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1.
Katinka P. Bach Carl A. Kuschel Stuart B. Hooper Jean Bertram Sue McKnight Shirley E. Peachey Valerie A. Zahra Sharon J. Flecknoe Mark H. Oliver Megan J. Wallace Frank H. Bloomfield 《PloS one》2012,7(10)
Background
Mechanical ventilation of preterm babies increases survival but can also cause ventilator-induced lung injury (VILI), leading to the development of bronchopulmonary dysplasia (BPD). It is not known whether shear stress injury from gases flowing into the preterm lung during ventilation contributes to VILI.Methods
Preterm lambs of 131 days’ gestation (term = 147 d) were ventilated for 2 hours with a bias gas flow of 8 L/min (n = 13), 18 L/min (n = 12) or 28 L/min (n = 14). Physiological parameters were measured continuously and lung injury was assessed by measuring mRNA expression of early injury response genes and by histological analysis. Control lung tissue was collected from unventilated age-matched fetuses. Data were analysed by ANOVA with a Tukey post-hoc test when appropriate.Results
High bias gas flows resulted in higher ventilator pressures, shorter inflation times and decreased ventilator efficiency. The rate of rise of inspiratory gas flow was greatest, and pulmonary mRNA levels of the injury markers, EGR1 and CTGF, were highest in lambs ventilated with bias gas flows of 18 L/min. High bias gas flows resulted in increased cellular proliferation and abnormal deposition of elastin, collagen and myofibroblasts in the lung.Conclusions
High ventilator bias gas flows resulted in increased lung injury, with up-regulation of acute early response genes and increased histological lung injury. Bias gas flows may, therefore, contribute to VILI and BPD. 相似文献2.
Mohamed A. Elemraid Michelle Muller David A. Spencer Stephen P. Rushton Russell Gorton Matthew F. Thomas Katherine M. Eastham Fiona Hampton Andrew R. Gennery Julia E. Clark 《PloS one》2014,9(8)
Introduction
World Health Organization (WHO) radiological classification remains an important entry criterion in epidemiological studies of pneumonia in children. We report inter-observer variability in the interpretation of 169 chest radiographs in children suspected of having pneumonia.Methods
An 18-month prospective aetiological study of pneumonia was undertaken in Northern England. Chest radiographs were performed on eligible children aged ≤16 years with clinical features of pneumonia. The initial radiology report was compared with a subsequent assessment by a consultant cardiothoracic radiologist. Chest radiographic changes were categorised according to the WHO classification.Results
There was significant disagreement (22%) between the first and second reports (kappa = 0.70, P<0.001), notably in those aged <5 years (26%, kappa = 0.66, P<0.001). The most frequent sources of disagreement were the reporting of patchy and perihilar changes.Conclusion
This substantial inter-observer variability highlights the need for experts from different countries to create a consensus to review the radiological definition of pneumonia in children. 相似文献3.
