Biomedical subjects

H Shibata

Publications and source records attributed to H Shibata.

At least 325 records · Page 18Linked to original sources

PubMed1995

Responses of plasma adrenocortical steroids to low dose ACTH in normal subjects.

OBJECTIVE: The standard ACTH test in clinical use employs a pharmacological dose of ACTH which assesses the maximum secretory capacity of the adrenal cortex. We have investigated the responses of plasma adrenocortical steroids including cortisol, aldosterone and dehydroepiandrosterone (DHEA) to physiological doses of ACTH (ACTH 1-24, tetracosactide, Cortrosyn) and determined the minimal dose which induces a response equivalent to that induced by a pharmacological dose of ACTH. DESIGN: Rapid ACTH tests at various physiological (0-1, 0.5, 1 and 5 micrograms) and standard pharmacological (250 micrograms) intravenous doses. SUBJECTS: Seven healthy normal volunteers. MEASUREMENTS: Plasma cortisol, aldosterone and DHEA were measured. Peak value and the increment from basal value were used as indices of responses. RESULTS: Each steroid responded to physiological doses of ACTH in a dose dependent manner. The minimum dose inducing an equivalent response to 250 micrograms ACTH was 0.5 micrograms for peak and incremental values in cortisol and DHEA, while that for aldosterone was 0.1 microgram. The time to peak for each steroid was delayed as the dose increased. Plasma aldosterone and DHEA peaked significantly earlier than plasma cortisol in 1-5 micrograms and 0.5-5-micrograms ACTH tests, respectively. CONCLUSIONS: These results suggest that the sensitivity of secretion to physiological doses of ACTH in descending order is aldosterone > DHEA = cortisol. When peak and incremental values are used, sufficient doses of ACTH are 0.1 microgram for plasma aldosterone and 0.5 microgram for plasma cortisol and DHEA in the rapid ACTH test.

Adrenal Cortex Hormones↗

PubMed1995

Simultaneous DNA typing of human platelet antigens 2, 3 and 4 by an allele-specific PCR method.

We developed an allele-specific polymerase chain reaction (ASPCR) method using originally designed primers to determine the genotype of the human platelet antigens (HPAs) 2, 3 and 4 in parallel. The results were compared with those obtained by PCR restriction fragment length polymorphism and the mixed passive hemagglutination test. Seventy-three individuals were tested and the ASPCR results were in good agreement with those determined by the other two methods. This method enables the genotyping of HPA-2, -3 and -4 in parallel without the use of platelets, platelet-specific alloantibodies or restriction enzymes.

Alleles↗

PubMed1995

The use of PCR in detecting toxoplasma parasites in the blood and brains of mice experimentally infected with Toxoplasma gondii.

Polymerase chain reaction (PCR) has been extensively used for diagnosis recently because of its very high sensitivity and specificity. We studied the applicability of PCR to the early diagnosis of toxoplasmosis in a murine model orally infected with Toxoplasma gondii (S-273). PCR was performed using EH24 and HE27 primers synthesized by the phosphoramidite method. Mice blood and brains collected on various post infection days (PID) were analysed by PCR (35 cycles). A portion of the brain tissue from each mouse was examined microscopically for the presence of parasite cysts. Blood and brain PCR were positive on the 9th and 12th day post-infection (DPI). Toxoplasma cysts in brain tissue appeared only on the 18th PID. The results showed that Toxoplasma parasites can be detected earlier in the blood than in the brain during primary infection, indicating that blood PCR is the more useful procedure.

Animals↗

PubMed1995

Attenuation of glycogenolytic action of activin A in intact rat liver.

Activin A stimulates glucose production by causing glycogenolysis in isolated hepatocytes. To determine the physiological significance of this effect, we examined the effect of activin A on glucose production in the perfused liver. Unlike the effect in isolated cells, activin A did not enhance glucose production nor did it cause radiocalcium efflux in the perfused liver. There was no effect of activin A in the liver perfused in the opposite direction. Although activin A did not promote glucose production, it was recovered from the hepatic vein in a bioactive form. When liver perfusion was performed in partially hepatectomized rats, activin A increased radiocalcium efflux. In isolated hepatocytes, activin A increased inositol phosphates, and the effect of activin A was attenuated by the plasma membrane fraction of hepatocytes. The inhibitory effect of the plasma membrane was abolished by digestion of the membrane with trypsin. These results indicate that the effect of activin A on glucose production is attenuated in the intact liver and that a protein factor(s) in plasma membrane may be involved in the inhibition.

