Search PubMed⌕ Search

Biomedical subjects

H Ogata

Publications and source records attributed to H Ogata.

At least 307 records · Page 17Linked to original sources
PubMed1992

Gastric emptying rate of drug preparations. III. Effects of size of enteric micro-capsules with mean diameters ranging from 0.1 to 1.1 mm in man.

The gastric emptying rates of three enteric micro-capsule preparations with mean diameters of 1.1 mm and less (1.1, 0.5 and 0.1 mm) were compared. The gastric emptying rate was evaluated by determining the pharmacokinetic parameters of pyridoxic acid, including Vmax (peak excretion rate) and Tmax (time to reach peak excretion rate) after oral administration of micro-capsules containing pyridoxal phosphate as a marker drug to five healthy subjects. When given under fasting conditions, the gastric emptying rates of these preparations, according to Tmax, differed significantly; the preparations with smaller particle sizes were emptied from the stomach at a faster rate than those with larger particle sizes. However, under non-fasting conditions the gastric emptying rates were virtually the same, regardless of particle size, and all the preparations were emptied from the stomach at a much slower rate than when administered under fasting conditions.

Adult↗
PubMed1992

Late results after repair of complete atrioventricular canal.

Twenty-five patients with complete atrioventricular canal including 10 Down's syndrome patients repaired since 1972 were analyzed with respect to their physical activities, hemodynamics, ECG, reoperation and late mortality. Follow-up period ranged from 1 to 17 years with an average of 7.0 years. There was 1 late death. Actuarial survival rate was 0.86 +/- 0.13 (mean +/- S.D.) at 12 years. Fourteen patients (70%) of 20 evaluated were in New York Heart Association functional class I, and 4 (20%) were in class II and 2 (10%) in class III. In 23 patients without pulmonary stenosis, preoperative values of peak pulmonary to systemic pressure ratio (Pp/Ps) and pulmonary to systemic arterial resistance ratio (Rp/Rs) were 0.64 +/- 0.28 and 0.36 +/- 0.31, respectively. Postoperative Pp/Ps and Rp/Rs significantly decreased to 0.37 +/- 0.14 and to 0.20 +/- 0.14, respectively. In Down patients, postoperative Pp/Ps, Rp/Rs and pulmonary arterial resistance were significantly greater than in non-Down patients (0.50 +/- 0.07 vs. 0.25 +/- 0.05, 0.30 +/- 0.13 vs. 0.10 +/- 0.03 and 4.4 +/- 1.8 vs. 1.8 +/- 0.6 units.m2, respectively). Complete heart block developed in 1 patient postoperatively. Sick sinus syndrome was observed in 3 patients, transient Mobitz II A-V block in 2, ventricular premature contractions of Lown's Grade II in 1 and atrial fibrillation in 1. Five patients demonstrated severe mitral regurgitation equal to or more than Grade III and 2 of them underwent mitral valve regurgitation equal to or more than Grade III and 2 of them underwent mitral valve replacement 6 months and 12 years after the initial operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

The mechanism of action of serum immunosuppressive factor in Crohn's disease: it blocks the growth of mitogen-stimulated lymphocytes in early G1 phase through an inhibition of transferrin receptor expression.

The presence of serum immunosuppressive factor has recently been reported in patients with Crohn's disease. We investigated the mechanism of action of this immunosuppressive factor in vitro. The factor in serum fraction from patients with Crohn's disease had an inhibitory activity on the proliferation of phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMCs) from healthy volunteers. The growth of tumor cell lines, however, was not inhibited by the factor. While the factor did not influence the production of interleukin 2 (IL2) or the expression of IL2 receptor of PHA-stimulated PBMCs, it inhibited the expression of transferrin receptor. The effect of the factor on cell cycle of PHA-stimulated PBMCs was examined by flow cytometry analysis. The factor kept the cells in quiescent G0/G1 phase and decreased the number of cells in S phase. Prostaglandin E2, an immunosuppressive substance, may not participate in the inhibitory action of the factor, since indomethacin did not affect the inhibitory activity of the factor. These results suggest that the immunosuppressive factor in serum from patients with Crohn's disease is unique in the mechanism of inhibitory action and further clarification of this factor might contribute to the development of a new diagnostic assay for Crohn's disease and the elucidation of the pathogenesis of this disease.