Esra' Shishtar John L. Sievenpiper Vladimir Djedovic Adrian I. Cozma Vanessa Ha Viranda H. Jayalath David J. A. Jenkins Sonia Blanco Meija Russell J. de Souza Elena Jovanovski Vladimir Vuksan 《PloS one》2014,9(9)
Importance
Despite the widespread use of ginseng in the management of diabetes, supporting evidence of its anti-hyperglycemic efficacy is limited, necessitating the need for evidence-based recommendations for the potential inclusion of ginseng in diabetes management.Objective
To elucidate the effect of ginseng on glycemic control in a systematic review and meta-analysis of randomized controlled trials in people with and without diabetes.Data sources
MEDLINE, EMBASE, CINAHL and the Cochrane Library (through July 3, 2013).Study selection
Randomized controlled trials ≥30 days assessing the glycemic effects of ginseng in people with and without diabetes.Data extraction
Relevant data were extracted by 2 independent reviewers. Discrepancies were resolved by consensus. The Heyland Methodological Quality Score and the Cochrane risk of bias tool were used to assess study quality and risk of bias respectively.Data synthesis
Sixteen trials were included, in which 16 fasting blood glucose (n = 770), 10 fasting plasma insulin (n = 349), 9 glycated hemoglobin (n = 264), and 7 homeostasis model assessment of insulin resistance (n = 305) comparisons were reported. Ginseng significantly reduced fasting blood glucose compared to control (MD = −0.31 mmol/L [95% CI: −0.59 to −0.03], P = 0.03). Although there was no significant effect on fasting plasma insulin, glycated hemoglobin, or homeostasis model assessment of insulin resistance, a priori subgroup analyses did show significant reductions in glycated hemoglobin in parallel compared to crossover trials (MD = 0.22% [95%CI: 0.06 to 0.37], P = 0.01).Limitations
Most trials were of short duration (67% trials<12wks), and included participants with a relatively good glycemic control (median HbA1c non-diabetes = 5.4% [2 trials]; median HbA1c diabetes = 7.1% [7 trials]).Conclusions
Ginseng modestly yet significantly improved fasting blood glucose in people with and without diabetes. In order to address the uncertainty in our effect estimates and provide better assessments of ginseng''s anti-diabetic efficacy, larger and longer randomized controlled trials using standardized ginseng preparations are warranted.Trial Registration
ClinicalTrials.gov NCT01841229 相似文献4.
Background
Rectal washout can prevent local recurrence after anterior resection of rectal cancer. Few studies have focused particularly on the association between irrigation fluids volume or agents and the risk of local recurrence after anterior resection of rectal cancer.Objective
To estimate the association between irrigation fluids types, volumes of rectal washout and risk of local recurrence after anterior resection for cancer.Data Sources
Relevant studies were identified by a search of Medline, Embase, Wiley Online Library, China National Knowledge Infrastructure, Cochrane Oral Health Group Specialized Register, Wanfang databases and Google Website from their inception until October 18,2013.Study Selection
Studies reporting the association between rectal washout types and volumes and risk of local recurrence after anterior resection for cancer were included.Interventions
Eligible studies used rectal washout. Control groups were defined as no washout.Study Appraisal and Synthesis Methods
Random-effects model were used to obtain summary estimates of RR and 95% CI, with Stata version 11 and RevMan 5.2.5 softwares used. The quality of report was appraised in reference to the MINORS item.Results
Of the 919 rectal cancer patients in 8 included studies, a total of 61(6.64%) cases of local recurrence were reported, with a pooled RR 0.51 (95%CI = 0.28–0.92, P = 0.03). The RRs 0.37 and 0.39 in normal saline and washout volume (≥1500 ml normal saline) subgroup, respectively, indicated that rectal washout with normal saline, or ≥1500 ml in volume could significantly reduce local recurrence (LR) rate (95% CI = 0.17–0.79, P = 0.01; 95% CI = 0.18–0.87, P = 0.02) after anterior resection for cancer.Limitation
The included studies were non-randomized observational studies, with diversity of study designs.Conclusion
Rectal washout with normal saline alone can reduce the risk of local recurrence in patients with resectable rectal cancer, and 1.5 liters rectal washout in volume is recommended. 相似文献5.
Background
Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme for folate metabolism in humans; it is encoded by the MTHFR gene. Several studies have assessed the association between MTHFR C677T polymorphism and the risk of congenital heart defects (CHDs), while the results were inconsistent.Methods and Findings
Multiple electronic databases were searched to identify relevant studies published up to July 22, 2012. Data from case-control and TDT studies were integrated in an allelic model using the Catmap and Metafor software. Twenty-nine publications were included in this meta-analysis. The overall meta-analysis showed significant association between MTHFR C677T polymorphism and CHDs risk in children with heterogeneity (P heterogeneity = 0.000) and publication bias (P egger = 0.039), but it turned into null after the trim-and-fill method was implemented (OR = 1.12, 95% CI = 0.95–1.31). Nevertheless, positive results were obtained after stratified by ethnicity and sample size in all subgroups except the mixed population. For mothers, there was significant association between the variant and CHDs without heterogeneity (P heterogeneity = 0.150, OR = 1.16, 95% CI = 1.05–1.29) and publication bias (P egger = 0.981). However, the results varied across each subgroup in the stratified analysis of ethnicity and sample size.Conclusions
Both infant and maternal MTHFR C677T polymorphisms may contribute to the risk of CHDs. 相似文献6.
