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排序方式: 共有874条查询结果,搜索用时 15 毫秒
61.
Azithromycin reverses anticancer drug resistance and modifies hepatobiliary excretion of doxorubicin in rats 总被引:3,自引:0,他引:3
Asakura E Nakayama H Sugie M Zhao YL Nadai M Kitaichi K Shimizu A Miyoshi M Takagi K Takagi K Hasegawa T 《European journal of pharmacology》2004,484(2-3):333-339
The present study aims to investigate whether azithromycin reverses P-glycoprotein-dependent anticancer drug resistance in vitro and modifies the hepatobiliary excretion of doxorubicin, a substrate for P-glycoprotein in vivo. Azithromycin increased dose-dependently the intracellular accumulation of doxorubicin in adriamycin-resistant human myelogenous leukemia cells (K562/ADR) with no effect on the expression of P-glycoprotein in the cells. However, the inhibitory effect was much weaker than that of cyclosporin A and was comparable to that of erythromycin. When Sprague-Dawley (SD) rats, which have drug transporting P-glycoprotein and multidrug resistance-associated protein 2 (Mrp2) in the bile canalicular membrane of hepatocytes, received an infusion of doxorubicin, the steady-state biliary clearance of doxorubicin was significantly decreased for 40 min after a single intravenous injection of azithromycin. However, azithromycin did not increase the plasma concentration of doxorubicin. The biliary clearance of doxorubicin in Eisai hyperbilirubinemic rats (EHBRs), which have a hereditary deficiency in Mrp2, was significantly decreased compared with that in Sprague-Dawley rats, suggesting the involvement of Mrp2 in the biliary excretion of doxorubicin. The present findings suggest that azithromycin overcomes P-glycoprotein-dependent anticancer drug resistance of tumors by inhibiting the binding of doxorubicin to P-glycoprotein in K562/ADR cells and inhibits the hepatobiliary excretion of drugs that are substrates for P-glycoprotein and Mrp2. 相似文献
62.
Morita S Toi M Kobayashi T Ito Y Hozumi Y Ohno S Iwata H Sakamoto J 《Japanese journal of clinical oncology》2004,34(2):104-106
A phase I clinical trial was started in order to determine the recommended doses of capecitabine and epirubicin, when administered in combination with a fixed dose of cyclophosphamide (600 mg/m(2) day 1 q3 weeks) in patients with inoperable or recurrent breast cancer. This study consists of five dose levels with combinations of three levels of epirubicin (75, 90 and 100 mg/m(2) day 1 q3 weeks) and three levels of capecitabine (1255, 1657 and 1800 mg/m(2)/day consecutive administration for 2 weeks followed by 1 week of rest). Dose escalation and de-escalation decisions are based on a continual reassessment method (CRM). We conducted a survey of the clinical oncologists participating in this trial to determine the dose escalation/de-escalation rule, including a prior distribution for model parameters used in the CRM. 相似文献
63.
Ewing's sarcomas account for 6.8% of all primary malignant bone tumors and are probably a neurogenic, undifferentiated, high-grade malignancy, which usually affects the bones of children 5-15 years of age. Pain and swelling are the most common symptoms. Increase of CRP and erythrocyte sedimentation rate, leucocytosis, and anemia are frequently seen. Radiologically, they show permeative bone destruction on plain radiographs. When arising in the diaphysis of long bones, laminated, "onion-skin" periosteal reaction is seen. The tumor shows muscle density on CT, iso-signal intensity on T1-weighted MR images, and high signal intensity on T2-weighted MR images. Intramedullary invasion and skip lesions can be detected on MR images. Histologically, the tumor is uniformly composed of sheets of small round cells closely packed and without any matrix product. Glycogen granules are demonstrated in the cytoplasm by periodic acid-Schiff (PAS) and diastase reactions. Immunohistochemically, Ewing's sarcomas are positive for vimentin and MIC-2 gene product (CD99). Reciprocal translocation, i.e., t(11;22) (q24;q12), is seen in the tumor cells. EWS/FLI-1 fusion gene can be demonstrated, which can be a complementary method in diagnosing this tumor. Because Ewing's sarcomas are chemosensitive and radiosensitive, they are treated by a combination of chemotherapy, surgery, and radiotherapy. Neoadjuvant chemotherapy consists of preoperative chemotherapy and postoperative chemotherapy. Preoperative chemotherapy aims at eradicating distant micrometastasis, reducing the primary tumor volume, and evaluating the efficacy of the chemotherapeutic agents. Surgery is performed as a local treatment by excising the tumor using the wide procedure. If surgery is impractical, curative radiotherapy is performed instead of excision. When surgery is performed without complete wide procedure, adjuvant radiotherapy is carried out to eradicate the residual tumor cells. Postoperative chemotherapy aims to eradicate the distant micrometastasis. Recently, myeloablative, high-dose chemotherapy followed by autologous bone marrow transplantation is being attempted for poor-prognosis patients and good results have been reported. 相似文献
64.
