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41.
Wild-type or mutant human p53 gene was transfected into a human gastric carcinoma cell line MKN-1 which shares a mutant p53 allele. Transfected wild-type p53 reduced the colony forming efficiency and tumorigenicity of MKN-1 cells. However, no difference in expression of cell adhesion molecule, oncogenes and growth factors was observed among parent, wild-type p53 and mutant p53 transfectants. In motility assay, the wild-type p53 transfectants relative to the parental or mutant p53 transfectants exhibited a decreased motility, and HGF had a greater effect on the motility of the mutant p53 transfectants, but very little effect on the motility of either the parental or wild-type transfectants. In invasion assay, mutant p53 transfectants revealed the increased invasion ability into collagen gel. These results suggest that allele loss and point mutation of p53 gene may play a critical role not only in growth but also in invasion of gastric carcinoma cells.  相似文献   
42.
PURPOSE: This study was performed to evaluate the relationship between endosonographic findings of anal sphincters and anorectal function in patients after surgery for Hirschsprung's disease. In addition, whether internal sphincterotomy or sphincterectomy was accomplished was examined in each procedure by anal endosonography. METHODS: Fifteen patients, aged 11 to 20 years, were examined. Nine patients underwent modified Duhamel's operation, three underwent Rehbein's operation with anorectal myectomy, and three underwent modified Martin's operation. All 15 patients were examined by anal endosonography using a sonographic scanner (Aloka SSD 2000) with a 7.5-MHz radial rotating endoprobe, clinical bowel assessment, and manometric study. RESULTS: After the modified Duhamel operation, anal endosonography showed an interruption of the external anal sphincter (EAS) in eight of the nine patients, as a high, mixed, or low echoic lesion in the hyperechoic band correlated to the EAS. The locations of the interruption were wide in patients with mild constipation. An interruption of the internal anal sphincter (IAS) was observed in all nine patients, as a hyperechoic lesion in the hypoechoic band correlated to IAS, which indicated internal sphincterotomy. After Rehbein's operation with anorectal myectomy, an interruption of EAS was observed in all three patients as a high or low echoic lesion in the hyperechoic band. An interruption of IAS was observed in all three patients. After the modified Martin's operation, an interruption of EAS was observed in two of the three patients as a high or low echoic lesion in the hyperechoic band. An interruption of IAS was observed in all three patients. CONCLUSION: Anal endosonography showed detailed distributions of EAS and IAS in patients after surgery for Hirschsprung's disease and complete internal sphincterotomy or sphincterectomy after these operations.  相似文献   
43.
Low density lipoprotein (LDL) and lipoprotein(a) suppress catecholamine secretion in cultured adrenal medullary cells. Modification of LDL by oxidation or acetylation potentiates various atherogenic actions of LDL. In the present study, we investigated whether the modification of LDL influences catecholamine secretion in cultured bovine adrenal medullary cells. The exposure of LDL to CuSO4 caused a time-dependent oxidation of LDL. Maximal oxidation of LDL was observed after exposure to CuSO4 for 24 h. Native LDL inhibited catecholamine secretion induced by carbachol to 68.5% of control. Oxidized LDL caused further inhibition of carbachol-evoked secretion to 37.6% of control. Acetylated LDL inhibited it to 41.0% of control. There was a good correlation between the extent of LDL oxidation and the inhibition of catecholamine secretion. These results suggest that oxidation or acetylation of LDL augments its inhibitory effect on the secretion of catecholamines. Since catecholamines are a risk factor of atherosclerosis, the inhibitory effect by such modified LDL may be a mechanism inhibiting atherosclerotic progression. Received: 29 January 1999 / Accepted: 19 April 1999 / Published online: 22 June 1999  相似文献   
44.
We report a patient with right hemiparkinsonism following haemorrhage in the left substantia nigra. The hemiparkinsonism responded to treatment with trihexyphenidyl hydrochloride and deteriorated after temporary discontinuation of the drug. Single photon emission computed tomography using technetium 99md, 1-hexamethylpropyleneamine oxide showed reduced uptake in the left putamen, globus pallidus and thalamus.  相似文献   
45.