Background
Psychopharmacotherapy currently constitutes the first-line treatment for depression and anxiety in Parkinson’s disease (PD) however the efficacy of antidepressant treatments in PD is unclear. Several alternative treatments have been suggested as potentially more viable alternatives including dopamine agonists, repetitive transcranial magnetic stimulation, and cognitive behavioural therapy (CBT).Method
A meta-analysis of randomised placebo-controlled trials for depression and/or anxiety in PD was conducted to systematically examine the efficacy of current treatments for depression and anxiety in PD.Results
Nine trials were included. There was only sufficient data to calculate a pooled effect for antidepressant therapies. The pooled effect of antidepressants for depression in PD was moderate but non-significant (d = .71, 95% CI = −1.33 to 3.08). The secondary effect of antidepressants on anxiety in PD was large but also non-significant (d = 1.13, 95% CI = −.67 to 2.94). Two single-trials of non-pharmacological treatments for depression in PD resulted in significant large effects; Omega-3 supplementation (d = .92, 95% CI = .15 to 1.69) and CBT (d = 1.57, 95% CI = 1.06 to 2.07), and warrant further exploration.Conclusions
There remains a lack of controlled trials for both pharmacological and non-pharmacological treatments for depression and anxiety in PD which limits the conclusions which can be drawn. While the pooled effects of antidepressant therapies in PD were non-significant, the moderate to large magnitude of each pooled effect is promising. Non-pharmacological approaches show potential for depression in PD however more research is required. 相似文献7.
Sue Jordan Alan Watkins Mel Storey Steven J. Allen Caroline J. Brooks Iveta Garaiova Martin L. Heaven Ruth Jones Sue F. Plummer Ian T. Russell Catherine A. Thornton Gareth Morgan 《PloS one》2013,8(7)
Background
The vulnerability of clinical trials to volunteer bias is under-reported. Volunteer bias is systematic error due to differences between those who choose to participate in studies and those who do not.Methods and Results
This paper extends the applications of the concept of volunteer bias by using data from a trial of probiotic supplementation for childhood atopy in healthy dyads to explore 1) differences between a) trial participants and aggregated data from publicly available databases b) participants and non-participants as the trial progressed 2) impact on trial findings of weighting data according to deprivation (Townsend) fifths in the sample and target populations. 1) a) Recruits (n = 454) were less deprived than the target population, matched for area of residence and delivery dates (n = 6,893) (mean [SD] deprivation scores 0.09[4.21] and 0.79[4.08], t = 3.44, df = 511, p<0.001). b) i)As the trial progressed, representation of the most deprived decreased. These participants and smokers were less likely to be retained at 6 months (n = 430[95%]) (OR 0.29,0.13–0.67 and 0.20,0.09–0.46), and 2 years (n = 380[84%]) (aOR 0.68,0.50–0.93 and 0.55,0.28–1.09), and consent to infant blood sample donation (n = 220[48%]) (aOR 0.72,0.57–0.92 and 0.43,0.22–0.83). ii)Mothers interested in probiotics or research or reporting infants’ adverse events or rashes were more likely to attend research clinics and consent to skin-prick testing. Mothers participating to help children were more likely to consent to infant blood sample donation. 2) In one trial outcome, atopic eczema, the intervention had a positive effect only in the over-represented, least deprived group. Here, data weighting attenuated risk reduction from 6.9%(0.9–13.1%) to 4.6%(−1.4–+10.5%), and OR from 0.40(0.18–0.91) to 0.56(0.26–1.21). Other findings were unchanged.Conclusions
Potential for volunteer bias intensified during the trial, due to non-participation of the most deprived and smokers. However, these were not the only predictors of non-participation. Data weighting quantified volunteer bias and modified one important trial outcome.Trial Registration
This randomised, double blind, parallel group, placebo controlled trial is registered with the International Standard Randomised Controlled Trials Register, Number (ISRCTN) 26287422. Registered title: Probiotics in the prevention of atopy in infants and children. 相似文献8.
