2,564 research outputs found
Gestational diabetes in women living with HIV in the UK and Ireland: insights from population-based surveillance data
INTRODUCTION: The prevalence of gestational diabetes (GD) is increasing globally. While universal risk factors for GD are reasonably well understood, questions remain regarding risks for women living with HIV (WLWH). We aimed to describe GD prevalence, evaluate associated maternal risk factors and assess specific birth outcomes in WLWH in the UK and Ireland. METHODS: We analysed all pregnancies (≥24 weeks' gestation) in women diagnosed with HIV before delivery, reported to the UK-based Integrated Screening Outcomes Surveillance Service between 2010 and 2020. Every report of GD was considered as a case. A multivariable logistic regression model, adjusted for women with more than one pregnancy fitted with generalized estimating equations (GEE) assessed the effect of independent risk factors. RESULTS: There were 10,553 pregnancies in 7916 women, of which 460 (4.72%) pregnancies had reported GD. Overall, the median maternal age was 33 years (Q1:29-Q3:37), and 73% of pregnancies were in Black African women. WLWH with GD (WLWH-GD) were older (61% vs. 41% aged ≥35 years, p 350 cells/μl (GEE-aOR: 0.73, 95% CI: 0.50-0.96). CONCLUSIONS: GD prevalence increased over time among WLWH but was not significantly different from the general population. Maternal age, ethnicity and CD4 count were risk factors based on available data. Stillbirth and preterm delivery were more common in WLWH-GD than other WLWH over the study period. Further studies are required to build upon these results
Gestational diabetes in women living with HIV in the UK and Ireland: insights from population-based surveillance data
INTRODUCTION: The prevalence of gestational diabetes (GD) is increasing globally. While universal risk factors for GD are reasonably well understood, questions remain regarding risks for women living with HIV (WLWH). We aimed to describe GD prevalence, evaluate associated maternal risk factors and assess specific birth outcomes in WLWH in the UK and Ireland. METHODS: We analysed all pregnancies (≥24 weeks' gestation) in women diagnosed with HIV before delivery, reported to the UK-based Integrated Screening Outcomes Surveillance Service between 2010 and 2020. Every report of GD was considered as a case. A multivariable logistic regression model, adjusted for women with more than one pregnancy fitted with generalized estimating equations (GEE) assessed the effect of independent risk factors. RESULTS: There were 10,553 pregnancies in 7916 women, of which 460 (4.72%) pregnancies had reported GD. Overall, the median maternal age was 33 years (Q1:29-Q3:37), and 73% of pregnancies were in Black African women. WLWH with GD (WLWH-GD) were older (61% vs. 41% aged ≥35 years, p 350 cells/μl (GEE-aOR: 0.73, 95% CI: 0.50-0.96). CONCLUSIONS: GD prevalence increased over time among WLWH but was not significantly different from the general population. Maternal age, ethnicity and CD4 count were risk factors based on available data. Stillbirth and preterm delivery were more common in WLWH-GD than other WLWH over the study period. Further studies are required to build upon these results
MicroRNAs miR-203-3p, miR-664-3p and miR-708-5p are associated with median strain lifespan in mice
This is the final version of the article. Available from Springer Nature via the DOI in this record.MicroRNAs (miRNAs) are small non-coding RNA species that have been shown to have roles in multiple processes that occur in higher eukaryotes. They act by binding to specific sequences in the 3' untranslated region of their target genes and causing the transcripts to be degraded by the RNA-induced silencing complex (RISC). MicroRNAs have previously been reported to demonstrate altered expression in several aging phenotypes such as cellular senescence and age itself. Here, we have measured the expression levels of 521 small regulatory microRNAs (miRNAs) in spleen tissue from young and old animals of 6 mouse strains with different median strain lifespans by quantitative real-time PCR. Expression levels of 3 microRNAs were robustly associated with strain lifespan, after correction for multiple statistical testing (miR-203-3p [β-coefficient = -0.6447, p = 4.8 × 10(-11)], miR-664-3p [β-coefficient = 0.5552, p = 5.1 × 10(-8)] and miR-708-5p [β-coefficient = 0.4986, p = 1.6 × 10(-6)]). Pathway analysis of binding sites for these three microRNAs revealed enrichment of target genes involved in key aging and longevity pathways including mTOR, FOXO and MAPK, most of which also demonstrated associations with longevity. Our results suggests that miR-203-3p, miR-664-3p and miR-708-5p may be implicated in pathways determining lifespan in mammals.This work was funded by the Wellcome Trust (grant number WT097835MF to D. Melzer and L.W. Harries), and the NIH-NIA (grant number AG038070 to The Jackson Laboratory)
