230 research outputs found
ProkSeq for complete analysis of RNA-Seq data from prokaryotes
Since its introduction, RNA-Seq technology has been used extensively in studies of pathogenic bacteria to identify and quantify differences in gene expression across multiple samples from bacteria exposed to different conditions. With some exceptions, tools for studying gene expression, determination of differential gene expression, downstream pathway analysis and normalization of data collected in extreme biological conditions is still lacking. Here, we describe ProkSeq, a user-friendly, fully automated RNA-Seq data analysis pipeline designed for prokaryotes. ProkSeq provides a wide variety of options for analysing differential expression, normalizing expression data and visualizing data and results
PopulusPtERF85 Balances Xylem Cell Expansion and Secondary Cell Wall Formation in Hybrid Aspen
Secondary growth relies on precise and specialized transcriptional networks that determine cell division, differentiation, and maturation of xylem cells. We identified a novel role for the ethylene-induced Populus Ethylene Response Factor PtERF85 (Potri.015G023200) in balancing xylem cell expansion and secondary cell wall (SCW) formation in hybrid aspen (Populus tremula x tremuloides). Expression of PtERF85 is high in phloem and cambium cells and during the expansion of xylem cells, while it is low in maturing xylem tissue. Extending PtERF85 expression into SCW forming zones of woody tissues through ectopic expression reduced wood density and SCW thickness of xylem fibers but increased fiber diameter. Xylem transcriptomes from the transgenic trees revealed transcriptional induction of genes involved in cell expansion, translation, and growth. The expression of genes associated with plant vascular development and the biosynthesis of SCW chemical components such as xylan and lignin, was down-regulated in the transgenic trees. Our results suggest that PtERF85 activates genes related to xylem cell expansion, while preventing transcriptional activation of genes related to SCW formation. The importance of precise spatial expression of PtERF85 during wood development together with the observed phenotypes in response to ectopic PtERF85 expression suggests that PtERF85 contributes to the transition of fiber cells from elongation to secondary cell wall deposition
PopulusPtERF85 Balances Xylem Cell Expansion and Secondary Cell Wall Formation in Hybrid Aspen
Secondary growth relies on precise and specialized transcriptional networks that determine cell division, differentiation, and maturation of xylem cells. We identified a novel role for the ethylene-induced Populus Ethylene Response Factor PtERF85 (Potri.015G023200) in balancing xylem cell expansion and secondary cell wall (SCW) formation in hybrid aspen (Populus tremula x tremuloides). Expression of PtERF85 is high in phloem and cambium cells and during the expansion of xylem cells, while it is low in maturing xylem tissue. Extending PtERF85 expression into SCW forming zones of woody tissues through ectopic expression reduced wood density and SCW thickness of xylem fibers but increased fiber diameter. Xylem transcriptomes from the transgenic trees revealed transcriptional induction of genes involved in cell expansion, translation, and growth. The expression of genes associated with plant vascular development and the biosynthesis of SCW chemical components such as xylan and lignin, was down-regulated in the transgenic trees. Our results suggest that PtERF85 activates genes related to xylem cell expansion, while preventing transcriptional activation of genes related to SCW formation. The importance of precise spatial expression of PtERF85 during wood development together with the observed phenotypes in response to ectopic PtERF85 expression suggests that PtERF85 contributes to the transition of fiber cells from elongation to secondary cell wall deposition
The Social context of motorcycle riding and the key determinants influencing rider behavior: A qualitative investigation
Objective: Given the increasing popularity of motorcycle riding and heightened risk of injury or death associated with being a rider, this study explored rider behaviour as a determinant of rider safety and, in particular, key beliefs and motivations which influence such behaviour. To enhance the effectiveness of future education and training interventions, it is important to understand ridersâ own views about what influences how they ride. Specifically, this study sought to identify key determinants of ridersâ behaviour in relation to the social context of riding including social and identity-related influences relating to the group (group norms and group identity) as well as the self (moral/personal norm and self-identity). ----- ----- Method: Qualitative research was undertaken via group discussions with motorcycle riders (n = 41). Results: The findings revealed that those in the group with which one rides represent an important source of social influence. Also, the motorcyclist (group) identity was associated with a range of beliefs, expectations, and behaviours considered to be normative. Exploration of the construct of personal norm revealed that riders were most cognizant of the âwrong things to doâ when riding; among those issues raised was the importance of protective clothing (albeit for the protection of others and, in particular, pillion passengers). Finally, self-identity as a motorcyclist appeared to be important to a riderâs self-concept and was likely to influence their on-road behaviour. ----- ----- Conclusion: Overall, the insight provided by the current study may facilitate the development of interventions including rider training as well as public education and mass media messages. The findings suggest that these interventions should incorporate factors associated with the social nature of riding in order to best align it with some of the key beliefs and motivations underpinning ridersâ on-road behaviours
Flipping exciton angular momentum with chiral phonons in MoSe/WSe heterobilayers
Identifying quantum numbers to label elementary excitations is essential for
the correct description of light-matter interaction in solids. In monolayer
semiconducting transition metal dichalcogenides (TMDs) such as MoSe or
WSe, most optoelectronic phenomena are described well by labelling electron
and hole states with the spin projection along the normal to the layer (S).