Background
The anticancer effects of legumes have been explored extensively, but evidence from epidemiologic studies on colorectal adenoma is controversial. We performed a meta-analysis to assess these issues.Methods
A systemic search of several databases was conducted for relevant studies evaluating the relationship between legume intake and adenoma risk, with no language restriction, from January 1, 1966, to April 1, 2013.Results
Three cohort and eleven case control studies with 8,380 cases and a total of 101,856 participants were included in the analysis; the pooled odds ratio (95% confidence interval) for the highest vs. lowest consumption categories was 0.83 (0.75–0.93), with moderate level of heterogeneity (I 2 = 25.9% and P = 0.146) based on a random effects model. A decreased risk of adenoma was also observed in most of our subgroup meta-analyses.Conclusions
Higher intake of legumes significantly reduced the risk of colorectal adenoma in our meta-analysis. Nevertheless, due to possible confounders and bias, further investigations are warranted to confirm this relationship. 相似文献9.
Safari M. Kinung'hi Pascal Magnussen Godfrey M. Kaatano Coleman Kishamawe Birgitte J. Vennervald 《PloS one》2014,9(1)
Background
Malaria, schistosomiasis and soil transmitted helminth infections (STH) are important parasitic infections in Sub-Saharan Africa where a significant proportion of people are exposed to co-infections of more than one parasite. In Tanzania, these infections are a major public health problem particularly in school and pre-school children. The current study investigated malaria and helminth co-infections and anaemia in school and pre-school children in Magu district, Tanzania.Methodology
School and pre-school children were enrolled in a cross-sectional study. Stool samples were examined for Schistosoma mansoni and STH infections using Kato Katz technique. Urine samples were examined for Schistosoma haematobium using the urine filtration method. Blood samples were examined for malaria parasites and haemoglobin concentrations using the Giemsa stain and Haemoque methods, respectively.Principal Findings
Out of 1,546 children examined, 1,079 (69.8%) were infected with one or more parasites. Malaria-helminth co-infections were observed in 276 children (60% of all children with P. falciparum infection). Malaria parasites were significantly more prevalent in hookworm infected children than in hookworm free children (p = 0.046). However, this association was non-significant on multivariate logistic regression analysis (OR = 1.320, p = 0.064). Malaria parasite density decreased with increasing infection intensity of S. mansoni and with increasing number of co-infecting helminth species. Anaemia prevalence was 34.4% and was significantly associated with malaria infection, S. haematobium infection and with multiple parasite infections. Whereas S. mansoni infection was a significant predictor of malaria parasite density, P. falciparum and S. haematobium infections were significant predictors of anaemia.Conclusions/Significance
These findings suggest that multiple parasite infections are common in school and pre-school children in Magu district. Concurrent P. falciparum, S. mansoni and S. haematobium infections increase the risk of lower Hb levels and anaemia, which in turn calls for integrated disease control interventions. The associations between malaria and helminth infections detected in this study need further investigation. 相似文献10.
