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1.
S-Adenosyl-L -methionine (SAM) is an essential metabolite in all living organisms. In clinical research, SAM has also been suggested as a chemotherapeutic agent in various diseases. The main problem of SAM is its instability at high temperatures, at neutral and alkaline pH, and in the presence of humidity. SAM retention in spray-dried powder was determined under various conditions of spray-drying. The highest SAM retention was obtained when maltodextrin (dextrose equivalent, DE, of 25) was used as the carrier solid with the SAM feed liquid at pH 4.0. The water content in the powder had a significant effect on the stability of SAM. SAM powder with lower water content exhibited higher stability.  相似文献   
2.
Effect of high-intensity endurance training on isokinetic muscle power   总被引:1,自引:0,他引:1  
The purpose of this study was to determine the effects of high-intensity endurance training on isokinetic muscle power. Six male students majoring in physical-education participated in high intensity endurance training on a cycle ergometer at 90% of maximal oxygen uptake (VO2max) for 7 weeks. The duration of the daily exercise session was set so that the energy expenditure equalled 42 kJ.kg-1 of lean body mass. Peak knee extension power was measured at six different speeds (30 degrees, 60 degrees, 120 degrees, 180 degrees, 240 degrees, and 300 degrees.s-1) with an isokinetic dynamometer. After training, VO2max increased significantly from mean values of 51.2 ml.kg-1.min-1, SD 6.5 to 56.3 ml.kg-1.min-1, SD 5.3 (P less than 0.05). Isokinetic peak power at the lower test speeds (30 degrees, 60 degrees and 120 degrees.s-1) increased significantly (P less than 0.05). However, no significant differences in muscle peak power were found at the faster velocities of 180 degrees, 240 degrees, and 300 degrees.s-1. The percentage improvement was dependent on the initial muscle peak power of each subject and the training stimulus (intensity of cycle ergometer exercise).  相似文献   
3.
Amyloid A protein (AA), the major fibril protein in AA-amyloidosis, is an N-terminal cleavage product of the precursor protein, serum amyloid A (SAA). Using mass spectrometry and amino-acid sequencing, we identified and characterized two novel AA protein subsets co-deposited as amyloid fibrils in an patient having AA-amyloidosis associated with rheumatoid arthritis. One of the AA proteins corresponded to positions 2–76 (or 75) of SAA2α and the other corresponded to positions 2–76 (or 75) of known SAA1 subsets, except for position 52 or 57, where SAA1α has valine and alanine and SAA1β has alanine and valine in position 52 and 57, respectively, whereas the AA protein had alanine at the both positions. Our findings (1), demonstrate that not only one but two SAA subsets could be deposited together as an AA-amyloid in a single individual and (2), support the existence of a novel SAA1 allotype, i.e., SAA152,57Ala.  相似文献   
4.
The effects of ovarian hormones on glucose and fatty acid oxidation during exercise were investigated in adult female ovariectomized rats. Rats subdivided into 3 groups received intraperitoneal injections of hormones or sesame oil for 8 days. Estrogen (E) treated rats received 17-beta estradiol in daily doses of 2 micrograms. Estrogen and progesterone treated rats (EP) received 17-beta estradiol in daily doses of 2 micrograms and 2 mg, respectively. Control rats (S) received sesame oil alone. After an overnight fast, rats ran at the speed of 25 m.min-1 for 60 min. [U-14C]glucose or [1-14C]palmitate was injected into rats at 5 min of exercise and before 10 min of exercise, respectively. Expired 14CO2 was collected using bottomless chamber on a treadmill belt. No significant differences were found in mean blood glucose, lactate and plasma free fatty acid concentrations after the exercise. Until the end of the exercise 34.7 +/- 2.6 (E, n = 5), 40.8 +/- 2.9 (EP, n = 5) and 43.7 +/- 3.5% (S, n = 6) (mean +/- SE) of 14C which was injected as 14C-glucose was recovered as 14CO2. During 60 min of the exercise 27.5 +/- 1.0 (E, n = 7), 19.8 +/- 2.7 (EP, n = 6) and 25.0 +/- 1.9% (S, n = 6) of 14C which was injected as 14C-palmitate was recovered as 14CO2. A significant difference was found in this rate between E and EP (P less than 0.05). It was concluded that estrogen treatment stimulated fatty acid oxidation compared with the estrogen plus progesterone treatment and tended to inhibit glucose oxidation during prolonged exercise.  相似文献   
5.
Synthesis of D-cysteine from 3-chloro-D-alanine and hydrogen sulfide is catalyzed by highly purified 3-chloro-D-alanine hydrogen chloride-lyase from Pseudomonasputida. The synthetic reaction proceeds optimally at pH 8.5, as a function of enzyme concentration and incubation time. The enzymatically synthesized D-cysteine was isolated from the large scale reaction mixture and identified by physicochemical means.  相似文献   
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7.
