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Y Kasahara

Publications and source records attributed to Y Kasahara.

At least 19 recordsLinked to original sources
PubMed1996

Re-evaluation of chromosomal aberration induction on nine mouse lymphoma assay "unique positive' NTP carcinogens.

In a collaborative study organized under the JEMS MMS, nine mouse lymphoma assay (MLA) "unique positive' NTP rodent carcinogens were re-evaluated by an in vitro chromosomal aberration assay using Chinese hamster lung fibroblast cells (CHL/IU). Six of nine chemicals induced chromosomal aberrations; bromodichloromethane, chlorendic acid and isophorone induced structural aberrations, and chlorodibromomethane, pentachloroethane and 1,1,1,2-tetrachloroethane induced numerical aberrations (polyploidy). These six chemicals, therefore, are not uniquely positive in the MLA. The difference between the NTP results and ours might be due to the use of different cell lines and protocols, and in some cases, to different interpretations of polyploidy. The remaining three chemicals, benzyl acetate, cinnamyl anthranilate and trichloroethylene, were negative in this study.

Animals↗
PubMed1996

Expression of L-selectin (CD62L) discriminates Th1- and Th2-like cytokine-producing memory CD4+ T cells.

Human memory (CD45RO+) CD4+ T cells can be distinguished into two subpopulations on the basis of expression of the lymph node homing receptor, L-selectin (CD62L). In a prior study we showed that human L-selectin-positive memory T-helper (Th) cells promote the maturation of IgG- and IgA-producing cells by naive B cells. To further elucidate the contribution of memory CD4+ T cells to B-cell differentiation, human memory CD4+ T cells with or without L-selectin expression were evaluated for production of cytokines that participate in regulation of immunoglobulin production. It was found that L-selectin-positive human memory CD4+ T cells produce mainly interleukin (IL)-4 and IL-5, whereas L-selectin-negative CD4+ T cells produce mainly interferon-gamma (IFN-gamma). This profile of cytokine expression coincides with the profile that distinguishes Th1 and Th2 subsets. In contrast to the murine system, IL-10 production was similarly contributed by human L-selectin-positive and -negative memory CD4+ T-cell subpopulations. These results suggest that the human L-selectin-negative and -positive subpopulations of human memory CD4+ T cells contain Th1-like and Th2-like cytokine-producing cells, respectively.

Adult↗
PubMed1996

The test-retest reliability of the inventory to diagnose depression, lifetime version.

The test-retest reliability of the Inventory to Diagnose Depression, Lifetime Version (IDDL) was investigated, based on 57 first-degree relatives of probands with major depression. The subjects were first interviewed using the SCID, and then the IDDL was administered to them twice at a 1-month interval. The chance-corrected agreement in diagnosing a lifetime history of DSM-III-R major depression was high between the 2 trials of the IDDL (kappa = 0.77), and between the SCID and each of the 2 IDDL trials (kappa = 0.75 for the 1 trial, and 0.68 for the 2nd trial). The positiveness on all items except "increased appetite' and "weight gain' was also highly concordant between the 2 trials. These results strongly suggest that time-stable data with sufficient validity for diagnosing a lifetime history of depression can be given by using the IDDL.

Adult↗
PubMed1996

Avascular necrosis and the Pavlik harness. The incidence of avascular necrosis in three types of congenital dislocation of the hip as classified by ultrasound.

We analysed the incidence of avascular necrosis in 101 hips of 90 infants with congenital dislocation treated with Pavlik harness and followed up for more than one year. Using ultrasonography in the flexed-abducted position the hips were classified as type A when the femora head was displaced posteriorly, but within the socket and making contact with the posterior inner wall of the acetabulum; type B when it was in contact with the posterior margin of the acetabulum, with its centre at this level or anterior to it; and type C when it was displaced out of the socket, with its centre posterior to the posterior rim of the acetabulum. Eighty-seven hips were reduced by the harness (86%), and seven of these developed avascular necrosis (8%). All 69 hips with type-A dislocation were reduced and only one (1.4%) showed slight avascular necrosis. Eighteen (78.3%) of 23 hips with type-B dislocation were reduced, and six developed avascular necrosis (33.3%). In one hip, the femoral head was severely damaged. None of the nine hips with type-C dislocation was reduced in the harness. We concluded that the Pavlik harness is indicated for type-A but not for type-B or type-C dislocations.