Activins↗

PubMed1995

Modulation of muscle protein metabolism in disseminated intravascular coagulation.

Muscle protein degradation and intracellular protease activities were investigated in disseminated intravascular coagulation (DIC), which is frequently associated with severe catabolic states such as sepsis and multiple organ failure. DIC was introduced in rats by repeated intravenous thrombin injections. Saline was injected in control rats. In the 28 rats (14 with DIC and 14 controls), the bilateral soleus (SOL) muscles were incubated in an oxygenated medium without cycloheximide (CH) to determine the release of tyrosine (Tyr) into the incubated medium. From 24 rats (12 with DIC and 12 controls), the SOL and extensor digitorum longus (EDL) muscles were harvested to measure the activities of proteasome and of cathepsins L and B. The contralateral muscles were incubated in a medium with 0.5 mM CH to determine the release of Tyr and 3-methylhistidine (3-MH). The release of Tyr without CH (net proteolysis) from SOL muscles with DIC was greater than in controls (218 +/- 83.3 vs. 145 +/- 47.7 pmol/mg/h. However, the release of Tyr and 3-MH with CH (total proteolysis) and the activities of proteasome and cathepsins in DIC were nearly the same as those in controls. In both DIC and control rats, the total release of Tyr and proteasome activity were greater in SOL than in EDL muscles. These results suggest that reutilization of Tyr, reflecting protein synthesis, is suppressed in DIC and that the red slow muscle is more active in nonfibrillar proteolysis than the white fast muscle.

Animals↗

PubMed1995

Comparative mapping of the imprinted U2afbpL gene on mouse chromosome 11 and human chromosome 5.

The genetic map location of the recently discovered imprinted gene U2afbpL has been verified and refined in several mouse crosses. RI strain analysis had previously shown that the gene is located on mouse chromosome 11. This assignment has been verified using interspecific backcrosses. Moreover, the location of the gene relative to a fixed order of markers in the proximal region of mouse chromosome 11 has been established. The location of the gene on mouse chromosome 11 corresponds to a homologous linkage group that is conserved on human chromosome 5q. The location of the human homologue has been determined using both somatic cell hybrid genetic analysis and fluorescence in situ hybridization. These analyses have mapped the human locus U2AFBPL to human chromosome 5q23-->q31.

Animals↗

PubMed1995

Gene expression of angiotensin II receptor in blood cells of Cushing's syndrome.

The relation between serum cortisol, plasma renin activity, angiotensin II (Ang II), or aldosterone levels and peripheral blood cell (mononuclear leukocytes and platelets) angiotensin II type 1A (AT1A) and 1B (AT1B) receptor mRNA levels was examined in both patients with Cushing's syndrome (seven patients with Cushing's syndrome due to unilateral adrenal cortical adenoma) and control subjects (seven normotensive patients with renal cell carcinoma). Blood was collected from each participant for estimation of plasma renin activity and plasma angiotensin II, aldosterone, and cortisol concentrations and for isolation of mononuclear leukocytes and platelets, which were then used to measure AT1A and AT1B receptor mRNA levels before and after adrenalectomy with the use of reverse transcription-polymerase chain reaction. In patients with Cushing's syndrome, both mononuclear leukocyte and platelet AT1A mRNA levels, which were elevated, were reduced after removal of the adrenal tumors, whereas AT1B receptor mRNA levels of both types of blood cells did not significantly change after adrenalectomy. In contrast, in control subjects, both AT1A and AT1B receptor mRNA levels did not significantly change after unilateral adrenalectomy and nephrectomy. In the adrenal tumors of patients with Cushing's syndrome, gene expression of AT1A receptor was decreased compared with that from adrenals of control subjects. AT1A receptors of the platelets were shown to be upregulated in a manner similar to those of mononuclear leukocytes in patients with Cushing's syndrome. These results suggest that cortisol excess is an important factor upregulating AT1A receptor mRNA levels in human blood cells.

