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1.
Cell ; 186(16): 3414-3426.e16, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37541198

RESUMO

Lateral transduction (LT) is the process by which temperate phages mobilize large sections of bacterial genomes. Despite its importance, LT has only been observed during prophage induction. Here, we report that superantigen-carrying staphylococcal pathogenicity islands (SaPIs) employ a related but more versatile and complex mechanism of gene transfer to drive chromosomal hypermobility while self-transferring with additional virulence genes from the host. We found that after phage infection or prophage induction, activated SaPIs form concatamers in the bacterial chromosome by switching between parallel genomic tracks in replication bubbles. This dynamic life cycle enables SaPIbov1 to piggyback its LT of staphylococcal pathogenicity island vSaα, which encodes an array of genes involved in host-pathogen interactions, allowing both islands to be mobilized intact and transferred in a single infective particle. Our findings highlight previously unknown roles of pathogenicity islands in bacterial virulence and show that their evolutionary impact extends beyond the genes they carry.


Assuntos
Ilhas Genômicas , Fagos de Staphylococcus , Staphylococcus , Genoma Bacteriano , Staphylococcus/genética , Staphylococcus/patogenicidade , Virulência , Transdução Genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-38873725

RESUMO

INTRODUCTION: Twin-twin transfusion syndrome (TTTS) complicates approximately 10%-15% of all monochorionic twin pregnancies. The aim of this review was to evaluate the placental architectural characteristics within TTTS twins following laser and elucidate their impact on fetal outcomes and operative success. MATERIAL AND METHODS: Five databases were searched from inception to August 2023. Studies detailing post-delivery placental analysis within TTTS twins post-laser were included. Studies were categorized into two main groups: (1) residual anastomoses following laser and (2) abnormal cord insertion: either velamentous and/or marginal or proximate. The primary outcome was to determine the proportion of TTTS placentas with residual anastomoses and abnormal cord insertions post-laser. Secondary outcomes included assessing residual anastomoses on post-laser fetal outcomes and assessing the relationship between abnormal cord insertion and TTTS development. Study bias was critiqued using the Joanna Briggs Institute checklists and Cochrane risk of bias tool. Random-effects meta-analysis was used, and results were reported as pooled proportions or odds ratio (OR) with 95% confidence interval (CI). PROSPERO registration: CRD42023476875. RESULTS: Twenty-six studies, comprising 4013 monochorionic twins, were included for analysis. The proportion of TTTS placentas with residual anastomoses following laser was 24% (95% CI, 0.12-0.41), with a mean and standard deviation of 4.03 ± 2.95 anastomoses per placenta. Post-laser residual anastomoses were significantly associated with intrauterine fetal death (OR, 2.38 [95% CI, 1.33-4.26]), neonatal death (OR, 3.37 [95% CI, 1.65-6.88]), recurrent TTTS (OR, 24.33 [95% CI, 6.64-89.12]), and twin anemia polycythemia sequence (OR, 13.54 [95% CI, 6.36-28.85]). Combined abnormal cord (velamentous and marginal), velamentous cord, and marginal cord insertions within one or both twins following laser were reported at rates of 49% (95% CI, 0.39-0.59), 27% (95% CI, 0.18-0.38), and 28% (95% CI, 0.21-0.36), respectively. Combined, velamentous and marginal cord insertions were not significantly associated with TTTS twins requiring laser (p = 0.72, p = 0.38, and p = 0.71, respectively) versus non-TTTS monochorionic twins. CONCLUSIONS: To the best of our knowledge, this is the first review to conjointly explore outcomes of residual anastomoses and abnormal cord insertions within TTTS twins following laser. A large prospective study is necessitated to assess the relationship between abnormal cord insertion and residual anastomoses development post-laser.

