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71.

Objective

To examine the association of placental levels of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), manganese (Mn), and chromium (Cr) with birth outcomes (birth weight, length, and head circumference, low birth weight [LBW], gestational age, preterm delivery, and small for gestational age [SGA]) in mother-child pairs from the Environment and Childhood (INMA) Project in Spain.

Methods

Metal concentrations were measured in placenta tissue samples randomly selected from five INMA cohorts. Data on birth outcomes were obtained from medical records. Associations were assessed in a sub-sample of 327 mother-infant pairs by regression models adjusted for confounding factors and for all metals simultaneously. Effect modification by sex was also evaluated.

Results

Elevated placental Cd levels (>5.79 vs. <3.30?ng/g) were associated with reduced birth weight (?111.8?g, 95%CI?=??215.6; ?8.06, p-trend?=?0.01) and length (?0.62?cm, 95%CI?=??1.20; ?0.04, p-trend?=?0.02), while a 10% increase in Cd was associated with 1.21-fold increased odds (95%CI?=?1.01; 1.43) of LBW in the global sample but with 14% lower odds (95%CI?=?0.78; 0.96) of preterm delivery in males (Pinteraction?=?0.10). Detected (vs. undetected) Hg was associated with reduced head circumference (?0.49?cm, 95%CI?=??1.00; 0.03) in females (Pinteraction?=?0.03). A 10% increase in placental Mn was associated with slight increases in gestational age (0.04 weeks, 95%CI?=?0.01; 0.07) in the global sample and in head circumference (0.05?cm, 95%CI?=??0.01; 0.10) in females (Pinteraction?=?0.03). Elevated Cr levels (>99.6 vs. <56.1?ng/g) were associated with reduced birth length (?0.68?cm, 95%CI?=??1.33; ?0.04, p-trend?=?0.02) and slightly increased gestational age (0.35 weeks, 95%CI?=??0.07; 0.77, p-trend?=?0.08) in the global sample. As and Pb were detected in few placentas (27% and 13%, respectively) and were not associated with any studied birth outcome.

