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S Mizuno

Publications and source records attributed to S Mizuno.

At least 289 records · Page 16Linked to original sources
PubMed1994

Interleukin-1 beta-modulated gene expression in immortalized human chondrocytes.

Immortalized human chondrocytes were established by transfection of primary cultures of juvenile costal chondrocytes with vectors encoding simian virus 40 large T antigen and selection in suspension culture over agarose. Stable cell lines were generated that exhibited chondrocyte morphology, continuous proliferative capacity (> 80 passages) in monolayer culture in serum-containing medium, and expression of mRNAs encoding chondrocyte-specific collagens II, IX, and XI and proteoglycans in an insulin-containing serum substitute. They did not express type X collagen or versican mRNA. These cells synthesized and secreted extracellular matrix molecules that were reactive with monoclonal antibodies against type II collagen, large proteoglycan (PG-H, aggrecan), and chondroitin-4- and chondroitin-6-sulfate. Interleukin-1 beta (IL-1 beta) decreased the levels of type II collagen mRNA and increased the levels of mRNAs for collagenase, stromelysin, and immediate early genes (egr-1, c-fos, c-jun, and jun-B). These cell lines also expressed reporter gene constructs containing regulatory sequences (-577/+3,428 bp) of the type II collagen gene (COL2A1) in transient transfection experiments, and IL-1 beta suppressed this expression by 50-80%. These results show that immortalized human chondrocytes displaying cartilage-specific modulation by IL-1 beta can be used as a model for studying normal and pathological repair mechanisms.

Antigens, Viral, Tumor↗
PubMed1994

Use of transcriptional-enhancer elements responsive to ras, protein kinase A and protein kinase C to evaluate inhibitors of specific signal transduction pathways.

To evaluate ras-mediated signal transduction, we constructed a transient transfection assay system that measures chloramphenicol acetyl transferase activity expressed under the transcriptional-enhancer elements responsive to ras, protein kinase C, and protein kinase A in NIH3T3 cells. Characterization of the assay system with several known activators and inhibitors of signal transduction pathways proved that our system could reliably evaluate agents that affect individual pathways. Pirarubicin ((2"R)-4'-tetrahydropyranyladriamycin, THP), which has recently been found able to reverse ras-transformed cells, appeared to selectively inhibit the ras signal transduction pathway.

3T3 Cells↗
PubMed1994

Evaluation of cancer prevention strategies by computerized simulation model: methodological issues.

A computerized simulation model developed to evaluate the potential impact of primary and secondary prevention is discussed from methodologic perspectives. In the simulation model, named CANSAVE (Cancer Strategy Analysis and Validation of Effect), the natural history of cancer was modeled as a Markovian stochastic process from cancer-free state to death. The lung cancer death rate among Japanese males was projected for 50 years to the year 2041. The simulation showed that the age-adjusted death rate would increase and reach a peak of 166 per 100,000 in 1989 and then decrease to 148 in 2003. It then shows a tendency to increase again, up to 255 in 2028. This change may be attributed to a lower smoking initiation rate among those born in the 1930s. Promotion of mass screening programs exhibits a more prompt effect than antismoking efforts, but the reduction in annual deaths is expected to be only 11%, even if a 100% participation is realized by the year 2000. The reduction in smoking initiation rate, on the other hand, begins to show a visible effect very slowly. It was predicted that a 1% annual reduction in smoking initiation rate would result in a 20% decrease in the number of deaths in 2041. The smoking cessation program is in the middle with regard to promptness. The predicted reductions in lung cancer deaths in 2041 were 13, 47, and 66%, respectively, when the annual smoking cessation rate was increased from 0.46% (present status) to 1, 3, and 5%. The combined application of all three preventive measures seems essential to realize the most effective reduction in lung cancer deaths.

Adult↗
PubMed1994

Role of lymphocytes in spontaneous regression of experimentally transplanted canine transmissible venereal sarcoma.

Sensitized peripheral blood lymphocytes (PBL) obtained from canine transmissible venereal sarcoma (CTVS)-regressed dogs were more cytotoxic against CTVS cells than non-sensitized PBL from untreated dogs. Cytotoxicity shown by sensitized PBL was inhibited significantly by the addition of anti-major histocompatibility complex (MHC) class II mouse monoclonal antibody as well as that of anti-dog thymocyte rabbit serum. The degree of cytotoxic activity shown by lymphokine activated killer (LAK) cells induced from non-sensitized or sensitized PBL was similar to that of the activity shown by sensitized PBL. These LAK activities were also prohibited by the addition of anti-dog thymocyte rabbit serum. Immunohistochemical examination demonstrated that MHC class II antigens were expressed on the surface membrane of CTVS cells and thymocyte antigens were detected on the surface of the tumor infiltrating lymphocytes. From the results mentioned above, lymphocytes which play a central role in tumor regression are considered to be T cells. These cells might recognize MHC class II antigens on the surface membrane of CTVS cells in tumor regression.

