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S Arii

Publications and source records attributed to S Arii.

119 records · Page 7Linked to original sources
PubMed1983

Minimal requirement of the remnant pancreas for protein and DNA synthesis of cultured hepatocytes prepared from pancreatectomized rats.

The incorporation of 3H-thymidine and 3H-leucine into the hepatocytes was studied, using cultured hepatocytes prepared from normal and pancreatectomized rats. (1) In the cultured hepatocytes prepared from 80% pancreatectomized rats, the incorporation of 3H-thymidine and 3H-leucine into hepatocytes remained unchanged compared with those of sham-operated controls. In contrast, in those from totally pancreatectomized rats, the incorporation of 3H-thymidine and 3H-leucine decreased to approximately 67% and 37% respectively of sham-operated controls. However, those returned to near normal in the cultured hepatocytes from totally pancreatectomized rats treated by 0.8 IU/kg of insulin. (2) The addition of insulin (10(-4) M) to the culture medium stimulated the incorporation of 3H-thymidine into cultured hepatocytes prepared from normal rats to 148% of controls. The insulin-stimulated incorporation was inhibited by the addition of glucagon to the culture medium. The combined addition of insulin and glucagon did not synergistically act on DNA synthesis. It is suggested that the portal blood insulin in the presence of more than 20% of the pancreas is imperative for maintaining spontaneous regeneration.

Animals↗
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Registries in Japan: current status of hepatocellular carcinoma in Japan. Liver Cancer Study Group of Japan.

The Liver Cancer Study Group of Japan registered 11,379 patients with hepatocellular carcinoma (HCC) diagnosed from January 1, 1990 to December 31, 1991 in 536 hospitals throughout the country. This nationwide survey revealed the current status of HCC in Japan regarding the epidemiology, clinical characteristics, histopathological features, diagnosis, surgical and conservative treatments, and the outcome. The survival rates of the HCC patients who received hepatic resection, transarterial embolization (TAE), and percutaneous ethanol injection (PEI) were also calculated based on follow-up from January 1, 1987 to December 31, 1991. Three-year and 5-year survival rates of the patients who underwent hepatic resection were 57.5% and 40.8%, respectively, and those of TAE were 19.5% and 8.0%, respectively. Three-year survival rate of the patients with PEI was 53.2%. Cox's multivariate analysis showed that significant prognostic variables after partial hepatectomy were serum alpha-fetoprotein level, tumor size, number of tumors, associated liver cirrhosis, age, surgical curability, and portal involvement.

Adolescent↗
PubMedDate not supplied

Augmented local immunity in the liver by a streptococcal preparation, OK432, related to antitumor activity of hepatic macrophages.

The aim of this study was to investigate the augmentative effect of a streptococcal preparation, OK432, on the immunological competence of hepatic macrophages. We found that OK432 was distributed predominantly to hepatic macrophages after intravenous injection, and Northern blot analysis revealed that OK432 induced the gene expression of IL-1 alpha, beta, and TNF alpha in the liver. The induction of mRNAs was evident 1 h after the intravenous injection of OK432 and their accumulation reached a maximal level at 3 h. TNF production of hepatic macrophages was also increased by the intravenous injection of OK432. Furthermore, OK432 significantly increased the proportion of IL-2 receptor-positive hepatic macrophages. As for antitumor activity in the liver being augmented by OK432, the cytotoxic and cytostatic activity of hepatic macrophages from OK432-treated rats against tumor cells was significantly increased and OK432 markedly reduced the number of tumor nodules in the liver after the inoculation of tumor cells via the portal vein. These findings, which indicate that OK432 has various immuno-stimulating actions on hepatic macrophages, leading to the augmentation of antitumor activity in the liver, suggest that OK432 may be of some benefit in helping to prevent hepatic metastasis, at least in part, via its activation of hepatic macrophages.

Animals↗
PubMedDate not supplied

Beneficial effect of tetrahydrobiopterin on the survival of rats exposed to hepatic ischemia-reperfusion injury.

INTRODUCTION: The protective role of nitric oxide (NO) against hepatic ischemia-reperfusion (I/R) injury remains controversial. In this study we investigated the effect of tetrahydrobiopterin (BH4) on the survival of rats exposed to an hepatic I/R injury. METHODS: The rats were subjected to 100 minutes of 70% hepatic ischemia 30 minutes after administration of BH4 or saline. A specific inducible NO synthase (iNOS) blocker, 1400W, was used to evaluate endogenous iNOS. NOS protein measured the histological appearance of the liver by Western blotting, and survival was evaluated after reperfusion. RESULTS: The 1-week survival rate was 60% among the BH4 group and 10% for the saline group. The serum ALT and bilirubin values in the BH4 group were significantly lower than the saline group. Histological examination of the liver revealed only a small necrotic area in the BH4 group as opposed to massive necrosis and cell infiltration in the saline group. Injection of 1400W significantly decreased the prolongation of survival produced by BH4. CONCLUSIONS: BH4 significantly improved the survival rate, the histological findings, and the liver function, thereby reducing liver failure. Western blotting showed a higher level of iNOS protein in the BH4 group than the saline group, 1400W suppressed this effect of BH4. Taken together, these observations suggest that NO derived from reactions driven by BH4-induced iNOS exerts a protective effect against reperfusion injury.

Animals↗
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Teratoma formation and hepatocyte differentiation in mouse liver transplanted with mouse embryonic stem cell-derived embryoid bodies.

