Analysis of caesarean section and neonatal outcome using the Robson classification in a rural district hospital in Tanzania: An observational retrospective study

OBJECTIVE: Caesarean section (CS) rates have increased worldwide in recent decades. In 2015, the WHO proposed the use of the 10-group Robson classification as a global standard for assessing, monitoring and comparing CS rates both within healthcare facilities over time and between them. The aim of this study was to assess the pattern of CS rates according to the Robson classification and describe maternal and perinatal outcomes by group at the Tosamaganga Hospital in rural Tanzania. DESIGN: Observational retrospective study. SETTING: St. John of the Cross Tosamaganga Hospital, a referral centre in rural Tanzania. PARTICIPANTS: 3012 women who gave birth in Tosamaganga Hospital from 1 January to 30 June 2014 and from 1 March to 30 November 2015. RESULTS: The overall CS rate was 35.2%, and about 90% of women admitted for labour were in Robson groups 1 through 5. More than 40% of the CS carried out in the hospital were performed on nulliparous women at term with a single fetus in cephalic presentation (groups 1 and 3), and the most frequent indication for the procedure was previous uterine scar (39.2%). The majority of severe neonatal outcomes were observed in groups 1 (27.7%), 10 (24.5%) and 3 (19.1%). CONCLUSION: We recorded a high CS rate in Tosamaganga Hospital, particularly in low-risk patients groups (Robson groups 1 and 3). Our analysis of Robson classification and neonatal outcomes suggests the need to improve labour management at the hospital and to provide timely referrals in order to prevent women from arriving there in critical conditions

Classifications for Cesarean Section: A Systematic Review

Background: Rising cesarean section (CS) rates are a major public health concern and cause worldwide debates. To propose and implement effective measures to reduce or increase CS rates where necessary requires an appropriate classification. Despite several existing CS classifications, there has not yet been a systematic review of these. This study aimed to 1) identify the main CS classifications used worldwide, 2) analyze advantages and deficiencies of each system.Methods and Findings: Three electronic databases were searched for classifications published 1968-2008. Two reviewers independently assessed classifications using a form created based on items rated as important by international experts. Seven domains (ease, clarity, mutually exclusive categories, totally inclusive classification, prospective identification of categories, reproducibility, implementability) were assessed and graded. Classifications were tested in 12 hypothetical clinical case-scenarios. From a total of 2948 citations, 60 were selected for full-text evaluation and 27 classifications identified. Indications classifications present important limitations and their overall score ranged from 2-9 (maximum grade = 14). Degree of urgency classifications also had several drawbacks (overall scores 6-9). Woman-based classifications performed best (scores 5-14). Other types of classifications require data not routinely collected and may not be relevant in all settings (scores 3-8).Conclusions: This review and critical appraisal of CS classifications is a methodologically sound contribution to establish the basis for the appropriate monitoring and rational use of CS. Results suggest that women-based classifications in general, and Robson's classification, in particular, would be in the best position to fulfill current international and local needs and that efforts to develop an internationally applicable CS classification would be most appropriately placed in building upon this classification. the use of a single CS classification will facilitate auditing, analyzing and comparing CS rates across different settings and help to create and implement effective strategies specifically targeted to optimize CS rates where necessary.Universidade Federal de São Paulo, Dept Obstet, São Paulo, BrazilBrazilian Cochrane Ctr, São Paulo, BrazilWorld Hlth Org, Dept Reprod Hlth & Res, Geneva, SwitzerlandWorld Hlth Org, Dept Knowledge Management & Sharing, Geneva, SwitzerlandUniversidade Federal de São Paulo, Dept Obstet, São Paulo, BrazilWeb of Scienc

Population genomics provide insights into the global genetic structure of Colletotrichum graminicola, the causal agent of maize anthracnose

Understanding the genetic diversity and mechanisms underlying genetic variation in pathogen populations is crucial to the development of effective control strategies. We investigated the genetic diversity and reproductive biology of Colletotrichum graminicola isolates which infect maize by sequencing the genomes of 108 isolates collected from 14 countries using restriction site-associated DNA sequencing (RAD-seq) and whole-genome sequencing (WGS). Clustering analyses based on single-nucleotide polymorphisms revealed three genetic groups delimited by continental origin, compatible with short-dispersal of the pathogen and geographic subdivision. Intra- and intercontinental migration was observed between Europe and South America, likely associated with the movement of contaminated germplasm. Low clonality, evidence of genetic recombination, and high phenotypic diversity were detected. We show evidence that, although it is rare (possibly due to losses of sexual reproduction- and meiosis-associated genes) C. graminicola can undergo sexual recombination. Our results support the hypotheses that intra- and intercontinental pathogen migration and genetic recombination have great impacts on the C. graminicola population structure

Large introns in relation to alternative splicing and gene evolution: a case study of Drosophila bruno-3

