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S Tashiro

Publications and source records attributed to S Tashiro.

At least 55 records · Page 3Linked to original sources
PubMed1998

Decrease of nuclear protein phosphatase 1 activity and induction of mitotic arrest and apoptosis by a marine microalgal polysaccharide in human myeloid leukemia U937 cells.

An extracellular polysaccharide, which we designate GA3P, produced from a marine microalga dinoflagellate Gymnodinium sp. A3, has been previously reported to induce apoptosis in lymphoid and myeloid cell lines. We found that the GA3P accumulates cells into the mitotic phase of the cell cycle and decreases nuclear protein phosphatase 1 (PP1) activity in a dose-dependent manner in myeloid leukemia U937 cells. Dose-dependent patterns in the decrease of nuclear PP1 activity and in the accumulation of cells into mitotic phase or apoptotic status by the GA3P were concordant with each other, indicating that the decrease of nuclear PP1 activity at least mediates some of the etiological steps in development of mitotic arrest and apoptosis induced by the GA3P. In addition, the GA3P repressed the expression of protein levels of the PP1 catalytic subunit isoform PP1 gamma 1 gamma 1. We thus suggest that the decrease of nuclear PP1 activity is due to down-regulation of the protein levels of the PP1 gamma 1.

Animals↗
PubMed1998

Can the liver with Gilbert's syndrome be used as graft of living-related liver transplantation?

Gilbert's syndrome is the common cause of non hemolytic unconjugated hyperbilirubinemia with a prevalance of 3-7%. Gilbert's syndrome may introduce a selection of potential liver donors from brain death patients. We present a case of living-related liver transplantation (LRLT) from a donor with Gilbert's syndrome. A 22-year-old woman had been diagnosed as having liver cirrhosis at the age of 5. She underwent liver transplantation with the donor's left lobe as the graft. The donor, who was the father of the patient, had been diagnosed with Gilbert's syndrome. Although the recipient was well until 11 months after surgery, she died of subacute fulminant hepatitis 16 months after surgery. However, it was clear that the liver with Gilbert's syndrome could be used as a graft of living-related liver transplantation for adult recipients.

Adult↗
PubMed1998

Assessment of the biological malignancy of hepatocellular carcinoma: relationship to clinicopathological factors and prognosis.

It is difficult to determine the prognosis of patients with hepatocellular carcinoma (HCC). Assessment of the clinicopathological and biological malignancy of HCC may help in determining treatment strategies and predicting outcome. The tumor DNA content, p53 protein expression, proliferating cell nuclear antigen labeling index, and argyrophilic proteins of nuclear organizer regions were used as markers of biological malignancy. A correlation between these biological parameters and clinicopathological factors was sought. DNA aneuploidy was observed in 31 of 80 tumors (38.8%). Aneuploidy increased as differentiation decreased. The overall survival rate of patients with aneuploid tumors was significantly poorer than that of patients with diploid tumors. p53 overexpression was observed in 18 of 80 tumors (22.5%). The incidence of p53 positivity increased significantly with increasing tumor size and poorer differentiation. The overall survival rate of p53-positive patients was significantly worse than that of p53-negative patients. The proliferating cell nuclear antigen labeling index and the mean number of argyrophilic proteins of nuclear organizer regions were higher in more poorly differentiated lesions. We conclude that DNA ploidy and p53 expression are useful prognostic indicators in HCC. Cell proliferation increases as HCC progresses. With progression, tumors tend to become more poorly differentiated.

Adult↗
PubMed1998

Prognostic significance of Ki-67 and p53 antigen expression in carcinomas of bile duct and gallbladder.

Ki-67 and p53 protein expression was evaluated immunohistochemically in 32 patients with intrahepatic, extrahepatic bile duct and gallbladder carcinomas, who underwent surgery at First Department of Surgery, The University of Tokushima School of Medicine. p53 expression was found more in the well differentiated group than poorly differentiated group (p = 0.007). MIB1 labelling index (MIB1 LI) was higher in EHC than in GBC (p = 0.0061). MIB1 LI (T), (MIB1 LI in tumor) was higher in cases with lymph node metastasis than in those without lymph node metastasis (p = 0.0189). Moreover, MIB1 LI (L) (MIB1 LI in metastasized lymph node) was higher in poorly differentiated than in well differentiated carcinoma (p = 0.0404). Prognostically, patients with high MIB1 LI (T) (> 56.93) had a worse prognosis after surgery than those with low MIB1 LI (T) (p < 0.05). There was no association between p53 positive tumors and MIB1 expression. These results suggest that cancer cell proliferative activity was markedly increased in cases with EHC compared to those with GBC and the poorly differentiated and lymph node metastasis group. MIB1 LI in tumor was found to be a good prognostic indicator whereas there was no association of p53 positive tumor with MIB1 expression and prognosis of the patients.

