Evaluation of bupirimate against rose powdery mildew

Bupirimate 25% Emulsifiable concentrate (EC) was evaluated for efficacy on Sphaerotheca pannosa, the causal agent of rose powdery mildew in vivo. In this experiment Bupirimate 25% EC 6 ml/L and 4 ml/L effectively reduced the powdery mildew infection over rest of the treatments and improved the flower yield. Moreover, application of Bupirimate 25% EC at the doses of 2, 4 and 6 ml/L and even at higher dose 8 ml/L did not show any phyto-toxic symptoms on rose plant. Thus, Bupirimate 25% EC may be considered as compared to other fungicides

Quantitative Proteomic Profiling of Small Molecule Treated Mesenchymal Stem Cells Using Chemical Probes.

The differentiation of human adipose derived stem cells toward a neural phenotype by small molecules has been a vogue topic in the last decade. The characterization of the produced cells has been explored on a broad scale, examining morphological and specific surface protein markers; however, the lack of insight into the expression of functional proteins and their interactive partners is required to further understand the extent of the process. The phenotypic characterization by proteomic profiling allows for a substantial in-depth analysis of the molecular machinery induced and directing the cellular changes through the process. Herein we describe the temporal analysis and quantitative profiling of neural differentiating human adipose-derived stem cells after sub-proteome enrichment using a bisindolylmaleimide chemical probe. The results show that proteins enriched by the Bis-probe were identified reproducibly with 133, 118, 126 and 89 proteins identified at timepoints 0, 1, 6 and 12, respectively. Each temporal timepoint presented several shared and unique proteins relative to neural differentiation and their interactivity. The major protein classes enriched and quantified were enzymes, structural and ribosomal proteins that are integral to differentiation pathways. There were 42 uniquely identified enzymes identified in the cells, many acting as hubs in the networks with several interactions across the network modulating key biological pathways. From the cohort, it was found by gene ontology analysis that 18 enzymes had direct involvement with neurogenic differentiation

Effect of prior treatments on selinexor, bortezomib, and dexamethasone in previously treated multiple myeloma

Therapeutic regimens for previously treated multiple myeloma (MM) may not provide prolonged disease control and are often complicated by significant adverse events, including peripheral neuropathy. In patients with previously treated MM in the Phase 3 BOSTON study, once weekly selinexor, once weekly bortezomib, and 40 mg dexamethasone (XVd) demonstrated a significantly longer median progression-free survival (PFS), higher response rates, deeper responses, a trend to improved survival, and reduced incidence and severity of bortezomib-induced peripheral neuropathy when compared with standard twice weekly bortezomib and 80 mg dexamethasone (Vd). The pre-specified analyses described here evaluated the influence of the number of prior lines of therapy, prior treatment with lenalidomide, prior proteasome inhibitor (PI) therapy, prior immunomodulatory drug therapy, and prior autologous stem cell transplant (ASCT) on the efficacy and safety of XVd compared with Vd. In this 1:1 randomized study, enrolled patients were assigned to receive once weekly oral selinexor (100 mg) with once weekly subcutaneous bortezomib (1.3 mg/m2) and 40 mg per week dexamethasone (XVd) versus standard twice weekly bortezomib and 80 mg per week dexamethasone (Vd). XVd significantly improved PFS, overall response rate, time-to-next-treatment, and showed reduced all grade and grade ≥ 2 peripheral neuropathy compared with Vd regardless of prior treatments, but the benefits of XVd over Vd were more pronounced in patients treated earlier in their disease course who had either received only one prior therapy, had never been treated with a PI, or had prior ASCT. Treatment with XVd improved outcomes as compared to Vd regardless of prior therapies as well as manageable and generally reversible adverse events. XVd was associated with clinical benefit and reduced peripheral neuropathy compared to standard Vd in previously treated MM. These results suggest that the once weekly XVd regimen may be optimally administered to patients earlier in their course of disease, as their first bortezomib-containing regimen, and in those relapsing after ASCT. Trial registration: ClinicalTrials.gov (NCT03110562). Registered 12 April 2017. https://clinicaltrials.gov/ct2/show/NCT03110562

The Trypanosoma cruzi vitamin C dependent peroxidase confers protection against oxidative stress but is not a determinant of virulence.