Isaac R. Galatzer-Levy Yael Ankri Sara Freedman Yossi Israeli-Shalev Pablo Roitman Moran Gilad Arieh Y. Shalev 《PloS one》2013,8(8)
Context
Uncovering heterogeneities in the progression of early PTSD symptoms can improve our understanding of the disorder''s pathogenesis and prophylaxis.Objectives
To describe discrete symptom trajectories and examine their relevance for preventive interventions.Design
Latent Growth Mixture Modeling (LGMM) of data from a randomized controlled study of early treatment. LGMM identifies latent longitudinal trajectories by exploring discrete mixture distributions underlying observable data.Setting
Hadassah Hospital unselectively receives trauma survivors from Jerusalem and vicinity.Participants
Adult survivors of potentially traumatic events consecutively admitted to the hospital''s emergency department (ED) were assessed ten days and one-, five-, nine- and fifteen months after ED admission. Participants with data at ten days and at least two additional assessments (n = 957) were included; 125 received cognitive behavioral therapy (CBT) between one and nine months.Approach
We used LGMM to identify latent parameters of symptom progression and tested the effect of CBT on these parameters. CBT consisted of 12 weekly sessions of either cognitive therapy (n = 41) or prolonged exposure (PE, n = 49), starting 29.8±5.7 days after ED admission, or delayed PE (n = 35) starting at 151.8±42.4 days. CBT effectively reduced PTSD symptoms in the entire sample.Main Outcome Measure
Latent trajectories of PTSD symptoms; effects of CBT on these trajectories.Results
Three trajectories were identified: Rapid Remitting (rapid decrease in symptoms from 1- to 5-months; 56% of the sample), Slow Remitting (progressive decrease in symptoms over 15 months; 27%) and Non-Remitting (persistently elevated symptoms; 17%). CBT accelerated the recovery of the Slow Remitting class but did not affect the other classes.Conclusions
The early course of PTSD symptoms is characterized by distinct and diverging response patterns that are centrally relevant to understanding the disorder and preventing its occurrence. Studies of the pathogenesis of PTSD may benefit from using clustered symptom trajectories as their dependent variables. 相似文献11.
Background
MDM2 is a major negative regulator of p53, and a single nucleotide polymorphism (SNP) in the MDM2 promoter region SNP309 has been demonstrated to be associated with an increased MDM2 expression and a significantly earlier age of onset of several tumors, including gastric cancer. Several studies were published to evaluate the association between SNP309 and gastric cancer risk. However, the results remain conflicting rather than conclusive.Objective
The aim of this study was to assess the association between the MDM2 SNP309 polymorphism and gastric risk.Methods
We performed a meta-analysis to investigate this relationship. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the association. The pooled ORs were performed for codominant model, dominant model, and recessive model, respectively.Results
Five published case-control studies, including 1,621 gastric cancer cases and 2,639 controls were identified. We found that the MDM2 SNP309 polymorphism was associated with a significantly increased risk of gastric cancer risk when all studies were pooled into the meta-analysis (GG versus TT, OR = 1.54; 95%CI = 1.04–2.29, and GG versus GT/TT, OR = 1.49, 95%CI = 1.30–1.72). Furthermore, Egger''s test did not show any evidence of publication bias (P = 0.799 for GG versus TT).Conclusion
Our results suggest that the MDM2 SNP309 polymorphism may be a low-penetrant risk factor for the development of gastric cancer. 相似文献12.
Chun-Yan Li Bo Song Ying-Yan Wang Hua Meng Shi-Bin Guo Li-Na Liu Hai-Chen Lv Qi-Jun Wu 《PloS one》2013,8(6)
Background
Various observational studies have focused on the relationship between menarcheal age and the risk of colorectal cancer (CRC). However, the association is still controversial because of inconsistent results. Therefore, we performed a meta-analysis to assess this issue from epidemiological studies.Methods
After a literature search in MEDLINE, EMBASE, and Web of Science for studies of menarcheal age and CRC risk published through the end of January 2013, we pooled the relative risks (RRs) from included studies using a fixed- or random-effects model and performed heterogeneity and publication bias analyses. All statistical tests were two-sided.Results
Eleven case-control and 11 cohort studies were eligible for inclusion in our analysis. The random-effects pooled RR for oldest versus youngest menarcheal age was 0.95 [95% confidence intervals (CIs) = 0.85–1.06], with significant heterogeneity (Q = 61.03, P<0.001, I 2 = 65.6%). When separately analyzed, case-control (RR = 0.95, 95% CI = 0.75–1.21) and cohort studies (RR = 0.97, 95% CI = 0.90–1.04) yielded similar results. Moreover, similar results were also observed among the subgroup analyses by study quality, population, exposure assessment, anatomic cancer site, subsite of colon cancer, and several potential important confounders and risk factors. There was no evidence of publication bias and significant heterogeneity between subgroups detected by meta-regression analyses.Conclusions
Findings from this meta-analysis demonstrated that menarcheal age was not associated with the risk of CRC in humans. Further studies are warranted to stratify results by the subsite of colon cancer and menopause status in the future. 相似文献13.
