Search PubMed⌕ Search

Biomedical subjects

K Murakawa

Publications and source records attributed to K Murakawa.

At least 37 records · Page 2Linked to original sources
PubMed1997

Improvement of erythrocyte deformability by cholesterol-lowering therapy with pravastatin in hypercholesterolemic patients.

Erythrocyte deformation is an important regulatory factor of the microcirculation. The present study was designed to examine whether erythrocyte deformability is altered in hypercholesterolemic patients and, if so, whether cholesterol-lowering therapy affects this parameter in these patients. The erythrocyte deformability of 37 hypercholesterolemic patients was evaluated before and after 1 year of therapy with pravastatin, an inhibitor of hepatic hydroxymethyl glutaryl coenzyme A reductase, under various shear stresses (4.7, 9.5, 23.6, 47.3, 118.1, and 236.2 dyne/cm2) using laser diffractometry. At study entry, erythrocyte deformability under 4.7 and 9.5 dyne/cm2 shear stress, which is actually observed in human vessels, was reduced compared with that in 20 age-matched normocholesterolemic subjects and was inversely correlated with serum cholesterol and low-density lipoprotein (LDL) cholesterol. Pravastatin therapy for 1 year, which reduced serum cholesterol from 288 +/- 28 to 223 +/- 20 mg/dL, significantly improved erythrocyte deformability by approximately 20%. There was a significant relation between the improvement of erythrocyte deformability and the reduction of serum cholesterol or LDL cholesterol. The results suggest that erythrocyte deformability is reduced in hypercholesterolemic patients, and that long-term cholesterol-lowering therapy can improve reduced erythrocyte deformability, which may contribute to the improvement of organ perfusion.

Adult↗
PubMed1997

[Antinociceptive activity of intracisternal clonidine in the mouse].

The antinociceptive activities of clonidine have been determined against three qualitatively different noxious stimuli in the mouse. The methods used to evaluate this activity were selected to include tests which employ different types of noxious stimuli, i.e. heat (hot plate), chemical (acetic acid-induced writhing) and mechanical (tail pinch). Test drug and control treatments were given by cisternal injection in a dose volume of 10 microliters.mouse-1. The results presented here show that clonidine has potent antinociceptive properties against several types of noxious stimuli. Clonidine produced steep dose-response lines in all tests. The response to the writhing assays were completely inhibited by 1.0 microgram.mouse-1 of clonidine. In contrast in both the hot plate and tail pinch assay, however, clonidine did not produce a consistent antinociceptive effect at a dose of 200 micrograms.mouse-1. Utilizing these three different types of assays, the rank order of antinociceptive potency for clonidine in different noxia was the writhing >> hot plate > tail pinch. It was concluded from these results that clonidine has potent antinociceptive properties against chemical visceral stimuli.

Adrenergic alpha-Agonists↗
PubMed1997

[Evaluation of the automatic quantification of left ventricular function using ECG gated 99mTc-MIBI myocardial SPECT].

We studied the accuracy of left ventricular (LV) volumes and ejection fraction (EF) derived from ECG gated 99mTc-sestamibi myocardial perfusion SPECT (G-SPECT) and the software for automatic data analysis (QGS program described by Germano G et al.). G-SPECT was performed in 29 patients with various cardiac diseases. LV end-diastolic and end-systolic volumes (LVEDV and LVESV), and LVEF determined by QGS program were compared to those by Simpson method in biplane left ventriculography (LVG). Interobserver reproducibility in measuring the G-SPECT parameters was excellent (LVEDV: r = 0.99, LVESV: r = 0.99, LVEF: r = 0.97). There was a good correlation between the values obtained from G-SPECT and LVG (LVEDV: r = 0.92, LVESV: r = 0.94, LVEF: r = 0.85), but G-SPECT tended to underestimate LVEDV and LVEF. In 17 patients with moderate to severe myocardial perfusion defects selected from the subjects, the correlation was maintained fairly high (LVEDV: r = 0.90, LVESV: r = 0.92, LVEF: r = 0.77). In conclusion, QGS program provides high accuracy and reproducibility in determining LV volumes and LVEF from G-SPECT.

Adult↗
PubMed1996

[University education in geriatrics. Present status and future plans of universities regarding the development of a program in geriatrics].

