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1.
Nature ; 605(7910): 539-544, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35508655

RESUMO

Herpesviruses have mastered host cell modulation and immune evasion to augment productive infection, life-long latency and reactivation1,2. A long appreciated, yet undefined relationship exists between the lytic-latent switch and viral non-coding RNAs3,4. Here we identify viral microRNA (miRNA)-mediated inhibition of host miRNA processing as a cellular mechanism that human herpesvirus 6A (HHV-6A) exploits to disrupt mitochondrial architecture, evade intrinsic host defences and drive the switch from latent to lytic virus infection. We demonstrate that virus-encoded miR-aU14 selectively inhibits the processing of multiple miR-30 family members by direct interaction with the respective primary (pri)-miRNA hairpin loops. Subsequent loss of miR-30 and activation of the miR-30-p53-DRP1 axis triggers a profound disruption of mitochondrial architecture. This impairs induction of type I interferons and is necessary for both productive infection and virus reactivation. Ectopic expression of miR-aU14 triggered virus reactivation from latency, identifying viral miR-aU14 as a readily druggable master regulator of the herpesvirus lytic-latent switch. Our results show that miRNA-mediated inhibition of miRNA processing represents a generalized cellular mechanism that can be exploited to selectively target individual members of miRNA families. We anticipate that targeting miR-aU14 will provide new therapeutic options for preventing herpesvirus reactivations in HHV-6-associated disorders.


Assuntos
Herpesviridae , MicroRNAs , Herpesviridae/genética , Herpesviridae/metabolismo , Humanos , Evasão da Resposta Imune , MicroRNAs/genética , MicroRNAs/metabolismo , Interferência de RNA , Processamento Pós-Transcricional do RNA , Latência Viral/genética
2.
Can J Neurol Sci ; : 1-11, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38361453

RESUMO

Guillain-Barre syndrome (GBS) is the commonest cause of acute polyradiculoneuropathy that requires hospitalization. Many of these patients experience systemic and disease-related complications during its course. Notable among them is hyponatremia. Though recognized for decades, the precise incidence, prevalence, and mechanism of hyponatremia in GBS are not well known. Hyponatremia in GBS patients is associated with more severe in-hospital disease course, prolonged hospitalization, higher mortality, increased costs, and a greater number of other complications in the hospital and worse functional status at 6 months and at 1 year. Though there are several reports of low sodium associated with GBS, many have not included the exact temporal relationship of sodium or its serial values during GBS thereby underestimating the exact incidence, prevalence, and magnitude of the problem. Early detection, close monitoring, and better understanding of the pathophysiology of hyponatremia have therapeutic implications. We review the complexities of the relationship between hyponatremia and GBS with regard to its pathophysiology and treatment.

3.
Eur Respir J ; 61(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36229049

RESUMO

BACKGROUND: Identifying risk factors for poor outcomes can help with risk stratification and targeting of treatment. Risk factors for mortality and exacerbations have been identified in bronchiectasis but have been almost exclusively studied in European and North American populations. This study investigated the risk factors for poor outcome in a large population of bronchiectasis patients enrolled in India. METHODS: The European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) and Respiratory Research Network of India (EMBARC-India) registry is a prospective observational study of adults with computed tomography-confirmed bronchiectasis enrolled at 31 sites across India. Baseline characteristics of patients were used to investigate associations with key clinical outcomes: mortality, severe exacerbations requiring hospital admission, overall exacerbation frequency and decline in forced expiratory volume in 1 s. RESULTS: 1018 patients with at least 12-month follow-up data were enrolled in the follow-up study. Frequent exacerbations (≥3 per year) at baseline were associated with an increased risk of mortality (hazard ratio (HR) 3.23, 95% CI 1.39-7.50), severe exacerbations (HR 2.71, 95% CI 1.92-3.83), future exacerbations (incidence rate ratio (IRR) 3.08, 95% CI 2.36-4.01) and lung function decline. Coexisting COPD, dyspnoea and current cigarette smoking were similarly associated with a worse outcome across all end-points studied. Additional predictors of mortality and severe exacerbations were increasing age and cardiovascular comorbidity. Infection with Gram-negative pathogens (predominantly Klebsiella pneumoniae) was independently associated with increased mortality (HR 3.13, 95% CI 1.62-6.06), while Pseudomonas aeruginosa infection was associated with severe exacerbations (HR 1.41, 95% CI 1.01-1.97) and overall exacerbation rate (IRR 1.47, 95% CI 1.13-1.91). CONCLUSIONS: This study identifies risk factors for morbidity and mortality among bronchiectasis patients in India. Identification of these risk factors may support treatment approaches optimised to an Asian setting.


Assuntos
Bronquiectasia , Adulto , Humanos , Seguimentos , Bronquiectasia/terapia , Bronquiectasia/tratamento farmacológico , Pulmão , Sistema de Registros , Progressão da Doença
4.
Nanotechnology ; 34(44)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37527631

RESUMO

We report the formation of Mo1-xWxO3-CdS (0 ≤ x ≤1) nanophotocatalysts by a combination of solid-state and solution-impregnation processes. The formation of 2D+1D heterostructured composite was revealed by electron microscopy and the structure of ternary co-catalyst and photocatalysts were confirmed by spectroscopic analyses. The H2evolution activity of the nanocomposites was assessed via photocatalytic splitting of water under the irradiation of visible light. All the nanocomposites studied here exhibit notable catalytic activity and good photostability using lactic acid as the sacrificial electron donor compared to a pristine compound. Among these nanocomposites, WO3-CdS shows superior activity with H2evolution rates of 15.19 mmolg-1h-1, 28 times higher than the pure CdS. The WO3-CdS photoactivity is not only superior among all the composites studied here but also highest among the reported WO3composite catalysts to date. The novel construction of the oxide-based nanocomposite photocatalyst shown here efficiently enhances the catalytic activity by effective separation of charge carriers and inhibits photocorrosion of CdS nanorods. The apparent quantum yield of the hydrogen evolution for WO3-CdS was found to be 8% in the visible spectral range. The disparity of the catalytic ability between MoO3and WO3and the variance among the compositions was unraveled through optical band-offset alignment with respect to CdS. Though the 2D+1D novel fabrication is common to all the composites, the difference in the type of band alignment MoO3(type-I) and WO3(type-II) with CdS plays a highly significant role in the co-catalytic activity.

