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Biomedical subjects

T Yamamura

Publications and source records attributed to T Yamamura.

At least 55 records · Page 3Linked to original sources
PubMed2000

Feasibility of a novel weekday-on/weekend-off oral UFT schedule as postoperative adjuvant chemotherapy for colorectal cancer. UFT Compliance Study Group, Kanagawa, Japan.

PURPOSE: When oral anticancer agents are used for adjuvant chemotherapy of colorectal cancer, compliance and feasibility become issues because of the long treatment time. Appropriate studies of these issues are lacking. We investigated compliance and feasibility during a weekday-on/weekend-off schedule of oral UFT (uracil-tegafur) over a period of 1 year administered as adjuvant chemotherapy to patients with colorectal cancer. PATIENTS AND METHODS: A UFT dose of 600 mg/day was prescribed according to a weekday-on/weekend-off schedule to 87 patients after potentially curative resection. Compliance was investigated in three ways: physician interview, patient self-report, and chemical analysis of urine. The results were compared with the dose prescribed. Feasibility was evaluated on the basis of two indices: relative performance (RP), which was the ratio of the actual total dose taken to the total dose planned, and individual dose intensity (IDI), which was the ratio of the actual dose taken to the dose planned during a given period. RESULTS: The compliance assessed by physician interview and by patient self-report conformed well with the prescribed dose, the rate of agreement among the three compliance measures being more than 94%. Chemical analysis of urine in 38 of the patients revealed that they were actually taking the drug. The RP was 0.72, and the IDI was 0.8. CONCLUSION: From these results, the feasibility of the weekday-on/weekend-off schedule was judged to be good. It is suggested that the feasibility would be even better if the dose of UFT was set according to body surface area.

Administration, Oral↗
PubMed2000

The effectiveness of preoperative intraluminal brachytherapy in preventing wall penetration and nodal involvement of rectal carcinomas.

A retrospective review was conducted of 115 patients with middle or lower rectal carcinoma, without distant metastasis, who were consecutively treated with preoperative intraluminal brachytherapy and radical surgery (IBT group). Another 115 rectal carcinoma patients treated with surgery alone were reviewed as a control (NIBT group). We investigated whether conventional pathologic stagings were correlated with prognosis. All tumors were diagnosed by the TNM classification. According to the distribution of pathologic staging in the resected specimens, the prevalence of totally ablated tumors (stage T0) in the IBT group was significantly higher than that in the NIBT group, but there were no significant differences in the distribution of other T stages between the two groups. Good local control was achieved for the stage-T3 tumors in the IBT group, similarly to the T < or = 2 tumors in both groups. In the IBT group, the survival period of the patients with stage-T4 tumors even after radiotherapy was significantly shorter than that of those with T3 tumors (P = 0.042), while those with N < or = 2-stage tumors had significantly longer survival periods than those with N3-stage tumors (P = 0.047). These findings demonstrate the usefulness of analyzing clinicopathologic parameters to predict local control and the prolongation of survival. Determining these factors will also help to identify high-risk patients likely to require more effective adjuvant chemotherapy.

Adult↗
PubMed2000

Fate of fibrin sealant in pericardial space.

BACKGROUND: Although fibrin sealant (Beriplast, Aventis Behring, Marburg, Germany) has been widely used as a supplementary measure for hemostasis during cardiac surgery in Europe and is becoming popular in the United States, the pharmocokinetics of fibrin sealant applied in pericardial space has not been elucidated. METHODS: A small incision was made on the epicardial surface of the left ventricle of a rat, and the incision was sutured. Total 0.2 ml of fibrin sealant containing iodine 125 (125I)-labeled fibrinogen, aprotinin, blood coagulation factor XIII and thrombin was applied to the area around the suture line. RESULTS: Distributions of 125I-labeled fibrinogen in the heart on postoperative days 1, 3, 7, and 14 were 48.2% +/- 1.8%, 20.7% +/- 2.2%, 0.15% +/- 0.02%, and 0.01% +/- 0.02%, respectively. The radioactivity was negligible in the blood, liver, spleen, and kidney except for the thyroid in which the radioactivity increased to 7.9% +/- 0.7% and 4.3% +/- 0.4%, respectively, on postoperative days 7 and 14. Iodine 125-labeled fibrinogen concentrations of the heart and other organs showed a similar change in the time course of distribution. Dense and thick fibrin network, observed on postoperative day 1, had dissipated and was thinner with collagen formation by postoperative day 7. CONCLUSIONS: Fibrin sealant applied to the pericardial cavity regresses rapidly and plays an important role in wound healing.

