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Biomedical subjects

S Kato

Publications and source records attributed to S Kato.

At least 1,315 records · Page 73Linked to original sources

Approximate surface development of the left side half-trunk by a free-formed model.

The approximate surface development, skin length, and surface area of the left side of the trunk of 51 female students were compared with regard to static and stretched postures. The data for each subject were obtained from geometrical models generated by moiré topography with a computer. When the chest was stretched, the anterior surface, the shoulder line, and the arm-base line were transformed from concave to convex, and a gap oriented toward the nipple widened out. The skin elongated vertically and transversely, except at the side of the waistline, where the skin contracted. The area at the top of the trunk decreased about 25%, while the other parts of the trunk increased 8-15%. The total anterior area was 1.20 m2 for the static posture and 1.29 m2 for the stretched posture. When the posterior surface was stretched, the shoulder line changed from convex to concave, the side line from quasi-straight to concave, and gaps oriented toward the chest line disappeared. The skin elongated most at the infrascapular region (20-35%), while the neck base line contracted (-11%). The center of the back and the lower arm base areas enlarged the most (25%) and the lumbar area enlarged the least (12%). The total posterior area was 1.26 m2 in the static posture and 1.37 m2 in the back-stretched posture. In conclusion, the back skin elongated and enlarged more when stretched than the frontal skin.

Adult↗

Percutaneous pulmonary angioscopy using a guiding balloon catheter.

The applicability of angioscopy for observation of the pulmonary arterial lumen was examined in 7 anesthetized dogs and in 10 patients with various heart diseases during cardiac catheterization. A novel guiding balloon catheter (#11F shaft diameter and 1.5 cm in balloon diameter) was introduced through the right femoral vein into the pulmonary artery by Seldinger's method. Then, a fiberscope (1.3 or 1.8 mm in diameter) was introduced through the guiding catheter into the desired portion of the artery. The balloon was inflated, saline was infused, and the pulmonary arterial lumen was photographed on 16-mm color cinefilms. In all dogs and patients examined, an increase in diameter of the pulmonary artery during systole and the backflow of blood from the pulmonary vein were clearly demonstrated. Also, pulmonary thrombi or emboli experimentally induced in dogs could be observed. No complications were observed in the patients. The results indicate the experimental and clinical applicability of angioscopy using a guiding balloon catheter for observation of the pulmonary arterial lumen.

Adult↗

Intralobular lymphatic vessels and their relationship to blood vessels in the mouse thymus. Light- and electron-microscopic study.

The spatial distribution and fine structure of the lymphatic vessels within the thymic lobules of normal and hydrocortisone-injected mice were studied by light- and electron microscopy. The lymphatic vessels of the cortex and medulla of normal thymus are irregularly shaped spaces closely associated with branches of the intralobular artery and vein. The overall distribution of these vessels in the greatly involuted thymus of hydrocortisone-treated mice is essentially the same as in the normal thymus. The wall of the lymphatic vessels consists of only a layer of endothelial cells supported by underlying reticular cells. The luminal surface of the endothelial cell is smooth, but trabecular processes are often seen. There are three morphological types of intercellular contacts between contiguous cells, namely, end-to-end, overlapping and interdigitating. The lymphatic vessel has anchoring filaments and collagen fibrils, but a basal lamina is either absent, or if present, is discontinuous. This is in contrast to the continuous basal lamina of the venule. The perivascular space surrounding the postcapillary venule opens into a terminal lymphatic vessel at the cortico-medullary junction and in the medulla. Lymphocytes are seen penetrating the lymphatic endothelium, particularly in acutely involuted thymuses. These findings suggest that the intralobular lymphatic vessels may originate from the vacuities that surround the postcapillary venules, and the lymphatic system may function as a pathway for the migration of lymphocytes into or out of the lymphatic circulation.

Animals↗

Suppression of acute experimental allergic encephalomyelitis by synthetic serum thymic factor. Clinical, histopathological, and immunohistochemical studies.

Acute experimental allergic encephalomyelitis (EAE) was induced in Hartley guinea pigs and Lewis rats, which were then treated with synthetic serum thymic factor (FTS). When a dose of 30 micrograms/100 g body weight of FTS was subcutaneously administered to the animals on days--1 (before inoculation), 4, 9 and 15 intermittently, clinical symptoms of acute EAE were suppressed. Histopathological evaluation showed that the severity of EAE in FTS-treated guinea pigs was less than in untreated guinea pigs. Immunohistochemical examination showed that the numbers of OX6+, W3/25+, W3/13+ and OX19+ cells in FTS-treated rats were less than in untreated rats and that the number of OX8+ cells in FTS-treated rats was greater than in untreated rats. These findings suggest that FTS induced OX8+ cells in inflammatory lesions and suppressed inflammation in acute EAE.