Background: Alternative splicing (AS) of maturing mRNA can generate structurally and functionally distinct transcripts from the same gene. Recent bioinformatic analyses of available genome databases inferred a positive correlation between intron length and AS. To study the interplay between intron length and AS empirically and in more detail, we analyzed the diversity of alternatively spliced transcripts (ASTs) in the Drosophila RNA-binding Bruno-3 (Bru-3) gene. This gene was known to encode thirteen exons separated by introns of diverse sizes, ranging from 71 to 41,973 nucleotides in D. melanogaster. Although Bru-3's structure is expected to be conducive to AS, only two ASTs of this gene were previously described. Results: Cloning of RT-PCR products of the entire ORF from four species representing three diverged Drosophila lineages provided an evolutionary perspective, high sensitivity, and long-range contiguity of splice choices currently unattainable by high-throughput methods. Consequently, we identified three new exons, a new exon fragment and thirty-three previously unknown ASTs of Bru-3. All exon-skipping events in the gene were mapped to the exons surrounded by introns of at least 800 nucleotides, whereas exons split by introns of less than 250 nucleotides were always spliced contiguously in mRNA. Cases of exon loss and creation during Bru-3 evolution in Drosophila were also localized within large introns. Notably, we identified a true de novo exon gain: exon 8 was created along the lineage of the obscura group from intronic sequence between cryptic splice sites conserved among all Drosophila species surveyed. Exon 8 was included in mature mRNA by the species representing all the major branches of the obscura group. To our knowledge, the origin of exon 8 is the first documented case of exonization of intronic sequence outside vertebrates. Conclusion: We found that large introns can promote AS via exon-skipping and exon turnover during evolution likely due to frequent errors in their removal from maturing mRNA. Large introns could be a reservoir of genetic diversity, because they have a greater number of mutable sites than short introns. Taken together, gene structure can constrain and/or promote gene evolution

Одноколейные тракторно-ледяные дороги: учебное пособие для лесотехнических вузов

Книга содержит описание конструкций однополозных тракторных саней, расчет основных деталей саней, краткие технические условия проектирования одноколейных тракторно-ледяных дорог, правила постройки и эксплуатации ледяных дорог и основы организации тракторного хозяйства на базе одноколейных ледяных дорог. Книга предназначена в качестве учебного пособия для лесотехнических вузов, но может также служить практическим пособием и для высшего технического персонала лесозаготовительных предприятий Наркомлеса СССР.0|7|Предисловие [c. 7]0|8|Введение [c. 8]0|11|Возникновение и развитие конструкции однополозных саней [c. 11]1|11|Первые опыты [c. 11]1|12|Принцип работы одноколейной ледяной дороги и теоретические основания проектирования однополозных саней [c. 12]1|17|Конструкция первых однополозных саней [c. 17]1|17|Однополозные сани Востокостальлеса [c. 17]1|19|Одкополозные сани ЦНИИМЭ, модель Б [c. 19]1|21|Однополозные сани на базе поковок тракторных двухполозных саней модели Д [c. 21]1|22|Однополозные сани Я. И. Гинзбурга модели 1939 г. [c. 22]1|33|Однополозные сани ГЗЯ-2 [c. 33]1|39|Варианты соединения коника с полозом [c. 39]1|39|Модернизированные однополозные сани на базе поковок саней модели Свердлеса и Востокостальлеса [c. 39]1|44|Бескониковые однополозные сани конструкции СибНИИЛХЭ [c. 44]1|46|Буферно-прицепные устройства трактора конструкции УЛТИ, Сотринского мехлесопункта и Стройлеспроекта [c. 46]1|48|Автоматическая сцепка тракторных саней [c. 48]1|49|Рама для перевозки коротья на однополозных санях [c. 49]1|51|Расчет саней [c. 51]1|51|Расчет полоза [c. 51]1|58|О форме подрезов [c. 58]0|61|Постройка одноколейных ледяных дорог [c. 61]1|61|Условия применения, сырьевая база и порядок оформления строительства [c. 61]1|62|Технические условия проектирования одноколейных ледяных дорог [c. 62]1|72|Изыскания трасс одноколейных ледяных дорог [c. 72]1|73|Строительные работы на одноколейных ледяных дорогах [c. 73]1|85|Дорожные орудия для строительства одноколейных ледяных дорог [c. 85]1|91|Цистерны для поливки ледяной дороги [c. 91]1|91|Насосные станции [c. 91]0|95|Эксплуатация ледяных дорог [c. 95]1|95|Техническая характеристика тяговых машин [c. 95]1|107|Эксплуатация газогенераторных тракторов на лесовывозке по ледяным дорогам [c. 107]1|115|Правила вождения поездов [c. 115]1|117|Формирование состава и маневры [c. 117]1|117|Содержание и ремонт пути ледяной дороги [c. 117]1|119|Техника безопасности при вывозке леса по тракторным ледяным дорогам [c. 119]1|121|Основные правила по технике безопасности для тракторного лесотранспорта [c. 121]0|123|Приложения [c. 123]1|123|Детали однополозных саней ГЗЯ-1 [c. 123]1|136|Детали модернизированных однополозных саней на базе поковок саней Свердллеса [c. 136]1|141|Краткая техническая характеристика гусеничных тракторов Челябинского тракторного завода [c. 141]0|143|Оглавление [c. 143

