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Biomedical subjects

Y Shibata

Publications and source records attributed to Y Shibata.

At least 487 records · Page 27Linked to original sources
PubMed1992

Structural studies of peptidoglycans in Campylobacter species.

Peptidoglycans (PG) from Campylobacter coli, Campylobacter jejuni, and Campylobacter fetus were composed of muramic acid, glucosamine, alanine, glutamic acid, and diaminopimelic acid in a molar ratio of 1.1:1:1.7:1.1:09. Thirty percent of the amino groups of diaminopimelic acid were involved in cross-linkages between peptides. During cultivation, C. coli and C. jejuni changed from a spiral to a coccoid form. In C. coli, we could isolate PG only from the spiral forms in yields of 0.8-1.2% by dry weight. C. fetus did not change to a coccoid form, and always contained PG. Thus, it is possible that the morphological transformation from the spirals to the coccoid forms of C. coli and C. jejuni is accompanied by, and probably due to, the degradation of PG.

Campylobacter↗
PubMed1992

Comparative studies of three proteases of Porphyromonas gingivalis.

Three thiol-activated proteases, designated Qa, Ra, and Sa, in the soluble fraction of the cell extract of Porphyromonas gingivalis ATCC 33277 were purified by combinations of gel filtration, ion exchange chromatography and electrophoresis, and characterized. The molecular weights estimated by gel filtration method were 43 kDa (Sa), 87 kDa (Ra), and 170 kDa (Qa). However, they were found to have the same molecular weight (43 kDa), when estimated by SDS-PAGE, indicating that Sa is a monomeric, Ra is a dimeric and Qa is a tetrameric form. The 3 enzymes showed quite similar biochemical properties, and they could degrade not only the synthetic substrates but immunoglobulins, fibrinogen and albumin.

Bacterial Proteins↗
PubMed1992

Isolation and properties of the Capnocytophaga ochracea bacteriocin.

A bacteriocin from a subgingival plaque isolate of Capnocytophaga ochracea was purified and characterized. It was isolated from cell extract and had a molecular weight of 100,000. Streptococcus sanguis, Streptococcus mitis, Streptococcus mutans and Propionibacterium acnes were susceptible to the bacteriocin.

Actinomyces↗
PubMed1992

Protein p67. A calcium-binding protein localized at the sarcolemma of secretory atrial myocytes.

Bovine heart 67-kd protein (p67) was coisolated with calpactin I complex by cycles of Ca(2+)-dependent precipitation followed by solubilization with EGTA-containing buffer. Using affinity-purified anti-p67 antibody and anti-p36 (36-kd subunit of calpactin I) antibody, we examined the localization of the two proteins in secretory atrial myocytes and other endocrine tissues of adult rats. Immunofluorescence microscopy showed that p67 was expressed both in the atrial myocytes in situ and in cultured atrial myocytes in which we failed to detect p36 and that p67 appeared to be closely associated with the cell surface. We also found that p67 was colocalized with p36 in the thyroid follicle epithelium and zona reticularis of the adrenal gland. On the other hand, neither p67 nor p36 was detectable in pancreas islet cells. Immunoelectron microscopy revealed that p67 was localized at the sarcolemma in the atrial myocytes in situ. The p67, which was shown to be a globular molecule with a diameter of 18-25 nm by a low-angle rotary shadowing method, bound radioactive Ca2+ on a nitrocellulose membrane. The results suggest that Ca(2+)-binding proteins expressed in endocrine cells seem to vary from tissue to tissue and that p67 may function in Ca(2+)-mediated events at the plasma membrane of secretory atrial myocytes and some types of endocrine cells expressing this protein.

Amino Acids↗
PubMed1992

Light microscopic immunohistochemical analysis of the distribution of group II phospholipase A2 in human digestive organs.

