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Biomedical subjects

T Masuda

Publications and source records attributed to T Masuda.

At least 541 records · Page 30Linked to original sources
PubMed1988

Immunologic and clinical studies on murine experimental autoimmune gastritis induced by neonatal thymectomy.

Experimental autoimmune gastritis (AIG), defined by the appearance of auto antibodies to parietal cells, was induced by neonatal thymectomy in BALB/c nu/+mice 3 days after birth. Vitamin B12 absorption and intrinsic factor in the stomach extract decreased compared with those in AIG-negative control groups. No decrease of the serum A/G ratio in AIG-bearing mice was observed. Although development of anemia, as evaluated by a decrease in hematocrit value, was poor until 12 mo of age and the gastric mucosa was hypertrophic, the AIG resembled human pernicious anemia rather than Ménétrier's disease. Adoptive transfer of spleen cells, but not sera, of AIG-bearing nu/+ into BALB/c nu/nu mice caused AIG in all animals 1 mo later, indicating the involvement of lymphocytes in the induction mechanism of AIG. Cytofluorometric and immunohistochemical analysis of lymphocytes in the gastric mucosa revealed T-cell infiltration at an early stage (1.5-3 mo) followed by B cell infiltration (6 mo). When the fraction enriched with parietal cells, which were intensively stained with sera of AIG-bearing mice and fluorescent antibody to mouse immunoglobulin G, was injected into the foot pads of AIG-bearing nude mice, typical delayed-type hypersensitivity reaction was observed in all animals. This was not seen in the mice injected with the cell fraction enriched with chief cells, although a few of them were stained by the immunofluorescent technique. Thus, the delayed-type hypersensitivity reaction seems to be directly involved in the mechanism of tissue damage.

Anemia, Pernicious↗
PubMed1988

Combination assay of CA125, TPA, IAP, CEA, and ferritin in serum for ovarian cancer.

The levels of CA125, TPA, IAP, CEA, and ferritin in the serum were measured simultaneously in 68 healthy nonpregnant females and 133 patients with various gynecological diseases, and were subjected to statistical discriminant analysis for the diagnosis of ovarian cancer. The usefulness and the limits for diagnosis of various gynecological diseases were investigated for each tumor marker. Also, the diagnostic usefulness of the stepwise discriminant analysis employing the values of these five tumor markers in the serum in cases of ovarian cancer was compared with that of CA125 measurements alone. Because the frequency of cases with an elevated serum CA125 level increased more specifically in the ovarian cancer group than those of other tumor makers in the serum, this parameter was considered to be more useful for the diagnosis of ovarian cancer than the levels of the other tumor markers. The frequencies of cases with the elevated serum CA125 levels, however, also increased in the groups of patients with endometriosis and at an early stage of normal pregnancy more than in the group of healthy nonpregnant females. In the ovarian cancer patients, the discriminant analysis employing the values of CA125 and four other tumor markers in sera was more useful for early diagnosis, differential diagnosis, early detection of recurrences, and the determination of complete remission after therapy than the measurement of the serum CA125 level alone.

Antigens, Neoplasm↗
PubMed1988

Cytotoxic and mutagenic effects of emodin on cultured mouse carcinoma FM3A cells.

Employing a suspension culture of a mouse mammary carcinoma cell line, FM3A cells, the cytotoxicity and induced mutagenicity of emodin (EM) were examined and compared with those of 2-hydroxy-emodin (2-OH-EM), which was identified as an active form of EM in the Ames/microsomes assay. EM was cytotoxic to FM3A cells in concentrations of 1-10 micrograms/ml, and induced 6-thioguanine-resistant (6TGr) mutation. 2-OH-EM was a little more toxic than EM, but induced little mutation.

Animals↗
PubMed1988

DNA ploidy of colorectal carcinoma. Correlation with conventional prognostic variables.