Kimura T Kamiura S Komoto T Seino H Tenma K Ohta Y Yamamoto T Saji F 《European journal of obstetrics, gynecology, and reproductive biology》2003,108(2):213-216
OBJECTIVE: The aim of this study was to analyze the clinical and imaging characteristics in patients diagnosed with atypical endometrial hyperplasia based on endometrial biopsy in comparison with the final diagnosis from resected uteri; i.e. to determine the rates of underestimation (endometrial cancer), equivalent diagnosis (atypical hyperplasia), and overestimation (hyperplasia without atypia or non-hyperplastic lesion). MATERIALS AND METHODS: We reviewed 33 patients who were diagnosed with atypical endometrial hyperplasia by endometrial biopsy using a small curette and then underwent total abdominal hysterectomy between September 1992 and May 2002. Clinical parameters obtained from patients' charts, and imaging analyses using transvaginal ultrasonography (TUS) and magnetic resonance (MR) imaging were retrospectively re-examined. RESULTS: Among 33 patients who underwent hysterectomy due to a diagnosis of atypical hyperplasia, nine cases (27.2%) were underestimated (cancer), nine cases (27.2%) were equivalent and 15 cases (45.6%) were overestimated as indicated by examination of the endometrium of the resected uterus. There was no difference among these groups in either clinical parameters or diagnostic images obtained by TUS or MR. CONCLUSION: Diagnosis of atypical endometrial hyperplasia by endometrial biopsy often resulted in under- or over-estimation, as shown by examination after hysterectomy. As there is neither a reliable clinical parameter nor imaging feature to distinguish between these groups, hysterectomy is still the best treatment for these patients if they are willing to give up their fertility. 相似文献
65.
Sequence variability and candidate gene analysis in two cancer patients with complex clinical outcomes during morphine therapy. 总被引:8,自引:0,他引:8
Takeshi Hirota Ichiro Ieiri Hiroshi Takane Hiroyuki Sano Katsuyuki Kawamoto Hironao Aono Akira Yamasaki Hiromi Takeuchi Mikio Masada Eiji Shimizu Shun Higuchi Kenji Otsubo 《Drug metabolism and disposition》2003,31(5):677-680
In this case report, we present genetic differences in two morphine-related gene sequences, UDP-glucuronosyltransferase 2B7 (UGT2B7) and mu opioid receptors (MOR1), in two cancer patients whose clinical responses to morphine were very different [i.e., sensitive (patient 1) and low responder (patient 2)]. In addition, allelic variants in the UGT2B7 gene were analyzed in 46 Japanese individuals. Amplified DNA fragments for the two genes of interest were screened using single strand conformation polymorphism and then sequenced. In the UGT2B7 gene, 12 single nucleotide polymorphisms (SNPs) were newly identified with an allelic frequency ranging from 0.022 to 0.978. Six SNPs in the promoter region (A-1302G, T-1295C, T-1111C, G-899A, A-327G, and T-125C) and two coding SNPs (UGT2B7*2 in exon 2 and C1059G in exon 4) appeared to be consistently linked. Remarkable differences in the nucleotide sequence of UGT2B7 were observed between the two patients; in contrast to patient 1 who had "reference" alleles at almost SNP positions, but a rare ATTGAT*2(AT)C haplotype as homozygosity, patient 2 was a homozygous carrier for the predominant GCCAGC*1(TC)G sequence. Serum morphine and two glucuronide concentrations in patient 2 suggest that the predominant GCCAGC*1G sequence was not associated with a "poor metabolizer" phenotype. In the MOR1 gene, patient 1 had no SNPs, whereas patient 2 was a heterozygous carrier for both the G-1784A and A118G alleles. The present study describes substantial differences in genotype patterns of two genes of interest between the two patients. The results necessitate larger trials to confirm these observations in larger case control studies. 相似文献
66.
