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T Otsuka

Publications and source records attributed to T Otsuka.

At least 199 records · Page 11Linked to original sources
PubMed1994

Slightly altered permeability-surface area products imply some cerebral capillary recruitment during hypercapnia.

To test the capillary recruitment hypothesis in brain, cerebral blood flow was raised markedly in rats by exposure to 8% CO2 (hypercapnia), and capillary permeability-surface area (PS) products were measured. Local cerebral blood flow (LCBF), volume of radiolabeled blood in parenchymal microvessels (also referred to as the blood space or Vb), plus the local capillary influx rate constants (K1) and PS products of [14C]antipyrine and 3-O-[14C]methyl-D-glucose (3OMG) were estimated in 44 brain areas. Hypercapnia raised PaO2 to 140 mm Hg, elevated LCBF by two- to threefold through out the brain, and increased Vb from 5 to 33% (mean = 22%) in 42 of 44 brain areas; hypercapnia did not, however, alter microvessel hematocrit. With hypercapnia, the influx of antipyrine was increased by 40-65% in all brain areas, and the PS products of antipyrine were elevated from 0-35% (mean = 17%). The PS products of antipyrine plus the parenchymal blood spaces suggest modest (< 30%) capillary recruitment in most brain areas as well as some microvessel dilation, mainly in forebrain gray matter and white matter areas. In contrast, hypercapnia did not appreciably alter K1 nor PS of 3OMG; it slightly but not significantly raised the blood levels of glucose. In view of the blood space and antipyrine evidence for modest capillary recruitment and vasodilation, the lack of change in PS of 3OMG implies that glucose transporter activity was lowered by hypercapnia, an effect similar to that reported for high-dose pentobarbital. Finally, the microvessel hematocrit and 3OMG data suggest that cerebral capillary permeability (P) was not increased by hypercapnia. Overall, hypercapnia seems to increase LCBF mainly by raising the velocity of blood flow; capillary recruitment and dilation appear to play relatively minor roles in this flow increase.

3-O-Methylglucose↗
PubMed1994

Benzopurpurin and related compounds inhibit the binding of gp120 to galactosyl ceramide/sulfatide and infection of human immunodeficiency virus.

In an attempt to find compounds capable of inhibiting the binding and infection by human immunodeficiency virus type 1 (HIV-1) in neural cells, we studied the effect of benzopurpurin and related compounds on the binding of gp120 to galactosyl ceramide (GalCer) and sulfatide. In this report, we show that the binding of gp120 to GalCer and sulfatide is inhibited by benzopurpurin and related compounds. These compounds also inhibit the binding and entry of HIV-1 to neural cell line, SK-N-MC. Binding studies indicate that benzopurpurin and related compounds bind to gp120. Studies involving related compounds indicate that the minimal structure required for the inhibition is two naphthalene rings with amine or sulfonic acids attached to a central biphenyl molecule by an azo group. This approach will be useful for screening of potential anti-HIV compounds.

Antiviral Agents↗
PubMed1994

IL-10 inhibits prostaglandin E2 production by lipopolysaccharide-stimulated monocytes.

Since IL-10 has recently been shown to exhibit pleiotropic effects on human monocytes, it was of interest to determine the effect of this cytokine on prostaglandin E2 (PGE2) production by monocytes. Recombinant IL-10 (rIL-10) did not significantly affect PGE2 production by lipopolysaccharide (LPS)-unstimulated monocytes, but efficiently inhibited PGE2 production by LPS-stimulated monocytes. The inhibition by rIL-10 was achieved in a dose-dependent manner. Recombinant IL-4 also inhibited PGE2 production at the same degree as rIL-10. Viral IL-10 inhibited PGE2 production by monocytes in a similar fashion as did human rIL-10. Endogenously produced IL-10 was also shown to inhibit PGE2 production by LPS-stimulated monocytes. Kinetic studies showed that the inhibition by rIL-10 on PGE2 production was observed at least 3 h after LPS stimulation. Taken together, these results indicate that IL-10 may play an important role in modulating immunological responses via down-regulation of PGE2 production by monocytes.

Cells, Cultured↗
PubMed1994

Blunt traumatic rupture of the heart: an experience in Tokyo.