Animals↗

Neuropathological study on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine of the crab-eating monkey.

Experimental parkinsonism was induced by systemic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to the crab-eating monkey (Macaca fascicularis). In the acute stage, the substantia nigra showed necrotic nerve cells, extracellular release of pigment granules and histiocytic infiltration. The nerve cells underwent vacuolation of the cytoplasm with chromatin clumping of the nucleus and disintegration of the nucleolus. The striking feature was the presence of variously-shaped inclusion bodies within abnormal mitochondria which sometimes disclosed a distortion of the cristae. Golgi apparatus and endoplasmic reticulum were also dilated. In the locus ceruleus swollen nerve cells were observed with vacuolated cytoplasm and pyknotic nucleus where expanded mitochondria also contained the inclusions. Some of the inclusion bodies are probably insoluble precipitations due to inhibition of mitochondrial oxidation by a certain metabolite of MPTP. In the protracted stage the substantia nigra revealed a considerable loss of the nerve cells associated with melanophagia and astrocytic proliferation. A few surviving nerve cells showed an increased number of Golgi apparatus and rough endoplasmic reticula, and the presence of autophagosomes, dense bodies and intra-mitochondrial inclusion. These changes are interpreted as being a part of the reparative process from the cellular damage.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗

Phorbol esters enhance attachment of NIH/3T3 cells to laminin and type IV collagen substrates.

The effect of phorbol esters on the adhesive properties of NIH/3T3 mouse fibroblasts was investigated using plastic substrates precoated with the extracellular matrix proteins fibronectin, collagen, and laminin. Treatment with phorbol 12-myristate 13-acetate (PMA) enhanced NIH/3T3 cell attachment to laminin and type IV collagen substrates but had little or no effect on attachment to fibronectin and type I collagen substrates. The effect of PMA in enhancing cell attachment to laminin and type IV collagen substrates was dose dependent between 10(-9) and 10(-7) M. PMA was effective as early as 30 min; the effect reached a maximum at 2 h and decreased gradually. Phorbol 12, 13-dibenzoate and phorbol 12, 13-diacetate were effective but to a lesser extent and phorbol 12-myristate and phorbol 13-acetate showed little or no effect. These results suggest that PMA may enhance NIH/3T3 cell adhesion through effects on laminin and type IV collagen receptors. Retinoic acid, which itself requires at least 6 h to show an effect on attachment, did not have any effect on cell attachment in 2 h and, if anything, slightly inhibited PMA-enhanced cell attachment to laminin and type IV collagen substrates.

Animals↗

Modification of DNA by mitomycin C in cancer patients detected by 32P-postlabeling analysis.

DNA adducts of mitomycin C (MMC) were detected by 32P-postlabeling analysis in both surgical specimens and an autopsy sample of the liver of patients with hepatocellular carcinoma who had received chemotherapy with MMC. Four kinds of adducts were detected in all 6 patients treated with MMC. These adducts had identical chromatographic mobilities to those of adducts in the liver of rats treated with MMC, but 1 additional adduct was detected in rat liver. In patients treated with MMC, about 3 adducts/10(8) nucleotides were found 4 days after MMC treatment, and 1 adduct/10(8) nucleotides 14 days after treatment and the latter level was maintained for up to 56 days. MMC-DNA adducts were also detected in peripheral blood leukocytes from a patient 1 and 7 days after MMC treatment, at levels of 1 and 0.6 adduct/10(8) nucleotides, respectively. These results suggest the tumor-initiating activity of MMC in humans.

Animals↗

The effects of estrogen, insulin and dexamethasone on the synthesis and secretion of egg white proteins in primary cultured oviduct cells of laying Japanese quail (Coturnix coturnix japonica).

1. The effects of estrogen, insulin and dexamethasone on the synthesis of egg white proteins were investigated by employing primary cultured oviduct cells of laying Japanese quails. 2. It was demonstrated that oviduct cells require insulin and dexamethasone, besides estrogen, to synthesize and secrete egg white proteins maximally.

