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31.
The involvement of reactive oxygen species (ROS) and oxidative stress in pediatric diseases is an important concern, but oxidative stress status in healthy young subjects and appropriate methods for its measurement remain unclear. This study evaluated a comprehensive set of urinary biomarkers for oxidative stress in healthy children, adolescents and young adults. Results show that urinary excretion of acrolein-lysine, 8-hydroxy-2'-deoxyguanosine (8-OHdG), nitrite/nitrate and pentosidine were highest in the youngest subjects and decreased to constant levels by early adolescence. Urinary acrolein-lysine, 8-OHdG, nitrite/nitrate and pentosidine showed significant inverse correlations with age, but pyrraline did not change significantly with age. No significant differences in biomarkers were apparent between males and females. Younger subjects grow rapidly and sustain immune activation, and are probably exposed to high concentrations of ROS and nitric oxide. Consequently, they are more vulnerable to oxidation of lipids, proteins, DNA and carbohydrates. Normal reported values in this study are a basis for future studies of disease mechanisms involving oxidative stress and for future trials using antioxidant therapies for oxidative stress-related diseases in the pediatric field.  相似文献   
32.
Platelet serotonin concentration in alcoholic subjects   总被引:1,自引:0,他引:1  
Serotonin (5-hydroxytryptamine, 5-HT) is assumed to play a role in the pathophysiology of different psychiatric disorders including alcoholism. Since platelets and central serotonergic synaptosomes share similar pharmacodynamics of 5-HT, this study determined platelet 5-HT concentration in 148 male and 42 female drug-free subjects with alcohol dependency, according to the DSM-IV criteria, and in sex-and age-matched controls. Male and female alcoholics had significantly lower platelet 5-HT concentration than 110 male and 123 female healthy controls. Sex differences, i.e. higher platelet 5-HT concentration in men than in women, were found both in healthy and alcoholic subjects. Platelet 5-HT concentration differed significantly in male and female alcoholic subjects with or without different psychiatric comorbidities. Platelet 5-HT concentration was higher in male alcoholics with comorbid posttraumatic stress disorder (PTSD) than in male alcoholics with comorbid anxious-depressive disorder, or depression, or male alcoholics without any psychiatric comorbidities. Comorbid depression in female alcoholics slightly elevated platelet 5-HT levels but these values were still reduced compared to values in healthy women. Smoking status did not affect platelet 5-HT concentration either in healthy or in alcoholic subjects. The data from our study show sex differences, and reduced platelet 5-HT values, regardless of the nicotine dependence, in the large groups of male and female alcoholic subjects. Among male alcoholics the presence of comorbid PTSD partly normalized the decreased platelet 5-HT values. The results of the present study support the hypothesis that alterations in 5-HT system might be related to alcoholism.  相似文献   
33.
The aim of this study was to evaluate the effect of magnesium (Mg) loading (10.0 mg Mg/kg body wt) and daily Mg supplements (5.0 mg Mg/kg body wt) on Mg deficiency shown by increased and not by decreased serum Mg concentration during hypokinesia (decreased km number/d). The studies were done during 30 d of prehypokinesia and 364 d of hypokinesia (HK) periods. Forty endurance-trained volunteers aged 22–26 yr with a peak VO2 max of 66.3 mL·kg−1 min−1 and with an average 15.0 km/d running distance were chose as subjects. They were equally divided into four groups:
1.  Unsupplemented ambulatory control subjects (UACS).
2.  Unsupplemented hypokinetic subjects (UHKS).
3.  Supplemented hypokinetic subjects (SHKS).
4.  Supplemented ambulatory control subjects (SACS).
The SHKS and SACS groups took daily 5.0 mg elemental Mg/kg body wt and subjected to Mg loading (10.0 mg Mg/kg body wt). Both the SHKS and UHKS groups were maintained under an average running distance of 4.7 km/d, whereas the SACS and UACS groups did not experience any modifications to their normal training routines and diets. During the prehypokinetic and hypokinetic periods, excretion of Mg in feces and urine, concentration of Mg in serum, and Mg balance were measured. urinary and serum sodium (Na), potassium (K), and calcium (Ca) were also determined. In both SHKS and UHKS groups, fecal Mg loss, urinary excretion of electrolytes, and serum concentrations of electrolytes increased significantly (p≤0.05) when compared with the SACS and UACS groups. During Mg loading tests, urinary and fecal Mg excretion was also greater in the SHKS and UHKS groups than in the SACS and UACS groups. Throughout the study, Mg balance was negative in the SHKS and UHKS groups, whereas in the SACS and UACS groups, Mg balance was positive. It was concluded that significant losses of Mg occurred in the presence of negative Mg balance and Mg deficiency in endurance-trained subjects during prolonged exposure to HK, daily mg supplements, and Mg loading tests. This suggests that Mg is not entering or being retaining by the bones and cells of many tissues where most Mg is deposited normally, resulting in Mg deficiency as was shown by the increased serum Mg concentration.  相似文献   
34.
The Eco-Indicator 98 project aims at a complete revision of the Eco-Indicator 95 methodology. Like its predecessor, the target is to develop single scores for designers. The method now includes resources and land use. Important improvements are: the use of fate analysis, the much better definition of the damage categories concerned with human health and ecosystem health, using the PAF (Potentially Affected Fraction) and DALY (Disability Adjusted Life Years) concept, and a completely new approach to modelling resources and land use. Perhaps the most fundamental improvement is the management system for value choices. The result of this management system is that there will be three instead of one indicator. Each version is based on a different cultural perspective. The method should be updated continuously. It is proposed to set up an independent organisation to guide this future development.  相似文献   
35.
We have previously shown that short-lasting reduction of cerebral blood flow by bilateral clamping of carotid arteries (BCCA) results in long-lasting increase in regional GABA concentration and decrease in seizure susceptibility in rats. In the present experiments, the effect of BCCA on GABA turnover and the enzymes involved in GABA synthesis and degradation were studied in rats. Regional GABA turnover was measured by means of GABA accumulation induced by the GABA-transaminase (GABA-T) inhibitor aminooxyacetic acid (AOAA). Fourteen days after BCCA, GABA turnover was significantly increased in hippocampus, substantia nigra and cortex, but not different from sham-operated controls in several other brain regions, including striatum, hypothalamus and cerebellum. The activity of glutamate decarboxylase (GAD) measured ex vivo did not show any changes in investigated structures, while the activity of GABA-T was slightly increased in hippocampus. The increased GABA turnover in some brain regions may explain our previous findings of increased GABA content in these brain regions and decreased sensitivity of BCCA treated animals to the GABAA-receptor antagonist bicuculline.  相似文献   
36.