The light microscopic and immunohistochemical distribution of human Group II phospholipase A2 (M-PLA2) in digestive organs of both human fetus and adult, with a new monoclonal antibody (MAb) against M-PLA2, was investigated semiquantitatively. The immunoreactivity was distributed similarly in the adult and fetal epithelium of the esophagus, duodenum, and small intestine, and in the acinar, islet, and duct cells of the pancreas. The epithelium of adult gallbladder was immunoreactive. Paneth cells, especially the secretory apparatus, were strongly immunoreactive. Hepatic Küpffer cells and macrophages of the adult spleen were also immunoreactive. These results suggest that these cells contain secretory-type Group II PLA2, which may be involved in host defensive mechanisms, such as phagocytosis in human digestive organs. In the adult colon, the immunoreactivity was observed only in the ascending colon and was not found in the transverse, descending, sigmoid, or rectal colon. The immunoreactivity was not found in fetal colon. Similarly, immunoreactivity was found in hepatocytes and Küpffer cells of adult liver but not in fetal liver. By contrast, strong immunoreactivity was observed in the epithelium of the fetal stomach but not in adult stomach except in gastric neck cells. This suggests that the expression of M-PLA2 may be related to cell differentiation in particular organs.

Adult↗
PubMed1992

Immunocytochemical localization of 67 KD Ca2+ binding protein (p67) in ventricular, skeletal, and smooth muscle cells.

By using immunocytochemical techniques, we examined the localization of a 67 kDa Ca2+ binding protein (p67) and calpactin I heavy chain (p36) in ventricular myocytes, skeletal myocytes, and intestinal smooth muscle cells. Immunofluorescence microscopy revealed that the p67 was expressed in all these muscle cells, whereas anti-p36 antibody stained cells in connective tissues but failed to stain these muscle cells. Immunogold electron microscopy was carried out to examine the subcellular localization of the p67 in muscle cells. The results showed that the p67 was exclusively confined to the plasma membrane of muscle cells and the presumptive transverse tubules of the striated myocytes. Immunoblot analysis with anti-p67 antibody showed that the p67 was indeed a constitutive protein of the sarcolemma isolated from rat hearts. These results indicate that the p67 is a sarcolemma-associated Ca2+ binding protein expressed in both striated myocytes and intestinal smooth muscle cells.

Animals↗
PubMed1992

Solubilization of limulus test reactive material(s) from Candida cells by murine phagocytes.

Solubilization of limulus test reactive materials from Candida was examined in the presence or absence of phagocytic cells. Solubilized limulus test reactive materials (LTRM) were detected in culture supernatant, and hot water and sodium hydroxide extracts of the acetone dried cells of Candida parapsilosis. Suspensions of Candida cells also reacted with limulus test, and LTRM were released from the acetone dried cells by serum treatment. After treatment of the acetone dried cells with polymorphonuclear leucocytes (PMN) or macrophages (M phi), a significant amount of LTRM was solubilized. Significant amounts of LTRM were also released by PMN during treatment of live and growing C. parapsilosis. The reactivity of LTRM was completely inhibited by the addition of excess amount of purified (1----3)-beta-D-glucan, suggesting LTRM from Candida cells as described above would contain (1----3)-beta-D-glucan. These results suggested that LTRM during fungal infection would come from the extracellular water soluble polysaccharide fraction as well as the insoluble cell wall fraction solubilized by the action of phagocytes.

Animals↗
PubMed1992

Effects of instilled fibrogenic particles on the clonal growth of murine pulmonary alveolar macrophages.

Murine pulmonary alveolar macrophages (PAM) form macrophage colonies in vitro with colony-stimulating factors, which stimulate the clonal growth of radioresistant alveolar colony-forming cells (AL-CFC). The toxic effects of fibrogenic mineral dust particles on AL-CFC were investigated after intratracheal instillation into mice. Exposure to either crocidolite asbestos or silica (Min-u-sil) induced a significant depletion of AL-CFC as well as a decrease in PAM recovery compared to either untreated or titanium dioxide-exposed animals. Such effects were also noted with different doses (50-200 micrograms/animal) of instilled particles. The plating efficiency of AL-CFC was depleted in PAM exposed to fibrogenic particles in vitro, but not when exposed to nonfibrogenic titanium dioxide particles. These results indicate the toxic effects of fibrogenic dust particles on the clonal growth of PAM, cells which play a role in the clearance of inhaled particles from the lung and in subsequent pathologic processes.

Animals↗
PubMed1992

Malignant lymphoma of the central nervous system presenting with central neurogenic hyperventilation. Case report.

The case is described of a 72-year-old woman who presented with a progressive right hemiparesis and central neurogenic hyperventilation. Pathological and radiological studies revealed diffuse infiltration of a malignant lymphoma into the entire central nervous system and the upper spinal cord. The authors review 12 cases of tumor-induced central neurogenic hyperventilation and discuss the pathophysiology of this condition.

