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Biomedical subjects

S Hashimoto

Publications and source records attributed to S Hashimoto.

At least 919 records · Page 51Linked to original sources
PubMed1989

Antibodies to beta 2-microglobulin, the light-chain component of class I histocompatibility molecules, provide an activation signal to human lymphocytes.

Antibodies to beta 2-microglobulin (beta 2m), the light-chain component of class I histocompatibility antigens, provide a strong co-stimulatory signal to human lymphocytes in the presence of phorbol ester. This activation signal requires a high concentration of antibody, whereas the effect on responses to a mitogenic lectin is exclusively inhibitory over a broad dose range. A rabbit polyclonal and a mouse monoclonal antibody to beta 2m were similarly co-stimulatory. Antibody to beta 2m was co-stimulatory with phorbol ester, but not calcium ionophore, suggesting that class I antigens play a role in the initiation of the 'first' signal of a recently described two-signal model of lymphocyte activation.

Antibodies↗
PubMed1989

Blockage of nerve growth factor action in PC12h cells by staurosporine, a potent protein kinase inhibitor.

Staurosporine, which has a structure similar to that of K-252a, a potent protein kinase inhibitor that blocks nerve growth factor (NGF) action in PC12 and PC12h cells, is also known as a potent inhibitor of several protein kinases. This study shows that in PC12h cells staurosporine has a dual action: at lower concentrations than that required by K-252a, it is an inhibitor of NGF induction of neurite formation and of changes in the phosphorylation of specific proteins, whereas at concentrations higher than that required to inhibit NGF-induced neurite outgrowth, it rapidly enhances outgrowth by itself.

Adrenal Gland Neoplasms↗
PubMed1989

Erythrocyte destruction under periodically fluctuating shear rate: comparative study with constant shear rate.

The hydrodynamic effect of periodically fluctuating shear rate on erythrocyte destruction was quantitatively studied in vitro in comparison with constant shear rates. Uniform shear rates (less than 1,000 s-1; constant or sinusoidally fluctuating with time) were applied to heparinized canine blood contained in the concavo-convex type of Couette flow testing machine for (1.8-9.0) x 10(3) s at 24 degrees C. The results show that the erythrocyte destruction (evaluated with hemolysis ratio; plasma hemoglobin count per whole blood hemoglobin count) decreases when the exposure time of larger (greater than 500 s-1) shear rates is interspersed with smaller (less than 300 s-1) shear rates.

Erythrocytes↗
PubMed1989

A newly designed flow-regulating device in shunt therapy of hydrocephalus.

A new flow-regulating device for shunting in hydrocephalus was designed to limit an excess flow by a pressure-head between the cerebral ventricle and the abdominal cavity in a standing position. The device has two diaphragm valves connected to each other by two lines: one is a shunting line to transfer cerebrospinal fluid and the other is a control line filled with a control fluid with a higher density than cerebrospinal fluid. The performance of the model device with a natural rubber sheet diaphragm was tested in a mock system, using glycerol for the control fluid and water for the transfer fluid in vitro. Results show that device decreases the excess flow when the pressure-head between two valves exceeds 35 cm.

Cerebrospinal Fluid Shunts↗
PubMed1989

A cytochemical study of dense granules in the rat junctional epithelium.

To clarify the details of intracytoplasmic granules in the junctional epithelium (JE) of the rat gingiva, phosphotungstic acid (PTA) staining, acid phosphatase cytochemistry and zinc iodide-osmium (ZIO) staining were carried out. Condensing granules containing homogeneous electron-dense materials, measuring about 260 nm in diameter, have been observed at the peripheral cytoplasm of the JE. These granules reveal PTA-positive, ZIO-positive and acid phosphatase-positive staining. These results indicate that the granules contain glycoprotein, phospholipid, lipoprotein and lysosomal enzymes. From their composition and morphology, it is suggested that these granules in the JE may contribute secretory function and secrete glycoproteins or glycolipids. Although it is unclear whether the dense granules correspond to membrane-coating granules by our staining methods, it is surmised that, if the dense granules can engage in establishment of the barrier function, then this role is impeded by the large intercellular space in the JE.

