42 research outputs found
“Dos modelos para evaluar los efectos de la cercanía de la luna sobre la frecuencia de nacimientos. Estudio en población mexicana”.
Desde épocas antiguas la luna es relacionada con la fertilidad. Diversos estudios
intentaron asociar al astro y la frecuencia de los nacimientos, sin obtener
resultados concluyentes. En otras especies animales la influencia que ejerce este
satélite es clara y significativa.
Objetivo. Establecer la relación luna - nacimientos mediante dos modelos
analíticos.
Estudio ambilectivo, observacional y descriptivo, utilizando 25,152 registros de
nacimientos (enero 2009 - junio 2013). El modelo clásico realiza comparativas de
nacimientos entre los periodos lunares (prueba T-Student y ANOVA). El segundo
modelo afronta la cercanía de la luna mediante el porcentaje de luminosidad (eje
X) y la frecuencia de nacimientos (eje Y). El punto de inflexión de la curva fue
calculado mediante la fórmula x = [ln (1/ ebx)]/ ebx.
Resultados. Se estudiaron 25,152 nacimientos. La edad gestacional promedio fue
38.96 semanas. Media de nacimientos: 93.9. Con el nuevo modelo se obtuvo una
estimación curvilínea de concavidad hacia abajo y de crecimiento (p = 0.000*, 95%
IC). El punto medio de inflexión de la curva fue 41.52%, los puntos de inflexión
laterales fueron al 5% y 96%. La función polinómica de la curva fue y = 0.06x2 –
6.33x + 199.18, para la función de crecimiento fue y = 82.02 ·1x
Discusión y conclusiones. Como en otros ensayos, el modelo clásico aportó
resultados poco significativos; sin embargo, el segundo modelo muestra evidencia
que el perigeo lunar (luminosidad 0-5% y 96-100%), genera una influencia positiva
sobre el número de nacimientos, probablemente resultado del efecto Tidal. En
productos prematuros el incremento sólo se observa durante luna llena (p=0.056-
,95% IC)
Identification, Replication, and Functional Fine-Mapping of Expression Quantitative Trait Loci in Primary Human Liver Tissue
The discovery of expression quantitative trait loci (“eQTLs”) can
help to unravel genetic contributions to complex traits. We identified genetic
determinants of human liver gene expression variation using two independent
collections of primary tissue profiled with Agilent
(n = 206) and Illumina (n = 60)
expression arrays and Illumina SNP genotyping (550K), and we also incorporated
data from a published study (n = 266). We found that
∼30% of SNP-expression correlations in one study failed to replicate
in either of the others, even at thresholds yielding high reproducibility in
simulations, and we quantified numerous factors affecting reproducibility. Our
data suggest that drug exposure, clinical descriptors, and unknown factors
associated with tissue ascertainment and analysis have substantial effects on
gene expression and that controlling for hidden confounding variables
significantly increases replication rate. Furthermore, we found that
reproducible eQTL SNPs were heavily enriched near gene starts and ends, and
subsequently resequenced the promoters and 3′UTRs for 14 genes and tested
the identified haplotypes using luciferase assays. For three genes, significant
haplotype-specific in vitro functional differences correlated
directly with expression levels, suggesting that many bona fide
eQTLs result from functional variants that can be mechanistically isolated in a
high-throughput fashion. Finally, given our study design, we were able to
discover and validate hundreds of liver eQTLs. Many of these relate directly to
complex traits for which liver-specific analyses are likely to be relevant, and
we identified dozens of potential connections with disease-associated loci.
These included previously characterized eQTL contributors to diabetes, drug
response, and lipid levels, and they suggest novel candidates such as a role for
NOD2 expression in leprosy risk and
C2orf43 in prostate cancer. In general, the work presented
here will be valuable for future efforts to precisely identify and functionally
characterize genetic contributions to a variety of complex traits
Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019
Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens
Vaccine efficacy of ALVAC-HIV and bivalent subtype C gp120–MF59 in adults
BACKGROUND : A safe, effective vaccine is essential to eradicating human immunodeficiency virus (HIV) infection. A canarypox–protein HIV vaccine regimen (ALVAC-HIV plus AIDSVAX B/E) showed modest efficacy in reducing infection in Thailand. An analogous regimen using HIV-1 subtype C virus showed potent humoral and cellular responses in a phase 1–2a trial in South Africa. Efficacy data and additional safety data were needed for this regimen in a larger population in South Africa. METHODS : In this phase 2b–3 trial, we randomly assigned 5404 adults without HIV-1 infection to receive the vaccine (2704 participants) or placebo (2700 participants). The vaccine regimen consisted of injections of ALVAC-HIV at months 0 and 1, followed by four booster injections of ALVAC-HIV plus bivalent subtype C gp120–MF59 adjuvant at months 3, 6, 12, and 18. The primary efficacy outcome was the occurrence of HIV-1 infection from randomization to 24 months. RESULTS : In January 2020, prespecified criteria for non-efficacy were met at an interim analysis; further vaccinations were subsequently halted. The median age of the trial participants was 24 years; 70% of the participants were women. The incidence of adverse events was similar in the vaccine and placebo groups. During the 24-month followup, HIV-1 infection was diagnosed in 138 participants in the vaccine group and in 133 in the placebo group (hazard ratio, 1.02; 95% confidence interval, 0.81 to 1.30; P = 0.84). CONCLUSIONS : The ALVAC–gp120 regimen did not prevent HIV-1 infection among participants in South Africa despite previous evidence of immunogenicity.Supported by grants (HHSN272201300033C and HHSN272201600012C)
to Novartis Vaccines and Diagnostics (now part of the
GlaxoSmithKline [GSK] Biologicals) by the National Institute of
Allergy and Infectious Diseases (NIAID) of the National Institutes
of Health (NIH) for the selection and process development of the
two gp120 envelope proteins TV1.C and 1086.C; by the Bill and
Melinda Gates Foundation Global Health Grant (OPP1017604)
and NIAID for the manufacture and release of the gp120 clinical
grade material; and by U.S. Public Health Service Grants — UM1
AI068614 to the HIV Vaccine Trials Network (HVTN), UM1
AI068635 to the HVTN Statistical and Data Management Center,
and UM1 AI068618 to the HVTN Laboratory Center — from the
NIAID. GSK Biologicals contributed financially to the provision of
preexposure prophylaxis to trial participants. The South African
Medical Research Council supported its affiliated research sites.http://www.nejm.orgam2022School of Health Systems and Public Health (SHSPH
Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c
Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose
diabetes, but may identify different people as having diabetes. We used data from 117
population-based studies and quantified, in different world regions, the prevalence of
diagnosed diabetes, and whether those who were previously undiagnosed and detected
as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed
prediction equations for estimating the probability that a person without previously
diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa.