We previously reported that mouse embryonic stem (ES) cells are capable of differentiating into hepatocytes in cultured embryoid bodies (EBs) and that hepatocytes generate in the recipient liver injected with cultured day-9 EB cells via spleen without the formation of a teratoma. Because ES cells frequently form teratomas in recipient mice, we investigated incidence of teratoma formation when day-9 EBs derived from ES cells were transplanted directly into the subcapsule of mouse liver. In contrast to injection of day-9 EB cells through the portal vein via the spleen, direct subcapsular injection of cultured day-9 EB cells into liver, and even of cultured day-15 EBs, resulted in an high incidence of teratoma in the liver. In teratomas of livers injected directly with day-15 EBs, hepatocytes were detected singly and in clusters. These results imply that undifferentiated cells capable of developing into teratomas exist in cultured EBs, and even in cultured day-15 EBs containing differentiated hepatocytes.

Animals↗
PubMedDate not supplied

Studies on the most efficient vector systems for gene transduction into dendritic cells.

Specialized antigen-presenting cells (APC), known as dendritic cells (DC), play a pivotal role in initiating primary immune responses. Several vector systems, including adenoviral vectors, retroviral vectors, hemagglutinating virus of Japan-related vectors, and the electroporation, have been shown to transduce genes into mouse and human but not rat DC. However, there is no direct evidence to support the view that the currently used vector systems are able to transduce genes into mature DC. Inasmuch as most, if not all, gene transfer studies investigating DC or DC-related cell populations are performed employing heterogeneous-groups of cells, it is therefore important to determine the extent to which gene transduction occurs in bona fide DC. In this study, we provide evidence that none of these vector systems are able to transfer genes into mature rat DC, which are derived from bone marrow cells (BMC), driven by Flt3/Flk2 ligand and IL-6, and purified with CD161a. Nevertheless, the most efficient gene transduction was observed with developing DC progenitor cells during long-term culture of rat BMC. Successful gene transfer was achieved after 2-week culture with an HIV-based lentiviral vector system.

Animals↗
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Isolation of hepatocyte-like cells from mouse embryoid body cells.

We previously reported that embryoid body (EB) cells derived from embryonic stem (ES) cells are capable of differentiating into functional hepatocyte-like cells both in vitro and in vivo. Because transplantation of EB-derived cells into the liver via the spleen resulted in a low incidence of teratoma formation, purification of hepatocyte-like cells is required to prevent teratoma formation. The aim of this study was to purify hepatocyte-like cells from cultured EBs. For the isolation of hepatocyte-like cells, EBs cultured for 15 days were treated with trypsin-EDTA. The disaggregated cells were plated on a gelatin-coated dish as a monolayer. These cells were separated by Percoll gradient centrifugation, enriched by magnetic cell sorting, and purified by FACS. The purified hepatocyte-like cells in monolayer cultures were positive for immunostaining for albumin and expressed albumin mRNA, but not Oct3/4 mRNA. Transplantation of the purified hepatocyte-like cells derived from mouse ES cells might be an effective treatment for liver failure.

Animals↗
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Phenotype and functional identity of GM-CSF-independent dendritic cells generated by long-term propagation of DC progenitor cells in bone marrow cells and skin Langerhans cells.

Evidence is provided that dendritic cells (DC) generated by either long-term bone marrow cell (BMC) culture with Flt3L and interleukin-6 (IL-6), or after short-term BMC culture with granulocyte macrophage-colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4), contain heterogeneous cell populations of admixed DC and Mphi, regardless of the cytokine source. By employing GM-CSF-independent culture systems with the aid of Flt3/Flk-2 ligand and IL-6 and phenotypic characterization of BMC-derived DC and skin Langerhans cells (LC), revealed similar phenotypes. Furthermore, CD103 (OX62), which is widely used for rat DC separation, was found to be insufficient to enrich DC, due to downregulation of the marker. In this regard, the most efficient selection of rat DC, was obtained by CD161a (NKR-P1A), a member of the C-type lectin family. Despite the phenotypic similarity with BMC-derived DC, the nucleus of LC showed a distinct morphology. A large population of DC generated by Flt3L/IL-6 from GM-CSF receptor-deficient mice by do not express NK1.1 (NKR-P1B and NKR-P1C). The profiles for BMC-derived DC were the same as for skin Langerhans cells.

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Results of pancreatectomy with radiation therapy for pancreatic cancer.

BACKGROUND/AIMS: Surgical resection provides the only chance for long-term survival for adenocarcinoma of the pancreas. However, a major problem of surgery appears to be post-resection recurrence. The purpose of the current study was to evaluate the efficacy of intraoperative radiotherapy (IORT) and/or external beam radiotherapy (EBRT) in combination with resective surgery. METHODOLOGY: 86 patients received radiotherapy combined with resection surgery and 64 patients received surgery alone. Of 86 patients, 37 received postoperative EBRT, 14 received IORT, and 31 received both. The primary outcome variable analyzed was survival. RESULTS: The survival curve in patients who received radiotherapy combined with resective surgery was significantly better than that in patients who only received surgery (MST: 12.8 vs. 7.9 months). The number of patients in both groups was equally populated on the basis of potentially prognostic factors such as gender and age of patients, type of resection, vascular resection, location of the tumor, and pTNM classification. Among the subgroups of the patients, adjuvant radiotherapy showed significant survival benefit in the patient group with pT3 tumor, pN positive and R0 surgery. CONCLUSIONS: Adjuvant radiotherapy including TORT with resection surgery for adenocarcinoma of the pancreas is accomplished with acceptable risk and provides significant survival benefit.

Adenocarcinoma↗