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H Ishikawa

Publications and source records attributed to H Ishikawa.

At least 73 records · Page 4Linked to original sources
PubMed2001

Expression of host S-adenosylmethionine decarboxylase gene and polyamine composition in aphid bacteriocytes.

Differential cDNA display and quantitative RT-PCR revealed that mRNA of host S-adenosylmethionine decarboxylase (SAMDC) was abundant only in the aphid endosymbiotic system well organized in young hosts, suggesting that SAMDC plays some important roles in the system. SAMDC is a key enzyme to synthesize polyamines that are known to be involved in a large array of biological events including protein synthesis, DNA stabilization, DNA replication, and cell proliferation. As the first step to investigate roles of polyamines in the endosymbiotic system, polyamine composition in bacteriocytes was determined by high performance liquid chromatography. As a result, we found that bacteriocytes contained virtually an only single polyamine, spermidine. The spermidine content of bacteriocytes fluctuated with time in the course of development and aging of the host aphid. This is the first report of polyamine assessment in a prokaryote-eukaryote endocellular symbiotic system, which demonstrated a unique polyamine composition.

Adenosylmethionine Decarboxylase↗
PubMed2001

Binding of CO at the Pro2 side is crucial for the activation of CO-sensing transcriptional activator CooA. (1)H NMR spectroscopic studies.

CooA is a heme-containing transcriptional activator that anaerobically binds to DNA at CO atmosphere. To obtain information on the conformational transition of CooA induced by CO binding to the heme, we assigned ring current-shifted (1)H NMR signals of CooA using two mutants whose axial ligands of the heme were replaced. In the absence of CO, the NMR spectral pattern of H77Y CooA, in which the axial histidine (His(77)) was replaced with tyrosine, was similar to that of wild-type CooA. In contrast, the spectra of CooADeltaN5, in which the NH(2) termini including the other axial ligand (Pro(2)) were deleted, were drastically modulated. We assigned three signals of wild-type CooA at -4.5, -3.6, and -2.8 ppm to delta(1)-, alpha-, and delta(2)-protons of Pro(2), respectively. The Pro(2) signals were undetectable in the upfield region of the spectrum of the CO-bound state, which confirms that CO displaces Pro(2). Interestingly, the Pro(2) signals were observed for CO-bound H77Y CooA, implying that CO binds to the trans position of Pro(2) in H77Y CooA. The abolished CO-dependent transcriptional activity of H77Y CooA is therefore the consequence of Pro(2) ligation. These observations are consistent with the view that the movement of the NH(2) terminus triggers the conformational transition to the DNA binding form.

Bacterial Proteins↗
PubMed2001

The effects of p53 status and human papillomavirus infection on the clinical outcome of patients with stage IIIB cervical carcinoma treated with radiation therapy alone.

BACKGROUND: It has been suggested that the p53 tumor suppressor gene regulates the radiosensitivity in human malignancies after irradiation; however, in cervical carcinoma, the role of the p53 gene is still unclear because of inactivation of functional p53 by infection with human papillomavirus (HPV). The objective of this study was to clarify the effects of p53 status and HPV infection on the clinical outcome of patients with cervical carcinoma after undergoing radiation therapy. METHODS: Fifty-two patients with International Federation of Gynecology and Obstetrics Stage IIIB squamous cell carcinoma of the cervix who received radiation therapy alone were reviewed. The combination of external beam irradiation therapy and three sessions of intracavity brachytherapy irradiation was performed for all patients. Genomic DNA extracted from paraffin embedded tissues was examined for HPV types 16, 18 and 33 by the polymerase chain reaction (PCR) method and for p53 status by PCR-single-strand conformation polymorphism (PCR-SSCP) technique. The effects of HPV infection, p53 status, and other parameters on clinical outcome were investigated by univariate analysis. RESULTS: HPV-DNA was detected in 40 patients (76.9%), and 14 patients (26.9%) had mutations of the p53 gene in the study. There was a significant correlation between the existence of HPV and p53 status (P < 0.001). Mutations of the p53 gene were detected in 6 of 12 patients (50%) who had local recurrent tumors, whereas p53 were wild type in 32 of 40 patients (80%) who achieved local control. The p53 mutation had a significant correlations with local tumor recurrence. Furthermore, p53 status caused statistical significant differences in the curves of the recurrence free survival rate and local control rate as determined by the log rank test (P = 0.02 and P = 0.03, respectively). Conversely, no obvious correlation with any clinical outcome for patients with cervical carcinoma was found concerning HPV infection. CONCLUSIONS: It is possible that the p53 gene may be used as a predictive factor in radiation therapy for patients with Stage IIIB squamous cell carcinoma of the cervix.

