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31.
To investigate genes involved in mctastatic stages of cancer, we analyzed expression of mRN As in three cell lines derived from murine colon adenocarcinoma 26 by means of a differential display method. Each of these lines exhibits distinct metastatic characteristics. Among many bands representing different expression patterns in the display, we confirmed by northern analysis that a gene corresponding to one amplified fragment, termed grm2 (gene related to metastasis 2), was expressed more abundantly in NL4, the derivative with the lowest metastatic potential, than in cell lines NL17, an experimentally metastatic derivative, and in NL22, a spontaneously metastatic derivative. Using thegrm.2 fragment as a probe, we isolated murine cDNA clones and subsequently human cDNA clones corresponding to the GRM2 gene. The human and mouse homologues both encode proteins of 600 amino-acid residues, which show weak homologies to proteins belonging to the myosin family. When we examined the expression levels of this novel gene in human colon cancers and in corresponding metastatic foci, we found that in more than half of these tissues, expression was significantly reduced in association with malignant potential. Our resultsimply that in humans the GRM2 gene product may regulate the metastatic phenotype of some colorectal cancers.  相似文献   
32.
Although percutaneous transluminal balloon aortic valvuloplasty (PTAV) has been performed for congenital aortic stenosis in infants and children for several years, its efficacy and the associated aortic regurgitation (AR) have not been widely discussed. Percutaneous transluminal balloon aortic valvuloplasty using an Inoue balloon catheter was performed for congenital aortic stenosis in 12 patients (4–16 years old) in this study. The systolic aortic valve pressure gradient ranged from 42 to 111 mmHg before PTAV and became < 50 mmHg immediately after PTAV in 10 cases (83%). Eight of these 10 patients had no increase in the gradient during subsequent observation for a period of 9–40 months. Aortic regurgitation increased immediately after PTAV in nine cases (75%). It increased from grade 1 to grade 2 in eight cases and from grade 1 to grade 3 in one patient; no significant enlargement of the left ventricular end-diastolic diameter and no significant change in the left ventricular end-diastolic pressure (LVEDP) or the cardiac index was observed during follow-up in these patients. There was a correlation between the diameter of the balloon and efficacy; an appropriate diameter was considered to be about 90% of the aortic annular diameter. Changes in the hemodynamic parameter after PTAV with an Inoue balloon were small in most patients and this procedure is considered to be a treatment that should be attempted prior to surgery for congenital aortic stenosis.  相似文献   
33.
BACKGROUND: KAI1/CD82, a tumor metastasis suppressor gene, is correlated inversely with the progression and invasion of several tumors. It also has been reported that the KAI1 gene is related to the tumor suppressor gene p53. This study was performed to clarify the correlation between KAI1/CD82 expression and clinicopathologic characteristics and p53 expression in patients with esophageal squamous cell carcinoma (ESCC). The authors also investigated mutation of the KAI1 gene coding region to determine whether this may reduce KAI1 expression in ESCC. METHODS: Using immunohistochemistry with anti-KAI1 polyclonal antibody and monoclonal antibody against p53, KAI1/CD82 and p53 expression were detected in 55 patients with ESCC who had undergone surgery. The authors examined the KAI1 gene mutation in 22 patients with ESCC by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and DNA sequencing. RESULTS: KAI1/CD82 expression was positive in 36 of 55 patients (65.5%). There was a significant inverse correlation between KAI1/CD82 expression and regional lymph node metastasis (P = 0.0045), distant metastasis (P = 0.0092), the number of lymph node metastases (P = 0.0019), and pathologic stage (P = 0.0046). The survival rates of KAI1/CD82 negative patients were poorer than those of positive patients (P = 0. 024). The correlation between KAI1 positive and p53 positive tumors was not statistically significant. None of the 22 patients with ESCC showed mutation of the KAI1 gene by PCR-SSCP. In one patient, there was polymorphism in the SSCP assay and DNA sequencing. CONCLUSIONS: The authors demonstrated immunohistochemically that the expression of KAI1 protein appeared to be correlated with lymph node metastasis. Mutation does not seem to be a mechanism for dysregulation of the KAI1 protein in ESCC.  相似文献   
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35.
OBJECTIVE: To investigate the relationship between unexplained infertility and fertilization failure from nucleoprotein defects in ejaculated human sperm and to study the usefulness of sperm chromatin assays, using AO fluorescence dye, to evaluate patients with unexplained infertility before treatment. STUDY DESIGN: From January 1999 to January 2000, 513 infertile couples had the clinical causes of their infertility assessed. During the next investigative period (February 2000-February 2001), 137 cases of unexplained infertility (n = 80) were chosen for this study, as were cases of tubal factor infertility (n = 57) as controls. The status of nuclear chromatin in ejaculated sperm was examined using acridine orange staining, followed by a conventional in vitro fertilization procedure. RESULTS: The number of patients with immature ejaculated sperm was 16 of 30 (53.3%) unexplained infertility cases involving fertilization failure, 8 of 50 (16.0%) unexplained infertility cases without fertilization failure and 5 of 57 (8.8%) tubal factor infertility cases. A significant difference was observed between unexplained infertility cases with fertilization failure and the other groups (P < .0001). CONCLUSION: These results suggest that the nuclear immaturity of ejaculated human sperm may be 1 of the primary factors underlying unexplained infertility.  相似文献   
36.
