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T Fujimura

Publications and source records attributed to T Fujimura.

At least 19 recordsLinked to original sources
PubMed1992

Pol of gag-pol fusion protein required for encapsidation of viral RNA of yeast L-A virus.

Double-stranded RNA viruses have an RNA-dependent RNA polymerase activity associated with the viral particles which is indispensable for their replication cycle. Using the yeast L-A double-stranded RNA virus we have investigated the mechanism by which the virus encapsidates its genomic RNA and RNA polymerase. The L-A gag gene encodes the principal viral coat protein and the overlapping pol gene is expressed as a gag-pol fusion protein which is formed by a -1 ribosomal frameshift. Here we show that Gag alone is sufficient for virus particle formation, but that it fails to package the viral single-stranded RNA genome. Encapsidation of the viral RNA requires only a part of the Pol region (the N-terminal quarter), which is presumably distinct from the RNA polymerase domain. Given that the Pol region has single-stranded RNA-binding activity, these results are consistent with our L-A virus encapsidation model: the Pol region of the fusion protein binds specifically to the viral genome (+) strand, and the N-terminal gag-encoded region primes polymerization of Gag to form the capsid, thus ensuring the packaging of both the viral genome and the RNA polymerase.

Amino Acid Sequence↗
PubMed1992

Interaction of two cis sites with the RNA replicase of the yeast L-A virus.

L-A is a 4.6-kilobase double-stranded RNA virus of Saccharomyces cerevisiae. The in vitro L-A replication reaction ((-)-strand synthesis) requires an internal site 400 bases from the 3' end in addition to the 3'-terminal 30 nucleotides of the L-A (+)-single-stranded RNA. Elimination of the internal site reduces the template activity 5-10-fold. Here we investigate how the internal site can stimulate the replication reaction which starts at the 3' end of the template. When these two sites are split into two distinct RNA molecules, the internal site can no longer stimulate replication (no trans-activation). However, establishment of an intermolecular hydrogen bonding between these RNAs restored the replication-enhancing activity of the internal site. This result is consistent with a model wherein L-A's RNA polymerase interacts first with the internal site and then with the 3' end site by either looping or by a local dissociation-reassociation mechanism. These results, however, clearly eliminate anchored tracking and sliding models which require continuity of the RNA molecule between these two cis sites.

Autoradiography↗
PubMed1992

Effect of intra-hepatoarterial infusion of MMC and CDDP for gastric cancer patients with liver metastases.

The influence of operative treatment and chemotherapy on the prognosis in 93 gastric cancer patients with liver metastasis was studied. Chemotherapy included the systemic administration of mitomycin C (MMC) (39 patients), an intra-hepatoarterial infusion of MMC (MMC IAC group) (19 patients) and an intra-hepatoarterial infusion of MMC and cisplatin (CDDP) (MMC + CDDP IAC group) (24 patients). Either MMC or MMC and CDDP were given in 1-4 courses every 3-4 weeks from the first one to two post operative weeks. The response rate was 4 per cent (1/23), 29 per cent (5/17) and 73 per cent (17/23) for MMC systemic administration, MMC IAC and MMC + CDDP IAC, respectively, with a significantly high rate of effectiveness for the MMC + CDDP IAC. In addition, regarding the median survival period, the MMC + CDDP IAC group showed 11.8 months, as compared with 2.9 months for other chemotherapeutic treatments, indicating a good prognosis regardless of any possible resection of the primary lesion. A Cox proportional hazard model revealed the treatment by MMC + CDDP IAC alone to be a significant independent factor. These results indicated that MMC + CDDP intra-arterial chemotherapy is an effective approach to gastric cancer with liver metastasis.

Adult↗
PubMed1992

Is bile or are pancreaticoduodenal secretions related to gastric carcinogenesis in rats with reflux through the pylorus?

Male Wistar rats were subjected to one of three types of operative reflux procedure that allowed part or all of the duodenal contents to flow back into the stomach through the pylorus, thus producing models of bile reflux alone, pancreaticoduodenal reflux alone, and combined reflux. All surviving animals were killed 50 weeks after surgery and the development of gastric cancer was assessed. No cancer was seen in 16 animals with pancreaticoduodenal reflux or in 32 control animals with gastrotomy, whereas 2/8 animals with bile reflux and 11/29 animals with combined reflux had gastric carcinoma. Compared with the control group, the incidence of carcinoma in animals with bile or combined reflux was significantly higher (P less than 0.05 and P less than 0.01 respectively). All carcinomas developed in the antral area near the pylorus. Adenomas were observed only in the groups of animals developing carcinoma and occurred in the same region of the stomach. These results suggest that bile, and not pancreaticoduodenal secretions, is the component of the duodenal contents responsible for the development of gastric carcinoma.

