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41.
The modifying potential of capsaicin (CAP) on lesion development was examined in a rat multiorgan carcinogenesis model. Groups 1 and 2 were treated sequentially with diethylnitrosamine (DEN) (100 mg/kg, ip, single dose at commencement), N-methylnitrosourea (MNU) (20 mg/kg, ip, 4 doses at days 2, 5, 8, and 11), and N,N-dibutylnitrosamine (DBN) (0.05% in drinking water during weeks 3 and 4). Group 3 received vehicles without carcinogens during the initiation period. Group 4 served as the untreated control. After this initiating procedure, Groups 2 and 3 were administered a diet containing 0.01% CAP. All surviving animals were killed 20 weeks after the beginning of the experiment and the target organs examined histopathologically. The induction of GST-P+ hepatic foci in rats treated with carcinogens was significantly inhibited by treatment with CAP. CAP treatment significantly decreased the incidence of adenoma of the lung but increased the incidence of papillary or nodular (PN) hyperplasia of the urinary bladder. The tumor incidence of other organs, such as the kidney and thyroid, was not significantly different from the corresponding controls. These results demonstrated that concurrent treatment with CAP not only can inhibit carcinogenesis but can also enhance it depending on the organ. Thus, this wide-spectrum initiation model could be used to confirm organ-specific modification potential and, in addition, demonstrate different modifying effects of CAP on liver, lung, and bladder carcinogenesis.  相似文献   
42.
The spleen may be preserved during distal pancreatectomy (DP) for benign disease. The aim of this study was to compare the perioperative and postoperative courses of patients with conventional DP and spleen-preserving distal pancreatectomy (SPDP) for benign lesions or tumors with low-grade malignant potential occurred at the body or tail of the pancreas. A retrospective analysis was performed for the hospital records of all the patients undergoing DP and SPDP between January 1995 and April 2006. One-hundred forty-three patients underwent DP and 37 patients underwent SPDP. There were no significant differences in age, sex, indications of operation, estimated blood loss, operative time, and postoperative hospital stay between the two groups. Pancreatic fistula occurred in 21 (13.3%) patients following DP and in 3 (8.1%) following SPDP without a significant difference (p=0.081). Portal vein thrombosis occurred in 4 patients after DP. Splenic infarction occurred in one patient after SPDP. Overwhelming postosplenectomy infection was observed in one patient after DP. SPDP can be achieved with no increase in complication rate, operative time, or length of postoperative hospitalization as compared to conventional DP. Additionally, it has the advantage of reducing the risk of overwhelming postsplenectomy infection and postoperative venous thrombosis.  相似文献   
43.
Vascular endothelial growth factor (VEGF) is known to play a key role in tumor angiogenesis. The tumor-suppressor gene p53 has been thought to regulate VEGF. We investigated the effect of VEGF on esophageal carcinoma and the correlation between VEGF and p53. Tissue samples were taken from 81 patients with esophageal carcinoma after surgery. VEGF and p53 expressions were examined by immunohistochemical staining. Microvessels in the tumor stained for CD34 antigen were also counted. VEGF and p53 expressions were observed in 51.3% (41/80) and 51.9% (41/79), respectively. The microvessel density was 70.9+/-6.7 (mean+/-SE) in VEGF-positive group and 68.7+/-5.1 in VEGF-negative group. However, no correlation was noted between VEGF and p53 expression. Whereas the tumor size, nodal status, depth of invasions, and tumor stage were associated with poor overall survival, VEGF expression or p53 expression was not. These results indicate that VEGF and p53 are highly expressed in esophageal carcinomas. Since the VEGF expression is not correlated with the p53 expression, microvessel density or clinicopathological findings, further studies with other angiogenic molecules are needed to determine the role in esophageal carcinomas.  相似文献   
44.
Human polyomavirus (PV) interstitial nephritis has recently been recognized as a cause of severe renal allograft dysfunction. It occurs in immunosuppressed patients after reactivation of the latent virus PV type BK (BK virus) in the renal epithelium. BK disease is defined as a morphologically manifest renal infection with cytopathic signs accompanied by varying degrees of interstitial inflammatory cell infiltrates and functional impairment. It is also identified by the presence of cells containing viral inclusion bodies (decoy cells) in the urine. The authors report a case of BK PV interstitial nephritis in a 36-year-old renal allograft recipient. Under light microscopy the chief diagnostic indicator was detection of intranuclear viral inclusions, which were found exclusively in tubular epithelial cells. Cells with viral changes were often enlarged with nuclear atypia and chromatin basophilia. Widespread interstitial plasma cell infiltrates associated with tubulitis were present. Intranuclear paracrystalline arrays of virus particles 35-38 nm in diameter were present as characteristic ultrastructural indicators. Urine samples revealed decoy cells with ground-glass-type intranuclear inclusions positive for BK virus by electron microcopy.  相似文献   
45.