Animals↗
PubMed1994

[Pathogenesis of spontaneous nephrosis in mice--urinary protein in nephrotic mice].

There is a paucity of model animals for naturally occurring nephrosis. The nephrotic mouse strain (ICGN) found from ICR mouse colony at National Institute of Health could be one of the most suitable model for nephrosis. We maintained the strain of mice which was originated from the hybrid between the nephrotic ICGN mice and ICR mice. Nephrosis is diagnosed with the presence of albumin band on SDS-PAGE of the urine. The detection of urinary albumin using SDS-PAGE could be valuable for early diagnosis of nephrosis in the mice. The total urinary protein concentration was determined on the course of nephrosis. The nephrotic mice showed slightly higher protein concentration between 2 and 6 days old as compared to control mice. Until 16 day old, it was maintained relatively low level. Thereafter, the total urinary protein increased gradually. However the diagnosis of nephrosis with total urinary protein alone may be limited due to the major urinary protein which can be detected even in normal rodents.

Albuminuria↗
PubMed1994

An analysis on the effect of blood transfusion on recurrence and survival in patients undergoing extended lymphadenectomy for colorectal cancer.

In a retrospective study data were collected from 644 patients with cancer of the colon or rectum undergoing curative surgery with extended lymphadenectomy to evaluate a possible effect of blood transfusion, given perioperatively, on tumor recurrence and patient survival. Univariate analysis showed depth of bowel wall invasion, number and level of lymph node metastases to be of highly significant prognostic factors. After 5 years the overall recurrence rate was 16.6% for the non-transfused (n = 223) and 26.1% for the transfused (n = 421; p < .01) patients, and survival rates showed borderline significance favoring the non-transfused patients (90.5% vs. 80.0% after 5 years; p < 0.05). However, after stratification for the prognostically important factors, in a multivariate analysis a possible detrimental effect of perioperative blood transfusions could not be demonstrated.

Adenocarcinoma↗
PubMed1994

Balloon electric shock ablation. A surgical technique for treatment of ventricular tachycardia: influence of endocardial scar on depth of ablation achieved.

Balloon electric shock ablation is a surgical technique that has been used for treatment of ventricular tachycardia. However, little is known about the energy requirements and precise electrode array best suited to achieve effective ablation of the target area while limiting injury to the surrounding myocardium. This study was designed to determine the effects of endocardial scar (often present at the "site of origin" of clinical ventricular tachycardia) on depth of ablation resulting from balloon electric shock ablation. A chronic canine model of endocardial scar (3.9 +/- 0.6 mm thick) was developed with the use of balloon electric shock ablation techniques. We compared depth of ablation achieved with balloon electric shock ablation with low-energy shocks (22 J per bead) in normal dogs versus those with chronic endocardial scar. No difference was found in depth of ablation in normal dogs and in the scar model (7.2 +/- 1.2 mm versus 6.2 +/- 1.0 mm). Depth of injury expressed as a percentage of wall thickness was not different in the two groups (61% +/- 11% versus 57% +/- 3%). We conclude that the presence of endocardial scar does not influence depth of injury resulting from balloon electric shock ablation. This data provides guidance for clinical application of the technique as a "closed heart" surgical approach for control of ventricular tachycardia. The data are also discussed in relation to energy levels currently used for direct current catheter ablation in patients with ventricular tachycardia.

Animals↗
PubMed1994

Perioperative blood transfusion promotes recurrence of hepatocellular carcinoma after hepatectomy.

BACKGROUND: Recent advances in liver surgery have reduced operative blood loss drastically, and in more than one half of the patients in our hospital, the liver resection can be accomplished without blood transfusion. METHODS: Two hundred fifty-two patients who underwent complete resection for hepatocellular carcinoma (HCC) were evaluated to assess the effect of perioperative blood transfusion on the recurrence of carcinoma. RESULTS: Carcinoma recurred in 55 (74.3%) of the 74 patients who received a transfusion, but in only 89 (50%) of the 178 patients who did not receive a transfusion (p = 0.0001). This effect was significant even when only a small amount of blood was transfused (p = 0.0001). Based on multivariate analysis, perioperative blood transfusion was a significant predictor for accelerated recurrence (p = 0.003), as were tumor invasiveness (vascular invasion or intrahepatic metastasis) (p = 0.0008) and background liver cirrhosis (p = 0.04). The recurrence-promoting effect of blood transfusion was markedly significant when the patient had either noninvasive HCC (p = 0.0005) or a cirrhotic liver (p < 0.0001). CONCLUSIONS: These results strongly suggest that perioperative blood transfusion substantially promotes the recurrence of HCC after hepatectomy. This effect must be considered and added to the risks of perioperative blood transfusion when formulating a surgical strategy for HCC.

Adult↗
PubMed1994

[A case underwent separate operation for AAE, AR and TAA using elephant trunk method].