Contraindications↗
PubMed1996

[Effects of thromboxane A2 on chronic hypoxic pulmonary hypertension in the rat].

Chronic hypoxia (10% O2 for 2-3 weeks) causes pulmonary hypertension and vascular remodeling in the rat. To study the role of thromboxase A2 in chronic hypoxic pulmonary hypertension, the hemodynamic effects of intravenous administration of a thromboxane analogue (STA2) were measured in chronic hypoxic (H) and normoxic (N) Sprague-Dawley rats. During anesthesia baseline pulmonary arterial pressure (PAP) was higher in H rats (34.6 +/- 1.0 mmHg) than in N rats (18.4 +/- 1.2 mmHg). Intravenous STA2 (0.3 microgram) acutely increased pulmonary artery pressure by 74% +/- 11% (25 +/- 4 mmHg) in H rats and by 47% +/- 2% (9 +/- 1 mmHg) in N rats, which indicates that both the absolute and relative acute pulmonary vasoconstriction caused by STA2 were greater in H rats. The changes in systemic arterial pressure caused by STA2 were smaller than the changes in pulmonary arterial pressure both in H rats (11% +/- 3%) and in N rats (17% +/- 3%). Lungs were isolated and perfused with saline, and the vasoconstrictive response to 0.05 microgram of STA2 in lungs (14.5 +/- 2.4 mmHg) from H rats was greater than the response to 0.1 microgram of STA2 (5.6 +/- 1.3 mmHg) in lungs from N rats. To examine whether blockade of calcium channels could suppress the vasoconstrictor response to STA2, the effects of the calcium channel blocker nicardipine hydrochloride on vasoconstriction caused by STA2 were measured in H and N rats. In vivo, the blockade of calcium channels suppressed the increase in pulmonary artery pressure caused by STA2. This suppression was greater in H rats (56% +/- 11%) than in N rats (25% +/- 4%). Similar results were obtained with isolated perfused lungs. Blockade of calcium channels suppressed the vasoconstriction caused by STA2 and this suppression was greater in H rats than in N rats. The finding that thromboxane A2 induced greater vasoconstriction in H rats than in N rats indicates that thromboxane A2 may play an important role in pulmonary hypertension, and suggests that blockade thromboxane A2 may benefit some patients with primary and secondary pulmonary hypertension. Furthermore, the finding that suppression of thromboxane-induced vasoconstriction by blockade of calcium channels was greater in H rats than in N rats indicates that such treatment may also benefit some patients.

Animals↗
PubMed1996

[Assessment by flow cytometric method of IgE-binding state of basophils in allergic disorders].

Basophils, as well as mast cells, express Fc epsilon RI on the surface. It is known that activation of basophils and mast cells leads to induction of chronic allergic inflammation. In this study, levels of IgE bound to the surface of peripheral blood basophils were measured using a flowcytometry, and their clinical relevance was evaluated. Peripheral whole blood samples were stained with FITC-conjugated anti-IgE. The fluorescence intensity of the FITC-positive cells within mononuclear cell region was determined. Basophil-bound IgE levels increased along with age and reached invariably high levels of adults. The levels of basophil-bound IgE were higher among allergics than normal controls, in early infancy. In addition, many of the infants with repeated wheezing episodes also exhibited high levels of it. These findings suggest that early exposure of predisposed infants to antigens leads to early sensitization of circulating basophils. Basophil-bound IgE levels correlated well with serum IgE concentration, but they remained constant when IgE concentrations exceeded 300 ng/ml, suggesting that IgE-binding capacity of basophils become saturated at this IgE level. In conclusion, it is shown that flowcytometric measurement of basophil-bound IgE provides a useful method of analyzing this rare cell population within the peripheral circulation, and it serves as a critical parameter to evaluate the allergic inflammation in vivo.

