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91.
Glycogen is a cellular energy store that is crucial for whole body energy metabolism, metabolic regulation and exercise performance. To understand glycogen structure we have purified glycogen particles from rat liver and human skeletal muscle tissues and compared their biophysical properties with those found in commercial glycogen preparations. Ultrastructural analysis of commercial liver glycogens fails to reveal the classical α-rosette structure but small irregularly shaped particles. In contrast, commercial slipper limpet glycogen consists of β-particles with similar branching and chain lengths to purified rat liver glycogen together with a tendency to form small α-particles, and suggest it should be used as a source of glycogen for all future studies requiring a substitute for mammalian liver glycogen.  相似文献   
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Aging is an inevitable process that occurs in the whole body system accompanying with many functional and morphological changes. Inflammation is known as one of age-related factors, and inflammatory changes could enhance mortality risk. In this study, we compared immunoreactivities of inflammatory cytokines, such as interleukin (IL)-2 (a pro-inflammatory cytokine), its receptor (IL-2R), IL-4 (an anti-inflammatory cytokine), and its receptor (IL-4R) in the cervical and lumbar spinal cord of young adult (2–3 years old) and aged (10–12 years old) beagle dogs using immunohistochemistry and western blotting. IL-2 and IL-2R-immunoreactive nerve cells were found throughout the gray matter of the cervical and lumbar spinal cord of young adult and aged dogs. In the spinal cord neurons of the aged dog, immunoreactivity and protein levels were apparently increased compared with those in the young adult dog. Change patterns of IL-4- and IL-4R-immunoreactive cells and their protein levels were also similar to those in IL-2 and IL-2R; however, IL-4 and IL-4R immunoreactivity in the periphery of the neuronal cytoplasm in the aged dog was much stronger than that in the young adult dog. These results indicate that the increase of inflammatory cytokines and their receptors in the aged spinal cord might be related to maintaining a balance of inflammatory reaction in the spinal cord during normal aging.  相似文献   
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Strain DY59T, a Gram-positive non-motile bacterium, was isolated from soil in South Korea, and was characterized to determine its taxonomic position. Phylogenetic analysis based on the 16S rRNA gene sequence of strain DY59T revealed that the strain DY59T belonged to the family Deinococcaceae in the class Deinococci. The highest degree of sequence similarities of strain DY59T were found with Deinococcus radiopugnans KACC 11999T (99.0%), Deinococcus marmoris KACC 12218T (97.9%), Deinococcus saxicola KACC 12240T (97.0%), Deinococcus aerolatus KACC 12745T (96.2%), and Deinococcus frigens KACC 12220T (96.1%). Chemotaxonomic data revealed that the predominant fatty acids were iso-C15:0 (19.0%), C16:1 ω7c (17.7%), C15:1 ω6c (12.6%), iso-C17:0 (10.3%), and iso-C17:1 ω9c (10.3%). A complex polar lipid profile consisted of a major unknown phosphoglycolipid. The predominant respiratory quinone is MK-8. The cell wall peptidoglycan contained D-alanine, L-glutamic acid, glycine, and L-ornithine (di-amino acid). The novel strain showed resistance to gamma radiation, with a D10 value (i.e. the dose required to reduce the bacterial population by 10-fold) in excess of 5 kGy. Based on the phylogenetic, chemotaxonomic, and phenotypic data, strain DY59T (=KCTC 33033T =JCM 18581T) should be classified as a type strain of a novel species, for which the name Deinococcus swuensis sp. nov. is proposed.  相似文献   
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OBJECTIVE: To evaluate vascular endothelial growth factor (VEGF) expression in the successive steps of cervical neoplasia and to determine its correlation with angiogenesis and p53 status. STUDY DESIGN: Immunohistochemical staining with a VEGF monoclonal antibody was performed on a total of 161 cervical specimens representing 12 normal epithelium, 33 cervical intraepithelial neoplasia (CIN) 1, 30 CIN 3 and 86 squamous cell carcinomas. Microvessels were immunohistochemically labeled with an antibody to CD34. Computerized image analysis was used to evaluate microvessel density (MVD). p53 Status was determined by immunohistochemistry and direct sequencing of exons 5-8 of the p53 gene. RESULTS: VEGF expression progressively increased along the continuum from normal epithelium to squamous cell carcinoma (P < .05). MVD increased significantly with cervical neoplasia progression, from normal epithelium, through CIN, to squamous cell carcinoma (P < .001). A strong