5.
PLoS Genet ; 15(10): e1008460, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31671093

RESUMO

Malfunction of pre-mRNA processing factors are linked to several human diseases including cancer and neurodegeneration. Here we report the identification of a de novo heterozygous missense mutation in the SNRPE gene (c.65T>C (p.Phe22Ser)) in a patient with non-syndromal primary (congenital) microcephaly and intellectual disability. SNRPE encodes SmE, a basal component of pre-mRNA processing U snRNPs. We show that the microcephaly-linked SmE variant is unable to interact with the SMN complex and as a consequence fails to assemble into U snRNPs. This results in widespread mRNA splicing alterations in fibroblast cells derived from this patient. Similar alterations were observed in HEK293 cells upon SmE depletion that could be rescued by the expression of wild type but not mutant SmE. Importantly, the depletion of SmE in zebrafish causes aberrant mRNA splicing alterations and reduced brain size, reminiscent of the patient microcephaly phenotype. We identify the EMX2 mRNA, which encodes a protein required for proper brain development, as a major mis-spliced down stream target. Together, our study links defects in the SNRPE gene to microcephaly and suggests that alterations of cellular splicing of specific mRNAs such as EMX2 results in the neurological phenotype of the disease.


Assuntos
Processamento Alternativo , Proteínas de Homeodomínio/genética , Deficiência Intelectual/genética , Microcefalia/genética , Mutação de Sentido Incorreto , Fatores de Transcrição/genética , Proteínas Centrais de snRNP/genética , Animais , Linhagem Celular , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Linhagem , Splicing de RNA , RNA Mensageiro/genética , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Sequenciamento do Exoma , Peixe-Zebra , Proteínas Centrais de snRNP/química , Proteínas Centrais de snRNP/metabolismo
6.
Acta Virol ; 66(3): 249-253, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36029089

RESUMO

Defensins, crucial components of the innate immune system, play a vital role against infection as part of frontline immunity. Association of SARS-CoV-2 infection with defensins has not been investigated. In this study, we have investigated the expression of defensin genes in the buccal cavity from patients with COVID-19 infection along with negative control samples. Nasopharyngeal/oropharyngeal swab samples collected for screening SARS-CoV-2 infection in early 2020 from Hyderabad, India, were analyzed for the expression of major defensin genes by the quantitative real-time reverse transcription polymerase chain reaction, qRT-PCR. Forty SARS-CoV-2 infected positive and 40 negative swab samples were selected for this study. Based on the qRT-PCR analysis involving gene specific primers for defensin genes, 9 defensin genes were found to be expressed in the nasopharyngeal/oropharyngeal cavity. Four defensin genes were found to be significantly down regulated in SARS-CoV-2 infected patients in comparison with the control samples based on differential expression analysis. The significantly down regulated genes were defensin beta 4A/B, 106B, 107B, and 103A. Down regulation of human beta defensin 2, 3, 6 and 7 suggests that antiviral innate immune response provided by defensins may be compromised in SARS-CoV-2 infection resulting in progression of the disease. Correction of the down regulation process through appropriate defensin peptide-based therapy could be an attractive method of treatment. Keywords: host defense; defensins; COVID-19; gene regulation; SARS-CoV-2.


Assuntos
COVID-19 , beta-Defensinas , Antivirais , COVID-19/genética , Regulação para Baixo , Humanos , SARS-CoV-2/genética , beta-Defensinas/genética
7.
N Engl J Med ; 379(8): 743-752, 2018 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-29949473

RESUMO

BACKGROUND: Postpartum hemorrhage is the most common cause of maternal death. Oxytocin is the standard therapy for the prevention of postpartum hemorrhage, but it requires cold storage, which is not available in many countries. In a large trial, we compared a novel formulation of heat-stable carbetocin with oxytocin. METHODS: We enrolled women across 23 sites in 10 countries in a randomized, double-blind, noninferiority trial comparing intramuscular injections of heat-stable carbetocin (at a dose of 100 µg) with oxytocin (at a dose of 10 IU) administered immediately after vaginal birth. Both drugs were kept in cold storage (2 to 8°C) to maintain double-blinding. There were two primary outcomes: the proportion of women with blood loss of at least 500 ml or the use of additional uterotonic agents, and the proportion of women with blood loss of at least 1000 ml. The noninferiority margins for the relative risks of these outcomes were 1.16 and 1.23, respectively. RESULTS: A total of 29,645 women underwent randomization. The frequency of blood loss of at least 500 ml or the use of additional uterotonic agents was 14.5% in the carbetocin group and 14.4% in the oxytocin group (relative risk, 1.01; 95% confidence interval [CI], 0.95 to 1.06), a finding that was consistent with noninferiority. The frequency of blood loss of at least 1000 ml was 1.51% in the carbetocin group and 1.45% in the oxytocin group (relative risk, 1.04; 95% CI, 0.87 to 1.25), with the confidence interval crossing the margin of noninferiority. The use of additional uterotonic agents, interventions to stop bleeding, and adverse effects did not differ significantly between the two groups. CONCLUSIONS: Heat-stable carbetocin was noninferior to oxytocin for the prevention of blood loss of at least 500 ml or the use of additional uterotonic agents. Noninferiority was not shown for the outcome of blood loss of at least 1000 ml; low event rates for this outcome reduced the power of the trial. (Funded by Merck Sharpe & Dohme; CHAMPION Australian New Zealand Clinical Trials Registry number, ACTRN12614000870651 ; EudraCT number, 2014-004445-26 ; and Clinical Trials Registry-India number, CTRI/2016/05/006969 .).