The DNA content of tumor cells was determined in 51 cases of colorectal carcinoma and correlated with conventional clinicopathologic features. Normal diploid content of DNA was found in cells from 19 tumors, and aneuploidy was found in cells from 32 tumors. An aneuploid stemline of tumor cells appeared to be associated with advanced disease. However, a statistical analysis using Pearson's chi-square test disclosed no significant correlation between DNA ploidy of tumor cells and conventional clinicopathologic characteristics of colorectal carcinoma, such as differentiation, staging, lymph node status, and depth of invasion.

Adenocarcinoma↗
PubMed1988

Lethal graft-versus-host disease in nude mice. I. Establishment of model systems.

We examined whether nude mice, which are deficient in T cell function, could be used as a model for induction of lethal graft-versus-host disease. Nude mice injected with MHC-disparate spleen cells exhibited only transient GVH reaction such as splenomegaly. Inoculation of B6 spleen cells into BALB/c nude mice produced high titers of alloantibodies to the donor cells. These alloantibodies eliminated host-MHC-reactive donor T cells from the host. After abolition by 400 rads irradiation of the capacity of nude mice to produce antibody, lethal GVHD could be induced by allogeneic spleen cell transfer and was mediated by donor T cells. This lethal GVHD was prevented by prior administration of antidonor alloantibody to the irradiated recipients at least 24 hr before donor-cell grafting. The role of alloantibody was substantiated in 2 other combinations in which little or no alloantibodies to donor spleen cells were produced. Engraftment of either MHC-identical but non-MHC disparate donor spleen cells into BALB/c nude mice or of parental spleen cells into F1 nude mice resulted in death mediated by T cells. In addition, irradiated BALB/c nude mice inoculated with non-MHC-incompatible B10.D2 spleen cells were much more sensitive to alloaggression by the donor cells than were nonirradiated hosts, indicating the presence of some radiation-sensitive component(s) acting in nude mice against GVHD induction by donor T cells. Thus the nude mouse is considered to be a useful recipient for clarifying the basic mechanisms involved in lethal GVHD.

Animals↗
PubMed1988

High-grade surface osteosarcoma of the left ilium. A case report and review of the literature.

A rare case of high-grade surface osteosarcoma of the left ilium is reported. Trephine biopsy performed on a 31-year-old woman suffering from a huge tumor of the left buttock revealed high-grade osteosarcoma, and hemipelvectomy was undertaken. The surgical specimen showed that the tumor was present on the surface of the left ilium. Ten months after the operation, the patient died of brain metastasis. From these results, we considered this case to be one of high-grade surface osteosarcoma.

Adult↗
PubMed1988

Immunoreactive opsin and glial fibrillary acidic protein in persistent hyperplastic primary vitreous.

An 8-month-old boy had an anterior type of persistent hyperplastic primary vitreous in the right eye. Results of needle biopsy, performed because of elevated intraocular pressure, disclosed clusters of blastic cells. The eye was enucleated on the suspicion of retinoblastoma. Histological examination showed retrolental fibrovascular tissue and retinal dysplasia. Immunoreactive opsin was detected in the innermost structures and in photoreceptor-like cells of rosettes. We conclude that photoreceptor cells differentiated to express opsin, even when neighbouring cells were abnormally arranged. An immunocytochemical study of glial fibrillary acidic protein demonstrated glial proliferation in the inner layer of the retina but not in the preretinal space.

Eye↗
PubMed1988

Production and characterization of monoclonal antibodies specific for the transmembrane protein of simian immunodeficiency virus from the African green monkey.

Mouse monoclonal antibodies were produced against simian immunodeficiency virus (SIV) from the African green monkey (SIVAGM). The antibodies reacted with the transmembrane protein of all five SIVAGM isolates but not with those of SIVs from the rhesus macaque and mandrill or of human immunodeficiency virus type 1 or type 2, indicating that they recognize a species-specific epitope strongly conserved in SIVAGM. The transmembrane proteins of several SIVAGM isolates were found to vary in molecular size, even in the deglycosylated form after N-glycanase treatment, indicating heterogeneity of the SIVAGM isolates.