Animals↗
PubMed2000

Hyperapobetalipoproteinemia with compositional abnormality of LDL and IDL, a characteristic lipoprotein alteration in essential hypertension.

The number and composition of apoprotein B (apoB)-containing lipoproteins that are very low density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and low-density lipoprotein (LDL) have been analyzed in subjects with essential hypertension who have no obesity and glucose intolerance. Twenty-three essential hypertensive subjects without diabetes mellitus and obesity were recruited. VLDL, IDL, LDL, and high-density lipoprotein (HDL) were separated by ultracentrifugation in the 23 hypertensive and 17 healthy subjects (control group). ApoB was determined by highly sensitive latex agglutination method in each lipoprotein fraction. There were no significant differences in age and body mass index between the hypertension and control groups. In hypertension, cholesterol levels significantly increased in plasma (13%, P < .05) and in LDL (20%, P < .05), but decreased in HDL (-14%, P < .05). Triglyceride significantly increased in plasma (66%, P < .05) and in VLDL (105%, P < .05). ApoB also significantly increased in plasma and all lipoprotein fractions except HDL. (plasma, 35%; VLDL, 94%; IDL, 82%; LDL, 42%; P < .05). With respect to lipoprotein composition, the ratio of cholesterol to apoB significantly decreased in IDL (P < .05) and LDL (P < .05). In essential hypertension, the number of apoB-containing lipoproteins (VLDL, IDL, LDL) all increased. A low ratio of cholesterol to apoB without changes in the ratio of triglyceride to apoB was noted in IDL and LDL, indicating the presence of small dense lipoprotein particles. Characteristic disorders of pure essential hypertension are characterized by hyperapobetalipoproteinemia and small dense LDL.

Biomarkers↗
PubMed2000

Diagnostic value of ultrasound-guided fine-needle aspiration biopsy, core-needle biopsy, and evaluation of combined use in the diagnosis of breast lesions.

BACKGROUND: To investigate whether ultrasound-guided core-needle biopsy (US-CNB) has more diagnostic value for breast tumors than ultrasound-guided fine-needle aspiration biopsy (US-FNAB) and to evaluate their combined use in patients with breast tumors. STUDY DESIGN: US-FNAB was carried out in 233 patients with breast tumors (254 lesions); both US-FNAB and US-CNB (combined biopsy) were performed in 81 of these patients (82 lesions). The diagnosis obtained by US-FNAB and US-CNB was compared with the surgical findings and the diagnostic value of US-CNB and combined biopsy were retrospectively evaluated. RESULTS: The sensitivity of US-FNAB was 86.9%, the specificity was 78.6%, and the accuracy was 84%. In contrast, the sensitivity of US-CNB was 86.2%, the specificity was 95.8%, and the accuracy was 89%. The specificity of US-CNB was significantly higher than that of US-FNAB and the inadequate biopsy rate of US-CNB was significantly lower than that of US-FNAB. For combined biopsy, the sensitivity, specificity, and accuracy were all 100%. The sensitivity, specificity, and accuracy of combined biopsy were significantly higher than those of US-FNAB. CONCLUSIONS: These findings suggest that US-CNB is more useful than US-FNAB, and that a combination of US-CNB and US-FNAB can markedly improve the preoperative diagnosis of breast cancer.

Adult↗
PubMed2000

Insulin-like growth factor-I improves recovery of cardiac performance during reperfusion in isolated rat heart by a wortmannin-sensitive mechanism.

Insulin-like growth factor-I (IGF-I) has been shown to produce a short-term positive inotropic effect (PIE) in the myocardium under nonischemic conditions. IGF-I also conferred cytoprotection against ischemia and reperfusion injury in various organs. IGF-I may, therefore, facilitate the recovery of postischemic cardiac function. Isolated and crystalloid-perfused rat heart was subjected to 25 min of normothermic ischemia followed by 30 min of reperfusion. IGF-I produced PIE in a dose-dependent manner at concentrations ranging between 1 and 100 nM under nonischemic conditions. Although 1 nM isoproterenol produced much greater PIE and myocardial energy conversion efficiency (MECE) than did 65 nM IGF-I in this condition, the same concentration of IGF-I administered during reperfusion conferred better recovery of left ventricular function and MECE compared with isoproterenol. The improved cardiac performance by IGF-I was associated with lower release of creatine kinase (CK). Wortmannin (100 nM), a specific inhibitor of phosphatidylinositol kinase (PI-3 kinase), abrogated IGF-I-induced improvement of contractile function and inhibition of CK release in the postischemic heart. We conclude that IGF-I administered during reperfusion accelerates recovery of cardiac performance and mitigates myocardial injury through a wortmannin-sensitive mechanism.