Acid Phosphatase↗
PubMed1989

Lymphocyte subpopulations of peripheral blood in tsutsugamushi disease.

We examined lymphocyte subpopulations in the peripheral blood and serum concentrations of immunoglobulin (Ig) in 8 patients with tsutsugamushi disease. In 7 of the 8 cases, there was a 4-fold or greater increase in IgG and IgM antibody titers between the initial and convalescent serum specimens. In one case, there was no increase, but IgM antibodies were detected with diagnostically significant antibody titers. The percentages of CD8- and CD2-positive lymphocytes measured before treatment were found to be significantly higher than during the recovery stage of patients with tsutsugamushi disease. The CD4/CD8 ratio in the peripheral blood calculated before treatment was significantly lower than that during the recovery stage. Serum concentrations of IgG and IgM in patients during the recovery stage were significantly higher than pretreatment levels, respectively.

Adult↗
PubMed1989

Adult T cell leukemia in hemodialysis patients from the Kagoshima district, an area in which human T cell leukemia virus type I is highly endemic.

We report 2 cases of adult T cell leukemia (ATL) from hemodialysis (HD) patients with chronic renal failure (CRF) in the Kagoshima district, an endemic area of human T cell leukemia virus type I(HTLV-I) in Japan. The positivity of antibodies to ATL-associated antigen(anti-ATLA) in HD patients, regardless of whether or not blood transfusions were given, has been higher than in healthy persons in the district (p less than 0.01). ATL is considered to break out from HTLV-I carriers. Further study should be conducted to clarify the relationship between HTLV-I infection and CRF, and moreover, attention should be directed not only to treatment of HD but accompanying ATL as well, particularly in HTLV-I-endemic areas.

Aged↗
PubMed1989

Wheat germ agglutinin, concanavalin A, and lens culinalis agglutinin block the inhibitory effect of nerve growth factor on cell-free phosphorylation of Nsp100 in PC12h cells.

It has been shown that in PC12 and its subclone PC12h treatment of the cells with nerve growth factor (NGF) induces a selective decrease in the incorporation of radioactive phosphate into a 100,000-dalton protein, designated in an earlier study as Nsp100, in the subsequent phosphorylation of soluble extracts from cells with (gamma-32P)ATP. In the present study, we show that plant lectins, wheat germ agglutinin (WGA), concanavalin A (Con A), and lens culinaris agglutinin (LCA), inhibit the action of NGF on Nsp100 phosphorylation in PC12h cells. Treatment of the cells with WGA, which binds to N-acetylglucosamine and sialic acid residues on glycoproteins, strongly blocked the inhibitory action of NGF on the protein phosphorylation. Con A and LCA, both of which recognize the same specific sugars (mannose, glucose), displayed only a moderate blocking effect. Unlike the native lectin, succinylated WGA, which has the ability to bind to N-acetylglucosamine but not to sialic acid residues, and other lectins examined in this study did not inhibit the action of NGF on Nsp100. WGA-mediated inhibition of NGF action was reversed by the addition of N-acetylglucosamine and by the addition of a much lower concentration of a sialoglycoprotein, mucin, into the culture. Since the binding of succinylated WGA to N-acetylglucosamine residues of cell-surface glycoconjugates is not sufficient to prevent the action of NGF, WGA might act on sialic acid residues of the NGF receptor molecule to effect the inhibition of biological actions of NGF.

Adrenal Gland Neoplasms↗
PubMed1989

[Left ventricular blood flow dynamics caused by ventricular premature contraction: pulsed Doppler echocardiographic study].

