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I Uchiyama

Publications and source records attributed to I Uchiyama.

At least 37 records · Page 2Linked to original sources
PubMed1995

[Relationship between daily high temperature and mortality in Kyushu, Japan].

We analyzed the relationship between daily high temperature and mortality in Kyushu, Japan, 1972-1990. Mortality rate was obtained by dividing the number of deaths in a certain daily high temperature category by person-days in the same category. The results were as follows: (1) With daily high temperature on the x-axis and mortality rate on the y-axis, the relationship between the two variables appeared to be V-shaped. The minimum mortality rate was observed at the 28 degrees C-33 degrees C level. (2) Among all deaths at 33+ degrees C level, the proportion of deaths from "excessive heat" never exceeded 0.4%. This suggested that heat stroke is not a major contributor to the V-shape formation. (3) The V-shape was observed even in 1990, suggesting that the rapid spread of air conditioners did not alter the relationship between daily high temperature and mortality rate. (4) For the 0-4 years age group, mortality was not temperature dependent. However, the 5-14 years age group showed high mortality rates at 33+ degrees C. This may be attributed to outdoor activities during summer. After 30 years of age, the overall mortality rates rose with age, with greater increases at lower ambient temperature levels. As a result, the 65+ years age group had the greatest temperature dependence. (5) Deaths from respiratory diseases, circulatory diseases, and senility were highly temperature dependent, whereas death from cancer was not temperature dependent. Deaths from digestive diseases, infectious diseases, and accidents showed moderate temperature dependence.

Adolescent↗
PubMed1994

Gnome--an Internet-based sequence analysis tool.

Gnome (GenomeNet Open Mail-service Environment) is a sequence analysis tool that enables an end-user to make use of several Internet- (mainly e-mail) based services with an easy-to-use graphical user interface. Users can conduct homology and motif searches, and database-entry retrieval against the latest databases by emitting search requests to and receiving their results form a search-server by e-mail. The search results are viewed and managed efficiently with this system. The Macintosh and X (Motif) versions of the Gnome client and the UNIX version of the Gnome server are available to academic users free of charge.

Computer Communication Networks↗
PubMed1993

[Perception of foreign residents toward Japanese smoking habits].

A questionnaire written in English was developed for a survey of attitude of foreign residents toward smoking in Japan. The questionnaire was mailed to 69 foreign companies and 101 foreign language schools and also distributed to foreign residents on a US military base and at Christian churches. Responses from 342 persons (116 female, 221 male, and 5 sex undefined) contributed to this research. More than half (64%) of the respondents were from North America. When classified according to smoking habits, 72 persons were smokers (21%) and 78 were ex-smokers (23%). The subjects felt the biggest difference in smoking habits to be at "restaurants", and expressed that they would most like to see smoking prohibited at "restaurants". Almost all subjects (89%) thought that, compared to smoking habits in their own countries, Japanese were "markedly worse" or "worse". The main reasons why Japanese smoking habits were different from their countries were perceived to be "lack of education or knowledge" (31%) and "lack of legal restrictions" (28%). Half of the female subjects thought that the number of smokers in the next decade in Japan will be "markedly increased" or "increased". The subjects answered that education was the most effective means to prevent young people from smoking and also the best way to reduce smoking in society.

Adult↗
PubMed1992

Construction of a dictionary of sequence motifs that characterize groups of related proteins.

An automatic procedure is proposed to identify, from the protein sequence database, conserved amino acid patterns (or sequence motifs) that are exclusive to a group of functionally related proteins. This procedure is applied to the PIR database and a dictionary of sequence motifs that relate to specific superfamilies constructed. The motifs have a practical relevance in identifying the membership of specific superfamilies without the need to perform sequence database searches in 20% of newly determined sequences. The sequence motifs identified represent functionally important sites on protein molecules. When multiple blocks exist in a single motif they are often close together in the 3-D structure. Furthermore, occasionally these motif blocks were found to be split by introns when the correlation with exon structures was examined.

Amino Acid Sequence↗
PubMed1992

Differentiation of fear, anger, and joy.