Flavonoids are widely recognized as naturally occurring antioxidants. Naringin (NG) is one of the flavonoid components in citrus fruits such as grapefruit. Hydrogen peroxide (H2O2) causes cytotoxicity through oxidative stress and apoptosis. In this paper, we examined the effects of NG on H2O2-induced cytotoxicity and apoptosis in mouse leukemia P388 cells. Cytotoxicity was determined by mitochondrial activity (MTT assay). Apoptosis and DNA damage were analyzed by measuring chromatin condensation and Comet assay (alkaline single cell gel electrophoresis), respectively. H2O2-induced cytotoxicity was significantly attenuated by NG or the reduced form of glutathione (GSH), a typical intracellular antioxidant. NG suppressed chromatin condensation and DNA damage induced by H2O2. These results indicate that NG from natural products is a useful drug having antioxidant and anti-apoptopic properties.  相似文献   
37.
This study examined trends of sickness absence before and after a psychosocial-approached health promotion program (HPP) at a Japanese worksite. The subjects were 1029 male employees working at a manufacturing company from April 1991 to March 1999. The HPP was performed from April 1995 to decrease sickness absence through helping to improve all employees' lifestyles according to a psychosocial approach incorporating six characteristics: 1) concept based on the population strategy, 2) use of a health risk appraisal (HRA), 3) setting easy lifestyle targets, 4) praising the employees' personal lifestyle initiatives, 5) supported (sponsored) by the management, 6) award of subsidiary payments. Sickness absence was considered to be consecutive days calculated by medical certification and company records. Absences due to musculoskeletal diseases and total diseases decreased, when comparing four-year periods before and after the program's introduction. In this report we show that trends of sickness absence changed after the introduction of the psychosocial-approached health promotion program.  相似文献   
38.
HYPOTHESIS: Our previous demonstrations of the feasibility of a pylorus-preserving gastrectomy with a wider-scope lymphadenectomy for early gastric cancer (GC) have raised the possibility of applying pylorus-preserving gastrectomy to a broader segment of GC patients, such as those having GC with invasion extending into the proper muscle layer (GCpm). DESIGN: Case series. SETTING: Tertiary care center. PATIENTS: This study comprised 107 patients with solitary primary GCpm located in the middle or lower third of the stomach. INTERVENTION: All patients underwent gastrectomy, using at least the former D2 dissection of the American Joint Committee on Cancer. MAIN OUTCOME MEASURES: Patterns and sites of nodal involvement were analyzed in relationship to other clinicopathologic characteristics, including preoperative and intraoperative evaluations of tumor depth (cT), nodal involvement (cN), and serosal involvement. The conditions required were serosal negativity and measurements less than or equal to cT2 cN0 with histologic proof of node negativity, or if positive, the positive nodes had to be confined to the first or selective second tier. The selective second-tier nodes were defined as those along the left gastric, common hepatic, and celiac arteries. RESULTS: The factors favoring node negativity were serosal negativity, cN0, or both. For tumors that were serosal-negative and less than or equal to cT2 cN0 to meet the above conditions, a tumor in the middle third of the stomach had to be less than or equal to 2 cm in the maximum diameter, and that in the lower third could be any size. No patients with serosal negativity and cT2 cN0 GCpm less than or equal to 2 cm in diameter died of cancer or had positive nodes beyond the selective second tier. CONCLUSIONS: Considering the required distance between the pyloric ring and distal margin of the tumor to avoid a positive resection margin, pylorus-preserving gastrectomy with a selective second-tier node dissection is optimal for tumors that are serosal negative, less than or equal to cT2 cN0, and less than or equal to 2 cm in maximum diameter when located in the middle or lower third of the stomach.  相似文献   
39.
An applicator enabling simultaneous intraluminal radiotherapy and intraluminal hyperthermia delivery was developed to improve the treatment results for locally advanced oesophageal carcinoma. Eight inoperable cases were treated by this method. Six cases received 40 Gy external irradiation followed by simultaneous intraluminal hyperthermia and radiotherapy (3 Gy and 4 Gy in three cases each) once weekly for 3 weeks; the remaining two cases received 50 Gy external irradiation followed by simultaneous intraluminal hyperthermia and radiotherapy (4 Gy) once weekly for 2 weeks. Hyperthermia was delivered by a radiofrequency current thermotherapy instrument for 30 min at an output that raised the oesophageal mucosal surface temperature to 42-43 degrees C. Intraluminal radiotherapy was delivered with a microSelectron to a submucosal depth of 5 mm after the first 15 min of hyperthermia. Four cases achieved complete response, with all demonstrating local control. Partial response was obtained in four cases, and three of these patients died of local recurrence. There were no significant adverse side effects apart from fistula in one case. In conclusion, simultaneous intraluminal radiotherapy and hyperthermia may improve the current treatment results for locally advanced oesophageal carcinoma.  相似文献   
40.
Three kinds of antibacterial substances were extracted by chloroform, ethylacetate or water from dried Shiitake mushrooms (Lentinus edodes). These substances possess efficient antibacterial activities against Streptococcus spp., Actinomyces spp., Lactobacillus spp., Prevotella spp., and Porphyromonas spp. of oral origin. In contrast, other general bacteria, such as Enterococcus spp., Staphylococcus spp., Escherichia spp., Bacillus spp., and Candida spp. were relatively resistant to these substances. Chloroform extracts had bactericidal activity against both growing and resting bacterial cells of S. mutans and P. intermedia, whereas the other two extracts showed bacteriostatic activity against both growing and resting bacterial cells of S. mutans and resting bacterial cell of P. intermedia. The antibacterial activity of chloroform extracts and ethylacetate extracts were relatively heat-stable. The water extract was heat-labile.  相似文献   
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