Androstadienes↗
PubMed2000

Evaluation of J-pouch reconstruction after total gastrectomy: rho-double tract vs. J-pouch double tract.

OBJECTIVE: Various enteric reservoirs have been advocated to improve the quality of life after total gastrectomy. We evaluated the advantages of pouch reconstruction compared with traditional rho-double tract reconstruction. DESIGN: Prospective randomized study. SETTING: Second Department of Surgery, Hyogo College of Medicine, Japan. SUBJECTS: Forty patients who underwent total gastrectomy for cancer of the stomach were studied. INTERVENTION: Forty patients were randomly divided into two groups: 20 patients received rho-double tract reconstruction (RDT group), and 20 underwent J-pouch double tract reconstruction (PDT group) group. MAIN OUTCOME MEASURES: We compared the body weight, serum nutritional parameters, reflux score, scintigraphic esophageal reflux, food intake, and emptying time of the J-pouch or rho-limb between the two groups. RESULTS: No difference was noted between the two groups with regard to body weight, but food intake tended to be higher in the PDT group than in the RDT group. Total protein and albumin levels were higher in the PDT group than in the RDT group, while scintigraphic reflux was significantly less prominent in the PDT group. CONCLUSIONS: J-pouch reconstruction was superior with respect to protein metabolism, food intake and reduction of reflux esophagitis compared with the traditional RDT method. However, use of pouch reconstruction did not improve postoperative weight gain.

Female↗
PubMed2000

Long-term results of stapled and hand-sewn anastomoses in patients with Crohn's disease.

AIM: This study aimed at determining the reoperation rates of patients with anastomoses for Crohn's disease. The outcome of patients undergoing stapled anastomoses was compared with that of patients having hand-sewn anastomoses. METHODS: Sixty-three patients undergoing intestinal resection for Crohn's disease at our institution from 1987 to 1996 were studied in a prospective, randomized trial. The group undergoing stapling comprised 30 patients and 37 anastomoses. The group with a hand-sewn anastomosis comprised 33 patients and 45 anastomoses. The median follow-up period was 87 (range 36-140) months. RESULTS: There were no significant differences in operative indications or patients' age and sex between the groups. There was a significant difference in cumulative recurrences between the groups (Cox-Mantel test: p = 0.022). CONCLUSION: A stapled anastomosis after resection for Crohn's disease may delay reoperation in patients with symptomatic recurrence.

Adolescent↗
PubMed2000

Hla-DR2-restricted responses to proteolipid protein 95-116 peptide cause autoimmune encephalitis in transgenic mice.

In multiple sclerosis (MS) patients who carry the Class II major histocompatibility (MHC) type HLA-DR2, T cells specific for amino acids 95-116 in the proteolipid protein (PLP) are activated and clonally expanded. However, it remains unclear whether these autoreactive T cells play a pathogenic role or, rather, protect against the central nervous system (CNS) damage. We have addressed this issue, using mice transgenic for the human MHC class II region carrying the HLA-DR2 (DRB1* 1502) haplotype. After stimulating cultured lymph node cells repeatedly with PLP95-116, we generated 2 HLA-DR2-restricted, PLP95-116-specific T-cell lines (TCLs) from the transgenic mice immunized with this portion of PLP. The TCLs were CD4+ and produced T-helper 1 (Th1) cytokines in response to the peptide. These TCLs were adoptively transferred into RAG-2/2 mice expressing HLA-DR2 (DRG1* 1502) molecules. Mice receiving 1 of the TCLs developed a neurological disorder manifested ataxic movement without apparent paresis on day 3, 4, or 5 after cell transfer. Histological examination revealed inflammatory foci primarily restricted to the cerebrum and cerebellum, in association with scattered demyelinating lesions in the deep cerebral cortex. These results support a pathogenic role for PLP95-116-specific T cells in HLA-DR2+ MS patients, and shed light on the possible correlation between autoimmune target epitope and disease phenotype in human CNS autoimmune diseases.

Amino Acid Sequence↗
PubMed2000

Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 9). Testicular toxicity in male rats given adriamycin for two or four weeks.