Because the number of people who reach an advanced age has been increasing at an unprecedented rate in Japan, geriatricians are expected to play a central role in health care for the elderly. However, only 16 out of 80 medical schools (20 percent) now have departments of geriatrics for undergraduate education. To develop undergraduate education in the field of geriatrics, a survey was sponsored by the Research Projects on Aging and Health (Health Science Research Grant the Ministry of Health and Welfare of Japan). A questionnaire regarding the present status and future plans of the university about a program in geriatrics, was sent to deans of medical faculties or vice-presidents of medical schools. The questionnaire included questions about current status and future plans regarding undergraduate geriatric education, the presence of a department or clinic of geriatrics, educational requirements in the field of geriatrics, opportunities for practice, institutions of practice, research on geriatrics, and other suggestions. The response rate was 93.7 percent (74/79). Departments or clinics of geriatrics had been established in 15 institutions (20.3 percent) and were planned in 18 (24.3 percent). Undergraduate education in geriatrics was considered necessary in 73 schools (98.7 percent) and indispensable as an obligatory subject in 56 (75.7 percent). Clinical practice was considered more important and effective than lectures in 50 schools (63.3 percent). Coordinated lectures on basic biomedical gerontology (such as mechanism of aging) and geriatric medicine for chronic degenerative diseases such as senile dementia were considered essential to the curriculum. In practicing geriatrics, experience in providing medical care to aged patients as well as social support and a welfare system for the aged is emphasized. Institutions, nursing homes, and geriatric hospitals outside medical schools be easily accessible. It was generally agreed that geriatrics should be taught in advanced classes. In conclusion, medical schools in Japan regard undergraduate education in geriatrics as necessary and agree on the optimal curriculum, but it is not universally implemented.

Education, Medical, Undergraduate↗
PubMed1996

[University education in geriatrics. Opinions of teaching staff on undergraduate education in gerontology and geriatric medicine].

Undergraduate education in gerontology and geriatric medicine has become more important because of a progressive increase in the aged population. To assess curricula in geriatric medicine and to survey the opinions of teaching staffs as to the ideal curriculum, a questionnaire was sent to professors of gerontology and geriatric medicine at 14 medical schools. Responses were obtained from all 14 professors. In all medical schools, students are given lectures in the fifth or sixth year, or both. The total number of hours for the lectures varied from a few hours to 40 hours, and contents of the lectures varied between schools. Medical staffs pointed out that little time is allocated to geriatric medicine. They also emphasized the importance of bedside teaching.

Curriculum↗
PubMed1996

[University education in geriatrics: medical student's opinions on gerontology and geriatric medicine].

With the aging of Japan's population, physicians need to be aware of advances in geriatric medicine. To assess the status of geriatric medicine in undergraduate education, we surveyed of medical student's opinions on gerontology and geriatric medicine. A questionnaire was sent to six-year medical students at a total of 20 schools that did not include geriatric medicine in their curriculum. Responses were obtained from 950 students (47.6%) at 16 schools (80%). Almost half of the students (42%) had experiences in health care facilities for the elderly. Ten percent were content with their education in geriatric medicine education and 59% were not. A total of 41.4% felt that geriatric medicine is difficult because it involves many different subjects. Some students had experience as volunteers working with elderly people; they were aware of the aging of Japan's population, and felt that their training in basic geriatrics and in geriatric diseases was insufficient. A total of 56% agreed that all medical schools should have classes in geriatric medicine and 14% did not. Medical students in the schools without classes in geriatric medicine identified dementia (73%), cerebral vascular accidents (51%), cancer (24%) and osteoporosis (19%) as common in elderly people, with no differences between schools. The corresponding data for medical students in schools with classes in geriatric medicine were dementia (77%), cerebral vascular accidents (44%), osteoporosis (29%), and cancer (16%). Undergraduate medical students seem to be exposed to widely differing curricula with regard to geriatric medicine. We found a lack of uniformity in the teaching of gerontology and geriatric medicine to undergraduate medical students in Japan.

Education, Medical, Undergraduate↗
PubMed1996

[Undergraduate teaching of geriatric medicine in western countries--literature review].

To help plan for the future of undergraduate education in geriatric medicine in Japan, we reviewed the literature concerning undergraduate teaching of geriatric medicine in western countries. Undergraduate teaching in geriatric medicine in the UK is well developed: 22 of 25 universities have a full department of geriatric medicine. Training in geriatric medicine is mandatory in almost all universities. In contrast, geriatric medicine is an elective in most universities in the US. There is a shortage of geriatric medicine faculty in the US, which is similar to the situation in Japan. Clinical and basic research in geriatric medicine and gerontology should be encouraged to attract persons into this field.