Summary The neuropathological findings in a Japanese male with nephrosialidosis are reported. Clinically, coarse face, psychomotor retardation, macular cherryred spot and proteinuria were noted at 1 year and 7 months. He was diagnosed to have nephrosialidosis on the basis of a deficiency of -neuraminidase activity in both lymphocytes and cultured skin fibroblasts, and of severe glomerular and tubular involvement on renal biopsy. He died of multiple organ failure at 8 years and 6 months. There were numerous vacuoles and storage materials in visceral organs, particularly in the glomerular and tubular epithelial cells of the kidney and Kupffer cells as well as hepatocytes in the liver. Neuropathological examination revealed severe neuronal storage in the selected part of the central nervous system; lower motor neurons of the brain stem and spinal anterior horn cells, as well as neurons in the basal nucleus of Meynert. In the peripheral nervous system, sympathetic ganglia were severely affected. There was little or no neuronal storage in the basal ganglia, cerebral cortex or cerebellum, and demyelination was not found. Electron microscopic examination showed fine wavy multilamellar structures in the spinal anterior horn cells or Zebra body-like structures in the neurons of the Meynert's basal nucleus. Lectin histochemistry was positive for wheat germ agglutinin, Ricinus communis agglutinin-1 and peanut agglutinin within distended neurons. We conclude that the neuropathological feature in nephrosialidosis is not specific except for the selectiveness of the anatomical sites of involvement. It shares some aspects found in other types of sialidosis or galactosialidosis.  相似文献   
46.
Summary Maximum motor nerve conduction velocities in the median nerve (MCV) and blood lead (PbB) were repeatedly measured in 14 lead exposed workers with an initial PbB from 0.7 to 4.0 mol/kg (median 2.3 mol/kg) for a period from 3 months to 7 years: A certain dose of Calcium Disodium Ethylenediaminetetraacetic Acid (CaEDTA) was injected intravenously into most of the subjects during the period.In seven subjects, MCV improved by more than 4 m/s during the observation period which involved the first two successive measurements of MCV and PbB, but the remaining seven subjects showed the minimal alteration (within ± 4.0 m/s). The initial value of MCV was significantly slower (P < 0.01) and the decrease in PbB was significantly greater (P < 0.05) in the group of subjects having shown the improvement of MCV by more than 4 m/s.The initial value of MCV was significant in determining the alteration in MCV in multiple regression analysis and, together with the change in PbB, explained 31% of the alteration in MCV between the first two successive measurements. The initial level of PbB, dose of CaEDTA, time interval between the measurements and age played no essential part in the alteration in MCV.The alteration in MCV throughout the whole observation period in each subject significantly correlated with the concurrent change in PbB (r=–0.573, P < 0.001).  相似文献   
47.
PURPOSE: The purpose is to assess clinical significance of matrix metalloproteinase (MMP)-2 and MMP-9 status, especially MMP-2 status, in stromal cells in non-small-cell lung cancer (NSCLC) because experimental studies have revealed that stromal MMP-2 plays important roles in progression of malignant tumors, but most clinical studies focused on tumoral MMP-2 expression, not stromal MMP-2 expression. EXPERIMENTAL DESIGN: We conducted a retrospective study on MMP-2 and MMP-9 expression as evaluated immunohistochemically in a total of 218 consecutive patients with completely resected pathological stage I-IIIA, NSCLC. RESULTS: Strong MMP-2 expression in tumor cells and stromal fibroblasts were documented in 54 (24.8%) and 132 (60.6%) patients, respectively. Strong MMP-2 expression in stromal fibroblasts was more frequently seen in squamous cell carcinoma (72.7%) than in adenocarcinoma (54.9%; P = 0.016). Tumors showing strong MMP-2 expression in stromal fibroblasts showed a significantly higher intratumoral microvessel density (IMVD) than weak stromal MMP-2 tumors (mean intratumoral microvessel density, 50.9 versus 32.4, P = 0.003). In addition, postoperative prognosis of strong stromal MMP-2 patients was significantly poorer than that of weak stromal MMP-2 patients (5-year survival rate, 77.5 versus 60.2%, P = 0.032), and the prognostic significance was enhanced in squamous cell carcinoma patients but disappeared in adenocarcinoma patients. Multivariate analyses confirmed that strong stromal MMP-2 expression was a significant factor to predict a poor prognosis in squamous cell carcinoma patients, not in adenocarcinoma patients. In contrast, MMP-2 or MMP-9 status in tumor cells was not a significant prognostic factor. CONCLUSIONS: MMP-2 status in stromal fibroblasts, not in tumor cells, was a significant prognostic factor associated with angiogenesis in NSCLC.  相似文献   
48.
