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T Hoshi

Publications and source records attributed to T Hoshi.

At least 91 records · Page 5Linked to original sources
PubMed1995

Regulation of voltage dependence of the KAT1 channel by intracellular factors.

The KAT1 channel is a hyperpolarization-activated K+ channel cloned from the higher plant Arabidopsis. The deduced amino acid sequence suggests that its structural organization is similar to that of the Shaker-like K+ channel activated by depolarization. Electrophysiological properties of the KAT1 channel expressed in Xenopus oocytes indicate that voltage-dependent activation of the KAT1 channel is not caused by the divalent ion block and that it is intrinsic to the channel. Activity of the KAT1 channel progressively decreases upon patch excision. This rundown of the channel is accompanied by a large shift in the voltage dependence of the channel to a more negative direction. The voltage dependence is also regulated by pH, ATP, and cGMP.

Adenosine Triphosphate↗
PubMed1995

[Prevalence of urinary incontinence among institutionalized persons aged 60 and over in Japan].

In order to estimate the prevalence of persons experiencing urinary incontinence among the institutionalized aged 60 and over in Japan, a questionnaire survey was conducted in 16 prefectures in February 1991. The questionnaires were distributed and collected by the nurses in hospitals and in other facilities. A total of 10,022 residents were asked to answer a questionnaire on their urinary incontinence condition and 9,798 responses were analysed. The main results were as follows; 1) The prevalence rate of urinary incontinence occurring almost daily in hospitalized persons aged 60 and over was 23.3% for men, 23.8% for women. 2) The prevalence rate of urinary incontinence occurring almost daily in institutionalized persons aged 60 and over in special nursing homes was 64.2% of the aged 60 and over for men, 67.9% for women. 3) The prevalence of urinary incontinence increased with age for both sexes especially in hospitalized persons. 4) The 95% confidence interval estimate for the number of the hospitalized over 60 years old suffering from almost daily urinary incontinent incidents was estimated to be from 31,000 to 113,000 in men and from 60,000 to 182,000 in women. 5) The 95% confidence interval estimate for the number of the institutionalized in special nursing home over 60 years old suffering from almost daily urinary incontinent incidents was estimated to be from 34,000 to 50,000 in men and from 97,000 to 119,000 in women. 6) The 95% confidence interval estimate for the number of the institutionalized over 60 years old suffering from almost daily urinary incontinent incidents was estimated to be from 318,800 to 570,600 in both sexes. 7) A random sampling survey is required to elucidate the actual state of prevalence in all generations. 8) Future research should emphasize the assessment of preventive and medical interventions, as incontinence is preventable and medical and surgical treatment options are available.

Age Factors↗
PubMed1995

[Personnel requirements for health examination for 6 month and 9 mont-old children in municipalities in Japan].

Based on the Maternal and Child Health Law, municipalities offer health education, health counseling, health examination, and home visitation service for children and their mothers. In order to determine the personnel staffing requirements for the health examinations of 6 and 9 month-old children conducted independently by municipalities in Japan in 1989, data from the questionnaire survey executed by the Ministry of Health and Welfare in 1990 was analyzed. Questionnaires were sent to all municipalities and there were 3,198 responses for a response rate of 97.9% Results showed that in 1989, 27.5% of the 3,198 municipalities were able to perform health examinations for 6 month-old children and 24.7% for 9 month-old children. In the case of those cities which had populations over 10,000 but under 20,000, about 30% were able to perform the health examinations for 6 and 9 month-old children independently. In those cities which had health Centers, the health personnel system most adequately supported these health examinations. Due to the lack of health personnel, rural towns and villages with small populations required public health nurses to be assisted by other staff, most often public health nurses from prefectural Health Centers. For example, in those areas with populations less than 3,000, about 42-45% of the total volume of the work required to be performed by public health nurses during the health examinations for 6 and 9 month-old children had to be covered by assistance from prefectural public health nurses.

Child Welfare↗
PubMed1995

[Health personnel staffing requirements for health examination for the age of 1 1/2 in municipalities in Japan].

