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Background

Potential biomarkers to aid diagnosis and therapy need to be identified for Amyotrophic Lateral Sclerosis, a progressive motor neuronal degenerative disorder. The present study was designed to identify the factor(s) which are differentially expressed in the cerebrospinal fluid (CSF) of patients with sporadic amyotrophic lateral sclerosis (SALS; ALS-CSF), and could be associated with the pathogenesis of this disease.

Results

Quantitative mass spectrometry of ALS-CSF and control-CSF (from orthopaedic surgical patients undergoing spinal anaesthesia) samples showed upregulation of 31 proteins in the ALS-CSF, amongst which a ten-fold increase in the levels of chitotriosidase-1 (CHIT-1) was seen compared to the controls. A seventeen-fold increase in the CHIT-1 levels was detected by ELISA, while a ten-fold elevated enzyme activity was also observed. Both these results confirmed the finding of LC-MS/MS. CHIT-1 was found to be expressed by the Iba-1 immunopositive microglia.

Conclusion

Elevated CHIT-1 levels in the ALS-CSF suggest a definitive role for the enzyme in the disease pathogenesis. Its synthesis and release from microglia into the CSF may be an aligned event of neurodegeneration. Thus, high levels of CHIT-1 signify enhanced microglial activity which may exacerbate the process of neurodegeneration. In view of the multifold increase observed in ALS-CSF, it can serve as a potential CSF biomarker for the diagnosis of SALS.  相似文献   
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Background

Resveratrol is a natural compound suggested to have beneficial health effects. However, people are consuming resveratrol for this reason without having the adequate scientific evidence for its effects in humans. Therefore, scientific valid recommendations concerning the human intake of resveratrol based on available published scientific data are necessary. Such recommendations were formulated after the Resveratrol 2010 conference, held in September 2010 in Helsingør, Denmark.

Methodology

Literature search in databases as PubMed and ISI Web of Science in combination with manual search was used to answer the following five questions: 1Can resveratrol be recommended in the prevention or treatment of human diseases?; 2Are there observed “side effects” caused by the intake of resveratrol in humans?; 3What is the relevant dose of resveratrol?; 4What valid data are available regarding an effect in various species of experimental animals?; 5Which relevant (overall) mechanisms of action of resveratrol have been documented?

Conclusions/Significance

The overall conclusion is that the published evidence is not sufficiently strong to justify a recommendation for the administration of resveratrol to humans, beyond the dose which can be obtained from dietary sources. On the other hand, animal data are promising in prevention of various cancer types, coronary heart diseases and diabetes which strongly indicate the need for human clinical trials. Finally, we suggest directions for future research in resveratrol regarding its mechanism of action and its safety and toxicology in human subjects.  相似文献   
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The effect of boron (B) on growth, water status and oxidative damage was investigated in the leaves and roots of 7-day-old seedlings of Brassica juncea var. Varuna. For this seedlings of Brassica were grown in solution culture with variable boron supply (0.033, 0.33, 3.3 and 33 mg B L?1) under controlled conditions in green house. Photosynthetic pigments were found to be decreased more under excess (3.3 and 33 mg B L–1) than deficient boron supply (0.033 mg B L–1) when compared to control (0.33 mg B L–1). Accumulation of hydrogen peroxide and thiobarbituric acid reactive substances content in both leaves and roots under deficient and excess boron supply suggested oxidative damage due to excessive production of reactive oxygen species. Increased activity of antioxidative enzymes: superoxide dismutase, catalase and peroxidase along with polyphenol oxidase was observed in leaves and roots under boron deficiency and excess than in control. Increased proline concentration, decreased total water content and water saturation deficit also indicated the water deficit condition in leaves and roots of boron-stressed Brassica seedlings.  相似文献   
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An experiment was conducted under glass house condition to study the effect of foliar application of boron (B) on reproductive biology and seed quality of black gram (Vigna mungo). Black gram (V. mungo L. var. DPU-88-31) was grown under controlled sand culture condition at deficient and sufficient B levels. After 32 days of sowing B deficient plants were sprayed with three concentrations of B (0.05%, 0.1% and 0.2% borax) at three different stages of reproductive development, i.e. prior to flowering, initiation of bud formation and after bud formation. Deficient B supply decreased the anther and pollen size, pollen tube growth, pollen viability as well as stigmatic receptivity which were increased by foliar B application. Foliar spray at all the three concentrations and at all stages increased the yield parameters like number of pods, pod size and number of seeds formed per plant. Foliar B application also improved the seed yield and seed quality in terms of storage seed proteins (albumin, globulin, glutenin and prolamin) and carbohydrates (sugars and starch) in black gram. The foliar application of B in appropriate doses (particularly 0.1%) after bud formation made quantitative and qualitative improvement in seed yield of black gram by supplementing additional/critical B requirements for reproductive development.  相似文献   
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