Transcriptional profiling in response to terminal drought stress reveals differential responses along the wheat genome

Background: Water stress during grain filling has a marked effect on grain yield, leading to a reduced endosperm cell number and thus sink capacity to accumulate dry matter. The bread wheat cultivar Chinese Spring (CS), a Chinese Spring terminal deletion line (CS_5AL-10) and the durum wheat cultivar Creso were subjected to transcriptional profiling after exposure to mild and severe drought stress at the grain filling stage to find evidences of differential stress responses associated to different wheat genome regions. Results: The transcriptome analysis of Creso, CS and its deletion line revealed 8,552 non redundant probe sets with different expression levels, mainly due to the comparisons between the two species. The drought treatments modified the expression of 3,056 probe sets. Besides a set of genes showing a similar drought response in Creso and CS, cluster analysis revealed several drought response features that can be associated to the different genomic structure of Creso, CS and CS_5AL-10. Some drought-related genes were expressed at lower level (or not expressed) in Creso (which lacks the D genome) or in the CS_5AL- 10 deletion line compared to CS. The chromosome location of a set of these genes was confirmed by PCR-based mapping on the D genome (or the 5AL-10 region). Many clusters were characterized by different level of expression in Creso, CS and CS_AL-10, suggesting that the different genome organization of the three genotypes may affect plant adaptation to stress. Clusters with similar expression trend were grouped and functional classified to mine the biological mean of their activation or repression. Genes involved in ABA, proline, glycine-betaine and sorbitol pathways were found up-regulated by drought stress. Furthermore, the enhanced expression of a set of transposons and retrotransposons was detected in CS_5AL-10. Conclusion: Bread and durum wheat genotypes were characterized by a different physiological reaction to water stress and by a substantially different molecular response. The genome organization accounted for differences in the expression level of hundreds of genes located on the D genome or controlled by regulators located on the D genome. When a genomic stress (deletion of a chromosomal region) was combined with low water availability, a molecular response based on the activation of transposons and retrotransposons was observed

Risk of SARS-CoV-2 infection among front-line healthcare workers in Northeast Brazil : a respondent-driven sampling approach

Objectives We assessed the prevalence of SARS-CoV-2 infection, personal protective equipment (PPE) shortages and occurrence of biological accidents among front-line healthcare workers (HCW). Design, setting and participants Using respondent-driven sampling, the study recruited distinct categories of HCW attending suspected or confirmed patients with COVID-19 from May 2020 to February 2021, in the Recife metropolitan area, Northeast Brazil. Outcome measures The criterion to assess SARS-CoV-2 infection among HCW was a positive self-reported PCR test. Results We analysed 1525 HCW: 527 physicians, 471 registered nurses, 263 nursing assistants and 264 physical therapists. Women predominated in all categories (81.1%; 95% CI: 77.8% to 84.1%). Nurses were older with more comorbidities (hypertension and overweight/obesity) than the other staff. The overall prevalence of SARS-CoV-2 infection was 61.8% (95% CI: 55.7% to 67.5%) after adjustment for the cluster random effect, weighted by network, and the reference population size. Risk factors for a positive RT-PCR test were being a nursing assistant (OR adjusted: 2.56; 95% CI: 1.42 to 4.61), not always using all recommended PPE while assisting patients with COVID-19 (OR adj: 2.15; 95% CI: 1.02 to 4.53) and reporting a splash of biological fluid/respiratory secretion in the eyes (OR adj: 3.37; 95% CI: 1.10 to 10.34). Conclusions This study shows the high frequency of SARS-CoV2 infection among HCW presumably due to workplace exposures. In our setting, nursing assistant comprised the most vulnerable category. Our findings highlight the need for improving healthcare facility environments, specific training and supervision to cope with public health emergencies

Understanding the relation between Zika virus infection during pregnancy and adverse fetal, infant and child outcomes: a protocol for a systematic review and individual participant data meta-analysis of longitudinal studies of pregnant women and their infants and children

IntroductionZika virus (ZIKV) infection during pregnancy is a known cause of microcephaly and other congenital and developmental anomalies. In the absence of a ZIKV vaccine or prophylactics, principal investigators (PIs) and international leaders in ZIKV research have formed the ZIKV Individual Participant Data (IPD) Consortium to identify, collect and synthesise IPD from longitudinal studies of pregnant women that measure ZIKV infection during pregnancy and fetal, infant or child outcomes.Methods and analysisWe will identify eligible studies through the ZIKV IPD Consortium membership and a systematic review and invite study PIs to participate in the IPD meta-analysis (IPD-MA). We will use the combined dataset to estimate the relative and absolute risk of congenital Zika syndrome (CZS), including microcephaly and late symptomatic congenital infections; identify and explore sources of heterogeneity in those estimates and develop and validate a risk prediction model to identify the pregnancies at the highest risk of CZS or adverse developmental outcomes. The variable accuracy of diagnostic assays and differences in exposure and outcome definitions means that included studies will have a higher level of systematic variability, a component of measurement error, than an IPD-MA of studies of an established pathogen. We will use expert testimony, existing internal and external diagnostic accuracy validation studies and laboratory external quality assessments to inform the distribution of measurement error in our models. We will apply both Bayesian and frequentist methods to directly account for these and other sources of uncertainty.Ethics and disseminationThe IPD-MA was deemed exempt from ethical review. We will convene a group of patient advocates to evaluate the ethical implications and utility of the risk stratification tool. Findings from these analyses will be shared via national and international conferences and through publication in open access, peer-reviewed journals.Trial registration numberPROSPERO International prospective register of systematic reviews (CRD42017068915).</jats:sec