Adenocarcinoma↗
PubMed1992

Induction of macrophage interleukin-1 production by Listeria monocytogenes hemolysin.

Listeriolysin O produced by a hemolytic strain of Listeria monocytogenes was purified from the ammonium sulfate precipitate of a culture supernatant through the steps of ion-exchange chromatography and gel filtration. The purified hemolysin finally gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with a molecular weight of 58,000. When peritoneal exudate macrophages were stimulated with purified hemolysin, we found a high level of IL-1 activity as determined by thymocyte costimulator assay in the culture supernatant. Cell-associated and intracellular IL-1 activity was also detected. The activity in the supernatant or membrane was blocked by polyclonal antibody to murine IL-1 alpha. Moreover, IL-1-specific mRNA expression could be detected in the macrophages stimulated with listeriolysin O by Northern blot analysis. Possible contamination by LPS of the listeriolysin O preparation did not seem to contribute to the induction of macrophage IL-1 production.

Animals↗
PubMed1992

Duodenal reflux through the pylorus induces gastric adenocarcinoma in the rat.

We investigated whether duodenal reflux through the pylorus is involved in the development of gastric cancer. Male Wistar rats weighing 230-250 g were subjected to three types of operative procedures: (i) allowing reflux through the pylorus; (ii) allowing reflux through a gastrojejunal stoma; and (iii) gastrotomy. No carcinogens were given, and the animals were killed 50 weeks after surgery. No cancers were detected in any of the 18 animals with gastrotomy. In contrast, seven (41%) of 17 animals with reflux through the pylorus and four (31%) of 13 animals with reflux through the stoma had adenocarcinoma. Differences in the incidence between both reflux groups and the gastrotomy group were significant (P < 0.01 and P < 0.05 respectively). All of the adenocarcinomas developed in the pyloric mucosa near the pylorus in the animals with reflux through the pylorus, and in the oxyntic mucosa near the stoma in those with reflux through the stoma. Adenocarcinomas appeared as a polyploid mass with or without slight central erosion. Most of the adenocarcinomas were of the well-differentiated tubular type, and the others were of the mucinous type. No differences in either the histologic type or depth of invasion of the adenocarcinoma were recognized between the two duodenogastric reflux groups. Precancerous or paracancerous lesions, such as adenoma, adenocystic proliferation, and stomal pseudopyloric metaplasia, were more frequently found in the same region as the adenocarcinomas. These findings suggest that duodenogastric reflux in the rat has potent carcinogenic activities not only in the oxyntic mucosa through the stoma, but also in the pyloric mucosa through the pylorus.

Adenocarcinoma↗
PubMed1992

[Combined medical and surgical treatment of 74 cases of acute type III aortic dissection].

In the early period up to 1986, our treatment of acute type III dissection was anti-hypertension drug therapy as a rule, and Collins operations were performed in two cases of progressive hemothorax. Among 21 patients receiving medical therapy, five died of rupture, and three operated cases died of multiple organ ischemia, and then the hospital mortality was 40%. Since 1987, we have selected hypotensive treatment of strictly maintaining blood pressure less than 120mmHg for the completely thrombosed type of the dissected lumen, and the emergency operation of ringed intraluminal graft insertion (RIG operation) for the blood-flow type and aneurysm formation type of the dissected lumen, diagnosed by the emergency cine-angiography. As the result, among 51 cases having hypotensive therapy, one died of respiratory failure. In the 23 operated cases, in which RIG operation and/or arterial reconstruction was performed, four died of multiple organ ischemia. The hospital mortality was 8%, which was significantly improved compared with that of the early period.

Acute Disease↗
PubMed1992

[Practical use of mortality statistics and mass examination results by health workers in the local authority of the community].

In Kochi prefecture, the prefectural health service bureau tabulates both mortality statistics and mass examination results for each community and the tabulated report is sent annually to public health services staff in each local authority. While recognizing its limitations, methods of how to use the annual report are demonstrated. For example comparison of the mortality statistics and the mass examination results of the male population of A town, which is administered by Susaki Health Center, to that of the combined male population of all the towns administered by the health center shows that although the mortality rate for cerebrovascular disease for the A town-male population had been much higher than that of the combined male population in the early 1980's, the difference disappeared in the late 1980's. On the other hand, prevalence of systolic hypertension in the A town-male population continued to be higher than that for the combined male population in the late 1980's. Therefore hypertension prevention programs appears to still have significance in the A town-male population. Certain weaknesses exist in this annual report. In the comparison of mass examination results among different populations, the presence of selection bias of those receiving examinations should be considered. Standardization of mass examination procedures and quality controls of the examinations should also be considered. To get health workers to utilize the annual report further, the reported items should be improved. Particularly useful would be tabulation by residential subdivision and occupation.

