Biomedical subjects

M Abe

Publications and source records attributed to M Abe.

At least 775 records · Page 43Linked to original sources

PubMed1993

Atrial natriuretic peptide and left atrial systolic function in normal subjects.

The purpose of this study is to elucidate factors determining the release of atrial natriuretic peptide (ANP) in normal volunteers at rest. Ten normal volunteers were included in this study. Ages ranged between twenty-seven and thirty-three years (mean twenty-seven). The authors measured plasma levels of ANP, and four cardiac chamber volumes, and their functions by cine magnetic resonance imaging using the rephased gradient-echo method. Plasma levels of ANP in 10 normal subjects were 15.0-37.1 pg/mL (mean 23.6 pg/mL). No significant relationship was seen between ANP level and heart rate or blood pressure. The level of ANP was positively correlated with left atrial (LA) emptying fraction and negatively correlated with LA minimal volume (r = 0.85, P < 0.01; r = 0.64, P < 0.05, respectively). No significant relationship was observed between plasma ANP level and left ventricular, right ventricular, or right atrial parameters. These results suggest that LA systolic function is one of the major determinants for ANP release in normal subjects at rest.

Adult↗

PubMed1993

Precise assessment of myocardial damage associated with secondary cardiomyopathies by use of Gd-DTPA-enhanced magnetic resonance imaging.

To evaluate the myocardial damage in patients with secondary cardiomyopathies, the authors examined gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA)-enhanced magnetic resonance imaging (MRI) in 5 patients (2 with cardiac amyloidosis, 2 with acute myocarditis, 1 with cardiac thyrotoxicosis). MR images were performed at 1.5-T by using a spin echo pulse sequence before and after intravenous administration of Gd-DTPA (0.2 mmol/kg). All patients revealed distinct high-intensity areas on postcontrast images. Moreover, MRI with Gd-DTPA could determine the severity and precise regions of myocardial damage associated with secondary cardiomyopathies. It is suggested that gated cardiac MRI with Gd-DTPA enhancement is useful for detecting the myocardial damage in secondary cardiomyopathies.

Acute Disease↗

PubMed1993

Effects of glyceryl trinitrate on blood pressure and arterial compliance.

Glyceryl trinitrate (GTN) mainly reduces systolic blood pressure (SBP) rather than diastolic blood pressure (DBP) in acute conditions. To examine the efficacy of GTN as an antihypertensive agent in patients with isolated systolic hypertension (ISH), the authors examined the effects of GTN on BP and arterial compliance (AC) in patients who underwent cardiac catheterization. Seventy patients (with old myocardial infarction, 36; angina pectoris, 25; chest pain syndrome, 9) who underwent cardiac catheterization because of chest pain were included in this study. They were aged between thirty-seven and seventy-four (mean sixty-one) years. According to the levels of BP at cardiac catheterization, the authors selected two subgroups: the normotensive group (NT group, n = 18) and the isolated systolic hypertensive group (ISH group, n = 20) from all subjects. The authors measured BP before and after (three minutes) sublingual administration of GTN (0.3 mg) at the cardiac catheterization. AC was assessed by means of diastolic pressure decay. The change of BP was estimated by the differences between values before and at three minutes after GTN. After administration of GTN, SBP was decreased significantly from 157 +/- 25 to 142 +/- 23 mmHg (P < 0.01), while DBP did not change (83 +/- 13 vs 84 +/- 15 mmHg). The change in SBP was positively correlated with the pretreatment SBP and negatively correlated with AC (r = 0.51, P < 0.001; r = 0.39, P < 0.001, respectively). AC was significantly lower in the ISH group than in the NT group (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Cervico-pectoral ectopia cordis in two Holstein calves.