Adenoma↗

PubMed1995

Modulation of angiotensin II type 1 receptor mRNA expression in human blood cells: comparison of platelets and mononuclear leucocytes.

The objective of the present study was to quantify the expression of angiotensin II type 1 (AT1) receptor transcripts in human blood cells--platelets and mononuclear leukocytes--from 10 normal healthy volunteers during the alterations in the renin-angiotensin system. A quantitative assay employing reverse transcription-polymerase chain reaction (RT-PCR) was utilized. Oral administration of furosemide, 40 mg for 2 days, under mild salt restriction (50 mEq NaCl/day) for 6 days stimulated the renin-angiotensin system resulting in significant increases in plasma renin activity (PRA) (1.84 +/- 0.12 vs. 1.05 +/- 0.17 ng/l/s; P < 0.01), plasma angiotensin II concentration, and plasma aldosterone concentration (PAC). The ratio of AT1 receptor mRNA to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA expression in mononuclear leucocytes was significantly (P < 0.05) increased from the basal level (0.49 +/- 0.05 vs. 0.29 +/- 0.03) (P < 0.01), while in platelets these changes were opposite (0.11 +/- 0.05 vs. 0.25 +/- 0.05) (P < 0.01). Compared to these significant changes, salt loading (200 mEq NaCl/day) for 6 days decreased PRA(0.49 +/- 0.10 vs. 1.05 +/- 0.17 ng/l/s; P < 0.01) and induced the opposite changes in the ratio of AT1 receptor/GAPDH mRNA. These data suggest that AT1 receptors in human blood cells may be of two different types--platelets and mononuclear leucocytes.

Adult↗

PubMed1995

[Ictal electroencephalographic recordings of patients with seizure].

We analyzed the ictal electroencephalographies (EEGs) in 75 seizures of 73 patients. Eighty percent of the patients were below the age of 20. The seizures consisted of 35 generalized seizures, 24 partial seizures and 16 pseudoseizures. The ictal EEG of true seizures showed changes with a spike in 23 cases, and change without spike (eg. rhythmic activity, desynchronization) in 32 cases. Four ictal records could not be evaluated due to artifacts. Because half of the patients with pseudoseizures also had epilepsy, their ictal EEG examinations were very useful. The ictal EEG examination could be performed successfully on 96% of the patients with a seizure frequency of more than six a day, 52% of them with one to five seizures a day and eleven percent of them with less than one seizure a day. Seventy-five percent of ictal EEG recordings were performed when the patient was awake. The cassette of electrodes, originally made in our department, was very useful in recording the ictal EEG of children when they were awake.

Child, Preschool↗

PubMed1995

[Clinicopathological studies of anti-HCV P1P4 core antibody].

Anti-P1P4 core antibody, derived from a Japanese hepatitis C virus clone, was evaluated clinicopathologically in serum samples from 40 blood donors positive for anti-HCV antibody by 2nd generation assay and in 37 patients with HCV chronic hepatitis treated with interferon. The presence of anti-P1P4 antibody was highly correlated with the presence of HCV-RNA in the blood donors. In the patients with chronic hepatitis, more than a 50% reduction in P1P4 antibody titer after interferon therapy suggested the disappearance of HCV-RNA from the blood. Thus, anti-P1P4 antibody was useful in evaluating the virological effects of interferon therapy. However, clinically and pathologically, the titer of P1P4 antibody did not indicate the grade of liver inflammation.

Hepacivirus↗

PubMed1995

[Pharmacological and biochemical investigation of intracavital fluorinated pyrimidine chemotherapy].