Municipalities in Japan offer health education, health counseling, health examination, and home visit services for each development stage of children and for their mothers. In order to determine personnel staffing requirements for the health examination for the age of 1 1/2 as of 1989, data from a questionnaire survey in 1990 conducted by the Ministry of Health and Welfare, was analyzed. Questionnaires were sent to all municipalities and there were 3,198 responses for the response rate of 97.9%. Results showed that in 1989, 98.9% of the 3,012 municipalities were able to independently perform health examinations for 1 and half year old, and in only 0.9% these examination were performed by clinical hospitals. In the large cities designated by the Government, the health personnel system adequately supported these health examination. However due to lack of health personnel, rural towns and villages with small populations required public health nurses to be assisted by other staff, such as health workers or volunteers. And particularly they required help by public health nurses from prefectural Health Centers. For example, in those areas with populations less than 3,000, 53% of the total volume of the work required to be performed by public health nurses during the health examination had to be covered by assistance from prefectural public health nurses. While in cities with more than 300,000 population large numbers of health personnel were assigned to examinations of children, the large number of children processed resulted in inadequate time for each child/mother pair. Further study of quality levels of the examinations need to be performed.

Child Health Services↗
PubMed1995

[The structural analysis of inpatient medical cost of the aged in 81 secondary medical areas of 12 Prefectures in Japan].

In order to understand the structure of the per capita medical care expenditure of inpatients aged 70 years and over, correlational and principal component analyses were performed using several medical cost indices for fiscal 1991 in 81 secondary medical areas of 12 prefectures. Requests were sent to all of 777 municipalities in the 12 prefectures, and there were 763 responses for the response rate of 98.2%. A total of 1,647,187 residents who had been inpatients based on receipts for inpatient medical care expenditure were surveyed. There were 389,456 who responded that they had been inpatients at least once in the preceding 12 months, in 1991. The main results were as follows: 1) Of the residents aged 70 and over, 32.0% of men and 29.7% of women surveyed had at least one episode of hospital admission in the preceding 12 months in 1991. 2) Large differences in the medical care expenditure per inpatient per year for those aged 70 years and over exist in the secondary medical areas in 12 prefectures. 3) In both sexes, per capita expenditures for inpatient care per year are positively correlated with the bed-days in hospitals per inpatient per year, the bed days per receipt, the medical care expenditure per receipt, and the number of receipts per inpatient per year. On the other hand, for women it is negatively correlated with per capita medical care expenditure per day, but it is not statistically significant. 4) The medical care expenditure per inpatient per day is significantly negatively correlated with bed-days in hospital per receipt, the number of receipts per inpatient per year, bed-days in hospital per inpatient per year for both sexes. On the other hand, it is significantly positively correlated with medical care expenditure per receipt for both sexes.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

[Educational needs of home health care nurses].

Because of the rapid growth and changes occurring in home health care, nurses have a need for acquiring additional education and nursing skills. Post-RN (registered nurse) education in home health care, however, has not been developed yet. The purpose of this study was to identify the significant educational needs of the home health care nurses in order to upgrade nursing skills. A survey was conducted of members of the nursing society for intractable-diseases and other home health nurses introduced by some of the members. The survey questionnaires were sent to 172 subjects and the response rate was 79.6%. Practical nurses and inactive nurses were excluded to leave 125 registered nurses who were subjects of this analysis. The major findings in this study were as follows: a) The mean age of the respondents was 42.1 years old. The average length of clinical nursing experience was 17.0 years. b) Among fifty home care nursing skills indicated higher implementation percentage than high-technology nursing skills. c) The personal care skills as well as high-technology nursing skills showed low difficulty, while interviewing and counseling skill and communication skill showed high difficulty. d) The respondents showed high educational needs for mastering high-technology nursing, communication and counseling skills. e) Clinical nursing experience of hospital service was found to be significantly useful means for the respondents to perform most of the home care nursing skills. Reference books were utilized as supplementary to the clinical experience. f) When asked about their desire for educational resources to provide high quality home health care nursing, approximately 80% responded that they wanted to obtain up-to-date information, and opportunities for clinical practice training courses. On the basis of our findings, the following skills could be crucial for the home health nurses and should be included in continuing educational programs; interviewing and counseling, interpersonal communication, high-technology home health care nursing, and independent decision-making.

Adult↗
PubMed1995

[Usefulness of myocardial T2-weighted MR imaging using the turbo spin echo technique].