Cell Cycle↗
PubMed1992

[Clinical aspects of acid-base disorders].

Acid-base disorders are frequently recognized in a wide variety of clinical settings such as severe systemic hospitalized patients. The principal object is to assessment of acid-base equilibrium and to obtain an appropriate guide to therapy. The approach is centered to a systemic analysis of blood gas evaluation. To establish this complex matter is followed. Is an acid-base disorder present? Is the disorder a simple or a mixed abnormality? What is the primary cause? These evaluations should be obtained by accurate history taking, physical examination, and routine laboratory tests. In addition, the supporting analysises such as anion gap (AG) calculation, urine AG assessment, urine chloride concentration and so on are also useful for correct diagnosis. In view of the complexty and difficult expression of acid-base disorders, it is desirable that clinicians must have full knowledges of systemic approach to the blood gas analysis and its evaluation.

Acid-Base Imbalance↗
PubMed1992

[Differences of regional blood flow after stellate ganglion block with local anesthetic and that after stellate ganglion resection using ultrasonic Doppler flowmeter].

Ten mongrel dogs were divided into two groups; stellate ganglion block (SGB, n = 5) group and stellate ganglion resection (SGR, n = 5) group. Anesthesia was induced with pentobarbital 25 mg.kg-1. The animals were mechanically ventilated to maintain a constant PaCO2 (35-40 mmHg). Left common carotid arterial flow (CCAF), left external carotid arterial flow (ECAF), left vertebral arterial flow (VAF) and left brachial arterial flow (BAF) were measured using an ultrasonic transit time flowmeter. Internal carotid arterial flow (ICAF) was calculated by subtracting ECAF from CCAF. After thoracotomy, the first SGB with 0.5% mepivacaine 1.5 ml or SGR was performed. Ninety minutes after the first SGB, the second SGB was performed. The data were taken for 180 minutes after the first SGB or SGR. In SGB, CCAF and BAF increased significantly for the duration of action of local anesthetic. But VAF and ICAF increased significantly for a short time after the block. In SGR, CCAF, BAF and ICAF increased significantly during the experiment. But VAF showed a transitory increase immediately after the resection. The authors conclude that sympathetic ganglion block with local anesthetic should be performed repeatedly when increase of blood flow in blood vessels with strong autoregulation from the brain is anticipated.

Animals↗
PubMed1992

[The effects of 20% saline solution on the circulatory dynamics during the hemorrhagic shock state].

This experiment was performed to study the effects of administration of 20% saline solution 1.5 ml.kg-1 on the circulatory dynamics during the hemorrhagic shock state. Administration of 20% saline solution 1.5 ml.kg-1 during the hemorrhagic shock produced twofold increase of the mean arterial blood pressure for one hour, 2.5 fold increase of the cardiac output, increasing tendency in the mean pulmonary arterial pressure, central venous pressure, and the heart rate, accompanied by decrease in total peripheral resistance and the pulmonary blood vessel resistance. There were no improvements in acidosis and hematocrit. These data suggest that the circulatory improvements after the administration of 20% saline solution depend on an increase in cardiac output as the result of improvements in both pre- and after-load, but not of plasma volume expansion. The results also suggest that the administration of 20% saline solution 1.5 ml.kg-1 is useful for an emergency case with acute circulatory insufficiency or for emergency resuscitation.

Animals↗
PubMed1992

Enrichment of murine bone marrow natural suppressor activity in the fraction of hematopoietic progenitors with interleukin 3 receptor-associated antigen.

