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61.
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The expressions of heparan sulfate glycosaminoglycans (HSGAGs) in breast carcinoma specimens from 60 patients were immunohistochemically investigated using monoclonal antibodies (mAbs) that recognized different epitopes of the glycan structure. Cytoplasmic expression of GlcA-GlcNH 3 + on HSGAG was detected in carcinomas at high frequency (58.3%) using mAb JM403, whereas it was almost undetectable in normal breast ducts. This cytoplasmic expression was confirmed using confocal laser scanning microscopy. The expression of JM403 antigen in invasive carcinomas significantly correlated with nuclear atypia score (p?=?0.0004), mitotic counts score (p?=?0.0018), nuclear grade (p?=?0.0061) and the incidence of metastasis to axillary lymph nodes (p?=?0.0061). Furthermore, its expression was significantly correlated with the Ki67-labeling index in 55 invasive carcinomas (p?p? 3 + was also expressed in the cytoplasm of normal crypt epithelial cells where Ki67 protein was expressed in the cell nuclei in the proliferative compartment of the human small intestines. To date, HSGAGs have generally been found to exist on cell surface membranes and in extracellular matrices as components of HS proteoglycans, and the negatively-charged sulfated domains on HSGAGs are considered to be important for their functions. However, our present findings indicate that the cytoplasmic expression of the JM403 antigen GlcA-GlcNH 3 + on positively charged, non-sulfated HSGAG may be involved in cell proliferation and associated with increased degrees of malignancy. The unordinary carbohydrate antigen of GlcA-GlcNH 3 + on HSGAGs recognized by mAb JM403 may represent a novel proliferative biomarker for highly malignant mammary carcinomas.  相似文献   
64.
The OBIS-SEAMAP project has acquired and served high-quality marine mammal, seabird, and sea turtle data to the public since its inception in 2002. As data accumulated, spatial and temporal biases resulted and a comprehensive gap analysis was needed in order to assess coverage to direct data acquisition for the OBIS-SEAMAP project and for taxa researchers should true gaps in knowledge exist. All datasets published on OBIS-SEAMAP up to February 2009 were summarized spatially and temporally. Seabirds comprised the greatest number of records, compared to the other two taxa, and most records were from shipboard surveys, compared to the other three platforms. Many of the point observations and polyline tracklines were located in northern and central Atlantic and the northeastern and central-eastern Pacific. The Southern Hemisphere generally had the lowest representation of data, with the least number of records in the southern Atlantic and western Pacific regions. Temporally, records of observations for all taxa were the lowest in fall although the number of animals sighted was lowest in the winter. Oceanographic coverage of observations varied by platform for each taxa, which showed that using two or more platforms represented habitat ranges better than using only one alone. Accessible and published datasets not already incorporated do exist within spatial and temporal gaps identified. Other related open-source data portals also contain data that fill gaps, emphasizing the importance of dedicated data exchange. Temporal and spatial gaps were mostly a result of data acquisition effort, development of regional partnerships and collaborations, and ease of field data collection. Future directions should include fostering partnerships with researchers in the Southern Hemisphere while targeting datasets containing species with limited representation. These results can facilitate prioritizing datasets needed to be represented and for planning research for true gaps in space and time.  相似文献   
65.

Objectives

Oxidized low-density lipoprotein (oxLDL) plays a key role in the formation of atherosclerotic plaques. However, its localization in human coronary arterial wall is not well understood. The present study was performed to visualize deposition sites and patterns of native oxLDL and their relation to plaque morphology in human coronary artery.

Methods

Evans blue dye (EB) elicits a violet fluorescence by excitation at 345-nm and emission at 420-nm, and a reddish-brown fluorescence by excitation at 470-nm and emission at 515-nm characteristic of oxLDL only. Therefore, native oxLDL in excised human coronary artery were investigated by color fluorescent microscopy (CFM) using EB as a biomarker.

Results

(1) By luminal surface scan with CFM, the % incidence of oxLDL in 38 normal segments, 41 white plaques and 32 yellow plaques that were classified by conventional angioscopy, was respectively 26, 44 and 94, indicating significantly (p<0.05) higher incidence in the latter than the former two groups. Distribution pattern was classified as patchy, diffuse and web-like. Web-like pattern was observed only in yellow plaques with necrotic core. (2) By transected surface scan, oxLDL deposited within superficial layer in normal segments and diffusely within both superficial and deep layers in white and yellow plaques. In yellow plaques with necrotic core, oxLDL deposited not only in the marginal zone of the necrotic core but also in the fibrous cap.