Myocardial T2-weighted imaging using the turbo spin echo technique was superior to the conventional spin echo technique because of the shorter scan time and reduced artifacts. Furthermore, single cardiac phase images of all planes could be taken within a short scan time. T2-weighted imaging using the turbo spin echo technique was an effective method to evaluate myocardial abnormalities.

Humans↗
PubMed1994

K-ras codon 12 mutations in biliary tract tumors detected by polymerase chain reaction denaturing gradient gel electrophoresis.

BACKGROUND: Although the prevalence of K-ras codon 12 mutations in biliary tract (BT) tumors has been addressed in previous studies, the results have shown large discrepancies in mutation frequency. METHODS: K-ras codon 12 mutations were investigated by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE), a sensitive method for detecting DNA base changes, in a large series of BT tumors. RESULTS: In A-549 cells, which are known to contain a G to A change at the first base of K-ras codon 12, the mutation could be detected by DGGE even after 1:16 dilution with normal DNA. Tumor samples were microdissected from paraffin embedded tissue sections to ensure the presence of the tumor cells. K-ras mutations were detected in 13 of 23 bile duct tumors (56.5%) and in 9 of 23 gallbladder tumors (39.1%) by DGGE. However, no mutations were detected in normal, hyperplastic, and dysplastic BT epithelium or in tumorlike lesions, such as adenomyomatous hyperplasia, cholesterol polyps, and cystitis glandularis proliferans. The samples exhibiting abnormalities on DGGE showed a base change at K-ras codon 12 when examined by oligonucleotide hybridization. CONCLUSIONS: K-ras codon 12 mutations are seen often in BT tumors, and a combination of microdissection and PCR-DGGE is an effective approach for their detection.

Adult↗
PubMed1994

Frequent K-ras mutations and absence of p53 mutations in mucin-producing tumors of the pancreas.

Mucin-producing tumors of the pancreas (MPT) are characterized by the production of much mucin and a benign course after surgical treatment. We examined 16 cases of MPT and 20 cases of "common" pancreatic duct cell carcinomas (DCC) in regard to K-ras and p53 mutations. The mutations were detected by constant denaturant gel electrophoresis in combination with other techniques using PCR products amplified from the samples microdissected from the tissue sections. K-ras codon 12 mutations were identified in all MPT and in 95% of DCC. On the other hand, p53 mutations were found in four of 20 (20%) DCC, and p53 was immunocytochemically overexpressed in 3 of the 4 mutated cases. However, no p53 mutations and no p53 overexpression were identified in the 16 MPT. These results indicate that, although the K-ras codon 12 mutations may be almost essential for the development of both MPT and DCC, p53 mutations seemed to be involved mainly to the latters.

Adenocarcinoma, Mucinous↗
PubMed1994

Shaker potassium channel gating. I: Transitions near the open state.

Kinetics of single voltage-dependent Shaker potassium channels expressed in Xenopus oocytes were studied in the absence of fast N-type inactivation. Comparison of the single-channel first latency distribution and the time course of the ensemble average current showed that the activation time course and its voltage dependence are largely determined by the transitions before first opening. The open dwell time data are consistent with a single kinetically distinguishable open state. Once the channel opens, it can enter at least two closed states which are not traversed frequently during the activation process. The rate constants for the transitions among these closed states and the open state are nearly voltage-independent at depolarized voltages (> -30 mV). During the deactivation process at more negative voltages, the channel can close directly to a closed state in the activation pathway in a voltage-dependent fashion.

Animals↗
PubMed1994

Shaker potassium channel gating. II: Transitions in the activation pathway.

Voltage-dependent gating behavior of Shaker potassium channels without N-type inactivation (ShB delta 6-46) expressed in Xenopus oocytes was studied. The voltage dependence of the steady-state open probability indicated that the activation process involves the movement of the equivalent of 12-16 electronic charges across the membrane. The sigmoidal kinetics of the activation process, which is maintained at depolarized voltages up to at least +100 mV indicate the presence of at least five sequential conformational changes before opening. The voltage dependence of the gating charge movement suggested that each elementary transition involves 3.5 electronic charges. The voltage dependence of the forward opening rate, as estimated by the single-channel first latency distribution, the final phase of the macroscopic ionic current activation, the ionic current reactivation and the ON gating current time course, showed movement of the equivalent of 0.3 to 0.5 electronic charges were associated with a large number of the activation transitions. The equivalent charge movement of 1.1 electronic charges was associated with the closing conformational change. The results were generally consistent with models involving a number of independent and identical transitions with a major exception that the first closing transition is slower than expected as indicated by tail current and OFF gating charge measurements.