The present study was planned to clarify the characteristics of blunt traumatic cardiac rupture. We performed a retrospective analysis of 63 patients with blunt traumatic cardiac rupture during the period from April 1975 through February 1993. Six of nine patients arrived with recordable blood pressure, and injuries were detected by ultrasonography. Three patients underwent pericardiocentesis before surgery. Seven patients survived overall. The hemodynamics in all seven survivors were stabilized within 3 days after cardiac repair. The survival rate among the patients who arrived with blood pressure was 54%. A patient who fell from higher than 6 meters or a pedestrian hit by car and thrown as short a distance as 6.5 meters may have cardiac rupture. Ultrasonography is a useful, quick, and sensitive way to detect the presence of pericardial fluid. We prefer to do pericardiocentesis with a large-bore catheter under ultrasonographic guidance for continuous pericardial drainage rather than to create a subxyphoid pericardial window for cardiac tamponade.

Adolescent↗
PubMed1994

Primary pulmonary choriocarcinoma in a four month old boy complicated with precocious puberty.

A four month old boy with pulmonary choriocarcinoma, showing iso-sexual precocious puberty is reported. His serum human chorionic gonadotropin (HCG) was highly elevated. A round isolated tumor in the right lung, found by chest X-ray, magnetic resonance imaging and gallium scintigraphy, was removed surgically a month and a half after clinical manifestations were noticed. It was determined to be choriocarcinoma on the basis of histological findings and positive HCG on histochemical examination. Skull irradiation and chemotherapy (cisplatinum, vinblastine and bleomycin) had only a transient effect on reducing tumor size and normalizing the serum level of HCG. This case suggests that a more effective treatment regimen needs to be established.

Choriocarcinoma↗
PubMed1994

Symptoms and social adjustment of schizophrenic patients as evaluated by family members.

The purpose of this study is to reveal the relationship between family expressed emotion (EE) and family evaluation for symptoms and social adjustment of schizophrenic patients. Chronic schizophrenic outpatients in offshore islands under stationary therapeutic conditions were studied. For evaluation, the Five Minute Speech Sample (FMSS) for EE and the Katz Adjustment Scale (KAS) for family evaluation of patients were used. EE level was high among relatives who thought the patient was belligerent, negativistic, unstable or helpless. High-EE relatives tended to evaluate their patients' performance of social activities rather low and showed strong dissatisfaction with the patient's leisure activities. Moreover, a high emotional overinvolvement (EOI) value is more common in Japan than in other countries. A subgroup of the FMSS-EOI, the emotional display, was seen where many mothers began to cry while speaking.

Activities of Daily Living↗
PubMed1994

P300 event-related potentials in epileptic children.

To evaluate the cognitive function of epileptic children, we examined P300 in 50 patients, 32 with idiopathic generalized epilepsy (IGE) and 18 with temporal lobe epilepsy (TLE), and 39 normal children. There were significant negative correlations between age and P300 latencies at Pz and Cz in normal controls. For data analysis, we used the age-corrected latency, which was calculated as the interval between the actual and predicted P300 latencies. The predicted latency was calculated with the regression equation as the relationship between P300 latency and age in normal controls. The age-corrected P300 latencies recorded from Pz and Cz were significantly longer in patients with IGE (41.5 +/- 13.1, 42.0 +/- 12.5) than in control subjects (0 +/- 7.5, 0 +/- 7.9). There were no significant differences in age-corrected P300 latencies between patients with TLE (21.2 +/- 17.6, 31.5 +/- 17.0) and controls, or IGE and TLE. Recently, it was considered that the mesencephalic reticular formation and thalamus may play major roles in the genesis of generalized epilepsy, so we speculate that dysfunction of these systems may contribute to the prolongation of P300 in children with idiopathic generalized epilepsy.

Adolescent↗
PubMed1994

Virtually unaltered permeability-surface area products imply little capillary recruitment in brain with hypoxia.

OBJECTIVE: To test the capillary recruitment hypothesis for the brain with control and hypoxic rats. METHODS: Local cerebral blood flow (LCBF) was sharply raised by respiring 10% O2 (hypoxia). LCBF as well as local influx rate constants (K1) and permeability-surface area (PS) products of 14C-antipyrine and 14C-3-O-methyl-D-glucose (30MG) were estimated for capillary systems in 44 brain areas. RESULTS: With this testing, an increase in PS product would be suggestive of capillary recruitment. In all brain areas, LCBF was increased by 30-90% by hypoxia. Hypoxia modestly raised the influx of antipyrine in brain but did not appreciably alter its PS products. With hypoxia, K1's and PS products of 30MG were significantly lowered (5-25%) throughout the brain, and the blood levels of glucose were sizeably raised. The latter increase would diminish the transfer of 30MG across the blood-brain barrier by the hexose transporter because of increased glucose competition. By applying a glucose-concentration correction to the data, the apparent PS product of 30MC for the hypoxic group became equal to that for the controls, which agrees with the antipyrine PS product results. CONCLUSIONS: Hypoxia, thus, leads to virtually no increase in PS products and no capillary recruitment in brain, and elevates LCBF mainly, perhaps exclusively, by raising the velocity of flow through already perfused capillaries.