Assuntos
Ocitócicos/uso terapêutico , Ocitocina/análogos & derivados , Ocitocina/uso terapêutico , Hemorragia Pós-Parto/prevenção & controle , Adulto , Método Duplo-Cego , Estabilidade de Medicamentos , Feminino , Humanos , Injeções Intramusculares , Ocitócicos/efeitos adversos , Ocitocina/efeitos adversos , Gravidez , Risco , Adulto Jovem
8.
Reprod Health ; 17(Suppl 2): 154, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256770

RESUMO

BACKGROUND: While the relationship between hemoglobin (Hb) concentrations and pregnancy outcomes has been studied often, most reports have focused on a specific Hb cutoff used to define anemia. Fewer studies have evaluated pregnancy outcomes across the entire range of Hb values. Moreover, to date, most studies of the relationship of Hb concentrations to pregnancy outcomes have been done in high-income countries. Thus, we have sought to determine the relationship between the range of maternal Hb concentrations and adverse birth outcomes among South Asian pregnant women. METHODS: For this study, we used data collected from two South Asian countries (Pakistan - Sindh Province and two sites in India - Belagavi and Nagpur) in a prospective maternal and newborn health registry study. To assess the association between Hb concentrations and various maternal and fetal outcomes, we classified the Hb concentrations into seven categories. Regression analyses adjusting for multiple potential confounders were performed to assess adverse pregnancy outcomes across the range of Hb concentrations. FINDINGS: Between January 2012 and December 2018, 130,888 pregnant women were enrolled in the South Asian sites had a Hb measurement available, delivered and were included in the analyses. Overall, the mean Hb concentration of pregnant women from the sites was 9.9 g/dL, 10.0 g/dL in the Indian sites and 9.5 g/dL in the Pakistan site. Hb concentrations < 7 g/dL were observed in 6.9% of the pregnant Pakistani women and 0.2% of the Indian women. In both the Pakistani and Indian sites, women with higher parity and women with no formal education had lower Hb concentrations. In the Pakistani site, women > 35 years of age, women with ≥4 children and those who enrolled in the third trimester were more likely to have Hb concentrations of < 7 g/dL but these associations were not found for the Indian sites. When adjusting for potential confounders, for both India and Pakistan, lower Hb concentrations were associated with stillbirth, preterm birth, lower mean birthweight, and increased risk of low birthweight. In the Pakistani site, there was evidence of a U-shaped relationship between Hb concentrations and low birth weight, and neonatal mortality, and in India with hypertensive disease. INTERPRETATION: This study documented the relationship between maternal Hb concentrations and adverse pregnancy outcomes in women from the Pakistani and Indian sites across the range of Hb values. Both low and high Hb concentrations were associated with risk of at least some adverse outcomes. Hence, both low and high values of Hb should be considered risk factors for the mother and fetus.


Assuntos
Hemoglobinas/metabolismo , Saúde do Lactente , Mortalidade Infantil , Complicações Hematológicas na Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Natimorto/epidemiologia , Adulto , Anemia/epidemiologia , Criança , Feminino , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Paquistão/epidemiologia , Gravidez , Resultado da Gravidez/epidemiologia , Gestantes , Nascimento Prematuro/sangue , Nascimento Prematuro/etiologia , Estudos Prospectivos , Sistema de Registros
9.
Reprod Health ; 17(Suppl 3): 193, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334359

RESUMO

BACKGROUND: Socioeconomic status (SES) is an important determinant of health globally and an important explanatory variable to assess causality in epidemiological research. The 10th Sustainable Development Goal is to reduce disparities in SES that impact health outcomes globally. It is easier to study SES in high-income countries because household income is representative of the SES. However, it is well recognized that income is poorly reported in low- and middle- income countries (LMIC) and is an unreliable indicator of SES. Therefore, there is a need for a robust index that will help to discriminate the SES of rural households in a pooled dataset from LMIC. METHODS: The study was nested in the population-based Maternal and Neonatal Health Registry of the Global Network for Women's and Children's Health Research which has 7 rural sites in 6 Asian, sub-Saharan African and Central American countries. Pregnant women enrolling in the Registry were asked questions about items such as housing conditions and household assets. The characteristics of the candidate items were evaluated using confirmatory factor analyses and item response theory analyses. Based on the results of these analyses, a final set of items were selected for the SES index. RESULTS: Using data from 49,536 households of pregnant women, we reduced the data collected to a 10-item index. The 10 items were feasible to administer, covered the SES continuum and had good internal reliability and validity. We developed a sum score-based Item Response Theory scoring algorithm which is easy to compute and is highly correlated with scores based on response patterns (r = 0.97), suggesting minimal loss of information with the simplified approach. Scores varied significantly by site (p < 0.001). African sites had lower mean SES scores than the Asian and Central American sites. The SES index demonstrated good internal consistency reliability (Cronbach's alpha = 0.81). Higher SES scores were significantly associated with formal education, more education, having received antenatal care, and facility delivery (p < 0.001). CONCLUSIONS: While measuring SES in LMIC is challenging, we have developed a Global Network Socioeconomic Status Index which may be useful for comparisons of SES within and between locations. Next steps include understanding how the index is associated with maternal, perinatal and neonatal mortality. Trial Registration NCT01073475 Socioeconomic status (SES) is an important determinant of health globally, and improving SES is important to reduce disparities in health outcomes. It is easier to study SES in high-income countries because it can be measured by income and what income is spent on, but this concept does not translate easily to low and middle income countries. We developed a questionnaire that includes 10 items to determine SES in low-resource settings that was added to an ongoing Maternal and Neonatal Health Registry that is funded by the National Institutes of Child Health and Human Development's Global Network. The Registry includes sites that collect outcomes of pregnancies in women and their babies in rural areas in 6 countries in South Asia, sub-Saharan Africa and Central America. The Registry is population based and tracks women from early in pregnancy to day 42 post-partum. The questionnaire is easy to administer and has good reliability and validity. Next steps include understanding how the index is associated with maternal, fetal and neonatal mortality.