The present study was performed to determine whether testicular toxicity can be detected of the administration of adriamycin (ADR), an anticancer drug, for 2 weeks. ADR was intravenously administered to Slc:SD male rats at 1 mg/kg once a week for 4 or 2 weeks, and 2 mg/kg once a week for 2 weeks. Suppression of body weight gain was observed in the 1 mg/kg/week (4 w) and 2 mg/kg/week (2 w) groups. The testes weights in these groups were also lower than those of the control group. On histological examination, a decrease in spermatogonia was observed in the 1 mg/kg/week (4 w) and 2 mg/kg/week (2 w) groups. No abnormalities were detected in the control and 1 mg/kg/week (2 w) groups. Stage analysis of seminiferous tubules was performed for control and 1 mg/kg/week (2 w) groups. In the 1 mg/kg/week (2 w) group, the numbers of spermatogonia in stages II-III, V and XII-XIII were significantly decreased. The numbers of preleptotene spermatocytes in stage VII and zygotene spermatocytes in XII-XIII were also significantly reduced in the same group. These findings suggest that the testicular toxicity of ADR can be detected after 2 weeks administration at a sufficient high dosage, if simplified morphometrical analysis is used.

Animals↗
PubMed2000

[A case of pulmonary actinomycosis radiologically mimicking a lung cancer].

A 59-year-old male clerk consulted in general practitioner due to cough and hemoptysis. A mass shadow was pointed out in the left upper lung field on a chest radiograph. Patient was referred to our hospital for further treatment. Any definitive daiagnosis could not be made after examinations including sputum culture, cytology and TBLB. Because a lung cancer was strongly suspected, an exploratory thoracotomy was performed. Actinomyces was detected by pathological study of excised specimen, with no evidence of cancer. ABPC was administered for two months postoperatively. The patient is doing well without recurrence of actinomycosis 2.5 years after the surgery. Pulmonary actinomycosis presenting a mass shadow on a radiograph may mimick a pulmonary tumor, especially a lung cancer. Pulmonary actinomycosis should be considered in a differential diagnosis of pulmonary lesion thought to be malignant.

Actinomycosis↗
PubMed2000

[Continuous hepatic arterial infusion of 5-fluorouracil with leucovorin for unresectable liver metastases from colorectal cancer].

Twenty-three patients with liver metastases from colorectal cancer were treated by continuous hepatic arterial infusion chemotherapy with 5-FU and Leucovorin. The regimen was that 500 mg/body of 5-FU with 30 mg/body of Leucovorin was administered continuously for 5 days, followed by no medication for 16 days. The effect of this therapy was evaluated and the relationship between this therapy and the overexpression of vascular endothelial growth factor (VEGF) or microvessel density (MVD) was also studied. Complete response was obtained in 4 patients and partial response in 3 patients; the response rate was 32%. The response rate was 60% in patients who underwent more than 7 courses. The response rate was 44% in patients with positive VEGF and 33% in patients with negative VEGF. The response rate was 50% in patients with an MVD of more than 30 and 33% in patients with an MVD of less than 30. The 3-year survival rate for patients who underwent more than 7 courses was 37.5%. This therapy had to be abandoned in 6 patients due to occlusion of the catheter. Skillful maintenance of the catheter is necessary for a high response rate and satisfactory prognosis using this therapy.

Aged↗
PubMed2000

[Optimal dosage of UFT in a weekday-on/weekend-off schedule as a postoperative adjuvant chemotherapy for colorectal cancer].

In evaluations of adjuvant chemotherapy with oral anticancer agents, compliance in taking the drug as prescribed (compliance), adverse reactions, and feasibility are important factors in setting the dose. A weekday-on/weekend-off schedule, in which 600 mg/day of UFT was taken for 5 consecutive days and not taken on the following 2 days, was carried out as a postoperative adjuvant chemotherapy for one year in 87 patients with colorectal cancer who had undergone potentially curative resection. The prescribed dose and the dose of ingestion confirmed by physician interview were both highly consistent with the dose of ingestion according to the patients' self reports, with consistency rates of more than 94% for both. Relative performance (RP) yielded a value of 0.72, and individual dose intensity (IDI) yielded 0.8 on average. Female gender, low body weight, and low body surface area were factors that negatively affected feasibility. None of the adverse reactions was serious. Based on the feasibility and adverse reactions, the dosage of UFT should be set according to the body surface area at 375-425 mg/m2/day. When this schedule is used as one arm of a controlled study, it is suggested that the dose should be decided with 400 mg/m2 as a guideline.

Adult↗
PubMed1999

Low density lipoprotein (LDL) binding affinity for the LDL receptor in hyperlipoproteinemia.