We investigated the biochemical and molecular pharmacological parameters of fluorinated pyrimidines using malignant cells in pleural effusion or ascites from patients with malignant disease both before and after fluorinated pyrimidine chemotherapy, either systemically or intravesically. In four out of fifteen cancer patients, we could analyze the alteration of thymidylate synthase (TS) catalytic activity both before and after the treatment, showing that there was a decrease ranging 28% through 96.9%. We also analyzed a level of TS messenger RNA and TS protein using molecular biotechniques. None of these mutual correlations has so far been demonstrated, indicating that the data were analyzed through samples from patients not responding to the fluorinated pyrimidines. In a responding patient with advanced breast cancer, pre-treatment total TS protein was 130 fmol/mg and the TS activity was 3.27 pmol/mg/min. After intrapleural instillation of a combination of 5-FU 250 mg and leucovorin 3 mg, the total amount and the catalytic activity of TS could be measured. On the 11th day of treatment, the TS protein level decreased to 26 fmol/mg and the TS catalytic activity also decreased to 0.1 pmol/mg/min resulting in a TS inhibition rate of 92.3 percent. On the 17th day, the patient's malignant pleural effusion disappeared almost completely, suggesting that substantial TS inhibition may reflect the clinical evidence. This particular data showed that it would be predictable for clinical outcome to evaluate these parameters before and after fluorinated pyrimidine chemotherapy. Further study is warranted to evaluate the exact role of analyzing these parameters in clinical practice.

Aged↗

PubMed1995

[Cholinesterase].

Since the chromatographic separation of cholinesterase (ChE) by Malström in 1956 many investigator studied ChE isozyme, Harris divided five spots by two dimensional paper electrophoresis and starchgel electrophoresis, and referred as C1 C2 C3 C4. Clinically, Juul separated ChE 12 bands by polyacrylamidegel electrophoresis. We separated ChE as five bands using polyacrylamidegel electrophoresis, revealing fusion and deformity of the band. Takahashi et al reported separation of band using acetyl and butyrylthiocholine as substrate. They found abnormal band in liver cirrhosis, however they have thought it acetyl cholinesterase. Hada et al revealed a defect of band II in liver cirrhosis. They investigated ChE isozyme using affinity electrophoresis with Concanavalin A (Con A) and wheat germ agglutinin (WGA). They found disappearance of band 2, Con A and WGA containing agarose gel electrophoresis seem to be useful method in differentiating liver cirrhosis from chronic hepatitis. The number of isozyme fraction exhibited a species related variations in laboratory animals. Rats, hamsters guinea pigs, rabbits, dogs, monkeys, pigs, horses and quails have 4, 3, 4, 3-5, 3, 3, 4 and 3 isozyme bands, respectively.

Animals↗

PubMed1995

[Appropriateness and limitations of bone mineral measurements by DXA (dual energy x-ray absorptiometry) in the elderly--comparison with x-ray findings].

A group of 674 (266 males and 410 females) elderly living in a rural community of Nangai Village, Akita Prefecture, were subjects of bone mineral measurements in the lumbar spine and three areas of proximal femur (femoral neck; FN, trochanter; TR and Ward's triangle; WD). Measurement was by dual energy x-ray absorptiometry (DXA) set in a mobile van during mass health examination. The purpose of this study was to verify the appropriateness and imitations in the bone mineral measurements by DXA in elderly who have other aging related abnormal calcifications such as osteophytosis in the lumbar spine and calcification of the abdominal aorta, all of which may have an influence on the 'true' value of bone mineral density (BMD) particularly in the lumbar region. The results were as follows: 1) Subjects who were not capable of being measured by DXA tended to be older and reported experiencing pain and who scored low in TMIG index of competence compared to measurable subjects. 2) BMD of 2nd-4th lumbar spine with antero-posterior projection (AP) did not show simple age-declines that are seen in younger generations. In contrast, BMDs of proximal femur show linear aging declines. 3) Analysis of the association between BMDs and osteophytosis by spondylosis deformans in the lumbar spine and calcification of the abdominal aorta in front of the lumbar spine showed that AP-BMD had a strong correlation with the grade of both spinal osteophytosis and aortic calcification. On the other hand, BMDs of proximal femur showed no significant associations with these abnormal calcifications. 4) In this context, in order to evaluate the 'true' BMD in the elderly, BMDs in the proximal femur are a more appropriate indicator than AP-BMD which may be easily contaminated by other aging-related calcification in and around the lumbar region.

Absorptiometry, Photon↗

PubMed1995

[Psychosocial determinants of changes in activities of daily living and depressive status among stroke patients at home].

