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1.
Background: Olfactory neuroblastoma is a rare sino‐nasal tumor arising from the olfactory epithelium and is often characterized by local invasion or metastasis. The role of chemotherapy in the treatment of this tumor is unclear. The purpose of this study was to review our institution’s experience of chemotherapy for advanced or recurrent olfactory neuroblastoma. Methods: Twenty‐one patients with histologically proven olfactory neuroblastoma were treated at our institution between 1992 and 2002. Twelve of these patients received chemotherapy in the setting of unresectable or recurrent disease and were retrospectively reviewed for clinical characteristics, treatment outcome or survival. Results: Eight patients of the 12 patients received cisplatin‐based chemotherapy and the remaining four patients received chemotherapy consisting of docetaxel plus irinotecan (three patients) or cyclophosphamide, doxorubicin, and vincristine (1 patient). A partial response was achieved in five patients, with an overall response rate of 42%, although the chemotherapeutic regimens were heterogeneous. Two partial responses were obtained among the three patients who received docetaxel plus irinotecan. The response rate to chemotherapy was 83% in the younger age group (<40 years), as opposed to 0% in the older age group (≥40 years), and the difference between the two groups was statistically significant (P = 0.02). Conclusion: Our study indicated that olfactory neuroblastoma would be sensitive to chemotherapy, especially with young patients. Docetaxel plus irinotecan has the possibility of showing favorable response, and warrants further investigation.  相似文献   
2.
Background and Aim:  We recently reported that cyclooxygenase (COX)-2 is upregulated in the rat small intestine after administration of indomethacin, and this may be the key to non-steroidal anti-inflammatory drug (NSAID)-induced intestinal damage. The present study investigated the mechanism for COX-2 expression induced in the rat small intestine by indomethacin, in relation with ulcerogenic processes.
Methods:  Animals were given indomethacin or SC-560 p.o., and the intestinal mucosa was examined 24 h later.
Results:  Indomethacin caused hemorrhagic lesions in the small intestine, accompanied with an increase in intestinal motility, bacterial invasion and inducible nitric oxide synthase (iNOS) activity, as well as the expression of COX-2 mRNA in the mucosa. Although SC-560 did not cause any damage, this agent caused intestinal hypermotility, the bacterial invasion and the upregulation of COX-2 expression. The mucosal PGE2 content was decreased by SC-560 at 3 h but recovered 12 h later, and this recovery of PGE2 was attenuated by both atropine and ampicillin, in addition to rofecoxib. The intestinal hypermotility response to indomethacin was prevented by both 16,16-dimethyl PGE2 and atropine, but not ampicillin. Yet all these agents inhibited not only the bacterial invasion but also the expression of COX-2 and iNOS activity in the intestinal mucosa following indomethacin treatment, resulting in the prevention of intestinal lesions.
Conclusion:  These results suggest that COX-2 expression in the intestinal mucosa following the administration of indomethacin is associated with intestinal hypermotility and bacterial invasion. The intestinal hypermotility caused by COX-1 inhibition may be a key to COX-2 expression after administration of NSAIDs and their intestinal ulcerogenic properties.  相似文献   
3.
BACKGROUND: High-intensity focused ultrasound (HIFU) is a minimally invasive technique used in achieve coagulation necrosis. We evaluated biochemical disease-free survival rates, predictors of clinical outcome and morbidity in patients with localized prostate cancer treated with HIFU. METHODS: A total of 181 consecutive patients underwent HIFU with the use of Sonablate (Focus Surgery, Indianapolis, IN, USA). Biochemical recurrence was defined according to the criteria recommended by the American Society for Therapeutic Radiology and Oncology Consensus Panel. The median age and pretreatment prostate-specific antigen (PSA) level were 70 years (range 44-88) and 9.76 ng/mL (range 3.39-89.60). A total of 95 patients (52%) were treated with neoadjuvant hormones. The median follow-up period for all patients was 18.0 months (range 4-68). RESULTS: The biochemical disease-free survival rates at 1, 3 and 5 years in all patients were 84%, 80% and 78%, respectively. The biochemical disease-free survival rates at 3 years for patients with pretreatment PSA less than 10 ng/mL, 10.01-20.0 ng/mL and more than 20.0 ng/mL were 94%, 75% and 35%, respectively (P<0.0001). Multivariate analysis identified pretreatment PSA (P<0.0001) as a independent predictor of relapse. CONCLUSION: High-intensity focused ultrasound therapy appears to be a safe and efficacious minimally invasive therapy for patients with localized prostate cancer, especially those with a pretreatment PSA level less than 20 ng/mL.  相似文献   
4.