BACKGROUND: The neglected parasitic infection Chagas disease is rapidly becoming a globalised public health issue due to migration. There are only two anti-parasitic drugs available to treat this disease, benznidazole and nifurtimox. Thus it is important to identify and validate new drug targets in Trypanosoma cruzi, the causative agent. T. cruzi expresses an ER-localised ascorbate-dependent peroxidase (TcAPx). This parasite-specific enzyme has attracted interest from the perspective of targeted chemotherapy. METHODOLOGY/PRINCIPAL FINDINGS: To assess the importance of TcAPx in protecting T. cruzi from oxidative stress and to determine if it is essential for virulence, we generated null mutants by targeted gene disruption. Loss of activity was associated with increased sensitivity to exogenous hydrogen peroxide, but had no effect on susceptibility to the front-line Chagas disease drug benznidazole. This suggests that increased oxidative stress in the ER does not play a significant role in its mechanism of action. Homozygous knockouts could proceed through the entire life-cycle in vitro, although they exhibited a significant decrease in their ability to infect mammalian cells. To investigate virulence, we exploited a highly sensitive bioluminescence imaging system which allows parasites to be monitored in real-time in the chronic stage of murine infections. This showed that depletion of enzyme activity had no effect on T. cruzi replication, dissemination or tissue tropism in vivo. CONCLUSIONS/SIGNIFICANCE: TcAPx is not essential for parasite viability within the mammalian host, does not have a significant role in establishment or maintenance of chronic infections, and should therefore not be considered a priority for drug design

Once-weekly selinexor, bortezomib, and dexamethasone versus twice-weekly bortezomib and dexamethasone in patients with multiple myeloma (BOSTON): a randomised, open-label phase 3 trial

Background Selinexor with dexamethasone has demonstrated activity in patients with heavily pretreated multiple myeloma (MM). In a phase 1b/2 study, the combination of oral selinexor with the proteasome inhibitor (PI) bortezomib, and dexamethasone (SVd) induced high response rates with low rates of peripheral neuropathy, the main dose-limiting toxicity of bortezomib. The aim of this trial was to evaluate the clinical benefit of weekly SVd versus standard bortezomib and dexamethasone (Vd) in patients with previously treated MM. Methods This phase 3, randomised, open label trial was conducted at 123 sites in 21 countries. Patients who were previously treated with one to three lines of therapy, including PIs were randomised (1:1) to selinexor (100 mg once-weekly) plus bortezomib (1·3 mg/m2 once-weekly) and dexamethasone (20 mg twice-weekly) [SVd] or bortezomib (1·3 mg/m2 twice-weekly) and dexamethasone (20 mg 4 times per week) [Vd]. Randomisation was done using interactive response technology and stratified by previous PI therapy, lines of treatment, and MM stage. The primary endpoint was progression-free survival (PFS) in the intention-to-treat population. Patients who received at least one dose of study treatment were included in the safety population. This trial is registered at ClinicalTrials.gov, NCT03110562. Findings Between June 2017 and February 2019, 402 patients were randomised: 195 to SVd and 207 to Vd. Median PFS was 13·93 (95% CI 11·73–NE) with SVd versus 9·46 months (8·11–10·78) with Vd; HR 0·70, [95% CI 0·53–0·93]; P=0.0075. Most frequent grade ≥3 adverse events (SVd vs Vd) were thrombocytopenia (77 [40%] vs 35 [17%]), fatigue (26 [13%] vs 2 [1%]), anaemia (31 [16%] vs 20 [10%]), and pneumonia (22 [11%] vs 22 [11%]). Peripheral neuropathy rates (overall, 32·3% vs 47·1%; OR 0·52, [95% CI 0·35-0·79]; P=0.0010 and grade ≥2, 21·0% vs 34·3%; OR 0·50, [95% CI 0·32-0·79]; P=0.0013) were lower with SVd. There were 47 (24%) deaths on SVd and 62 (30%) on Vd. Interpretation Once-weekly SVd is a novel, effective, and convenient treatment option for patients with MM who have received 1-3 prior therapies. Funding Karyopharm Therapeutics In

Drivers and determinants of strain dynamics following faecal microbiota transplantation

Faecal microbiota transplantation (FMT) is an efficacious therapeutic intervention, but its clinical mode of action and underlying microbiome dynamics remain poorly understood. Here, we analysed the metagenomes associated with 142 FMTs, in a time series-based meta-study across five disease indications. We quantified strain-level dynamics of 1,089 microbial species based on their pangenome, complemented with 47,548 newly constructed metagenome- assembled genomes. Using subsets of procedural-, host- and microbiome-based variables, LASSO-regularised regression models accurately predicted the colonisation and resilience of donor and recipient microbes, as well as turnover of individual species. Linking this to putative ecological mechanisms, we found these sets of variables to be informative of the underlying processes that shape the post-FMT gut microbiome. Recipient factors and complementarity of donor and recipient microbiomes, encompassing entire communities to individual strains, were the main determinants of individual strain population dynamics, and mostly independent of clinical outcomes. Recipient community state and the degree of residual strain depletion provided a neutral baseline for donor strain colonisation success, in addition to inhibitive priority effects between species and conspecific strains, as well as putatively adaptive processes. Our results suggest promising tunable parameters to enhance donor flora colonisation or recipient flora displacement in clinical practice, towards the development of more targeted and personalised therapies

Mitochondrial Redox Metabolism in Trypanosomatids Is Independent of Tryparedoxin Activity