Localization of new peptidoglycan at poles in Bacillus mycoides, a member of the Bacillus cereus group

Bacillus mycoides is a sporogenic Gram-positive soil bacillus of the B. cereus group. This bacillus, which forms hyphal colonies, is composed of cells connected in filaments that make up bundles and turn clock- or counterclockwise depending on the strain. A thick peptidoglycan wall gives the rod cells of these bacilli strength and shape. One approach used to study peptidoglycan neoformation in Gram positives exploits the binding properties of antibiotics such as vancomycin and ramoplanin to nascent peptidoglycan, whose localization in the cell is monitored by means of a fluorescent tag. When we treated B. mycoides strains with BODIPY-vancomycin, we found the expected accumulation of fluorescence at the midcell septa and localization along the cell sidewall in small foci distributed quite uniformly. Intense fluorescence was also observed at the poles of many cells, more clearly visible at the outer edges of the cell chains. The unusual abundance of peptidoglycan intermediates at the cell poles after cell separation suggests that the construction process of this structure is different from that of B. subtilis, in which the free poles are rarely reactive to vancomycin

Transcriptional analysis of ftsZ within the dcw cluster in Bacillus mycoides

Background: In Bacillus mycoides, as well as in other members of the B. cereus group, the tubulin-like protein of the division septum FtsZ is encoded by the distal gene of the cluster division and cell wall (dcw). Along the cluster the genes coding for structural proteins of the division apparatus are intermingled with those coding for enzymes of peptidoglycan biosynthesis, raising the possibility that genes with this different function might be coexpressed. Transcription of ftsZ in two model bacteria had been reported to differ: in B. subtilis, the ftsZ gene was found transcribed as a bigenic mRNA in the AZ operon; in E. coli, the transcripts of ftsZ were monogenic, expressed by specific promoters. Here we analyzed the size and the initiation sites of RNAs transcribed from ftsZ and from other cluster genes in two B. mycoides strains, DX and SIN, characterized by colonies of different chirality and density, to explore the correlation of the different morphotypes with transcription of the dcw genes. Results: In both strains, during vegetative growth, the ftsZ-specific RNAs were composed mainly of ftsZ, ftsA-ftsZ and ftsQ-ftsA-ftsZ transcripts. A low number of RNA molecules included the sequences of the upstream murG and murB genes, which are involved in peptidoglycan synthesis. No cotranscription was detected between ftsZ and the downstream genes of the SpoIIG cluster. The monogenic ftsZ RNA was found in both strains, with the main initiation site located inside the ftsA coding sequence. To confirm the promoter property of the site, a B. mycoides construct carrying the ftsA region in front of the shortened ftsZ gene was inserted into the AmyE locus of B. subtilis 168. The promoter site in the ftsA region was recognized in the heterologous cellular context and expressed as in B. mycoides. Conclusions: The DX and SIN strains of B. mycoides display very similar RNA transcription specificity. The ftsZ messenger RNA can be found either as an independent transcript or expressed together with ftsA and ftsQ and, in low amounts, with genes that are specific to peptidoglycan biosynthesis

Reports from the frontline: health workers describe COVID-19 risks and fears in five cities in Brazil