In contrast, for WSe/MoSe interfaces recent experiments show that
taking S as quantum number is not a good approximation, and spin mixing
needs to be always considered. Here we argue that the correct quantum number
for these systems is not S, but the -component of the total angular
momentum -- J = L + S -- associated to the C rotational lattice
symmetry, which assumes half-integer values corresponding modulo 3 to distinct
states. We validate this conclusion experimentally through the observation of
strong intervalley scattering mediated by chiral optical phonons that --
despite carrying angular momentum 1 -- cause resonant intervalley transitions
of excitons, with an angular momentum difference of 2.Comment: are welcom
Seamless Gene Tagging by Endonuclease-Driven Homologous Recombination
Gene tagging facilitates systematic genomic and proteomic analyses but chromosomal tagging typically disrupts gene regulatory sequences. Here we describe a seamless gene tagging approach that preserves endogenous gene regulation and is potentially applicable in any species with efficient DNA double-strand break repair by homologous recombination. We implement seamless tagging in Saccharomyces cerevisiae and demonstrate its application for protein tagging while preserving simultaneously upstream and downstream gene regulatory elements. Seamless tagging is compatible with high-throughput strain construction using synthetic genetic arrays (SGA), enables functional analysis of transcription antisense to open reading frames and should facilitate systematic and minimally-invasive analysis of gene functions
Safety and efficacy of oral fexinidazole in children with gambiense human African trypanosomiasis: a multicentre, single-arm, open-label, phase 2-3 trial
BACKGROUND: Fexinidazole has been reported as an effective oral monotherapy against non-severe gambiense human African trypanosomiasis in a recent trial in adults. We aimed to assess the safety and efficacy of fexinidazole in children across all disease stages of gambiense human African trypanosomiasis. METHODS: We did a multicentre, single-arm, open-label, phase 2-3 trial at eight district hospitals in the Democratic Republic of the Congo. We recruited children with a Karnofsky score of more than 50, those aged 6 years to younger than 15 years, weighing 20 kg or more, and with confirmed gambiense human African trypanosomiasis (any stage). Children weighing 20 kg or more and less than 35 kg received oral fexinidazole of 1200 mg (two x 600 mg tablets) once per day for 4 days (days 1-4) followed by 600 mg (one x 600 mg tablet) once per day for 6 days (days 5-10). Children weighing 35 kg or more received oral fexinidazole of 1800 mg (three x 600 mg tablets) once per day for 4 days (days 1-4), followed by 1200 mg (two x 600 mg tablets) once per day for 6 days (days 5-10). The primary endpoint was fexinidazole treatment success rate 12 months after end of treatment. A rate greater than 80% was deemed acceptable and a target value of 92% was aimed for. Safety was assessed through routine monitoring. This study is completed and registered with ClinicalTrials.gov, number NCT02184689. FINDINGS: Between May 3, 2014, and Nov 22, 2016, we screened a total of 130 paediatric patients, of whom 125 (96%) received at least one dose of fexinidazole. All 125 patients (69 [55%] patients with stage 1, 19 [15%] with early stage 2, and 37 [30%] with late stage 2 gambiense human African trypanosomiasis) completed the 10-day treatment. Treatment success rate at 12 months was 97.6% (95% CI 93.1-99.5; 122 of 125 patients). The primary endpoint was met and the targeted value of 92% was exceeded. Treatment success at 12 months was elevated across all disease stages: 98.6% (95% CI 92.2-99.9; 68 of 69 patients) in stage 1, 94.7% (74.0-99.9; 18 of 19 patients) in early stage 2, and 97.3% (85.8-99.9; 36 of 37 patients) in late stage 2 gambiense human African trypanosomiasis. No new safety issues were observed beyond those found in adult trials. Overall, 116 (93%) of 125 patients reported 586 treatment-emergent adverse events, mainly mild or moderate. The most frequently reported treatment-emergent adverse events of interest during hospital admission were vomiting (86 [69%] of 125) and headache (41 [33%]). Seven (6%) of 125 patients had severe malaria, which was often accompanied by anaemia that was unrelated to fexinidazole. One patient died following dyspnoea and injury due to traumatic aggression 172 days after end of treatment, which was considered unrelated to fexinidazole or gambiense human African trypanosomiasis. INTERPRETATION: Oral fexinidazole is a safe and effective first-line treatment option across all gambiense human African trypanosomiasis disease stages in paediatric patients. FUNDING: Through the Drugs for Neglected Diseases initiative: the Bill & Melinda Gates Foundation (USA), the Republic and Canton of Geneva (Switzerland), the Dutch Ministry of Foreign Affairs (Netherlands), the Norwegian Agency for Development Cooperation (Norway), the Federal Ministry of Education and Research through KfW (Germany), the Brian Mercer Charitable Trust (UK), and other private foundations and individuals from the human African trypanosomiasis campaign. TRANSLATION: For the French translation of the abstract see Supplementary Materials section