Changes in the expression of splicing factor transcripts and variations in alternative splicing are associated with lifespan in mice and humans
This is the final version of the article. Available from the publisher via the DOI in this record.Dysregulation of splicing factor expression and altered alternative splicing are associated with aging in humans and other species, and also with replicative senescence in cultured cells. Here, we assess whether expression changes of key splicing regulator genes and consequent effects on alternative splicing are also associated with strain longevity in old and young mice, across 6 different mouse strains with varying lifespan (A/J, NOD.B10Sn-H2(b) /J, PWD.Phj, 129S1/SvlmJ, C57BL/6J and WSB/EiJ). Splicing factor expression and changes to alternative splicing were associated with strain lifespan in spleen and to a lesser extent in muscle. These changes mainly involved hnRNP splicing inhibitor transcripts with most changes more marked in spleens of young animals from long-lived strains. Changes in spleen isoform expression were suggestive of reduced cellular senescence and retained cellular proliferative capacity in long-lived strains. Changes in muscle isoform expression were consistent with reduced pro-inflammatory signalling in longer-lived strains. Two splicing regulators, HNRNPA1 and HNRNPA2B1, were also associated with parental longevity in humans, in the InCHIANTI aging study. Splicing factors may represent a driver, mediator or early marker of lifespan in mouse, as expression differences were present in the young animals of long-lived strains. Changes to alternative splicing patterns of key senescence genes in spleen and key remodelling genes in muscle suggest that correct regulation of alternative splicing may enhance lifespan in mice. Expression of some splicing factors in humans was also associated with parental longevity, suggesting that splicing regulation may also influence lifespan in humans.The authors would like to acknowledge the Wellcome Trust (grant
number WT097835MF LWH, DM), and NIH-NIA grant number
AG038070 to The Jackson Laboratory for providing the funding for this
study
circRNAs expressed in human peripheral blood are associated with human aging phenotypes, cellular senescence and mouse lifespan
This is the final version. Available from Springer via the DOI in this record. Circular RNAs (circRNAs) are an emerging class of non-coding RNA molecules that are thought to regulate gene expression and human disease. Despite the observation that circRNAs are known to accumulate in older organisms and have been reported in cellular senescence, their role in aging remains relatively unexplored. Here, we have assessed circRNA expression in aging human blood and followed up age-associated circRNA in relation to human aging phenotypes, mammalian longevity as measured by mouse median strain lifespan and cellular senescence in four different primary human cell types. We found that circRNAs circDEF6, circEP300, circFOXO3 and circFNDC3B demonstrate associations with parental longevity or hand grip strength in 306 subjects from the InCHIANTI study of aging, and furthermore, circFOXO3 and circEP300 also demonstrate differential expression in one or more human senescent cell types. Finally, four circRNAs tested showed evidence of conservation in mouse. Expression levels of one of these, circPlekhm1, was nominally associated with lifespan. These data suggest that circRNA may represent a novel class of regulatory RNA involved in the determination of aging phenotypes, which may show future promise as both biomarkers and future therapeutic targets for age-related disease.University of Exeter, Medical Research Council Clinical Infrastructure awardWellcome TrustBBSRC LOLANI
Prolonged systemic inflammation and damage to the vascular endothelium following intratracheal instillation of air pollution nanoparticles in rats
BACKGROUND: Exposure to air pollution is associated with cardiovascular disease, including increased morbidity and mortality rates.
OBJECTIVE: The aim of this investigation was to assess the effect, in rats, of intratracheal instillation of particulate air pollution on biomarkers of leucocyte activation and vascular endothelial damage.
METHODS: Air pollution particles (PM10) were instilled into rats, and blood samples were taken three days and six weeks post instillation. Plasma neutrophil elastase and VonWillebrand factor were measured by ELISA.
RESULTS: Plasma neutrophil elastase increased from 175±44 ng/ml at baseline to 288±26 ng/ml 3 days post instillation (p=0.038). vWF increased from 0.160±0.015 IU/ml at baseline to 0.224±0.015 IU/ml at 3 days post and 0.208±0.01 IU/ml at 6 weeks post (p=0.006, ANOVA). sICAM-1 increased from 17.75±0.70 ng/ml at baseline to 19.03±0.33 ng/ml at 3 days post and 21.72±1.16 ng/ml at 6 weeks post (p=0.009, ANOVA).