A 20-year-old man with Marfan syndrome was recommended emergency operation for impending rupture of TAA. Because he was in the state of acute heart failure due to coexisting AAE and AR, so the simultaneous operations for AAE, AR and TAA were needed. He underwent Bentall, arch replacement and elephant trunk operation utilizing separate extracorporeal circulation and circulatory arrest. Chest CT, taken after 5 months postoperatively, revealed only a small amount of thrombus in TAA. Anticoagulation therapy stood in the way of aneurysmal thrombo-exclusion. The second operation, grafting of descending thoracic aorta, was performed 6 months later and elephant trunk made the second operation easier. Now 12 months passed after the second operation, he is in good health.

Adult↗
PubMed1993

Cloning of a canine gene homologous to the human interleukin-8-encoding gene.

We cloned a 2.3-kb sequence homologous to the gene (hIL8) encoding human interleukin-8 (hIL-8) from the canine genome. The sequence may encode an 11.3-kDa protein consisting of 101 amino acids, sharing 75, 80 or 85% identity with the human, rabbit or porcine IL-8 proteins, respectively. Southern and Northern blot analyses indicated that the cloned sequence appeared to exist as a single copy in the canine genome, and that its expression was inducible with lipopolysaccharide in canine mononuclear cells, respectively. Thus, it seems very likely that the cloned gene is a canine homologue of hIL8.

Amino Acid Sequence↗
PubMed1993

Different behavior of chromatin domains encompassing fibroin heavy-chain gene in active, temporarily inactive, and permanently inactive transcriptional states in silk gland nuclei.

Chromatin structures of an approximately 46-kilobase pair region encompassing fibroin heavy chain gene of the silkworm, Bombyx mori, were compared in active (in the posterior silk gland nuclei of the fifth instar larvae), temporarily inactive (in the posterior silk gland nuclei of the fourth molting stage larvae), and permanently inactive (in the middle silk gland nuclei of the fifth instar larvae) transcriptional states. Chromatin structure of the second exon, the major body of the protein-encoding region, was highly sensitive to both DNase I and methidiumpropyl EDTA-Fe(II) in the active state but highly resistant to those agents in both temporarily and permanently inactive states, except that the fibroin "amorphous" region-encoding subregions remained relatively sensitive to DNase I. Distributions of DNase I hypersensitive sites in the 5' upstream region were generally similar between active and temporarily inactive states, but those of the permanently inactive state were markedly different. In the promoter-enhancer region, phosphodiester bonds between nucleotide positions -41 and -42 and also -42 and -43 were remarkably hypersensitive to DNase I in the active chromatin, but the same positions in the other two states were not.

Animals↗
PubMed1993

Characterization of a 64-kd protein phosphorylated during chemotactic activation with IL-8 and fMLP of human polymorphonuclear leukocytes. I. Phosphorylation of a 64-kd protein and other proteins.

Interleukin-8 (IL-8) such as LUCT (lung giant cell carcinoma-derived chemotactic protein), NAP (neutrophil activating protein) and MDNCF (monocyte-derived neutrophil chemotactic factor), and formylmethionyl-leucyl-phenylalanine (fMLP) are well-known chemoattractants for human polymorphonuclear leukocytes (PMNs) and are able to stimulate phosphorylation of 64-kd protein (p64) in these leukocytes. To elucidate the molecular mechanism of PMN activation with chemoattractants, we investigated the phosphorylation process of p64 in an intact cell. 32P-Labeled PMNs were stimulated with LUCT/IL-8, fMLP, leukotriene B4, or C5a, and phosphorylated proteins were analyzed by two-dimensional electrophoresis and autoradiography. A marked phosphorylation of p64 was observed after stimulation. A new spot of phosphorylated p64 (pp64) could be detected on the gel stained with Coomassie Brilliant Blue, indicating that the isoelectric point (pI) of p64 shifted from 5.3 to a more acidic pI by the phosphorylation forming pp64. The spot of pp64 was shown to be dephosphorylated to p64 by treatment with calf intestine alkaline phosphatase. Other proteins having molecular masses 82, 66, 58, 55 and 50 kd were also phosphorylated. The fMLP-stimulated phosphorylation was time-dependent and saturated within 5 min. Maximum stimulation was achieved with 10 nM fMLP. Phosphoamino acid analysis revealed phosphorylation of serine residues in pp64. Staurosporine (100 nM) and W-7 (100 microM) significantly inhibited the phosphorylation of p64, but H-7 slightly inhibited it. H-8 and herbimycin A did not effect phosphorylation. Phorbol myristate acetate was found to stimulate significantly. Protein kinase C did not stimulate the phosphorylation. These data suggest that protein kinase C and calmodulin-like protein are indirectly involved in the phosphorylation of p64 during chemoattractant-activation of PMN.

Alkaline Phosphatase↗