Adult↗
PubMed1998

[Standard radical surgery for carcinoma of the gallbladder invading the subserosal layer (ss cancer)].

The postoperative survival rate is dependent on the invasive depth of cancer of the gallbladder, as shown in in our studies and in other Japanese studies detailed in questionnaires. In cases of m, mp cancer, good survival rates are achieved after simple cholecystectomy or wedge resection of the liver including the gallbladder bed with regional lymphadenectomy. However, when the cancer has invaded beyond the subserosal layer, lymph node and adjacent organ involvement is found in a large number of patients, and long-term survival cannot be achieved by wedge resection of the liver with dissection of the cystic nodes and pericholedochal lymph nodes. The poor prognosis of patients with these lesions might be due to the use of inappropriate surgical procedures. When the appropriate procedures based on the extent of subserosal (ss) invasiveness of gallbladder cancer were used, long-term survival was obtained in our patient series. The appropriate radical surgical procedures for ss cancer are as follows: When cancer is diagnosed as invading to the ss layer by intraoperative ultrasonography (IOUS), wedge resection of the liver including the gallbladder bed and D2 dissection of the lymph nodes including the paraaortic lymph nodes (16a2 inter, 16b1 inter pre) should be performed. When liver involvement (Hinf1-Hinf2) is diagnosed by IOUS or cancer is located on the liver bed, resection of segment 4a 5 in Couinaud's classification is performed. When there is involvement of the pericholedochal nodes, nodes around the common hepatic artery, and/or posterior pancreatoduodenal nodes are found at operation, pancreatoduodenectomy should be performed. Wedge resection of the liver or S4a 5 segmental resection of the liver with resection of the bile duct and D2 dissection of the lymph nodes including the paraaortic lymph nodes is considered to be the standard radical operation for many patients with ss cancer of the gallbladder.

Gallbladder Neoplasms↗
PubMed1997

Acetaminophen absorption test as a marker of small bowel transplant rejection.

We recently evaluated the acetaminophen absorption test as a marker of graft rejection for small bowel transplantation(SBTX). Randomly bred male Wistar rats were used as recipients and donors. Rats (n=45) received heterotopic small intestinal transplants and were divided into three groups (n=15 for each group). In group A, a 10-cm segment of jejunum of was exteriorized as a Thiry-Vella loop. In group B, immunosuppression was not given after SBTX. In group C, rats were treated with FK506 after SBTX (0.3 mg/kg body weight, 0-6 postoperative days). Serum acetaminophen concentrations were measured 15 min after instillation of 0.15 g/kg acetaminophen into the intestinal loop on postoperative days 1, 3, and 7 (n=5 for each group). Blood flow and histology of the graft were also evaluated. In the SBTX group only, the grafts showed the histological change after acute rejection. On day 3, plasma acetaminophen concentrations in this group showed a significant decrease, which correlated with the mild histological changes of graft rejection. Graft blood flow of the SBTX group decreased significantly on day 7, following the severe graft destruction of advanced rejection. No remarkable changes were observed in the other two groups. The acetaminophen absorption test appears to be useful for the early detection of SBTX graft rejection.

Absorption↗
PubMed1997

Ultrasonographic evaluation of gastric emptying in normal children and children after pyloromyotomy.

Gastric emptying in the fundus, body, and antrum of the stomach was evaluated by ultrasonography (US) in 41 control children aged 2 to 18 years and 30 patients aged 1 to 19 years who had undergone pyloromyotomy because of hypertrophic pyloric stenosis. The gastric emptying curve decreased in an exponential manner for both control children and patients, while there was no significant difference in gastric emptying time (GET) between control children and patients within any of the age groups. However, GET was faster for younger children in both groups. An X-ray contrast study of the stomach performed in 2 patients who showed markedly delayed GET showed delayed gastric emptying but no significant deformities of the prepylorus. Our results suggest that US is a reliable method of measuring GET in children.

Adolescent↗
PubMed1997

Isolation and immunochemical characterization of heparan sulfate rich proteoglycan (HSPG) present in the basement membrane of human placenta.

We isolated and characterized heparan sulfate rich proteoglycan (HSPG) present in the basement membrane from 7 M urea insoluble materials of the human placenta by CsCl isopycnic centrifugation, anion-exchange chromatography and gel filtration. The molecular mass of the glycosaminoglycan chain from pronase digestion of HSPG was estimated to be 30-100 kDa. The reported glycosaminoglycan moiety of proteoglycans from the lens capsule, glomerular basement membrane and fibroblast consists only of the heparan sulfate chain. However, the glycosaminoglycan of the proteoglycan isolated from human placenta was composed of heparan sulfate (82%) and other glycosaminoglycans (18%). An affinity-purified rat antibody against HSPG specifically reacted with HSPG, but it did not immunoreact with basement membrane components such as laminin and type IV collagen. Indirect immunohistochemical observations of tissue HSPG revealed staining mostly along with basement membrane (basal layer). From these results, isolated HSPG from human placenta appeared to be a constituent of the basement membrane, together with other basement membrane components such as type IV collagen, laminin and nidogen.

