944 research outputs found
Mediation analysis of gestational age, congenital heart defects, and infant birth-weight
Background
In this study we assessed the mediation role of the gestational age on the effect of the infantâs congenital heart defects (CHD) on birth-weight. Methods
We used secondary data from the Baltimore-Washington Infant Study (1981â1989). Mediation analysis was employed to investigate whether gestational age acted as a mediator of the association between CHD and reduced birth-weight. We estimated the mediated effect, the mediation proportion, and their corresponding 95% confidence intervals (CI) using several methods. Results
There were 3362 CHD cases and 3564 controls in the dataset with mean birth-weight of 3071 (SDâ=â729) and 3353 (SDâ=â603) grams, respectively; the mean gestational age was 38.9 (SDâ=â2.7) and 39.6 (SDâ=â2.2) weeks, respectively. After adjusting for covariates, the estimated mediated effect by gestational age was 113.5 grams (95% CI, 92.4â134.2) and the mediation proportion was 40.7% (95% CI, 34.7%â46.6%), using the bootstrap approach. Conclusions
Gestational age may account for about 41% of the overall effect of heart defects on reduced infant birth-weight. Improved prenatal care and other public health efforts that promote full term delivery, particularly targeting high-risk families and mothers known to be carrying a fetus with CHD, may therefore be expected to improve the birth-weight of these infants and their long term health
Mediation analysis of gestational age, congenital heart defects, and infant birth-weight
Abstract Background In this study we assessed the mediation role of the gestational age on the effect of the infantâs congenital heart defects (CHD) on birth-weight. Methods We used secondary data from the Baltimore-Washington Infant Study (1981â1989). Mediation analysis was employed to investigate whether gestational age acted as a mediator of the association between CHD and reduced birth-weight. We estimated the mediated effect, the mediation proportion, and their corresponding 95% confidence intervals (CI) using several methods. Results There were 3362 CHD cases and 3564 controls in the dataset with mean birth-weight of 3071 (SDâ=â729) and 3353 (SDâ=â603) grams, respectively; the mean gestational age was 38.9 (SDâ=â2.7) and 39.6 (SDâ=â2.2) weeks, respectively. After adjusting for covariates, the estimated mediated effect by gestational age was 113.5 grams (95% CI, 92.4â134.2) and the mediation proportion was 40.7% (95% CI, 34.7%â46.6%), using the bootstrap approach. Conclusions Gestational age may account for about 41% of the overall effect of heart defects on reduced infant birth-weight. Improved prenatal care and other public health efforts that promote full term delivery, particularly targeting high-risk families and mothers known to be carrying a fetus with CHD, may therefore be expected to improve the birth-weight of these infants and their long term health
Adherence to clinical follow-up recommendations for liver function tests: A cross-sectional study of patients with HCV and their associated risk behaviors
This study examined whether patients with Hepatitis C virus (HCV) infection adhered to their physicians\u27 recommendation and HCV clinical guidelines for obtaining a regular liver function test (LFT), and whether high-risk behaviors are associated with behavioral adherence. A cross-sectional survey was administered to 101 eligible patients with HCV who were recruited from health centers in New Jersey and Washington, DC. Adherence outcomes were defined as the patients\u27 self-report of two consecutive receipts of LFTs in accordance with their physicians\u27 recommended interval or the clinical guidelines for a LFT within 3-6 months. 67.4% of patients (66/98) reported a receipt of their physicians\u27 recommendation for a LFT. The rate of adherence to physician recommendation was about 70% (46/66), however over 50% (52/101) of patients with HCV did not obtain regular LFTs. 15.8% (16/101) of patients continued to use injection drugs. Patients who used injection drugs had 0.87 (adjusted odds ratio (aOR) = 0.13, 95% confidence interval 0.03-0.59) times lower odds adhering to their physician recommendation, relative to non-users. Patients with HIV co-infection had increased odds of adhering to the clinical guidelines (odds ratio 3.41, 95% confidence interval 1.34-8.70) vs. patients who did not report HIV co-infection. Additionally, patients who had received a physician\u27s recommendation had 7.21 times (95% confidence interval of 2.36-22.2) greater odds adhering to the clinical guidelines than those who had not. Overall, promoting HCV patient-provider communication regarding regular LFTs and reduction of risk behaviors is essential for preventing patients from HCV-related liver disease progression
Familial co-occurrence of congenital heart defects follows distinct patterns