Adult↗
PubMed2001

An accessory role of TCRgammadelta (+) cells in the exacerbation of inflammatory bowel disease in TCRalpha mutant mice.

T cell receptor alpha mutant (TCRalpha (-/-)) mice, which spontaneously develop colitis under conventional conditions, did not show any signs of colitis under germ-free conditions, leaving TCRalpha (-)beta (+) cells (beta (dim) cells) and TCRgamma delta (+) cells much reduced. Moreover, TCRalpha (-/-) mice with alymphoplastic mutation (aly/aly TCRalpha (-/-) mice), which lack Peyer's patches and peripheral lymph nodes, did not suffer from colitis. While both beta (dim) cells and TCRgamma delta (+) cells were present in the colons of aly/aly TCRalpha (-/-) mice and aly/+ TCRalpha (-/-) mice, cytotoxicity of colonic TCRgamma delta (+) cells in aly/aly TCRalpha (-/-) mice was almost abolished. Transfer of TCRgamma delta (+) cells from TCRalpha (-/-) mice into scid/scid mice or aly/aly TCRalpha (-/-) mice could not induce colitis, but injection of anti-TCRdelta mAb into TCRalpha (-/-) mice prevented colitis from developing. Finally, TCRalpha (-/-) mice expressing transgenic (Tg) KN6-TCRgamma delta hardly developed colitis, accompanied by colonization of non-cytotoxic Tg TCRgamma delta (+) cells in their colonic mucosa. These results demonstrate that intestinal resident TCRgamma delta (+) cells may be involved in the exacerbation of inflammatory bowel disease in TCRalpha (-/-) mice.

Animals↗
PubMed2001

Abundance of unconventional CD8(+) natural killer T cells in the large intestine.

Natural killer T (NKT) cells are mainly present in the liver and thymus, and the majority of these T cells express either a CD4(+) or a double-negative (DN) CD4(-)8(-) phenotype. In the present study, we examined whether such NKT cells were present in the intestine. NKT cells were rare in all sites of the small intestine, including an intraepithelial site. However, a considerable number of NKT cells were found at an intraepithelial site in the large intestine. This result was confirmed by both immunofluorescence and immunohistochemistry. In contrast to conventional NKT cells, NKT cells in the large intestine were CD8(+) or DN CD4(-)8(-). In the case of conventional NKT cells, their existence is known to depend on non-classical MHC class I-like antigens (i. e. CD1d) but not on classical MHC class I antigens. However, the NKT cells in the large intestine were independent of the presence of both CD1d and classical MHC class I antigens. These results were obtained using knockout mice lacking the corresponding genes and molecules. NKT cells in the large intestine were mainly alpha betaTCR(+) (> 75 %) but did not use an invariant chain of Valpha14Jalpha281, which is preferentially used by conventional NKT cells. These NKT cells did not bias the TCR-Vbeta usage toward Vbeta8. These findings suggest that the large intestine is a site in which unconventional NKT cells carrying the CD8(+) phenotype (or DN CD4(-)8(-)) are abundant and that these cells are independent of MHC and MHC-like antigens.

Animals↗
PubMed2001

A comparison of ovarian metastasis between squamous cell carcinoma and adenocarcinoma of the uterine cervix.

OBJECTIVE: The purpose of our study was to investigate a possible difference in ovarian metastasis between squamous cell carcinoma and adenocarcinoma of the uterine cervix and to confirm clinicopathological variables associated with the metastases. METHODS: Clinical and pathological variables of 1064 patients with invasive squamous cell carcinoma and 240 with adenocarcinoma were studied. RESULTS: Ovarian metastasis was found in 14 patients (1.3%) with squamous cell carcinoma and 15 (6.3%) with adenocarcinoma. The mean age of patients with ovarian metastasis of squamous cell carcinoma was 57.4 years, compared to 50.2 years for adenocarcinoma. Ovarian metastasis of adenocarcinoma was more likely to be visible (40.0%) and present in both ovaries (66.7%), while these two characteristics occurred in only 21.4 and 36.7% of patients with squamous cell carcinoma. A logistic regression analysis with clinical variables indicated that clinical stage beyond IIb was a significant variable of squamous cell carcinoma, and more than 30-mm tumor size was significant in adenocarcinoma. CONCLUSION: The incidence of ovarian metastasis of adenocarcinoma of the uterine cervix was significantly higher than that of squamous cell carcinoma. The incidence of adenocarcinoma was associated more closely with tumor size than clinical stage, whereas it was more associated with clinical stage in squamous cell carcinoma. The results thus suggested that the differences in ovarian metastases were caused by the different characteristics of the two types of carcinoma.