Education, Medical, Undergraduate↗
PubMed1996

[University education in geriatrics--present status and future prospects of gerontology and geriatrics education in pathology].

The increase in the number and proportion of the elderly in Japan over the last 30 years has been faster than that in any other country. One of the measures we are compelled to take to deal with this drastic change in medicosocial circumstances is reform of the medical school curriculum. However, the necessary reforms are being implemented slowly and are still insufficient. We surveyed the present status of gerontology and geriatrics education in pathology, and the understanding, interest, and opinions on this matter among professors of pathology. Questionnaires were sent to 148 professors of pathology in 80 medical schools. Responses were received from 84 professors (57%) at 64 medical schools (80%). Of the 11 medical schools with a department of geriatrics 10(90%) included gerontology in the curriculum. In contrast, 43(80%) of the 53 remaining schools did not include gerontology in the curriculum, although education in geriatrics and gerontology has been given as part of pathology lectures in almost all medical schools. Many professors want to establish a department of geriatrics in their school, but feel it will be difficult because of lack of money and higher priority given to other fields. As other hindrances, most of the respondents noted the lack of money and higher priority given to other fields. As other hindrances, most of the respondents noted the lack of a good textbook of gerontology, ambiguity in the concept of the field, and the immaturity of gerontology as a science. Another major problem noted was uncertainty regarding the status of geriatrics as a clinical specialty. One professor mentioned that promotion of aging research would be the best way to solve these problems.

Education, Medical, Undergraduate↗
PubMed1996

[Differentiation of antinociceptive effects of mu, delta and kappa agonists using heat, chemical and mechanical nociception].

The antinociceptive properties of mu (D-Ala2, N-Me-Phe4, Gly5-ol, enkephalin, DAGO), delta (D-Ala2, D-leu5, enkephalin, DADL) and kappa (dynorphin, DYN) were assessed using hot plate (heat), acetic acid-induced writhing (chemical) and tail pinch (mechanical) assays in mice. Test drug and control treatments were given by cisternal injection in a dose volume of 10 microliters.mouse-1. DAGO and DADL produced steep dose-response lines in all the tests. DYN did not produce a consistent antinociceptive effect on the tail pinch test. Utilizing these three different types of assays, the rank order of antinociceptive potency for these three opioids was DAGO > DADL > DYN. The responses to the hot plate and writhing assays were completely inhibited by the same dose of DAGO. DADL displayed equal antinociceptive effects in the hot plate and writhing tests. In the tail pinch assay, however, antinociceptive potency of DAGO was 1/3 less than in other two assays, and DADL was also 1/10 less than in the others. The rank order of antinociceptive potency for DYN in different noxia was the writhing > hot plate >> tail pinch. It was concluded that there are differences in the potency of mu-, delta- and kappa-agonists even when the intensities of chemical and heat noxia are equal. It was also proposed that antinociceptive potencies against mechanical noxia is greatly different among mu-, delta- and kappa-agonists.

Acetic Acid↗
PubMed1995

Development of the brainstem and cerebellum in autistic patients.

Studies of magnetic resonance images have revealed morphological disorders of the brainstem and cerebellum in autistic children and adults. When we studied development of the brainstem and cerebellum in autistic patients, we found that although the brainstem and cerebellum significantly increased in size with age in both autistic patients and controls, these structures were significantly smaller in autistic patients than in controls. The speed of development of the pons, the cerebellar vermis I-V and the cerebellar vermis VI-VII was significantly more rapid in autistic patients than in the controls. However, the speed of development of the other brain structures in the posterior fossa did not differ between autistic patients and controls. The regression intercepts of the brainstem and cerebellum as well as those of their components were significantly smaller in autistic patients than in controls. Results suggest that brainstem and vermian abnormalities in autism were due to an early insult and hypoplasia rather than to a progressive degenerative process.

Adolescent↗
PubMed1995

Effects of electrical stimulation of cervical sympathetic trunks on microcirculation in the facial nerve.

This study evaluates the circulatory effects of electrical stimulation of the cervical sympathetic trunks on blood flow in the common carotid artery and facial nerve tissue in dogs. Marked increases in arterial pressure and heart rate were observed due to electrical stimulation of the cervical sympathetic trunks, while blood flow volume in the common carotid artery and in the facial nerve tissue decreased markedly. It was assumed that microcirculation of the facial nerve is definitely impaired by electrical stimulation of the cervical sympathetic trunks, and the tonicity of the sympathetic nervous system appears to be a major factor in changes in the microcirculation of the facial nerve. It is well known that impaired circulation in the nutrient vessels of the facial nerve has an important effect on the pathogenesis of facial palsy. The hypertonicity of the sympathetic nervous system is closely involved in the onset of facial palsy.

