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1.
SUMMARY: Inhibition of mevalonate synthesis by several statins has been shown to suppress DNA synthesis in glomerular mesangial cells. In the present study, we investigated the effect of a new statin, cerivastatin, on fetal calf serum (FCS)-induced DNA synthesis of cultured rat mesangial cells. Cultured rat mesangial cells were stimulated by 10% FCS in the presence or absence of cerivastatin and mevalonate. 5-bromo-2-deoxyuridine (BrdU) incorporation was used to assess DNA synthesis. the present study showed that 10% FCS caused marked stimulation of DNA synthesis in the mesangial cells. Cerivastatin inhibited FCS-stimulated BrdU incorporation in a dose-dependent manner. IC50 was approximately 1 umol/L. Exogenous mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate significantly prevented the inhibitory effect of cerivastatin on DNA replication. It appears that cerivastatin, by inhibiting the synthesis of mevalonate, may suppress DNA synthesis in the mesangial cells.  相似文献   
2.
We report on two cases of women with locally advanced squamous cell carcinoma of the urethra. Patient 1 also displayed regional lymph node metastasis. Treatment comprised combined radiotherapy to 60 Gy and chemotherapy with 5-fluorouracil and cisplatin. Complete response was obtained in both patients, including the inguinal lymph nodes of Patient 1. Patient 1 experienced recurrent inguinal lymph node metastasis on the contralateral side at 42 months after initial treatment, and the same treatment was performed followed by surgical excision. Both patients remain alive with no evidence of disease, at 12 months after recurrence in Patient 1, and at 27 months after treatment in Patient 2.  相似文献   
3.
We report the case of a female patient with bilateral metachronous adrenocortical cancer who survived long-term after adrenalectomy. In 1991, the patient underwent left adrenalectomy to remove a huge adrenal mass (10 x 9 cm) displaying no hormonal abnormality. Histological diagnosis was adrenocortical cancer. A right adrenal mass (7 x 6 cm) was found 4 years after left adrenalectomy. Right adrenalectomy was performed, and histological diagnosis was again adrenocortical cancer. The patient remains alive with no evidence of disease 8 years after last surgery.  相似文献   
4.
A sesquiterpenoid, 7-hydroxy-3,4-dihydrocadalin, isolated from a Mexican medicinal plant Heterotheca inuloides was evaluated as an antioxidant. This sesquiterpenoid inhibited mitochondrial and microsomal lipid peroxidation induced by Fe(III)-ADP/NADH or Fe(III)-ADP/NADPH. Furthermore, 7-hydroxy-3,4-dihydrocadalin protected red cells against oxidative haemolysis. This sesquiterpene was thus shown to be effective in protecting biological systems against oxidative stresses.  相似文献   
5.
PROBLEM : To determine if patients with unexplained recurrent miscarriage have a deficiency of decidual immunosuppressor cells that produce transforming growth factor β type 2, as has been found in mice with abortion due to rejection and/or trophoblast failure. METHODS : Decidual biopsy specimens were taken as near to the placental attachment site as possible under ultrasound guidance from first trimester legal termination (control) patients with recurrent miscarriage and non-viable pregnancy, and from patients with sporadic missed abortion. The tissue was tested for TGFβ-2+ suppressor cells by in situ hybridization, immunohistochemistry, and analysis of supernatants. RESULTS : TGFβ-2-related suppressor molecules similar but not identical to those identified in pregnant mice were released by decidual lymphoid cells. Fifty percent of 14 recurrent miscarriage patients showed a lack of suppressor cells and 59% were subnormal in comparison to 20 controls and 5 sporadic miscarriage patients, where 80–85% of the patients had detectable suppressor cells. CONCLUSIONS : Suppressor cell deficiency is compatible with a role for rejection and/or trophoblast failure in some patients with recurrent miscarriage. Presence of suppressor cells in most patients with missed abortion (4/5) is compatible with an alternative cause of fetal death, similar to findings reported in genetic fetal death mice.  相似文献   
6.
Abstract This study investigated interactions between mucosal lesions and bacterial invasion in ulcerative colitis using the acridine-orange staining method. In all 16 cases of ulcerative colitis, the mucosa was found to be invaded by small rods and cocci. In five of 10 controls, bacteria were seen only adhering to the mucosa and no bacteria were detected in the five remaining cases. It is suggested that the presence of bacteria in the colonic mucosa may be a factor responsible for the persistence or aggravation of ulcerative colitis.  相似文献   
7.