Animals↗
PubMed1994

Shaker potassium channel gating. III: Evaluation of kinetic models for activation.

Predictions of different classes of gating models involving identical conformational changes in each of four subunits were compared to the gating behavior of Shaker potassium channels without N-type inactivation. Each model was tested to see if it could simulate the voltage dependence of the steady state open probability, and the kinetics of the single-channel currents, macroscopic ionic currents and macroscopic gating currents using a single set of parameters. Activation schemes based upon four identical single-step activation processes were found to be incompatible with the experimental results, as were those involving a concerted, opening transition. A model where the opening of the channel requires two conformational changes in each of the four subunits can adequately account for the steady state and kinetic behavior of the channel. In this model, the gating in each subunit is independent except for a stabilization of the open state when all four subunits are activated, and an unstable closed conformation that the channel enters after opening. A small amount of negative cooperativity between the subunits must be added to account quantitatively for the dependence of the activation time course on holding voltage.

Animals↗
PubMed1994

[Personnel requirements for health examination of infants under 5 months in municipalities in Japan].

Municipalities offer health education, health counseling, health examinations, and home visitation service for infants and their mothers. In order to determine what the personnel staffing requirements were for health examination of infants under 5 months for municipalities in Japan in 1989, a questionnaire survey was conducted in 1990. Questionnaires were sent to all municipalities and 3,198 responses were received for a response rate of 97.9%. Responses from 912 municipalities were considered invalid, leaving a total of 2,286 responses that were analysed. Results showed that 79.2% of the 2,286 municipalities were able to perform health examinations for infants under 5 months independently, while in 6.5% of the municipalities these examinations were performed by the clinical hospitals. Analysis by size of municipalities showed that 85.7% of the cities with populations of 500,000 or more were able to perform health examinations independently. In the large cities designated by the Government, the health personnel system adequately supported these health examinations. However in rural towns and villages with small populations, it was necessary for public health nurses to be assisted by other staff, most of whom were public health nurses from prefectural health centers. For example, in areas with populations of less than 3,000, about 60% of the total volume of the work required to be performed by public health nurses during the health examinations had to be covered by assistance from prefectural public health nurses.

Child Welfare↗
PubMed1994

[Differences in inpatient medical costs for the aged within one prefecture].

The rapid increase in the proportion of the elderly population has made the problem of medical costs increasingly important. This problem, however, is not uniform over all regions in Japan. In order to determine what factors are associated with per capita medical care expenditure of inpatients aged 70 years and over, in fiscal 1991, correlation analyses were performed using several indices of medical services, socioeconomic factors and medical supplies among 208 municipalities in one prefecture. Data from a survey in 1992 conducted by the Ministry of Health and Welfare was used in the analysis. Requests were sent to all 218 municipalities in one prefecture, and 208 responses were received a response rate of 95.4%. The main findings were as follows: 1) There were large differences in per capita medical care expenditure for those aged 70 years and over among the secondary medical areas in the prefecture. 2) Both the inpatient expenditures per person per year and bed-days in hospitals per person per year were positively correlated with number of hospital beds per 1,000, the aging population rate and death rate of those aged 70 years and over; but correlated negatively with the primary industry population rate for both sexes. 3) Inpatient expenditure per person per day was negatively correlated with the aging population rate, especially for men. 4) Three major factors that correlated significantly and positively with per capita medical care expenditure for those aged 70 years and over were bed days of inpatients per receipt, the total receipts per inpatient per year, and the number of the admission days of inpatients per year. These three major factors were negatively correlated but not significantly, with the per capita medical care expenditure per day. 5) Multiple regression analyses indicate that the aging population rate, the number of hospital beds per 1,000 of those aged 70 years and over, and death rate of those aged 70 years and over were independently correlated with the inpatient expenditure per person per year for both sexes. 6) Results of this analysis indicate that data from secondary medical regions within the prefecture rather than the municipalities yield a stronger possibility of clarifying those factors contributing to differences in per capita medical care expenditure.