Flt-4-positive vessel density correlates with vascular endothelial growth factor-d expression, nodal status, and prognosis in breast cancer. 总被引:8,自引:0,他引:8
Yasushi Nakamura Hironao Yasuoka Masahiko Tsujimoto Qifeng Yang Shigeru Imabun Masaaki Nakahara Kazuyasu Nakao Misa Nakamura Ichiro Mori Kennichi Kakudo 《Clinical cancer research》2003,9(14):5313-5317
PURPOSE: Metastasis to the regional lymph nodes through the lymphatic vessels is a common step in the progression of cancer and an important prognostic factor in many types of cancer. Recent evidence suggests that tumor lymphangiogenesis promotes lymphatic metastasis, and that the presence of Flt-4 on tumor blood and lymphatic vessels may play a important role in mediating lymphangiogenic factor-induced neovascularization. We assessed flt-4-positive vessel density (FVD) in breast cancer, and examined whether FVD associates with lymph node metastasis, VEGF-D expression, or prognosis. EXPERIMENTAL DESIGN: One hundred three invasive breast carcinomas with long-term follow-up were included in our study. Flt-4 was assessed using immunohistochemistry, then we analyzed the relationship between FVD and lymph node status, as well as VEGF-D expression and other established clinicopathological parameters. The relationship between FVD and prognosis was also investigated. RESULTS: Mean FVD of "hot spot" was 29.3 +/- 22.5 for each case. FVD was correlated significantly with lymph node metastasis (P < 0.0001), VEGF-D expression (P = 0.0019), tumor size (P = 0.0015), estrogen receptor (P = 0.0211), progesterone receptor (P = 0.0462), and c-erbB-2 (P = 0.0326). Survival curves determined by the Kaplan-Meier method and univariate analysis demonstrated that high FVD was associated with both worse disease-free survival (P = 0.0035) and overall survival (P = 0.0336). CONCLUSIONS: Increased FVD was correlated with lymph node metastasis and VEGF-D expression. High FVD may be a significant unfavorable prognostic factor for long-term survival in breast cancer. It is possible that Flt-4 becomes a target for antiangiogenic therapy to breast cancer. 相似文献
67.
Tadano T Hozumi M Satoh N Oka R Hishinuma T Mizugaki M Arai Y Yasuhara H Kinemuchi H Niijima F Nakagawasai O Tan-no K Kisara K 《Pharmacology》2001,62(3):157-162
Intraperitoneal injection of benzodiazepine receptor agonists (estazolam, zopiclone, triazolam: 0.03-0.24 mmol/kg) induces the head twitch response (HTR). The present study was undertaken to examine the possible participation of the serotonergic system in the mechanism of head twitches induced by benzodiazepine receptor agonists (BZ-RAs). The HTR induced by BZ-RAs was suppressed by pretreatment with ketanserine (1 mg/kg, i.p.), a selective 5-HT(2) receptor antagonist. Pretreatment with fluoxetine (10 mg/kg, i.p.), a 5-HT reuptake inhibitor, and 8-hydroxy-2-(di-n-propylamino)tetralin, a 5-HT(1A) receptor agonist, also suppressed the HTR induced by BZ-RAs. These results suggest that the HTR induced by BZ-RAs may be the result of an activation of postsynaptic 5-HT(2) receptors, probably due to direct action. 相似文献
68.
