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71.
The mechanism of the abnormal increase in extracellular glutamate concentration in the hippocampus induced with 100 mM KCl in zinc deficiency is unknown. In the present study, the changes in glutamate release (exocytosis) and GLT-1, a glial glutamate transporter, expression were studied in young rats fed a zinc-deficient diet for 4 weeks. Exocytosis at mossy fiber boutons was enhanced as reported previously and GLT-1 protein was increased in the hippocampus. The enhanced exocytosis is thought to increase extracellular glutamate concentration. However, the basal concentration of extracellular glutamate in the hippocampus was not increased by zinc deficiency, suggesting that GLT-1 protein increased serves to maintain the basal concentration of extracellular glutamate. The enhanced exocytosis was attenuated in the presence of 100 μM ZnCl2, which attenuated the abnormal increase in extracellular glutamate induced with high K+ in zinc deficiency. The present study indicates that zinc attenuates abnormal glutamate release in zinc deficiency. The enhanced exocytosis was also attenuated in slices from zinc-deficient rats administered Yokukansan, a herbal medicine, in which the abnormal increase in extracellular glutamate induced with high K+ was attenuated. It is likely that Yokukansan is useful for prevention or cure of abnormal glutamate release. The enhanced exocytosis in zinc deficiency is a possible mechanism on abnormal increase in extracellular glutamate in the hippocampus induced with high K+.  相似文献   
72.
Barnes S  Prasain JK  Wang CC  Moore DR 《Life sciences》2006,78(18):2054-2059
Specific and quantitative analyses of the bioactive components and their metabolites in body fluids are essential to assess the interaction between groups of compounds in dietary supplements and preparations of psychoactives. Reverse-phase LC separations combined with tandem mass spectrometry provide the necessary specificity and sensitivity. In this paper, applications of these methods are described for the analysis of isoflavones, salvinorin A, synephrine isomers and their metabolites in serum, urine and aqueous humor.  相似文献   
73.
We determined the concentrations of Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn in dietary supplements of marine origin. Four supplement categories were studied; algae, coral, krill, and shark cartilage. A direct mercury analyzer was used for Hg determinations while acid digestions and ICP-AES were used for Cr analysis and ICP-MS for the other trace metals. Algae are the supplements showing the highest concentrations of Pb, Cr, and Ni with respective means of 1.6 mg Pb/kg dry weight (d.w.), 3.2 Cr mg/kg d.w., and 8.0 mg Ni/kg d.w. Krill supplements have the highest levels of Cd, Cu, and Zn with 0.65 mg Cd/kg d.w., 63 mg Cu/kg d.w., and 50 mg Zn/kg d.w., respectively. Shark cartilage supplements show the highest levels of Hg and Co with mean concentrations of 160 μg Hg/kg d.w. and 73 ± 51 μg Co/kg d.w., respectively. No samples in our study exceeded the provisional tolerable daily intakes set by Health Canada, the joint committee of the World Health Organization/Food and Agricultural Organization, or the U.S. Environmental Protection Agency. Nevertheless, Ni and Pb in algae and Hg in shark cartilage may end up contributing to a very significant portion of the allowable daily intake—leaving little room for normal intake through food consumption and other exposure pathways.  相似文献   
74.
The use of dietary supplements has grown dramatically in the last decade. A large number of dietary and herbal supplements escape regulatory and quality control; components of these preparations are poisonous and may contain, among other toxins, heavy metals. Uncontrolled use of dietary and herbal supplements by special populations, such as the military, may therefore pose a health risk. Clinical symptoms are not always properly attributed to dietary supplements; patients often do not mention supplement use to their health care provider. Therefore, a health risk estimate is hard to make on either the individual or the population level. The literature on this issue was reviewed and discussed in the light of a representative clinical-chemical case study. This case study was performed on a host of preparations that were used by one single individual in the military. Both essential (chromium, copper, zinc, and iron) and poisonous (arsenic, lead, and nickel) trace elements were determined using inductively coupled plasma combined with optical emission spectrometry (ICP-OES) or with mass spectrometry (ICP-MS). Arsenic and lead were detected at exposure levels associated with health risks. These health risks were detected predominantly in hormone-containing supplements and the herbs and botanicals used for performance enhancement. To the extent that this is a representative sample, there is an underestimation of supplement use and supplement risk in the US military, if not in the general population. Since clinical symptoms may be attributed to other causes and, unless patients are specifically asked, health care providers may not be aware of their patients' use of dietary supplements, a strong support of laboratory diagnostics, such as a toxicological screening of blood or urine, is required. In addition, screening of the preparations themselves may be advised.  相似文献   
75.