The purpose of the present study was to identify the physiological characteristics corresponding to three affects (fear, anger, and joy), which were elicited through real situations in a laboratory. The subjects were asked to rate their psychological responses using the Affect Rating Scales for each affective situation. Physiological indices (diastolic and systolic blood pressures, heart rate, respiration rate and frequency of galvanic skin response) were measured. The subjects' affects can be characterized by two functions obtained through discriminant analysis. One discriminant function separated positive from negative affects; the other set apart anger from the remaining affects.

Adolescent↗
PubMed1992

Acute effects of ozone on EEG activity, sleep-wakefulness and heart rate in rats.

Effects of exposure to O3 on EEG activity, sleep-wakefulness and heart rate were examined using conscious rats which had been chronically implanted with electrodes for EEG, EMG and ECG recordings. Exposure to 0.5 ppm O3 for 6 hrs and 1.0 ppm O3 for 3 hrs suppressed amounts of wakefulness (W) and paradoxical sleep (PS) at the expense of an increase in slow-wave sleep (SWS), and lowered the amplitude of fast EEG waves and heart rate (HR). The lowered EEG amplitude and the suppressed PS recovered more rapidly during the post-exposure period than did the lowered HR. The ip administration of atropine sulfate blocked the suppressed W, the increased SWS and the lowered HR, while the lowered EEG amplitude and the suppressed PS were not blocked. These observations suggest that the O3-induced bradycardia results from enhanced activity of cardiac parasympathetic nerves and that the O3-induced changes in W and SWS result secondarily from some circulatory factor including the bradycardia.

Animals↗
PubMed1990

Ozone-induced bradycardia and arrhythmia and their relation to sleep-wakefulness in rats.

Rats were chronically implanted with electrodes for EEG, EMG and ECG recordings and exposed to 0.1 ppm, 0.2 ppm ozone (O3) or clean air as control for 5 consecutive days. Amounts of wakefulness (W), slow-wave sleep (SWS) and paradoxical sleep (PS) of the O3-exposed rats were not statistically different from respective control values. Compared with control rats, heart rates of the O3-exposed rats decreased and the number of bradyarrhythmic episodes increased with an increase in O3 levels. The O3-induced bradyarrhythmias occurred more prevalently in the order of W, SWS and PS state. Parasympathetic mechanisms were suggested on those cardiac abnormalities.

Animals↗
PubMed1989

Effects of short- and long-term exposure to ozone on heart rate and blood pressure of emphysematous rats.

Electrocardiogram and arterial blood pressure of elastase-treated emphysematous rats (E rats) and saline-treated control rats (S rats) were recorded continuously during exposure to either 1 ppm ozone (O3) for 3 hr or 0.5 ppm O3 for 6 hr. The heart rates (HRs) of both groups decreased to about 50 and 65% of the initial levels at the end of 1 ppm and 0.5 ppm O3 exposure, respectively. Mean arterial blood pressures (MAPs) also decreased to about 76 and 82%, respectively. There was no significant difference in these responses between E and S rats, although the levels of HRs and MAPs of the E rats were always a little lower than those of the S rats. Another group of E and S rats was continuously exposed to 0.2 ppm O3 for 4 weeks. The HRs of both E and S groups decreased to about 81 and 88% of the initial levels on the first day, respectively, although they recovered completely by the third day. No significant difference in the variation of HRs during exposure was noted between E and S rats. However, the HR responses of these rats to a challenge exposure of 0.8 ppm O3 for 1.5 hr appeared to be different. That is, S rats were more tolerant of the challenge exposure to O3 for 1.5 hr than the E rats.

Animals↗
PubMed1988

4-Hydroxyretinal, a new visual pigment chromophore found in the bioluminescent squid, Watasenia scintillans.

