Search PubMed⌕ Search

Biomedical subjects

J Yamamoto

Publications and source records attributed to J Yamamoto.

At least 325 records · Page 18Linked to original sources

[IgE-Fc receptor expressions on bronchoalveolar lavage (BAL) cells in a patient with eosinophilic pneumonia accompanied with bronchial asthma--the effect of ketotifen on their expression].

In this study, IgE-Fc receptor expressions on each type of BAL cells (lymphocytes, macrophages and eosinophils) in a patients with eosinophilic pneumonia accompanied by bronchial asthma were examined by indirect immunofluorescent method using monoclonal antibody (H107). BAL cell findings showed marked increases of total BAL cell counts and eosinophils, an increased number of lymphocytes and the presence of basophilic cells. These results match those of our previous report. Furthermore, IgE-Fc receptor expressions on lymphocytes, macrophages and eosinophils were markedly increased as compared to those in the peripheral blood and normal control subjects. These findings suggest that IgE production in the lung plays the main role in the pathogenesis of eosinophilic pneumonia and bronchial asthma. On the other hand, during ketotifen administration, decreases of peripheral blood eosinophilia, of eosinophilia in the sputum and of serum IgE level and an improvement in chest X-ray findings were observed. Furthermore not only normalization of total BAL cell counts but also decreases of IgE-Fc receptor expressions on BAL cells were observed.

Adult↗

Severe hypoplasia of lymphoid tissues in Mo1 deficiency.

A lymph node was examined from a 4-year-old female child with documented "Mo1" (CR3) deficiency. There was hypoplasia of the lymph node, with small, poorly delineated germinal centers and overall lymphopenia. Retrospective analysis of the clinical course of a decreased elder sister of the index patient indicated that the elder sister probably also had "Mo1" deficiency. Review of findings at autopsy revealed severe hypoplasia of all lymphoid organs with lymphopenia. Our observations suggest that lymphoid tissue hypoplasia may be a feature of CR3 deficiency and is likely a result of the defective lymphocyte adherence functions to endothelium associated with absent lymphocyte function-associated antigen (LFA-1).

Antigens, Differentiation, T-Lymphocyte↗

Blood pressure and metabolic effects of streptozotocin in Wistar-Kyoto and spontaneously hypertensive rats.

There are conflicting reports regarding the action of streptozotocin (STZ) on blood pressure (BP) in rats. This study investigated the BP, metabolic and hormonal effects of increasing doses of STZ in Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR), with consideration to methodological aspects. Indirect tail-cuff systolic BP measured in a conscious state was mildly elevated after 2 to 4 weeks and remained so in severely diabetic, emaciated WKY, whereas there were no changes in the SHR. Four and 20 weeks after STZ administration, systolic, mean and diastolic BPs measured in a conscious state with an arterial catheter were unchanged in the diabetic WKY and were decreased in the diabetic SHR. Thus, the changes in BP depended on the method used. Dose-dependent increases in blood glucose were similarly evident under conscious and ether-anesthetized conditions. Triglycerides were increased, and blood insulin and thyroxine levels were decreased in both strains. Between-strain comparisons revealed that the hypoinsulinemic response was similar, but the hyperglycemic and hypertriglyceridemic responses were greater in the SHR. The findings provide a data base for further investigation on STZ diabetes. In addition, the results suggest a different BP and metabolic susceptivity to STZ treatment in the SHR and WKY.

Animals↗

Effects of moderate diabetes on cardiac performance in spontaneously hypertensive and Wistar-Kyoto rats.

To assess the effects of imposition of moderate diabetes on in vivo cardiac performance in gradually proceeding hypertension, spontaneously hypertensive (SHR) and Wistar-Kyoto rats (WKY) were treated with streptozotocin (40 mg/kg) or vehicle at 8 weeks of age. Four and 20 weeks later, with the rats under ether anesthesia, peak cardiac output and stroke volume were measured during volume loading and peak left ventricular developed pressure and maximum rate of rise of pressure (dP/dtmax) were determined during aortic occlusion. Additionally, passive pressure-volume relations were obtained during saline infusion in potassium-arrested hearts, and the chamber stiffness constant was derived from one exponential function. There was a mortality of 16.1% in the diabetic SHR only. While basal and stressed cardiac performance was unchanged despite the already decreased mean arterial pressure and left ventricular weight at 4 weeks, the diabetic SHR revealed significant decreases in peak cardiac pumping indexes, peak left ventricular developed pressure, and dP/dtmax, with unchanged resting cardiac function, at 20 weeks. Changes seen in the diabetic WKY were reduced left ventricular weight at 4 weeks and reduced peak left ventricular dP/dtmax at 20 weeks. The chamber stiffness was unaltered with strain or diabetes. These data show that imposition of even moderate diabetes substantially influences the stress-loaded in vivo cardiac performance in the SHR, whereas it produces only minor changes in the WKY.