Natural suppressor (NS) activity has been identified in several sites of active hematopoiesis. In this study we characterized NS activity in murine bone marrow (BM) using monoclonal antibodies (mAbs) to interleukin 3 (IL-3) receptor-associated antigen (IL-3RAA) and various cytokines that exert a strong influence on hematopoiesis or lymphocyte interaction. NS activity of BM cells of relatively low density was enhanced by IL-3 or granulocyte-macrophage colony-stimulating factor (GM-CSF). When the BM cells were separated into IL-3RAA+ cells and IL-3RAA- cells, the IL-3RAA+ cells demonstrated potent NS activity, whereas IL-3RAA- cells had either no or weak NS activity. The IL-3RAA+ cells showed non-T- and non-B-cell phenotype and had high affinity to wheat germ agglutinin (WGA), a marker for hematopoietic progenitors. In assays for hematopoietic activity, it appeared that the early differentiating progenitors (day 8 spleen colony-forming units [CFU-S], granulocyte-macrophage colony-forming units [CFU-GM]) were enriched in the IL-3RAA+ cell population, whereas more immature multipotent progenitors (day 12 CFU-S, granulocyte erythrocyte macrophage megakaryocyte colony-forming units [CFU-GEMM]) were contained in the IL-3RAA- cell population. Both suppressor cells and IL-3RAA+ cells spontaneously developed from the IL-3RAA- cell population. These findings suggest that NS cells in murine BM are early hematopoietic progenitors and are probably committed to the myeloid lineage. Hybridoma cells established between the IL-3RAA+ cells and BW5147 cells produced suppressor factor(s). This finding suggests that the NS cells produce soluble mediator(s) that may be responsible for their suppressive action.

Animals↗
PubMed1992

[Surgical repair of coarctation of the aorta during infancy].

Fourty-six infants less than 1 year of age underwent repair of coarctation of the aorta in our institution between 1972 and 1991. Pathologic types and numbers of patients were simple coarctation (Group 1) in 7 patients, with ventricular septal defects (Group 2) in 22 patients and with complex cardiac anomalies (Group 3) with 17 patients. A patent ductus arteriosus was present in 43 of these patients. Operative technique used were resection and end-to-end anastomosis (RETE) in 30 patients, subclavian flap angioplasty (SFA) in 15 and Blalock-Park operation in one patient. RETE procedures were employed from 1972 until 1980 and SFA procedures were employed between 1981 and 1985. After 1986 RETE procedures were employed again. The operative mortality rates were 0% (0/7) in Group 1, 9.1% (2/22) in Group 2 and 82.3% (14/17) in Group 3. The high mortality rate in Group 3 are thought to be related to severe associated cardiac anomalies. There were no significant differences in the operative mortality and recurrent coarctation rates between RETE and SFA procedures in Group 1 and 2. In patient with a large associated intracardiac shunt (Group 2 and 3) banding of the main pulmonary artery (PAB) was performed with coarctectomy simultaneously. In Group 2 VSD closure and debanding could be done a few months later with excellent results, but in Group 3 primary repair of cardiac anomalies may be worth to try since results of coarctectomy with palliative procedures in these group of patients were poor.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗
PubMed1992

[A case of localized pleural mesothelioma containing a wedge-shaped area of aeration].

A 32-year-old man was admitted to our hospital because of an abnormal shadow on the chest X-ray film, which was detected on mass survey. The chest X-ray film on admission revealed an irregular mass shadow in the pleural layer between the left upper lobe and the lower lobe, and this shadow had a wedge-shaped area of aeration inside it. Needle biopsy under ultrasonography suggested a localized pleural mesothelioma. Surgery to resect the tumor revealed that it was pedunculated and had developed from the pleura of the left S5 segment. The resected specimen showed lung tissue invaginating into the tumor through a concave area of the tumor. The chest X-ray findings of this case are very unusual, and we were unable to find a similar case of localized pleural mesothelioma in the literature.

Adult↗
PubMed1991

Analyses of T-cell differentiation from hemopoietic stem cells in the G0 phase by an in vitro method.