National Council for Science and Technological Development, CNPq 402403/2020–7Tulane University. School of Public Health and Tropical Medicine. New Orleans, LA, USA / Federal University of Ceará. Programa de Pós-Graduação Em Saúde Pública. Fortaleza, CE, Brazil.Federal University of Ceará. Programa de Pós-Graduação Em Saúde Pública. Fortaleza, CE, Brazil.Faculdade de Ciências Médicas da Santa Casa de São Paulo. São Paulo, SP, Brazil.Federal University of Ceará. Programa de Pós-Graduação Em Saúde Pública. Fortaleza, CE, Brazil.Federal University of Rio Grande do Sul. Porto Alegre, RS, Brazil.Federal University of Rio Grande do Sul. Porto Alegre, RS, Brazil.Federal University of Ceará. Programa de Pós-Graduação Em Saúde Pública. Fortaleza, CE, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Faculdade de Ciências Médicas da Santa Casa de São Paulo. São Paulo, SP, Brazil.Oswaldo Cruz Foundation. Recife, PE, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Oswaldo Cruz Foundation. Recife, PE, Brazil.Federal University of Ceará. Programa de Pós-Graduação Em Saúde Pública. Fortaleza, CE, Brazil.Background: Health providers are under unprecedented pressures to perform in the COVID-19 health crisis and under unprecedented risks. We initiated a large mixed-method survey of health professionals in fve large metropolitan areas in Brazil to document the risks and needs of health professionals. To initiate the study, we conducted formative research. Methods: We conducted 77 open-ended semi-structured interviews online in a convenience sample of physicians, nurses, nurse technicians, and physiotherapists in Belem, Fortaleza, Porto Alegre, Recife, and São Paulo, Brazil. Design, data collection, and analysis were informed by Rapid Ethnographic Analysis (REA). Results: Responses are organized into three themes that emerged in the interviews: the lack of preparation – both locally and nationally—for the pandemic and its efects on stafng and training; the overlap of personal, family, and professional risk and consequences; and inadequately addressed anxiety and sufering among health staf. Conclusions: Our respondents were unprepared for the epidemic, especially the institutional sequelae and psychological cost. These consequences were exacerbated by both lack of leadership and sweeping changes undercutting the Brazilian health system noted by almost all participants

Risk of adverse outcomes in offspring with RT-PCR confirmed prenatal Zika virus exposure: an individual participant data meta-analysis of 13 cohorts in the Zika Brazilian Cohorts ConsortiumResearch in context

Summary: Background: Knowledge regarding the risks associated with Zika virus (ZIKV) infections in pregnancy has relied on individual studies with relatively small sample sizes and variable risk estimates of adverse outcomes, or on surveillance or routinely collected data. Using data from the Zika Brazilian Cohorts Consortium, this study aims, to estimate the risk of adverse outcomes among offspring of women with RT-PCR-confirmed ZIKV infection during pregnancy and to explore heterogeneity between studies. Methods: We performed an individual participant data meta-analysis of the offspring of 1548 pregnant women from 13 studies, using one and two-stage meta-analyses to estimate the absolute risks. Findings: Of the 1548 ZIKV-exposed pregnancies, the risk of miscarriage was 0.9%, while the risk of stillbirth was 0.3%. Among the pregnancies with liveborn children, the risk of prematurity was 10,5%, the risk of low birth weight was 7.7, and the risk of small for gestational age (SGA) was 16.2%. For other abnormalities, the absolute risks were: 2.6% for microcephaly at birth or first evaluation, 4.0% for microcephaly at any time during follow-up, 7.9% for neuroimaging abnormalities, 18.7% for functional neurological abnormalities, 4.0% for ophthalmic abnormalities, 6.4% for auditory abnormalities, 0.6% for arthrogryposis, and 1.5% for dysphagia. This risk was similar in all sites studied and in different socioeconomic conditions, indicating that there are not likely to be other factors modifying this association. Interpretation: This study based on prospectively collected data generates the most robust evidence to date on the risks of congenital ZIKV infections over the early life course. Overall, approximately one-third of liveborn children with prenatal ZIKV exposure presented with at least one abnormality compatible with congenital infection, while the risk to present with at least two abnormalities in combination was less than 1.0%. Funding: National Council for Scientific and Technological Development - Brazil (Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq); Wellcome Trust and the United Kingdom's Department for International Development; European Union's Horizon 2020 research and innovation program; Medical Research Council on behalf of the Newton Fund and Wellcome Trust; National Institutes of Health/National Institute of Allergy and Infectious Diseases; Foundation Christophe et Rodolphe Mérieux; Coordination for the improvement of Higher Education Personnel (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Capes); Ministry of Health of Brazil; Brazilian Department of Science and Technology; Foundation of Research Support of the State of São Paulo (Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP); Foundation of Research Support of the State of Rio de Janeiro (Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro – FAPERJ); Foundation of Support for Research and Scientific and Technological Development of Maranhão; Evandro Chagas Institute/Brazilian Ministry of Health (Instituto Evandro Chagas/Ministério da Saúde); Foundation of Research Support of the State of Goiás (Fundação de Amparo à Pesquisa do Estado de Goiás – FAPEG); Foundation of Research Support of the State of Rio Grande do Sul (Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul – FAPERGS); Foundation to Support Teaching, Research and Assistance at Hospital das Clínicas, Faculty of Medicine of Ribeirão Preto (Fundação de Apoio ao Ensino, Pesquisa e Assistência do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto); São Paulo State Department of Health (Secretaria de Saúde do Estado de São Paulo); Support Foundation of Pernambuco Science and Technology (Fundação de Amparo à Ciência e Tecnologia de Pernambuco – FACEPE)