Animals↗
PubMed1995

[Changes of tympanic temperature by stellate ganglion block].

The effects of stellate ganglion block (SGB) on the temperature of tympanic membrane were determined clinically. Thirty patients received SGB with 8 ml of 1 % mepivacaine. The tympanic temperature was measured using radiation non-contact tympanic membrane thermometer before and after administration of SGB for 30 min on the side where SGB was given. Before SGB the tympanic temperature was 37.29 +/- 0.08 degrees C, and there was no difference in the readings between the two sides. The tympanic temperature dropped significantly 5 min after SGB and reached its lowest value of 36.90 +/- 0.08 degrees C 15 min later. This drop persisted for more than 30 min after SGB. The fact that therapeutic effect of SGB is partly due to vasodilation and improvement in blood flow to the affected region was demonstrated, but these effects in internal carotid arterial system have not yet been studied in detail. Tympanic temperature has been proposed as a valid index of brain temperature in man. The mechanism of brain cooling has been suggested that countercurrent heat exchange takes place between carotid and jugular blood flow. Therefore the result of the study suggests that SGB could enhance an increase in the brain blood flow.

Adolescent↗
PubMed1994

Chromosomal assignments of 3'-directed partial cDNA sequences representing novel genes expressed in granulocytoid cells.

Large scale cDNA sequencing of 3'-directed cDNA libraries allows the collection of hundreds of novel sequences (gene signatures) and understanding of their expression levels in various tissues. Granulocytoid cells were induced from the human promyelocytic leukemia cell line 60 (HL60) with dimethyl sulfoxide (DMSO), and more than 1000 gene signatures were collected from a 3'-directed cDNA library of the granulocytoid cells. By selecting appropriate sequences for primer design, we systematically assigned chromosomes of these novel gene signatures by means of the polymerase chain reaction. We used a monochromosomal hybrid cell panel DNA as the template and localized 155 gene signatures to individual chromosomes. The results showed that 125 of them were assigned to single chromosomes and 30 to more than one. Genes assigned to more than one chromosome tend to be expressed ubiquitously, and their sequences are often conserved among humans and rodents. A highly sensitive laser fluorescent analyzer and ethidium staining were used for simple and large-scale PCR mapping.

Animals↗
PubMed1994

Chromosomal assignment of HepG2 3'-directed partial cDNA sequences by Southern blot hybridization using monochromosomal hybrid cell panels.

Large-scale sequencing of a 3'-directed cDNA library from the human liver cell line HepG2 has generated several hundred species of cDNA gene signatures, about 85% of which identify novel genes. They are useful molecular landmarks for human genome mapping. We used 160 of these novel signatures as probes for Southern hybridization to human DNA. We then identified the copy number of the corresponding genes and assigned them to chromosomes, with reference to monochromosomal hybrid cell mapping panels. The distribution profile of the expressing genes among chromosomes suggested that the expressing gene density is not uniform.

Animals↗
PubMed1994

The use of overlapping and tailed short primers in the chromosomal assignment of short cDNAs by the polymerase chain reaction.

For the PCR-based chromosomal assignment of very short cDNA fragments specifically designed primers are required. We tested primers with very short core sequences that are identical or complementary to known cDNA sequences, with or without tails at the 5' ends. The lower limit of the core length for PCR using human chromosome templates was 14 nucleotides (nt) when they have tails. The minimal length of the tail was 2 nt when it was attached to the 5' end of a 14-nt core. In the absence of a tail, 15 nt are needed for the core to act properly. The overall size of the short cDNA fragments that could be assigned was further reduced by using a pair of primers that overlap at the 3' ends. The limits of the free energy of overlap were about -1.9 kcal/mol at 45 degrees C, -2.9 kcal/mol at 50 degrees C and -4.5 kcal/mol at 55 degrees C. A combination of these features in a primer pair allowed cDNA fragments as short as 30 nt to be assigned.

Animals↗
PubMed1994

A human cDNA sequence homologue of bovine phosphatidylethanolamine-binding protein.

Sequencing of about 1000 3'-directed cDNA clones from the human HepG2 cell line revealed that about half of them represent transcripts of abundantly or moderately expressed genes, about 70% of which are novel. We identified one of these clones as encoding the human homologue of bovine phosphatidylethanolamine-binding protein.

Amino Acid Sequence↗