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T Saitoh

Publications and source records attributed to T Saitoh.

476 records · Page 27Linked to original sources

Localization of the histamine H(2) receptor, a target for antiulcer drugs, in gastric parietal cells.

BACKGROUND/AIMS: Histamine H(2) receptor antagonists are widely used for the treatment of peptic ulcer disorders. However, whether the H(2) receptor is present in parietal or immune cells in the lamina propria remains controversial. This study is designed to determine the H(2) receptor localization immunohistochemically using an antibody against the newly cloned mouse histamine H(2) receptor. METHODS: We cloned the mouse histamine H(2) receptor gene and generated a specific antipeptide antibody against the C terminus. Immunohistochemical studies were performed with this antibody and with a monoclonal antibody against H(+)/K(+) adenosine triphosphatase (ATPase). RESULTS: Histamine H(2) receptors were localized on the plasma membrane and on the cytoplasm just beneath the plasma membrane on the basolateral sides of gastric cells. Confocal microscopy of double-stained sections using the monoclonal antibody against H(+)/K(+) ATPase, a specific parietal cell marker, showed that histamine H(2) receptors colocalized with H(+)/K(+) ATPase. No specific histamine H(2) receptor immunoreactivities were observed in the submucosal regions. CONCLUSION: The H(2) receptor is localized in the gastric parietal cell.

Amino Acid Sequence↗

Clinical evaluation of CYFRA 21-1 in malignant pleural fluids.

The diagnostic value of the novel tumor marker CYFRA 21-1 in malignant pleural fluid was assessed in comparison to carcinoembryonic antigen (CEA). CYFRA 21-1 and CEA were measured in pleural fluid obtained from patients with 108 malignant and benign diseases. The levels of pleural fluid CYFRA 21-1 in malignant diseases (median: 84.5 ng/ml) were statistically higher than those in benign diseases (median: 13.9 ng/ml; p < 0.01). The CYFRA 21-1 test was able to discriminate significantly between squamous cell lung cancer and pneumonia (p < 0.01), while pleural fluid CEA levels could not. Receiver operating characteristic (ROC) curve analysis showed that the CYFRA 21-1 test has an advantage over CEA because of its higher specificity. These results indicate that measurement of CYFRA 21-1 in pleural fluid is a new tool, in addition to cytologic examination, to discriminate between malignant and benign diseases.

Adult↗

Suppressive effect of beta-carotene on the development of pulmonary foam cells in rats with hyper beta-lipoproteinemia.

The effect of beta-carotene (BC) on the development of pulmonary foam cells (PFCs) was studied in rats with diet-induced hyper beta-lipoproteinemia. Rats were fed a standard diet; a hyper-beta-lipoproteinemia diet (HB) consisting of the standard diet, 4% cholesterol, and 1% cholic acid; or the standard diet plus 0.1% BC; or the HB diet plus 0.1% BC diet (HBC). Rats in the HB and HBC groups developed hyper-beta-lipoproteinemia, but no significant differences were observed in serum levels of total cholesterol, phospholipid, and beta- lipoprotein (B-LP) between both groups. The percentages of foamy, lipid-ingested monocytes (FMs) to the number of blood monocytes (BMs), the number and size of lipid droplets in FMs, the percentages of PFCs to the number of alveolar macrophages from bronchopulmonary lavage fluid, and the score of PFC development in the lungs of rats in the HBC group were reduced compared to those of rats in the HB group. There were no differences in latex-phagocytotic activity of BMs among rats in the control, HB, BC, and HBC groups. BC suppressed the foamy transformation of BMs and development of PFCs deriving from the influx of FMs into the alveoli of hyper-beta-lipoproteinemic rats. Based on the present results, it is presumed that the antioxidative property of BC may prevent an oxidative modification of B-LP under the hyper-beta-lipoproteinemic condition, leading to a decrease in the uptake of oxidatively modified B-LP by BMs.

Animals↗

Carbon tetrachloride-induced hepatotoxicity enhances the development of pulmonary foam cells in rats fed a cholesterol-cholic acid diet.

The effect of CCl4-hepatotoxicity on the development of pulmonary foam cells (PFCs) was studied using 4 groups of rats. Rats in the control group were fed a standard diet; rats in the second group were fed a hyper beta-lipoproteinemic (HB) diet consisting of the standard diet, 4% cholesterol, and 1% cholic acid; rats in the third group were fed the standard diet and administered with CCl4 (1.0 ml/kg, i.p., fortnightly) (CT); and rats in the fourth group were fed the HB diet and administered with CCl4 (HT). At feeding week 10, rats in the HB and HT groups developed hyper beta-lipoproteinemia. The ratios of foamy, lipid-ingested monocytes (FMs) to blood monocytes (BMs) and the histologic scores of PFC development were significantly greater in the HB and HT groups than in the control and CT groups, respectively. The ratio of PFCs to alveolar macrophages from bronchopulmonary lavage fluid was significantly higher in the HT group than in the CT group. At feeding week 20, rats in the CT and HT groups suffered hepatic injury and hypo beta-lipoproteinemia. Despite hypo beta-lipoproteinemia, the FM and PFC development, the ratio of BMs in differential leukocyte counts, and latex-phagocytotic activity of BMs were enhanced in the HT group. Furthermore, markedly enlarged FMs, described here as giant-FMs, that contained numerous lipid droplets in their abundant cytoplasm appeared in the peripheral blood from rats in the HT group. Histologically, embolism caused by giant-FMs in the pulmonary blood vessels and intraalveolar accumulation of PFCs were detected with a high incidence in the HT group. The present study suggests that CCl4-hepatotoxicity may affect lipoprotein synthesis in the liver of hyper beta-lipoproteinemic rats and defective or modified lipoproteins can be phagocytosed actively by BMs, and then BMs transform into FMs or giant-FMs, resulting in the PFC development and pulmonary embolism by giant-FMs.