Aims Congenital heart defects (CHD) affect almost 1% of all live born children and the number of adults with CHD is increasing. In families where CHD has occurred previously, estimates of recurrence risk, and the type of recurring malformation are important for counselling and clinical decision-making, but the recurrence patterns in families are poorly understood. We aimed to determine recurrence patterns, by investigating the co-occurrences of CHD in 1163 families with known malformations, comprising 3080 individuals with clinically confirmed diagnosis. Methods and results We calculated rates of concordance and discordance for 41 specific types of malformations, observing a high variability in the rates of concordance and discordance. By calculating odds ratios for each of 1640 pairs of discordant lesions observed between affected family members, we were able to identify 178 pairs of malformations that co-occurred significantly more or less often than expected in families. The data show that distinct groups of cardiac malformations co-occur in families, suggesting influence from underlying developmental mechanisms. Analysis of human and mouse susceptibility genes showed that they were shared in 19% and 20% of pairs of co-occurring discordant malformations, respectively, but none of malformations that rarely co-occur, suggesting that a significant proportion of co-occurring lesions in families is caused by overlapping susceptibility genes. Conclusion Familial CHD follow specific patterns of recurrence, suggesting a strong influence from genetically regulated developmental mechanisms. Co-occurrence of malformations in families is caused by shared susceptibility genes
Functional analysis of frequently expressed Chinese rhesus macaque MHC class I molecules Mamu-A1*02601 and Mamu-B*08301 reveals HLA-A2 and HLA-A3 supertypic specificities
The Simian immunodeficiency virus (SIV)-infected Indian rhesus macaque (Macaca mulatta) is the most established model of HIV infection and AIDS-related research, despite the potential that macaques of Chinese origin is a more relevant model. Ongoing efforts to further characterize the Chinese rhesus macaquesâ major histocompatibility complex (MHC) for composition and function should facilitate greater utilization of the species. Previous studies have demonstrated that Chinese-origin M. mulatta (Mamu) class I alleles are more polymorphic than their Indian counterparts, perhaps inferring a model more representative of human MHC, human leukocyte antigen (HLA). Furthermore, the Chinese rhesus macaque class I allele Mamu-A1*02201, the most frequent allele thus far identified, has recently been characterized and shown to be an HLA-B7 supertype analog, the most frequent supertype in human populations. In this study, we have characterized two additional alleles expressed with high frequency in Chinese rhesus macaques, Mamu-A1*02601 and Mamu-B*08301. Upon the development of MHCâpeptide-binding assays and definition of their associated motifs, we reveal that these Mamu alleles share peptide-binding characteristics with the HLA-A2 and HLA-A3 supertypes, respectively, the next most frequent human supertypes after HLA-B7. These data suggest that Chinese rhesus macaques may indeed be a more representative model of HLA gene diversity and function as compared to the species of Indian origin and therefore a better model for investigating human immune responses
The most common Chinese rhesus macaque MHC class I molecule shares peptide binding repertoire with the HLA-B7 supertype
Of the two rhesus macaque subspecies used for AIDS studies, the Simian immunodeficiency virus-infected Indian rhesus macaque (Macaca mulatta) is the most established model of HIV infection, providing both insight into pathogenesis and a system for testing novel vaccines. Despite the Chinese rhesus macaque potentially being a more relevant model for AIDS outcomes than the Indian rhesus macaque, the Chinese-origin rhesus macaques have not been well-characterized for their major histocompatibility complex (MHC) composition and function, reducing their greater utilization. In this study, we characterized a total of 50 unique Chinese rhesus macaques from several varying origins for their entire MHC class I allele composition and identified a total of 58 unique complete MHC class I sequences. Only nine of the sequences had been associated with Indian rhesus macaques, and 28/58 (48.3%) of the sequences identified were novel. From all MHC alleles detected, we prioritized Mamu-A1*02201 for functional characterization based on its higher frequency of expression. Upon the development of MHC/peptide binding assays and definition of its associated motif, we revealed that this allele shares peptide binding characteristics with the HLA-B7 supertype, the most frequent supertype in human populations. These studies provide the first functional characterization of an MHC class I molecule in the context of Chinese rhesus macaques and the first instance of HLA-B7 analogy for rhesus macaques
MicroRNA-9 as Potential Biomarker for Breast Cancer Local Recurrence and Tumor Estrogen Receptor Status
