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91.
We analyzed lipoprotein profiles in 616 Japanese by biphasic agarose gel electrophoresis using Chol/Trig Combo(TM) to yield HDL, VLDL, LDL and CM fractions which were stained with cholesterol and triglyceride reagents, respectively. To further evalute the pattern of electrophoresis, we analyzed the fraction between VLDL and LDL to confirm the possibility of a MidBand by using an automatic-five-fraction function. The cholesterol concentrations in MidBand (MidBand-C) showed a good correlation to remnant-like particle-cholesterol (RLP-C) (r = 0.95) in 23 consecutive samples (TC < 220 mg/dl, Lp(a) < 30 mg/dl). However, MidBand-C concentrations of subjects with high Lp(a) levels (Lp(a) > 30 mg/dl) were also high compared to RLP-C concentrations. The average MidBand-C levels in elderly normolipidemic control subjects (TC < 220, TG < 150) were 5.2 +/- 2.4 mg/dl in 30 males (mean age, 70 +/- 10 years) and 5.4 +/- 2.0 mg/dl in 40 females (64 +/- 11 years). The average MidBand-C levels of normolipidemic patients with coronary artery diseases (CAD; TC < 220, TG < 150) were 9.4 +/- 4.1 mg/dl in 126 males (mean age, 66 +/- 10 years) and 9.1 +/- 4.0 mg/dl in 44 females (67 +/- 10 years). These levels were significantly higher than control values (p < 0.0001). Areas under ROC curves were greater for MidBand-C than for TC, LDL-C and TG when used to discriminate between the patients with CAD and normolipidemic control subjects for each sex. There results suggest that the MidBand-C level may be useful as an indicator of risk for CAD.  相似文献   
92.
Huntington's disease is a progressive neurodegenerative disorder caused by a polyglutamine repeat expansion in the first exon of the huntingtin (Htt) protein. N-terminal Htt peptides with polyglutamine tracts in the pathological range (51-122 glutamines) form high-molecular-weight protein aggregates with fibrillar morphology in vitro, and they form discrete inclusion bodies in a cell-culture model. However, in some studies, formation of discrete Htt inclusions does not correlate well with cell death. We coexpressed N-terminal Htt fragments containing 91 glutamines fused to different affinity tags in HEK293 cells, and we isolated small aggregates by double sequential-affinity chromatography to assure the isolation of multimeric molecules. Transmission electron microscopy and atomic force microscopy revealed the isolated aggregates as globules or clusters of globules 4-50 nm in diameter without any detectable fibrillar species. Because small nonfibrillar oligomers, not mature fibrils, recently have been suggested to be the principal cytotoxic species in neurodegenerative disease, these Htt globular aggregates formed in cells may represent the pathogenic form of mutant Htt.  相似文献   
93.
The role of PKN, a fatty acid- and Rho small GTPase-activated protein kinase, in cell-cycle regulation was analyzed. Microinjection of the active form of PKN into a Xenopus embryo caused cleavage arrest, whereas normal cell division proceeded in the control embryo microinjected with buffer or the inactive form of PKN. Exogenous addition of the active form of PKN delayed mitotic timing in Xenopus egg cycling extracts judging by morphology of sperm nuclei and Cdc2/cyclin B histone H1 kinase activity. The kinase-negative form of PKN did not affect the timing, suggesting that delayed mitotic timing depends on the kinase activity of PKN. The dephosphorylation of Tyr-15 of Cdc2 was also delayed in correlation with Cdc2/cyclin B histone H1 kinase activation in extracts containing active PKN. The Cdc25C activity for the dephosphorylation of Tyr-15 in Cdc2 was suppressed by pretreatment with the active form of PKN. Furthermore, PKN efficiently phosphorylated Cdc25C in vitro, indicating that PKN directly inhibits Cdc25C activity by phosphorylation. These results suggest that PKN plays a significant role in the control of mitotic timing by inhibition of Cdc25C.  相似文献   
94.
We report on two patients with T3N1 rectal cancer treated with a combination of irinotecan, 5-fluorouracil and leucovorin as neoadjuvant chemotherapy. On days 1, 8 and 15 of this 4-week cycle, leucovorin (250 mg/m2) was administered in a 2-hour intravenous infusion, followed by 5-fluorouracil (500 mg/m2) in a 10-min intravenous bolus, and then irinotecan (80 mg/m2) in a 90-min intravenous infusion. During the chemotherapy, no grade 3-4 toxicities were observed. Two weeks after the completion of 2 cycles of this regimen, both patients underwent surgery without postoperative complications. The responses were one pathological and one macroscopic complete response. Both patients with T3 tumors were down-staged to pT0 and pT2, respectively. As for the N stage, both patients were down-staged to pN0. The combination of irinotecan/5-fluorouracil/leucovorin appears to be feasible and effective, and to have a potential as an optimal neoadjuvant therapy in patients with advanced rectal cancer.  相似文献   
95.
Beh?et's disease frequently involves the venous system, usually affecting small vessels, but sometimes large vessels such as the vena cava. Antiphospholipid antibody syndrome is associated with an increased incidence of arterial and venous thrombosis. A 29-year-old male with Beh?et's disease developed bilateral leg edema secondary to thrombotic occlusion of the inferior vena cava. Laboratory tests revealed positive antiphospholipid antibodies and lupus anticoagulant. Treatment with steroid and warfarin subsequent to intravenous administration of uro-kinase resulted in improvement of symptoms. The association of antiphospholipid antibody syndrome and Beh?et's disease may have caused the total thrombotic occlusion of the vena cava in this case.  相似文献   
96.