Assuntos
Saúde da Criança , Saúde Materna , Classe Social , Determinantes Sociais da Saúde , Criança , Países em Desenvolvimento , Feminino , Saúde Global , Disparidades em Assistência à Saúde , Humanos , Recém-Nascido , Gravidez , Reprodutibilidade dos Testes , Inquéritos e Questionários
10.
Reprod Health ; 17(Suppl 3): 182, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334362

RESUMO

BACKGROUND: Nulliparity has been associated with lower birth weight (BW) and other adverse pregnancy outcomes, with most of the data coming from high-income countries. In this study, we examined birth weight for gestational age z-scores and neonatal (28-day) mortality in a large prospective cohort of women dated by first trimester ultrasound from multiple sites in low and middle-income countries. METHODS: Pregnant women were recruited during the first trimester of pregnancy and followed through 6 weeks postpartum from Maternal Newborn Health Registry (MNHR) sites in the Democratic Republic of Congo (DRC), Guatemala, Belagavi and Nagpur, India, and Pakistan from 2017 and 2018. Data related to the pregnancy and its outcomes were collected prospectively. First trimester ultrasound was used for determination of gestational age; (BW) was obtained in grams within 48 h of delivery and later transformed to weight for age z-scores (WAZ) adjusted for gestational age using the INTERGROWTH-21st standards. RESULTS: 15,121 women were eligible and included. Infants of nulliparous women had lower mean BWs (males: 2676 gr, females: 2587 gr, total: 2634 gr) and gestational age adjusted weight for age z-scores (males: - 0.73, females: - 0.77, total: - 0.75,) than women with one or more previous pregnancies. The largest differences were between zero and one previous pregnancies among female infants. The associations of parity with BW and z-scores remained even after adjustment for maternal age, maternal height, maternal education, antenatal care visits, hypertensive disorders, and socioeconomic status. Nulliparous women also had a significantly higher < 28-day neonatal mortality rate (27.7 per 1,000 live births) than parous women (17.2 and 20.7 for parity of 1-3 and ≥ 4 respectively). Risk of preterm birth was higher among women with ≥ 4 previous pregnancies (15.5%) compared to 11.3% for the nulliparous group and 11.8% for women with one to three previous pregnancies (p = 0.0072). CONCLUSIONS: In this large sample from diverse settings, nulliparity was independently associated with both lower BW and WAZ scores as well as higher neonatal mortality compared to multiparity.


Assuntos
Peso ao Nascer , Paridade , Morte Perinatal , Nascimento Prematuro , Feminino , Humanos , Lactente , Saúde do Lactente , Recém-Nascido , Masculino , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Sistema de Registros
11.
Reprod Health ; 17(Suppl 3): 165, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334352

RESUMO

BACKGROUND: The objectives of this analysis were to document trends in and risk factors associated with the cesarean birth rate in low- and middle-income country sites participating in the Global Network for Women's and Children's Health Research (Global Network). METHODS: This is a secondary analysis of a prospective, population-based study of home and facility births conducted in the Global Network sites. RESULTS: Cesarean birth rates increased uniformly across all sites between 2010 and 2018. Across all sites in multivariable analyses, women younger than age twenty had a reduced risk of cesarean birth (RR 0.9 [0.9, 0.9]) and women over 35 had an increased risk of cesarean birth (RR 1.1 [1.1, 1.1]) compared to women aged 20 to 35. Compared to women with a parity of three or more, less parous women had an increased risk of cesarean (RR 1.2 or greater [1.2, 1.4]). Four or more antenatal visits (RR 1.2 [1.2, 1.3]), multiple pregnancy (RR 1.3 [1.3, 1.4]), abnormal progress in labor (RR 1.1 [1.0, 1.1]), antepartum hemorrhage (RR 2.3 [2.0, 2.7]), and hypertensive disease (RR 1.6 [1.5, 1.7]) were all associated with an increased risk of cesarean birth, p < 0.001. For multiparous women with a history of prior cesarean birth, rates of vaginal birth after cesarean were about 20% in the Latin American and Southeast Asian sites and about 84% at the sub-Saharan African sites. In the African sites, proportions of cesarean birth in the study were highest among women without a prior cesarean and a single, cephalic, term pregnancy. In the non-African sites, groups with the greatest proportion of cesarean births were nulliparous women with a single, cephalic, term pregnancy and all multiparous women with at least one previous uterine scar with a term, cephalic pregnancy. CONCLUSION: Cesarean birth rates continue to rise within the Global Network. The proportions of cesarean birth are higher among women with no history of cesarean birth in the African sites and among women with primary elective cesarean, primary cesarean after induction, and repeat cesarean in the non-African sites.