Abstract  Although respiration in trained canines is well investigated, the process of preparing dogs has not been described in any great detail. Moreover, their daytime patterns of sleep and wakefulness during 1 or 2 h of electroencephalogram (EEG) and electrocardiogram (ECG) recordings are not clear. Therefore, we describe the process of selecting and training dogs, in which we recorded EEG and ECG in the laboratory. First, 14 of 1242 dogs dealt with over a 1 year period were chosen. They were trained for 2 h to lie quietly and to sleep in the laboratory; this training procedure was repeated 152 times. Three dogs were then selected and a permanent tracheostomy was performed in one. Finally, EEG and ECG were recorded with the bipolar fine needle electrodes; respiration was recorded simultaneously through a tube inserted to a tracheostomy in one dog. Wakefulness, slow wave sleep (SWS) and rapid eye movement (REM) sleep (REMS) were identified according to the EEG pattern and on the basis of the behavioral criteria. Recordings were performed 12 or 13 times in each dog. Complete sleep cycles, including wakefulness, SWS and REMS in this sequence, were observed 3.9–4.1 times. The mean duration of SWS was 2.2–4.4 min and that of REMS was 3.5–4.6 min. The REMS latency was 33.9–41.8 min. Fluctuation of heart rate with respiration, termed respiratory sinus arrhythmia, was noted in the ECG. Heart beat increased with inspiration and decreased with expiration. The present study demonstrates how to select and train sleeping dogs and shows their undisturbed daytime sleep and wakefulness patterns.  相似文献   
5.
6.
HtrA2 is up-regulated in the rat testis after experimental cryptorchidism   总被引:3,自引:0,他引:3  
AIM: The aim of the present study was to elucidate the role of high temperature requirement A2 (HtrA2) in germ cell loss in the heat-stressed testis. METHODS: We examined the expression of HtrA2, caspase-9 activity and proteolytic activity of HtrA2 in the rat testis, and their in vivo responses to experimental cryptorchid treatment. RESULTS: Northern analysis revealed the expression of HtrA2 mRNA peaked at days 1 and 7 after cryptorchid treatment. While expression of HtrA2 mRNA was seen in the spermatogonium, spermatocytes and some spermatids in normal adult rat testis, experimental cryptorchidism treatment resulted in a marked increase in its signal intensity in spermatocytes and some spermatids, and the layers of spermatogonium and early primary spermatocytes became negative at days 1 and 7 after the treatment. However, the spermatogonium, Sertoli cells and interstitial cells appeared to have strong intensities at days 14, 28 and 56 after the treatment. Western analysis revealed the expression of HtrA2 protein peaked at day 2 coinciding with the increase of positive spermatogonium, the appearance of protein-positive interstitial cells, and day 28 coinciding with the reappearance of protein-positive interstitial cells. Caspase-9 activity peaked at day 2 and HtrA2 proteolytic activity peaked at day 28. Consequently, the first peak of HtrA2 mRNA expression was followed by the peak of caspase-9 activity and the second peak was followed by the peak of proteolytic activity; however, the second peak of mRNA expression had considerable chronological difference from that of the protein. CONCLUSION: These findings suggest the probabilities that the heat stress results in germ cell death by a caspase-independent manner with the elevation of HtrA2 proteolytic activity, as well as a caspase-dependent manner with the elevation of caspase-9 activity.  相似文献   
7.
A 55‐year‐old‐man had a laparoscopic resection of the sigmoid colon due to colon cancer with submucosal invasion. After the surgery he suffered ileus and had a laparotomy. Six months later he complained of frequent defecation. Colonoscopy confirmed a circular ulcer extending from the anal side of the anastomosis in the sigmoid colon to the mid rectum. Endoscopic ultrasound demonstrated thickening of all layers of the diseased colon and rectum. We diagnosed ischemic colitis. After intravenous drip infusion of prostaglandin, symptoms and colonic stricture gradually improved. Although abdominal angiography revealed a narrowing of the peripheral sigmoid branch of the inferior mesenteric artery, blood flow was unrestricted. Colonoscopy performed 84 days after discharge revealed an ulcer scar.  相似文献   
8.