Two Holstein calves affected with cervico-pectoral ectopia cordis, a male (No. 1) delivered stillborn and a female (No. 2) died 1 hour after birth, were examined macroscopically and radiographically to assess the severity and elucidate the teratogenesis of the anomaly. The heart of one calf was covered by the intact pericardium and skin and displaced to the caudalmost portion of the ventrocervical region, just cranial to an enlarged thoracic inlet. The cranial vena cava and the vena azygos were duplicated. The sternum was bilaterally divided into two parts fused only at the xyphoid process and was semicircular. The heart of the other calf, covered solely by the pericardium, was exposed ventrally from an oval opening in the body wall just cranial to a defective Y-shaped sternum. In both calves, the arterial branching pattern from the aortic arch was intermediate between the patterns of the dog and pig, and in each case a single pulmonary vein emptied into the left atrium. Pronounced or slight torticollis, cleft palate, and abnormalities in the urogenital system were also found. From an embryological perspective, cervical and pectoral ectopia cordis have a common pathogenesis; the cervical type occurs at a slightly earlier fetal stage than the pectoral type.

Animals↗

PubMed1993

Werner's syndrome associated with spastic paraparesis and peripheral neuropathy.

A Werner's syndrome patient with spastic paraparesis and polyneuropathy had slowing of central and peripheral nerve conduction. Sural nerve biopsy revealed a significantly higher frequency of demyelination and remyelination and a loss of myelinated fibers. These data suggest that the central and peripheral nervous systems are affected in Werner's syndrome.

Adult↗

PubMed1993

Effect of regression of cardiac hypertrophy on ischemic myocardial damage in spontaneously hypertensive rats.

Effects of reduction of blood pressure and regression of left ventricular hypertrophy following hydralazine and captopril therapy on ischemic cardiac function and myocardial metabolism were studied in spontaneously hypertensive rats (SHR). Hydralazine (1.5 or 3 mg/kg/day) and captopril (50 or 100 mg/kg/day) were administered to SHR from 19 to 26 weeks of age. Both hydralazine and captopril significantly decreased arterial blood pressure in SHR, but only captopril significantly reduced left ventricular weight. The percentage of V3 myosin isozyme significantly decreased in captopril-treated SHR compared to hydralazine-treated SHR. At the end of long-term treatment, hearts were removed and perfused for 15 min by the working heart technique, and then global ischemia was induced for 30 min. The ischemic heart was reperfused for 30 min. In hydralazine-treated SHR and captopril-treated SHR, the pressure-rate product and extent of recovery of the coronary flow during reperfusion following 30 min of ischemia were higher than those in control SHR, but this difference was significant only in captopril-treated SHR. Hydralazine and captopril treatment improved the restoration of the levels of ATP, creatine phosphate, total adenine nucleotide and energy charge potential in SHR after reperfusion following 30 min of ischemia, but only captopril had a significant effect. In conclusion, regression of left ventricular hypertrophy is more important than lowering of blood pressure in order to improve the ischemic myocardial damage.

Animals↗

PubMed1993

The detection and modification of the hypoxic fraction in quiescent cell populations in murine solid tumours.

Mice bearing SCC VII or EMT6/KU tumours were irradiated after receiving 10 injections of 5-bromo-2'-deoxyuridine (BUdR) to label all proliferating tumour cells, and the tumours were then excised and trypsinized. The tumour cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BUdR labelling was determined using immunofluorescence staining to BUdR. This MN frequency was then used to calculate the surviving fraction of unlabelled cells from the regression line for the relation between MN frequency and the surviving fraction of all tumour cells. Thus a cell survival curve could be determined for cells not labelled by BUdR, which can be regarded as quiescent tumour cells for all practical purposes. Assays performed immediately after irradiation of both normally aerated and hypoxic tumours showed that quiescent cells contained higher hypoxic fractions than the tumour cells as a whole. Furthermore, administration of nicotinamide before irradiation or the placement of mice in a circulating carbogen (95% O2, 5% CO2) chamber for 30 min before and during irradiation altered the acutely and chronically hypoxic fractions of the proliferating and quiescent tumour cell populations in a way which depended on the tumour system. Combined nicotinamide and carbogen therapy was shown to have a large potential to sensitize cells to low-dose radiation in vivo. In addition, this assay method appears to be useful for determining the size of the hypoxic fraction of quiescent tumour cells in murine solid tumours.

Animals↗

PubMed1993

Electron microscopic studies on reticular fibers in the pig sheathed artery and splenic cords.