Animals↗

Alumina ceramic prosthesis arthroplasty of the metacarpophalangeal joint in the rheumatoid hand. A 2-4-year follow-up study.

Swanson's finger implant is being widely used to improve deformity of the thumb and finger and to restore function in the rheumatoid hand. Breakage of the implant and implant synovitis have been the most troublesome complications. The authors developed an alumina ceramic finger prosthesis to lessen these complications. This prosthesis was used for the metacarpophalangeal joint in 5 cases of flexion deformity of the thumb and in 21 cases (82 digits) with ulnar drift deformity. These cases were followed for 24-62 months (average, 38 months). Postoperative extension of the thumb was limited to 18 degrees and flexion was 48 degrees, on average. Postoperative range of motion was 30 degrees. The average limitation of extension of all digits was 18 degrees, and the average flexion was 54.5 degrees. The average range of motion was 36.5 degrees. Flexion deformity of the metacarpophalangeal joint of the thumb disappeared after operation, and ulnar drift was reduced to less than 10 degrees deviation in 87.8%. No dislocation or fracture of the prosthesis has been found on roentgenologic examination during short-term follow-up study. This prosthesis is useful for reducing deformity of the thumb and the finger in the rheumatoid hand. Postoperative extension of the metacarpophalangeal joint, however, has been unsatisfactory. The design of the prosthesis should be improved so that the rotational center of the metacarpophalangeal joint is located palmarly.

Adult↗

An outbreak of foodborne hepatitis A in a factory: a possible shift in age of patients in Japan.

We investigated extensively an outbreak of hepatitis A at a factory in suburban Nagoya. Epidemiological study indicated a foodborne outbreak by a supplier of lunches. Serologically, all the employees younger than 30 years of age had been susceptible to hepatitis A virus, but the highest morbidity was observed in the 40-44 age group. The age difference in morbidity from foodborne hepatitis and susceptible populations suggests a shift in mean patient age linked to a shift in antibody prevalence to hepatitis A virus. In communities where the prevalence started shifting after development of sanitary systems, effective prophylaxis for foodborne hepatitis A will be necessary to prevent the disease in an increasing number of older patients in a few decades.

Adult↗

In vitro reaction of hydroxyamino derivatives of MeIQx, Glu-P-1 and Trp-P-1 with DNA: 32P-postlabelling analysis of DNA adducts formed in vivo by the parent amines and in vitro by their hydroxyamino derivatives.

The synthetic hydroxyamino derivatives of three mutagenic and carcinogenic heterocyclic amines present in cooked foods and amino acid pyrolysates, 2-amino-3,8-dimethylimidazo-[4,5-f]quinoxaline (MeIQx), 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), were reacted with DNA in vitro. Their reactivities were increased by addition of 10-fold excess of acetic anhydride. 32P-Postlabelling analysis of the adducts formed in these in vitro reactions revealed that almost all the adducts of the hydroxyamino derivatives of MeIQx and Glu-P-1 were the same as those formed in liver DNA of rats intragastrically treated with the parent amines. In contrast, analysis of Trp-P-1--DNA adducts showed that the adducts formed in vitro were minor components of those formed in vivo; the two main adducts formed in vivo were not formed in vitro. Thus, MeIQx and Glu-P-1 may be metabolized in vivo to hydroxyamino derivatives and/or their esterified forms, such as N-acetoxy derivatives that form DNA adducts. Formation of adducts by Trp-P-1, however, may occur through more complicated metabolic pathways. Elucidation of the structures of DNA adducts in vivo is necessary to clarify this problem.

Animals↗

Detection of gangliosides as N-glycolylneuraminic acid-specific tumor-associated Hanganutziu-Deicher antigen in human retinoblastoma cells.

Gangliosides were shown to bear the tumor-associated N-glycolylneuraminic acid (NeuGc)-specific Hanganutziu-Deicher (HD) antigen expressed in human retinoblastoma cells. HD antigenic gangliosides were detected by thin-layer chromatography/enzyme-immunostaining using affinity-purified chicken antibody against GM3 containing NeuGc and horseradish peroxidase-conjugated anti-chicken IgG. One to four species of the antigenic gangliosides were detected from all of 4 cell lines, Y79, WERI-Rb1, TOTL1, and YK, as well as freshly cultured retinoblastoma cells and isolated tumor tissue. All cases contained GM3(NeuGc) as an HD antigen. No HD antigenic ganglioside was detected in normal retinal tissues by the same procedure.