1,3-Butadiene is on the list of Substances Requiring Priority Action published by the Central Environmental Council of Japan in 1996. Emission of 1,3-butadiene has been controlled by a voluntary reduction program since 1997. Although the industrial emission of 1,3-butadiene in Japan has decreased in recent years, primarily due to a voluntary industrial emissions reduction program, the risks of exposure to it remain largely unknown. We assessed the risks and consequences of exposure to 1,3-butadiene on human health. A remarkable advantage of our risk assessment approach is the detailed assessment of exposure. Previously, we developed two different models that can be applied for the assessment of exposure: the first, the AIST-ADMER model estimates regional concentration distributions, whereas the second, the METI-LIS model estimates concentration distributions in the vicinity of factories. Both models were used for the assessment of exposure to 1,3-butadiene. Using exposure concentration and carcinogenic potency determined and reported by Environment Canada and Health Canada, we evaluated the excess lifetime cancer risk for persons exposed to 1,3-butadiene over the course of a lifetime. The results suggested that the majority of the population in Japan has an excess lifetime cancer risk of less than 10(-5), whereas a small number of people living close to industrial sources had a risk of greater than 10(-5). The results of the present assessment also showed that 1,3-butadiene in the general environment originates primarily from automobile emissions, such that a countermeasure of reducing emissions from cars is expected to be effective at reducing the total cancer risk among Japanese. On the other hand, individual risks among a population living in the vicinity of certain industrial sources were found to be significantly higher than those of the population living elsewhere, such that a reduction in emissions from a small number of specific industrial sources should be realized in order to reduce the high level of individual risk. Based on the results of our assessment, the Industrial Structure Council of the Ministry of Economy, Trade and Industry (METI) in Japan decided to announce that the voluntary reduction program had been successful, and that emissions reductions should no longer be targeted across all industries in general, but instead that such reductions should be carried out in a small number of selected factories that emit excessively large amounts of emissions.  相似文献   
8.
Primary aldosteronism is most often caused by aldosterone-producing adenoma (APA) and bi-lateral adrenal hyperplasia. Most APAs are caused by somatic mutations of various ion channels and pumps, the most common being the inward-rectifying potassium channel KCNJ5. Germ line mutations of KCNJ5 cause familial hyperaldosteronism type 3 (FH3), which is associated with severe hyperaldosteronism and hypertension. We present an unusual case of FH3 in a young woman, first diagnosed with primary aldosteronism at the age of 6 years, with bilateral adrenal hyperplasia, who underwent unilateral adrenalectomy (left adrenal) to alleviate hyperaldosteronism. However, her hyperaldosteronism persisted. At the age of 26 years, tomography of the remaining adrenal revealed two different adrenal tumors, one of which grew substantially in 4 months; therefore, the adrenal gland was removed. A comprehensive histological, immunohistochemical, and molecular evaluation of various sections of the adrenal gland and in situ visualization of aldosterone, using matrix-assisted laser desorption/ionization imaging mass spectrometry, was performed. Aldosterone synthase (CYP11B2) immunoreactivity was observed in the tumors and adrenal gland. The larger tumor also harbored a somatic β-catenin activating mutation. Aldosterone visualized in situ was only found in the subcapsular regions of the adrenal and not in the tumors. Collectively, this case of FH3 presented unusual tumor development and histological/molecular findings.  相似文献   
9.
We had previously isolated a facultatively anaerobic hyperthermophilic archaeon, Pyrobaculum calidifontis strain VA1. Here, we found that strain VA1, when grown under aerobic conditions, harbors high catalase activity. The catalase was purified 91-fold from crude extracts and displayed a specific activity of 23,500 U/mg at 70 degrees C. The enzyme exhibited a K(m) value of 170 mM toward H(2)O(2) and a k(cat) value of 2.9 x 10(4) s(-1).subunit(-1) at 25 degrees C. Gel filtration chromatography indicated that the enzyme was a homotetramer with a subunit molecular mass of 33,450 Da. The purified catalase did not display the Soret band, which is an absorption band particular to heme enzymes. In contrast to typical heme catalases, the catalase was not strongly inhibited by sodium azide. Furthermore, with plasma emission spectroscopy, we found that the catalase did not contain iron but instead contained manganese. Our biochemical results indicated that the purified catalase was not a heme catalase but a manganese (nonheme) catalase, the first example in archaea. Intracellular catalase activity decreased when cells were grown anaerobically, while under aerobic conditions, an increase in activity was observed with the removal of thiosulfate from the medium, or addition of manganese. Based on the N-terminal amino acid sequence of the purified protein, we cloned and sequenced the catalase gene (kat(Pc)). The deduced amino acid sequence showed similarity with that of the manganese catalase from a thermophilic bacterium, Thermus sp. YS 8-13. Interestingly, in the complete archaeal genome sequences, no open reading frame has been assigned as a manganese catalase gene. Moreover, a homology search with the sequence of kat(Pc) revealed that no orthologue genes were present on the archaeal genomes, including those from the "aerobic" (hyper)thermophilic archaea Aeropyrum pernix, Sulfolobus solfataricus, and Sulfolobus tokodaii. Therefore, Kat(Pc) can be considered a rare example of a manganese catalase from archaea.  相似文献   
10.
A biofertilizer, showing antagonistic activity against potato common scab in pot tests, was produced from swine feces with a newly isolated strain, CH-33, identified as Streptomyces albidoflavus. This strain characteristically grew on fresh swine feces at 20~35°C without sterili-zation or any additives, and produced an antibiotic substance against Streptomyces scabies, the common scab-pathogen, during composting. The addition of the biofertilizer at from 0.1 g to 1.6 g total nitrogen (N) per 600 g humic volcanic ash soil in a pot did not inhibit the growth of Brassica rapa var. perviridis but increased it, even at the highest nitrogen content tested. Common scab was completely inhibited when the biofertilizer was added at 0.1 g to 1.6g as nitrogen (N) per 4 kg of scab-infected soil in a pot. Thus a biofertilizer suppressing plant pathogenic microorganisms was developed.  相似文献   
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