Animals↗

Roles of cholinergic, dopaminergic, noradrenergic, serotonergic and GABAergic systems in changes of the EEG power spectra and behavioral states in rabbits.

In the present study, the influences of cholinergic (ACh), dopaminergic (DA), noradrenergic, serotonergic and gamma-aminobutyric acid (GABA) ergic system activation and blocking agents on the cortical (CT) and hippocampal (HC) EEG power spectra were investigated in rabbits. The AChergic agents, physostigmine and atropine, produced marked increases or decreases in peak powers, the changes of which were inversely related to each other, but similar to those of the normal behavioral states. The other agents did not always produce changes. ACh seems to play an important role in the regulation of peak powers. Apomorphine shifted the theta wave peak to higher frequencies and haloperidol shifted it to lower frequencies. The other drugs did not cause a shift. DA seems to regulate peak frequency. These findings suggest that ACh is important for the regulation of consciousness between the wakefulness and SWS states and suggest that DA is involved in the production of REM sleep.

Acetylcholine↗

Acquisition and functional analysis of manding with autistic students.

Three autistic students were trained to request a specific object from an adult "supplier" with the sentence, "Give me--" and to deliver that object to another adult, the "director." Subsequently, the degree to which the object offered by the supplier controlled the "Give me--" verbal response was assessed by delivering to the student an object other than the one requested. Despite knowing the names of all objects used in the experiment, students accepted and delivered to the director any object offered by the supplier regardless of its match with the requested object. After training to say "That's not it. Give me--" when nonrequested objects were offered, students responded differentially to requested and nonrequested objects, suggesting control of the "Give me--" response by the requested object, a characteristic of a mand. These results generalized across settings and objects. Results are discussed in terms of the training technique to establish manding and the functional analysis of the resulting verbal behavior.

Autistic Disorder↗

New modified activated partial thromboplastin time and prothrombin time methods using a synthetic chromogenic substrate in combination with diazotization.

A chromogenic substrate, H-D-Phe-Pip-Arg-pNA (S-2238) is a highly specific substrate to thrombin and releases p-nitroaniline (pNA) by the action of thrombin. We describe new modified APTT and PT methods using S-2238 in combination with the diazotization of pNA. In the modified APTT method, 100 microliter citrated plasma (diluted to 10-fold), 90 microliter 1 mM S-2238, 100 microliter 20 mM CaCl2 and 100 microliter Actin were mixed in an ice-bath, then incubated for 8 min at 37 degrees C. The reaction was stopped, and the generated pNA was diazotized by adding the following solutions sequentially: 975 microliter 0.04% sodium nitrite, 975 microliter 0.3% ammonium sulfamate and 975 microliter 0.07% N-(l-naphthyl)-ethylenediamine dihydrochloride. Diazotization changed pNA from yellow to pink. Then, absorbance at 545 nm was read, and values were expressed as thrombin units/ml plasma. In the modified PT method, 100 microliter citrated plasma (diluted to 20-fold), 90 microliter 1 mM S-2238 and 200 microliter tissue thromboplastin-C solution were mixed and processed as above. Correlations of the present modified APTT and APTT methods, and of modified PT and PT methods were significant (r = 0.426, p less than 0.01 and r = 0.561, p less than 0.01, respectively).

Aniline Compounds↗

Variation in the frequency and type of sperm chromosomal abnormalities among normal men.

The chromosomal constitution of 1582 human sperm from 30 normal men of proven fertility was investigated after sperm penetration of hamster eggs. A minimum of 30 sperm chromosome complements were analysed per donor so that the distribution and variation in the frequency and type of sperm chromosomal abnormalities could be assessed. The mean frequency of sperm chromosomal abnormalities in individual men was 10.4% (+/- 6.0%) with a range of 0-24.7%. For numerical abnormalities the mean was 4.7% (+/- 2.9%) with a range of 0-10% and for structural abnormalities the mean was 6.2% (+/- 6.0%) with a range of 0-23.1%. The 95% confidence intervals for the mean of an individual male were 0-10.5% for numerical abnormalities, 0-18.2% for structural abnormalities, and 0-22.4% for total abnormalities. There was a significant excess of hypohaploid complements compared with hyperhaploid complements. Since hypohaploid complements could be caused by technical artefact, a conservative estimate of aneuploidy was obtained by doubling the frequency of hyperhaploid sperm, yielding an estimate of 2.4% aneuploidy. The proportion of X-bearing (53%) and Y-bearing (47%) sperm did not differ significantly. These results were compared to the other two large studies of sperm chromosome complements from normal men.

Adult↗

Incidence and some characteristics of fimbriae FY and 31A of Escherichia coli isolates from calves with diarrhea in Japan.