Cardiac function at the time of ventricular premature contractions (VPC) is influenced by the coupling interval or the site of those origin. Clinical and experimental studies of the effects of VPC on intracardiac pressure dynamics have been performed; however, little is known about left ventricular blood flow dynamics. This study was attempted to determine the characteristics of blood flow dynamics in respect to the site of origin of VPC using pulsed Doppler echocardiography. The subjects consisted of 18 cases with VPC but without apparent organic heart disease. Seven cases had VPCs with a left bundle branch block pattern suggesting possible origin in the right ventricle. The other 11 cases had VPCs with a right bundle branch block pattern indicating the left ventricular origin. With the probe in the apical position, the blood flow patterns of the left ventricular outflow, central and inflow tracts were examined. The results were as follows; 1. Except for one case with shortened coupling interval, all six cases with VPCs originated from the right ventricle showed preservation of left ventricular ejection flow. 2. In two of the three cases with VPC which originated from the left ventricle and with left axis deviation, systolic flow in the left ventricular central area showed "back flow" to the apex. Ejection flow at the outflow tract was markedly diminished or disappeared in all three cases. 3. In all eight cases with VPC which originated from the left ventricle and with right axis deviation, ejection flow was slightly disturbed both in the left ventricular outflow and in the central area. 4. Ejection flow volume assessed by velocity integral indicated similar dynamics as did the ejection flow velocity. 5. In left ventriculography, asynchrony due to dyskinetic motion of the anteroapical wall was observed at the times of VPCs with left axis deviation. In conclusion, the patterns of left ventricular ejection flow dynamics depend on the site of origin of VPCs. This disturbed flow is more apparent in VPCs originating from the left ventricle compared to the right ventricle. This is especially true in cases with left axis deviation, in which VPCs arise from the posterior site of the left ventricle.

Adolescent↗
PubMed1989

[A case of metastatic urinary bladder tumor from gastric carcinoma--especially mucohistochemical study].

We report a case of metastatic bladder tumor from gastric cancer, which was difficult to differentiate from urachal tumor preoperatively, especially computed tomographic scan, cystoscopy, and biopsy. A 51-year old man visited our hospital with the chief complaint of asymptomatic gross hematuria. He had received subtotal gastrectomy for gastric cancer two years earlier. Because the possibility of urachal tumor could not be excluded, en bloc segmental resection of the bladder, the urachus, and the umbilicus was carried out. This case was diagnosed as adenocarcinoma histologically, but it was difficult to determine whether the case was a metastatic bladder tumor from gastric cancer or urachal tumor by the routine staining method. High iron diamine-alcian blue and paradoxical concanavalin A (ConA) stainings were performed, on the surgical specimens of this case and other urachal tumor already diagnosed. In these cases, metastatic bladder tumor could be differentiated from an urachal one by mucohistochemically paradoxical Con A staining. Seventeen cases of metastatic bladder tumor from gastric cancer including our cases were collected from the Japanese literature and reviewed.

Adenocarcinoma↗
PubMed1989

[Expressions of 2H4 and 4B4 antigens on ATL cells].

We studied the expression of 2H4 and 4B4 on the surfaces of leukemia cells from 17 patients with adult T-cell leukemia (ATL) as well as of cells belonging to 2 T-cell lines derived from ATL patients. The effects of the supernatants obtained from culture fluids of the ATL cells and the T-cell lines on IgG production of a human B-cell line, CESS cells, were also examined. On the surfaces of the ATL cells from 15 out of 17 cases and of the cells of 2 T-cell lines 4B4 obviously existed at higher percentage than 2H4 and more than 80% of ATL cells from 16 out of these 17 cases showed the expression of T4 (CD4). These findings revealed that the most of ATL cells had a helper-inducer phenotype. Supernatants (Sups) of culture fluids of ATL cells from 4 patients and those of 2 T-cell lines were added at various concentrations to the CESS cells. In only 1 Sup from ATL patient enhanced the IgG production of the CESS cells at lower concentration. However, other 5 Sups suppressed the IgG production of the CESS cells in proportion to the increase of Sup added. These results showed that phenotypical type of ATL cells does not always correspond to their functions, and the ATL cells may produce humoral factors that regulate B cell functions.

