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31.
Genetic and environmental factors influence insulin sensitivity (IS) during one's lifetime. Actually, uterine environment may affect IS at birth and later in life. In particular, various exogenous toxic substances, coupled to a genetic predisposition, may remarkably influence the regulation of the hypothalamus–hypophysis–adrenal gland axis, and the production or the activity of insulin, cerebral incretins, pro-inflammatory cytokines, and placental hormones. Owing to this reaction against environmental injuries, fetal growth and endocrine system development may be impaired, leading to low or large birth weight, or prematurity. Reduced growth in early life has been related to insulin resistance, which can be silent for years and evident in predisposed adults. The incidence of type 2 diabetes mellitus and obesity associated with sedentary lifestyle patterns and inadequate dieting behaviors in children and adolescents has rapidly increased during the last decade.Recent evidences suggest that the Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-? (PPAR-?) gene and the angiotensin converting enzyme (ACE) I/D gene polymorphism combined with environmental factors, such as phthalates interfering with the post receptorial action of insulin, alter insulin-sensible tissues. Therefore, IS, deriving from a complex interaction between genotype and environment, may change during life and depends on previous metabolic control, which is a sort of metabolic memory. The goal for the future is preventing the complications associated with impaired IS through the control of exogenous factors and the use of drugs selectively effective on its pathogenesis.  相似文献   
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An investigation into road transport exhaust emissions in the Genoa urban area was performed by comparing the quantities of carbon monoxide (CO), nitrogen oxides (NOx), nitrogen dioxide (NO2) and particulate matter (PM) emitted by different vehicle categories with air quality measurements referred to the same pollutants. Exhaust emissions were evaluated by applying the PROGRESS (computer PROGramme for Road vehicle EmiSSions evaluation) code, developed by the Internal Combustion Engines Group of the University of Genoa, to eight different years (from 1992 to 2010), considering spark ignition and Diesel passenger cars and light duty vehicles, heavy duty vehicles and buses, motorcycles and mopeds. Changes in terms of vehicles number, mileage and total emissions are presented together with relative distributions among the various vehicle categories. By comparing 1992 and 2010 data, calculated trends show a 7% increase in the number of vehicles, with total mileage growing at a faster rate (approx. 22%); total emissions decrease considerably, by approximately 50% for NOx and PM, 70% for HC and 80% for CO, due to improvements in engines and fuels forced by the stricter European legislation and the fleet renewal, while primary NO2 emission will be very close to 1992 level, after a decrease of about 18% in 2000.Air quality was analysed by selecting traffic and background measuring stations from the monitoring network managed by the Environmental Department of the Province of Genoa: average annual concentrations of considered pollutants from 1994 to 2007 were calculated in order to obtain the relative historical trends and compare them with European public health limits and with road vehicle emissions. Though an important reduction in pollutant concentrations has been achieved as a consequence of cleaner vehicles, some difficulties in complying with present and/or future NO2 and PM10 limits are also apparent, thus requiring suitable measures to be taken by the local authorities.  相似文献   
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We analyzed polychlorobiphenyls (PCBs), perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) in the edible part of farmed sea bass reared in two fish farms in Liguria (Northern Italy). The aim was to determine the contamination levels and human exposure to these chemicals through fish consumption. Concentrations of “dioxin-like” PCBs (DL-PCBs) ranged from 0.033 to 0.759 pg ΣTEQ-PCB g−1 whole weight (w.w.) in fish farm 1 and from 0.032 to 1.60 pg ΣTEQ-PCB g−1 w.w. in fish farm 2, and the six indicators of “non-dioxin-like” (NDL-PCBs) from 0.538 to 9.33 ng Σ6PCB g−1 w.w. and from 1.62 to 27.6 ng Σ6PCB g−1 w.w. Concentrations were generally lower in farm 1 than in farm 2. One reason for this difference might be the proximity of farm 2 to the seaport of La Spezia, which could be a punctual source of pollutants influencing the contamination of the water in the farm. Principal component analysis (PCA) showed differences also in the congeners profiles for the two sites, with higher-chlorinated PCBs more abundant in farm 1, and lower-chlorinated PCBs were more abundant in farm 2. Most of the concentrations of PFOS and PFOA were below the limit of detection (LOD 0.05 ng g−1 w.w.). Only about 10% of the samples analyzed had levels slightly higher than the LOD. Assessments of exposure using these data showed that consumption of farmed fish may contribute significantly to PCBs through the diet, whereas the contribution of PFOS and PFOA seems to be low.  相似文献   
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This paper addresses the issue of risk from disasters occurring due to accidents in high-consequence technologies, e.g., nuclear and oil and gas. The focus is on the challenges posed to the representation and treatment of uncertainties in the assessment of such risk, given that the occurrence of such extreme disasters is extremely unlikely, and yet they occur. A general framework of analysis is proposed.  相似文献   
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Objective

To investigate whether perioperative fetal hemodynamic changes in twin-to-twin transfusion syndrome (TTTS) are associated with neurodevelopmental impairment (NDI) at two years.

Methods

Doppler parameters of three sonograms (day before, first day after and 1 week after laser surgery for TTTS) were assessed for correlation with neurodevelopmental outcome at two years (2008-2016). NDI was defined as: cerebral palsy, deafness, blindness, and/or a Bayley-III cognitive/motor developmental test-score > 2SD below the mean.

Results

Long-term outcome was assessed in 492 TTTS survivors. NDI was present in 5% (24/492). After adjustment for severe cerebral injury (present in 4%), associated with NDI were: middle cerebral artery peak systolic velocity (MCA-PSV) >1.5 multiples of the median (MoM) 1 day after surgery (odds ratio [OR] 4.96; 95% confidence interval [CI]: 1.17-21.05, P = .03), a change from normal umbilical artery pulsatility index (UA-PI) presurgery to UA-PI >p95 postsurgery (OR 4.19; 95% CI: 1.04-16.87, P = .04), a change from normal to MCA-PSV >1.5MoM (OR 4.75; 95% CI: 1.43-15.77, P = .01).

Conclusion

Perioperative fetal hemodynamic changes in TTTS pregnancies treated with laser are associated with poor neurodevelopmental outcome. Prospective research on the cerebrovascular response to altered hemodynamic conditions is necessary to further understand the cerebral autoregulatory capacity of the fetus in relation to neurodevelopmental outcome.  相似文献   
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Despite efforts at prevention through the use of preconception folic acid, spina bifida remains one of the most common congenital anomalies of the central nervous system that is compatible with life. It is, however, associated with a significant degree of lifelong morbidity. The development of open fetal surgery for myelomeningocele (MMC) has been a long process but one that serves as a model for how new procedures and technologies need to be properly evaluated before being brought into mainstream medical practice. Even so, risks and benefits need to be evaluated for each patient. The currently available studies have been carried out on a highly selected patient population where the fetal findings provided the maximum opportunity for benefit from prenatal closure of the MMC defect. There is the potential that as the surgery becomes more widely available, pressure will be brought to bear to perform surgery in cases where the likelihood for benefit is decreased and yet the risks are not. The only way to duplicate the results of the current studies is to follow the methodology and criteria that were used in the studies. This will mean that not every fetus with an MMC will be a candidate for in utero surgery. The balance of risk to benefit will continue to evolve as further technological advances are evaluated and more follow-up information is obtained. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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