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41.
BACKGROUND AND OBJECTIVES: Chromosomal instability is a common feature of pancreatic carcinoma, but its biological significance remains unclear. In this study, we investigated the association between chromosomal instability and biological aggressiveness in human pancreatic cancer cells. METHODS: Fluorescence in situ hybridization was performed to examine changes in chromosomal numbers in a total of 13 pancreatic cancer cell lines. We also assessed the potential for tumor aggressiveness within cancer cells by in vitro migration and invasion assay and by subcutaneous implantation into nude mice. RESULTS: Chromosomal instability, characterized by numerical variations in copy numbers of chromosome 8, was observed in most cell lines, and the magnitude of instability was correlated well with both motility (P < 0.001) and invasion rate (P < 0.001) of these cells. Furthermore, a significant positive correlation existed between chromosome instability and tumor growth in vivo (P < 0.01). CONCLUSIONS: These results suggest that the increased level of chromosomal instability may play a critical role in the development of aggressive tumor phenotype during pancreatic cancer progression. J. Surg. Oncol. 2001;76:181-187.  相似文献   
42.
BACKGROUND: Duodenal carcinoma is very rare and its culture cell lines have rarely been established. METHODS: Tumor cells separated from a surgically resected primary tumor of duodenal carcinoma were put into culture. The patient was an 81-year-old female and had metastatic lymph nodes. We investigated the biological characteristics of the culture cells including in vitro cell kinetics, karyotype, expression of tumor markers and integrins and tumorigenicity and histology in nude mice. RESULTS: A new cell line, designated WDC-1, was established. This duodenal carcinoma cell line proliferated in a monolayered sheet with a doubling time of 50 h. The histological findings of the xenograft in nude mice were similar to those of the primary tumor. WDC-1 cells produced carcinoembryonic antigen and expressed 1 integrin and very late antigen (VLA)-4d in vitro. CONCLUSIONS: A duodenal carcinoma cell line was established, which is rare and may contribute to progress in understanding the biological features of duodenal cancer.  相似文献   
43.
As the safety of folinic acid administration and its efficacy for reducing the toxicity of MTX remain controversial, we assessed the effect of folinic acid administration after MTX treatment for GVHD prophylaxis on the incidence of oral mucositis and acute GVHD. We retrospectively analyzed data for 118 patients who had undergone allogeneic hematopoietic SCT and had received MTX for GVHD prophylaxis. Multivariate analysis showed that systemic folinic acid administration significantly reduced the incidence of severe oral mucositis (odds ratio (OR)=0.13, 95% confidence interval (CI) 0.04-0.73, P=0.014). There was also a tendency for a lower incidence of severe oral mucositis in patients who received folinic acid mouthwash (OR=0.39, 95%CI 0.15-1.00, P=0.051). No significant difference was observed in the incidence of acute GVHD between patients who received systemic folinic acid administration and those who did not (P=0.88). Systemic folinic acid administration and mouthwash appear to be useful for reducing the incidence of severe oral mucositis in patients who have received allogeneic hematopoietic SCT using MTX as GVHD prophylaxis.  相似文献   
44.
The peptide map patterns of the nail low sulfur (LS) S-carboxymethyl keratins were investigated using Staphylococcus aureus V8 protease (V8 protease) and subtilisin. The nail LS-keratins which were analyzed by two dimensional (2D) polyacrylamide gel electrophoresis (PAGE) comprised eight major polypeptides. Since these nail LS-keratins were well separated from each other by 2D-PAGE, we could compare peptide fragments of each LS-keratin by a 2D peptide mapping. Among the eight major LS-keratins of the nail, the LS-keratins of similar size and pI values yielded many same sized peptide fragments with either proteinase. From these results, we could divide the nail LS-keratins into three groups by their molecular weights, pI values and the PAGE patterns of their peptide fragments by the proteinase digestion. Examinations of smaller sized peptide fragments produced by partial enzymatic hydrolysis with either proteinase showed strong similarities for all the nail LS-keratins. Several dense bands of same sized peptide fragments were also observed by 2D peptide mappings. On the other hand, considerable differences were observed when we compared the larger sized peptide fragments of the different group of the nail LS-keratins. These observations suggested that related structural units (domain structures) were present for all the nail LS-keratins, although they could be divided into three different groups. The LS-keratins of the epidermal cornified layer analyzed by 2D-PAGE were also composed of heterogeneous protein groups. However, when they were partially hydrolyzed by V8 protease, there appeared many same sized peptide fragments for all the epidermal LS-keratins and three dense bands of same sized peptide fragments were observed. Consequently, the 2D peptide map pattern of the epidermal LS-keratins by V8 protease was very simple as compared to that of the nail LS-keratins. Thus the molecular species composing the nail keratin filaments were more heterogeneous than those of the epidermis with respect to the distribution of glutamic acid residues in the molecules. The distribution of glutamic acid in the keratin molecules might contribute the morphological and physicochemical differences between the nail and the epidermis.  相似文献   
45.