Gastrointestinal stromal tumors (GISTs) in the small intestine are relatively rare. We present a case of GIST arising from the small intestine, which could be resected under laparoscopic assistance. A 60-year-old male visited another hospital due to massive anal bleeding. Blood examination showed severe anemia. Although anemia improved after conservative treatment, the bleeding site was not identified and he was referred to our hospital for close examination. Abdominal CT showed a well-defined mass with homogeneous internal density in the left upper abdomen. On abdominal angiography, selective enhancement of the second jejunal artery revealed a tumor stain. Due to suspected GIST in the small intestine, laparoscopic-assisted resection of the jejunum was performed. Histopathological examination demonstrated low-grade malignant GIST. The laparoscopic procedure is considered to be useful as minimally invasive surgery for diagnosis and treatment of selected cases with GISTs in the small intestine.  相似文献   
97.
Background Apoptosis is a crucial element in the behavior of mammalian cells in many different situations. We here report the establishment of a novel monoclonal antibody (anti-LHK mAb) that has apoptosis-inducing activity against colon cancer Colo205 cells. Methods The mechanism of anti-LHK mAb-induced cell death was assessed by microscopic morphology, Annexin V/Hoechst 33528 staining, and detection of DNA fragmentation. The molecular weight of LHK antigen was determined by Western blotting. Growth inhibition of Colo205 cells induced by anti-LHK mAb was determined by in vitro and in vivo studies. Results Anti-LHK reacted with a 70-kDa antigen and completely blocked the proliferation of Colo205 cells bearing LHK in vitro in a manner characteristic of apoptosis. Strikingly, anti-LHK mAb suppressed tumor growth in a murine peritoneal dissemination model. Conclusions LHK antigen, which is restricted to epithelial cells, may be a novel death receptor that plays a critical role in controlling the growth, invasion, and metastasis of human colon cancer cells.  相似文献   
98.
We report on a 23-year-old Japanese female with a 13-year history of systemic lupus erythematosus (SLE), and two episodes of deterioration followed by treatment with high dose prednisolone. Although she had been recently treated with prednisolone (12.5 mg daily), her liver function became worse in July 1998. Results of a liver biopsy revealed multi-focal hepatic cell death in a severe fatty liver, without any inflammatory cell invasion. The biopsy also showed a positive TUNEL (Tdt-catalysed DNA nick end labelling) reaction indicating apoptosis. Her liver function recovered rapidly following steroid pulse therapy. Serum soluble Fas ligand (sFasL) was found to be elevated to a concentration of 0.395 ng/ml at the time of liver damage, but was less than 0.03 ng/ml before liver damage and after prednisolone treatment. The liver damage in this case appeared to be involved with apoptosis induced by sFasL. Although hepatitis associated with SLE is rare, apoptosis directly related to elevated sFasL levels might cause this complication.  相似文献   
99.
100.
PURPOSE: The aims of this study were to evaluate potential predictors of exfoliated free cancer cells in the peritoneal cavity and to assess intraoperative peritoneal lavage cytology as a prognostic indicator in patients with colorectal cancer. METHODS: From 1985 to 1987, intraoperative peritoneal lavage cytology was performed in 140 patients with colorectal cancer. Among them, 88 patients underwent curative resection and 52 patients had noncurative surgery. Cytology was examined twice,i.e., immediately after opening the peritoneal cavity (precytology) and just before closing the abdomen (postcytology). One hundred milliliters of saline was poured into the peritoneal cavity and it was retrieved by suction after irrigation. Cytologic examination was performed after staining with Papanicolaou, Giemsa, periodic acid-Schiff, and Alcian blue stains. RESULTS: Among the 140 patients examined, the incidence of positive cytology in the prelavage was 15 percent, and that in the postlavage was 9 percent, although it was 16 percent in either lavage. Among patients with curative resection, 10 percent had positive cytology. Seven characteristics were identified as features of tumors which are prone to exfoliate cells into the peritoneal cavity: 1) macroscopic peritoneal dissemination, 2) liver metastasis, 3) more than 20 ml of ascites, 4) ulcerated tumors without definite borders, 5) invasion of the serosal surface or beyond, 6) semiannular or annular shape, and 7) moderate or marked lymphatic invasion. In patients undergoing curative surgery, among these features, circumferential involvement was the only one correlated closely with positive cytology (P<0.02). Positive cytology was associated with a worse outcome. In patients who were resected curatively, the postcytology had a stronger influence on local recurrence than the precytology; the local recurrence rate in patients with positive postcytology was higher than in those with negative postcytology, regardless of the precytology. All patients with cancer cells in the peritoneal cavity at the end of surgery had recurrence. CONCLUSIONS: Seven characteristics were identified as risk factors for exfoliation of cancer cells into the peritoneal cavity in patients with colorectal cancer. These findings may be helpful for the choice of laparoscopic surgery in this era of increasing port-site metastases after laparoscopic procedure. The results of peritoneal lavage cytology at the end of surgery were correlated with the long-term postoperative outcome of colorectal cancer. Thus, meticulous follow-up and possibly adjuvant chemotherapy may be beneficial for patients with free cancer cells in lavage fluid, even after curative surgery.  相似文献   
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