CONCLUSION: Instillation caused prolonged systemic inflammation, activation of blood leucocytes and damage to the vascular endothelium
Reproducibility of measurements of potential doubling time of tumour cells in the multicentre National Cancer Institute protocol T92-0045
We compared the flow cytometric measurement and analysis of the potential doubling time (Tpot) between three centres involved in the National Cancer Institute (NCI) protocol T92-0045. The primary purpose was to understand and minimize the variation within the measurement. A total of 102 specimens were selected at random from patients entered into the trial. Samples were prepared, stained, run and analysed in each centre and a single set of data analysed by all three centres. Analysis of the disc data set revealed that the measurement of labelling index (LI) was robust and reproducible. The estimation of duration of S-phase (Ts) was subject to errors of profile interpretation, particularly DNA ploidy status, and analysis. The LI dominated the variation in Tpot such that the level of final agreement, after removal of outliers and ploidy agreement, reached correlation coefficients of 0.9. The sample data showed poor agreement within each of the components of the measurement. There was some improvement when ploidy was in agreement, but correlation coefficients failed to exceed values of 0.5 for Tpot. The data suggest that observer-associated analysis of Ts and tissue processing and tumour heterogeneity were the major causes of variability in the Tpot measurement. The first two aspects can be standardized and minimized, but heterogeneity will remain a problem with biopsy techniques. © 1999 Cancer Research Campaig
Mouse Gestation Length Is Genetically Determined
Background: Preterm birth is an enormous public health problem, affecting over 12 % of live births and costing over $26 billion in the United States alone. The causes are complex, but twin studies support the role of genetics in determining gestation length. Despite widespread use of the mouse in studies of the genetics of preterm birth, there have been few studies that actually address the precise natural gestation length of the mouse, and to what degree the timing of labor and birth is genetically determined. Methodology/Principal Findings: To further develop the mouse as a genetic model of preterm birth, we developed a highthroughput monitoring system and measured the gestation length in 15 inbred strains. Our results show an unexpectedly wide variation in overall gestation length between strains that approaches two full days, while intra-strain variation is quite low. Although litter size shows a strong inverse correlation with gestation length, genetic difference alone accounts for a significant portion of the variation. In addition, ovarian transplant experiments support a primary role of maternal genetics in the determination of gestation length. Preliminary analysis of gestation length in the C57BL/6J-Chr # A/J /NaJ chromosome substitution strain (B.A CSS) panel suggests complex genetic control of gestation length. Conclusions/Significance: Together, these data support the role of genetics in regulating gestation length and present th
Peritrophic matrix of Phlebotomus duboscqi and its kinetics during Leishmania major development
Light microscopy of native preparations, histology, and electron microscopy have revealed that Phlebotomus duboscqi belongs to a class of sand fly species with prompt development of the peritrophic matrix (PM). Secretion of electron-lucent fibrils, presumably chitin, starts immediately after the ingestion of a blood meal and, about 6 h later, is followed by secretion of amorphous electron-dense components, presumably proteins and glycoproteins. The PM matures in less than 12 h and consists of a thin laminar outer layer and a thick amorphous inner layer. No differences have been found in the timing of the disintegration of the PM in females infected with Leishmania major. In both groups of females (infected and uninfected), the disintegration of the PM is initiated at the posterior end. Although parasites are present at high densities in the anterior part of the blood meal bolus, they escape from the PM at the posterior end only. These results suggest that L. major chitinase does not have an important role in parasite escape from the PM. Promastigotes remain in the intraperitrophic space until the PM is broken down by sand-fly-derived chitinases and only then migrate anteriorly. Disintegration of the PM occurs simultaneously with the morphological transformation of parasites from procyclic forms to long nectomonads. A novel role is ascribed to the anterior plug, a component of the PM secreted by the thoracic midgut; this plug functions as a temporary barrier to stop the forward migration of nectomonads to the thoracic midgut
Genetic analysis of lung function in inbred mice suggests vitamin D receptor as a candidate gene
Vitamin D receptor (VDR) polymorphisms are associated with an increased asthma incidence in human populations; however, observations in Vdr knockout mice are unclear. The aim of our study was to determine the influence of the genetic variation in Vdr among inbred strains on lung resistance (i.e., dynamic and airway resistance). In an intercross between the strains C57BL/6J (B6) and KK/HlJ (KK), we identified that a significant QTL for dynamic resistance on Chr X was interacting with a QTL on Chr 15. The Chr 15 QTL peak was located in close proximity to the Vdr locus. We further examined if phenotypes of several inbred strains with varying Vdr genotypes differed. Strains with a B6-like genotype on the Vdr locus had significantly lower airway resistance than strains with a KK-like genotype. Vdr knockout mice were examined for dynamic resistance and showed significantly higher resistance than mice with one (i.e., heterozygous) or both copies (i.e., wild-type) of the Vdr. In comparison to B6, the strain A/J is more resistant but carries the same genotype at the Vdr locus. Dietary vitamin D manipulation in the strain A/J did not rescue the high airway resistance phenotype. Finally, we observed that serum vitamin D does not correlate significantly with lung resistance parameters in a survey of 18 strains. Conclusively, Vdr contributes to the phenotypic variation of lung resistance in inbred mice but other molecules in the Vdr pathway and extended network [i.e., Chr X gene(s)] may contribute as well
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