Assuntos
Coeficiente de Natalidade , Cesárea/estatística & dados numéricos , Cesárea/tendências , Saúde da Criança , Nascimento Vaginal Após Cesárea/estatística & dados numéricos , Adulto , Cesárea/efeitos adversos , Criança , Feminino , Humanos , Recém-Nascido , Paridade , Vigilância da População , Gravidez , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
12.
Reprod Health ; 17(Suppl 3): 187, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334356

RESUMO

BACKGROUND: Preterm birth continues to be a major public health problem contributing to 75% of the neonatal mortality worldwide. Low birth weight (LBW) is an important but imperfect surrogate for prematurity when accurate assessment of gestational age is not possible. While there is overlap between preterm birth and LBW newborns, those that are both premature and LBW are at the highest risk of adverse neonatal outcomes. Understanding the epidemiology of preterm birth and LBW is important for prevention and improved care for at risk newborns, but in many countries, data are sparse and incomplete. METHODS: We conducted data analyses using the Global Network's (GN) population-based registry of pregnant women and their babies in rural communities in six low- and middle-income countries (Democratic Republic of Congo, Kenya, Zambia, Guatemala, India and Pakistan). We analyzed data from January 2014 to December 2018. Trained study staff enrolled all pregnant women in the study catchment area as early as possible during pregnancy and conducted follow-up visits shortly after delivery and at 42 days after delivery. We analyzed the rates of preterm birth, LBW and the combination of preterm birth and LBW and studied risk factors associated with these outcomes across the GN sites. RESULTS: A total of 272,192 live births were included in the analysis. The overall preterm birth rate was 12.6% (ranging from 8.6% in Belagavi, India to 21.8% in the Pakistani site). The overall LBW rate was 13.6% (ranging from 2.7% in the Kenyan site to 21.4% in the Pakistani site). The overall rate of both preterm birth and LBW was 5.5% (ranging from 1.2% in the Kenyan site to 11.0% in the Pakistani site). Risk factors associated with preterm birth, LBW and the combination were similar across sites and included nulliparity [RR - 1.27 (95% CI 1.21-1.33)], maternal age under 20 [RR 1.41 (95% CI 1.32-1.49)] years, severe antenatal hemorrhage [RR 5.18 95% CI 4.44-6.04)], hypertensive disorders [RR 2.74 (95% CI - 1.21-1.33], and 1-3 antenatal visits versus four or more [RR 1.68 (95% CI 1.55-1.83)]. CONCLUSIONS: Preterm birth, LBW and their combination continue to be common public health problems at some of the GN sites, particularly among young, nulliparous women who have received limited antenatal care services. Trial registration The identifier of the Maternal and Newborn Health Registry at ClinicalTrials.gov is NCT01073475. TRIAL REGISTRATION: The identifier of the Maternal and Newborn Health Registry at ClinicalTrials.gov is NCT01073475.


Assuntos
Recém-Nascido de Baixo Peso , Nascimento Prematuro/epidemiologia , Peso ao Nascer , Países em Desenvolvimento , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Fatores de Risco
13.
Reprod Health ; 17(Suppl 3): 176, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334365

RESUMO

BACKGROUND: Birth weight (BW) is a strong predictor of neonatal outcomes. The purpose of this study was to compare BWs between global regions (south Asia, sub-Saharan Africa, Central America) prospectively and to determine if trends exist in BW over time using the population-based maternal and newborn registry (MNHR) of the Global Network for Women'sand Children's Health Research (Global Network). METHODS: The MNHR is a prospective observational population-based registryof six research sites participating in the Global Network (2013-2018), within five low- and middle-income countries (Kenya, Zambia, India, Pakistan, and Guatemala) in threeglobal regions (sub-Saharan Af rica, south Asia, Central America). The birth weights were obtained for all infants born during the study period. This was done either by abstracting from the infants' health facility records or from direct measurement by the registry staff for infants born at home. After controlling for demographic characteristics, mixed-effect regression models were utilized to examine regional differences in birth weights over time. RESULTS: The overall BW meanswere higher for the African sites (Zambia and Kenya), 3186 g (SD 463 g) in 2013 and 3149 g (SD 449 g) in 2018, ascompared to Asian sites (Belagavi and Nagpur, India and Pakistan), 2717 g (SD450 g) in 2013 and 2713 g (SD 452 g) in 2018. The Central American site (Guatemala) had a mean BW intermediate between the African and south Asian sites, 2928 g (SD 452) in 2013, and 2874 g (SD 448) in 2018. The low birth weight (LBW) incidence was highest in the south Asian sites (India and Pakistan) and lowest in the African sites (Kenya and Zambia). The size of regional differences varied somewhat over time with slight decreases in the gap in birth weights between the African and Asian sites and slight increases in the gap between the African and Central American sites. CONCLUSIONS: Overall, BWmeans by global region did not change significantly over the 5-year study period. From 2013 to 2018, infants enrolled at the African sites demonstrated the highest BW means overall across the entire study period, particularly as compared to Asian sites. The incidence of LBW was highest in the Asian sites (India and Pakistan) compared to the African and Central American sites. Trial registration The study is registered at clinicaltrials.gov. ClinicalTrial.gov Trial Registration: NCT01073475.


Assuntos
Peso ao Nascer , Países em Desenvolvimento , Mortalidade Infantil/tendências , África , Ásia , América Central , Criança , Estudos de Coortes , Feminino , Saúde Global , Humanos , Lactente , Mortalidade Infantil/etnologia , Recém-Nascido de Baixo Peso , Recém-Nascido , Estudos Longitudinais , Masculino , Estudos Prospectivos
14.
Reprod Health ; 17(Suppl 2): 146, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256783