Conclusions

Data suggest that in utero exposure to Cd, Hg, and Cr could adversely affect fetal growth, whereas Mn and Cr appear to have a positive effect on gestational age. Given the relatively small number of subjects, sex-specific associations should be interpreted with caution.  相似文献   
72.
In developed countries heart failure is one of the most important causes of death, followed closely by strokes and other cerebrovascular diseases. It is one of the major healthcare issues in terms of increasing number of patients, rate of hospitalizations and costs. The main aim of this paper is to present telemedicine applications for monitoring and follow-up of heart failure and to show how these systems can help reduce costs of administering heart failure. The search for e-health applications and systems in the field of telemonitoring of heart failure was pursued in IEEE Xplore, Science Direct, PubMed and Scopus systems between 2005 and the present time. This search was conducted between May and June 2015, and the articles deemed to be of most interest about treatment, prevention, self-empowerment and stabilization of patients were selected. Over 100 articles about telemonitoring of heart failure have been found in the literature reviewed since 2005, although the most interesting ones have been selected from the scientific standpoint. Many of them show that telemonitoring of patients with a high risk of heart failure is a measure that might help to reduce the risk of suffering from the disease. Following the review conducted, in can be stated that via the research articles analysed that telemonitoring systems can help to reduce the costs of administering heart failure and result in less re-hospitalization of patients.  相似文献   
73.
Resistin is a protein involved in inflammation and angiogenesis processes and may play a role in the progression of colorectal cancer (CRC). However, it remains unclear whether resistin is associated with increased mortality after CRC diagnosis. We examined pre-diagnostic serum resistin concentrations in relation to CRC-specific and all-cause mortality among 1343 incident CRC cases from the European Prospective Investigation into Cancer and Nutrition cohort. For CRC-specific mortality as the primary outcome, hazard ratios (HRs) and 95% confidence intervals (95% CI) were estimated from competing risk analyses based on cause-specific Cox proportional hazards models and further in sensitivity analyses using Fine–Gray proportional subdistribution hazards models. For all-cause mortality as the secondary outcome, Cox proportional hazards models were used. Subgroup analyses were performed by sex, tumor subsite, tumor stage, body mass index and time to CRC diagnosis. Resistin was measured on a median of 4.8 years before CRC diagnosis. During a median follow-up of 8.2 years, 474 deaths from CRC and 147 deaths from other causes were observed. Resistin concentrations were not associated with CRC-specific mortality (HRQ4vsQ1 = 0.95, 95% CI: 0.73–1.23; Ptrend = .97; and HRper doubling of resistin concentration = 1.00; 95% CI: 0.84–1.19; P = .98) or all-cause mortality. Results from competing risk (sensitivity) analysis were similar. No associations were found in any subgroup analyses. These findings suggest no association between pre-diagnostic circulating resistin concentrations and CRC-specific or all-cause mortality among persons with CRC, and the potential insignificance of resistin in CRC progression.  相似文献   
74.
The molecular hallmarks of inflammation-mediated lung carcinogenesis have not been fully clarified, mainly due to the scarcity of appropriate animal models. We have used a silica-induced multistep lung carcinogenesis model driven by chronic inflammation to study the evolution of molecular markers and genetic alterations. We analyzed markers of DNA damage response (DDR), proliferative stress, and telomeric stress: γ-H2AX, p16, p53, and TERT. Lung cancer-related epigenetic and genetic alterations, including promoter hypermethylation status of p16(CDKN2A), APC, CDH13, Rassf1, and Nore1A, as well as mutations of Tp53, epidermal growth factor receptor, K-ras, N-ras, and c-H-ras, have been also studied. Our results showed DDR pathway activation in preneoplastic lesions, in association with inducible nitric oxide synthase and p53 induction. p16 was also induced in early tumorigenic progression and was inactivated in bronchiolar dysplasias and tumors. Remarkably, lack of mutations of Ras and epidermal growth factor receptor, and a very low frequency of Tp53 mutations suggest that they are not required for tumorigenesis in this model. In contrast, epigenetic alterations in p16(CDKN2A), CDH13, and APC, but not in Rassf1 and Nore1A, were clearly observed. These data suggest the existence of a specific molecular signature of inflammation-driven lung carcinogenesis that shares some, but not all, of the molecular landmarks of chemically induced lung cancer.  相似文献   
75.
OBJECTIVE: To evaluate the appropriateness of the use of total hip joint replacements. DESIGN: Observational study of consecutive patients with a diagnosis of hip osteoarthritis and who had undergone total hip arthroplasty over a 1-year period from seven hospitals. MAIN MEASURES: The appropriateness of the use of hip replacement was judged by explicit criteria developed by a panel of experts using RAND methodology. The length of hospital stay during the admission and complications were recorded 6 months post-operatively. Patients were also surveyed 6 months after discharge to determine whether they believed they had recovered or their satisfaction with the intervention. Appropriateness results of this study were compared with a previous study performed with the same criteria 4 years previously. RESULTS: In total, 784 patients participated in the study. Indications for surgery were considered necessary in 52.2% of cases, appropriate in 21.3%, uncertain in 21.4%, and inappropriate in 5.1%. Differences were found in the rates of appropriateness exclusively from one hospital. At 6 months after discharge, differences between centres were found for the proportion of patients that reported they had recovered from surgery (range 57.7-24.8%) and in the length of hospital stay during admission (range 10-16 days). Improvement in the appropriateness rates were found for all participant hospitals during both periods. CONCLUSIONS: We identified a low percentage of inappropriate indications and differences in some outcomes between centres. Compared with previously, there has been improvement in the use of this technique, although both periods are not methodologically comparable.  相似文献   
76.
The purpose of this study was to develop a predictive model for perceived competence and to obtain an integrator evaluation of the nursing curriculum with measures of nursing self‐efficacy, general self‐efficacy, resilience, and stress among nursing students. A correlational study with nursing students (N = 265) from the degree in nursing was conducted. A factor analysis was used to test the construct validity of nursing self‐efficacy and perceived competence. The correlational and discriminant analyses evaluated the factors in the four academic levels of the degree (2016–2017) to identify the variables involved in the classification of the students in each level. The results of exploratory and confirmatory factor analyses of nursing self‐efficacy and perceived competence revealed a statistically significant good fit and consistency. Nursing self‐efficacy, general self‐efficacy, resilience, and year of the degree course predicted 34% of perceived competence scores. The discriminant function of nursing self‐efficacy, perceived competence, and resilience classified 76% of participants in the first and last years of the degree. Nursing self‐efficacy, perceived competence, and resilience increased with academic level. They help chart nursing students' progress through the curriculum.  相似文献   
77.
Obesity, a worldwide epidemic, confers increased risk for multiple serious conditions, including type 2 diabetes, cardiovascular diseases, nonalcoholic fatty liver disease and cancer. Adipose tissue is considered one of the largest endocrine organs in the body as well as an active tissue for cellular reactions and metabolic homeostasis rather than an inert tissue for energy storage. The functional pleiotropism of adipose tissue relies on its ability to synthesize and release a large number of hormones, cytokines, extracellular matrix proteins and growth and vasoactive factors, collectively termed adipokines that influence a variety of physiological and pathophysiological processes. In the obese state, excessive visceral fat accumulation causes adipose tissue dysfunctionality that strongly contributes to the onset of obesity‐related comorbidities. The mechanisms underlying adipose tissue dysfunction include adipocyte hypertrophy and hyperplasia, increased inflammation, impaired extracellular matrix remodelling and fibrosis together with an altered secretion of adipokines. This review describes how adipose tissue becomes inflamed in obesity and summarizes key players and molecular mechanisms involved in adipose inflammation.  相似文献   
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80.
BackgroundThe immunoglobulin G1 (IgG1) monoclonal antibody (MoAb) Cetuximab is active in metastatic colorectal cancer (mCRC) as first or subsequent lines of therapy. Efficacy seems restricted to KRAS wild-type tumours. IgG1 may also induce antibody dependent cell mediated citotoxicity (ADCC) by recruitment of immune effector cells. ADCC is influenced by Fc gamma receptor (FcγR) polymorphisms. We investigated the association of FcγR polymorphisms and disease control rate (DCR) in mCRC patients treated with chemotherapy plus Cetuximab.Patients and methodsTumour tissues from 106 patients were screened for KRAS codon 12 and 13 mutations using a sensitive multiplex assay (DxS, Manchester, United Kingdom). NRAS (codons: 12, 13 and 61), PI3K (exon 20) and BRAF (exon 15) were analysed by direct sequencing. Fcγ RIIa and Fcγ RIIIa polymorphisms were genotyped by TaqMan assays.ResultsDCR was significantly higher in KRAS wild-type tumours (61% versus 39%, p = 0.049). In epidermal growth factor receptor (EGFR) downstream-mutated mCRC patients, those harbouring an FcγRIIa H/H genotype had a higher DCR than alternative genotypes (67% versus 33%, p = 0.017). By multivariate analysis, FcγRIIa-131H/H remained significantly correlated with DCR (p = 0.008).ConclusionFcγR polymorphisms may play a role in the clinical efficacy of Cetuximab in EGFR downstream mutated mCRC patients. Further research into Cetuximab immune-based mechanisms in KRAS-mutated patients seems warranted.  相似文献   
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