Aged↗
PubMed1992

[Echocardiographic assessment of aortic regurgitation and aortic root dilatation in bicuspid aortic valve].

Aortic regurgitation (AR) and aortic root dilatation in 29 consecutive patients with bicuspid aortic valves but without aortic root disease (20 males, and 9 females: aged 27-85 years) were studied using two-dimensional echocardiography. The normal ranges of aortic root dimensions were calculated from values of 185 normal subjects, as 95% confidence intervals. AR was observed in 17 patients by color flow mapping. In 12 of the 17 AR patients, no significant lesion of the aortic cusp was detected by two-dimensional echocardiography. These 12 AR patients were compared with 12 patients without AR. Increase in dimension of the aortic root was relatively frequent in the 12 AR patients at the aortic annulus (AA) (67 vs 17%, p < 0.05), and at the sinus of Valsalva (A1) (67 vs 17%, p < 0.05). At the ascending aorta 5 mm distal to the sinus of Valsalva (A2), the difference was not significant (58 vs 17%, p < 0.09). The 12 bicuspid AR patients without significant lesions of the aortic cusp were compared with 41 AR patients with normal tricuspid aortic valves. The frequencies of cases with increased aortic root dimension were 67 vs 46% (ns) at the AA, 67 vs 22% (p < 0.05) at A1 and 58 vs 5% at A2 (p < 0.01). Thus, aortic annular dilatation was thought to be the cause of AR in bicuspid and tricuspid aortic valves without significant lesions of the aortic cusps, and generalized dilatation of the aortic root was more frequent in bicuspid AR patients than in tricuspid AR patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Pure yolk sac tumor of the testis with brain metastasis: report of an adult case].

Herein we report an adult case of pure yolk sac tumor with brain metastasis. The patient was a 37-year-old male who presented with indulation of his left scrotum for 10 months. The plain computerized tomographic (CT) scan on entry demonstrated tumor metastasis to his lung and liver and serum alpha-fetoprotein (AFP) level was 786 ng/ml. Five days after admission, he developed hemiplegia secondary to the cerebral metastasis and hemorrhage. After chemotherapy and operation of right-posterior lobectomy, PVB (cisplatinum, vinblastine, bleomycin) chemotherapy produced a complete remission and the elevated serum AFP was normalized. However, the second course of chemotherapy had to be discontinued because of drug-induced hepatitis. He died of massive tumor metastasis to his brain 6 months after craniotomy.

Adult↗
PubMed1992

[Analysis of the determinant factors for open heart surgery without blood transfusion by the quantification theory--possibility of application of maximum surgical blood order schedule for open heart surgery].

In order to complete operations without blood transfusion we have chosen means of preoperative autologous blood saving and intraoperative autotransfusion, but we have not always achieved our purpose. We examined 29 patients (13 patients without blood transfusion and 16 with blood transfusion) to analyze the determinant factors as to whether open heart surgery without blood transfusion may be indicated or not, according to the quantification theory (type II) and to examine the possibility to apply the maximum surgical blood order schedule (MSBOS) for the open heart surgery by the quantification theory (type I). The analysis of determinant factors revealed hematocrit (Ht) value before saving of blood (more than 40%) as the best contributor of possibility of non-blood transfusion surgery, followed by the amount of blood loss during operation (less than 600 ml), the amount of saving blood (more than 800 ml), body weight (less than 70 kg), calculated Ht value on the beginning of cardiopulmonary bypass (CPB) (more than 24%), CPB time (less than 120 minutes) and the amount of postoperative blood loss (less than 600 ml). The prospective using blood volume at the operation was precisely calculated by the values of 4 preoperative factors, that is, the amount of saving blood, calculated Ht value on the beginning of CPB, CPB time and body weight. Therefore it is important to increase the amount of preoperative saving blood and decrease the amount of surgical bleeding in order to perform operations without blood transfusion, and is possible to apply the MSBOS for the open heart surgery.

Adolescent↗
PubMed1992

Clinical characteristics of chronic cutaneous graft-versus-host disease in Japanese leukemia patients after bone marrow transplantation: low incidence and mild manifestations of skin lesions.