Adenocarcinoma↗
PubMed2001

Combined grafting of thoracic aortic aneurysm and cardiac repair using continuous cold-blood coronary perfusion.

OBJECTIVE: For patients diagnosed with combined thoracic aortic aneurysms and cardiac lesions, we conduct a 1-stage operation for ascending and aortic arch grafting. We studied surgical outcome comparatively with patients undergoing aortic grafting alone. For descending and thoracoabdominal aortic grafting, we choose a 2-stage operation. SUBJECTS AND METHODS: Subjects were 80 patients undergoing ascending and aortic arch aneurysm repair between June 1994 and March 1999. Group 1 consisted of 30 undergoing simultaneous cardiac repair. Concomitant cardiac procedures involved 21 valvular, 5 coronary arterial, and 4 valvular and coronary arterial surgeries. Group 2 consisted of 50 undergoing aortic grafting alone. We used crystalloid cardioplegia and additional antegrade continuous cold-blood coronary perfusion in Group 1, and crystalloid cardioplegia alone in Group 2. RESULTS: Hospital mortality was 10% in Group 1 and 2% in Group 2. Surgery length, cardiopulmonary bypass time, and aortic cross-clamping time in Group 1 were significantly longer than Group 2. Myocardial ischemic time did not differ significantly. Postoperative ICU stay, mechanical ventilation time and catecholamine support time did not differ significantly. Actuarial survival was 66.9 +/- 13.1% at 52 months in Group 1 and 87.2 +/- 4.8% at 57 months in Group 2 (p = 0.2918). CONCLUSION: Simultaneous cardiac repair and ascending and aortic arch aneurysm repair were conducted using continuous cold-blood coronary perfusion. Hospital mortality and mid-term survival did not differ significantly between groups.

Aged↗
PubMed2001

5'-deoxy-5-fluorouridine, medroxyprogestrone acetate and mitoxantrone hydrochloride for advanced or recurrent breast cancer.

BACKGROUND: In treating advanced or recurrent breast cancer, anthracycline-containing chemotherapy is used for palliation and to maintain quality of life. However, there are several drawbacks including therapeutic failure and cardiotoxicity. We evaluated the efficacy and toxicity of combination chemotherapy with 5'-deoxy-5-fluorouridine (5'-DFUR), medroxyprogestrone acetate (MPA) and mitoxantrone hydrochloride (MIT). METHODS: Sixteen patients with advanced or recurrent breast cancer were enrolled. Chemotherapy was given in a 28-day cycle, starting with MIT 10 mg/m2 intravenously on day 1, then oral 5'-DFUR 800 mg and MPA 800 mg daily. Two or more cycles were given. RESULTS: Fifteen patients were assessable for response and toxicity. Thirteen patients had been treated previously with an anthracycline containing regimen and 2 with CMF. There were 2 partial response patients (13.3%) and 1 complete response patient (6.7%). There were 11 patients showing no change (NC) (73.3%), one of whom was a minor responder and 7 with a long period of NC. There was only one with progressive disease patient. The overall response rate was 20.0%. Adverse events occurred in 5 patients (33.3%). Myelosuppression was the most common with 5 patients becoming leukopenic (33.3%). Nausea/vomiting was the second most common side effect, affecting 2 patients (13.3%). CONCLUSION: Given its high efficacy and preservation of QOL, the combination of MIT, 5'-DFUR and MPA can be a 2nd or 3rd line therapy for advanced or recurrent breast cancer, especially for anthracycline-resistant cases.

Adult↗
PubMed2001

3-hour infusion of single-agent paclitaxel for recurrent ovarian cancer.

BACKGROUND: The clinical response, survival, and toxicity of a 3-h infusion of single-agent paclitaxel (175 mg/m2) for Japanese patients with recurrent ovarian cancer were investigated. We also examined whether or not cancer antigen (CA) 125 would be suitable as an indicator of the effects of the paclitaxel on ovarian cancer. METHODS: Twenty-one patients clinically diagnosed as having recurrent ovarian cancer met the entry criteria, agreed to participate in this study, and received the treatment. RESULTS: One hundred and twenty-six courses were administered to the 21 patients. One patient achieved a complete response, and 5 a partial response; the overall response rate was 35.3%. Using CA125 criteria, 42.1% of patients achieved a response. The median progression-free interval was 4.4 months, and the median overall survival time was 14.5 months. While hematological toxicity was not severe, 3 patients experienced severe peripheral neuropathy, and 2 patients experienced grade 4 myalgia/arthralgia. CONCLUSION: The 3-h infusion of single-agent paclitaxel (175 mg/m2) was an effective treatment for patients with recurrent ovarian cancer. CA125 was a useful indicator of the response to the treatment. While peripheral neuropathy and the myalgia/arthralgia were severe, 3-h infusion of single-agent paclitaxel offers a promising treatment for recurrent ovarian cancer.

