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71.
Chemical properties of lipopolysaccharides from spotted fever group rickettsiae and their common antigenicity with lipopolysaccharides from Proteus species. 总被引:2,自引:2,他引:2
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The lipopolysaccharides (LPS) isolated from spotted fever group (SFG) rickettsia strains Thai tick typhus TT-118 and Katayama were characterized by chemical analyses, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, enzyme-linked immunosorbent assay (ELISA), and immunoblotting. These LPS did not contain heptose, but they contained 3-deoxy-D-manno-octulosonic acid (KDO), glucosamine, quinovosamine, phosphate, ribose, an unknown neutral sugar, and palmitic acid. Resolution of the apparent molecular masses of these LPS by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and staining with silver showed ladder-like bands. In an ELISA, convalescent-phase sera from 10 patients with Japanese spotted fever reacted with LPS from the Katayama strain, and 90% (9 of 10) of these sera also reacted with LPS isolated from Proteus vulgaris OX2. Immunoblotting revealed that the sera reacted with the high-molecular-mass bands of LPS from SFG rickettsiae, in addition to those of OX2 LPS. In an ELISA, immunoglobulin M antibodies from these sera reacted with the O-polysaccharide and lipid A portions of LPS from P. vulgaris OX2. The epitopes common to LPS of SFG rickettsiae and P. vulgaris OX2 may be in the O-polysaccharide and lipid A portions. 相似文献
72.
Tanigaki Y Nagashima Y Kitamura Y Matsuda H Mikami Y Tsukuda M 《International journal of molecular medicine》2004,14(3):389-395
We determined whether the expression of VEGF-A and -C and their receptors, Flt-1 and Flt-4, are associated with primary tumor size, regional lymph node metastasis, distant metastasis and prognosis in patients with tongue carcinoma. The expression of VEGF-A and -C, and their receptors, Flt-1 and Flt-4, in biopsy specimens taken from 73 patients with tongue carcinoma were examined by immunohistochemical staining. VEGF-A expression was associated with distant failure and VEGF-C expression correlated with locoregional recurrence and distant failure. Furthermore, VEGF-C expression was associated with lymph node recurrence in N0 cases. Multivariate analysis revealed that VEGF-C expression was an exclusively independent factor influencing lymph node metastasis. In terms of the overall 5-year survival rate, there was no significance correlation between the overall 5-year survival rate and expression of VEGF-A, Flt-1 and Flt-4 expression, whereas there was a significant difference between VEGF-C-positive and VEGF-C-negative cases (VEGF-C-positive, 51.7% vs VEGF-C-negative, 94.2%). Furthermore, there was a significant difference between positive and negative expression for both VEGF-A and VEGF-C. Multivariate analysis revealed that lymph node metastasis and VEGF-C expression were exclusive, independent factors influencing the overall survival rate. VEGF-C expression may be a predictive factor of regional lymph node recurrence and prognosis in patients with tongue carcinoma. 相似文献
73.
Tamiko Takemura Yoshinobu Eishi Shigeru Hatakeyama Yuji Takahashi 《Pathology international》1983,33(1):159-167
An unusual case of Cushing's syndrome of a 59-year-old man with bilateral multinodular adrenal hyperplasia and microadenoma of the pituitary gland is presented. Failure to suppress plasma Cortisol with large doses of dexamethasone may suggest autonomous growth of hyperplastic nodules of the adrenals, which were at first induced by prolonged stimuli of ACTH from the microadenoma of the pituitary gland. ACTH could not be detected in the microadenoma cells on paraffin sections, while Crooke's cells were strongly positive for ACTH. The interrelation between bilateral multinodular adrenal hyperplasia and pituitary microadenoma is discussed. 相似文献
74.