3.
Cochrane Database Syst Rev ; 12: CD011689, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30569545

RESUMO

BACKGROUND: Postpartum haemorrhage (PPH) is the leading cause of maternal mortality worldwide. Prophylactic uterotonic agents can prevent PPH, and are routinely recommended. The current World Health Organization (WHO) recommendation for preventing PPH is 10 IU (international units) of intramuscular or intravenous oxytocin. There are several uterotonic agents for preventing PPH but there is still uncertainty about which agent is most effective with the least side effects. This is an update of a Cochrane Review which was first published in April 2018 and was updated to incorporate results from a recent large WHO trial. OBJECTIVES: To identify the most effective uterotonic agent(s) to prevent PPH with the least side effects, and generate a ranking according to their effectiveness and side-effect profile. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (24 May 2018), and reference lists of retrieved studies. SELECTION CRITERIA: All randomised controlled trials or cluster-randomised trials comparing the effectiveness and side effects of uterotonic agents with other uterotonic agents, placebo or no treatment for preventing PPH were eligible for inclusion. Quasi-randomised trials were excluded. Randomised trials published only as abstracts were eligible if sufficient information could be retrieved. DATA COLLECTION AND ANALYSIS: At least three review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We estimated the relative effects and rankings for preventing PPH ≥ 500 mL and PPH ≥ 1000 mL as primary outcomes. Secondary outcomes included blood loss and related outcomes, morbidity outcomes, maternal well-being and satisfaction and side effects. Primary outcomes were also reported for pre-specified subgroups, stratifying by mode of birth, prior risk of PPH, healthcare setting, dosage, regimen and route of administration. We performed pairwise meta-analyses and network meta-analysis to determine the relative effects and rankings of all available agents. MAIN RESULTS: The network meta-analysis included 196 trials (135,559 women) involving seven uterotonic agents and placebo or no treatment, conducted across 53 countries (including high-, middle- and low-income countries). Most trials were performed in a hospital setting (187/196, 95.4%) with women undergoing a vaginal birth (71.5%, 140/196).Relative effects from the network meta-analysis suggested that all agents were effective for preventing PPH ≥ 500 mL when compared with placebo or no treatment. The three highest ranked uterotonic agents for prevention of PPH ≥ 500 mL were ergometrine plus oxytocin combination, misoprostol plus oxytocin combination and carbetocin. There is evidence that ergometrine plus oxytocin (RR 0.70, 95% CI 0.59 to 0.84, moderate certainty), carbetocin (RR 0.72, 95% CI 0.56 to 0.93, moderate certainty) and misoprostol plus oxytocin (RR 0.70, 95% CI 0.58 to 0.86, low certainty) may reduce PPH ≥ 500 mL compared with oxytocin. Low-certainty evidence suggests that misoprostol, injectable prostaglandins, and ergometrine may make little or no difference to this outcome compared with oxytocin.All agents except ergometrine and injectable prostaglandins were effective for preventing PPH ≥ 1000 mL when compared with placebo or no treatment. High-certainty evidence suggests that ergometrine plus oxytocin (RR 0.83, 95% CI 0.66 to 1.03) and misoprostol plus oxytocin (RR 0.88, 95% CI 0.70 to 1.11) make little or no difference in the outcome of PPH ≥ 1000 mL compared with oxytocin. Low-certainty evidence suggests that ergometrine may make little or no difference to this outcome compared with oxytocin meanwhile the evidence on carbetocin was of very low certainty. High-certainty evidence suggests that misoprostol is less effective in preventing PPH ≥ 1000 mL when compared with oxytocin (RR 1.19, 95% CI 1.01 to 1.42). Despite the comparable relative treatment effects between all uterotonics (except misoprostol) and oxytocin, ergometrine plus oxytocin, misoprostol plus oxytocin combinations and carbetocin were the highest ranked agents for PPH ≥ 1000 mL.Misoprostol plus oxytocin reduces the use of additional uterotonics (RR 0.56, 95% CI 0.42 to 0.73, high certainty) and probably also reduces the risk of blood transfusion (RR 0.51, 95% CI 0.37 to 0.70, moderate certainty) when compared with oxytocin. Carbetocin, injectable prostaglandins and ergometrine plus oxytocin may also reduce the use of additional uterotonics but the certainty of the evidence is low. No meaningful differences could be detected between all agents for maternal deaths or severe morbidity as these outcomes were rare in the included randomised trials where they were reported.The two combination regimens were associated with important side effects. When compared with oxytocin, misoprostol plus oxytocin combination increases the likelihood of vomiting (RR 2.11, 95% CI 1.39 to 3.18, high certainty) and fever (RR 3.14, 95% CI 2.20 to 4.49, moderate certainty). Ergometrine plus oxytocin increases the likelihood of vomiting (RR 2.93, 95% CI 2.08 to 4.13, moderate certainty) and may make little or no difference to the risk of hypertension, however absolute effects varied considerably and the certainty of the evidence was low for this outcome.Subgroup analyses did not reveal important subgroup differences by mode of birth (caesarean versus vaginal birth), setting (hospital versus community), risk of PPH (high versus low risk for PPH), dose of misoprostol (≥ 600 mcg versus < 600 mcg) and regimen of oxytocin (bolus versus bolus plus infusion versus infusion only). AUTHORS' CONCLUSIONS: All agents were generally effective for preventing PPH when compared with placebo or no treatment. Ergometrine plus oxytocin combination, carbetocin, and misoprostol plus oxytocin combination may have some additional desirable effects compared with the current standard oxytocin. The two combination regimens, however, are associated with significant side effects. Carbetocin may be more effective than oxytocin for some outcomes without an increase in side effects.