Background
The Brief Infant-Toddler Social and Emotional Assessment (BITSEA) is a promising questionnaire for the early detection of psychosocial problems in toddlers. The screening accuracy and clinical application were evaluated.Methods
In a community sample of 2-year-olds (N = 2060), screening accuracy of the BITSEA Problem scale was examined regarding a clinical CBCL1.5-5 Total Problem score. For the total population and subgroups by child’s gender and ethnicity Receiver Operating Characteristic (ROC) curves were calculated, and across a range of BITSEA Problem scores, sensitivity, specificity, likelihood ratio’s, diagnostic odds ratio and Youden’s index. Clinical application of the BITSEA was examined by evaluating the relation between the scale scores and the clinical decision of the child health professional.Results
The area under the ROC curve (95% confidence interval) of the Problem scale was 0.97(0.95–0.98), there were no significant differences between subgroups. The association between clinical decision and BITSEA Problem score (B = 2.5) and Competence score (B = −0.7) was significant (p<0.05).Conclusions
The results indicate that the BITSEA Problem scale has good discriminative power to differentiate children with and without psychosocial problems. Referred children had less favourable scores compared to children that were not referred. The BITSEA may be helpful in the early detection of psychosocial problems. 相似文献14.
Dulciene Maria Magalhaes Queiroz Paul R. Harris Ian R. Sanderson Henry J. Windle Marjorie M. Walker Andreia Maria Camargos Rocha Gifone Aguiar Rocha Simone Diniz Carvalho Paulo Fernando Souto Bittencourt Lucia Porto Fonseca de Castro Andrea Villagrán Carolina Serrano Dermot Kelleher Jean E. Crabtree 《PloS one》2013,8(7)
Objective
Iron deficiency (ID) and iron deficiency anaemia (IDA) are global major public health problems, particularly in developing countries. Whilst an association between H. pylori infection and ID/IDA has been proposed in the literature, currently there is no consensus. We studied the effects of H. pylori infection on ID/IDA in a cohort of children undergoing upper gastrointestinal endoscopy for upper abdominal pain in two developing and one developed country.Methods
In total 311 children (mean age 10.7±3.2 years) from Latin America - Belo Horizonte/Brazil (n = 125), Santiago/Chile (n = 105) - and London/UK (n = 81), were studied. Gastric and duodenal biopsies were obtained for evaluation of histology and H. pylori status and blood samples for parameters of ID/IDA.Results
The prevalence of H. pylori infection was 27.7% being significantly higher (p<0.001) in Latin America (35%) than in UK (7%). Multiple linear regression models revealed H. pylori infection as a significant predictor of low ferritin and haemoglobin concentrations in children from Latin-America. A negative correlation was observed between MCV (r = −0.26; p = 0.01) and MCH (r = −0.27; p = 0.01) values and the degree of antral chronic inflammation, and between MCH and the degree of corpus chronic (r = −0.29, p = 0.008) and active (r = −0.27, p = 0.002) inflammation.Conclusions
This study demonstrates that H. pylori infection in children influences the serum ferritin and haemoglobin concentrations, markers of early depletion of iron stores and anaemia respectively. 相似文献15.