Large-Scale Selective Sweep among Segregation Distorter Chromosomes in African Populations of Drosophila melanogaster

Segregation Distorter (SD) is a selfish, coadapted gene complex on chromosome 2 of Drosophila melanogaster that strongly distorts Mendelian transmission; heterozygous SD/SD+ males sire almost exclusively SD-bearing progeny. Fifty years of genetic, molecular, and theory work have made SD one of the best-characterized meiotic drive systems, but surprisingly the details of its evolutionary origins and population dynamics remain unclear. Earlier analyses suggested that the SD system arose recently in the Mediterranean basin and then spread to a low, stable equilibrium frequency (1–5%) in most natural populations worldwide. In this report, we show, first, that SD chromosomes occur in populations in sub-Saharan Africa, the ancestral range of D. melanogaster, at a similarly low frequency (∼2%), providing evidence for the robustness of its equilibrium frequency but raising doubts about the Mediterranean-origins hypothesis. Second, our genetic analyses reveal two kinds of SD chromosomes in Africa: inversion-free SD chromosomes with little or no transmission advantage; and an African-endemic inversion-bearing SD chromosome, SD-Mal, with a perfect transmission advantage. Third, our population genetic analyses show that SD-Mal chromosomes swept across the African continent very recently, causing linkage disequilibrium and an absence of variability over 39% of the length of the second chromosome. Thus, despite a seemingly stable equilibrium frequency, SD chromosomes continue to evolve, to compete with one another, or evade suppressors in the genome

Population genomics provide insights into the global genetic structure of Colletotrichum graminicola, the causal agent of maize anthracnose.

Abstract: Understanding the genetic diversity and mechanisms underlying genetic variation in pathogen populations is crucial to the development of effective control strategies. We investigated the genetic diversity and reproductive biology of Colletotrichum graminicola isolates which infect maize by sequencing the genomes of 108 isolates collected from 14 countries using restriction site-associated DNA sequencing (RAD-seq) and whole-genome sequencing (WGS). Clustering analyses based on single-nucleotide polymorphisms revealed three genetic groups delimited by continental origin, compatible with short-dispersal of the pathogen and geographic subdivision. Intra- and intercontinental migration was observed between Europe and South America, likely associated with the movement of contaminated germplasm. Low clonality, evidence of genetic recombination, and high phenotypic diversity were detected. We show evidence that, although it is rare (possibly due to losses of sexual reproduction- and meiosis-associated genes) C. graminicola can undergo sexual recombination. Our results support the hypotheses that intra- and intercontinental pathogen migration and genetic recombination have great impacts on the C. graminicola population structure. Importance: Plant pathogens cause significant reductions in yield and crop quality and cause enormous economic losses worldwide. Reducing these losses provides an obvious strategy to increase food production without further degrading natural ecosystems; however, this requires knowledge of the biology and evolution of the pathogens in agroecosystems. We employed a population genomics approach to investigate the genetic diversity and reproductive biology of the maize anthracnose pathogen (Colletotrichum graminicola) in 14 countries. We found that the populations are correlated with their geographical origin and that migration between countries is ongoing, possibly caused by the movement of infected plant material. This result has direct implications for disease management because migration can cause the movement of more virulent and/or fungicide-resistant genotypes. We conclude that genetic recombination is frequent (in contrast to the traditional view of C. graminicola being mainly asexual), which strongly impacts control measures and breeding programs aimed at controlling this disease.On-line first

Migration and genetic recombination shape the global population structure of Colletotrichum graminicola, the causal agent of maize anthracnose.

Maize anthracnose, caused by the ascomycete fungus Colletotrichum graminicola, is an important crop disease worldwide. Understanding the genetic diversity and mechanisms underlying genetic variation in pathogen populations is crucial to the development of effective control strategies. The genus Colletotrichum is largely recognized as asexual, but several species have been reported to have a sexual cycle. We employed a population genomics approach to investigate the genetic diversity and reproductive biology of C. graminicola isolates infecting maize. We sequenced 108 isolates of C. graminicola collected in 14 countries using restriction site-associated DNA sequencing (RAD-Seq) and whole-genome sequencing (WGS). Clustering analyses based on single-nucleotide polymorphisms showed populational differentiation at a global scale, with three genetic groups delimited by continental origin, corresponding to the isolates from South America, Europe, and North America, compatible with short-dispersal of the pathogen, and geographic subdivision. Intra and inter-continental migration was predicted between Europe and South America, likely associated with the movement of contaminated germplasm. Low clonality and evidence of genetic recombination were detected from the analysis of linkage disequilibrium and the pairwise homoplasy index (PHI) test for clonality. Although the sexual state of C. graminicola has only been reported in lab conditions, we showed strong evidence that genetic recombination have a great impact on C. graminicola population structure, in contrast to the traditional view of C. graminicola being mainly clonal