Owada-Makabe K Tsubota Y Yukawa K Kakimoto N Liang XM Ichinose M Maeda M 《Neuroscience letters》2005,378(1):18-21
Attempts at protein transduction into specific restricted brain areas have remained unsuccessful. We attempted targeted, direct in vivo protein transduction by microinjecting beta-galactosidase (beta-gal) with hemagglutinating virus of Japan envelope (HVJ-E) vector into the rat nucleus tractus solitarius (NTS). The medulla oblongata including the NTS was removed 6h post-injection and cryostat sections were histochemically stained to detect beta-gal enzymatic activity. beta-gal-positive cells were present in these sections as was beta-gal activity determined by colorimetric analysis. beta-gal-positive cells were not present in the rats microinjected only beta-gal protein without HVJ-E vector. Our findings suggest that direct in vivo protein transduction into specific restricted brain areas is possible. The type of targeted delivery system we present may have wide applications in the administration of therapeutic proteins to the central nervous system. 相似文献
75.
Yuji Mizukami Fujitsugu Matsubara Takuma Hashimoto Jiro Okumura Shigeru Matsukawa Kiyoo Tanishima 《Pathology international》1987,37(2):253-260
Amylase activity was measured in thyroid tissues of various thyroid diseases and was analysed electrophoretically. Normal thyroid tissues contained significant amounts of amylase (mean ± SD; 2.71 ± 1.15 lU/g of tissue), and their amylase isozyme was composed of a majority of salivary type isoamylase and other peculiar isoamylase. The statistical decrease of amylase activities in tissues of Graves' disease under hyperthyroldism, thyroid carcinoma, and most of thyroid adenomas were found (Graves' disease; 1.04 ± 0.41, carcinoma; 1.49 ± 1.10, adenoma (except five cases with high activity); 0.88 ± 0.49 IU/g tissue). Five of 18 cases of adenoma showed strikingly higher amylase activity in their tissues. Electrophoretical patterns of amylase isoenzymes in these five adenoma tissue were different from those of normal thyroid tissues. The cellular localization of amylase in the normal thyroid tissues and the adenoma tissues was also demonstrated immunohlstochemically. 相似文献
76.
Akitaka Nonomura Yuji Mizukami Toru Hasegawa Mitsuo Ohkawa Masumi Kadoya 《Pathology international》1995,45(2):160-164
A case of a rare renal tumor showing characteristic histo-logic features is presented. The patient was a 54 year old female, whose renal tumor was incidentally detected on abdominal ultrasound (US) examination. Ultrasound, computed tomography and angiography findings were consistent with a diagnosis of renal cell carcinoma of the hypovascular type. Left nephrectomy was performed. The tumor, which measured 2.6 times2.6 times 2.5 cm, was located in the left renal cortex, and had a uniformly whitish-yellow cut surface and well-defined margin. Histologically, the tumor was characterlzed by its monomorphous growth pattern and was composed of uniformly small cells arranged in a tubular or rosette-like pattern. The tumor cells had scant cytoplasm and the nuclei were small, round and regular. These histo-logic features resembled the epithelial elements of a metanephric hamartoma in the nephroblastomatosis complex in infants. However, there was no mitosis and cellular atypia was minimal, suggesting benignity. According to these his-tologic features, the diagnosis of metanephric adenoma was made. Its clinicopathologic features are discussed. 相似文献
77.
The hippocampus is important in learning and memory functions but its ability to aid in these functions declines during aging. In this study, we examined hippocampal proteins whose expressions changed in the aging process. A comparison of synaptosome proteins of hippocampus prepared from young-adult (9-week-old) rats with those from aged (30-month-old) rats by two-dimensional fluorescence difference gel electrophoresis revealed 24 spots that were expressed differently among about 1000 spots detected in both young-adult and aged rat samples. Nineteen of these 24 spots were identified by peptide mass fingerprinting. These proteins included chaperone proteins and proteins related to the cytoskeleton, neurotransmission, signal transduction and energy supply. The cytoskeleton-related proteins included actin and T-complex 1, which is thought to play a role in actin folding. Actin was up-regulated but T-complex 1 was down-regulated in aged rat synapses. These results suggest that age-dependent changes of actin filament formation are related to neuronal dysfunction associated with aging. 相似文献
78.