Basement Membrane↗
PubMed1997

Nuclear proteins binding to the recombination hotspot region of the retinoic acid receptor alpha gene.

Acute promyelocytic leukemia (APL) has been characterized by 15;17 chromosomal translocation, which involves the retinoic acid receptor alpha (RARA) gene on chromosome 17 and the PML gene on chromosome 15. An extremely restricted region (ERR) of 50 bps within the second intron of the RARA gene was identified as the cluster region of breakpoints by sequencing analyses. ERR was tested by in vitro transfection-recombination assay, and was shown to be the recombination hot spot. In this study, presence of DNA binding proteins to the 148 bps DNA fragment which contains ERR was confirmed by gel-mobility shift analysis in the nuclear extract of NIH3T3 cells and human leukemia cell lines. Furthermore, in vitro study with the mouse sarcoma cell lines using the recombination reporter plasmid containing ERR showed that ERR might be involved in the homologous recombination in addition to the illegitimate recombination. The DNA binding proteins specific to ERR might play an important role in chromosome translocation.

3T3 Cells↗
PubMed1997

[Secondary hepatic resections in a case of sigmoid colon cancer with multiple liver metastasis (H3) after successful continuous hepatic artery infusion chemotherapy oriented by in vitro chemosensitivity test].

A 43-year-old woman was admitted to our hospital for sigmoid colon cancer with multiple liver metastasis (H3). As preoperative CTAP (CT during arterial portography) examination showed 23 metastatic nodules in the whole liver, hepatic resections were not indicated. Angiographic findings showed that right and left hepatic arteries branched separately from the celiac artery. Sigmoid colon resection with D3 lymph node dissection and catheterization to the right hepatic artery via gastroduodenal artery were undertaken as a first operation. Continuous hepatic artery infusion chemotherapy with MMC, 5-FU oriented by in vitro chemosensitivity test (SDI test: Succinic Dehydrogenase Inhibition test) of primary tumor was performed 7 days after the first operation. After administration of MMC (40 mg) and 5-FU (16,500 mg), metastatic nodules in the right lobe almost disappeared except for the one tumor of S7, but the size and number of the nodules in the left lobes increased. At 10 months after the first operation, the left hepatic lobectomy and extirpation of only one tumor in the right lobe (S7) underwent. This case showed the usefulness of continuous hepatic artery infusion chemotherapy oriented by in vitro chemosensitivity test for multiple liver metastasis from colon cancer.

Adenocarcinoma↗
PubMed1997

Bile-induced DNA strand breaks and biochemical analysis of bile acids in an experimental model of anomalous arrangement of the pancreaticobiliary ducts.

A canine experimental model for the anomalous arrangement of the pancreaticobiliary ducts (APBD) was made to investigate the effects of bile acids on carcinogenesis. Seven adult mongrel dogs underwent dorsal pancreatico-cholecystostomy to serve as a functional model for APBD, and six dogs underwent the same procedure with the pancreatic duct ligated as a control group. Bile from the gallbladder was taken 14 months after surgery for bile acid analysis by HPLC. DNA strand breaks in HeLa cells induced by the bile were also investigated in situ by nick translation method. As a result, the fraction of cholic acid tended to be lower, and that of deoxycholic acid slightly higher in APBD-dogs (N.S.). The ursodeoxycholic acid percentage in APBD-dogs significantly decreased compared with that in the control and normal dogs (p < 0.05). Extremely high frequency of DNA strand breaks was shown in only two out of seven APBD-dogs. In those two dogs, the cholic acid percentage decreased and that of deoxycholic acid increased extremely. These findings suggest that the alteration of the bile composition in APBD caused frequent DNA strand breaks and repair which might lead to gene mutation and biliary tract carcinoma.

Animals↗
PubMed1996

S phase specific formation of the human Rad51 protein nuclear foci in lymphocytes.

The Rad51 protein, which is a homologue of the bacterial RecA protein, is involved in mitotic and meiotic recombination and in repair of double-strand breaks of DNA in yeast. The Rad51 homologue is conserved from yeast to human. In this study, the Rad51 protein was shown to be induced in peripheral blood lymphocytes (PBLs) 36 h after phytohemagglutinin (PHA) stimulation. Immunofluorescence study revealed that the distribution of the Rad51 protein in the nucleus was not uniform and focus-like staining was observed. Formation of the Rad51 foci was induced at 36 h after treatment of the cells with PHA. Twenty five percent of the cells had the foci at this time and the number of cells with foci declined thereafter. Cell cycle study using laser microscope by double staining method suggested that the appearance of the Rad51 nuclear foci was S phase specific. Furthermore, double staining study for the Rad51 protein and incorporated BrdU confirmed S phase specific appearance of the Rad51 nuclear foci. Formation of the Rad51 nuclear foci in PHA-stimulated lymphocytes might be involved in DNA recombination or DNA repair in S phase. The roles of RAD51 foci in S-phase will be discussed.

