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Taro Yamamoto

Publications and source records attributed to Taro Yamamoto.

11 recordsLinked to original sources

Temperature-induced cell detachment on immobilized pluronic surface.

The Pluronic F68 and F127, a triblock copolymer of ethylene oxide and propylene oxide, was activated using carbonyldiimidazole (CDI), and CDI-activated Pluronic F68 and F127 was subsequently immobilized on the surface of a poly-L-lysine-coated polystyrene tissue culture flask. Cell culture was performed on the Pluronic-immobilized flask. The morphology of fibroblasts (L929 cells) on the Pluronic F127-immobilized flask was mainly spherical, and showed less spreading behavior than that on the Pluronic F68-immobilized flask and conventional tissue culture flask. This observation indicates that L929 cells on Pluronic F127-immobilized flasks were cultured in a bio-inert environment. L929 cells were successively detached from both Pluronic F127-immobilized flask and Pluronic F68-immobilized flask by cooling the flask to 4-15 degrees C. This detachment is due to the hydration and dehydration properties of Pluronic, depending on the temperature. Umbilical cord blood was cultured in the Pluronic F127-immobilized and conventional polystyrene tissue culture flasks at 37 degrees C. The expression ratio of surface markers on hematopoietic stem cells (CD34 and CD133) cultured in the Pluronic F127-immobilized flask was significantly higher than that of the cells in polystyrene tissue culture flask.

AC133 Antigen↗

Knowledge, attitude and practice towards HIV/AIDS in a rural Kenyan community.

The aim of this research was to explore people's knowledge, attitude, behaviour and practice towards HIV/AIDS and sexual activity in rural Kenya, where HIV is widespread. The study community was located in south-eastern Kenya, 50 km north of Mombassa, and had an estimated population of 1500. Subjects aged between 16 and 49 were recruited using a stratified cluster-sampling method and they completed self-administered questionnaires. Almost all respondents knew the word 'IV' Around 50% knew of a person living with HIV. About 80% gave 'death' or 'fear' as words representing their image of AIDS. With regard to sexual activity, the distribution of answers to the question 'how many partners have you ever had in your life' was bimodal in males but had only one peak in females, indicating that some men have a large number of sexual partners in their lifetime. First sexual intercourse was at around 12-13 years for both sexes, but female teenagers were more sexually experienced than their male counterparts.

Adolescent↗

Bioinert surface of pluronic-immobilized flask for preservation of hematopoietic stem cells.

The bioinert materials on which cells do not proliferate, differentiate, nor de-differentiate should be useful for the culture and preservation of stem cells. The Pluronic F127, a triblock copolymer of ethylene oxide, and propylene oxide was activated using carbonyldiimidazole (CDI), and CDI-activated Pluronic was subsequently immobilized on the surface of a lysine-coated polystyrene tissue culture flask. The morphology of fibroblasts (L929 cells) on the Pluronic-immobilized flask was spherical, and did not show spreading behavior. This observation indicates that L929 cells on the Pluronic-immobilized flask were cultured in a bioinert environment. The expression ratio of surface markers on hematopoietic stem cells (CD34 and CD133) cultured in the Pluronic-immobilized flask was significantly higher than that in polystyrene tissue culture flask and commercially available bioinert flask (i.e., low cell binding cultureware). This is caused by the existence of hydrophilic segments of Pluronic F127 on the Pluronic-immobilized flask.

Animals↗

Effects of a school-based education program for schistosomiasis control.

The role and effect of school-based education for schistosomiasis control needs to be explored further to raise the standard of health in the widely infected areas over the world. This study investigated the effect, particularly the retention or duration of effect, of a school education program for schistosomiasis control. The study was conducted from September 2000 to February 2001 in a district of Mount Darwin, Zimbabwe. Two hundred ninety-nine fifth graders from 8 primary schools were examined for their knowledge, attitude, beliefs and practice regarding schistosomiasis, based on a KABP form, three times in succession. The examinations were a baseline examination, a pre-examination checking for the effect of the program, and a post-examination assessing retention after three-months. Analyses of the examination results indicated a considerable effect of the program in all aspects except for practice. Further detailed analyses on 161 matched pair subjects comparing the difference between the pre- and post-examination results demonstrated how the subjects maintained or rather increased what they had learned, illustrating an amplifying resonance or percussion effect, that is, a group dynamic effect in the school setting. No clear correlation, however, was shown between the education effect and the infection rate of the subject groups. Ways to prevent the deterioration of the practice aspect, and the cause of the negative correlation between the infection rate and education effect need to be closely investigated, while trying out more participatory-type education is an absolute necessity.