Community Health Services↗
PubMed1992

[Angiographic studies of atherosclerotic changes in coronary vein grafts after operation].

A total of 230 vein grafts were studied angiographically in 116 unselected survivors of 260 coronary bypass operations performed from May 1977 through October 1989 in order to investigate atherosclerotic changes in coronary vein grafts after operation. These patients were divided into three groups according to the interval from operation to angiography. In group A (30 patients) the interval was less than one year (mean interval 8.2 months), in group B (73 patients) from one to five years (mean interval 19.2 months) and in group C (13 patients) more than 5 years (mean interval 96.6 months). Fifty-five vein grafts were in group A, 153 vein grafts in group B and 22 vein grafts in group C. The graft patency rate of each group was 83.6%, 89.5% and 90.9% respectively (N.S.). To classify angiographic appearances we believe to be caused by atherosclerosis, we devised a grading system. Category I indicated that the graft outline was completely smooth without any irregularity; Category II indicated that less than 50% of the estimated surface area of the graft intima was irregular; Category III indicated that more than 50% of the intima was involved. Significant stenosis indicated narrowing reducing the lumen to less than 50% of the graft. Of the 203 patent grafts 181 grafts (89%) were in Category I, 22 grafts (11%) in Category II, but no graft in Category III. In group A of the 46 patent grafts 45 grafts (98%) were classified as Category I and 1 graft (2%) was classified as Category II.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Expression of a monocot LHCP promoter in transgenic rice.

The beta-glucuronidase (GUS) gene linked to the promoter of rice light harvesting chlorophyll a/b-binding protein of photosystem II (LHCPII) was introduced into rice by electroporation. Expression of the GUS gene with the LHCP promoter in transformed protoplasts and callus was much lower than with the cauliflower mosaic virus (CaMV) 35S promoter. In green organs, however, LHCP-GUS activity with the LHCP promoter was 10-fold higher than that with the CaMV 35S promoter. Expression of the LHCP-GUS gene was detected in leaves, stems and floral organs but not in roots. Histochemical analysis of leaves showed that the GUS gene was expressed specifically in green tissues. In selfed seeds of the transformants, GUS gene expression was detectable only in the germinated embryos after greening. Northern blot analysis revealed that transcription of the GUS gene with the LHCP promoter was not detectable in dark-grown seedlings of transformants but was induced by exposure to light. These results show that regulation of the introduced chimeric gene in transgenic plants was characteristic of the LHCP gene itself.

Blotting, Southern↗
PubMed1991

Expression of yeast L-A double-stranded RNA virus proteins produces derepressed replication: a ski- phenocopy.

The plus strand of the L-A double-stranded RNA virus of Saccharomyces cerevisiae has two large open reading frames, ORF1, which encodes the major coat protein, and ORF2, which encodes a single-stranded RNA-binding protein having a sequence diagnostic of viral RNA-dependent RNA polymerases. ORF2 is expressed only as a Gag-Pol-type fusion protein with ORF1. We have constructed a plasmid which expresses these proteins from the yeast PGK1 promoter. We show that this plasmid can support the replication of the killer toxin-encoding M1 satellite virus in the absence of an L-A double-stranded RNA helper virus itself. This requires ORF2 expression, providing a potential in vivo assay for the RNA polymerase and single-stranded RNA-binding activities of the fusion protein determined by ORF2. ORF1 expression, like a host ski- mutation, can suppress the usual requirement of M1 for the MAK11, MAK18, and MAK27 genes and allow a defective L-A (L-A-E) to support M1 replication. These results suggest that expression of ORF1 from the vector makes the cell a ski- phenocopy. Indeed, expression of ORF1 in a wild-type killer makes it a superkiller, suggesting that a target of the SKI antiviral system may be the major coat protein.

Capsid↗
PubMed1991

Effect of sodium chloride on pirarubicin induced cell killing in P388 mouse leukemia cells.

The effect of sodium chloride on the cytotoxicity of 4'-O-tetrahydropyranyldoxorubicin (pirarubicin), a novel anthracycline derivative, was investigated on P388 mouse leukemia cells in vitro. The modifications in efficiency of uptake and killing action of pirarubicin were found to be dependent on the ionic strength of the medium. The relationship between intracellular drug accumulation into cells and cell killing was pointed out.

Animals↗
PubMed1991

[Treatment of gastric cancer patients with peritoneal metastasis by continuous hyperthermic peritoneal infusion with mitomycin C and cisplatin].