目的:探讨中药熏蒸对经挂线引流术后肛瘘患者血清免疫球蛋白水平及预后的影响。方法:收集我院治疗的94例肛瘘患者,随机分为实验组和对照组,每组47例。所有患者行肛瘘挂线术,对照组患者术后采用左氧氟沙星注射液治疗,实验组患者在对照组基础上给予中药熏洗治疗。观察并比较两组患者治疗前后血清IgA及IgG水平,疼痛持续时间及恢复时间以及临床疗效。结果:与治疗前相比,两组患者治疗后血清IgA及IgG水平均下降,差异具有统计学意义(P0.05);与对照组相比,实验组患者治疗后血清IgA及IgG水平较低,差异具有统计学意义(P0.05);实验组患者疼痛持续时间及恢复时间均少于对照组,差异具有统计学意义(P0.05);实验组临床治疗有效率高于对照组,差异具有统计学意义(P0.05)。结论:中药熏蒸能够降低经挂线引流术后肛瘘患者血清IgA及IgG水平,缩短术后疼痛时间,促进术后康复,临床疗效较好。  相似文献   
76.
Objective : Few weight loss supplements are clinically tested for efficacy, yet their proliferation continues. Chitosan‐based supplements are sold as fat trappers and fat magnets. They purportedly block fat absorption and cause weight loss without food restriction. We quantified the in vivo effect of a chitosan product on fat absorption. Research Methods and Procedures : Participants (n = 15) consumed five meals per day for 12 days. Energy intake was not restricted. Participants consumed no supplements during a 4‐day control period and two capsules five times per day (4.5 g chitosan/d), 30 minutes before each meal, during a 4‐day supplement period. All feces were collected from days 2 to 12. Oral charcoal markers permitted division of the feces into two periods. The two fecal pools were analyzed for fat content. Results : Participants were male, 26.3 ± 5.9 years old, BMI of 25.6 ± 2.3 kg/m2. Subjects consumed 133 ± 23 g of fat/d and 12.91 ± 1.79 MJ/d (3084 ± 427 kcal/d). Individual meals averaged 26.3 ± 9.3 g of fat. With chitosan supplementation at 10 capsules/day, fecal fat excretion increased by 1.1 ± 1.8 g/d (p = 0.02), from 6.1 ± 1.2 to 7.2 ± 1.8 g/d. Discussion : The effect of chitosan on fat absorption is clinically negligible. Far from being a fat trapper, at 0.11 ± 0.18 g of fat trapped per 0.45‐g capsule or 1.1 g (9.9 kcal) fat trapped per day, this product would have no significant effect on energy balance. The fat trapping claims associated with chitosan are unsubstantiated.  相似文献   
77.
Nowadays, there is a constant increase of health products (food supplements, medical devices and so on), in the market, despite the crisis that involves a lot of nations at the international level. The plants and their derivatives are present in high percentage in these products and moreover people usually have great trust in plants and in natural products in general. The above-mentioned products are available in the market in the form of tablets, pills, lozenges, syrups and other forms that supplement our diet (food or dietary supplements) or act with a therapeutic effect (herbal medicines). In Italy, about 50% of the sold products contain plants and/or plant extracts, better known as botanicals according to the European Food Safety Authority settlement. It is therefore understandable how the botanicals adulteration and/or the sophistication can heavily weigh on the quality of the finished products, not only from an economic point of view but also in guaranteeing the safety of consumers.  相似文献   
78.