Adolescent↗
PubMed1995

Colorimetrical rate assay for urinary dipeptidyl peptidase IV (DPPIV) activity using a new substrate.

We synthesized a new substrate glycyl-L-proline 3,5-dibromo-4-hydroxyanilide (Gly-Pro-DBAP), for dipeptidyl peptidase IV (DPPIV). Its hydrolysis by DPPIV resulted in the formation of a chromophore, 2,6-dibromophenol-indo-p-xylenol, and its maximal absorption wavelength (600 nm) was longer than that of p-nitroaniline (415 nm) released from conventional substrate, glycyl-L-proline p-nitroanilide (Gly-Pro-pNA). We also established the rate assay for urinary DPPIV activity using Gly-Pro-DBAP. The optimum pH was between 8.5 and 9.0. The apparent Km was 1.1 mmol/1. The detectable range was 2.5-350 U/l. No changes in blank values occurred throughout the enzyme reaction in the optimum pH. Its value was also much lower than Gly-Pro-pNA. CVs for within-run and between-run were 1.1% (n = 10) and 3.0% (n = 10), respectively. Among tested peptidases, only DPPIV could hydrolyze Gly-Pro-DBAP. Among the protease inhibitors, only two, diprotin-A and phenylmethylsulfonyl fluoride (PMSA), could inhibit DPPIV activity. The present method did not interfere with urinary ingredients such as hemoglobin. The correlation between the present (y) and conventional (x) methods is presented by the equation y = 1.121x + 0.096 (r = 0.993). Thus the present method provides practical advantages over the conventional method for routine laboratory use.

Anilides↗
PubMed1995

Clinicopathologic studies of immunologic fecal occult blood test for colorectal cancer.

In our hospital, 83 patients with colorectal cancer underwent the immunologic fecal occult blood test (IFOBT). The positive rate for IFOBT in all patients was 87%. Colon cancers more proximal than the transverse colon were 100% positive. Carcinomas of the ulcerative type showed a significantly higher positive rate than those of the non-ulcerative type (94% vs 73%). Carcinomas penetrating the muscularis or beyond showed a significantly higher positive rate, of 96% (52/54 cases) compared to carcinomas confined to the mucosa or submucosa, which gave positive rates of 64% and 60%, respectively. In the investigation of the 7 patients with colorectal cancer who showed negative results on the IFOBT, IFOBT had been performed only once in of these patients. Accordingly, it was considered necessary to perform IFOBT more than once. The cancers in 5 of these 7 patients were found to be carcinomas confined to the mucosa. This result suggests the advisability of annual IFOBTs. It is also considered necessary to manage patients who show undefinable but possibly positive (+/-) results with caution.

Carcinoma↗
PubMed1995

Somatic cell mutation frequency at the HPRT, T-cell antigen receptor and glycophorin A loci in Cockayne syndrome.

Skin fibroblasts of patients with Cockayne syndrome (CS) are hypersensitive to the lethal or mutagenic effect of ultraviolet light, which may cause genetic instability. Up to now, however, no systematic study of in vivo somatic cell mutation in CS cells has been reported. This article describes our investigation of the mutation frequencies (Mfs) at three different loci, i.e. hypoxanthine-guanine phosphoribosyl transferase (HPRT), T-cell antigen receptor (TCR) and glycophorin A (GPA), in six patients with CS. Mfs at the HPRT and TCR loci were found to be within the normal range as determined in age-matched controls. In the GPA locus of two patients, there was a slight increase, but it was much smaller than that reported in other DNA repair deficient syndromes. The frequency of spontaneous HPRT mutation in Epstein-Barr virus transformed B-lymphoblastoid cells derived from CS patients was similar to that in cells from normal children. The molecular characterization of the representative HPRT mutant T cell clones from CS patients did not show any structural alterations. These results may explain, at least in part, why CS is not associated with predisposition to cancer.