Animals↗

Rhabdomyosarcoma in a patient with mosaic Klinefelter syndrome and transformation of immature teratoma.

A 27-year-old man was found to have a mediastinal tumour and the histological diagnosis was immature teratoma. Remission was achieved by chemotherapy and total resection. However, he developed anaemia and leukoerythroblastosis after 2 years of remission, and was referred to our hospital. Rhabdomyosarcoma cells were detected in the bone marrow and pleural effusion. Moreover, karyotype analysis of peripheral blood and bone marrow cells revealed mosaic-type Klinefelter syndrome. We diagnosed the case as transformation of teratoma into rhabdomyosarcoma in Klinefelter syndrome. Although intensive chemotherapy was performed, the patient died with meningeal infiltration.

Adult↗

Ultrastructural abnormalities of bone marrow erythroblasts in refractory anemia.

Ultrastructural abnormalities of erythroblasts in 30 patients with refractory anemia (RA) according to FAB classification were studied. Nuclear clefts, iron-laden mitochondria, and myelin figures in cytoplasm were most frequently observed. Eleven patients (36.7%) with nuclear clefts of erythroblasts had a higher platelet count and higher incidence of cytogenetic abnormalities linked to poor prognosis than the patients without nuclear clefts. They also had a higher frequency of leukemic transformation and shorter survival than the patients without nuclear clefts. The nuclear clefts of erythroblasts, which are the result of impairment of DNA metabolism or nuclear formation and fusion during mitosis, may be one of the adverse prognostic factors for patients with RA.

Adolescent↗

Differential expression of protein kinase C isozymes in rat cerebellum.

Protein kinase C (PKC) is a family of enzymes found throughout the body, with the greatest diversity and concentration in brain tissue. To understand further the differential role of PKC isozymes in brain, we have raised antibodies against four PKC isoforms--alpha, beta I, beta II and gamma--using specific amino acid sequences predicted from cDNA sequences. On Western blot of rat cerebellar homogenate, these antibodies stained a band of Mr 80,000, a known molecular mass for PKC, except for anti-PKC(beta II), which stained an additional minor Mr 90,000 band. On rat cerebellar sections, specific sets of cells were stained by each antibody. In the molecular layer, stellate and basket cells were stained with anti-PKC(alpha) but not with anti-PKC(beta I), -(beta II), or -(gamma). Anti-PKC (alpha) and anti-PKC(beta II) seemed to stain the Bergmann glial fibre. In the Purkinje cell layer, Purkinje cells were stained with anti-PKC[beta I) and -(gamma). Anti-PKC (alpha) and -(beta II) were negative. Interestingly, a few Purkinje cells were not stained with anti-PKC(gamma). In the granule cell layer, both granule and Golgi cells were stained with anti-PKC(beta I) and -(beta II) but not with anti-PKC(alpha) or -(gamma). Glial cells were stained with anti-PKC(beta II) but not with anti-PKC(alpha), -(beta I), or -(gamma). This study suggests a differential distribution of PKC isoforms in different cells, irrespective of their neurotransmitters. The presence of both positive and negative staining of Purkinje cells with anti-PKC(gamma) raised the possibility of their heterogeneity.

Animals↗

Effects of prophylactic irradiation of acute lymphoblastic leukemia in the central nervous system of children.

The development of prophylactic therapy for acute lymphoblastic leukemia (ALL) in the central nervous system in children has resulted in an improvement of the prognosis and prolongation of patients' lives. On the other hand, late irradiation effects have increased with the improvement of the prognosis. Therefore, there is now an important need to lessen these late effects without deteriorating the prognosis. We have investigated the recurrence rate, the survival rate and the cause of death of ALL patients who were divided into a none prophylactic irradiation group and 15 Gy, 20 Gy and 24 Gy irradiation groups. The results show that the effect of prophylactic irradiation has been more effective in the 20 Gy group than that of the 24 Gy group. Furthermore, brain atrophy and leukoencephalopathy, which were investigated by X-ray CT in long-term survivors of post-prophylactic irradiation without recurrence, have been less in the 20 Gy group than in that of the 24 Gy group. This report presents the result that the most favorable dose for prophylactic irradiation for central nervous system leukemia of ALL in children is 20 Gy by a step-up method.

Atrophy↗