RESUMO

BACKGROUND: Stillbirth rates are high and represent a substantial proportion of the under-5 mortality in low and middle-income countries (LMIC). In LMIC, where nearly 98% of stillbirths worldwide occur, few population-based studies have documented cause of stillbirths or the trends in rate of stillbirth over time. METHODS: We undertook a prospective, population-based multi-country research study of all pregnant women in defined geographic areas across 7 sites in low-resource settings (Kenya, Zambia, Democratic Republic of Congo, India, Pakistan, and Guatemala). Staff collected demographic and health care characteristics with outcomes obtained at delivery. Cause of stillbirth was assigned by algorithm. RESULTS: From 2010 through 2018, 573,148 women were enrolled with delivery data obtained. Of the 552,547 births that reached 500 g or 20 weeks gestation, 15,604 were stillbirths; a rate of 28.2 stillbirths per 1000 births. The stillbirth rates were 19.3 in the Guatemala site, 23.8 in the African sites, and 33.3 in the Asian sites. Specifically, stillbirth rates were highest in the Pakistan site, which also documented a substantial decrease in stillbirth rates over the study period, from 56.0 per 1000 (95% CI 51.0, 61.0) in 2010 to 44.4 per 1000 (95% CI 39.1, 49.7) in 2018. The Nagpur, India site also documented a substantial decrease in stillbirths from 32.5 (95% CI 29.0, 36.1) to 16.9 (95% CI 13.9, 19.9) per 1000 in 2018; however, other sites had only small declines in stillbirth over the same period. Women who were less educated and older as well as those with less access to antenatal care and with vaginal assisted delivery were at increased risk of stillbirth. The major fetal causes of stillbirth were birth asphyxia (44.0% of stillbirths) and infectious causes (22.2%). The maternal conditions that were observed among those with stillbirth were obstructed or prolonged labor, antepartum hemorrhage and maternal infections. CONCLUSIONS: Over the study period, stillbirth rates have remained relatively high across all sites. With the exceptions of the Pakistan and Nagpur sites, Global Network sites did not observe substantial changes in their stillbirth rates. Women who were less educated and had less access to antenatal and obstetric care remained at the highest burden of stillbirth. STUDY REGISTRATION: Clinicaltrials.gov (ID# NCT01073475).


Assuntos
Parto Obstétrico , Países em Desenvolvimento , Complicações do Trabalho de Parto , Natimorto/epidemiologia , Feminino , Guatemala/epidemiologia , Humanos , Índia , Recém-Nascido , Quênia , Masculino , Paquistão/epidemiologia , Vigilância da População , Gravidez , Estudos Prospectivos , Zâmbia/epidemiologia
15.
Reprod Health ; 17(Suppl 2): 157, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256784

RESUMO

BACKGROUND: Due to high fertility rates in some low and lower-middle income countries, the interval between pregnancies can be short, which may lead to adverse maternal and neonatal outcomes. METHODS: We analyzed data from women enrolled in the NICHD Global Network Maternal Newborn Health Registry (MNHR) from 2013 through 2018. We report maternal characteristics and outcomes in relationship to the inter-delivery interval (IDI, time from previous delivery [live or stillborn] to the delivery of the index birth), by category of 6-17 months (short), 18-36 months (reference), 37-60 months, and 61-180 months (long). We used non-parametric tests for maternal characteristics, and multivariable logistic regression models for outcomes, controlling for differences in baseline characteristics. RESULTS: We evaluated 181,782 women from sites in the Democratic Republic of Congo, Zambia, Kenya, Guatemala, India, and Pakistan. Women with short IDI varied by site, from 3% in the Zambia site to 20% in the Pakistan site. Relative to a 18-36 month IDI, women with short IDI had increased risk of neonatal death (RR = 1.89 [1.74, 2.05]), stillbirth (RR = 1.70 [1.56, 1.86]), low birth weight (RR = 1.38 [1.32, 1.44]), and very low birth weight (RR = 2.35 [2.10, 2.62]). Relative to a 18-36 month IDI, women with IDI of 37-60 months had an increased risk of maternal death (RR 1.40 [1.05, 1.88]), stillbirth (RR 1.14 [1.08, 1.22]), and very low birth weight (RR 1.10 [1.01, 1.21]). Relative to a 18-36 month IDI, women with long IDI had increased risk of maternal death (RR 1.54 [1.10, 2.16]), neonatal death (RR = 1.25 [1.14, 1.38]), stillbirth (RR = 1.50 [1.38, 1.62]), low birth weight (RR = 1.22 [1.17, 1.27]), and very low birth weight (RR = 1.47 [1.32,1.64]). Short and long IDIs were also associated with increased risk of obstructed labor, hemorrhage, hypertensive disorders, fetal malposition, infection, hospitalization, preterm delivery, and neonatal hospitalization. CONCLUSIONS: IDI varies by site. When compared to 18-36 month IDI, women with both short IDI and long IDI had increased risk of adverse maternal and neonatal outcomes. TRIAL REGISTRATION: The MNHR is registered at NCT01073475 .


Assuntos
Intervalo entre Nascimentos , Parto Obstétrico/estatística & dados numéricos , Mortalidade Infantil , Morte Materna/etiologia , Mortalidade Materna , Resultado da Gravidez/epidemiologia , Adulto , Parto Obstétrico/métodos , Países em Desenvolvimento , Feminino , Humanos , Lactente , Mortalidade Infantil/tendências , Recém-Nascido de Baixo Peso , Recém-Nascido , Mortalidade Materna/etnologia , Mortalidade Materna/tendências , Vigilância da População , Gravidez
16.
Reprod Health ; 17(Suppl 2): 156, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256790