Juan Chen Ye Tian Yixing Liao Shuaishuai Yang Zhuoting Li Chao He Dahong Tu Xinying Sun 《PloS one》2013,8(11)
Objective
To evaluate the effect of an improved salt-restriction spoon on the attitude of salt-restriction, the using rate of salt-restriction-spoon, the actual salt intake, and 24-hour urinary sodium excretion (24HUNa).Design
A community intervention study.Setting
Two villages in Beijing.Participants
403 local adult residents being responsible for home cooking.Intervention
Participants were randomly assigned to the intervention group or the control group. Those in the intervention group were provided with an improved salt-restriction-spoon and health education, and were informed of their actual salt intake and 24HUNa. Not any intervention was given to those in the control group.Main Outcome Measures
The scores on the variables of Health Belief Model, the using rate of salt-restriction-spoon, the actual salt intake, and 24HUNa.Analysis
Covariance analyses, Chi-square tests, Student’s t tests, and repeated measures analyses of variance.Results
After 6 months of intervention, the intervention group felt significantly less objective barriers, and got access to significantly more cues to action as compared to the control group. The using rate and the correctly using rate of salt-restriction-spoon were significantly higher in the intervention group. The daily salt intake decreased by 1.42 g in the intervention group and by 0.28 g in the control group, and repeated measures analysis of variance showed significant change over time (F = 7.044, P<0.001) and significant difference between groups by time (F = 2.589, P = 0.041). The 24HUNa decreased by 34.84 mmol in the intervention group and by 33.65 mmol in the control group, and repeated measures analysis of variance showed significant change over time (F = 14.648, P<0.001) without significant difference between groups by time (F = 0.222, P = 0.870).Conclusions
The intervention effect was acceptable, therefore, the improved salt-restriction-spoon and corresponding health education could be considered as an alternative for salt reduction strategy in China and other countries where salt intake comes mainly from home cooking. 相似文献16.
Jessica L. Barrington-Trimis Susan Searles Nielsen Susan Preston-Martin W. James Gauderman Elizabeth A. Holly Federico M. Farin Beth A. Mueller Roberta McKean-Cowdin 《PloS one》2013,8(11)
Background
A recent meta-analysis suggested an association between exposure to paternal smoking during pregnancy and childhood brain tumor risk, but no studies have evaluated whether this association differs by polymorphisms in genes that metabolize tobacco-smoke chemicals.Methods
We assessed 9 functional polymorphisms in 6 genes that affect the metabolism of polycyclic aromatic hydrocarbons (PAH) to evaluate potential interactions with parental smoking during pregnancy in a population-based case-control study of childhood brain tumors. Cases (N = 202) were ≤10 years old, diagnosed from 1984–1991 and identified in three Surveillance, Epidemiology, and End Results (SEER) registries in the western U.S. Controls in the same regions (N = 286) were frequency matched by age, sex, and study center. DNA for genotyping was obtained from archived newborn dried blood spots.Results
We found positive interaction odds ratios (ORs) for both maternal and paternal smoking during pregnancy, EPHX1 H139R, and childhood brain tumors (P interaction = 0.02; 0.10), such that children with the high-risk (greater PAH activation) genotype were at a higher risk of brain tumors relative to children with the low-risk genotype when exposed to tobacco smoke during pregnancy. A dose-response pattern for paternal smoking was observed among children with the EPHX1 H139R high-risk genotype only (ORno exposure = 1.0; OR≤3 hours/day = 1.32, 95% CI: 0.52–3.34; OR>3hours/day = 3.18, 95% CI: 0.92–11.0; P trend = 0.07).Conclusion
Parental smoking during pregnancy may be a risk factor for childhood brain tumors among genetically susceptible children who more rapidly activate PAH in tobacco smoke. 相似文献17.
Ting Wang Yang Liu Li Sima Liang Shi Zhaoming Wang Chunhui Ni Zhengdong Zhang Meilin Wang 《PloS one》2012,7(11)
Background
The -93G>A (rs1800734) polymorphism located in the promoter of mismatch repair gene, MLH1, has been identified as a low-penetrance variant for cancer risk. Many published studies have evaluated the association between the MLH1 -93G>A polymorphism and colorectal cancer (CRC) risk. However, the results remain conflicting rather than conclusive.Objective
The aim of this study was to assess the association between the MLH1 -93G>A polymorphism and the risk of CRC.Methods
To derive a more precise estimation of the association, a meta-analysis of six studies (17,791 cases and 13,782 controls) was performed. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the strength of the association. Four of these published studies were performed on subjects of known microsatellite instability (MSI) status. An additional analysis including 742 cases and 10,895 controls was used to assess the association between the MLH1 -93G>A polymorphism and the risk of MSI-CRC.Results
The overall results indicated that the variant genotypes were associated with a significantly increased risk of CRC (AG versus GG: OR = 1.06, 95% CI = 1.01–1.11; AA/AG versus GG: OR = 1.06, 95% CI = 1.01–1.11). This increased risk was also found during stratified analysis of MSI status (AA versus GG: OR = 2.52, 95% CI = 1.94–3.28; AG versus GG: OR = 1.29, 95% CI = 1.10–1.52; AA/AG versus GG: OR = 1.45, 95% CI = 1.24–1.68; AA versus AG/GG: OR = 2.29, 95% CI = 1.78–2.96). Egger’s test did not show any evidence of publication bias.Conclusion
Our results suggest that the MLH1 -93G>A polymorphism may contribute to individual susceptibility to CRC and act as a risk factor for MSI-CRC. 相似文献18.