3-O-Methylglucose↗
PubMed1994

Low-molecular-size allergens, LM-1s, in feces extract of Dermatophagoides farinae which elicit histamine release from washed blood cells of patients with bronchial asthma.

A significant activity to elicit histamine release was found in an ultrafilterable (Mr-cutoff < 10 kD) fraction of a mite feces extract from a spent mite medium. The activity was divided into two fractions (LM1 and LM2) on an Ultrogel AcA 54 column when monitored by histamine release assay using washed peripheral blood cells from mite-allergic patients. The larger-molecular-size antigen, LM1 was further separated into three allergenic fractions by consecutive chromatography on Sephadex G-50, GM-DEAE, and TSKgel ODS-120T. All the purified allergens, LM1s (LM1a, LM1b, and LM1c), which produced positive reactions in skin tests on allergic patients, were glycoproteins (molecular weight: 8 kD on SDS-PAGE; 12.5 kD on Gel filtration) with different carbohydrate contents and pI values ranging from 4 to 5 on an IEF plate. LM1s were cross-reactive with anti-Der f II but not with anti-Der f I. The reaction of LM1c to anti-Der f II serum was completely inhibited with the other antigens, while the reactions of LM1a and LM1b to the serum were partially inhibited with LM1c or the other antigens, respectively.

Allergens↗
PubMed1994

A low-molecular-size LM2 allergen in mite, Dermatophagoides farinae, extracts containing feces which elicits conjunctival reactions in patients with bronchial asthma.

A low-molecular-size antigen, LM2, which possesses a significant activity to elicit histamine release, was isolated from an ultrafilterable (Mr-cutoff < 10k) fraction of a mite extract containing feces by consecutive chromatography on Ultrogel AcA 54 and Sephadex G-25. The isolated antigen was still heterogeneous glycoproteins, giving a smeary band around pI 3-5 on an Ampholine PAG plate, with molecular weights of 6-8k and 4k on SDS-PAGE and Sephadex G-50 gel filtration, respectively. Chemical treatments of the antigen suggested that the epitope responsible for the elicitation of histamine release resided in the protein moiety. The antigen had activities to provoke conjunctival congestion and histamine release in mite-allergic patients, but not immunogenicity by itself. The antigen competitively inhibited the reactions of HM1, HM2, and HM3 fractions to corresponding antisera, but did not cross-react with anti-Der f I or anti-Der f II sera.

Allergens↗
PubMed1994

[Factors contributing to exercise-induced hypoxemia in patients with chronic lung diseases].

Arterial oxygen tension (PaO2) was found to decrease linealy during incremental exercise in patients with chronic lung diseases. The slopes of PaO2 during increasing workload (delta PaO2/delta VO2) in patients with COPD were closely and negatively correlated with diffusing capacity of the lung (DLco). In patients with IPF, the values of delta PaO2/delta VO2 were much higher, and were more strongly correlated with DLco than those in patients with COPD. Therefore, exercise-induced hypoxemia (EIH) was found to be related to three factors: PaO2 at rest, PaO2 slope predicted from %DLco, and exercise workload. The most important factor in EIH in patients with COPD was the decrease in PvO2 during exercise, which was caused by right heart failure and venous admixture. In patients with IPF, EIH was caused by abnormal O2 diffusion during exercise, decreased PvO2, and venous admixture. In conclusion, the factors contributing to EIH depend on the workload, so exercise testing is needed to decide on exercise therapy and O2 therapy in patients with chronic lung diseases.

Aged↗
PubMed1994

[Recent advances in the management of chest trauma].

Emergency care of chest trauma has progressed greatly over the past two decades. Factors contributing to this progress include changes in the system for providing emergency medical services; the development of imaging diagnostic tools such as ultrasonography, computed tomography, magnetic resonance imaging, and computerized dynamic stereo radiography; advances in respiratory and circulatory care: and the spread of sophisticated methods of surgical management such as emergency room thoracotomy and thoracoscopic surgery. The vast majority of patients with chest trauma can be managed nonoperatively, with tube thoracostomy, pain control, chest physiotherapy, and medication. It is not unusual for pain relief or a single chest tube to improve a patient's condition dramatically. Therefore, every physician should know how to manage patients with chest trauma and how to make critical decisions as quickly as possible.

Diagnostic Imaging↗