RESUMO

BACKGROUND: Neonatal deaths in first 28-days of life represent 47% of all deaths under the age of five years globally and are a focus of the United Nation's (UN's) Sustainable Development Goals. Pregnant women are delivering in facilities but that does not indicate quality of care during delivery and the postpartum period. The World Health Organization's Essential Newborn Care (ENC) package reduces neonatal mortality, but lacks a simple and valid composite index that measures its effectiveness. METHODS: Data on 5 intra-partum and 3 post-partum practices (indicators) recommended as part of ENC, routinely collected in NICHD's Global Network's (GN) Maternal Newborn Health Registry (MNHR) between 2010 and 2013, were included. We evaluated if all 8 practices (Care around Delivery - CAD), combined as an index was associated with reduced early neonatal mortality rates (days 0-6 of life). RESULTS: A total of 150,848 live births were included in the analysis. The individual indicators varied across sites. All components were present in 19.9% births (range 0.4 to 31% across sites). Present indicators (8 components) were associated with reduced early neonatal mortality [adjusted RR (95% CI):0.81 (0.77, 0.85); p < 0.0001]. Despite an overall association between CAD and early neonatal mortality (RR < 1.0 for all early mortality): delivery by skilled birth attendant; presence of fetal heart and delayed bathing were associated with increased early neonatal mortality. CONCLUSIONS: Present indicators (8 practices) of CAD were associated with a 19% reduction in the risk of neonatal death in the diverse health facilities where delivery occurred within the GN MNHR. These indicators could be monitored to identify facilities that need to improve compliance with ENC practices to reduce preventable neonatal deaths. Three of the 8 indicators were associated with increased neonatal mortality, due to baby being sick at birth. Although promising, this composite index needs refinement before use to monitor facility-based quality of care in association with early neonatal mortality. Trial registration The identifier of the Maternal Newborn Health Registry at ClinicalTrials.gov is NCT01073475.


Assuntos
Saúde do Lactente , Trabalho de Parto , Morte Perinatal , Cuidado Pós-Natal , Cuidado Pré-Natal , Qualidade da Assistência à Saúde , Pré-Escolar , Feminino , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Gravidez , Sistema de Registros
17.
Reprod Health ; 17(Suppl 3): 190, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334329

RESUMO

BACKGROUND: Pakistan has among the poorest pregnancy outcomes worldwide, significantly worse than many other low-resource countries. The reasons for these differences are not clear. In this study, we compared pregnancy outcomes in Pakistan to other low-resource countries and explored factors that might help explain these differences. METHODS: The Global Network (GN) Maternal Newborn Health Registry (MNHR) is a prospective, population-based observational study that includes all pregnant women and their pregnancy outcomes in defined geographic communities in six low-middle income countries (India, Pakistan, Democratic Republic of Congo, Guatemala, Kenya, Zambia). Study staff enroll women in early pregnancy and follow-up soon after delivery and at 42 days to ascertain delivery, neonatal, and maternal outcomes. We analyzed the maternal mortality ratios (MMR), neonatal mortality rates (NMR), stillbirth rates, and potential explanatory factors from 2010 to 2018 across the GN sites. RESULTS: From 2010 to 2018, there were 91,076 births in Pakistan and 456,276 births in the other GN sites combined. The MMR in Pakistan was 319 per 100,000 live births compared to an average of 124 in the other sites, while the Pakistan NMR was 49.4 per 1,000 live births compared to 20.4 in the other sites. The stillbirth rate in Pakistan was 53.5 per 1000 births compared to 23.2 for the other sites. Preterm birth and low birthweight rates were also substantially higher than the other sites combined. Within weight ranges, the Pakistani site generally had significantly higher rates of stillbirth and neonatal mortality than the other sites combined, with differences increasing as birthweights increased. By nearly every measure, medical care for pregnant women and their newborns in the Pakistan sites was worse than at the other sites combined. CONCLUSION: The Pakistani pregnancy outcomes are much worse than those in the other GN sites. Reasons for these poorer outcomes likely include that the Pakistani sites' reproductive-aged women are largely poorly educated, undernourished, anemic, and deliver a high percentage of preterm and low-birthweight babies in settings of often inadequate maternal and newborn care. By addressing the issues highlighted in this paper there appears to be substantial room for improvements in Pakistan's pregnancy outcomes.


Assuntos
Mortalidade Infantil/etnologia , Mortalidade Materna/etnologia , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Natimorto/etnologia , Adulto , Países em Desenvolvimento , Feminino , Humanos , Lactente , Recém-Nascido , Paquistão/epidemiologia , Gravidez , Estudos Prospectivos , Natimorto/epidemiologia
18.
Reprod Health ; 17(Suppl 3): 173, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334343

RESUMO

BACKGROUND: Maternal mortality is a public health problem that disproportionately affects low and lower-middle income countries (LMICs). Appropriate data sources are lacking to effectively track maternal mortality and monitor changes in this health indicator over time. METHODS: We analyzed data from women enrolled in the NICHD Global Network for Women's and Children's Health Research Maternal Newborn Health Registry (MNHR) from 2010 through 2018. Women delivering within research sites in the Democratic Republic of Congo, Guatemala, India (Nagpur and Belagavi), Kenya, Pakistan, and Zambia are included. We evaluated maternal and delivery characteristics using log-binomial models and multivariable models to obtain relative risk estimates for mortality. We used running averages to track maternal mortality ratio (MMR, maternal deaths per 100,000 live births) over time. RESULTS: We evaluated 571,321 pregnancies and 842 maternal deaths. We observed an MMR of 157 / 100,000 live births (95% CI 147, 167) across all sites, with a range of MMRs from 97 (76, 118) in the Guatemala site to 327 (293, 361) in the Pakistan site. When adjusted for maternal risk factors, risks of maternal mortality were higher with maternal age > 35 (RR 1.43 (1.06, 1.92)), no maternal education (RR 3.40 (2.08, 5.55)), lower education (RR 2.46 (1.54, 3.94)), nulliparity (RR 1.24 (1.01, 1.52)) and parity > 2 (RR 1.48 (1.15, 1.89)). Increased risk of maternal mortality was also associated with occurrence of obstructed labor (RR 1.58 (1.14, 2.19)), severe antepartum hemorrhage (RR 2.59 (1.83, 3.66)) and hypertensive disorders (RR 6.87 (5.05, 9.34)). Before and after adjusting for other characteristics, physician attendance at delivery, delivery in hospital and Caesarean delivery were associated with increased risk. We observed variable changes over time in the MMR within sites. CONCLUSIONS: The MNHR is a useful tool for tracking MMRs in these LMICs. We identified maternal and delivery characteristics associated with increased risk of death, some might be confounded by indication. Despite declines in MMR in some sites, all sites had an MMR higher than the Sustainable Development Goals target of below 70 per 100,000 live births by 2030. TRIAL REGISTRATION: The MNHR is registered at NCT01073475 .