Inoue H Hiraki Y Nawa T Ishizeki K 《Anatomical science international / Japanese Association of Anatomists》2002,77(4):237-246
In order to analyze the phenotypic conversion of chondrocytes, mandibular condyles of mice and rabbits were cultured under
cell and organ culture systems, and then examined by a combination of morphological and biochemical procedures. In organ culture,
mandibular condylar cartilage (MCC) obtained from newborn mice began to mineralize from the central zone and then progressively
widened towards the peripheral zone. Electron microscopic observations showed that with the increasing duration of the organ
culture, chondrocytes at the central zone converted into spindle-shaped osteoblastic cells accompanying the formation of the
bone type of thick-banded collagen fibrils. To obtain a better understanding of the chondrocytic conversion, immunolocalizations
for type I and type X collagens and osteocalcin (OC) were examined in mouse MCC cells in cell culture. Type X collagen and
OC were expressed almost simultaneously at the late stage of culture, and type I collagen was detected along the calcified
nodues after the production of these proteins. Northern blot analysis in cell cultures of rabbit MCC indicated that type II
collagen and alkaline phosphatase (ALPase) messenger ribonucleic acids (mRNAs) were highly expressed at day 7, but subsequently
decreased. In contrast, mRNA for type I collagen was expressed at a low level on day 7 and peaked on day 12. The present results
suggest that, morphologically and biochemically, cellular modification in MCC cells under culture conditions occurs at a cellular
morphological level and also at marker-gene-expression level. 相似文献
79.
Ito Y Tanaka N Fujimoto Y Yasunaga Y Ishida O Agung M Ochi M 《Journal of biomedical materials research. Part A》2004,69(3):454-461
The clinical use of cultured marrow stromal stem cells (MSCs) has recently attracted attention in the field of tissue engineering. For the clinical use of the MSCs, a prominent scaffold is needed. A scaffold hybridized with MSCs is transformed into a "bioactive bone substitute," and this provides good osteoconduction. In this study, a novel calcium hydroxyapatite ceramic with an interconnected porous structure (IP-CHA) was used as a scaffold. MSCs were harvested from Green rats containing Green Fluorescent Protein (GFP), and then these hybrids were implanted into the tibias of Sprague-Dawley rats. The purposes of this study were to examine the osteogenic ability of these hybrids without coculture, and to evaluate whether the resulting bone formation originated from the grafted MSCs or the recipient's cells. The hybridized group showed excellent bone formation compared with the IP-CHA-only implant group. Observation of the implanted MSCs revealed that they survived 8 weeks after surgery, and differentiated into osteoblast-like cells, thus providing bone formation. This implantation of the MSCs/IP-CHA composite provides excellent osteoconduction, and is expected to have extensive clinical applications. 相似文献
80.
Matsumoto S Sasaki T Imamura A Matsuo K Kayashima T Hashida A Ono S Tsujita T Matsumoto S Nakane Y Tokunaga K Okazaki Y 《American journal of medical genetics》2002,114(1):42-45
Several Caucasian studies and one Japanese study have observed associations between human leukocyte antigen (HLA) class I specificities, including A24 (9) and A26 (10) and schizophrenia. Most of those studies were conducted in 1970s and early 1980s, when the typing technique of HLA was not adequately reliable. Also, an operational diagnostic system was not employed in many of the studies. The present study investigated frequencies of HLA-A specificities in schizophrenia patients (ICD-10 and DSM-III-R, n=98) and sex-matched healthy controls (n=392) from population in the southwestern part of Japan. HLA-B and -C specificities were studied in addition. Frequencies of subjects possessing A24 and A26 were not different between the patients and controls (54% and 24% in the patients and 62% and 24% in the controls, respectively). No significant difference was found in frequencies of other class I (A, B, and C) specificities between the patients and the controls. Thus, the present study provided no evidence for an association between the HLA class I specificities, including A24, A26, and others, and schizophrenia in the Japanese population. 相似文献