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H Shio

Publications and source records attributed to H Shio.

At least 37 records · Page 2Linked to original sources
PubMed1994

LTC4/LTB4 alterations in rat forebrain ischemia and reperfusion and effects of AA-861, CV-3988.

LTC4, which enhances vascular permeability and promotes tissue edema, and LTB4, which is a potent chemotactic and activating factor for leukocytes, were measured in rat brain after ischemia and several time periods of reperfusion. Forebrain ischemia was induced by 4-vessel occlusion. LTC4/LTB4 in the brain were measured by RIA. We also studied the effects of a 5-lipoxygenase inhibitor, AA-861 and a PAF antagonist, CV-3988 on LTC4/LTB4 concentrations. LTC4 in brain tissue increased during 30 min forebrain ischemia (p < 0.001). After reperfusion, LTC4 increased further, but at 15 min reperfusion LTC4 returned to the control level. Tissue levels of LTB4 in the brain increased during 30 min ischemia and remained high until 5 min after reperfusion (p < 0.01) returning at 15 min reperfusion to the control level. AA-861 inhibited elevation of LTC4/LTB4 in the reperfusion phase, but was not effective during ischemia. CV-3988 had a similar effect. LTC4 and LTB4 may be involved in the pathogenesis of ischemia brain edema and leukocyte infiltration. Further, PAF and LTs have many similarities of their pathophysiological properties, and may interact therefore in pathologic process.

Animals↗
PubMed1994

Hemichorea in hyperglycemia associated with increased blood flow in the contralateral striatum and thalamus.

We studied a patient with hyperglycemia who developed choreic involuntary movements in the right extremities using single photon emission computed tomography (SPECT) with 123I-N-isopropyl-p-iodoamphetamine. SPECT revealed an increased blood flow in the left striatum and thalamus. Through the control of blood glucose and the administration of haloperidol, the hemichorea was resolved, and the increased blood flow in the striatum and thalamus disappeared. These findings suggest that the increased blood flow, which probably indicates increased neuron activity in the striatum and thalamus, is an underlying pathophysiological state in hemichorea.

Aged↗
PubMed1994

Rheologic and pathophysiologic significance of red cell passage through narrow pores.

To elucidate the pathophysiologic significance of red blood cell (RBC) filterability, we measured RBC rheology with our own designed nickel mesh with 3-microns pores, smaller than the previously used 5-microns pores. Vertical and cylindrical pores with no pore coincidence were regularly distributed across the filter, the pore entrances of which showed a round and rather smooth transition to the pore inside. An advantage of the nickel mesh is the repeated use (at least 100 times) of the same filter possible after ultrasonic washing. A very low concentration of RBC, i.e., 3 x 10(4) cells per cubic millimeter (hematocrit value of approximately 0.3%), was sufficient for a typical test to examine RBC filterability. The filtration of the dilute RBC suspension was not influenced by contaminating or added leukocytes up to a leukocyte count of approximately seven cells per cubic millimeter; therefore, measurements can be performed using conventionally washed RBCs. This may be practically relevant to routine use, such as in a clinical laboratory. As compared with filtration through 5-micron pores, filtration through 3-micron pores was found to be very sensitive in detecting major determinants of RBC deformability, particularly, changes in viscoelastic properties of the cell membrane, surface area/volume ratio of the cell, perturbing effects of lysophosphatidylcholine, and osmolality of the medium. The 3-micron filtration method revealed a marked impairment in the filterability of Heinz body-containing RBCs from patients with unstable hemoglobin (Hb) disease (Hb Yokohama). Thus, 3-micron-filtration measurements may contribute to several subfields of hematology.

Cell Size↗
PubMed1992

Transfer of a dense granule protein of Plasmodium falciparum to the membrane of ring stages and isolation of dense granules.

A 14-kDa protein was localized to the dense granules of Plasmodium falciparum by immunoelectron microscopy with monoclonal antibody 1H1. The protein was present in dense granules in late-stage schizonts and free merozoites. After invasion, the protein was localized exclusively on the membrane of the newly invaded ring. The protein is referred to as RIMA, for ring membrane antigen. The 14-kDa protein was synthesized late in schizogony as determined by immunofluorescence microscopy and immunoblotting. At the late schizont stage it was distributed diffusely throughout the intracellular schizont. Only at the segmenter stage was the protein localized in defined spots that correspond to dense granules. Dense granules were isolated from schizont-infected erythrocytes by subcellular fractionation on a sucrose gradient. Fractions containing the 14-kDa protein were detected by immunoblotting with monoclonal antibody 1H1. The 14-kDa protein was first detected in vesicles at the late (8-nucleus) schizont stage. Mature dense granules sedimented with a peak density of 1.17 g/ml, which is similar to the density of rhoptries isolated by the same procedure.

Animals↗
PubMed1991

Peroxisomes in Saccharomyces cerevisiae: immunofluorescence analysis and import of catalase A into isolated peroxisomes.