The bioluminescent squid, Watasenia scintillans has three visual pigments. The major pigment, based on retinal (lambda max 484 nm), is distributed over the whole retina. Another pigment based on 3-dehydroretinal (lambda max approximately 500 nm) and the third pigment (lambda max approximately 470 nm) are localized in the specific area of the ventral retina just receiving the downwelling light. Visual pigment was extracted and purified from the dissected retina. The chromophores were then extracted and analyzed with HPLC, NMR, infrared and mass spectroscopy, being compared with the synthetic 4-hydroxyretinal. A new retinal derivative, 11-cis-4-hydroxyretinal, is identified as the chromophore of the third visual pigment of the squid.

Animals↗
PubMed1988

Adaptation of a deep-sea cephalopod to the photic environment. Evidence for three visual pigments.

Watasenia scintillans, a bioluminescent deep-sea squid, has a specially developed eye with a large open pupil and three visual pigments. Photoreceptor cells (outer segment: 476 micron; inner segment: 99 micron) were long in the small area of the ventral retina receiving downwelling light, whereas they were short (outer segment: 207 micron; inner segment: 44 micron) in the other regions of the retina. The short photoreceptor cells contained the visual pigment with retinal (lambda max approximately 484 nm), probably for the purpose of adapting to their environmental light. The outer segment of the long photoreceptor cells consisted of two strata, a pinkish proximal area and a yellow distal area. The visual pigment with 3-dehydroretinal (lambda max approximately 500 nm) was located in the pinkish proximal area, giving high sensitivity at longer wavelengths. A newly found pigment (lambda max approximately 471 nm) was in the yellow distal area. The small area of the ventral retina containing two visual pigments is thought to have a high and broad spectral sensitivity, which is useful for distinguishing the bioluminescence of squids of the same species in their environmental downwelling light. These findings were obtained by partial bleaching of the extracted pigment from various areas of the retina and by high-performance liquid chromatographic analysis of the chromophore, complemented by microscopic observations.

Adaptation, Physiological↗
PubMed1987

Pulmonary response to exposure to ozone of emphysematous rats.

Rats were treated with a single intratracheal instillation of 6.5 units elastase or normal saline. Seven weeks after treatment, the animals were exposed for 24 hr to filtered air or 1 ppm O3, and their lung functions were measured. The exposure to O3 resulted in functional changes depending mainly on peripheral airway obstruction, and the direction and degree of those functional changes were in general similar between the saline- and elastase-treated animals. Another group of saline- or elastase-treated rats were exposed to 3 ppm O3 for 3 hr and the edematous response of their lungs was again similar. These results indicate that elastase-treated lungs responded to the exposure to O3 in a fashion similar to normal lungs in rats, but lung damage caused by the exposure to O3 superimposed over preexisting emphysematous damage, resulted in an additional lessening of the margin of pulmonary reserve capacity.

Animals↗
PubMed1987

An emphysema model in rats treated intratracheally with elastase.

Pulmonary functions, morphology, and morphometry were examined in rats at 3, 7, and 10 weeks after a single intratracheal administration of 6.5 units of porcine pancreatic elastase in order to obtain a model of pulmonary emphysema which would be suitable for studying the responses of emphysematous lungs to atmospheric pollutants. Functional residual capacity and residual volume of the elastase-treated rats increased at all the times studied, but their total lung capacity increased only at 7 and 10 weeks compared with those of the saline-treated control rats. The increase in static lung compliance and the decrease in peak flow and maximum flow at 50% of total lung capacity during forced expiration were also observed in all except the 3-week elastase animals. The elastase-treated lungs showed morphological changes characteristic of emphysematous lesions. The increase in mean linear intercept length and the decrease in total alveolar surface area were demonstrated by these elastase-treated lungs. Based on these results, we conclude that an adequate and suitable model of pulmonary emphysema could be obtained in rats 7-10 weeks after treatment with the present dose of elastase.

Animals↗
PubMed1986

Effects of acute exposure to ozone on heart rate and blood pressure of the conscious rat.