MicroRNAs (miRs) are small, non-protein coding transcripts involved in many cellular functions. Many miRs have emerged as important cancer biomarkers. In the present study, we investigated whether miR levels in breast tumors are predictive of breast cancer local recurrence (LR). Sixty-eight women who were diagnosed with breast cancer at the Lombardi Comprehensive Cancer Center were included in this study. Breast cancer patients with LR and those without LR were matched on year of surgery, age at diagnosis, and type of surgery. Candidate miRs were identified by screening the expression levels of 754 human miRs using miR arrays in 16 breast tumor samples from 8 cases with LR and 8 cases without LR. Eight candidate miRs that showed significant differences between tumors with and without LR were further verified in 52 tumor samples using real-time PCR. Higher expression of miR-9 was significantly associated with breast cancer LR in all cases as well as the subset of estrogen receptor (ER) positive cases (pâ=â0.02). The AUCs (Area Under Curve) of receiver operating characteristic (ROC) curves of miR-9 for all tumors and ER positive tumors are 0.68 (pâ=â0.02) and 0.69 (pâ=â0.02), respectively. In ER positive cases, Kaplan-Meier analysis showed that patients with lower miR-9 levels had significantly better 10-year LR-free survival (67.9% vs 30.8%, pâ=â0.02). Expression levels of miR-9 and another miR candidate, miR-375, were also strongly associated with ER status (p<0.001 for both). The potential of miR-9 as a biomarker for LR warrants further investigation with larger sample size
Environmental, maternal, and reproductive risk factors for childhood acute lymphoblastic leukemia in Egypt : a case-control study
BACKGROUND\ud
Acute lymphocytic leukemia (ALL) is the most common pediatric cancer. The exact cause is not known in most cases, but past epidemiological research has suggested a number of potential risk factors. This study evaluated associations between environmental and parental factors and the risk for ALL in Egyptian children to gain insight into risk factors in this developing country.\ud
METHODS\ud
We conducted a case-control design from May 2009 to February 2012. Cases were recruited from Children's Cancer Hospital, Egypt (CCHE). Healthy controls were randomly selected from the general population to frequency-match the cumulative group of cases by sex, age groups (<1; 1 - 5; >5 - 10; >10Â years) and region of residence (Cairo metropolitan region, Nile Delta region (North), and Upper Egypt (South)). Mothers provided answers to an administered questionnaire about their environmental exposures and health history including those of the father. Odds ratios (ORs) and 95Â % confidence intervals (CI) were calculated using logistic regression with adjustment for covariates.\ud
RESULTS\ud
Two hundred ninety-nine ALL cases and 351 population-based controls frequency-matched for age group, gender and location were recruited. The risk of ALL was increased with the mother's use of medications for ovulation induction (ORadjâ=â2.5, 95Â % CI =1.2 -5.1) and to a lesser extend with her age (ORadjâ=â1.8, 95Â % CIâ=â1.1 - 2.8, for mothers â„ 30Â years old). Delivering the child by Cesarean section, was also associated with increased risk (ORadjâ=â2.01, 95Â % CI =1.24-2.81).\ud
CONCLUSIONS\ud
In Egypt, the risk for childhood ALL appears to be associated with older maternal age, and certain maternal reproductive factors
Combination of the W boson polarization measurements in top quark decays using ATLAS and CMS data at root s=8 TeV
The combination of measurements of the W boson polarization in top quark decays performed by the ATLAS and CMS collaborations is presented. The measurements are based on proton-proton collision data produced at the LHC at a centre-of-mass energy of 8 TeV, and corresponding to an integrated luminosity of about 20 fb(-1)for each experiment. The measurements used events containing one lepton and having different jet multiplicities in the final state. The results are quoted as fractions of W bosons with longitudinal (F-0), left-handed (F-L), or right-handed (F-R) polarizations. The resulting combined measurements of the polarization fractions are F-0= 0.693 +/- 0.014 and F-L= 0.315 +/- 0.011. The fractionF(R)is calculated from the unitarity constraint to be F-R=-0.008 +/- 0.007. These results are in agreement with the standard model predictions at next-to-next-to-leading order in perturbative quantum chromodynamics and represent an improvement in precision of 25 (29)% for F-0(F-L) with respect to the most precise single measurement. A limit on anomalous right-handed vector (V-R), and left- and right-handed tensor (g(L), g(R)) tWb couplings is set while fixing all others to their standard model values. The allowed regions are [-0.11,0.16] for V-R, [-0.08,0.05] for g(L), and [-0.04,0.02] for g(R), at 95% confidence level. Limits on the corresponding Wilson coefficients are also derived.Peer reviewe
A search for the dimuon decay of the Standard Model Higgs boson with the ATLAS detector
A search for the dimuon decay of the Standard Model (SM) Higgs boson is performed using data corresponding to an integrated luminosity of 139 fb(-1) collected with the ATLAS detector in Run 2 pp collisions at root s = 13 TeV at the Large Hadron Collider. The observed (expected) significance over the background-only hypothesis for a Higgs boson with a mass of 125.09 GeV is 2.0 sigma (1.7 sigma). The observed upper limit on the cross section times branching ratio for pp -> H -> mu mu is 2.2 times the SM prediction at 95% confidence level, while the expected limit on a H -> mu mu signal assuming the absence (presence) of a SM signal is 1.1(2.0). The best-fit value of the signal strength parameter, defined as the ratio of the observed signal yield to the one expected in the SM, is mu = 1.2 +/- 0.6. (C) 2020 The Author(s). Published by Elsevier B.V
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