Purpose
To evaluate intraocular lens (IOL) tilt and decentration by anterior segment optical coherence tomography (AS-OCT) using 3-dimensional (3D) reconstruction method.Design
Prospective observational case series.Participants
Thirty-nine patients (39 eyes) were included.Methods
The IOL positions of all eyes were examined by AS-OCT. Images were obtained in 4 axes (0–180 degrees, 45–225 degrees, 90–270 degrees, and 135–315 degrees) using the quadrant-scan model. The cross-sectional images were analyzed with MATLAB software.Main Outcome Measures
The angle (θ) between the reference pupillary plane and the IOL plane, the distances between the center points of the pupil circle and the IOL on the x-axis (dx) and y-axis (dy) and the spatial distance (ds) were calculated after 3D-reconstruction.Results
The mean angle (θ) between the pupillary plane and the IOL plane was 2.94±0.99 degrees. The mean IOL decentration of dx and dy was 0.32±0.26 mm and 0.40±0.27 mm, respectively. The ds of the IOL decentration was 0.56±0.31 mm. There was no significant correlation between the ocular residual astigmatism (ORA) and the tilted angle or the decentration distance. There was a significant correlation between the ORA and total astigmatism (r = 0.742, P<0.001). There was no significant correlation between the postoperative best corrected visual acuity (BCVA) and the ORA (r = 0.156; P = 0.344), total astigmatism (r = 0.012; P = 0.942), tilted angle (θ; r = 0.172; P = 0.295) or decentration distance (dx: r = 0.191, P = 0.244; dy: r = 0.253, P = 0.121; ds: r = 0.298, P = 0.065).Conclusions
AS-OCT can be used as an alternative for the analysis of IOL tilt and decentration using 3D-reconstruction. 相似文献19.
Background
The PlA2 polymorphism of glycoprotein IIIa (GPIIIa) has been previously identified as being associated with myocardial infarction (MI), but whether this represents a true association is entirely unclear due to differences in findings from different studies. We performed a meta-analysis to evaluate whether this polymorphism is a risk factor for MI.Methods
Electronic databases (MEDLINE and EMBASE) were searched for all articles evaluating genetic polymorphisms of GPIIIa. For studies where acute coronary events were recorded in association with genetic analysis, pooled odds ratios (ORs) were calculated using fixed-effects and random-effects models. The primary outcome measure was MI, and a secondary analysis was also performed for acute coronary syndromes (ACS) more generally.Findings
57 studies were eligible for statistical analysis and included 17,911 cases and 24,584 controls. Carriage of the PlA2 allele was significantly associated with MI (n = 40,692; OR 1.077, 95% CI 1.024–1.132; p = 0.004) but with significant publication bias (p = 0.040). The degree of association with MI increased with decreasing age of subjects (≤45 years old: n = 9,547; OR 1.205, 95% CI 1.067–1.360; p = 0.003) and with adjustment of data for conventional cardiovascular risk factors (n = 12,001; OR 1.240, 95% CI 1.117–1.376; p<0.001). There was a low probability of publication bias for these subgroup analyses (all p<0.05).Conclusions
The presence of significant publication bias makes it unclear whether the association between carriage of the PlA2 allele and MI is true for the total population studied. However for younger subjects, the relative absence of conventional cardiovascular risk factors results in a significant association between carriage of the PlA2 allele and MI. 相似文献20.