The reticular fibers of the capillary sheath and splenic cord were studied in the pig spleen by transmission electron microscopy to reveal their components and the presence of sialic acid in the amorphous ground substance. Collagen fibrils, elastic fibers, microfibrils, nerve fibers and smooth muscle cells were observed in the reticular fibers of the splenic cord, while only microfibrils were recognized in the reticular fibers of the capillary sheath. The binding of LFA lectin to the splenic cord was stronger than the capillary sheath. These findings may suggest that the reticular fibers of the splenic cord include numerous functional elements and perform an important role during contraction or dilation of the spleen. On the other hand, it seems to be reasonable to term the capillary sheath as "capillary basement membranous reticular tissue", since the reticular fiber of the capillary sheath resembles the basement membrane of the capillary in its components.

Animals↗

PubMed1993

Three-dimensional reconstruction of the pig sheathed artery.

The structure of the sheathed artery and the number of branches of the sheathed capillary were investigated by three-dimensional reconstruction computer graphics in the pig spleen. The capillary branched 1 to 6 times in the capillary sheath in more than 90% of all samples examined. The sheathed artery varied in shape and size in accordance with the number of branches and direction of the capillary. The usual descriptions for the sheathed artery were suggested to be mostly in appropriate at least for that of the pig spleen.

Animals↗

PubMed1993

Effects of captopril or nitrendipine on left ventricular collagen or laminin B2 gene expression.

A study was designed to clarify the effects of captopril (CAP) or nitrendipine (NITR) on cardiac hypertrophy and left ventricular expression of the laminin B2 or collagen (COL) gene in spontaneously hypertensive rats (SHRs). Cardiac weight was significantly increased in 20-week-old SHRs. Gene expression of the alpha 1 chain of type IV COL determined by northern blot analysis decreased with age in Wistar-Kyoto rats and SHRs. Left ventricular laminin B2 mRNA was decreased at 12 weeks and increased again at 20 weeks in both strains. Daily oral administration of CAP (40 mg/kg, n = 5) or NITR (30 mg/kg, n = 4) to SHRs from 8 to 20 weeks decreased blood pressure to 142 mmHg (p < 0.01 vs 197 mmHg in controls, n = 5). Cardiac weight was 1.26 +/- 0.04 (SE) g in controls and was reduced to 1.03 +/- 0.05 g (p < 0.01) by CAP, but not by NITR (1.24 +/- 0.04). Left ventricular laminin B2 gene expression was attenuated by CAP and NITR to 41% and 32% of the control value, respectively. CAP significantly decreased left ventricular alpha 1 type IV COL mRNA to 11% of the control level, whereas NITR caused a reduction only to 75%. CAP also decreased alpha 1 or alpha 2 type I COL mRNA. These results suggest that angiotensin converting enzyme inhibitors prevent and/or cause regression of cardiac hypertrophy by inhibiting the gene expression of extracellular matrix, and that angiotensin II may have a pivotal role in cardiac hypertrophy.

Animals↗

PubMed1993

[Estimation of nitrogen-corrected metabolizable energy value of laboratory canine diets].

This study evaluates the reliability of the equation, metabolizable energy (ME) = digestible energy (DE) - 1.25 x digestible crude protein (DCP), as a means of estimating the energy value of non-purified diets for laboratory dogs. To do this, five digestion and nitrogen-balance (NB) trials and determination of the energy value of a diet were conducted using five diets and four mature, male Beagles for each experiment. The resulting digestibility of crude protein, acid ether extract, and nitrogen-free extract of these diets were 79.5%, 91.6%, and 84.8%, respectively. The NB in every diet was positive: 1.4-8.6 mg/g dry matter of ingested diet. Of the nitrogen (N) ingested, 21% was excreted into feces, 66% was excreted into urine, and 13% was retained. In terms of dietary gross energy (GE), 18% was lost in feces and 5% was excreted into urine leaving 77% as ME. Retained energy in the body was only 1%, and N-corrected metabolizable energy (MEn) was 76% of GE. The average urinary energy (UE) loss per gram of urinary N was 7.84kcal. The correlation between UE/DCP and NB values is statistically significant: UE/DCP = 1.24-0.03NB, r = 0.798, P < 0.001. Therefore, UE/DCP is 1.24kcal/g at N-equilibrium, almost the same as the factor in the above equation. The ME value calculated by the equation is identical to the MEn value and both are significantly lower (P < 0.05) than the empirically determined ME value.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Nutritional Physiological Phenomena↗

PubMed1993

[Mental health, work environment, and health practices among middle-aged male workers].

