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1.
This Special Issue aims to examine the crucial role of nutritional status starting from pregnancy in modulating fetal, neonatal and infant growth and metabolic pathways, with potential long-term impacts on adult health. Poor maternal nutritional conditions in the earliest stages of life during fetal development and early life may induce both short-term and longer lasting effects; in particular, an increased risk of noncommunicable diseases (NCDs) and other chronic diseases such as obesity, which itself is a major risk factor for NCDs, is observed over the lifespan. Poor maternal nutrition affects the fetal developmental schedule, leading to irreversible changes and slowdown in growth. The fetus limits its size to conserve the little energy available for cardiac functions and neuronal development. The organism will retain memory of the early insult, and the adaptive response will result in pathology later on. Epigenetics may contribute to disease manifestation affecting developmental programming. After birth, even though there is a limited evidence base suggesting a relationship between breastfeeding, timing and type of foods used in weaning with disease later in life, nutritional surveillance is also mandatory in infants in the first year of life. We will explore the latest findings on nutrition in early life and term and preterm babies, as well as the role of malnutrition in the short- and long-term impact over the lifespan. Focusing on nutritional interventions represents part of an integrated life-cycle approach to prevent communicable and non-communicable diseases.  相似文献   
2.

Background

Long-chain polyunsaturated fatty acids (LC-PUFA), particularly docosahexaenoic acid (DHA) and arachidonic acid, are, respectively, n-3 and n-6 family members and play an important role in fetal and infant growth and development. Pregnancy and lactation impose special nutritional needs for the mother-fetus situation. Since the LC-PUFA required by the fetus is supplied by preferential placental transfer of preformed LC-PUFA rather than their precursor, it has been hypothesized that additional maternal supply of LC-PUFA, especially DHA, during pregnancy may improve maternal and infant outcomes.

Aim

To summarize evidences of the effect of n-3 LC-PUFA intake during pregnancy and lactation on maternal and infant outcomes in order to offer a comprehensive view of this issue that should be useful for clinical practice.

Results

Maternal n-3 LC-PUFA supplementation may reduce risk for early preterm birth >34 weeks and seems very promising for primary allergy prevention during childhood. On the contrary, there are not sufficient data proving that the consumption of oils rich in n-3 LC-PUFA during pregnancy optimizes child’s visual and neurodevelopment and reduces the risk for preeclampsia and perinatal depression; the implications of these findings remain to be elucidated.

Conclusion

The implications of n-3 LC-PUFA supplementation on fetal development, maternal outcomes and later infant growth is worth being elucidated and is promising in its potential for a positive impact on fetal and maternal outcomes.  相似文献   
3.
Welders are exposed to high concentrations of nanoparticles. Compared to larger particles, nanoparticles have been associated with more toxic effects at the cellular level, including the generation of more reactive oxygen species activity. Current methods for welding-fume aerosol exposures do not differentiate between the nano-fraction and the larger particles. The objectives of this work are to establish a method to estimate the respiratory deposition of the nano-fraction of selected metals in welding fumes and test this method in a laboratory setting. Manganese (Mn), Nickel (Ni), Chromium (Cr), and hexavalent chromium (Cr(VI)) are commonly found in welding fume aerosols and have been linked with severe adverse health outcomes. Inductively coupled plasma mass spectrometry (ICP-MS) and ion chromatography (IC) were evaluated as methods for analyzing the content of Mn, Ni, Cr, and Cr(VI) nanoparticles in welding fumes collected with nanoparticle respiratory deposition (NRD) samplers. NRD samplers collect nanoparticles at deposition efficiencies that closely resemble physiological deposition in the respiratory tract. The limits of detection (LODs) and quantitation (LOQs) for ICP-MS and IC were determined analytically. Mild and stainless steel welding fumes generated with a robotic welder were collected with NRD samplers inside a chamber. LODs (LOQs) for Mn, Ni, Cr, and Cr(VI) were 1.3 μg (4.43 μg), 0.4 μg (1.14 μg), 1.1 μg (3.33 μg), and 0.4 μg (1.42 μg), respectively. Recovery of spiked samples and certified welding fume reference material was greater than 95%. When testing the method, the average percentage of total mass concentrations collected by the NRD samplers was ~30% for Mn, ~50% for Cr, and ~60% for Ni, indicating that a large fraction of the metals may lie in the nanoparticle fraction. This knowledge is critical to the development of toxicological studies aimed at finding links between exposure to welding fume nanoparticles and adverse health effects. Future work will involve the validation of the method in workplace settings.

[Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: Digestion, extraction, and analysis procedures for nylon mesh screens.]  相似文献   

4.

Background

The Immuknow assay (IKA; Cylex) is a T-cell immune function assay that evaluates immunoreactivity in immunocompromised patients. The aim of this study was to analyze IKA values in a cohort of kidney transplantation (KT) recipients to investigate correlations between single–time point low IKA values and their trend over time with cytomegalovirus (CMV) or BK virus (BKV) reactivation.

Methods

A total of 118 adult patients receiving deceased-donor KT were enrolled (55.6 ± 11.9 years old; 79 [66.9%] male). IKA CMV and BKV viremia determinations and were performed at months 1, 3, and 6 after surgery.