Antigens, Heterophile↗

Defective human immunodeficiency virus (HIV) particles produced by cloned cells of HTLV-I-carrying MT-4 cells persistently infected with HIV.

Persistently HIV-infected cell lines were isolated from surviving and proliferating cells after infection of HTLV-I-carrying MT-4 cells with cell-free human immunodeficiency virus (HIV); HTLV-IIIB and LAV. The media of the cloned cell cultures did not cause HIV infection of MT-4, MOLT-4, TALL-1, or HL-60 cells. Most of the constituents of the virus in the media were env proteins and many defective doughnut-shaped particles released from the cells were identified by electron microscopy.

Cell Line↗

Hereditary hemorrhagic telangiectasia with malignant lymphoma. An autopsy case.

A 60-year-old Japanese woman was diagnosed at autopsy as having had hereditary hemorrhagic telangiectasia (HHT) associated with systemic hemangiomas. In her reproduction period, premenstrual epistaxis frequently occurred. At the age of 60, the patient died of malignant lymphoma. At autopsy, multiple telangiectatic spots were noted on the face, limbs and trunk. The paraaortic lymph nodes, which were enlarged and irregularly conglomerated, were histologically diagnosed as malignant lymphoma of the diffuse large cell type. Submucosal telangiectatic lesions were found in the gastrointestinal system from the oral cavity to the rectum. Cavernous hemangiomas were present in various visceral organs including the liver, spleen, small and large intestines, rectum, appendix, uterus, and jejunal and colonic mesenteries. There was an arteriovenous fistula in the left lung. Examination of her family pedigree showed that the patient had an autosomal dominant trait of inheritance. The pathogenesis of the systemic visceral hemangiomas observed in this patient was considered to be similar to that of harmartoma.

Female↗

Endogenous peroxidase activity in primary culture of human thyroid cells. Localization and measurement.

Intracellular localization of and an assay method for endogenous peroxidase (PO) activity were studied using primary culture of thyroid cells obtained from patients with hyperthyroidism. PO activity was visualized by cytochemical reaction and was located mainly in perinuclear cisternae and rough endoplasmic reticulum. With increased culture time, the number of cells showing positive PO activity and amount of the enzyme reaction product in individual cells showed a parallel decrease. For measurement of PO activity, cultured thyroid cells were frozen and thawed and then incubated with citric acid buffer solution containing o-phenylenediamine (opd) and hydrogen peroxide. After incubation, the optical density (OD) of the solution colorized by endogenous peroxidase was measured at 405 nm using a microplate reader. About 1 X 10(4) cells were sufficient for assay of PO activity. Using the above method to assay PO activity and sandwich enzyme immunoassay for thyroglobulin (TG), chronological changes in the PO activity and TG concentration in the culture medium were examined. Although the cells showed no decrease in number, PO activity and TG concentration decreased chronologically. When the ratio of PO activity to TG concentration was calculated, in 3 cases the ratio was almost constant, and in the remaining two, it decreased chronologically. The present biochemical method thus seems useful for determining peroxidase activity of cultured thyroid en masse.

Cells, Cultured↗

GABAergic inhibition on dopamine cells of the fish retina: a [3H]dopamine release study with isolated fractions.

Inner retinal cells including dopamine (DA) cells were isolated and fractionated from the carp (Cyprinus carpio) retina by an enzyme cell dissociation and metrizamide gradient centrifugation method. When gamma-aminobutyric acid (GABA) antagonists (bicuculline and picrotoxin) were added into the perfusate over such a cell fraction, they stimulated the release of [3H]DA which had been preloaded in the cell fraction. The action of GABA antagonists was dose and Ca2+ dependent. Their minimal effective concentration was very low (0.5 microM). A similar action was elicited by high K+. In the presence of excess GABA, this stimulatory action of GABA antagonists and high K+ on [3H]DA release was completely abolished. To interpret the action of GABA antagonists on DA cells, isolated cell fractions were preincubated with GABAse. After such a treatment, the stimulatory effects of GABA antagonists and high K+ on [3H]DA release were differentiated from each other; the former disappeared whereas the latter remained unchanged. The data strongly suggest that GABA inhibits the DA release from retinal DA cells and thus the GABA antagonists affect [3H]DA release from cell fractions not by a direct membrane action but by a disinhibition mechanism via GABA receptors on the DA cell bodies.

4-Aminobutyrate Transaminase↗