To isolate peroxisomes from Saccharomyces cerevisiae of a quality sufficient for in vitro import studies, we optimized the conditions for cell growth and for cell fractionation. Stability of the isolated peroxisomes was monitored by catalase latency and sedimentability of marker enzymes. It was improved by (i) using cells that were shifted to oleic acid medium after growth to stationary phase in glucose precultures, (ii) shifting the pH from 7.2 to 6.0 during cell fractionation, and (iii) carrying out equilibrium density centrifugation with Nycodenz containing 0.25 M sucrose throughout the gradient. A concentrated peroxisomal fraction was used for in vitro import of catalase A. After 2 h of incubation, 62% of the catalase was associated with, and 16% was imported into, the organelle in a protease-resistant fashion. We introduced immunofluorescence microscopy for S. cerevisiae peroxisomes, using antibodies against thiolase, which allowed us to identify even the extremely small organelles in glucose-grown cells. Peroxisomes from media containing oleic acid were larger in size, were greater in number, and had a more intense fluorescence signal. The peroxisomes were located, sometimes in clusters, in the cell periphery, often immediately adjacent to the plasma membrane. Systematic immunofluorescence observations of glucose-grown S. cerevisiae demonstrated that all such cells contained at least one and usually several very small peroxisomes despite the glucose repression. This finding fits a central prediction of our model of peroxisome biogenesis: peroxisomes form by division of preexisting peroxisomes; therefore, every cell must have at least one peroxisome if additional organelles are to be induced in that cell.

Acyl-CoA Oxidase↗
PubMed1990

Further investigations of red cell deformability with nickel mesh.

Although the filtration method has been widely employed in red cell deformability studies, the structural irregularity of the pores of a Nuclepore polycarbonate membrane has always been a major problem. Anegawa, T. et al. (Clin. Hemorheol., 7, 1987) obtained a higher reproducibility with the filtration method using a newly designed thin metal film with pores engraved by the photofabrication technique. We further studied the pressure - flow rate relationship of red cell suspension employing this nickel mesh. The filtration of red cell suspensions through the nickel mesh was not influenced by leukocytes contamination or added leukocytes up to a leukocyte count of 250 cells/mm3 within an experimental limitation. On the other hand, the flow was greatly influenced by leukocytes contamination when the polycarbonate membrane was used. The nickel mesh was found to be useful in detecting major determinants of red cell deformability, such as cell geometry and internal cellular viscosity, and in detecting abnormalities of red cell deformability in a patient with microangiopathic hemolytic anemia. In conclusion, the present study clearly shows that the nickel mesh is preferable for investigating red cell deformability to the polycarbonate membrane from a quantitative point of view. This material should contribute to the physiologic and clinical investigation of red cell deformability.

Anemia, Hemolytic↗
PubMed1989

Electron spin resonance studies of erythrocyte membrane in spinocerebellar degeneration.

Erythrocyte membrane fluidity was examined by electron spin resonance spectra using nitroxide fatty acid spin labels in spinocerebellar degeneration (SCD). Subjects with SCD, motor neuron disease (MND) and controls did not differ in fluidity of the deep site (hydrophobic region) of the erythrocyte membrane. However, the fluidity of the shallow site (hydrophilic region) in the erythrocyte membrane was significantly less fluid in SCD than in controls and MND (outer hyperfine splitting of 5-nitroxide stearic acid: SCD 54.70 +/- 0.43 G, controls 53.57 +/- 0.41 G, MND 53.54 +/- 0.35 G, P less than 0.001). Serum HDL-cholesterol and membrane fluidity correlated significantly in controls, but not in SCD. A significant negative correlation between age and membrane fluidity was found in SCD, but not in controls. These data suggest that membrane abnormality exists in SCD and may be concerned with aging.

Adolescent↗
PubMed1989

The risk factors for ischemic heart disease in Tibetan highlanders.

The risk factors for ischemic heart disease (IHD) in 35 Tibetan highlanders were investigated and compared with those in 30 age- and sex-matched healthy Japanese controls. Although Tibetans had remarkably high hematocrit values, and a decrease of eicosapentaenoic acid in both serum total lipids and serum phospholipid (PL) possibly due to their diet, they were considered to have a low incidence of IHD from our door-to-door study. These positive risk factors are likely counteracted by other negative risk factors as follows; Tibetans rarely exhibited systolic hypertension, and had lower levels of serum cholesterol and serum apolipoprotein (apo) B, and apo B/apo A-I ratio. In addition, Tibetan highlanders showed a decreased level of palmitic acid and an increased level of linoleic acid in serum PL which may protect against atherosclerosis.

Altitude↗
PubMed1989

[A case of Burkitt's lymphoma with numb chin syndrome as the initial manifestation].

In 1963, Calverley and Mohnac reported four cases with sensory disturbance of the mental nerve region. They emphasized the symptomatological significance of that finding because of the underlying ominous diseases. The purpose of this paper is to emphasize the clinical importance of this symptom especially as the initial manifestation of the underlying malignant diseases. A 56-year-old Japanese female was seen in consultation because of complaints of the paresthesia over the distribution of the right mental nerve, diplopia and ptosis of the right side. The patient had been well until a hundred days prior to admission, when she noted numbness with pain of the right mental nerve region. This symptom was followed by ptosis of the right side and diplopia after five weeks. MRI-CT scan revealed an abnormally low intensity echo (in T1 weighted image) of the bone around sphenoid sinus and tumor of the cavernous sinus (in T2 weighted image) compressing the right internal carotid artery. The patient was transferred to this hospital 100 days after the occurrence of the initial symptom. Physical examination revealed neither superficial lymph node swelling nor buccal tumor. Abnormal findings were restricted to the cranial nerve regions such as diplopia, adduction disturbance, sluggish light reflex of the right side and hypesthesia on the right chin, lower lip and buccal mucous membrane. Other neurological findings were not significant. Laboratory findings showed elevated LDH (1,503 IU/L). Leucocyte cell count was 7,500/mm3 with almost normal composition. CSF was normal. A diagnosis of Burkitt's lymphoma stage IV was done by nasopharynx and bone marrow biopsies.(ABSTRACT TRUNCATED AT 250 WORDS)

Burkitt Lymphoma↗