20 research outputs found
Detectable clonal mosaicism and its relationship to aging and cancer
In an analysis of 31,717 cancer cases and 26,136 cancer-free controls from 13 genome-wide association studies, we observed large chromosomal abnormalities in a subset of clones in DNA obtained from blood or buccal samples. We observed mosaic abnormalities, either aneuploidy or copy-neutral loss of heterozygosity, of >2 Mb in size in autosomes of 517 individuals (0.89%), with abnormal cell proportions of between 7% and 95%. In cancer-free individuals, frequency increased with age, from 0.23% under 50 years to 1.91% between 75 and 79 years (P = 4.8 × 10(-8)). Mosaic abnormalities were more frequent in individuals with solid tumors (0.97% versus 0.74% in cancer-free individuals; odds ratio (OR) = 1.25; P = 0.016), with stronger association with cases who had DNA collected before diagnosis or treatment (OR = 1.45; P = 0.0005). Detectable mosaicism was also more common in individuals for whom DNA was collected at least 1 year before diagnosis with leukemia compared to cancer-free individuals (OR = 35.4; P = 3.8 × 10(-11)). These findings underscore the time-dependent nature of somatic events in the etiology of cancer and potentially other late-onset diseases
Childhood bone mineral content is associated with methylation status of the RXRA promoter at birth
Maternal vitamin D deficiency has been associated with reduced offspring bone mineral accrual. Retinoid-X Receptor-alpha (RXRA) is an essential cofactor in the action of 1,25(OH)2-vitamin D, and RXRA methylation in umbilical cord DNA has been associated with later offspring adiposity. We tested the hypothesis that RXRA methylation in umbilical cord DNA collected at birth is associated with offspring skeletal development, assessed by dual-energy X-ray absorptiometry, in a population-based mother-offspring cohort (Southampton Women's Survey). Relationships between maternal plasma 25(OH)-vitamin D concentrations and cord RXRA methylation were also investigated. In 230 children aged 4 years, higher % methylation at 4 out of 6 RXRA CpG sites measured was correlated with lower offspring BMC corrected for body size (??=???2.1 to ?3.4g/SD, p?=?0.002 to 0.047). In a second independent cohort (n?=?64), similar negative associations at two of these CpG sites, but positive associations at the two remaining sites, were observed; however none of the relationships in this replication cohort achieved statistical significance. Maternal free 25(OH)-vitamin D index was negatively associated with methylation at one of these RXRA CpG sites (??=???3.3 SD/unit, p?=?0.03). Thus, perinatal epigenetic marking at the RXRA promoter region in umbilical cord was inversely associated with offspring size-corrected bone mineral content in childhood. The potential mechanistic and functional significance of this finding remains a subject for further investigation.<br/
Do occupational exposures in nuclear refineries contribute to mortality from brain cancer?
Chronic lymphocytic leukaemia: an overview of aetiology in light of recent developments in classification and pathogenesis
Immunocompromised patients with acute respiratory distress syndrome : Secondary analysis of the LUNG SAFE database
The aim of this study was to describe data on epidemiology, ventilatory management, and outcome of acute respiratory distress syndrome (ARDS) in immunocompromised patients. Methods: We performed a post hoc analysis on the cohort of immunocompromised patients enrolled in the Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) study. The LUNG SAFE study was an international, prospective study including hypoxemic patients in 459 ICUs from 50 countries across 5 continents. Results: Of 2813 patients with ARDS, 584 (20.8%) were immunocompromised, 38.9% of whom had an unspecified cause. Pneumonia, nonpulmonary sepsis, and noncardiogenic shock were their most common risk factors for ARDS. Hospital mortality was higher in immunocompromised than in immunocompetent patients (52.4% vs 36.2%; p < 0.0001), despite similar severity of ARDS. Decisions regarding limiting life-sustaining measures were significantly more frequent in immunocompromised patients (27.1% vs 18.6%; p < 0.0001). Use of noninvasive ventilation (NIV) as first-line treatment was higher in immunocompromised patients (20.9% vs 15.9%; p = 0.0048), and immunodeficiency remained independently associated with the use of NIV after adjustment for confounders. Forty-eight percent of the patients treated with NIV were intubated, and their mortality was not different from that of the patients invasively ventilated ab initio. Conclusions: Immunosuppression is frequent in patients with ARDS, and infections are the main risk factors for ARDS in these immunocompromised patients. Their management differs from that of immunocompetent patients, particularly the greater use of NIV as first-line ventilation strategy. Compared with immunocompetent subjects, they have higher mortality regardless of ARDS severity as well as a higher frequency of limitation of life-sustaining measures. Nonetheless, nearly half of these patients survive to hospital discharge. Trial registration: ClinicalTrials.gov, NCT02010073. Registered on 12 December 2013
Ethnic differences translate to inadequacy of high-risk screening for gestational diabetes mellitus in an Asian population: A cohort study
10.1186/1471-2393-14-345BMC Pregnancy and Childbirth141article number 345BPCM