To examine whether adolescents and adults might develop different anesthetic distribution and hemodynamic consequences after spinal injection of 0.5% tetracaine in 7.5% or 0.75% glucose, we studied 100 ASA I or II patients who were scheduled for elective surgery to the lower limb and fulfilled the following criteria: age between 13 and 16 yr (Adolescent group, n = 40) or between 25 and 74 yr (Adult group, n = 60); height between 155 and 180 cm; and body mass index between 18 and 32 kg/m(2). Patients in each group were then randomly divided into two equal subgroups to receive spinal anesthesia with 0.5% tetracaine in either 7.5% or 0.75% glucose with 0.125% phenylephrine at the L3-4 interspace. With patients in the supine horizontal position, neural block was assessed by cold, pinprick, and touch sensation and a modified Bromage scale after the injection of the study drug. The 7.5% glucose solution produced a significantly higher and faster spread of blockade in adolescents than in adults. In contrast, there were no differences in the levels of three sensory modalities between the two age groups after the 0.75% glucose solution, which produced a lower spread of blockade than the 7.5% glucose solution in either age group. Adolescents given the 0.75% glucose solution developed a smaller maximum decrease in systolic pressure than those given the heavier solution. We conclude that adolescents may develop an extensive level of blockade more easily and quickly than adults after intrathecal hyperbaric tetracaine, but that the difference may be reduced by using a less heavy solution. Implications: The influence of age on the characteristics of spinal anesthesia is still controversial. Our results show that adolescents develop blockade more extensively and quickly than adults after spinal anesthesia with 0.5%tetracaine in 7.5% glucose but not after the 0.75% glucose solution.  相似文献   
46.
Influences of the new compound MY-5116: isoamyl 5,6-dihydro-7,8-dimethyl-4,5-dioxo-4H-pyrano (3,2-C) quinoline-2-carboxylate and its metabolites were investigated on 48-hr rat homologous PCA (PCA) and the release of histamine from rat peritoneal mast cells induced by antigen antibody reaction (histamine release). MY-5116 (30 mg/kg) inhibited PCA significantly from 10 min to 2 hr after oral administration, and its ID50 (30 min) was 19.1 mg/kg. The inhibitory effect of its main metabolite, MY-1250, was the most potent among all the metabolites, 7HPQ, 8HPQ, 7CPQ and 8CPQ on the PCA (i.v.). Effect of MY-5116 suspended in 1% CMC on the PCA increased gradually after intravenous administration, but MY-1250 suppressed PCA immediately after intravenous injection. MY-5116 dissolved in DMSO in the concentration of 10(-7)-10(-6) g/ml didn't inhibit the histamine release, but the metabolite MY-1250 inhibited the histamine release. On the other experiment, MY-1250 inhibited the histamine release (IC50: 1.4 X 10(-7) g/ml), and MY-1250 was 17 times more potent than DSCG (2.4 X 10(-6) g/ml). From these results, it is suggested that MY-1250 is the main active metabolite of MY-5116.  相似文献   
47.
Case report Focal cortical dysplasia (FCD) with calcification is rare. We presented a 13-year-old epileptic patient with FCD and calcification in the left frontal lobe. At age 24, the FCD lesion and the surrounding epileptogenic cortex and underlying subcortex were removed after chronic subdural electrode recording. Histological examination showed that the calcified lesion was not independent of the FCD lesion but located in the subcortical area of the FCD lesion. A neoplastic nature was ruled out for the lesion. Discussion The pathophysiological mechanism involved in the coexistence of FCD and calcification is discussed.  相似文献   
48.
As muscle tissue constitutes a main target organ for glucose metabolism and is responsible for the development of insulin resistance, it seems plausible to elucidate the relationship between blood pressure and muscle morphology and metabolism. The association between blood pressure and capillarization/morphology of the vastus lateralis muscle and metabolic variables was evaluated in 24 perimenopausal obese women [body mass index (BMI) 34·9 ± 1·1; waist–hip ratio (WHR) 0·90 ± 0·02]. The muscle enzyme activity of lipoprotein lipase (LPL), citrate synthase and glycogen synthase was determined. There was a significant negative correlation between the percentage of type I fibres and relative fibre area of type I on the one hand and systolic and diastolic blood pressure on the other. There was a negative correlation between the capillary density (i.e. number of capillaries/muscle fibre) and a positive correlation between the diffusion distance (fibre area supplied by one capillary) and diastolic blood pressure. The activities of LPL and citrate synthase were positively correlated with the percentage of type I and negatively correlated with the percentage of type II muscle fibres. The activity of LPL was also negatively correlated with plasma glucose and the insulin/C-peptide ratio. The insulin/C-peptide ratio was positively correlated with the percentage of type II muscle fibres. In stepwise multiple regression analyses, 20–30% of the variation in systolic and diastolic blood pressure could be explained by the variables of muscle fibre distribution. Excluding muscle morphological variables from the regression model, the insulin/C-peptide ratio accounted for 13% of the variation in systolic and diastolic blood pressure. The results of the study show the close association between muscle morphology and blood pressure. It remains to be elucidated whether this association indicates a causal relationship.  相似文献   
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