potential clinical usefulness of linezolid in decreasing the risk of biofilm-related respiratory infections during prolonged tracheal intubation requires further investigation.

SummaryResearch has shown that proteasome inhibitors (e.g., carfilzomib), immunomodulatory agents (e.g., lenalidomide), histone deacetylase inhibitors (e.g., vorinostat) and corticosteroids (e.g., dexamethasone) have synergistic anti-multiple myeloma (MM) activity. This phase I dose-escalation study evaluated a regimen combining carfilzomib, lenalidomide, vorinostat and dexamethasone (QUAD) in patients with relapsed and/or refractory MM. Seventeen patients received carfilzomib (15, 20, or , lenalidomide 25 mg, vorinostat 400 mg, and dexamethasone 40 mg. Common grade ≥3 adverse events included neutropenia (53%), thrombocytopenia (53%) and anaemia (41%). The overall response rate was 53%: 12% of patients achieved a very good partial response (PR) and 41% of patients achieved a PR. At a median follow-up of 10 months, median progression-free survival was 12 months and median overall survival was not reached. Treatment with QUAD was feasible and had encouraging activity in patients with relapsed and/or refractory MM.