Animals↗
PubMed1988

Nociceptive body representation in nucleus ventralis posterolateralis of cat thalamus.

1. The somatotopic organization of nociceptive-specific (NS) and wide dynamic range (WDR) units in the nucleus ventralis posterolateralis (VPL) of the ventrobasal (VB) complex was studied. Experiments were carried out on adult cats anesthetized with urethane-chloralose. The recording sites of nociceptive units were marked by the electrophoretic deposition of pontamine sky blue from the recording microelectrode, and subsequently identified histologically in cresyl-violet stained sections. 2. It was found that NS units were located in the dorsal and ventral shell regions of the caudal VPL, whereas WDR units were located in a narrow zone of the shell region, just rostral to the NS zone. 3. NS units in the dorsal shell region had receptive fields on the contralateral dorsal surface of the body, whereas NS units in the ventral shell region had their receptive fields on the ventral aspect of the contralateral integument. 4. In the dorsal shell region, the contralateral body surface was represented in an orderly sequence. Units responding to noxious stimulation of the upper-most cervical dermatome were found in the most medial part of the shell region of the VPL, whereas those responding to stimulation of successively more caudal dermatomes were located more laterally, and in serial order. Units responding to noxious stimulation of the sacral dermatomes were thus found in the most lateral part. 5. In the ventral NS zone, the pattern was distorted by disproportionately large areas devoted to the fore- and hindpaw pads. In this region, therefore, NS units with receptive fields on the fore- and hindpaw pads were intermingled with other NS units that could have receptive fields located anywhere on the ventral body surface. It should be noted, however, that the remainder of the body surface was still represented in an orderly sequence; cervical dermatomes being represented medially, with successively more caudal dermatomes being represented progressively more laterally. 6. A similar somatotopic pattern was recognized in the distribution of the low-threshold centers of the receptive fields of WDR units.

Animals↗
PubMed1988

The link between free radicals and myocardial injury.

In the first part of this study, oxygen derived radicals (O2-radical) were indirectly demonstrated as causative agents for ischemia/reperfusion injury by showing myocardial protection of radical scavengers. In 19 open chest dogs, the left anterior descending coronary artery was occluded for 90 min and subsequently reperfused for 60 min. Group A received SOD (15000 U/kg), catalase (5 mg/kg) and 20% mannitol (18 ml/kg) via the left atrium starting 15 min pre-occlusion and ending 15 min after reperfusion. Group B received infusion of saline and served as control. The severity of myocardial injury was evaluated by epicardial ECG, hemodynamics, echo cardiographical asynergy area and left ventricular wall thickness, histopathological findings and magnitude of necrotic area. Group A demonstrated less injury than group B in most of the parameters. In particular, ratios of necrotic to perfused areas determined by dual fluorescence methods were significantly limited in group A (34.1 +/- 12.0 vs 66.0 +/- 11.3%), indirectly verifying that the O2- radicals play an important role in the genesis of ischema/reperfusion injury. In the second part of the study, the direct measurement of radicals in freeze-clamped myocardium was reported using electron spin resonance (ESR) spectroscopy. With this method, it was not possible to demonstrate the generation of O2-radicals in ischemic/reperfused myocardium. However, the data suggested that coenzyme Q10 anion radical, which exists in the normal myocardium, might provide an index of tissue injury.

Animals↗
PubMed1988

Effects of some psychotropic drugs on the b-wave of the electroretinogram in isolated rabbit retina.

The role of dopaminergic and cholinergic functions in the genesis of an electroretinogram is unclear. The present study was carried out to elucidate the direct actions of some psychotropic drugs in isolated rabbit retinas. Methamphetamine and apomorphine decreased dose-dependently the b-wave amplitude at a dose of 10(-7)-10(-5) g/ml. On the other hand, chlorpromazine and haloperidol, as well as atropine and amitriptyline, increased dose-dependently the b-wave amplitude at the same dose range. These data support the idea that dopaminergic and cholinergic systems play an important role in the genesis of the ERG.