Escherichia coli isolates from calves with diarrhea (1 day to 8 weeks old, 140 individuals) were surveyed for the three immunologically distinct fimbrial adhesins FY, 31A, and K99. Of a total of 1,370 strains isolated, 96 (7.0%), 34 (2.5%), 75 (5.5%), and 13 (0.9%) were identified as FY+, 31A+, FY+.31A+, and K99+, respectively. The K99+ strains also manifested heat-stable enterotoxin production (ST+), while FY+, 31A+, and FY+.31A+ strains were ST-. Expression of FY and 31A was repressed at lower temperatures or poor aeration. The FY+ and 31A+ E. coli showed mannose-resistant hemagglutinating activity with bovine erythrocytes. Electron microscopy revealed that FY is a gently curled fimbria with a mean diameter of 4.2 nm, and 31A is a fimbria with a mean diameter of 5.1 nm. The molecular mass of protein subunits was found to be approximately 20 kilodaltons (Kd) and 19 Kd for FY and 31A, respectively. Lethal diarrhea of neonatal calves was induced by challenge with the combination of a K99+.ST+ E. coli strain and either a 31A+ E. coli strain or a 31A+ E. coli strain plus an FY+ E. coli strain under the experimental conditions in which lethal diarrhea was not induced by challenge with a K99+.ST+ E. coli strain alone.

Adhesins, Escherichia coli↗

Increase of nonplasmin fibrinolytic activity in the lung and spleen of streptozotocin-induced diabetic rats.

In streptozotocin-induced diabetes in rats, nonplasmin fibrinolytic activity was found to be significantly increased in the lung and spleen, but not in the liver and kidney. The plasminogen-activator activities, either soluble or insoluble, were almost simultaneously increased in the lung, suggesting the possible release of plasminogen-activator from the lung to the blood. It seems likely that plasminogen-activator of the usual type and nonplasmin protease are also involved in thrombotic disorders in the experimental diabetes.

Animals↗

Cardiovascular responses to acute stress in young-to-old spontaneously hypertensive rats.

Age-related changes in circulatory responses to short-term shaker stress were investigated in conscious spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). Hemodynamics (microspheres) were measured at 8, 24, 48, and 96 weeks of age, and plasma catecholamines were measured at 8 and 96 weeks. At rest, elevated mean arterial pressure was associated with unaltered cardiac index and heart rate in SHR compared with WKY at all ages. Regional blood flow was largely similar in both strains, except for a reduced renal flow in 96-week-old SHR. Cardiac index and most regional blood flow tended to or did decline in both strains between 8 and 96 weeks. Plasma catecholamines were similar in both strains at 8 and 96 weeks. Shaker stress evoked responses similar to defense reactions in both strains. The incremental responses in mean arterial pressure, heart rate, cardiac index, and cerebral, skeletal muscle, and myocardial flow and the decremental responses in splanchnic, renal, and skin flow were greater in SHR than in WKY, particularly at 8 weeks. Most of these responses tended to or did decline between 8 and 96 weeks in both strains. The plasma catecholamine responses were also greater in SHR at 8 and 96 weeks, and they did not differ in either strain between these ages. Thus, circulatory and sympathoadrenal reactivity to acute stress were enhanced in SHR compared with WKY, independently of age.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗

[A case of a male gastric choriocarcinoma with massive mesenteric tumor and review of the literature on male choriocarcinoma].

A 32-year-old man was admitted to our hospital, complaining of an abdominal mass. An operation disclosed a large tumor, the size of a child's head, in the mesenterium of the transverse colon, with a multiple liver metastasis. A tumor resection was performed and, histologically, the tumor was diagnosed as being a choriocarcinoma. Gynecomastia was not observed. The patient died 2 months after this operation in spite of chemotherapy. An autopsy disclosed metastatic choriocarcinomas in the lungs, the liver, the peritoneum, the stomach, the adrenal glands and in the lymph nodes. The testis was found to be normal by a serial histological examination. Primary advanced adenocarcinoma, which is histologically similar to a choriocarcinoma, was found in the stomach. This case was finally diagnosed as being a gastric adenocarcinoma which showed choriocarcinomatous differentiation at various metastatic sites.

Adenocarcinoma↗

Patient requests: correlates and therapeutic implications for Hispanic, black, and Caucasian patients.

A patient's reason for coming to a psychiatric outpatient clinic (his/her request for service) should be the focal point as a therapist develops an appropriate therapeutic plan for that patient. Data have been collected on 173 Hispanic, Black and Caucasian patients with regard to their reasons for coming to the clinic and selected demographic and process/outcome variables. A factor analysis of the patient request data generated three conceptual factors, which account for 13 reasons for coming to the clinic. The relationship of these factors with selected demographic and therapy outcome variables was tested statistically, and implications for therapy with low income and minority patients are discussed.

Adult↗