Using a longitudinal study of 79 stroke patients, factors that are predictive of change in activities of daily living (ADL) and depressive status over three and a half-year period were examined. Social activities, health behavior, and depressive status were entered as predictive variables. Those who participated in community activities, had significantly less decline in ADL than those who did not, and those who reported a greater variety of leisure activities had less decline in depressive status during the follow-up period.

Activities of Daily Living↗

PubMed1995

[Relationship of physical condition and functional capacity to depressive status in person aged 75 years].

The purpose of the present study is to examine cross-sectionally and longitudinally the relationship of physical conditions and functional capacity to depressive status in the elderly. Subjects comprised 308 men and women aged 75 years and over living at home in a rural community. Geriatric Depression Scale (GDS) was employed to assess depressive status, and physical conditions and functional capacity were simultaneously investigated. The results obtained were as follows; 1. There was no significant difference in GDS score by age or sex. 2. Cross-sectionally, the depressive status was significantly associated with weakened grip strength and poor locomotion in men, and it was associated with experience of falls, poor chewing ability, and low levels in high functional capacity as measured by the TMIG Index of Competence. 3. Longitudinally over a 2 year period, bereavement, decline of locomotion, and persistent anxiety about physical conditions significantly influenced aggravation of the depressive status in men. In women, high systolic blood pressure and visual and/or hearing impairment influenced the aggravation. Decline in functional capacity as measured by the TMIG Index of Competence appeared to influence the aggravation in both men and women.

Aged↗

PubMed1995

[Rapid cytology].

The indications for and limitations of rapid cytology were discussed, and intraoperative cytology in combination with frozen section histology was reviewed. During the past 14 years, intraoperative cytology and frozen section histology were simultaneously performed in 1,987 cases of various diseases and organs. A discrepancy between the cytologic and the frozen section diagnoses was noted in 39 (2.0%) instances, and the combined use of cytology and histology was concluded to be useful for correct intraoperative diagnosis owing to their supplementary effect. A rapid preparation and staining technique for intraoperative cytology was described.

Clinical Laboratory Techniques↗

PubMed1995

[Effect of mao-bushi-saishin-to (MBST), a formula of Chinese medicines, on 48 hr homologous passive cutaneous anaphylaxis in rats].

We studied the effect of oral administration of the extracts from MBST and its component chinese plants, and 1-ephedrine on 48 hr homologous passive cutaneous anaphylaxis (PCA), and histamine- or serotonin-induced skin reaction in rats. Administration (100-1,000 mg/kg) of MBST 1 hr before antigen challenge dose-dependently inhibited PCA. Skin reaction induced by histamine was also inhibited by this formula at 1,000 mg/kg 1 hr prior to the provocation in some degree. The inhibitory component of MBST of PCA was found to be Mao. Further examinations revealed that 1-ephedrine, which is contained in Mao in a large amount, did not substantially inhibit histamine- or serotonin-induced skin reaction. These results indicate that MBST has a significantly inhibitory activity on PCA, to which 1-ephedrine from Mao in the formula almost totally contributes, through the inhibition of chemical mediator release. Since MBST showed some inhibition of histamine-induced skin reaction, on which 1-ephedrine did not affect, it is suggested that some ingredient of MBST responsible for inhibition of PCA may be involved in addition to 1-ephedrine.

Animals↗

PubMed1995

[Effects of mao-bushi-saishin-to (MBST) on experimental allergic models in rats].

Effects of oral administration of MBST on 48 hr homologous passive cutaneous anaphylaxis (PCA) and allergic rhinitis in rats were examined. Administration of MBST (1,000 mg/kg/day) for 5 consecutive days with the final dosing at 1 day before antigen challenge did not effect on PCA. However, the reaction was significantly inhibited when the drug (1,000 mg/kg) was singly given 1 hr before antigen challenge. The drug (1,000 mg/kg, 1 hr prior to antigen challenge) tended to reduce the dye leakage into nasal cavities by antigen, while it did not affect on the anaphylactic histamine release into the cavities. The component of the chinese plants in the formula inhibiting the dye leakage was found to be Mao. However, l-ephedrine and d-pseudoephedrine, which are contained in Mao in a large amount, did not contribute to the inhibiting effect on dye leakage. These results suggest that MBST may be therapeutically effective for atopic disease including rhinitis, through the mechanism other than the inhibition of histamine release.

Animals↗