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Biomedical subjects

S Hashimoto

Publications and source records attributed to S Hashimoto.

At least 1,171 records · Page 65Linked to original sources
PubMed1985

Dystrophic axons in the nucleus gracilis of the normal rat containing cholecystokinin-like immunoreactivity. Light- and electron-microscopic observations.

Cholecystokinin immunoreactive (CCKI) axons in the nucleus gracilis of the normal rat were studied by light and electron microscopy using the peroxidase-antiperoxidase (PAP) immunocytochemical method. Immunoreactivity was found in both normal and dystrophic axons at various ages. Slightly enlarged CCKI varicosities were first observed in 2-month-old rats, gradually increased in number (max. at 21 months) and in diameter (up to 20 micron at 21 months), and then decreased (at 27 and 36 months). Dilatated CCKI fibers continuous with dystrophic varicosities also tended to increase proportionally in diameter. The dystrophic CCKI axonal profiles, first identified at the light-microscopic level and then observed under electron microscopy, had consistently characteristic features. In addition, numerous dystrophic nonreactive axonal profiles had morphological features differing from those of dystrophic reactive ones at advanced ages. These findings suggest that CCK may be partly involved in the formation of dystrophic axons in the nucleus gracilis.

Aging↗
PubMed1985

Relationship between perivaterian diverticulum and biliary tract disease.

The findings in 107 cases of perivaterian diverticulum diagnosed by endoscopic retrograde cholangiopancreatography (ERCP) were discussed in relation to complicated biliary tract disease. The incidence of abnormality in both gallbladder and bile duct, especially in extrahepatic bile ducts, was more frequent in cases of perivaterian diverticuli more than 11 mm in diameter. Perivaterian diverticuli was most frequently located on the oral side of papilla. Cases with papilla in a diverticulum showed more frequent biliary tract abnormality. Abnormal findings of the distal portion of common bile duct, such as flexion, compression and tapering, were noted in 31% of 107 cases. These findings were seen more frequently in cases with papilla in a diverticulum or with a diverticulum more than 11 mm in diameter. It is considered that these data suggest a mechanism of occurrence of biliary tract disease in cases with perivaterian diverticulum.

Adult↗
PubMed1985

Conversion of T-stages of nasopharyngeal carcinoma by computed tomography.

Thirty-six patients with nasopharyngeal carcinoma (NPC) were examined with computed tomography (CT) before definitive radiation therapy. CT clearly delineated the extent of the primary tumors. CT frequently showed subtle destruction of the paranasal sinuses and pterygoid plate, which was not usually detected by conventional X ray examinations. T-staging was made according to the UICC TNM classification system (1978) or another system, depending on clinical findings and the conventional X ray examinations (non-CT T-stage). Then, the non-CT T-stage of each patient was compared with T-stage diagnosed with CT findings alone (CT T-stage). CT upstaged non-CT T-stage in 14 of the 36 patients according to either system. Only one patient was downstaged by CT; this patient had cranial nerve palsy but not detectable bone destruction as shown by CT. We conclude that CT is the single, most reliable imaging method for primary tumors of NPC patients. Since CT detects subtle bone destruction, however, a large number of patients will be classified as having advanced tumors. Further modification of the TNM system may be needed for NPC patients in this era of CT.

Carcinoma, Squamous Cell↗
PubMed1985

Monoclonal antibodies to human protein C: effects on the biological activity of activated protein C and the thrombin-catalyzed activation of protein C1.

Thirteen monoclonal antibodies designated as MFC-1 to MFC-13 were obtained from hybridoma cells cloned after the fusion of mouse myeloma cells with spleen cells of mice immunized with purified human protein C. Studies were made to determine where the antibodies bound to the molecule of protein C and whether they affected the biological actions of protein C. By using the immunoblotting technique, six of these antibodies were shown to bind to the light chain of protein C, and five to the heavy chain of protein C and also activated protein C. The remaining two antibodies bound to neither the light chain nor the heavy chain, though both antibodies bound to the intact protein C. Antibodies specific for the light chain did not bind to the gamma-carboxyglutamic acid-domain. Two of the antibodies specific for the heavy chain (MFC-13 and -1) inhibited the amidolytic activity of activated protein C. The MFC-13 also inhibited the activity of bovine activated protein C, but not that of human Factor IXa, Factor Xa, or thrombin. In addition to these two antibodies, another one for the heavy chain (MFC-10) and two antibodies for the light chain (MFC-9 and -11) inhibited the inactivation of Factor Va by human activated protein C. One of the antibodies which inhibited the enzyme activity (MFC-1) blocked the inhibition of activated protein C by protein C inhibitor. Another one for the heavy chain (MFC-5) inhibited the activation of protein C by thrombin regardless of the presence or absence of thrombomodulin. Based on these results, we have established the positions of some monoclonal antibody-binding sites on the protein C molecule.