Adolescent↗
PubMed1995

Immunoblot analysis of cellular expression of Bcl-2 family proteins, Bcl-2, Bax, Bcl-X and Mcl-1, in human peripheral blood and lymphoid tissues.

The ability of Bcl-2 to inhibit apoptotic cell death is well established. Several homologues of the bcl-2 gene, such as bax, bcl-x or mcl-1, have recently been identified. Like Bcl-2, both Bcl-XL and Mcl-1 appear to function as repressors of apoptotic cell death, whereas Bax facilitates it, indicating possible interactions among them in the control of cellular survival. To investigate the in vivo role of expression of bcl-2 gene family products, immunoblot analysis using corresponding specific antisera was performed for peripheral blood cells and some lymphoid tissues in humans. We demonstrated that all Bcl-2 family proteins were expressed at various levels in hematolymphoid cell subpopulations isolated from peripheral blood, tonsil, spleen and thymus. Lymphoid expression of Bcl-2 family proteins tended to increase following activation, but declined with time in culture. Loss of Bcl-2 in cultured lymphoid cells was especially marked. Sole expression of Bax, but not other members of the Bcl-2 family, was observed on neutrophils, seemingly reflecting their shortest life-span among blood leukocytes. The results support the notion that a balance of expression of Bcl-2 family proteins may regulate the life and death of hematolymphoid cells at different stages of cell differentiation and activation.

Acute Disease↗
PubMed1995

Determination of a 17,484 bp nucleotide sequence around the 39 degrees region of the Bacillus subtilis chromosome and similarity analysis of the products of putative ORFs.

We have determined a 17,484 bp nucleotide sequence around the 39 degrees region, located about 480 kb downstream from the zero position of the Bacillus subtilis chromosome physical map. Among the 17 putative ORFs identified, orf1 and orf2 seem to correspond to mtlA and mtlB, encoding mannitol-specific phosphotransferase enzyme II and mannitol-1-phosphate dehydrogenase, respectively. orf4 seems to be another signal peptidase I gene (sipS) of B. subtilis. The putative products of six ORFs were similar to known proteins in data banks, namely a hypothetical 29.7 kDa protein of Escherichia coli (Orf7), a lactam utilization protein (Orf8), the urea amidolyase of yeast (Orf12), the IcIR regulatory protein for aceAB of Salmonella typhimurium (Orf13), penicillin-binding protein 2 (Orf16) and aryl-alcohol dehydrogenase (Orf17). The amino acid sequence of Orf3 showed 34% identity with that of LeuC of B. subtilis, though they seem to be functionally different. The remaining seven ORFs did not show similarity to any known proteins.

Amino Acid Sequence↗
PubMed1995

Relationship between the melancholic type of personality (Typus melancholicus) and DSM-III-R personality disorders in patients with major depression.

The relationship between the melancholic type of personality (TM) and DSM-III-R personality disorders (PD) in a sample of 96 outpatients with major depression was investigated using a series of multivariate analyses. The results showed that the personality features of TM were quite different from those of any DSM-III-R PD, including obsessive-compulsive PD, and gave only partial support to the DSM-III-R classification of PD into three clusters. It is suggested that if the personality description of TM be included in the Axis II of DSM-III-R, the description of the Axis could have a wider range of personality features and could be more useful for the clinical praxis and research of depressive patients.

Adult↗
PubMed1995

Symptoms of psychoses. A factor-analytic study.