Using differential radiation sensitivity of components of mouse embryonal thymus, an in vitro method for studying T-cell differentiation from hemopoietic stem cells (HSCs) in the G0 phase was established. Intrathymic T-cell precursors present in embryonal thymus were found to be quite radioresistant (up to 20 Gy), and consequently 25-Gy-irradiated embryonal thymic lobes were used. Thymic lobes (25-Gy irradiated) taken from mouse fetuses (gestation day 15) were placed in Millipore-HA culture plates supported on squares of gelatin foam sponge in 24-well culture plates in which neonatal thymus stromal cells were cultured. HSCs (10(5) cells per well) in the G0 phase were added to these thymic lobes and cocultured at 37 degrees C in a 5% CO2/95% air incubator. Half the culture medium was changed every week. After 3 weeks, a large number of colonies had formed. Immunohistochemical studies and fluorescence-activated cell sorter analyses revealed that the colonizing cells regularly develop and exhibit surface markers characteristic of T cells (Thy-1, IL-2R, L3T4, Lyt-2, etc.). In situ hybridization analyses revealed that mRNA expression for T-cell receptor (TCR) beta chains occurred within colonizing cells. Using a monoclonal antibody (F23.1), expression of TCR beta-chain variable domain (V beta 8) on the surface of these developing T cells was demonstrated. These cells responded to interleukin 2 and/or anti-CD3 monoclonal antibody, indicating functional T cells. This method will be useful in studying T-cell differentiation pathways from pluripotent HSCs and in clarifying the mechanisms involved in negative and positive selection of T cells within the thymus.

Animals↗
PubMed1991

[Supracondylar knee-ankle-foot orthosis for post-polio syndrome].

We report a 69-year-old female suffering from post-polio syndrome. Though she experienced acute poliomyelitis at one year of age, she had been well until 67 years of age when she complained of muscle weakness and pain in her right lower extremity and gait disturbance. As she was admitted to our hospital for further evaluation and rehabilitation, we prescribed for her the rehabilitation program consisting of gait training with a supracondylar knee-ankle-foot orthosis, low-load repetitive muscle strengthening exercises, and continuous stretching of her right knee joint after heat treatment. She regained a stable gait with the orthosis. We thought that the disuse and overuse of the lower extremities played a part in the onset of post-polio syndrome and that the rehabilitation including the low-load repetitive muscle strengthening exercises and gait training with a supracondylar knee-ankle-foot orthosis was effective against her disability.

Aged↗
PubMed1991

Non-Hodgkin's lymphoma confined to the nasal cavity: its relationship to the polymorphic reticulosis and results of radiation therapy.

From 1975 through 1988, nine patients with locally confined nasal non-Hodgkin's lymphoma (NHL) were treated with radiation therapy in the Department of Radiology, Chiba University Hospital. Immunohistochemical study disclosed that all NHL's have T-lineage. Additionally, unique histological pictures of polymorphism, angiodestruction, and necrosis were seen in most of cases. These three findings are the histological features of polymorphic reticulosis (PMR), which is the main cause of lethal midline granuloma and has recently been shown to belong to T-cell malignancy. Therefore, it is concluded that the nasal T-cell NHL and PMR are really a single disease entity. The predominance of the T-cell lymphoma in the nasal cavity as well as its histological distinctness clearly indicate that the head and neck extranodal NHL cannot be discussed together. Although the disorder was considered to be locally limited at presentation, only 3 of the 9 patients with nasal NHL could be induced into long-term remission with involved field radiotherapy. The distant extranodal spread was the primary cause of failure. Multimodality treatment using intensive chemotherapy might improve the prognosis of nasal NHL.

Female↗
PubMed1991

Effect of food on the bioavailability of cyclandelate from commercial capsules.

The bioavailability of five capsules of cyclandelate that are commercially available in Japan was determined in ten healthy volunteers by measuring mandelic acid (a main metabolite of cyclandelate) excreted in the urine. Bioinequivalence among the five capsules was demonstrated. The relative cumulative excretion of mandelic acid of the most poorly bioavailable capsule was 38% of the most highly bioavailable capsule. The effect of food on the bioavailability of these two capsules was investigated by use of two different kinds of food, one containing fat and one containing high carbohydrates but very low fat. The bioavailability of the two capsules was increased when subjects consumed both types of food before drug administration, although there was a greater effect on bioavailability with food containing fat. This suggests that the absorption of cyclandelate was incomplete in fasting subjects, even from the capsule with the highest bioavailability. Bioinequivalence between the two capsules remained after postprandial drug administration.

Administration, Oral↗