Efficacy and safety of acoziborole in patients with human African trypanosomiasis caused by Trypanosoma brucei gambiense: a multicentre, open-label, single-arm, phase 2/3 trial
Summary Background Human African trypanosomiasis caused by Trypanosoma brucei gambiense (gambiense HAT) in patients with late-stage disease requires hospital admission to receive nifurtimox-eflornithine combination therapy (NECT). Fexinidazole, the latest treatment that has been recommended by WHO, also requires systematic admission to hospital, which is problematic in areas with few health-care resources. We aim to assess the safety and efficacy of acoziborole in adult and adolescent patients with gambiense HAT. Methods This multicentre, prospective, open-label, single-arm, phase 2/3 study recruited patients aged 15 years or older with confirmed gambiense HAT infection from ten hospitals in the Democratic Republic of the Congo and Guinea. Inclusion criteria included a Karnofsky score less than 50, ability to swallow tablets, a permanent address or traceability, ability to comply with follow-up visits and study requirements, and agreement to hospital admission during treatment. Oral acoziborole was administered as a single 960 mg dose (3 à 320 mg tablets) to fasted patients. Patients were observed in hospital until day 15 after treatment administration then for 18 months as outpatients with visits at 3, 6, 12, and 18 months. The primary efficacy endpoint was the success rate of acoziborole treatment at 18 months in patients with late-stage gambiense HAT (modified intention-to-treat [mITT] population), based on modified WHO criteria. A complementary post-hoc analysis comparing the 18-month success rates for acoziborole and NECT (using historical data) was performed. This study is registered at ClinicalTrials.gov, NCT03087955. Findings Between Oct 11, 2016, and March 25, 2019, 260 patients were screened, of whom 52 were ineligible and 208 were enrolled (167 with late-stage and 41 with early-stage or intermediate-stage gambiense HAT; primary efficacy analysis set). All 41 (100%) patients with early-stage or intermediate-stage and 160 (96%) of 167 with late-stage disease completed the last 18-month follow-up visit. The mean age of participants was 34·0 years (SD 12·4), including 117 (56%) men and 91 (44%) women. Treatment success rate at 18 months was 95·2% (95% CI 91·2-97·7) reached in 159 of 167 patients with late-stage gambiense HAT (mITT population) and 98·1% (95·1-99·5) reached in 159 of 162 patients (evaluable population). Overall, 155 (75%) of 208 patients had 600 treatment-emergent adverse events. A total of 38 drug-related treatment-emergent adverse events occurred in 29 (14%) patients; all were mild or moderate and most common were pyrexia and asthenia. Four deaths occurred during the study; none were considered treatment related. The post-hoc analysis showed similar results to the estimated historical success rate for NECT of 94%. Interpretation Given the high efficacy and favourable safety profile, acoziborole holds promise in the efforts to reach the WHO goal of interrupting HAT transmission by 2030. Funding Bill & Melinda Gates Foundation, UK Aid, Federal Ministry of Education and Research, Swiss Agency for Development and Cooperation, Médecins Sans FrontiÚres, Dutch Ministry of Foreign Affairs, Norwegian Agency for Development Cooperation, Norwegian Ministry of Foreign Affairs, the Stavros Niarchos Foundation, Spanish Agency for International Development Cooperation, and the Banco Bilbao Vizcaya Argentaria Foundation. Translation For the French translation of the abstract see Supplementary Materials section
Wet deposition of hydrocarbons in the city of Tehran-Iran
Air pollution in the city of Tehran has been a major problem for the past three decades. The direct effects of hydrocarbon contaminants in the air are particularly important such as their carcinogenic, mutagenic, and teratogenic effects which can be transported to other environments via dry and wet deposition. In the present study, rainwater samples were collected and analyzed for 16 polycyclic aromatic hydrocarbons (PAHs), benzene, toluene, ethyl benzene, and xylene (BTEX) as well as fuel fingerprints in two ranges of gasoline (C5âC11) and diesel fuel (C12âC20) using a gas chromatograph equipped with a flame ionization detector (GC/FID). Mean concentrations of â16 PAHs varied between 372 and 527 ”g/L and for BTEX was between 87 and 188 ”g/L with maximum of 36 ”g/L for toluene. Both gasoline range hydrocarbons (GRH) and diesel range hydrocarbons (DRH) were also present in the collected rainwater at concentrations of 190 and 950 ”g/L, respectively. Hydrocarbon transports from air to soil were determined in this wet deposition. Average hydrocarbon transportation for âPAHs, BTEX, GRH, and DRH was 2,747, 627, 1,152, and 5,733 ”g/m2, respectively
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