Adult↗
PubMed2001

The platelet-sparing effect of paclitaxel is not related to changes in the pharmacokinetics of carboplatin.

PURPOSE: To determine whether the platelet-sparing effect of paclitaxel is related to changes in pharmacology of carboplatin. METHODS: A group of 32 patients with epithelial ovarian cancer were treated with intraperitoneal (i.p.) carboplatin-based chemotherapy with carboplatin alone or in combination with cyclophosphamide or paclitaxel, and the relationship between the pharmacology of serum platinum and thrombocytopenia was examined. The target AUC of i.p. carboplatin was 6.5 mg min/ml. Cyclophosphamide was administered intravenously at 400 mg/m2 after i.p. carboplatin and paclitaxel at 175 mg/m2 was given before i.p. carboplatin. RESULTS: Ten patients received i.p. carboplatin alone, 10 received cyclophosphamide and 12 received paclitaxel. The ages of the patients, body surface area, serum creatinine, platelet count before chemotherapy, and the total dose of carboplatin in each patient were similar in all groups. The measured AUC, Cmax, T 1/2, and MRT were similar in these groups. The nadir platelet counts were significantly higher (P = 0.0018) in patients treated with i.p. carboplatin with paclitaxel (12.1 +/- 4.3 x 10(4)/mm3) compared with carboplatin alone (5.2 +/- 3.3 x 10(4)/mm3) or with cyclophosphamide (5.2 +/- 4.8 x 10(4)/mm3). The percentage decrease in platelet counts was significantly lower (62.5 +/- 18.2%) in patients treated with paclitaxel than in the other two groups (81.5 +/- 12.6% carboplatin alone, 88.7 +/- 7.9% with cyclophosphamide). CONCLUSION: The addition of paclitaxel or cyclophosphamide to i.p. carboplatin did not alter the pharmacology of serum platinum. Thrombocytopenia was significantly less in patients treated with carboplatin in combination with paclitaxel. The platelet-sparing effect of paclitaxel is not related to changes in the pharmacology of carboplatin.

Age Factors↗
PubMed2001

Surgical treatment and subsequent outcome of patients with carcinoma of the splenic flexure.

Extended resection, comprising extended right hemicolectomy, splenectomy, and distal pancreatectomy, has been advocated for carcinoma of the splenic flexure because the lymphatic drainage at this site is variable. The present study addresses the problems associated with selecting the most appropriate operative procedure to achieve cure of splenic flexure cancers. We conducted a retrospective review of 27 patients with splenic flexure cancer who underwent curative resection. Left partial colectomy was performed in 20 patients and partial resection of the transverse/descending colon was performed in 7 patients. The combined resection of adjacent organs due to tumor adherence was performed in three patients. The spleen and distal pancreas were the organs most frequently resected among a collective total of six adjacent organs. The median duration of follow-up was 60.9 months after resection for splenic flexure cancer. No patient developed local recurrence. There was no significant difference in 5-year survival between patients with splenic flexure cancers and those with colon cancers at other sites. In conclusion, splenic flexure cancer resected by left partial colectomy or partial resection of the transverse/descending colon without routine extended resection was not associated with a worse prognosis than colon cancers at other sites.

Adenocarcinoma↗
PubMed2001

Flexible hinge toe implant arthroplasty for rheumatoid arthritis of the first metatarsophalangeal joint: long-term results.

We report the long-term clinical results and survival rate of the implant in flexible hinge toe implant arthroplasty of the first metatarsophalangeal joint, combined with a shortening oblique osteotomy of the metatarsal neck in the lateral toes, in patients with rheumatoid arthritis. Between 1983 and 1990, arthroplasty was performed on 97 feet in 66 patients. Twenty-seven patients died; follow-up information was available for 60 feet in the remaining 39 patients, who were followed for an average of 12 years. Twenty-nine patients (74%) were satisfied with the outcome after surgery, 7 were satisfied but had some pain or recurrent deformities, and 3 were unsatisfied. Radiologically, visible fracture was identified in nine implants. Four implants were removed because of infection (n = 2) or recurrent deformity (n = 2); no implant was removed because silicone synovitis developed. With revision as the endpoint, the implant survival rate was 93% at 10 years, and with radiographic implant fracture as the endpoint, the implant survival rate was 87% at 10 years. Shortening oblique osteotomy of the lateral toes appeared to decrease the rate of implant fracture and should be performed concomitantly with implantation when rheumatoid forefoot deformities are being reconstructed.