Tryparedoxins (TXNs) are oxidoreductases unique to trypanosomatids (including Leishmania and Trypanosoma parasites) that transfer reducing equivalents from trypanothione, the major thiol in these organisms, to sulfur-dependent peroxidases and other dithiol proteins. The existence of a TXN within the mitochondrion of trypanosomatids, capable of driving crucial redox pathways, is considered a requisite for normal parasite metabolism. Here this concept is shown not to apply to Leishmania. First, removal of the Leishmania infantum mitochondrial TXN (LiTXN2) by gene-targeting, had no significant effect on parasite survival, even in the context of an animal infection. Second, evidence is presented that no other TXN is capable of replacing LiTXN2. In fact, although a candidate substitute for LiTXN2 (LiTXN3) was found in the genome of L. infantum, this was shown in biochemical assays to be poorly reduced by trypanothione and to be unable to reduce sulfur-containing peroxidases. Definitive conclusion that LiTXN3 cannot directly reduce proteins located within inner mitochondrial compartments was provided by analysis of its subcellular localization and membrane topology, which revealed that LiTXN3 is a tail-anchored (TA) mitochondrial outer membrane protein presenting, as characteristic of TA proteins, its N-terminal end (containing the redox-active domain) exposed to the cytosol. This manuscript further proposes the separation of trypanosomatid TXN sequences into two classes and this is supported by phylogenetic analysis: i) class I, encoding active TXNs, and ii) class II, coding for TA proteins unlikely to function as TXNs. Trypanosoma possess only two TXNs, one belonging to class I (which is cytosolic) and the other to class II. Thus, as demonstrated for Leishmania, the mitochondrial redox metabolism in Trypanosoma may also be independent of TXN activity. The major implication of these findings is that mitochondrial functions previously thought to depend on the provision of electrons by a TXN enzyme must proceed differently

Leishmania Mitochondrial Peroxiredoxin Plays a Crucial Peroxidase-Unrelated Role during Infection: Insight into Its Novel Chaperone Activity

Two-cysteine peroxiredoxins are ubiquitous peroxidases that play various functions in cells. In Leishmania and related trypanosomatids, which lack catalase and selenium-glutathione peroxidases, the discovery of this family of enzymes provided the molecular basis for peroxide removal in these organisms. In this report the functional relevance of one of such enzymes, the mitochondrial 2-Cys peroxiredoxin (mTXNPx), was investigated along the Leishmania infantum life cycle. mTXNPx null mutants (mtxnpx−) produced by a gene replacement strategy, while indistinguishable from wild type promastigotes, were found unable to thrive in a murine model of infection. Unexpectedly, however, the avirulent phenotype of mtxnpx− was not due to lack of the peroxidase activity of mTXNPx as these behaved like controls when exposed to oxidants added exogenously or generated by macrophages during phagocytosis ex vivo. In line with this, mtxnpx− were also avirulent when inoculated into murine hosts unable to mount an effective oxidative phagocyte response (B6.p47phox−/− and B6.RAG2−/− IFN-γ−/− mice). Definitive conclusion that the peroxidase activity of mTXNPx is not required for parasite survival in mice was obtained by showing that a peroxidase-inactive version of this protein was competent in rescuing the non-infective phenotype of mtxnpx−. A novel function is thus proposed for mTXNPx, that of a molecular chaperone, which may explain the impaired infectivity of the null mutants. This premise is based on the observation that the enzyme is able to suppress the thermal aggregation of citrate synthase in vitro. Also, mtxnpx− were more sensitive than controls to a temperature shift from 25°C to 37°C, a phenotype reminiscent of organisms lacking specific chaperone genes. Collectively, the findings reported here change the paradigm which regards all trypanosomatid 2-Cys peroxiredoxins as peroxide-eliminating devices. Moreover, they demonstrate, for the first time, that these 2-Cys peroxiredoxins can be determinant for pathogenicity independently of their peroxidase activity

Drivers and determinants of strain dynamics following fecal microbiota transplantation

Fecal microbiota transplantation (FMT) is a therapeutic intervention for inflammatory diseases of the gastrointestinal tract, but its clinical mode of action and subsequent microbiome dynamics remain poorly understood. Here we analyzed metagenomes from 316 FMTs, sampled pre and post intervention, for the treatment of ten different disease indications. We quantified strain-level dynamics of 1,089 microbial species, complemented by 47,548 newly constructed metagenome-assembled genomes. Donor strain colonization and recipient strain resilience were mostly independent of clinical outcomes, but accurately predictable using LASSO-regularized regression models that accounted for host, microbiome and procedural variables. Recipient factors and donor-recipient complementarity, encompassing entire microbial communities to individual strains, were the main determinants of strain population dynamics, providing insights into the underlying processes that shape the post-FMT gut microbiome. Applying an ecology-based framework to our findings indicated parameters that may inform the development of more effective, targeted microbiome therapies in the future, and suggested how patient stratification can be used to enhance donor microbiota colonization or the displacement of recipient microbes in clinical practice