Hyperuricemia is defined as a metabolic abnormality that occurs when serum uric acid (UA) level is abnormally high in the body. We previously reported that A. longiloba possesses various important phytochemicals and in vitro xanthine oxidase activity. Despite A. longiloba ethnomedicinal benefits, its toxicity and anti-hyperuricemic effects have not been reported. The present study was carried out to ensure the safety and investigate the anti-hyperuricemic effects of A. longiloba fruit and petiole ethanolic extracts on rats. In the acute toxicity study, extracts were orally administered at a dose of 2000 mg/kg bodyweight and closely monitored for 2-week for any toxicity effects. The rats were then sacrificed and samples were collected and analyzed for hematological, biochemical, and histopathological parameters. The anti-hyperuricemic effect of A. longiloba fruit or petiole extract was investigated through determination of UA levels on potassium oxonate (PO)-induced hyperuricemic rats. Extracts or standard drug treatments were orally administrated 1-h after PO administration for 14-day. Animals were euthanized and samples were collected for further experiments. The toxicity results show, no significant changes were observed in behavioral, bodyweight changes in experimental groups compared to the control. Moreover, there were no significant changes in hematological, biochemical, and histological parameters between extracts treated and control group. In the anti-hyperuricemia study, the fruit and petiole extracts treatments significantly reduced the level of UA in serum compared to the hyperuricemic model group. This study demonstrated that the extracts of A. longiloba have anti-hyperuricemic activity and was found to be non-toxic to rats in acute toxicity test.  相似文献   
79.
车红花  张明雪  何伟  侯平  顾平 《生物磁学》2012,(23):4412-4415
目的:研究益气活血中药复方对CVB3大鼠心肌细胞感染模型ATP6(ATP synthase F0 subunit 6)基因表达的作用机制。方法:本实验用新生2-3dWistar大鼠心肌细胞,建立CVB,病毒感染模型,通过改良的抑制性消减杂交技术(SSH),克隆了受CVB,攻击的心肌细胞中被中药(益气活血中药复方)调控的基因。结果:ATP6基因,在中药组中高表达,而病毒组中表达减弱或抑制。结论:益气活血中药复方能影响受CVB,病毒攻击的宿主细胞ATP6基因的表达,有效保护心肌、阻断病程进度,从而实现治疗病毒性心肌炎的目的。  相似文献   
80.
The purpose of this study is twofold: to examine macro (calcium, magnesium, and phosphorus) and trace mineral (iron) concentration in oriental supplements (OS), and to define OS prevalence in elite athletes. Participants of this study were 928 varsity athletes (male: 680, female: 248) with 23 sports types. Recent 3-month dietary supplements (DS) and OS practice was surveyed during training period, and mineral concentration in 72 randomly collected OS samples were analyzed. DS use was 41% and OS use was 20% in university elite athletes. Most common OS use informants were parents (74%). OS intake reason was for health maintenance (37%), energy supplement (25%), and recovery improvement (15%). Moreover, health maintenance was higher in females (47%) than males (32%) while energy supplement was higher in males (28%) than females (18%) (χ2(8) = 17.676, p = 0.024). Beliefs in OS efficacy and importance were significantly higher in female athletes compared to male athletes (p < 0.05). Macro mineral concentration in OS was calcium (7.54 ppm), magnesium (4.63 ppm), and phosphorus (205.34 ppb) and trace mineral concentration in OS was iron (8.10 ppb), which was a small amount. An association between OS intake reason and mineral concentration in calcium, phosphorus, and iron was found, but no association between OS intake and magnesium. In conclusion, an association between OS intake reason and mineral concentration differed by the ingredients. Minerals in OS were very small amount, which would be improved for mineral balance in elite athletes.  相似文献   
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