We measured the binding affinity of low density lipoprotein (LDL) for the LDL receptor in patients with various types of hyperlipoproteinemia and investigated the effects of LDL lipid composition and particle size on receptor affinity. LDL (1.019 < d < 1.063) was isolated by sequential ultracentrifugation from the serum of normolipidemic controls and patients with hyperlipoproteinemia. Patients with type IIa hyperlipoproteinemia had LDL with a similar receptor affinity to that of normal LDL. However, patients with hypertriglyceridemia (type IIb and type IV hyperlipoproteinemia) had LDL with a low receptor affinity, and the degree of the reduction in affinity paralleled the severity of the hypertriglyceridemia. The LDL of hypertriglyceridemic patients was rich in protein and triglycerides, had a low content of cholesterol and phospholipids, and was smaller than normal, thus resembling the atherogenic lipoprotein known as small, dense LDL. These abnormalities were observed even in patients with mild hypertriglyceridemia regardless of their serum cholesterol levels. The degree of alteration in LDL lipid composition and particle size was strongly associated with the reduction of LDL receptor affinity. We also examined the effects of two lipid-lowering agents (bezafibrate and probucol) on the characteristics of LDL. LDL receptor affinity was only improved when the lipid composition and particle size were normalized by drug therapy. Although it has been reported that decreased cholesteryl ester transfer protein (CETP) activity results in the formation of small LDL, plasma CETP activity was normal in the hyperlipoproteinemic patients and the normalization of LDL characteristics by drug therapy was not accompanied by an increase of CETP activity. Our results suggested that an abnormal lipid composition and/or small particle size might cause a decrease in the receptor affinity of LDL. These structural and functional abnormalities were reversed by drug therapy, underlining the importance of treating hypertriglyceridemia for the prevention of atherosclerosis.

Adult↗
PubMed1999

Assessment by transesophageal echography of atherosclerosis of the descending thoracic aorta in patients with hypercholesterolemia.

This study assesses atheromatous lesions and aortic stiffness of the descending thoracic aorta (DTA) in patients with hyperlipidemia by transesophageal echography (TEE) and investigates the relations between atherosclerotic lesions and aging or serum cholesterol levels in these patients. Subjects included 16 patients with familial hypercholesterolemia (FH), 15 non-FH hyperlipidemic patients (non-FH), and 17 age-matched normal subjects. With use of TEE, the DTA was divided into 4 longitudinal portions of equal length, and the atheromatous lesions of each portion of DTA were scored according to their character and extension by biplane 2-dimensional TEE. The scores of atheromatous lesions from all 4 portions were added together to give the total atheromatous score. Then, after measuring the instantaneous dimensional changes of DTA in a cardiac cycle by M-mode TEE and blood pressure (BP) by a cuff method, we calculated the aortic stiffness parameter beta = ln(systolic BP/diastolic BP)/([Dmaximum - Dminimum]/Dminimum). The beta was significantly higher in FH and non-FH subjects than in normal subjects. In both FH and non-FH subjects, the total atheromatous score correlated with total serum cholesterol levels (r = 0.64 [p <0.01]; r = 0.58 [p <0.05], respectively). There were significant correlations between age and beta in all 3 groups (FH, r = 0.67 [p <0.005]; non-FH, r = 0.53 [p <0.05]; normal subjects, r = 0.49 [p <0.05]), and the slopes of the regression lines of FH and non-FH subjects were much steeper than those of normal subjects. The incidence of atherosis in the DTA was significantly higher in hyperlipidemic patients than in normal subjects, even among the younger members of the hyperlipidemic population with progressive aortic stiffness.

Age Factors↗
PubMed1999

Identification of autoimmune T cells among in vivo expanded CD25+ T cells in multiple sclerosis.

Although clonal expansion of autoimmune T cells has been reported in multiple sclerosis (MS), very limited information is available on specificities, clonal size, or activation state of the expanded clones. Here we address the issue of clonal expansion by using a novel technique demonstrating clonotypes defined by single-strand conformation polymorphism of TCR beta-chain cDNAs. Examination of activated T cells (CD3+CD25+) isolated from the peripheral blood of MS revealed limited numbers (20 approximately 82) of expanded clones defined by single-strand conformation polymorphism clonotype. To estimate the Ag specificities of dominant clonotypes in the activated T cells, these samples were examined in parallel with Th1 T cell clones specific for myelin basic protein or proteolipid protein (PLP) derived from the same patients. Analysis of two patients demonstrated that the dominant clonotypes would contain those specific for myelin basic protein or PLP. Although the majority of the clonotypes could be detected only transiently, a PLP95-116-specific clonotype was found to persist for over 1 yr. Thus, single-strand conformation polymorphism clonotype analysis allows us to monitor the kinetics of given T cell clones in vivo and could provide useful information for designing clonotype (Id)-specific manipulation of human diseases such as MS.

Adult↗