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571.
Myocardial infarction is one of the most common manifestations of cardiovascular disease. In the present study, we investigated
the protective effect of betaine, a potent lipotropic molecule, on changes in the levels of lysosomal enzymes and lipid peroxidation
in isoprenaline-induced myocardial infarction in Wistar rats, an animal model of myocardial infarction in man. Male albino
Wistar rats were pretreated with betaine (250 mg/kg body weight) daily for a period of 30 days. After the treatment period,
isoprenaline (11 mg/100 g body weight) was intraperitoneally administered to rats at intervals of 24 h for 2 days. The activities
of lysosomal enzymes (β-glucuronidase, β-galactosidase, β-glucosidase, and acid phosphatase) were significantly (p < 0.05) increased in plasma with a concomitant decline in the activities of these enzymes in heart tissue of isoprenaline-administered
rats. Also, the level of lipid peroxidation was higher in heart lysosomes of isoprenaline-injected rats. Pretreatment with
betaine daily for a period of 30 days to isoprenaline-induced rats prevented the changes in the activities of these lysosomal
enzymes. Oral treatment with betaine (250 mg/kg body weight) to normal control rats did not show any significant effect in
all the biochemical parameters studied. Thus, the results of our study show that betaine protects the lysosomal membrane against
isoprenaline-induced myocardial infarction. The observed effects might be due to the free radical-scavenging and membrane-stabilizing
properties of betaine. 相似文献
572.
573.
We report an in vitro selection method that has led to isolation of Fusarium wilt and Alternaria leaf spot disease-tolerant plantlets in cotton (Gossypium hirsutum L. cv. SVPR2). Embryogenic callus was isolated from hypocotyl explants of cotton cultured on 5–50% Fusarium oxysporum culture filtrate-fortified callus induction medium. Somatic embryos tolerant to fungal culture filtrate (FCF) were isolated from this embryogenic callus on somatic embryo regeneration medium fortified with 40% FCF. Sixteen plantlets were selected as FCF-tolerant from 34 somatic embryos tested, which corresponds to about 47% success rate. The FCF-tolerant plants were analyzed for disease tolerance by challenging them with spores of F. oxysporum and Alternaria macrospora. Four plants were selected as F. oxysporum tolerant from a total of 24 plants tested. The selected plants showed an enhanced survival rate compared with the control when they were grown in earthen pots inoculated with 1 × 105 spores/mL of F. oxysporum. From the FCF-tolerant plants, another nine randomly selected plantlets were challenged with spores of A. macrospora in order to test their tolerance to Alternaria leaf spot disease. The number of lesions per leaf significantly decreased from 8.2 to 0.9 and the lesion lengths were also reduced from 2.8 to 1.2 mm per leaf spot in these plants. Electrophoresis analysis of extracellular proteins from the FCF-tolerant plants showed enhanced secretion of proteins in the range of 24–36 kDa. Isozyme analysis by of FCF-tolerant plants by using native gels showed the presence of chitinase. Quantitative analysis showed that there was 13-fold increase in a chitinase activity in the selected FCF-tolerant plants compared to the control plants. Our results show that over-expression of chitinase enzyme leads to enhanced disease resistance against F. oxysporum and A. macrospora. 相似文献
574.
575.
Gaurav K. Mehta Ramavatar Meena Kamalesh Prasad M. Ganesan A. K. Siddhanta 《Journal of applied phycology》2010,22(5):623-627
Superior quality non-methylated and low-sulphated galactans were extracted from two Indian agarophytes namely Gracilaria debilis and G. salicornia growing naturally along the west coast of India, using an eco-friendly method developed in our laboratory. The galactans
were characterised by FT-IR, 13C NMR, GC-MS, ICP, GPC and rheological measurements. G. debilis produced exclusively non-methylated galactan exhibiting the greatest gel strength of 650±25 g cm−2 and lowest sulphate of 0.21±0.06%. On the contrary, G. salicornia polysaccharide was composed of non-methylated galactose (major) and mannose (minor), having gel strength of 510±25 g cm−2 and sulphate of 0.45±0.06%. Very low heavy metal contents were determined in both the galactan samples, which may thus be
potentially useful in food and biological applications. 相似文献
576.
G Ganesan D Ganesan R H Bradford 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1976,151(2):390-394
These studies demonstrate that canine liver synthesizes a TGH activated by C-I but not by C-II. This TGH has properties similar to lipoprotein lipase C-I isolated from postheparin plasma of human subjects, but differs from a previously reported liver triglyceride-lipase or protamine insensitive-lipase in its sensitivity to NaCl and protamine sulfate, as well as in its requirement for a serum cofactor, C-I. These data suggest the possiblity that, in dogs, liver is a source of plasma LPLC-I. 相似文献
577.
578.
Bioprocess and Biosystems Engineering - Bacillus pumilus, the thermophilic microorganism, was used to biosynthesise lipase of specific activity 5173 U. The purified lipase was highly stable in the... 相似文献
579.
Elizabeth A. Hunsperger Sutee Yoksan Philippe Buchy Vinh Chau Nguyen Shamala Devi Sekaran Delia A. Enria Susana Vazquez Elizabeth Cartozian Jose L. Pelegrino Harvey Artsob Maria G. Guzman Piero Olliaro Julien Zwang Martine Guillerm Susie Kliks Scott Halstead Rosanna W. Peeling Harold S. Margolis 《PLoS neglected tropical diseases》2014,8(10)
580.
The Land Dayaks and the Sea Kayaks of Sarawak were surveyed for haptoglobin, transferrin and serum albumin variants. The Hp1 gene frequency was 0.385 in 283 Land Dayaks as well as in 205 Sea Kayaks. The TfDChi gene frequency in 283 Land Dayaks was 0.030 and in 188 Sea Kayaks it was 0.040. Serum albumin Medan was found in one of the 188 Sea Kayaks. 相似文献