Animals↗
PubMed1985

Renin and angiotensin-converting enzyme in human neuroblastoma tissue.

High activity of renin was demonstrated in human neuroblastoma tissue. This activity was inhibited by specific antibody raised against human renal renin, indicating that it was not due to the nonspecific action of proteases. The specific activity of renin was 122.8 ng of angiotensin I generated mg of protein-1 h-1. It shared some biochemical features with well-known kidney renin, such as molecular weight, optimum pH, the presence of trypsin-activatable inactive renin, and glycoprotein nature. Furthermore, angiotensin-converting enzyme (ACE) activity (2.64 nmol mg of protein-1 min-1) was found in the tissue. This activity was inhibited by captopril, a specific ACE inhibitor, or by omission of chloride ion. These results suggest that true renin in addition to ACE exists in human neuroblastoma tissue.

Animals↗
PubMed1985

Wheat germ agglutinin inhibits the effects of nerve growth factor on the phosphorylation of proteins in PC12h cells.

Treatment of PC12h cells in tissue culture with nerve growth factor (NGF) led to an increased incorporation of [32P]orthophosphoric acid into specific proteins. The increased phosphorylation of 60,000-dalton and 20,000-dalton proteins in the 0.2% Triton X-100 detergent-soluble fraction, of 35,000-dalton protein in the 0.2% Triton X-100 detergent-insoluble fraction, and of slow migrating protein (SMP) in the nonhistone nuclear fraction was observed upon NGF treatment. On the other hand, wheat germ agglutinin (WGA) treatment of PC12h cells induced a slightly decreased phosphorylation of these NGF-responsive proteins. Incubation of cell-free extracts from PC12h cells with [gamma-32P]ATP led to the phosphorylation of a 100,000-dalton protein. In extracts from cells treated with NGF, the labeling of the 100,000-dalton protein was substantially and selectively reduced. In contrast, treatment of PC12h cells with WGA led to an increased phosphorylation of the 100,000-dalton protein in cell-free extracts. Thus, NGF and WGA showed opposite effects on the phosphorylation of specific proteins in both intact cells and cell-free extracts. In addition, it was also observed in both systems that pre- and posttreatment of PC12h cells with WGA abolished the effects of NGF on the phosphorylation and produced a phosphorylation pattern similar to that from PC12h cells treated only with WGA. In parent PC12 cells, it has been reported that the treatment of cells with WGA inhibits NGF binding to its receptors and converts the rapidly dissociating receptors to slowly dissociating receptors. Thus, WGA in conjunction with NGF, results in the practical disappearance of rapidly dissociating receptors on cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Gland Neoplasms↗
PubMed1985

True renin in human pituitary tissue.

Readily detectable levels of renin activity were demonstrated in human pituitary tissues. This activity was inhibited by specific antibody raised against human renal renin, indicating that it was not due to the nonspecific action of proteases. It shared some biochemical features with well-known kidney renin, such as molecular weight, optimum pH, and the presence of trypsin-activatable inactive renin. These results suggest that true renin exists in human pituitary tissue.

Adult↗
PubMed1985

Effect of shear rate on clot growth at foreign surfaces.

The hydrodynamic effect on clot growth at foreign surfaces was investigated quantitatively in vitro. Shear rates from 2 to 1,000 s-1 were applied to a blood sample contained in a cone and plate viscometer. Four different artificial materials were used for cone and plate combination, namely, stainless steel, polytetrafluoroethylene, polycarbonate, and polymethylmethacrylate. Evaluation of clot growth was derived from the clotting ratio (the volumetric fraction of clot in the whole blood), which was experimentally determined from the rate of increase of frictional torque between the rotating cone and the stationary plate. The results show that the clotting ratio decreases markedly as the shear rate increases to 400 s-1, regardless of material used. This study demonstrates that at a shear rate of greater than 400 s-1, clot growth at foreign surfaces is considerably inhibited.

Biophysical Phenomena↗
PubMed1985

Occupational pigmented contact dermatitis from azo-dyes.

A 51-year-old man had been working in a dye factory for 25 years and had noticed itching and pigmentation on the extremities for the past 5 years. Patch testing showed positive reactions to Sudan I and Vacanceine Red, among the azo dyes which he had been handling. After he changed his work, he became free from erythematous lesions with itching. The pigmentation almost disappeared 10 months later.

Azo Compounds↗
PubMed1985

Erythrocyte membrane fluidity decreased in uremic hemodialyzed patients.