The age-standardised proportion of diabetes that was previously undiagnosed, and
detected in survey screening, ranged from 30% in the high-income western region to 66%
in south Asia. Among those with screen-detected diabetes with either test, the agestandardised
proportion who had elevated levels of both FPG and HbA1c was 29-39%
across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and
middle-income regions, isolated elevated HbA1c more common than isolated elevated
FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and
underestimate diabetes prevalence. Our prediction equations help allocate finite
resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and
surveillance.peer-reviewe
Methylphenidate For Apathy In Community-Dwelling Older Veterans With Mild Alzheimer\u27S Disease: A Double-Blind, Randomized, Placebo-Controlled Trial
Objective: Apathy is a common behavioral problem in Alzheimer\u27s disease. Apathy has profound consequences, such as functional impairment, higher service utilization, higher caregiver burden, and increased mortality. The authors\u27 objective was to study the effects of methylphenidate on apathy in Alzheimer\u27s disease. Method: A 12-week, prospective, double-blind, randomized, placebo-controlled trial (methylphenidate versus placebo) was conducted in community-dwelling veterans (N=60) with mild Alzheimer\u27s disease. The primary outcome for apathy (Apathy Evaluation Scale-Clinician) and secondary outcomes forcognition(Mini-Mental State Examination, Modified Mini-Mental State Examination), functional status (activities of daily living, instrumental activities of daily living), improvement and severity (Clinical Global Impressions Scale [CGI]), caregiver burden (Zarit Burden Scale), and depression (Cornell Scale for Depression in Dementia) were measured at baseline and at 4, 8, and 12 weeks. Results: Participants were all men (77 years old, SD=8). After adjusting for baseline, the methylphenidate group had significantly greater improvement in apathy than the placebo group at 4 weeks, 8 weeks, and 12 weeks. At 12 weeks, there was also greater improvement in cognition, functional status, caregiver burden, CGI scores, and depression in the methylphenidate group compared with the placebo group. Conclusions: Methylphenidate improved apathy in a group of community-dwelling veterans with mild Alzheimer\u27s disease. Methylphenidate also improved cognition, functional status, caregiver burden, CGI scores, and depression
Data quality in an HIV vaccine efficacy clinical trial in South Africa: through natural disasters and with discipline
Abstract Background To produce quality data that informs valid clinical trial results and withstands regulatory inspection, trial sites should adhere to many complex and dynamic requirements. Understanding non-conformance to requirements informs the emerging field of improvement science. We describe protocol deviations in South Africa’s largest HIV vaccine efficacy trial. Methods We analysed data from the HVTN 702 trial using mixed methods. We obtained descriptive statistics, from protocol deviation case report forms collected from 2016–2022, of deviation by participant, trial site, and time to site awareness. We thematically analysed text narratives of deviation descriptions, corrective and preventive actions, generating categories, codes and themes which emerged from the data. Results For 5407 enrollments, 4074 protocol deviations were reported (75 [95% CI: 73.0–77.6] deviations per 100 enrolments). There was a median of 1 protocol deviation per participant (IQR 1–2). Median time from deviation to site awareness was 31 days (IQR 0–146). The most common category of deviation type was omitted data and/or procedures (69%), and 54% of these omissions were stated to have arisen because of the national lockdown at the beginning of the COVID-19 pandemic. The ratio of protocol deviations to cumulative enrolments was highest in the year 2020 (0.34). Major themes of deviations were: COVID-19 and climate disasters giving rise to deviation trends, subroutines introducing an opportunity for deviation, and document fragmentation (such as requirements dispersed across multiple guidance documents) as an obstacle. Preventive action categories were: no preventive measures; discipline, training and/or awareness; quality review, checking and verifying and changing the process and/or implementation tools. Major themes of preventive actions were that systems-based actions are unusual, with people-based actions dominating, and that root cause analysis was rarely mentioned. Conclusions In the age of infectious and climate disaster risks, trials may benefit from simple study designs and trial-related documents. To optimise protocol adherence, sponsors and sites should consider ongoing training, and routinely review deviation reports with a view to adjusting processes. These data quality lessons may inform future trial design, training and implementation. Trial registration HVTN 702 was registered with the South African National Clinical Trials Register (DOH-27–0916-5327) and ClinicalTrials.gov ( NCT02968849 )