Animals↗
PubMed1988

Comparative analysis of lymphocyte phenotypes between carriers of human immunodeficiency virus (HIV) and adult patients with primary immunodeficiency using two-color immunofluorescence flow cytometry.

A variety of phenotypic abnormalities of peripheral blood lymphocytes from 8 HIV-carriers (HIVC), 6 patients with common variable immunodeficiency disease (CVID), and 13 patients with selective immunoglobulin deficiency (SIgD) were compared using two-color flow cytometry. There was a close resemblance in phenotypic abnormalities between HIVC and the patients with CVID; i.e., increases in CD8+CD11-, Leu7+CD16- and CD3+DR+ cells, and decreases in CD4+Leu8+, CD4+Leu8-, Leu7+CD16+ and Leu7-CD16+ cells. The increase in CD3+DR+ cells was due to an increase in CD8+DR+ cells. The CD4/CD8 ratio was inverted in both groups. A strong correlation coefficient (CC) was found only between the CD4/CD8 ratio and CD4+Leu8+ cells in HIVC, while CC was also high between the CD4/CD8 ratio and CD8+CD11- cells in CVID. The phenotypic abnormalities of the patients with SIgD were various and no significant difference was found against the control, except for an increase in CD4+Leu8+ cells and a decrease in CD4+Leu8- cells, which suggests heterogeneity of immunological deficits in this group. In severe immunodeficiency, ineffective killer cells appeared to be induced as a result of an adaptive change involved in recurrent or persistent viral infections, and Leu8 molecule may be concerned in the susceptibility of CD4+ cells to HIV.

Acquired Immunodeficiency Syndrome↗
PubMed1988

A case-control study of lung cancer in nonsmoking women.

A case-control study of Japanese women in Nagoya was conducted to investigate the significance of passive smoking and other factors in relation to the etiology of female lung cancer. A total of 90 nonsmoking patients with primary lung cancer and their age- and hospital-matched female controls were asked to fill in a questionnaire in the hospital. Elevated relative risk (RR) of lung cancer was observed for passive smoking from mother (RR = 4.0; p less than 0.05) and from husband's father (RR = 3.2; p less than 0.05). No association was observed between the risk of lung cancer and smoking of husband or passive smoke exposure at work. Occupational exposure to iron or other metals also showed high risk (RR = 4.8; p less than 0.05). No appreciable differences in food intakes were observed between cases and controls.

Adult↗
PubMed1988

Nuclear deformity of hepatocytes in acute viral hepatitis.

Nuclear deformity of hepatocytes was measured using two parameters, the form factor and the axial ratio, in liver biopsy specimens from 29 patients with acute viral hepatitis (AVH). Another 13 patients with chronic persistent hepatitis (CPH) were added as control. Nuclear deformity of hepatocytes was morphometrically confirmed to increase in AVH compared to that in CPH. This was related to the regeneration of hepatocytes.

Acute Disease↗
PubMed1988

The presence of atrial natriuretic peptide in canine cerebrospinal fluid and its possible origin in the brain.

The presence of atrial natriuretic peptide (ANP) in canine cerebrospinal fluid (CSF) was clearly demonstrated and an attempt was made to determine its origin as either the brain or the atrium. The concentration of ANP in canine CSF was 0.78 +/- 0.37 pmol/l (n = 31) and showed no evident correlation with that in plasma (r = 0.12). Physiological doses of human alpha-ANP (alpha-hANP) were continuously infused intravenously into nine dogs, and ANP concentrations in CSF and plasma were examined six to eight times within a 120-min period following this. The ANP level in CSF was not influenced by the systemic administration of alpha-hANP up to 180 min. Only one low molecular weight peak corresponding to alpha-hANP could be obtained from the CSF samples, while both low and high molecular weight peaks were observed for plasma ANP by gel permeation chromatography. In the atrial and hypothalamic tissue extracts the same kinds of peaks were also evident. These results prove the presence of ANP in canine CSF and that it does not come from blood that has seeped across the blood-CSF barriers, but suggest that it may originate from the brain.

Animals↗