Following the resection of its primary lesion, continuous hyperthermic peritoneal perfusion (CHPP) with anticancer drug (mitomycin C, cisplatin) containing warmed physiological saline was performed on gastric cancer having peritoneal dissemination, and the effect of CHPP was examined by second look operation (SLO). The subjects were 41 cases of gastric cancer with peritoneal dissemination but without hepatic metastasis, which we have experienced in the past 7 years. The prognosis of these CHPP-treated cases was such that 50% survival period, 3 year survival rate and 5 year survival rate were 398 days, 28.5 and 12%, respectively. Comparison of the effects of CHPP by SLO revealed remarkable diminution of the peritoneal dissemination in 7 (44%) of 16 cases and disappearance of the ascites with a single course of CHPP in 7 of ascitic cases. Long-term survival (greater than 3 years) was noted in 4 of the CHPP-treated cases. Side effects were renal insufficiency, leukopenia and small intestinal perforation in 2(5), 2(5) and 1 cases (2%), respectively. The above results suggested the effectiveness of CHPP for the treatment of gastric cancer having peritoneal dissemination.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

[Clinical experiences with hyperthermochemotherapy of hepatic metastasis from gastric cancer].

Thermochemotherapy was performed on gastric cancer cases of hepato-metastasis. The subjects were 12 gastric cancer cases having hepato-metastatic lesions (10 synchronous, 2 heterochronous). Using 8 or 13.58 MHz-dielectric heating apparatus, thermotherapy was carried out for 40-60 min (twice a week, 5-35 times, averaging 12.8 per case) at an intra-tumoral temperature greater than 42 degrees C. Chemotherapy consisted of hepato-arterial infusion of MMC 10 mg/BW, CDDP 75 mg/m2 once per 3-4 weeks and consecutive daily administration p.o. of UFT 800 mg/BW. Effect greater than PR was noted in 75% (9/12) on the whole and in 100% (5/5) and 57% (4/7) for H1-2 and H3, respectively. Mean and 50% survival periods were 9.3 and 7.2 months, respectively, with a one-year survival rate of 38%. Chemotherapy-induced side effects were nausea and vomiting in 83% and leukopenia and thrombopenia in 67%, while the only thermotherapy-induced side effect was subcutaneous fatty tissue necrosis in 3 cases. The above results suggested the effectiveness of the present thermochemotherapy in the treatment of hepato-metastasis of gastric cancer.

Administration, Oral↗
PubMed1991

[Effects of reflux of bile and/or pancreaticoduodenal juice on gastric carcinogenesis in rats].

The present study was designed to investigate which fraction of duodenal contents was responsible for gastric carcinogenesis, bile or pancreaticoduodenal juice. A series of 61 male Wistar rats were subjected to one of following four operative procedures: total reflux (TR, n = 17), bile reflux (BR, n = 8), or pancreaticoduodenal reflux (PDR, n = 16), and simple laparotomy (control, n = 20). Fifty weeks after operations the animals were sacrificed. The incidence of gastric adenocarcinoma was 7/17 (41%) in TR group, 2/8 (25%) in BR group, 0/16 (0%) in PDR group, and 0/20 (0%) in control group. The incidence of cancer in the both TR and BR groups were significantly higher than PDR and control groups, respectively. Histologically, lesions of gastric cancers showed tubular adenocarcinoma or mucinous adenocarcinoma. There was a significant difference in the intragastric pH between the first three reflux groups and control group. The concentrations of the total bile acids of the both TR and BR groups were significantly higher than PDR and control groups, respectively. These results suggested that duodenogastric reflux induces adenocarcinoma in the rat gastric mucosa and bile rather than pancreatico-duodenal juice is related to increased risk for gastric cancer.

Animals↗
PubMed1991

[Prophylactic effect of allopurinol mouthwash against stomatitis induced by the chemotherapy (PMUE regimen) for gastrointestinal malignancies].

For prevention of the chemotherapy-induced stomatitis we administered allopurinol mouthwash to 15 out of 38 patients who underwent PMUE regimen. The severity of stomatitis was graded on five scales according to the criteria of Japan Society For Cancer Therapy. The incidence of stomatitis was defined as patients number with stomatitis above Grade 2/all patients number. Six of 23 patients which were not given allopurinol mouthwash (control group) developed stomatitis of Grade 1 (three patients), Grade 3 (two), or Grade 4 (one). Only one patient given allopurinol mouthwash (AMW group), however, suffered from Grade 1 stomatitis. The incidence of stomatitis was 13.0% for a control group and 0% for an AMW group. The average graded toxicity was 0.07 for the AMW group significantly lower than 0.57 for the control group. There was no significant difference between the two groups in other clinical adverse effects or abnormal laboratory data. These results suggested that allopurinol mouthwash regimen was well tolerated and effective for prevention of the chemotherapy induced stomatitis.

Allopurinol↗