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31.
To estimate the genetic and dietary factors influencing bone mineral density (BMD) in young adults, a total of 53 healthy volunteers (HV) (age 20.89+/-1.34), from whom informed consent was obtained, answered a questionnaire on dietary factors and had DNA from peripheral blood mononuclear cells analyzed for single nucleotide polymorphisms (SNPs) for vitamin (Vit) D receptor (VDR), estrogen receptor alpha (ERalpha), interleukin 1 receptor antagonist (IL1RA), and apolipoprotein E (ApoE) genes. Daily intakes of Vit C, fiber, soybean and related foods, and green and yellow vegetables showed a correlation with % BMD. In addition, Vit B2 as well as Vit C, and vegetables were identified as important factors for BMD by Stepwise regression analysis. Among the SNPs analyzed, the B+ type of the VDR gene tended to be associated with a lower BMD, and pp type of the ER gene digested by the PvuII enzyme in females indicated a significantly lower BMD than that in males. In addition, these SNPs were also identified by factor analysis to be associated with BMD. These results suggested that a complex array of genetic factors, such as two or more SNPs or SNPs and gender, may be important to BMD.  相似文献   
32.
The nerve gas sarin has been responsible for tragic disasters in Matsumoto city, Nagano in 1994 and in the Tokyo subway system in 1995, which was a terrorist attack against non-military citizens. These chemical weapons exposures shocked the world, and have become sources of social concern. Thereafter there were several toxic substance-evoked incidents in Japan, specifically a poisoning due to curry containing arsenite at Wakayama city and foods and drinks containing other toxic chemicals. Following these tragic events, the Japanese government started to prepare a risk and medical management system for countering chemical and biological terrorism by developing a network of nationwide highly-sophisticated analytical instruments in police research institutes and emergency hospitals. Various ministries and National Research Institutes also provide information, guidelines and treatments for chemical and biological agents. In the event of an emergency such as a mass chemical exposure or mass food poisoning, information on "when, where, who, whom, what, how" should be reported rapidly and accurately to the first responding national organizations, such as police and fire departments, health care centers, and hospitals. Pharmaceutical scientists and pharmacists have been educated and trained on the handling of toxic chemical substances as well as drugs, and thus in the case of an event, they can become advisers for risk assessment and the analysis of drugs and chemicals. Japan has experienced food- and drink-poisonings as terrorism-like attacks. Poisonings caused by the herbicide paraquat and other pesticides including organophosphate insecticides, potassium cyanate and the above-mentioned arsenite-poisoned curry food have occurred. Because of easy access to internet-aided purchases of toxic substances and the import and export of foods, we must pay attention to possible massive exposures through foods and develop emergency management measures to counter them.  相似文献   
33.
ObjectiveThis study examined whether the experience of enjoyable mealtimes at home during childhood was related to eating behaviors and subjective diet-related quality of life in adulthood.MethodsThe study used data (n = 2,936) obtained from a research program about Shokuiku (food and nutrition education) conducted by the Cabinet Office in Japan in November and December 2009. The study employed logistic regression adjusted for all predictor variables.ResultsEnjoyable eating experiences in childhood were positively associated with a balanced diet (meals with 3 dishes; odds ratio [OR]: 1.78, 95% confidence interval [CI]: 1.45-2.19), eating vegetable dishes (OR: 1.71, 95% CI: 1.37–2.12), and subjective diet-related quality of life scores (OR: 3.84, 95% CI: 3.14-4.70) in adulthood.Conclusions and ImplicationsThis study suggests that enjoyable eating experiences at home during childhood appear to promote healthy eating habits and the development of a positive diet-related quality of life in the future.  相似文献   
34.
Silica and asbestos cause pneumoconioses known as silicosis and asbestosis, respectively, that are each characterized by progressive pulmonary fibrosis. On the other hand, silicosis patients often suffer from a type of immunological dysregulation that gives rise to autoimmunity. These epidemiological findings suggest that silica may affect the immune system in humans. In addition, as asbestos itself is a mineral silicate, it may possess generalized immunotoxicological effects similar to those associated with silica particles. Because asbestos-exposed patients are well-known to often develop malignant diseases such as lung cancer and mesothelioma, one silica-like dysregulatory outcome that needs to be considered (apart from autoimmunity) is an alteration in host tumor immunity. In this review, the immunotoxicological effects of both silica and asbestos are presented and discussed in terms of immune system dysregulation as manifested by the onset of autoimmunity or alterations in host tumor immunity.  相似文献   
35.