To clarify the pathogenesis of the widely known but obscuresyndrome of sudden death with hepatic fatty metamorphosis observedin alcohol abusers, we have scrutinized both the clinical andpathological data of 11 subjects who died under such circumstancesbetween 1987 and 1993. Death followed several days of uninterrupteddrinking often with little dietary intake. The notable clinicalfeatures on arrival at the emergency room were disturbance ofconsciousness (11/11), hypotension (47/6), hypothermia (3/5),hypoglycaemia (8/11), metabolic acidosis (6/6), renal dysfunction(11/11), and hyperammonaemia (5/5). The common hepatic pathologywas the extensive appearance of numerous microvesicular fattydroplets in the hepatocytes together with varying degrees ofmacrovesicular fatty change; four subjects had an underlyingcirrhosis. Death undoubtedly results from a variety of metabolicdisturbances triggered by the combination of massive ethanolintake and starvation. The appearance of extensive microvesicularfatty change superimposed on macrovesicular fatty change wasconsidered to be an associated phenomenon  相似文献   
9.
The importance of oxygen in maintaining the functional integrity of hepatocytes has been well established in a variety of experimental models, such as in vivo , perfused liver and isolated hepatocytes. However, one of the shortcomings of these systems is their short life span. Therefore, we have examined the effects of long-term hypoxia on cellular adenine nucleotide content and cellular functions, such as albumin production, urea production and DNA synthesis, in adult rat hepatocytes in primary culture. Hepatocytes were cultured at a density of 11 × 104 and 5 × 104 cells/0.18 mL per cm2 for the study of albumin and urea production and DNA synthesis, respectively, at various oxygen tensions (20, 12, 8 and 5%) for 24 h. Cellular ATP content in cultured hepatocytes in hypoxia gradually declined, corresponding to the decrease in oxygen tension, and the cellular ATP level at 5% oxygen was approximately 20% of that at 20% oxygen. Albumin production also decreased in parallel with the decrease in cellular ATP content in cultured hepatocytes in hypoxia. However, even when cellular ATP content gradually declined corresponding with the decrease in oxygen tension in cultured hepatocytes in hypoxia, such as at 8 or 5% oxygen, urea production remained at a high level; in contrast, DNA synthesis was completely suppressed. These results suggest that the cellular ATP content decreases in cultured hepatocytes during long-term hypoxia in relation to oxygen tension and that the relationship between decreased ATP levels and liver function in cultured hepatocytes during hypoxia differs for albumin production, urea production and DNA synthesis.  相似文献   
10.
The vacuolating cytotoxin and urease secreted by Helicobacter pylori are thought to be virulent factors. Because vacuolation is potentiated by the presence of ammonium ion, which is produced by urease in vitro, it is of interest to examine whether cytotoxin and urease work reciprocally in the development of atrophic gastritis or duodenal ulcer. In the present study, patients (all H. pyloripositive) were divided into four groups: mild atrophic gastritis (group 1; nine patients), severe atrophic gastritis (group 2; 36 patients), duodenal ulcer with mild atrophic gastritis (group 3; 19 patients) and duodenal ulcer with severe atrophic gastritis (group 4; 12 patients). Cytotoxin production and urease activity of H. pylori isolated from these patients were analysed. Cytotoxin production was observed in four of nine (44.4%), 28 of 36 (77.8%), 11 of 19 (57.9%) and eight of 12 (66.7%) isolates from groups 1, 2, 3 and 4, respectively. Cytotoxin-producing H. pylori isolates were found significantly more in patients with severe atrophy than in patients with mild atrophy (P= 0.048). The mean of relative activity of cytotoxin in H. pylori isolate was 1. 6. ± 2. 3, 7. 9. ± 7. 4, 5. 8. ± 6. 0 and 9. 0 ± 9. 1 in groups 1, 2, 3 and 4, respectively. Helicobacter pylori isolates from severe atrophy or duodenal ulcer patients in groups 2 or 4 possessed significantly higher activity than those from non-ulcer patients in group 1 (P= 0.017 and 0.030, respectively). The mean of urease activity was 8. 6 ± 4. 6, 10. 0 ± 5. 9, 10. 0 ± 8. 5 and 11. 2 ± 7. 7 IU/mg in groups 1, 2, 3 and 4, respectively. These differences indicated no statistical significance. In each H. pylori isolate, the production of cytotoxin and urease were independent, which indicated that there was no reciprocal effect between them in vivo. Thus, cytotoxin-producing H. pylori isolates were more prevalent in patients with severe atrophic gastritis and the cytotoxin activities of H. pylori isolates from the patients with severe atrophic gastritis or duodenal ulcer were much higher than those from the patients with mild atrophic gastritis, which suggested that vacuolating cytotoxin may be a disease-inducing factor.  相似文献   
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