OBJECTIVE: To evaluate the characteristic patterns of facial expression in fetuses aged from 28 to 34 weeks using 4-dimensional (4-D) ultrasonography. METHODS: The faces of 10 healthy fetuses aged from 28 to 34 weeks were recorded continuously for 15 min with a 4-D ultrasonographic machine performing up to 25 frames per second. The occurrence rates of blinking, mouthing, yawning, tongue expulsion, smiling, scowling, and sucking were evaluated. RESULTS: Mouthing was the most frequent facial expression (median, 6.5; range, 2-19) whereas the least frequent were scowling (median, 1; range, 0-9) and sucking (median, 1; range, 0-2). Mouthing was evident in all fetuses and significantly more frequent than any other movement (P<.05). Yawning (median, 3; range, 0-6), smiling (median, 2; range, 0-9), and blinking (median, 1.5; range, 0-6) were observed in most cases. Tongue expulsion (median, 1.5; range, 0-5), scowling, and sucking were each observed in 6 cases. CONCLUSION: 4-D sonography provides a means of evaluating fetal facial expression early in the third trimester. It may be a key to predicting fetal brain function and well-being and an important modality in future fetal neurophysiologic research.  相似文献   
49.
目的 研究细胞间信息传递机制之一假单胞菌喹诺酮信号(PQS)在铜绿假单胞菌发病机制中的作用.方法 基于基因融合分析在转录研究中的实用性,构建了两种PQS相关对照质粒和整合突变株.一种是酶切质粒pYHP441获得pqsA'-lacZ片段后,亚克隆入质粒miniCTX-1中,构建成pqsA'的阳性表达质粒,随后将构建的质粒,通过双亲交配过程整合入野生型铜绿假单胞菌株PAO-1染色体组中;另一种是通过点特异插入诱变策略,将四环素基因盒插入启动子pqsD和pqsE之间,构建的阴性质粒转化入大肠杆菌S17-1株后,和上述pqsA'阳性表达突变株进行双亲交配过程.结果 针对今后PQS的相关研究,构建得到稳定表达PQS的质粒和阳性突变株作为阳性对照.构建获得pqsA-E启动子敲除质粒和相应PQS表达受阻的整合突变株作为阴性对照.结论 两种质粒和整合突变株的构建成功,使得PQS的相关研究结论具有客观性、精确性和有效性.  相似文献   
50.
Background. To examine whether biological features of primary tumor can help preoperative evaluation of mediastinal nodal status in non-small cell lung cancer.

Methods. A total of 450 patients who underwent tumor resection and mediastinal dissection were reviewed. p53 status and proliferative fraction (PI) were evaluated immunohistochemically.

Results. The accuracy of preoperative evaluation of mediastinal nodal status with computed tomography (CT) was 72.2%; mediastinal nodal metastases had not been revealed until operation in 59 patients (13.1%) (false-negative), and no metastasis was revealed in 66 patients (14.7%) although mediastinal nodal enlargement had been demonstrated by CT (false-positive). The number of false-negative patients was significantly larger when p53 aberrant expression was positive or when PI was higher. Combined with p53 status and PI, there were 27 false-negatives (24.1%) among patients with aberrant p53 expression and higher PI, whereas only two false-negatives (1.5%) among those with negative p53 expression and lower PI.

Conclusions. Mediastinoscopy may be recommended for tumor showing aberrant p53 expression and higher PI, even when CT demonstrates no mediastinal nodal enlargement.  相似文献   

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