A study was made on the cross-sectional relationship of the psychosocial work environment and personal health practices to mental health level among 15,639 male subjects aged 30-59 engaged in various kinds of occupations and firms. Mental health level was dichotomized by self-reported mental disorders. The psychosocial factors of work environment were conceptually constructed from the aspects of working conditions and occupational stress. Working conditions were assessed by work overload, work shifts and role in the organization. Occupational stress was measured by psychological work load and job characteristics (job demands and decision latitude). Various factors associated with positive health behavior--an index based on six parameters such as supper time, physical exercise, smoking, alcohol consumption, sleep, and weight--were examined. The prevalence of self-reported mental disorders was 17.5 per 1,000 population. Multiple logistic analysis showed that both psychological work load and health practice index have a significant independent effect on mental health levels after controlling for age and marital status. Limitations of the present study indicate a need for future longitudinal studies.

Adult↗

PubMed1993

Multiple myeloma occurring in early stage primary biliary cirrhosis.

B-cell neoplasms are not infrequently associated with autoimmune diseases. A 60-year-old man with multiple myeloma developing in an early stage primary biliary cirrhosis was reported. Initially, he had hypergammaglobulinemia with monoclonal gammopathy (IgG-kappa type), elevation of serum IgG and IgM, and positive serum antimitochondrial antibodies. There were compression fractures of the lumbar vertebrae, where bone marrow aspiration revealed proliferating myeloma cells. Liver biopsy revealed destruction of bile duct surrounded by an inflammatory infiltrate, which was consistent with stage I primary biliary cirrhosis. The association suggested the role of immunoregulatory abnormalities in the development of multiple myeloma.

Bone Marrow↗

PubMed1993

Three-dimensional structure of dog Sertoli cells: a computer-aided reconstruction from serial semi-thin sections.

The three-dimensional structure of the Sertoli cell in the Korean Jindo dog was investigated by scanning and transmission electron microscopy. Additionally, type-A and type-B Sertoli cells were simulated by three-dimensional computer graphic imaging to clarify the anatomical relationship between Sertoli cell and germ cells. Descriptions in the present study are based on examination of the reconstructed type-A cells at stages IV, V and VI of the spermiogenetic cycle and stages VII, VIII and IX of the reconstructed type-B Sertoli cells. Morphologically, three types of Sertoli cell processes were evident: 1) flat club-like, elliptical processes bifurcating and trifurcating randomly; 2) slender cord-like, tubular processes; and 3) sheet-like processes. The sheet-like processes rested upon more than half the surface of each round spermatid located in the proximity of the Sertoli cell. Curiously, just before spermiation, the apical club-like processes shifted from their initial position at the spermatid head and subsequently covered the disengaged residual body, after which the residual body was no longer evident in the tubule. Though the mechanism for this elimination is not known, the process suggests a reciprocity between the Sertoli and germ cells. An anatomical dissimilarity between type-A and type-B Sertoli cells appeared in the apical region, with the apical club-like processes of the type-B Sertoli cell given off by sheet-like processes as well as by the Sertoli column. At the base of all Sertoli cells, sophisticated sheet-like processes paralleled the basal lamina, tenaciously adhering end-to-end to the sheet-like processes of adjacent Sertoli cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

An adult case with multiple cardiac valve prolapse and regurgitation.

A 56-year-old female had pure regurgitation in all cardiac valves. Color Doppler echocardiography showed a regurgitant jet in all cardiac valves. The severity of regurgitation due to the prolapse in all valves was moderate. The patient had no history of rheumatic fever, ischemic heart disease, endocarditis or hypertension. Physical characteristics of the patient were neither of Marfan's nor Ehlers-Danlos' syndrome. The etiology of regurgitation in all cardiac valves of this patient may be due to multiple valve prolapse.

Aortic Valve Insufficiency↗

PubMed1993

Sudden cardiac death from hypertrophic cardiomyopathy and acute idiopathic (Fiedler's) myocarditis: autopsy report.