Adolescent↗

Combating HIV/AIDS in Mainland China: an epidemiological review of prevention and control measures.

Two decades have already passed since the first HIV/AIDS case was described in 1981. Cumulatively, over 20 million people have unfortunately lost their lives, and more than 40 million people are now living with HIV, and most of them are from developing countries. China, as the biggest developing country, has an impact on the epidemic of HIV/AIDS. From the first case of AIDS diagnosed in Mainland China in 1985, the epidemic has spread at an alarming rate. The feature of HIV/AIDS spread in Mainland China concerns its geographical characteristics that can be described as occurring in three phases. According to data from World Health Organization (WHO), it was estimated that about 840,000 people are living with HIV/AIDS in China, and 80,000 of them have already developed AIDS. WHO warned that, if there were no effective preventive measures adopted, that the number of HIV/AIDS infected cases would reach 10 million in China by 2010. In this study, we described the current situation of the epidemic of HIV/AIDS, as well as an historic review. The development of policy-making and the control measures are also highlighted. The experience from China described in this study would hopefully be for more public awareness of this crisis that is threatening all the citizenry of China.

Acquired Immunodeficiency Syndrome↗

Effects of a low dose of indapamide, a diuretic, given daily or every-other-day on blood pressure and metabolic parameters.

To investigate the effects of the diuretic, indapamide, on blood pressure (BP) and metabolic parameters, thirty hypertensive patients were treated with 1 mg of indapamide either every day or every other day. BP, fasting plasma glucose, lipids, serum potassium and uric acid were determined at baseline and after 3 months of a stable regimen of the drug. At the termination of the study, 48-h ambulatory blood pressure monitoring (ABPM) was performed. Three patients received only indapamide, while other patients were treated in combination with additional antihypertensive medications. Patients treated with daily indapamide showed a BP reduction from 162 +/- 2.9/85 +/- 2.4 mmHg to 134 +/- 2.4/71 +/-2.6 mmHg (p < 0.001). The BP reduction was similar in those patients receiving the drug every other day (137 +/- 3.4/71 +/- 3.6 mmHg). While plasma lipids and serum potassium did not differ significantly with the intervention, uric acid increased significantly with daily treatment and normalized with every-other-day treatment. Glycosylated hemoglobin A1c (HbA1c) was not altered (5.6 +/- 0.1% vs. 5.4 +/- 0.2%), and did not differ between patients with and without diabetes mellitus. ABPM revealed an average 24-h BP of 134 +/- 3.3/75 +/- 1.7 mmHg on days in which patients received the medication and 139 +/- 4.9/78 +/- 2.6 mmHg on the intervening day without indapamide (no significant difference). These results suggest that a low dose of indapamide given every day or every other day is effective in lowering BP and does not result in metabolic derangements.

Aged↗

Effect of cilnidipine on insulin sensitivity in patients with essential hypertension.

To clarify the effect of cilnidipine, a long-acting dihydropyridine Ca-antagonist that blocks both L- and N-type Ca(2+)-channels, on insulin sensitivity, cilnidipine at 5 to 10 mg/day was administered to ten patients with essential hypertension for 12 weeks. Mean age and body mass index (BMI) were 57.7 +/- 5.0 (SEM) years old and 27.1 +/- 1.5, respectively. Blood pressure, serum levels of catecholamines, glucose and lipid were determined before and after the treatment. Insulin sensitivity was also measured by a euglycemic hyperinsulinemic clamp method using an artificial pancreas (STG-22; Nikiso, Tokyo, Japan) before and after the treatment. Cilnidipine administration significantly lowered blood pressure from 154/96 to 137/84 mmHg (p<0.05). The glucose infusion rate was significantly increased by 20.8%, from 3.27 +/- 0.36 to 3.95 +/- 0.55 mg/kg/min (p<0.05). HbA1C and serum lipid levels such as total cholesterol and triglyceride were not altered. In addition, cilnidipine treatment did not significantly increase serum norepinephrine levels (278 +/- 25.2 vs. 332 +/- 33.6 pg/ml). Our results suggest that cilnidipine improves insulin sensitivity, possibly due to its exerting a vasodilatory action without stimulating sympathetic nervous activity.