FVB and BALB/c mice show different morbidity, development of Clonorchis sinensis, and pathological changes following C. sinensis infection. FVB mice are susceptible and BALB/c mice are relatively more resistant to C. sinensis infection. To investigate the relationship between cytokine reaction and susceptibility to C. sinensis infection in FVB and BALB/c mice, we described both the patterns and kinetics of Th1 cytokines and Th2 cytokines in spleen cell culture. Interleukin (IL)-4 and IL-10 cytokine production in the culture supernatants of the concanavalin-A-stimulated spleen cells increased at 2–3 weeks post-infection in both strains. IL-5 production increased between 2 and 5 weeks post-infection in both strains, and reached a peak level at 2 weeks post-infection in BALB/c mice and 4 weeks post-infection in FVB mice. In contrast, gamma interferon (IFN-) production decreased between 2 and 4 weeks in both strains. IL-2 production increased slightly in BALB/c mice following infection, but was unchanged in FVB mice. IL-4 production over preinfection levels was significantly higher in FVB mice, whereas IFN-, IL-2, and IL-10 production were significantly higher in BALB/c mice. The levels of serum immunoglobulin E (IgE) and blood eosinophils in both mouse strains significantly increased between 3 and 6 weeks postinfection. Serum IgE levels were significantly higher in FVB mice than in BALB/c mice. The results of this study suggest that susceptibility to C. sinensis infection is associated with Th2 cytokine production, especially IL-4 which is predominant in relatively susceptible FVB mice.  相似文献   
46.
Currently, Korea is a low endemicity country for HAV, especially in children. However, recent reports of hepatitis A outbreaks show that there has been a shift of disease incidence to adolescents and young adults, with 2 cases of acute liver failure in one reported outbreak. We need to study the immune status for HAV in order to provide information for the establishment of preventive measures and possible consequences of HAV in Korea. A total of 334 infants, children and adolescents less than 20 years of age living in rural areas of Kyonggi Province, Korea were evaluated for anti-HAV immune status in 1996. Five hundred and eighty-four primary school children living in the same area were separately evaluated for the natural seroconversion rate between 1993 and follow-up samples taken in 1996. Anti-HAV IgG antibody was measured by enzyme immunoassay (HAVAB EIA kit, Abbott Laboratories, Chicago, Illinois, USA). In comparison with previous reports of seroprevalence rates, our data confirmed a dramatic drop in seroprevalence rates among children and adolescents under 20 years of age living in rural areas, from over 63.8% two decades ago to 4.6% in 1996. Natural acquisition of HAV antibody in primary school children rarely occurs, registering only 0.5% during three years. Several outbreaks in young adults during 1996-1998 suggested that immunity against HAV in this population is so low that massive outbreaks are unavoidable. Teenagers and young adults, especially soldiers, who are likely to be exposed to contaminated food or water, would also have a greater risk of hepatitis A. Immunizing children with HAV vaccine as a routine schedule should also be considered in Korea in the future, particularly if the disease burden could be estimated and the cost-effectiveness of the vaccine could be proved.  相似文献   
47.
In order to test the hypothesis that specimens blocking with a neutralizing reagent below the cutoff of the Chlamydiazyme enzyme immunoassay represent infected patients, we used direct fluorescent-antibody staining for elementary bodies (EBs) and PCR to confirm results for cervical swabs collected from 55,963 women and urethral swabs or first-void urine (FVU) samples collected from 5,781 men attending physicians' offices in the Toronto, Canada, area. Within a grey zone arbitrarily selected to represent values up to 40% below the positive threshold of the test run, 134 cervical swabs, 44 urethral swabs, and 39 FVU specimens exhibited a blocking response ( > 50% reduction in signal). Three or more EBs were observed in each of 98 cervical swabs (73.1%), 38 urethral swabs (86.4%), and 21 FVU specimens (53.8%). Of the 36 cervical swabs with fewer than three EBs, 33 were PCR positive; the positive PCR results for male specimens were 6 of 6 urethral swabs and 17 of 18 FVU samples. Application of the blocking test to specimens negative in the Chlamydiazyme enzyme immunoassay but having optical densities within 40% of the cutoff added 14.2% (217 of 1,531 specimens) more positive results to the survey. A total of 213 of 217 samples (98.2%) were reconfirmed as having EBs or DNA.  相似文献   
48.