Conclusion

Taken into consideration of the well-known process of coronary plaque growth, the results suggest that oxLDL begins to deposit in human coronary artery wall before plaque formation and increasingly deposits with plaque growth, exhibiting different deposition sites and patterns depending on morphological changes.  相似文献   
66.
Mitochondrial DNA polymorphism in Japanese   总被引:16,自引:0,他引:16  
Summary Mitochondrial DNA (mtDNA) from 116 Japanese was analyzed with nine restriction enzymes that recognize a four or five base pair sequence. The sizes of the mtDNA fragments produced by digestion by each enzyme were compared after gel electrophoresis. Double digestion experiments indicated that, in the coding region from URF2 (unidentified reading frame) to tRNAAsn (bp 5274–5691), there is an insertion of about 60 base pairs (bp) compared with the published mtDNA sequence, which is common to all individuals in the present sample. A total of 95 different morphs were detected with the nine enzymes, 60 of which have not been documented previously. Based on a comparison of the cleavage maps of all individuals, 62 different combinations of restriction types were observed. By pairwise comparison of each restriction type, the average number of nucleotide substitutions per nucleotide site () was estimated to be 0.0026. Phylogenetic analysis of the present data indicates that at least two distinct lineages exist in the Japanese population.  相似文献   
67.
Growth-related changes in the mechanical properties of collagen fascicles (approximately 300 microm in diameter) were studied using patellar tendons obtained from skeletally immature 1 and 2 months old and matured 6 months old rabbits. Tensile properties were determined using a specially designed micro-tensile tester. In each age group, there were no significant differences in the properties among cross-sectional locations in the tendon. Tangent modulus and tensile strength significantly increased with age; the rates of their increases between 1 and 2 months were higher than those between 2 and 6 months. The tangent modulus and tensile strength were positively correlated with the body weight of animals. However, growth-related changes in the mechanical properties were different between collagen fascicles and bulk patellar tendons, which may be attributable to such non-collagenous components as ground substances and also to mechanical interactions between collagen fascicles.  相似文献   
68.
Recently, the sika deer, Cervus nippon Temminck, population has increased on Mt Ohdaigahara, central Japan. The dwarf bamboo, Sasa nipponica Makino et Shibata, is a primary forage plant for sika deer in this area. To demonstrate the characteristics of S. nipponica grassland, especially as summer forage for sika deer, the habitat use intensity of sika deer was estimated by fecal densities, and biomass, growth rate, removal by deer and crude protein content were examined. Sika deer utilized the S.nipponica grassland on Mt Ohdaigahara during summer when the biomass, growth rate and crude protein content of S. nipponica were high. The recent increase in the deer population seems to be partly due to S.nipponica grassland being a favorable summer habitat.  相似文献   
69.
Among ADP-ribosyltransferases reported in eucaryotes, arginine-specific transferases from turkey erythrocytes, chicken heterophils and rabbit skeletal muscle have been purified and extensively studied. They were reported to modify a number of proteinsin vitro. ADP-ribosylation of Ha-ras-p21 and transducin by the turkey erythrocyte transferase inhibits their GTPase and GTP-binding activities. Chicken heterophil enzyme modifies several substrate proteins for protein kinases and decreases the phosphate-acceptor activity. Rabbit skeletal muscle Ca2+-ATPase is inhibited by ADP-ribosylation catalyzed by the muscle transferase. Three transferases all ADP-ribosylate small molecular weight guanidino compounds such as arginine, arginine methylester and agmatine and poly-L-arginine and nuclear histones. However, the observation that muscle transferase did not ADP-ribosylate casein or actin, both of which can be modified by the heterophil transferase under the same conditions indicates that substrate specificity of these two enzymes are different. Substrate-dependent effects were observed with polyions of nucleotides such that polyanions stimulate the ADP-ribosylation of possible target protein, p33 by chicken heterophil transferase but has no effect on the modification of casein by the same enzyme.  相似文献   
70.
Summary A huge satellite (22s+) was observed in a mentally retarded and malformed girl. It consisted of constitutive heterochromatin based on the C-band technique (CBG). In neither of the parents was the variant observed. Genetic marker studies revealed that the father was, indeed, the father of the proposita (probability, 99.8%).It is emphasized that caution must be taken in the use of chromosome variants for paternity dispute cases.  相似文献   
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