Adult↗
PubMed1989

[Graves' disease complicated with systemic lupus erythematosus (SLE): a case report].

A 25 year old man had been subjected to subtotal thyroidectomy under the diagnosis of Graves' disease. About a year later the patient developed systemic lupus erythematosus (SLE). Reports on cases of Graves' disease complicated with SLE have barely been observed so far. Consequently, the authors reckoned, with reference to the other literatures on the subject, our case worth reporting.

Adult↗
PubMed1989

[Experimental radioimmunoimaging of human lung small cell carcinoma xenograft H-69 by NCC-ST-433 monoclonal antibody].

NCC-ST-433 monoclonal antibody raised against human gastric carcinoma xenograft (St-4) was labeled with 125I using enzymatic and Iodogen methods. While labeling efficiency of the antibody was more excellent by enzymatic method, specific radioactivity of the antibody labeled by Iodogen method was higher than that by enzymatic method. The labeled antibody was stable in vitro and in vivo, and the labeled NCC-ST-433 was specifically accumulated in NCC-ST-433 antigen positive human tumor cell lines in vitro. The specificity of 125I-NCC-ST-433 in vivo was found to be more excellent when this antibody was labeled by Iodogen method and actually excellent images of H-69, a human small cell lung carcinoma, were obtained 5 days after injection of 7 micrograms of 125I-NCC-ST-433 per mouse. This method seemed to be promising for imaging human lung small cell carcinomas.

Animals↗
PubMed1989

[A molecular basis for multidrug resistance and reversal of the resistance].

Multidrug-resistance is frequently characterized by enhanced drug efflux resulting from a membrane glycoprotein of 170,000 daltons (P-glycoprotein). Analysis of cloned cDNAs for the human MDR 1 gene, whose product is the P-glycoprotein, indicates that P-glycoprotein is an energy-dependent drug-efflux system for cytotoxic hydrophobic anticancer drugs. We have demonstrated that a photoanalog of a reversing agent, SDB-ethylenediamine, specifically binds to P-glycoprotein. The binding site on P-glycoprotein seems to be identical with that of anticancer agents and other reversing agents. On the other hand, the radioactive photoactive dihydropyridine calcium channel blocker, [3H] azidopine, photolabels P-glycoprotein in membrane vesicles from multidrug-resistant cells. This photolabeling is almost completely inhibited by excess dihydropyridine analogs that reverse or lower drug-resistance. In contrast, the labeling is not significantly inhibited by analogs that do not reverse resistance. These results suggest that it may be possible to quickly screen for dihydropyridine analogs that reverse multidrug resistance by measuring the inhibition of [3H] azidopine labeling of P-glycoprotein.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1989

[A newly devised continuous catheter flush system for arterial pressure monitoring].

Since Gardner et al. demonstrated a useful continuous catheter flush system in 1970, various systems for blood pressure monitoring have been commercialized. However, some problems have not been solved yet, such as hazard of embolism, infarction, unexpected infusion of large amount of fluid etc.. We have introduced a new type of flush system. which consists of disposable plastic unit with a one-way valve newly developed by us (SAT-route) and a syringe pump (Terumo STC-521). Using this system, only 0.5 ml.hr-1 infusion of heparinized saline was sufficient to prevent the formation of thrombus. Flushing was easily achieved by only pushing the purge button of the pump. As a result, simple, safe and high fidelity pressure monitoring was achieved without much altering the waveform of arterial pressure during flushing. The dynamic frequency response obtained from a square wave test was excellent, with natural frequency of about 40 Hz and damping coefficient of about 0.3. This system is useful especially for perioperative management of small children undergoing cardiac surgery, who require an exquisite infusion therapy and fluid restriction.

Blood Pressure Monitors↗