Assuntos
Parto Obstétrico/estatística & dados numéricos , Morte Materna/etiologia , Saúde Materna/estatística & dados numéricos , Mortalidade Materna/tendências , Resultado da Gravidez/epidemiologia , Desenvolvimento Sustentável , Criança , Parto Obstétrico/métodos , Países em Desenvolvimento , Feminino , Saúde Global/estatística & dados numéricos , Humanos , Recém-Nascido , Mortalidade Materna/etnologia , Gravidez , Complicações na Gravidez/epidemiologia , Transtornos Puerperais/epidemiologia , Fatores de Risco
19.
Reprod Health ; 17(Suppl 2): 158, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256782

RESUMO

BACKGROUND: Babies born weighing ≥ 2500 g account for more than 80% of the births in most resource-limited locations and for nearly 50% of the 28-day neonatal deaths. In contrast, in high-resource settings, 28-day neonatal mortality among this group represents only a small fraction of the neonatal deaths. Yet mortality risks for birth weight of ≥ 2500 g is limited. Knowledge regarding the factors associated with mortality in these babies will help in identifying interventions that can reduce mortality. METHODS: The Global Network's Maternal Newborn Health Registry (MNHR) is a prospective, population-based observational study that includes all pregnant women and their pregnancy outcomes in defined geographic communities that has been conducted in research sites in six low-middle income countries (India, Pakistan, Democratic Republic of Congo, Guatemala, Kenya and Zambia). Study staff enroll all pregnant women as early as possible during pregnancy and conduct follow-up visits to ascertain delivery and 28-day neonatal outcomes. We analyzed the neonatal mortality rates (NMR) and risk factors for deaths by 28 days among all live-born babies with a birthweight ≥ 2500 g from 2010 to 2018 across the Global Network sites. RESULTS: Babies born in the Global Network sites from 2010 to 2018 with a birthweight ≥ 2500 g accounted for 84.8% of the births and 45.4% of the 28-day neonatal deaths. Among this group, the overall NMR was 13.1/1000 live births. The overall 28-day NMR for ongoing clusters was highest in Pakistan (29.7/1000 live births) and lowest in the Zambian/Kenyan sites (9.3/1000) for ≥ 2500 g infants. ≥ 2500 g NMRs declined for Zambia/Kenya and India. For Pakistan and Guatemala, the NMR remained almost unchanged over the period. The ≥ 2500 g risks related to maternal, delivery and newborn characteristics varied by site. Maternal factors that increased risk and were common for all sites included nulliparity, hypertensive disease, previous stillbirth, maternal death, obstructed labor, severe postpartum hemorrhage, and abnormal fetal presentation. Neonatal characteristics including resuscitation, hospitalization, congenital anomalies and male sex, as well as lower gestational ages and birthweights were also associated with increased mortality. CONCLUSIONS: Nearly half of neonatal deaths in the Global Network sites occurred in infants born weighing ≥ 2500 g. The NMR for those infants was 13.1 per 1000 live births, much higher than rates usually seen in high-income countries. The changes in NMR over time varied across the sites. Even among babies born ≥ 2500 g, lower gestational age and birthweight were largely associated with increased risk of mortality. Since many of these deaths should be preventable, attention to preventing mortality in these infants should have an important impact on overall NMR. TRIAL REGISTRATION: https://ClinicalTrials.gov Identifier: NCT01073475.


Assuntos
Países em Desenvolvimento , Mortalidade Infantil , Recém-Nascido de Baixo Peso , Morte Perinatal , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Estudos Prospectivos
20.
Mol Cell ; 42(3): 330-41, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21549310

RESUMO

The Polycomb repressive complex 2 (PRC2) confers transcriptional repression through histone H3 lysine 27 trimethylation (H3K27me3). Here, we examined how PRC2 is modulated by histone modifications associated with transcriptionally active chromatin. We provide the molecular basis of histone H3 N terminus recognition by the PRC2 Nurf55-Su(z)12 submodule. Binding of H3 is lost if lysine 4 in H3 is trimethylated. We find that H3K4me3 inhibits PRC2 activity in an allosteric fashion assisted by the Su(z)12 C terminus. In addition to H3K4me3, PRC2 is inhibited by H3K36me2/3 (i.e., both H3K36me2 and H3K36me3). Direct PRC2 inhibition by H3K4me3 and H3K36me2/3 active marks is conserved in humans, mouse, and fly, rendering transcriptionally active chromatin refractory to PRC2 H3K27 trimethylation. While inhibition is present in plant PRC2, it can be modulated through exchange of the Su(z)12 subunit. Inhibition by active chromatin marks, coupled to stimulation by transcriptionally repressive H3K27me3, enables PRC2 to autonomously template repressive H3K27me3 without overwriting active chromatin domains.


Assuntos
Cromatina/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Animais , Western Blotting , Linhagem Celular , Cromatina/genética , Cristalografia por Raios X , Drosophila , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/química , Humanos , Lisina/química , Metilação , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Complexo Repressor Polycomb 2 , Proteínas do Grupo Polycomb , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Repressoras/química , Proteínas Repressoras/genética , Proteína 4 de Ligação ao Retinoblastoma/química , Proteína 4 de Ligação ao Retinoblastoma/genética , Proteína 4 de Ligação ao Retinoblastoma/metabolismo , Transcrição Gênica
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