A 45-year-old man with a rapidly deteriorating heart condition died suddenly, two hours after admission, after resistance to attempts of cardiac pacing. At autopsy, the heart weighed 600g with asymmetric septal hypertrophy. Histological examination revealed an extensive and diffuse disarray of myocardial fibers in the ventricular septum and in the free wall of both ventricles. Pronounced mononuclear cell infiltrations and interstitial edema were distributed widely in both ventricles. There were few abnormal findings in the other organs. The diagnosis was hypertrophic cardiomyopathy accompanied by Fiedler's myocarditis. Such a case appears to be rare.

Cardiomyopathy, Hypertrophic↗

PubMed1993

Role of 830 nm low reactive level laser on the growth of an implanted glioma in mice.

The effect of low reactive level laser therapy (LLLT:830 nm, 60 mW, continuous wave) was studied using the model of a glioma implanted in mice. Two different models were used. In the first model, therapies were applied post the first day of glioma implantation; in the second model, post the fourteenth day of glioma implantation. Using the first model, therapies were designed as follows. 1) control group (no therapy), 2) direct LLLT (15 seconds twice per day; on the skin covering the implanted glioma), 3) indirect LLLT (15 seconds twice per day; on abdominal skin area rather than the site of the implanted glioma), 4) indirect LLLT (30 seconds twice per day), 5) anti-cancer drug (ACNU) group, 6) mouse beta-interferon (Mu-beta-IFN) group, 7) direct LLLT plus Mu-beta-IFN group, 8) ACNU plus Mu-beta-IFN group, 9) indirect LLLT (15 seconds twice per day) plus ACNU plus Mu-beta-IFN group. Using the second model, therapies were designed as follows. 1) control group (no therapy), 2) indirect LLLT (15 seconds twice per day), 3) indirect LLLT (15 seconds twice per day) plus Mu-beta-IFN group, 4) Mu-beta-IFN plus ACNU group. Our results indicated that, applied on the first day after glioma implantation, both direct and indirect LLLT were effective in inhibiting the tumor growth. In addition, it appeared that the effect of LLLT might be dose-dependent. Finally, the group of direct LLLT plus Mu-beta-IFN was most effective in limiting the tumor growth and the incidence of growth as compared with the other groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Differential sensitivity to interleukins of CD5+ and CD5- anti-DNA antibody-producing B cells in murine lupus.

We studied the effects of interleukins (IL) on in vitro IgM and IgG anti-DNA antibody production by splenic B cells from autoimmune disease-prone NZBxNZW (NZB/W) F1 mice. It was found that different interleukins regulate phenotypically distinct B cells producing separate isotype of anti-DNA antibodies. IL-2 slightly but significantly inhibited the production of IgM anti-DNA antibodies. IL-4 and IL-6 significantly enhanced the antibody production, but the effects were not so marked and inconsistent, particularly with respect to IL-6. By contrast, the effects of IL-5 were remarkable, particularly on splenic B cells from young mice. As for IgG anti-DNA antibodies, IL-6, but not other interleukins, markedly up-regulated the antibody production by splenic B cells from mice over 6 months of age, in a dose dependent fashion. Thus, the ability of B cells to produce IgG anti-DNA antibodies appears to be dependent on the surface expression of IL-6 receptor (IL-6R) at the ages when the mice begin to develop the disease. Studies of the surface phenotypes showed that while the IL-5-sensitive major IgM anti-DNA producers were CD5+Lp-3(CD43)-sIgM+, the IL-6-sensitive major IgG anti-DNA producers were CD5-Lp-3+sIgM-. However, significant amounts of IgG antibodies were also produced, in the presence of IL-6, by CD5+Lp-3+sIgM+, but not by CD5-Lp-3+sIgM+ B cells from 6-month-old mice. We suggest that surface phenotypes of anti-DNA antibody producers change from CD5+Lp-3-sIgM+IL-5R+, CD5+Lp-3+sIgM+IL-6R+ and subsequently to CD5-Lp-3+sIgM-(sIgG+)IL-6R+ in NZB/W F1 mice with aging.

Animals↗