Background

The isotemporal substitution (IS) approach can be used to assess the effect of replacing one activity with the equal duration of another activity on relevant outcomes. This study examined the associations of objectively assessed sedentary behavior (SB) and physical activity (PA) with health-related quality of life (HRQOL) in older Japanese adults, using the IS approach.

Methods

Participants were 287 older Japanese adults (aged 65–84?years) who wore accelerometers for at least 7 days. We calculated the average daily time spent in SB (≤1.5 METs); light-intensity PA (LPA: >?1.5 to <?3.0 METs); and moderate- to vigorous-intensity PA (MVPA: ≥3.0 METs) per day. HRQOL was assessed using the Medical Outcomes Survey Short Form-8 questionnaire.

Results

The IS models showed replacing SB or LPA with MVPA to be significantly associated with better physical component summary scores. Replacing SB with MVPA was marginally associated with better mental component summary scores.

Conclusion

These findings indicate that replacing SB with the same amount of MVPA may contribute to better physical HRQOL in older adults.
  相似文献   
36.
Since delusional disorder is characterized by mono-symptomatic paranoid symptoms, it can be a good clinical model for investigating the dopaminergic mechanism responsible for paranoid symptoms. We examined neuroleptic responses, plasma homovanillic acid (pHVA) and genes of the dopamine receptor (DR) and its synthesizing enzyme (tyrosine hydroxylase: TH) in patients with delusional disorder and compared them with those of schizophrenic patients and healthy controls. RESULTS: (1) A relatively small dose of haloperidol was more effective for delusional disorder than for schizophrenia. (2) The pretreatment level of pHVA was higher in patients with persecution-type, but not in those with jealousy-type delusional disorder, compared with age- and sex-matched controls. This increased pHVA level was decreased eight weeks after successful haloperidol treatment. (3) The genotype frequency of the DRD2 gene Ser311Cys was significantly higher in patients with persecution-type delusional disorder (21%), compared with schizophrenic patients (6%) or controls (6%). (4) Patients homozygous for the DRD3 gene Ser9Ser had higher pretreatment levels of pHVA than those heterozygous for Ser9Gly. (v) A significant positive correlation was found between the polymorphic (TCAT)(n) repeat in the first intron of the TH gene and pretreatment levels of pHVA in delusional disorder. We suggest that delusional disorder, especially the persecution-type, includes a "dopamine psychosis," and that polymorphism of the DRD2, DRD3 and/or TH gene is part of the genetic basis underlying the hyperdopaminergic state that produces paranoid symptoms. Further studies on a large sample size are required.  相似文献   
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Some major metabolic pathways of 3,4-methylenedioxymethamphetamine (MDMA) have been shown to be dependent on cytochrome P450 (CYP) isozymes by in vitro studies. The aim of this study was to clarify the roles of these CYP enzymes for in vivo metabolism of MDMA with respect to two pathways using rats: N-demethylation of MDMA to 3,4-methylenedioxyamphetamine (MDA) and O-demethylenation of MDMA to 3,4-dihydroxymethamphetamine (HHMA)followed by O-methylation to 4-hydroxy-3-methoxymethamphetamine (HMMA). Rats were pretreated with phenobarbital (PB, 80 mg/kg i.p.) or β-naphthoflavone (BNF, 80 mg/kg i.p.) once a day for 3 days before administration of MDMA (10 mg/kg i.p.). Metabolic changes were monitored by measuring the urinary excretion of MDMA and its metabolites. Twenty-four hours after MDMA administration, MDA in rat urine was significantly decreased by 43% and 70%, and HMMA was significantly increased by 33% and 64% in urine samples from PB-pretreated and BNF-pretreated rats, respectively, as compared with the control values. Testosterone 6β-hydroxylase (CYP3A), pentoxyresorufin O-dealkylase (CYP2B1), ethoxyresorufin O-deethylase (CYP1A1), and methoxyresorufin O-demethylase (CYP1A2) activities were increased 2–6 fold in both PB-pretreated and BNF-pretreated rat liver microsomes sampled at 24 h after MDMA administration as compared with the control values. These results suggest that PB-induced and BNF-induced CYP enzymes have inhibitory effects on N-demethylation of MDMA to MDA in vivo in rats. If HHMA is the precursor of HMMA in rats, there is a possibility that the O-demethylenation of MDMA to HHMA is increased by the induced CYP enzymes. The decreased urinary concentration of MDMA and very low percent recoveries of MDA, HMMA, and (4-hydroxy-3-methoxyphenyl)acetone (HMPA) in the inducer-pretreated groups suggest that other metabolic pathways of MDMA exist and are activated under the present experimental conditions.  相似文献   
40.
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