Shigeki TOKUNAGA Takayoshi IKEDA Takeshi MATSUO Hiroshi MAEDA Nobuko KUROSAKI Hozumi SHIMODA 《Congenital anomalies》1986,26(4):321-330
Abstract A case of sacral parasite is presented. A parasitic body with an incomplete lower limb was attached to the sacrococcygeal region of a female newborn at birth. The twins were easily separated by operation two days after birth. The parasite contained well developed small and/or large intestines, a multilocular cyst and a unilocular cyst. Histologically, the wall of the multilocular cyst consisted of tissues of three germ layers, such as central and peripheral nervous tissues, mature and immature intestine, pancreatic tissue, bronchial cysts, connective tissue, etc. The thick wall of the unilocular cyst consisted of central nervous tissue and connective tissue. The degree of differentiation of these tissues varied considerably. The parasite revealed no organ communication with the autosite. Since the operation, her growth and development have been favorable and no other abnormalities have been found. 相似文献
69.
Y Kanzaki K Yoshida T Hozumi T Akasaka T Takagi Y Yonezawa T Yagi S Morioka H Ito H Yoshioka M Nishiura M Watanabe J Yoshikawa 《Journal of cardiology》1999,34(4):207-210
Recent development of an automated contour tracking (ACT) method using the energy minimization principle provides automated edge detection and tracking of the endocardial boundary of the left ventricle, without tracing a region of interest. This study determined whether left ventricular filling indexes obtained from the ACT method provide a reliable estimate of left ventricular diastolic filling. Fourteen patients were examined by the ACT method and equilibrium radionuclide ventriculography. The volume-time wave form for ACT measurements was obtained from the 4-chamber views. Peak filling rate and time to peak filling rate measured by the ACT method were compared with those determined by radionuclide ventriculography. Peak filling rate and time to peak filling rate by the ACT method were closely correlated with those determined by radionuclide ventriculography (peak filling rate: r = 0.88, y = 0.71x + 0.36, SEE = 0.54 ml/end-diastolic volume/sec, time to peak filling rate: r = 0.89, y = 0.72x + 30.0, SEE = 0.02 msec, respectively) The ACT method is useful for the assessment of left ventricular diastolic filling. 相似文献
70.
E Matsuura T Nemoto H Hozumi K Izumi Y Saito H Ishida T Fukimbara H Kawahara 《The Kitasato archives of experimental medicine》1991,64(4):193-204
In order to determine effects of iron deficiency on the living body, rats were given the iron deficient diet (Group 1, iron content, 0.32mg/100g), the complete diet added with iron (Group 5, iron content, 32.5mg/100g), the diet added with 1% chlorella (Group 2, iron content, 2.2mg/100g), the diet added with 5% chlorella (Group 3, iron content, 7.4mg/100g), or the diet added with 10% chlorella (Group 4, iron content, 13.9mg/100g). For the first 30 days, rats of all groups were given the iron deficiency diet to make them iron deficient, and were subsequently given the respective diet during the next 30 days to observe various changes in the conditions of rats. Following results were obtained. 1) When rats were reared for 30 days with the iron deficient diet, rats of these groups became anemic and their hemoglobin concentrations and hematocrit values lowered. Rats of Groups 3, 4 and 5 fed with the diets containing certain amounts of iron rapidly recovered, while the recovery of those of Group 2 fed with less iron content diet was delayed. Group 1 fed with the iron deficient diet showed no recovery. 2) Examination of effects of these diets on the rats body weight gains revealed that the growth of Groups 1 and 2 with iron deficiency was delayed notably (p less than 0.01) as compared with Group 5 and that of Group 3 was likewise restrained (p less than 0.05). The relative organ weights of all rats were examined. The liver weight in Groups 1, 2, 3, 4 was lower than that in Group 5, while that of the spleen in Groups 1 and 2 was higher than that in Group 5. 3) The Numbers of erythrocyte decreased in Groups 1 and 2 (p less than 0.01) and increased in Groups 3 and 4 (p less than 0.01) as compared with Group 5. There was no direct relation between the iron content in the diet and the number of leukocytes and their compositions. 4) Serum iron decreased remarkably in Groups 1 and 2 (p less than 0.01) but there were no intergroup differences in blood glucose value. 5) When osmotic fragility of erythrocyte membranes was expressed in term of NaCl concentration to indicate 50% hemolysis, Groups 1, 2 and 3 apparently increased their resistance as compared with Group 5 (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献