Aged↗
PubMed1994

[Prevalence estimation of urinary incontinence among non-institutionalized persons aged 60 and over in Japan].

In order to estimate the total number and the prevalence rate of persons experiencing urinary incontinence among the non-instutionalized, aged 60 and over in Japan, a questionnaire survey was conducted in 16 prefectures in December 1991. The questionnaires were distributed and collected by public health nurses in Health Centers. A total of 12,180 questionnaires were administered. There were 11,528 responses (response rate of 94.6%), of which 11,142 were analysed. The main results were follows; 1) Daily urinary incontinence occurred in approximately 4.1% of the men and 5.3% of the women living at home. 2) 6.2% of the men and 8.9% of the women living at home had regular urinary incontinence with at least one episode of leakage per month in the preceding 12 months. 3) The prevalence of urinary incontinence increased with age for both sexes. 4) The 95% confidence interval estimate for the number of non-institutionalized persons over 60 years old suffering from urinary incontinent incidents nearly daily was estimated to be from 305,000 to 351,000 in men and from 554,000 to 675,000 in woman. 5) The 95% confidence interval estimate for the number of non-institutionalized persons over 60 years old with urinary incontinence of at least one episode of leakage per 5 months was from 3,507,000 to 3,889,000 for both sexes. 6) In order to determine age-specific prevalence for urinary incontinence for all age groups, a sampling survey is needed. 7) Research emphasizing the assessment of preventive interventions necessary since incontinence is preventable and medical and surgical treatment options are available.

Aged↗
PubMed1994

[Working hours of maternal and child health service personnel by type of occupation and municipality].

The working hours of maternal and child health service personnel were surveyed to describe the characteristics of maternal and child health activities by municipality in 1989. Questionnaires were sent to 24 health centers and the 122 municipalities they represent, and responses from 19 health centers and 103 municipalities were received. The results were as follows: 1) Of all health service personnel, the working hours for public health nurses per 100 births per year was the highest, followed by maternal and child health volunteers, office workers, nurses and physicians. 2) Total working hours increased with number of births per year. 3) No significant correlation was found in total working hours of personnel in health centers with those in the municipalities they represent. Total working hours of personnel of health centers and the municipalities they represent decreased as population size increased. 4) The number of types of occupation involved in maternal and child health service increased as the size of population of the municipality increased. 5) Of the total working hours for all types of occupations, the proportion of working hours for public health nurses averaged about 40% to 50%. 6) The proportion of working hours for infant health examinations increased with increasing population size of the municipality. However, the proportion of the hours for planning and evaluation decreased with increasing population size of the municipality. From this survey, it appears that maternal and child health activities by municipalities differed according to the population size of the municipality.

Child↗
PubMed1993

Transient increases of growth fraction during fractionated radiation therapy for cervical carcinoma. Ki-67 and PC10 immunostaining.

BACKGROUND: The Ki-67 and PC10 indexes are consistent with the growth and S-phase fractions, respectively. METHODS: Eighty-three biopsy specimens from 18 patients with cervical squamous cell carcinoma were examined before and during fractionated radiation therapy (RT), using an immunohistochemical method. RESULTS: The 18 patients were divided into two groups according to the Ki-67 index before RT; those with values of less than 42% (Group A; n = 11) and those with values of 42% or more (Group B; n = 7). The Ki-67 index in Group A increased approximately twofold at radiation doses of 5.4-9 Gy compared with values before RT. The Ki-67 index in Group B, which increased slightly at doses of 5.4-9 Gy, decreased by approximately one-fifth at a dose of 27 Gy, compared with the value before RT. The PC10 indexes in both groups showed little change to doses of 5.4-9 Gy. The mitotic indexes were less than 1% before RT and decreased to a minimum with doses of 18-27 Gy. There was no correlation between the Ki-67 and PC10 indexes before or during RT. CONCLUSION: In cancer tissues with a low growth fraction before RT, radiation doses of 5.4-9 Gy produced increases in the numbers of cycling cancer cells in the G1 or G2 phases. This transient increase possibly was attributable to the combined effects of the recruitment phenomenon and G1 or G2 block.

Adult↗