We investigated the incidence of chronic graft-versus-host disease (GVHD) and skin and oral lesions in chronic GVHD in 90 Japanese leukemia patients surviving over 100 days after bone marrow transplantation (BMT) from HLA-compatible siblings. The clinical characteristics of chronic cutaneous GVHD occurring in eight of these patients are summarized. There were some differences from previous reports in the USA and Europe. The incidence (8/29: 28%) of skin lesions in chronic GVHD was low in contrast to the previously reported high incidence (79-90%). Cutaneous manifestations in six out of eight patients with chronic GVHD tended to be mild, and lichen-planus-like eruptions in the skin and scleroderma-like lesions, which are well known as representative cutaneous manifestations of chronic GVHD, were rare. Furthermore, our statistical analysis indicated that there was no relationship between pretransplant total body irradiation and GVHD prophylaxis or acute GVHD and the onset of chronic cutaneous GVHD. The present study suggests that the differences from previous reports in the USA and Europe concerning chronic cutaneous GVHD may be attributable to differing genetic backgrounds in Japanese and western populations.

Acute Disease↗
PubMed1992

Heparin stimulates the collagen synthesis in mineralized cultures of the osteoblast-like cell line, MC3T3-E1.

We found that heparin induced an increase in collagen synthesis in MC3T3-E1 cells cultured for 15 and 30 days. Northern blots showed that the effect of heparin on the collagen synthesis was mediated through the mRNA expression of type I collagen (day 15). Although heparin stimulated collagen synthesis over and above that stimulated by the transforming growth factor (TGF)-beta, heparin did not stimulate TGF-beta binding. This study indicates that heparin has special tasks both in bone formation and resorption, since it has the ability to form and degrade collagen. We suggest that heparin assists the regulation of collagen metabolism at bone resorption sites.

Animals↗
PubMed1992

[Clinical study of correlation pre-senile, senile depressive state with silent cerebral infarction--MRI findings and its distribution].

We examined the relationship between the pre-senile/senile depressive state and silent cerebral infarction using MRI. The subjects studied were 56 patients 50 years of age or older with a depressive state who underwent MRI and who were hospitalized and treated at the Department of Psychiatry or the Department of Neurology of Hiroshima Prefectural Hospital. We made a diagnosis of depression in patients who fulfilled the criteria of DSM-III-R for major depression. Patients in whom apoplectic attacks had occurred, or who had local neurologic symptoms or a history of evident cerebrovascular disorders, were not included in the study. Silent cerebral infarction was observed with pre-senile onset in 60.3% of patients with a pre-senile depressive state, and the complication rate was significantly higher than for cases with juvenile onset (20%). For patients with a senile depressive state, the complication of silent cerebral infarction was found in 53.6% of cases of pre-senile onset and in 100% of cases of senile onset. These rates were remarkably higher than the age-related complication rate of silent cerebral infarction in normal persons reported hitherto, we therefore suspect that nearly half of patients with depressive state of pre-senile onset and most of patients with that of senile onset might have an organic-depressive state complicated by silent cerebral infarction. Both perforating-type infarcts and cortical-type infarcts were found, suggesting that infarct-related foci of depressive states were polyphyletic. When we divided the depressive states complicated by cerebral infarction into 2 subtypes, those complicated by a perforating-type infarct and those by a cortical-type infarct, and compared the 2 types, we found possible differences in clinical symptoms and course between the subtypes. These differences seem worthy of further study. Among cortical-type lesions, parietal lesions were predominant, followed by frontal and then temporal lesions in incidence. There were significantly more left frontal lesions than right frontal lesions. Infarcts of both the parietal lobe and left frontal lobe may be related to the depressive state. Compared with cases not complicated by cerebral infarction, those with perforating- and mixed-type cerebral infarction were complicated with PVH significantly more frequently, similarity in risk factors and pathology between perforating-type cerebral infarction and PVH was suggested by these results.

Age Factors↗
PubMed1992

Postoperative chemotherapy and follow-up program in colon cancer with high serum CEA level.

We present a patient with colon cancer who had a high serum CEA level without detectable liver metastases at surgery. He underwent hepatic arterial infusional chemotherapy for suspicious liver metastasis concomitant with colon resection at the initial operation. He was followed closely by monitoring the serum CEA levels as well as abdominal US and CT. Five months after the first operation, a small but apparent metastatic lesion was detected in the liver, for which curative resection was performed. The importance of postoperative management with chemotherapy for occult metastases in the liver and close follow-up by CEA monitoring is discussed for such a patient.

Adenocarcinoma↗