Adult↗
PubMed2001

Optimal doses of paclitaxel and carboplatin combination chemotherapy for ovarian cancer: a phase I modified continual reassessment method study.

BACKGROUND: A multicenter, phase I study of combination therapy with paclitaxel and carboplatin for epithelial ovarian cancer was conducted to determine the safety and recommended dosages for Japanese women. METHODS: Paclitaxel was administered intravenously over a 3-h period, followed by carboplatin administered intravenously over a 1.5-h period. A modified continual reassessment method (mCRM) was used in two treatment arms to establish the maximum tolerated dose (MTD) and recommended doses of the combination. In group A, the dose of paclitaxel (175 mg/m2) was constant and the dose of carboplatin was increased from 4 to 7 in terms of the target area under the plasma concentration-versus-time curve (AUC). In group B, the dose of carboplatin was constant (AUC 6) and paclitaxel was administered at two dose levels (160 and 175 mg/m2). In both groups, the carboplatin dose was limited to a maximum of 800 mg/body for each administration. RESULTS: Because the calculated probability of toxicity was greatest at a dose of paclitaxel 175 mg/m2 and carboplatin AUC 7, this dose was designated the MTD in group A. Based on this result, treatment in group B was initiated at doses of paclitaxel of 160 mg/m2 and carboplatin AUC 6. While the dose of paclitaxel was escalated to 175 mg/m2, the safety of the combination was confirmed. The most frequent adverse effect was neutropenia, which resolved promptly with the appropriate use of granulocyte-colony stimulating factor (G-CSF). No other severe hematologic or nonhematologic toxicities were observed. CONCLUSIONS: Our study demonstrated that the recommended dose for this combination regimen should be paclitaxel 175 mg/m2 plus carboplatin AUC 6 (maximum dose, 800 mg/body).

Adenocarcinoma, Clear Cell↗
PubMed2001

Ultrasound biomicroscopic diagnosis of cyclitic membranes.

PURPOSE: To evaluate the utility of ultrasound biomicroscopy in imaging cyclitic membranes. METHODS: Patients with hypotony and suspected or known cyclitic membrane underwent ultrasound biomicroscopic examination. Histopathology of cyclitic membrane was correlated with ultrasound biomicroscopy in three cases. RESULTS: Six eyes of six patients were enrolled. Mean patient age was 62.2 +/- 18.4 (SD) years. The mean intraocular pressure in the affected eye was 4.3 +/- 3.4 mmHg. Three eyes were pseudophakic and three eyes were aphakic. All eyes had undergone two or more previous intraocular surgeries. Ultrasound biomicroscopy imaged the cyclitic membrane in all six eyes. Histopathology revealed fibroproliferative cyclitic membranes with associated inflammatory cells. CONCLUSION: Ultrasound biomicroscopy is useful in detecting the presence of those cyclitic membranes that may not be identified on clinical examination.

Adult↗
PubMed2001

Glaucoma drainage tube kink after pars plana insertion.

PURPOSE: To describe focal obstruction of drainage tubes by kinking at the scleral entry site after pars plana insertion. METHODS: Case study. RESULTS: Three eyes of three patients underwent uncomplicated placement of a Baerveldt implant into the vitreous cavity at the time of pars plana vitrectomy. Intraocular pressure remained increased after the procedure without evidence of flow. Surgical exploration and modification of the tube placement resulted in immediate intraocular pressure reduction. Compression of the tube at the scleral entry site was confirmed intraoperatively in all eyes by ultrasound biomicroscopy. CONCLUSION: Kinking of the tube at its scleral entry site should be recognized as a possible cause of increased intraocular pressure without bleb formation after pars plana insertion of a glaucoma drainage implant.

Aqueous Humor↗
PubMed2001

Ultrasound biomicroscopy before and after goniosynechialysis.

PURPOSE: To report the ultrasound biomicroscopic appearance of the anterior chamber angle before and after successful goniosynechialysis. METHODS: Interventional case report. Ultrasound biomicroscopy using a 50-MHz transducer was performed in the supine position preoperatively and postoperatively in a 76-year-old woman with angle-closure glaucoma. RESULTS: Ultrasound biomicroscopy of the anterior chamber angle demonstrated restoration of an open anterior chamber angle after goniosynechialysis. CONCLUSION: High-resolution imaging of the anterior segment to evaluate preoperative and postoperative anatomy may be useful in eyes undergoing goniosynechialysis.

Aged↗