Erythrocyte membrane fluidity was studied by means of electron spin resonance in 15 uremic, hemodialyzed patients and 14 normal subjects. Erythrocyte membrane fluidity determined using a 16-nitroxide stearic acid spin label probe was of a significantly lower level in the uremic patients, when compared with normal control subjects. Alterations in molar ratios of membrane free cholesterol to phospholipid are probably not a principal factor contributing to this change in fluidity. Significant decreases of phosphatidylcholine and molar ratios of phosphatidylcholine to sphingomyelin were noted in the erythrocyte membrane of uremic patients, and these alterations may relate to the fluidity change.

Adult↗
PubMed1985

Unusual pigmentation on the skin over trunk bones and extremities.

6 young people (19-31 years old) exhibited unusual light or dark brown, ill-circumscribed or reticular pigmentation distributed over protrudent bones. 5 of them have been using nylon towels and scrub brushes for over 3-10 years. Biopsy specimens showed that the amount of melanin granules in the basal layer was increased and melanophages were scattered in the upper dermis. Inflammatory infiltrates were minimal.

Adult↗
PubMed1985

Improvement of abnormal pyruvate metabolism and cardiac conduction defect with coenzyme Q10 in Kearns-Sayre syndrome.

In a patient with Kearns-Sayre syndrome, concentration of coenzyme Q10, a component of the mitochondrial electron transport system, was decreased in serum and in the mitochondrial fraction of skeletal muscle. Serum concentrations of lactate and pyruvate were abnormally high, especially after exercise or oral glucose loading. Levels of folic acid in plasma and CSF were decreased. ECG showed a first-degree atrioventricular block. After administration of coenzyme Q10 60 to 120 mg daily for 3 months, serum levels of lactate and pyruvate became normal, with improvement of atrioventricular block and ocular movements.

Adult↗
PubMed1985

Immunoreactive renin in human brain: distribution and properties.

Readily detectable levels of renin activity were demonstrated in the human brain. This activity was inhibited by specific antibody raised against human renal renin, indicating that it was not due to the nonspecific action of proteases such as cathepsin D. The pineal gland was found to be the richest source of renin followed by the pituitary, hypothalamus and hippocampus. The substantia nigra, caudate nucleus, putamen and thalamus contained moderately high concentrations of renin. The brain renins from pineal and pituitary glands shared some biochemical features with well-known kidney renin, such as molecular weight (46,000 daltons for pineal renin; 37,000-45,000 daltons for pituitary renin), optimum pH (6.0-7.0), the presence of trypsin activatable inactive renin, and a glycoprotein nature. However, the electrofocusing pattern of renin from pituitary tissue (pI = 4.43, 5.77) differed from that of plasma and kidney enzymes heretofore reported, a discrepancy which could be interpreted as evidence for the endogeneous synthesis of renin in the brain tissue. Furthermore, a high activity of immunoreactive renin was found in human neuroblastoma tissue. The biochemical characteristics of the neuroblastomal renin were generally similar to the known properties of kidney renin in many respects, providing evidence of the presence of the renin-angiotensin system within human neuronal cells.

Brain↗
PubMed1985

Evidence for existence of inactive arterial renin-like enzyme in the rat.

Inactive renin-like enzyme(s) in the arterial wall of the rat are converted to active renin-like enzyme in vitro by either "acid activation" (dialysis to pH 3.3 followed by dialysis to pH 7.4) or "protease-induced activation" (trypsin, alpha-chymotrypsin and glandular kallikrein). The molecular weights of the inactive renin-like enzyme(s) before trypsin activation were estimated to be about 68,000, 44,000, 36,000 and 30,000 by column chromatography. These findings may offer a new aspect for the role of the arterial renin-angiotensin system in the local control of vascular tone by interconversion of the inactive to the active renin-like enzymes in the arterial wall.

Animals↗
PubMed1985

Distribution of 201Tl in the blood.

Thallium-201 distribution in the blood was investigated both in vivo and in vitro. Thallium-201 was distributed into the erythrocytes and plasma with the ratio of 1.4 +/- 0.3 to 1.0, immediately after its administration. The uptake of 201Tl into the erythrocytes in vitro were affected by the incubation temperature and the presence of ouabain and KCl; indicating that the 201Tl was uptaken into cells partly through their membranes Na, K-ATPase. Erythrocytes could retain 201Tl in it, whereas 201Tl was present as free ion in the plasma. Thallium-201 was flew out of erythrocytes into the plasma, keeping the ratio of 201Tl in erythrocytes/plasma to be 1.9 +/- 0.2/1.0.

Erythrocyte Membrane↗