Results

Overall, 272 IKA determinations were performed: IKA values significantly decreased from month 1 (422 ± 184 ng/mL) to month 3 (330 ± 159 ng/mL; P < .001) and from month 3 to month 6 (300 ± 128 ng/mL; P = .030). IKA values did not correlate with renal function or viral reactivation at any time. However, patients with either CMV or BKV viremia had a trend to higher IKA values at month 1 and lower IKA values at month 6, even if the difference did not reach a statistical significance (P = .115).

Conclusions

Our study suggests that presence of low immunologic reactivity (IKA <225 ng/mL) is not associated with an increased risk of CMV and BKV reactivation over the 1st 6 months after KT. However, a trend to a more pronounced drop in IKA values over time was observed in patients with viral reactivation. These preliminary results suggests that drop in IKA values within the 1st post-KT months, unlike single–time point immune function assay, may predict the risk of opportunistic viral infections.  相似文献   
5.
6.
Chlorpyrifos inhalation, dermal exposure and working practices of 28 pesticide applicators in Western Australia were assessed during a series of single property applications of a 0.5% (n=2) or 1% (n=26) concentration of active ingredient in water solution. Deposition on new cotton gloves worn beneath applicators' usual protective gloves was 2.4 (range 0.12-86.1) mg h(-1). Median deposition of chlorpyrifos onto a new cotton overall worn over other clothing (24 sections removed, corrected for body proportions) was 11.1 (range 0.2-41.9) mg h(-1). Deposition onto seven patches taped to the applicators' skin was 0.04 (range 0.01-4.7) mg h(-1). Inhalation concentration was 5.7 (range 0.7-219) microg m(-3) time weighted average. In one group of 17 applicators' applying to existing properties, breathing zone air concentration correlated (P<0.05) with ambient air temperature (15-38 degrees C). The questionnaire results (29 respondents) indicated applicators' practices led to increased exposure, in particular concerning poor usage and condition of protective equipment and a high frequency of splashes and spills onto the body. Prevention of deposition on clothing, in particular on the lower body is suggested, as well as improved working practices.  相似文献   
7.
This article reviews Western dietary attitudes and lifestyle choices by identifying the environmental, social and personal factors that determine said attitudes and choices. Environmental factors exert a major influence on, and complicate, dietary behavior, primarily by facilitating the consumption of meals away from home and by minimizing time dedicated to meal preparation and consumption. Social factors, from mass media to advertising and cultural traditions, also influence food intake, to an extent that is still underestimated. Ignorance of the real influence of environment and society on food choices could well blind consumers to the real significance of such choices. Accordingly, this review discusses differing aspects of emerging dietary trends and/or philosophies, and underlines their potentially harmful influence on health. Western countries are increasingly witnessing a dichotomy between the findings of nutritional science and the choices that dietary trends propose and impose. Coinciding with the obesity epidemic and the spread of other food-related diseases, this dichotomy calls for the development of effective preventive strategies.  相似文献   
8.
Information about folate intake among low-income women of childbearing age remains limited. This report presents results from a cross-sectional study of folate intake and food-related behaviors in a sample of low-income, nonpregnant women of childbearing age in California. One hundred fifty-seven nonpregnant, low-income (相似文献   
9.
10.
Incorporation of a nitric oxide (NO)-releasing moiety in aspirin can overcome its gastric side effects.We investigated the NO-release patterns and antiplatelet effects of novel furoxan derivatives of aspirin (B8 and B7) in comparison to existing antiplatelet agents. Cyclooxygenase (COX) activity was investigated in purified enzyme using an electron paramagnetic resonance-based technique. Concentration-response curves for antiplatelet agents +/- the soluble guanylate cyclase inhibitor, ODQ (50 microM) were generated in platelet-rich plasma (PRP) and washed platelets (WP) activated with collagen using turbidometric aggregometry. NO was detected using an isolated NO electrode. The furoxan derivatives of aspirin (B8, B7) and their NO-free furazan equivalents (B16, B15; all 100 microM) significantly inhibited COX activity (P < 0.01; n = 6) in vitro and caused aspirin-independent, cGMP-dependent inhibition of collagen-induced platelet aggregation in WP. B8 was more potent than B7 (PRP IC(50) = 0.62 +/- 0.1 microM for B8; 400 +/- 89 microM for B7; P < 0.0001. WP IC(50)s = 0.6 +/- 0.1 and 62 +/- 10 microM, respectively). The NO-free furazan counterparts were less potent antiplatelet agents (WP IC(50)s = 54 +/- 3 microM and 62 +/- 10 microM, respectively; P < 0.0001, B8 vs B16). Of the hybrids investigated, only B8 retained antiplatelet activity in PRP.NO release from furoxan-aspirin hybrids was undetectable in buffer alone, but was accelerated in the presence of either plasma or plasma components, albumin (4%), glutathione (GSH; 3 microM) and ascorbate (50 microM), the effects of which were additive for B7 but not B8. NO generation from furoxans was greatly enhanced by platelet extract, an effect that could largely be explained by the synergistic effect of intracellular concentrations of GSH (3 mM) and ascorbate (1 mM). We conclude that the decomposition of furoxan-aspirin hybrids to generate biologically active NO is catalysed by endogenous agents which may instil a potential for primarily intracellular delivery of NO. The blunting of the aspirin effects of furoxan hybrids is likely to be due to loss of the acetyl moiety in plasma; the observed antiplatelet effects are thereby primarily mediated via NO release. Compounds of this class might represent a novel means of inhibiting platelet aggregation by a combination of NO generation and COX inhibition.  相似文献   
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