FK070, a thromboxane A2 (TXA2) receptor antagonist/TXA2 synthetase inhibitor, was given orally to healthy male volunteers in a single-and multiple-dose study. In the single-dose study (200, 300, 400 mg), the area under the plasma concentration—time curve (AUC) and the maximum plasma concentration (Cmax) increased non-linearly with dose, while the mean elimination half-life (t1β) was essentially unchanged (3.9-7.3 h). Recovery of the unchanged drug in the urine was 12–25%. Cmax and AUC as determined with 200 mg of drug after a meal decreased by about 60 and 30%, respectively. Ex-vivo platelet aggregation in the plasma by a TXA2 analogue, U46619, was almost completely inhibited within 1 h, after all doses of drug, with a significant dose-dependent inhibition maintained for 8 h or more, which was much longer than was expected from drug plasma concentration. The aggregation by adenosine diphosphate (ADP) was inhibited to a lesser extent. FK070 also inhibited TXA2 synthetase as evidenced by decreased production of TXB2 and reciprocally increased production of 6-keto-prostaglandin F in the serum during ex-vivo whole blood coagulation. These effects peaked 1 h after drug and lasted until 4 h with the higher doses. In the multiple-dose study (300 mg, twice a day, after meals for 6.5 days), drug concentrations in the plasma were well fitted to a three-compartment open model with first-order absorption. FK070 afforded extensive inhibition of platelet aggregation by U46619 throughout the administration period, with a significant inhibition lasting as long as 48 h after conclusion of administration. No clearly drug-related changes were found in routine laboratory tests, subjective and objective findings, or vital signs. FK070 was concluded to be well tolerated and to provide long-lasting blockade of TXA2 receptors, and plasma concentration-dependent inhibition of TXA2 synthetase in the platelets.  相似文献   
8.
The effect of cimetidine on the natural killer (NK) activityof peripheral blood lymphocytes (PBL) of 32 patients with ovariancarcinoma was studied before and after surgery or chemotherapy.There was no significant difference in the NK activity betweennormal healthy women and patients who had been disease-freefor more than a year after initial surgery, while those in patientswith a large residual tumor after surgery were profoundly suppressed.Cimetidine stimulated the NK activity in the disease-free patientsin vivo or in Vitro. In addition, cimetidine augmented the responseto phytohemagglutinin of PBL from the disease-free patients.The NK activity of PBL of patients with a large residual tumorunder chemotherapy consisting of cisplatinum, adriamycin andcyclophosphamide, "CAP," was about half of that before initiationof chemotherapy. The inhibition of the NK activity by chemotherapywas abrogated by in vitro exposure of the PBL to cimetidine.  相似文献   
9.
A case of "sclerosing hemangionia" (pneumocytoma) of the lungwith lymph node metastasis is reported. A 22-year-old Japaneseman was found to have a well-defined round lesion in the rightlung (S7), which increased in size slightly during a 2-yearfollow-up period. He underwent right lower lobectomy with a preoperative diagnosisof a benign lung tumor. The pulmonary tumor revealed histologicalfeatures characteristic of "sclerosing hemangioma" of the lung,in addition to which there were many large polygonal foamy cells,forming tubular or papillary structures. These cells were foundby electron microscopy to contain numerous cytoplasmic lamellarbodies and showed a positive reaction with anti-surfactant apoproteinantibody immunohistochemically. Therefore, they were consideredto be cells differentiating toward type II pneumocytes. Reviewof 21 typical "sclerosing hemangionia" disclosed a few or somesuch foamy cells in 10 cases. A single hilar lymph node wasthe site of microscopic metastases, which consisted of "largeclear foamy cells" and smaller polygonal or round cells withslightly eosinophilic cytoplasm, both of which were componentsof the pulmonary "sclerosing hemangioma" This case supportsthe theory that "sclerosing hemangioma" is a neoplasm of typeII pneumocyte lineage. Although it is said to be benign, rarecases apparently show metastatic potential.  相似文献   
10.
Cathepsin D and epidermal growth factor receptor (EGFR) antigens are related to tumor invasion, metastasis, progression, and recurrence. To assess the prognostic significance of the expression of these two antigens, biopsy specimens consecutively obtained from 216 patients with stage III cervical carcinomas (191 with squamous cell carcinomas and 25 with adenocarcinomas), who were treated with radiotherapy, were investigated immunohistochemically. The positive rate of cathepsin D expression in squamous cell carcinomas was 74%, significantly higher than the 47% observed in adenocarcinomas ( P  = 0.015). The EGFR positive rate in squamous cell carcinomas was 33%, somewhat higher than the 16% in adenocarcinomas ( P  = 0.088). The chi-square test and Kaplan–Meier method showed no significant relationship between the expression of either cathepsin D or EGFR and the prognosis in these patients. These results indicate that in stage III cervical carcinomas cathepsin D and EGFR expression do not correlate with prognosis.  相似文献   
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