Assuntos
Ergonovina/uso terapêutico , Misoprostol/uso terapêutico , Metanálise em Rede , Ocitócicos/uso terapêutico , Ocitocina/análogos & derivados , Ocitocina/uso terapêutico , Hemorragia Pós-Parto/prevenção & controle , Prostaglandinas/uso terapêutico , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Ergonovina/efeitos adversos , Feminino , Febre/induzido quimicamente , Humanos , Hipertensão/induzido quimicamente , Ocitocina/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Vômito/induzido quimicamente
4.
BMJ Open ; 14(5): e086724, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38803248

RESUMO

INTRODUCTION: Childbirth-related perineal trauma (CRPT) is the most common complication of childbirth affecting 80% of women overall after vaginal birth. There remains a lack of comprehensive evidence relating to the prevalence of subsequent health problems. Current evidence is related to short-term outcomes, for example, pain, but there is less known about longer-term outcomes such as infection, wound dehiscence, pelvic floor function and psychological outcomes. This is a protocol for a cohort study assessing outcomes of women after CRPT. METHODS AND ANALYSIS: A multicentre, prospective UK cohort study aiming to include 1000 women. All women who have sustained CRPT will be eligible for inclusion and will be followed-up for 12 months after childbirth. The primary outcome will be perineal infection at 6 weeks post-birth. Secondary outcomes will include antibiotic use for perineal infection, wound breakdown, use of analgesia, the requirement for admission or surgical intervention, urinary and faecal incontinence, anxiety and depressive symptoms, sexual function and impact on daily activities. Outcomes will be measured at 6 weeks, 6 months and 12 months post partum, with some outcomes being measured at all time points and others at selected most appropriate time points only. Outcome data will be obtained from a review of clinical notes and from patient questionnaires. Simple descriptive statistics will be used to summarise characteristics and outcomes, with categorical variables expressed as percentages and continuous variables as mean averages, alongside the corresponding standard deviatons. ETHICS AND DISSEMINATION: Ethical approval has been granted by the Research Ethics Council with reference 23/WA/0169. Data collected from the Childbirth Acquired Perineal Trauma (CHAPTER) cohort study will highlight the prevalence and type of complications after CRPT and which women are more at risk. After the conclusion of this study, findings will be used to work with governmental organisations and Royal Colleges to target resources and ultimately improve care.


Assuntos
Parto Obstétrico , Períneo , Humanos , Feminino , Períneo/lesões , Estudos Prospectivos , Reino Unido/epidemiologia , Gravidez , Parto Obstétrico/efeitos adversos , Complicações do Trabalho de Parto/epidemiologia , Projetos de Pesquisa , Adulto , Parto/psicologia
5.
Eur J Obstet Gynecol Reprod Biol ; 262: 105-112, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34010722

RESUMO

OBJECTIVE: To assess the effects of aspirin in pregnancy for the prevention of adverse outcomes in low risk, nulliparous women with singleton pregnancies. STUDY DESIGN: Medline, Embase, CINAHL, the Cochrane library, Web of Science and clinicaltrials.gov were searched from inception until February 2020. Randomised controlled trials were eligible for inclusion where women were nulliparous, had singleton pregnancies and no other risk factors for pre-eclampsia such as diabetes or pre-existing hypertension. Primary outcomes were pre-eclampsia, gestational hypertension and eclampsia. Secondary outcomes included; pre-term birth, postpartum haemorrhage, antepartum haemorrhage, miscarriage, small for gestational age (SGA), fetal growth restriction (FGR), birthweight and further markers of maternal and neonatal morbidity and mortality. The results were combined into meta-analysis where appropriate. RESULTS: Ten studies were eligible for inclusion involving 23,162 women. Two studies (involving 214 women) used aspirin doses of 100 mg, with the remainder using smaller doses. There was no significant difference found in the risk of developing pre-eclampsia between women receiving aspirin compared to no aspirin (relative risk [RR] 0.70, 95 % confidence interval [CI] 0.47-1.05, p = 0.08). Women receiving aspirin had a reduced risk of having a preterm birth <34 weeks (RR 0.50, 95 % CI 0.26-0.96, p = 0.04), and reduced risk of having a SGA neonate (RR 0.94, 95 % CI 0.89-1.00, p = 0.04). An increase in birthweight was seen when aspirin was received (mean difference 105.17 g, 95 % CI 12.38 g-197.96 g, p = 0.03) and there was no increase in risk of postpartum or antepartum haemorrhage in those receiving aspirin (RR 1.24, 95 % CI 0.90-1.71, p = 0.19 and RR 1.06, 95 % CI 0.66-1.70, p = 0.81 respectively). CONCLUSION: The results did not demonstrate a significant difference amongst low risk nulliparous women in the risks of pre-eclampsia or gestational hypertensive disorders with aspirin administration. Although we found significantly improved fetal growth parameters and prevention of preterm birth in women receiving aspirin, there were few eligible studies, with those included generally providing low quality evidence and many studies using aspirin doses ≤100 mg, commenced late in pregnancy. More research in the form of a high quality randomised controlled trial is needed before recommendations can be made.


Assuntos
Pré-Eclâmpsia , Nascimento Prematuro , Aspirina , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco
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