BACKGROUND: The literature on the statistical analysis of symptoms of psychoses was limited to positive and negative symptoms in schizophrenia. The present study explored the relationship between positive and negative symptoms as well as affective symptoms in a wider category of psychotic disorders. METHOD: The symptoms of 584 psychiatric patients, consecutively admitted to any of the 95 mental hospitals in Japan, were studied. They manifested at least one of the following: (a) delusions, (b) hallucinations, (c) formal thought disorder, (d) catatonic symptoms, or (e) negative (defect) symptoms. RESULTS: Factor analysis yielded five factors interpretable as (a) manic symptoms, (b) depressive symptoms, (c) negative (defect) symptoms and formal thought disorders, (d) positive (psychotic) symptoms, and (e) catatonic symptoms. CONCLUSION: These results suggest that although major symptoms seen among psychotic patients can be categorised into positive, negative, manic, and depressive groups, corresponding to current knowledge of phenomenology, catatonic symptoms constitute a discrete syndrome, while formal thought disorders merge into the negative syndrome.

Adolescent↗
PubMed1995

[Effects of beraprost sodium (a PGI2 derivative) on chronic hypoxic pulmonary hypertension in the rat].

To determine whether beraprost sodium (beraprost) can cause pulmonary vasodilation in chronic hypoxic pulmonary hypertension, we measured the hemodynamic effects of intravenous beraprost, a stable and orally active agent with a PGI2-like structure, in chronic hypoxic (H) and normoxic (N) rats. During anesthesia baseline pulmonary artery pressure (PAP) was 32.0 +/- 1.0 in H rats and 18.0 +/- 0.4 mmHg in N rats. Intravenous beraprost (20 micrograms/kg) elicited acute pulmonary vasodilation by 17.7 +/- 4.6% (5.6 +/- 1.4 mmHg) in H rats and by 16.8 +/- 2.1% (3.0 +/- 0.6 mmHg) in N rats, which indicates that the relative degree of acute pulmonary vasodilation caused by beraprost was similar in H and N rats. Thirty minutes after the drug was injected, PAP had not returned to baseline levels in either H or N rats, and it was lower in H rats (90 +/- 2%) than in N rats (95 +/- 2%). Lungs were isolated and perfused with saline, and those from H rats and N rats showed similar pulmonary vasodilator responses to 2 and 20 micrograms/kg beraprost. These results indicate that although beraprost caused a similar degree of acute pulmonary vasodilation in H and N rats, in H rats the response lasted longer. Thus PGI2 derivatives may be useful as vasodilators in some patients with primary and secondary pulmonary hypertension.

Animals↗
PubMed1994

Calcification in carcinoma of the stomach: report of a case.

By upper gastrointestinal series, a 57 years-old woman was pointed out to have scattered calcifications along the greater curvature of the stomach. On computerized tomography, the calcifications distributed in the irregularly thickened gastric wall. With a diagnosis of calcified mucinous adenocarcinoma showing Borrmann type III, total gastrectomy with splenectomy was carried out. The characteristics of this lesion were briefly presented with a review of the literature.

Adenocarcinoma, Mucinous↗
PubMed1994

Endoscopic resection of large colorectal polyps using a clipping method.

PURPOSE: In conventional endoscopic snare polypectomy, bleeding and perforation are the principal concerns. To prevent these complications, we employ an endoscopic clipping technique using the HX-3L clipping apparatus. METHODS: With this method, clips are used to clamp the base of a polyp. A snare is hung peripheral to the clips. The polyp is then resected by coagulating and cutting with an electric current. RESULTS: Neither bleeding nor perforation during or after polypectomy has occurred, nor have complications related to the use of clips developed. Gigantic polyps were not resected piecemeal, but rather were resected en bloc facilitating a clear determination of cancer on the surface of the resected site. Endoscopic clipping permitted site marking for colonoscopic surveillance. CONCLUSION: We conclude that the clipping method has many advantages and is a useful technique in colonoscopic polypectomy.

Adult↗