Nonvascular intervention of the urinary tract is a well-established uroradiologic subspecialty, which is more important for avoiding invasive open surgery in the age of rising demand about the value of less invasive treatment. Various kinds of nonvascular intervention are recently performed under image-guidance and are as follows: percutaneous nephrostomy, percutaneous nephrostolithotomy, percutaneous dilatation of the urinary tract, sclerotherapy for renal cysts, percutaneous catheter drainage, percutaneous foreign body retrieval and biopsy. Percutaneous nephrostomy is a basic technique to provide a direct access to urinary tract, which makes it possible to perform other interventional procedures. Although nonvascular intervention may produce some complications, it is generally considered to be less invasive than open surgery and has advantages such as short hospital stay, early return to normal life and therefore economic savings. This review is described to help clinicians easily understand the procedures, indications, techniques, and complications with figures of cases the authors experienced.  相似文献   
49.
The effect of volume reduction on vasoactive substances and their role in estimating dry weight in haemodialysis patients was studied. Plasma atrial natriuretic peptide (ANP), catecholamines, antidiuretic hormone, renin activity and serum aldosterone were measured in 12 patients before and after bicarbonate haemodialysis. Haemodynamical changes were registered and cardiac function and diameter of the inferior vena cava were measured by echocardiography before and after dialysis. Plasma concentration of ANP was significantly reduced by haemodialysis from 209 +/- 51 to 69 +/- 13 pg mL(-1) (n = 12, P < 0.05), whereas concentrations of the other hormones were unchanged. The change in the concentration of ANP did not have significant correlation with weight reduction. The concentration of ANP correlated positively with the diameter of the inferior vena cava (r = 0.70, P < 0.05) after dialysis, but not before dialysis. The concentration of ANP before or after haemodialysis or its change during dialysis did not correlate with any other biochemical parameter. The results show that plasma ANP level is decreased after volume reduction in patients with chronic renal failure, whereas other hormonal systems are unresponsive. However, plasma concentration of ANP seems to have no role in estimating dry weight in chronic haemodialysis patients.  相似文献   
50.
CONTEXT: Soft tissue sarcomas constitute a heterogeneous group of tumors for which tumorigenesis is not fully understood. Altered cell-cycle regulation may underlie the development and/or progression of human malignancies. However, data concerning the occurrence of cell-cycle aberrations in soft tissue sarcomas are very limited. OBJECTIVES: To detect the abnormal features of cell-cycle regulatory proteins in soft tissue sarcomas and to determine the potential role of these proteins in clinical behavior. DESIGN: The p53 and Rb-cyclin D pathways were investigated by immunohistochemical studies of p53, mdm2, pRb, p16, cyclin D1, and cdk4 proteins, respectively. RESULTS: Of the 67 sarcomas analyzed, nuclear accumulation of p53 was detected in 25 samples (37%), and overexpression of mdm2 was found in 16 samples (24%). Both p53 and mdm2 expression correlated with tumor grade. Abnormalities involving the Rb-cyclin D pathway were identified in all of the tumors by the altered expression of either pRb (72%) or p16 (94%). Fourteen (21%) and 64 (96%) cases demonstrated cyclin D1 or cdk4 expression, respectively. Overexpression of cyclin D1 showed an association with pRb and p53. There was no correlation between pRb, p16, cyclin D1, or cdk4 and tumor grade or relapse. CONCLUSION: Disturbance in the cell-cycle regulatory system involving the p53 pathway and the Rb-cyclin D pathway is relatively frequent in soft tissue sarcomas and may be a contributing factor in the tumorigenesis of these tumors. The alterations in the Rb-cyclin D pathway probably constitute an early event, whereas the abnormalities in the p53 pathway seem to be involved in tumor progression. It is noteworthy that cyclin D1 may play a key role in linking both pathways.  相似文献   
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