correlation was observed between VEGF expression and MVD (P < .001). p53 Protein expression was not detected in the normal epithelium or in CIN 1, while 3 (10%) of 30 CIN 3 and 28 (33%) of 86 squamous cell carcinomas were positive for p53. VEGF expression correlated statistically with p53 protein expression (P < .001). In double VEGF- and p53-stained sections, the 2 markers were generally expressed in the same tumor cells. Of the 4 p53 gene mutations, 3 exhibited strong VEGF expression, and 1 exhibited moderate VEGF expression. VEGF expression did not correlate significantly with outcome variables in patients with squamous cell carcinoma. CONCLUSION: Our results suggest that VEGF expression is involved in the promotion of angiogenesis in cervical neoplasia and that p53 is likely to be involved in the regulation of VEGF expression.  相似文献   
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Spinigerin is a linear antibacterial peptide derived from a termite insect. It consists of 25 amino acids and is devoid of cysteines. Spinigerin displays good lytic activities against Gram-positive and Gram-negative bacteria, but has no hemolytic activities against human erythrocytes. In this study, we present a three-dimensional solution structure of spinigerin in SDS micelles. According to CD data spinigerin has an alpha-helical conformation in the presence of TFE, DPC micelles, and SDS micelles. The three-dimensional structure of spinigerin as determined by NMR spectroscopy contains a stable alpha-helix from Lys4 to Thr23. Spinigerin (4-21), an 18-residue fragment from Lys4 to Leu21, contains a similar content of alpha-helical structure compared to native spinigerin and was found to retain antibacterial activity, too. Therefore, this alpha-helical structure and the strong electrostatic attraction between four Lys and three Arg residues in spinigerin and the negatively charged polar head groups of the phospholipids on the membrane surface play important roles in disrupting membrane and subsequent cell death.  相似文献   
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The safety assessment of Bifidobacterium longum SPM1205 isolated from healthy Koreans and this strain's inhibitory effects on fecal harmful enzymes of intestinal microflora were investigated. The overall safety of this strain was investigated during a feeding trial. Groups of SD rats were orally administered a test strain or commercial reference strain B. longum 1 x 10(9) CFU/kg body weight/day for four weeks. Throughout this time, their feed intake, water intake and live body weight were monitored. Fecal samples were periodically collected to test harmful enzyme activities of intestinal microflora. At the end of the four-week observation period, samples of blood, liver, spleen, kidney, and gut tissues were collected to determine for hematological parameters and histological differences. The results obtained in this experiment demonstrated that four weeks of consumption of this Bifidobacterium strain had no adverse effects on rat's general health status, blood biochemical parameters or histology. Therefore, it is likely to be safe for human use. Fecal harmful enzymes such as beta-glucosidase, beta-glucuronidase, tryptophanase and urease, were effectively inhibited during the administration of the B. longum SPM1205. These results suggested that this B. longum SPM 1205 could be used for humans as a probiotic strain.  相似文献   
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Lee EG  Kim JH  Shin YS  Shin GW  Suh MD  Kim DY  Kim YH  Kim GS  Jung TS 《Proteomics》2003,3(12):2339-2350
Expressed proteins and antigens from Neospora caninum tachyzoites were studied by two-dimensional gel electrophoresis and immunoblot analysis combined with matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Thirty-one spots corresponding to 20 different proteins were identified from N. caninum tachyzoites by peptide mass fingerprinting. Six proteins were identified from a N. caninum database (NTPase, 14-3-3 protein homologue, NcMIC1, NCDG1, NcGRA1 and NcGRA2), and 11 proteins were identified in closely related species using the T. gondii database (HSP70, HSP60, pyruvate kinase, tubulin alpha- and beta-chain, putative protein disulfide isomerase, enolase, actin, fructose-1,6-bisphosphatase, lactate dehydrogenase and glyceradehyde-3-phosphate dehydrogenase). One hundred and two antigen spots were observed using pH 4-7 IPG strips on immunoblot profiles. Among them, 17 spots corresponding to 11 antigenic proteins were identified from a N. caninum protein map. This study involved the construction of in-depth protein maps for N. caninum tachyzoites, which will be of value for studies of its pathogenesis, drug and vaccine development, and phylogenetic studies.  相似文献   
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