14 research outputs found
Plasmodium falciparum encodes a single cytosolic type I Hsp40 that functionally interacts with Hsp70 and is upregulated by heat shock
Heat shock protein 70 (Hsp70) and heat shock protein 40 (Hsp40) function as molecular chaperones during the folding and trafficking of proteins within most cell types. However, the Hsp70–Hsp40 chaperone partnerships within the malaria parasite, Plasmodium falciparum, have not been elucidated. Only one of the 43 P. falciparum Hsp40s is predicted to be a cytosolic, canonical Hsp40 (termed PfHsp40) capable of interacting with the major cytosolic P. falciparum-encoded Hsp70, PfHsp70. Consistent with this hypothesis, we found that PfHsp40 is upregulated under heat shock conditions in a similar pattern to PfHsp70. In addition, PfHsp70 and PfHsp40 reside mainly in the parasite cytosol, as assessed using indirect immunofluorescence microscopy. Recombinant PfHsp40 stimulated the ATP hydrolytic rates of both PfHsp70 and human Hsp70 similar to other canonical Hsp40s of yeast (Ydj1) and human (Hdj2) origin. In contrast, the Hsp40-stimulated plasmodial and human Hsp70 ATPase activities were differentially inhibited in the presence of pyrimidinone-based small molecule modulators. To further probe the chaperone properties of PfHsp40, protein aggregation suppression assays were conducted. PfHsp40 alone suppressed protein aggregation, and cooperated with PfHsp70 to suppress aggregation. Together, these data represent the first cellular and biochemical evidence for a PfHsp70–PfHsp40 partnership in the malaria parasite, and furthermore that the plasmodial and human Hsp70–Hsp40 chaperones possess unique attributes that are differentially modulated by small molecules
Acute cardiovascular response to resistance training during cardiac rehabilitation: effect of repetition speed and rest periods.
Resistance training has been introduced into rehabilitation to improve the efficiency of the 1980s traditional training. Among the modalities, the choice of recovery period length or repetition speed is hardly explained in term of functional benefit but not in terms of cardiovascular (CV) response. To our knowledge, no investigation has been made on the acute CV effect of repetition speed and rest periods between sets of such training during rehabilitation.Journal ArticleRandomized Controlled TrialSCOPUS: ar.jinfo:eu-repo/semantics/publishe
A map of human genome variation from population-scale sequencing
The 1000 Genomes Project aims to provide a deep characterization of human genome sequence variation as a foundation for investigating the relationship between genotype and phenotype. Here we present results of the pilot phase of the project, designed to develop and compare different strategies for genome-wide sequencing with high-throughput platforms. We undertook three projects: low-coverage whole-genome sequencing of 179 individuals from four populations; high-coverage sequencing of two mother-father-child trios; and exon-targeted sequencing of 697 individuals from seven populations. We describe the location, allele frequency and local haplotype structure of approximately 15 million single nucleotide polymorphisms, 1 million short insertions and deletions, and 20,000 structural variants, most of which were previously undescribed. We show that, because we have catalogued the vast majority of common variation, over 95% of the currently accessible variants found in any individual are present in this data set. On average, each person is found to carry approximately 250 to 300 loss-of-function variants in annotated genes and 50 to 100 variants previously implicated in inherited disorders. We demonstrate how these results can be used to inform association and functional studies. From the two trios, we directly estimate the rate of de novo germline base substitution mutations to be approximately 10−8 per base pair per generation. We explore the data with regard to signatures of natural selection, and identify a marked reduction of genetic variation in the neighbourhood of genes, due to selection at linked sites. These methods and public data will support the next phase of human genetic researc
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Efficacy and safety of sparsentan versus irbesartan in patients with IgA nephropathy (PROTECT): 2-year results from a randomised, active-controlled, phase 3 trial
BackgroundSparsentan, a novel, non-immunosuppressive, single-molecule, dual endothelin angiotensin receptor antagonist, significantly reduced proteinuria versus irbesartan, an angiotensin II receptor blocker, at 36 weeks (primary endpoint) in patients with immunoglobulin A nephropathy in the phase 3 PROTECT trial's previously reported interim analysis. Here, we report kidney function and outcomes over 110 weeks from the double-blind final analysis.MethodsPROTECT, a double-blind, randomised, active-controlled, phase 3 study, was done across 134 clinical practice sites in 18 countries throughout the Americas, Asia, and Europe. Patients aged 18 years or older with biopsy-proven primary IgA nephropathy and proteinuria of at least 1·0 g per day despite maximised renin–angiotensin system inhibition for at least 12 weeks were randomly assigned (1:1) to receive sparsentan (target dose 400 mg oral sparsentan once daily) or irbesartan (target dose 300 mg oral irbesartan once daily) based on a permuted-block randomisation method. The primary endpoint was proteinuria change between treatment groups at 36 weeks. Secondary endpoints included rate of change (slope) of the estimated glomerular filtration rate (eGFR), changes in proteinuria, a composite of kidney failure (confirmed 40% eGFR reduction, end-stage kidney disease, or all-cause mortality), and safety and tolerability up to 110 weeks from randomisation. Secondary efficacy outcomes were assessed in the full analysis set and safety was assessed in the safety set, both of which were defined as all patients who were randomly assigned and received at least one dose of randomly assigned study drug. This trial is registered with ClinicalTrials.gov, NCT03762850.FindingsBetween Dec 20, 2018, and May 26, 2021, 203 patients were randomly assigned to the sparsentan group and 203 to the irbesartan group. One patient from each group did not receive the study drug and was excluded from the efficacy and safety analyses (282 [70%] of 404 included patients were male and 272 [67%] were White) . Patients in the sparsentan group had a slower rate of eGFR decline than those in the irbesartan group. eGFR chronic 2-year slope (weeks 6–110) was −2·7 mL/min per 1·73 m2 per year versus −3·8 mL/min per 1·73 m2 per year (difference 1·1 mL/min per 1·73 m2 per year, 95% CI 0·1 to 2·1; p=0·037); total 2-year slope (day 1–week 110) was −2·9 mL/min per 1·73 m2 per year versus −3·9 mL/min per 1·73 m2 per year (difference 1·0 mL/min per 1·73 m2 per year, 95% CI −0·03 to 1·94; p=0·058). The significant reduction in proteinuria at 36 weeks with sparsentan was maintained throughout the study period; at 110 weeks, proteinuria, as determined by the change from baseline in urine protein-to-creatinine ratio, was 40% lower in the sparsentan group than in the irbesartan group (−42·8%, 95% CI −49·8 to −35·0, with sparsentan versus −4·4%, −15·8 to 8·7, with irbesartan; geometric least-squares mean ratio 0·60, 95% CI 0·50 to 0·72). The composite kidney failure endpoint was reached by 18 (9%) of 202 patients in the sparsentan group versus 26 (13%) of 202 patients in the irbesartan group (relative risk 0·7, 95% CI 0·4 to 1·2). Treatment-emergent adverse events were well balanced between sparsentan and irbesartan, with no new safety signals.InterpretationOver 110 weeks, treatment with sparsentan versus maximally titrated irbesartan in patients with IgA nephropathy resulted in significant reductions in proteinuria and preservation of kidney function