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81.
82.
Reactive oxygen species have been implicated in pathogenesis injury after ischaemia-reperfusion (I/R). Caffeic Acid Phenethyl Ester (CAPE), an active component of honeybee propolis extract, exhibits antioxidant and anti-inflammatory properties. The aim of this study was to investigate the effects of CAPE on erythrocyte membrane damage after hind limb I/R. Rats were divided into two groups: I/R and I/R with CAPE pre-treatment. They were anaesthetized with intramuscular ketamine 100 mg kg(-1). A 4-h I/R period was performed on the right hind limb of all animals. In the CAPE-treated group, animals received CAPE 10 microm by intraperitoneal injection 1 h before the reperfusion. At the end of the reperfusion period, a midsternotomy was performed. A 5-ml blood sample was withdrawn from the ascending aorta for biochemical assays. Serum and erythrocyte membrane MDA levels were significantly lower in the CAPE-treated group when compared to the I/R group ( p = 0.001 and p<0.001, respectively). Erythrocyte membrane Na(+)-K(+) ATPases activity in the CAPE-treated group was significantly higher than the I/R group ( p<0.001). In conclusion, CAPE seems to be effective in protecting against oxidative stress. Therefore, we suggest that in order to decrease I/R injury, pre-administration of CAPE may be a promising agent for a variety of conditions associated with I/R.  相似文献   
83.
DNA-based methods are increasingly important for bacterial typing. The high number of polymorphic sites present among closely related bacterial genomes is the basis for the presented method. The method identifies multilocus genomic polymorphisms in intergenic regions termed AILP (amplified intergenic locus polymorphism). For each locus, a pair of unique PCR primers was designed to amplify an intergenic sequence from one open reading frame (ORF) to the adjacent ORF. Presence, absence, and size variation of the amplification products were identified and used as genetic markers for rapidly differentiating among strains. Polymorphism was evaluated using 18 AILP sites among 28 strains of Listeria monocytogenes and 6 strains of Listeria spp. and 30 AILP markers among 27 strains of Escherichia coli. Up to four alleles per locus were identified among Listeria strains, and up to six were identified among E. coli strains. In both species, more than half of the AILP sites revealed intraspecies polymorphism. The AILP data were applied to phylogenetic analysis among Listeria and E. coli strains. A clear distinction between L. monocytogenes and Listeria spp. was demonstrated. In addition, the method separated L. monocytogenes into the three known lineages and discriminated the most common virulent serotypic group, 4b. In E. coli, AILP analysis separated the known groups as well as the virulent O157:H7 isolates. These findings for both Listeria and E. coli are in agreement with other phylogenetic studies using molecular markers. The AILP method was found to be rapid, simple, reproducible, and a low-cost method for initial bacterial typing that could serve as a basis for epidemiological investigation.  相似文献   
84.
CFC (cardiofaciocutaneous) syndrome (MIM 115150) has been considered by several authors to be a more severe expression of Noonan syndrome. Affected patients present with congenital heart defects, cutaneous abnormalities, Noonan-like facial features and severe psychomotor developmental delay. We have recently demonstrated that Noonan syndrome can be caused by missense mutations in PTPN11(MIM 176876), a gene that encodes the non-receptor protein tyrosine phosphatase SHP-2. In this report, we have evaluated the possible involvement of mutations in PTPN11 in CFC syndrome. A cohort of 28 CFC subjects rigorously assessed as having CFC based on OMIM diagnostic criteria was examined for mutations in the PTPN11 coding sequence by using DHPLC analysis. The results showed no abnormalities in the coding region of the PTPN11 gene in any CFC patient, nor any evidence of major deletions within the gene suggesting that mutations in other gene(s) are responsible for this syndrome.  相似文献   
85.
The temperature-dependence of both the lipid order parameter (SDPH) and acetylcholinesterase (AChE) activity from native and cholesterol-enriched human erythrocyte membranes was investigated. Cholesterol enrichment abolishes an inflection observed around 30 degrees C in the temperature-dependence of native membrane lipid order parameter, whereas the Arrhenius plot of the enzymic activity is substantially unaffected. These results support the view that the breaks in the Arrhenius plot of the enzyme activity are not related to sudden changes of bulk membrane physical state, but arise from a direct effect of temperature on enzyme conformation.  相似文献   
86.
Tibial muscular dystrophy (TMD) is a rare autosomal dominant distal myopathy with late adult onset. The phenotype is relatively mild: muscle weakness manifests in the patient's early 40s and remains confined to the tibial anterior muscles. Histopathological changes in muscle are compatible with muscular dystrophy, with the exception that rimmed vacuoles are a rather common finding. We performed a genomewide scan, with 279 highly polymorphic Cooperative Human Linkage Center microsatellite markers, on 11 affected individuals of one Finnish TMD family. The only evidence for linkage emerged from markers in a 43-cM region on chromosome 2q. In further linkage analyses, which included three other Finnish TMD families and which used a denser set of markers, a maximum two-point LOD score of 10.14 (recombination fraction of .05) was obtained with marker D2S364. Multipoint likelihood calculations, combined with the haplotype and recombination analyses, restricted the TMD locus to an approximately 1-cM critical chromosomal region without any evidence of heterogeneity. Since all the affecteds share one core haplotype, the dominance of one ancestor mutation is obvious in the Finnish TMD families. The disease locus that was found represents a novel muscular dystrophy locus, providing evidence for the involvement of one additional gene in the distal myopathy group of muscle disorders.  相似文献   
87.
Priming with interferon prior to poly(I).poly(C) treatment of a mouse cell line, MO 57/2, followed by sequential administration of metabolic inhibitors, resulted in the production of high yields of mouse interferon.  相似文献   
88.
89.
Intravenous inoculation of mice with vaccinia virus produced characteristic lesions of the tail surface which were suppressed by intraperitoneal administration of interferon and polyacrylic acid (PAA). Polymethacrylic acid (PMAA) stimulated the formation of vaccinia virus lesions. For full activity, both interferon and PAA must be given prior to infection. PAA was still significantly effective at small dose levels (3 mg/kg) and achieved protection for at least 4 weeks. Protection increased with increasing molecular weight of the polymer. The mode of action of PAA is discussed.  相似文献   
90.
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