Cell Nucleus↗
PubMed1996

Detection of different quasispecies of hepatitis C virus core region in cancerous and noncancerous lesions.

The quasispecies of hepatitis C virus (HCV) core region in non-cancerous and cancerous hepatocellular carcinoma (HCC) lesions, respectively, of 7 patients with hepatocellular carcinoma were studied. Multiple fluorescence based-polymerase chain reaction (PCR)-single strand conformation polymorphism exhibited a different set and a larger number of quasispecies in cancerous portions than those in non-cancerous portions. DNA sequencing of PCR-amplified core region substantiated an accumulation of nucleotide substitutions, and a greater number of quasispecies in cancerous portions than those in non-cancerous portions. The deduced amino acid sequences disclosed that at the peptide position 45, Ser is dominant in non-cancerous lesions, and Gly in cancerous lesions, respectively. Thus, HCV in hepatocellular carcinoma includes a large number of specific quasispecies presumably due to their vigorous proliferation. A different set of quasispecies with the amino acid change is presumed to be related to the hepatocarcinogenesis.

Aged↗
PubMed1996

Effects of biliary obstruction on the endocytic activity in hepatocyte and liver sinusoidal endothelial cells in rats.

Obstructive jaundice impairs function in liver parenchymal and sinusoidal cells. In this study, the endocytic activity in sinusoidal endothelial cells in the rats with biliary obstruction was measured by plasma clearance of radiolabeled formaldehyde-treated bovine serum albumin. The endocytic activity in hepatocytes was also measured with asialofetuin. The clearance of asialofetuin significantly decreased after 1 week of biliary obstruction and the clearance was reduced to 42% of the controls at 4 weeks. In contrast, the clearance of formaldehyde-treated bovine serum albumin was essentially unchanged until 4 weeks of biliary obstruction. The maximal removal rate which was assessed by kinetic analysis of injected protein for formaldehyde-treated bovine serum albumin showed no significant decrease at 2 weeks compared with the controls, while that for asialofetuin was significantly decreased to 50% of the controls. These results suggest that the endocytosis of formaldehyde-treated bovine serum albumin in endothelial cells is maintained until the advanced stage of biliary obstruction, whereas the endocytic activity for asialofetuin in hepatocytes is impaired earlier.

Animals↗
PubMed1996

Purification of a noncollagenous high molecular weight protein from bovine articular cartilage.

A noncollagenous high molecular weight protein (HMW) was isolated from bovine articular cartilage by CsCl density gradient centrifugation followed by DEAE-cellulose chromatography and gel filtration chromatography. The molecular weight was estimated to be 320 kDa and the reduced HMW had a molecular weight of 105 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The amino acid composition of HMW showed a high content of aspartic acid, but no hydroxylysine and hydroxyproline were detected, indicating that the protein was not a collagen. Affinity purified rabbit antibody against HMW reacted specifically with HMW, but there was no immunoreaction with cartilage-specific proteoglycan, type II collagen and type I collagen. HMW showed dose-dependent attachment to types I, II, III and V collagens. However, HMW did not bind to fibronectin, decorin and heparin. Furthermore, the binding of HMW to heat-denatured collagens was lower than native collagens. In these observation, HMW may be recognized the triple helix structure of collagen for the interaction.

Animals↗
PubMed1996

[Studies on the bioactive constituents of Aurantii Fructus Immaturus].

An ethanol extract of "Kijitsu" (Aurantii Fructus Immaturus, Citrus aurantium L.) collected in China was assessed for the antitumor activity using murine leukemia P388 in vivo, and the extract was found to be active by the antitumor bioassay in vivo and in vitro. The extract was separated into a petroleum ether-soluble fraction and an ethyl acetate-soluble fraction. Fractionation was carried out using an index of cell-growth inhibitory activity against mouse leukemia L1210 cells to isolate antitumor active substances or compounds. The active compounds were purified employing silica gel column chromatography and HPLC. The antitumor effect of the isolated active compounds was studied. Five compounds, auraptene, marmin, tangeretin, nobiretin and 5-[(6',7'-dihydroxy-3',7'-dimethyl-2-octenyl)oxy]psoralen were isolated from Citrus aurantium L. Though they are all known compounds, 5-(6',7'-dihydroxy-3',7-dimethyl-2-octenyl)oxy-psoralen from this plants was first isolated. These compounds showed a cell-growth inhibitory effect against L1210 and K562 in vitro.

Animals↗