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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   
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Aims:


The purpose of this study is to examine the relationship between immunohistochemical localization of cathepsin D (CD), proliferating cell nuclear antigen (PCNA) and epidermal growth factor receptor (EGF-R) in 65 cases of breast carcinoma in Japanese women and traditional prognostic factors such as histological grade, lymph node status, mitotic rate and clinical stage, in order to possibly identify some indicator(s) that may be specifically associated with prognosis.  

Methods and results:


Serial sections of 5-μm thick were cut from the archival formalin-fixed, paraffin-embedded tissue blocks, and processed for CD, PCNA and EGF-R immunostaining. The results were analysed by computer-based image analysis system. All samples showed a positive immunoreaction for cathepsin D in both the parenchyma and stroma. However, the staining area and intensity varied from cell to cell in the parenchyma and stroma as well as among samples. Subsequently, the evaluation of immunostaining for CD was separately performed in both the parenchyma and stroma (CDpar and CDstr, respectively) and the combination of both components (CDtotal). PCNA and EGF-R showed positive immunostaining almost exclusively in the parenchymal component of the carcinoma tissue specimens. CDtotal significantly correlated with the histological grade, PCNA index (PI), mitotic rate (MR), EGF-R and lymph node metastasis. Significant correlation was also demonstrated between CDpar and the histological grade, EGF-R and lymph node metastasis, or between CDstr and MR, EGF-R and lymph node metastasis. EGF-R correlated highly with the histological grade, MR score, lymph node metastases and recurrence-free survival.  

Conclusions:


Both the CD parameters and EGF-R are valuable indicators for predicting the biological behaviour of human breast carcinoma.  相似文献   
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Quality of ulcer healing influences the relapse of gastric ulcers in humans   总被引:8,自引:0,他引:8  
The usefulness of dye-contrast endoscopy for the evaluation of the quality of gastric ulcer healing and the prediction of relapse was investigated. Sixty consenting patients whose ulcers healed during 3 months of treatment underwent endoscopy for the identification of the pattern of mucosal regeneration. Patients were monitored for relapses for up to 18 months after antiulcer therapy had ended. The pattern of regeneration was flat in 24 patients, nodular in 25 and intermediate in 11. Internal hypoechoic areas seen by endoscopic ultrasonography were less common and histological maturity was better in the patient group with the flat pattern compared with the patient group with the nodular pattern of mucosal regeneration. Prostaglandin E, synthesis was highest in the group with the flat pattern of mucosal regeneration and the relapse rate was lowest in this group. We conclude that the evaluation of the quality of ulcer healing is possible and that findings in individuals may aid the prediction of relapse for particular patients.  相似文献   
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Background: Progression of the core and accessory symptoms of dementia can be slowed if drug therapies and psychosocial interventions are administered at an early stage. The aim of this study was to develop and standardize a neuropsychological test for the elderly that can detect dementia at an early stage with high sensitivity and can evaluate a wide range of severities of dementia based on assessments of various cognitive functions. Methods: A preliminary test consisting of 23 items and the Nishimura Mental State Scale for the Elderly (NM Scale), which evaluates the mental functions of elderly individuals by observing their actual behaviors in daily life, were administered to 448 elderly subjects. After applying Hayashi’s quantification theory type I to the results, we revised the preliminary test to construct a neuropsychological test for the elderly, which we named the Nishimura Dementia Test (ND Test), and standardized it. Then, we examined its validity and test–retest reliability. Results: Among the 448 subjects, there was a strong correlation between the ND Test scores and NM Scale scores. The ND Test showed a good general agreement rate for the discrimination of the severity of dementia, and good sensitivity and specificity of discrimination of dementia when compared with the actual NM Scale. Using different groups of elderly subjects, the ND Test showed validity and test–retest reliability, and the ND Test scores showed strong correlations with the Revised Hasegawa Dementia Scale scores and the Mini‐Mental State Examination scores. Conclusions: The ND Test is based on assessment of a variety of cognitive functions and can evaluate a wide range of severities of dementia with good validity and reliability.  相似文献   
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The roles of IgE and mast cells on expulsion of adult Hymenolepis nana from the intestine were examined in mice. IgE-dependency was determined by comparing congenitally IgE-deficient SJA/9 and IgE-producing SJL/J mice infected with 50 H. nana eggs. Anti-H. nana IgE antibody was detected at three weeks post infection (p.i.) in SJL but not in SJA mice. The number of adult worms in the intestines of SJA and of SJL mice were similar at two weeks, but significantly more were found in SJA mice at three weeks p.i. Treatment of mice with anti-ɛ antibody also resulted in an increased worm burden at three weeks, suggesting participation of IgE in expulsion of H. nana. Intestinal mastocytosis was induced by infection regardless of the IgE status of the mice. Mast cell-dependency was tested in mast cell-deficient W/Wu and in normal littermate +/+ mice infected with 100 H. nana eggs. Anti-H. nana antibody was detected in both groups of mice at three weeks p.i. Worm expulsion seemed to be mast cell dependent because expulsion was less complete in W/Wu mice at three weeks p.i. Peripheral blood eosinophilia was comparable at three weeks p.i. in both IgE and mast cell sufficient and deficient mice. These results suggest that IgE and mast cells participate in the expulsion of H. nana adults from intestine in mice.  相似文献   
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A female infant with nesidioblastosis who showed mild clinical symptoms is reported. In this patient, insulin levels and insulin to glucose ratios (IRI/G) were often normal. Regular milk feedings supplemented with continuous glucose infusion (0.7-2 mg/kg per min) or oral glucose feedings (4.5 mg/kg per min) prevented hypoglycemia. As leucine-sensitivity was diagnosed at 2 months of age, she was started on diazoxide. This was, however, ineffective, and adverse effects appeared. Subtotal pancreatectomy (95%) was therefore attempted at 5 months of age, and persistent normoglycemia as well as normal growth and development followed up to 3 years after the operation. The pancreas showed characteristic signs of nesidioblastosis. The above clinical observation suggests that a patient with nesidioblastosis whose blood glucose level is easily controllable may develop an unexpected episode of hypoglycemia in the presence of a leucine sensitivity. In such a patient, diazoxide or, when it is of no avail, surgical intervention should promptly be instituted to prevent possible neurologic sequelae induced by hypoglycemia.  相似文献   
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