Blood Glucose↗

HIV/AIDS surveillance in Japan, 1984-2000.

The HIV/AIDS surveillance system in Japan, which began collecting data on the number of AIDS patients in 1984 and the number of HIV-infected persons in 1987, has played an important role in monitoring the trend and magnitude of Japan's HIV/AIDS epidemic and its distribution across various population subgroups. However, the system lacks any personal identifiers, making it impossible to eliminate duplication or to track cases for disease progression. It also does not permit the identification of the residence of HIV-infected persons because the residence of only the reporting physician is documented under the New Infectious Diseases Control Law, effective since April 1, 1999. The number of people with HIV/AIDS in Japan continues to grow. Among youth, sexually transmitted diseases, induced abortion, and sexual activities have shown a marked increase since the mid-1990s. Behavioral risk of infection for both injection drug users (IDUs) and men who have sex with men (MSM) remains alarmingly high. Accurate monitoring of infection rates is critical to the planning and evaluation of treatment, care and prevention programs. Japan should restructure its HIV/AIDS surveillance system to more accurately monitor the HIV/AIDS epidemic and related risk behaviors.

Female↗

Association of galectin-9 with eosinophil apoptosis.

BACKGROUND: There is no information whether galectin-9 (a novel eosinophil chemoattractant) was associated with pathogenesis of eosinophilic disorders. METHODS: We assessed the expression of galectin-9 with imunostaining and in situ hybridization both in the lesion of angiolymphoid hyperplasia with eosinophilia, and peripheral blood eosinophils of eosinophilic patients (E-Eos) in comparison with those of normal volunteers (N-Eos). Regulation of expression of galectin-9 on eosinophils and the effect of galectin-9 on apoptosis of eosinophil were also evaluated. RESULTS: Many eosinophils infiltrating the site were positive for galectin-9. Surface and intracellular immunoreactive galectin-9 was more evident in E-Eos than N-Eos. When eosinophils were cultured with IL-5 in vitro, the surface galectin-9 expression of E-Eos was significantly downregulated, although that of N-Eos was not affected. Treatment of eosinophils with dexamethasone or anti-Fas antibody significantly upregulated the surface galectin-9 expression of E-Eos. In contrast, dexamethasone partially downregulated the surface galectin-9 of N-Eos, although anti-Fas antibody failed to affect on the surface galectin-9 expression. We also found that recombinant galectin-9 significantly suppressed apoptosis of E-Eos (p = 0.0431), whereas it apparently enhanced apoptosis of N-Eos (p = 0.0173). Furthermore, dexamethasone-induced apoptosis of N-Eos was significantly suppressed by galectin-9 (p = 0.0431), whereas galectin-9 failed to induce significant change in dexamethasone-induced apoptosis of E-Eos. In contrast, apoptosis induced by anti-Fas antibody in both N-Eos (p = 0.0431) and E-Eos (p = 0.0431) was enhanced by galectin-9. CONCLUSIONS: These findings suggested that galectin-9 was produced by eosinophils, and galectin-9 showed heterogeneous effects and kinetics to eosinophils, and this factor might be one of crucial factors in eosinophilic inflammation.

Angiolymphoid Hyperplasia with Eosinophilia↗

Temperature-dependent cell detachment on Pluronic gels.

Cell culture on gels made of poly(ethylene oxide) and poly(propylene oxide) (Pluronic), which has a lower critical solution temperature around 30 degrees C, could be performed for 48 h. However, the Pluronic gels were highly hydrophilic and tended to dissolve in the culture medium. We achieved temperature-dependent detachment of cells from Pluronic gels containing or lacking extracellular matrix (ECM) by cooling the gels to 4 degrees C. Using normal human umbilical vein endothelial cells (HUVECs) grown on and released from Pluronic gels lacking ECM, we further found that the expression ratio of the surface markers CD34 and CD105 was twofold higher than for cells grown on polystyrene and removed with trypsin. In addition, the expression ratios for CD34 and CD105 on HUVECs cultivated on the Pluronic gels containing higher concentrations of ECM were lower, which may be due to ECM coating of the cell surface and, thus, interference with antibody binding. In summary, temperature-dependent detachment of cells from Pluronic gels allows the isolation of cells under mild conditions. This can be a powerful tool for surface marker analysis by flow cytometry.

Antigens, CD↗