1. 1. One hundred and forty-five thermal-sensation tests by subjects were performed in unhomogeneous thermal environments and the whole body and the lower leg thermal-sensations were discriminated with physical data of the thermal environments using the discrimination analysis and the expanded theory of quantification II which is able to deal with data including quantitative continuous-variables and qualitative category-variables simultaneously.

2. 2. The discrimination of the whole-body thermal-sensations on the basis of the local-body thermal sensations was also done.

3. 3. As a result, it is shown that the discrimination analysis and the expanded theory of quantification II are able to discriminate the thermal sensation in unhomogeneous environments.

Author Keywords: Thermal sensation; theory of quantification II; unhomogeneous thermal environments; subjects  相似文献   

37.
Elemental concentrations in head hair and blood (whole-blood, erythrocytes and plasma) of 28 Nigerian subjects were determined using instrumental neutron activation analysis (INAA) and proton-induced X-ray emission (PIXE) techniques. Correlations found between different elements in hair and blood are reported. Hair levels of both zinc and chlorine were found to be significantly correlated with their levels in erythrocytes.  相似文献   
38.
Children are not little adults. They have unique patterns of environmental exposure and developmentally determined susceptibilities that increase their risk of disease following toxic environmental exposure. Evidence is accumulating that children's exposure to toxic chemicals in the environment is contributing to changing patterns of paediatric disease.  相似文献   
39.
Aquatic ecosystems are indispensable for life on earth and yet despite their essential function and service roles, marine and freshwater biomes are facing unprecedented threats from both traditional and emerging anthropogenic stressors. The resultant species and ecosystem-level threat severity requires an urgent response from the conservation community. With their care facilities, veterinary and conservation breeding expertise, reintroduction and restoration, and public communication reach, stand-alone aquariums and zoos holding aquatic taxa have great collective potential to help address the current biodiversity crisis, which is now greater in freshwater than land habitats. However, uncertainty regarding the number of species kept in such facilities hinders assessment of their conservation value. Here we analyzed, standardized and shared data of zoological institution members of Species360, for fish and Anthozoa species (i.e. Actinopterygii, Elasmobranchii, Holocephali, Myxini, Sarcopterygii and Anthozoa). To assess the conservation potential of populations held in these institutions, we cross-referenced the Species360 records with the following conservation schemes: the Convention on the International Trade of Endangered Species of Fauna and Flora (CITES), the IUCN Red List of Threatened species, climate change vulnerability, Evolutionary Distinct and Globally Endangered (EDGE) and The Alliance for Zero Extinction (AZE). We found that aquariums hold four of the six fish species listed by the IUCN Red List as ‘Extinct in the Wild’, 31% of Anthozoa species listed by Foden et al. (2013) as vulnerable to climate change, 19 out of the 111 Anthozoa EDGE species, and none of the species prioritized by the AZE. However, it is very likely that significant additional species of high conservation value are held in aquariums that do not manage their records in standardized, sharable platforms such as Species360. Our study highlights both the great value of aquarium and zoo collections for addressing the aquatic biodiversity crisis, as well as the importance that they maintain comprehensive, standardised, globally-shared taxonomic data.  相似文献   
40.
Genetic diversity and differentiation were analyzed in 11 populations of Magnolia stellata (Sieb. and Zucc.) Maxim. (Magnoliaceae) in the Tokai district, Japan. Variation at four nuclear microsatellite (nSSR) loci was examined, three chloroplast microsatellite (cpSSR) markers were developed and 13 haplotypes identified. The 11 populations were divided into three groups (A, B and C). Each population within the group was separated less than 40 km. Group B harbored the highest gene diversity (H) and allelic richness (Ar) for nSSR (H=0.74 and Ar=8.02). Group C had the highest diversity of chloroplast haplotypes (H=0.79 and Ar=6.8): 2.5 times more haplotypes than the other groups. Each population contributed differently to the total diversity, with respect to nSSR and cpSSR. AMOVA revealed that 58% of haplotypic and 15% of nSSR variation was partitioned among populations within groups. A Mantel test revealed significant correlations between population pairwise geographic ln(distance) and FST/(1−FST) for both nSSR (r=0.479; P=0.001) and cpSSR (r=0.230; P=0.040). Dendrograms of populations for nSSR, based on Nei’s genetic distance, were constructed using UPGMA and the neighbor-joining method. These results suggest that populations in group C have diverged from the other populations, while those in group B are similar to each other. For group B, fragmentation between populations should be avoided in order to maintain gene flow. For group C, the uniqueness of each population should be given the highest priority when planning genetic conservation measures for the species.  相似文献   
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