Electrocardiogram and arterial blood pressure in conscious and unrestrained rats of various ages were recorded during a 3-hr exposure to filtered air or 1 ppm ozone (O3). In general, heart rate and mean arterial blood pressure of rats significantly decreased during exposure to O3, whereas these functional parameters remained almost stable during exposure to filtered air. Heart rate usually reached a plateau during the exposure to O3. Additionally, PR interval and QRS complex significantly increased and premature atrial contraction and incomplete A-V block were frequently observed during the exposure to O3. These circulatory effects of O3 were more markedly manifested by rats 11 weeks old than either those 8 or 4 weeks old. On the other hand, no significant difference in the circulatory responses was observed between male and female rats. These circulatory effects of O3 may be significant from the viewpoint of health effects, although its mechanisms remain unsolved.

Age Factors↗
PubMed1984

Pulmonary functions of rats trained with mild exercise.

The purpose of the present study was to determine if lung function is modified by physical exercise in male and female rats. The animals were subjected to a running program for 5 weeks. At the termination of the program period, the running rats (R) had body weight smaller than the sedentary control rats (S). In male rats, the weights of lung, heart and adrenal glands, which were corrected with body weight, were larger in the R than in the S, and the absolute weight of adrenal glands also increased in the R. The rates of peak flow and maximum expiratory flow at 50% total lung capacity, which were corrected with either body weight, lung weight or total lung capacity, increased in the R. Because of no significant change in the flow resistance and compliance of the lungs, the increases in the rates of these expiratory flows might have been due to increased airway rigidity caused by some mechanisms relating to exercise stimuli. In female rats, on the other hand, the above changes in the R were little or less.

Animals↗
PubMed1983

Exercise test in variant form of angina pectoris. Comparison of the results with spontaneous attacks.

Exercise tests were performed in 14 patients with untreated variant angina with frequent spontaneous attacks and in 15 patients after treatment abolished the attacks. (1) Anginal attacks associated with ST elevation were induced by exercise in 79% of untreated patients. By contrast, ST elevation was not observed in treated patients and ST depression was induced in 53% of the cases. (2) Exercise-induced ST elevation in untreated patients was shown in the same leads as the spontaneous attacks. (3) Exercise-induced ST elevation appeared initially during the recovery phase after exercise in 36% of untreated patients. Exercise-induced ST depression appeared during or immediately after exercise. (4) The reproducibility of exercise-induced ST elevation was low with repeated tests at different stages, but exercise-induced ST depression was consistently observed. (5) The exercise-induced ST depression and lack of ST changes in treated patients were highly suggestive of the presence and absence of organic coronary artery disease, respectively. However, the exercise-induced ST elevation in untreated patients did not differentiate between the presence or absence of organic stenosis of the coronary arteries. The results of exercise tests vary with the stage of variant angina. It is suggested that a coronary arterial spasm is a trigger mechanism for exercise-induced angina in cases of variant angina with frequent spontaneous attacks.

Adult↗
PubMed1982

Pacing echocardiography: regional wall motion, left ventricular dimension and R wave amplitude in patients with angina pectoris.

In view of the fact that stable echocardiograms are easily obtained during atrial pacing, pacing echocardiography was performed to evaluate the usefulness for detecting regional wall motion abnormalities during pacing-induced ischemia and to investigate the relationship between changes in the R wave and left ventricular dimension. The patients were 12 cases of angina pectoris (10 of coronary artery disease; CAD, and 2 of coronary patent aortic valvular disease; AVD) and 6 control cases. Simultaneous recording of two-dimensional and M-mode echocardiograms and electrocardiograms was done before, during and after the atrial pacing at increasing heart rate until angina appeared or the heart rate of at least 140/min was reached. In 12 angina cases, angina and ST depression were induced in 10 and 11, respectively. Excursion of the interventricular septum (IVS) decreased during pacing-induced ischemia in 6 of 7 CAD cases, in which the left anterior descending coronary artery was significantly stenosed (more than 75%). Excursion of the left ventricular posterior wall (LVPW) decreased during pacing-induced ischemia in 4 of 7 CAD cases, in which the vessels giving rise to posterior descending coronary artery were significantly stenosed (more than 75%). In 2 AVD cases, excursion of both IVS and LVPW decreased during ischemia. Left ventricular end-diastolic dimension (LVEDD) increased in only 2 angina cases, although R wave amplitude increased in 6 angina cases.

Adult↗