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Biomedical subjects

S Satoh

Publications and source records attributed to S Satoh.

At least 109 records · Page 6Linked to original sources

Cloning of a cDNA encoding EIN3-like protein (DC-EIL1) and decrease in its mRNA level during senescence in carnation flower tissues.

A cDNA clone encoding a putative EIN3-like protein (DC-EIL1) was obtained from total RNA isolated from senescing carnation (Dianthus caryophyllus L.) petals using RT-PCR and RACE techniques. The cDNA (2382 bp) contained an open reading frame of 1986 bp corresponding to 662 amino acids. The amino acid sequence of the N-terminal half of the protein, ranging from 80-300 amino acid residues, had 84% identity with that of the corresponding regions of Arabidopsis EIN3 and tobacco TEIL, although the overall identity was 49% and 52%, respectively. Northern blot analysis revealed that the amount of mRNA corresponding to DC-EIL1 decreased in flower tissues, especially in petals, during natural senescence and senescence induced by exogenously applied ethylene or ABA.

Amino Acid Sequence↗

[Blood concentrations and side effects of tacrolimus in a living renal transplantation].

In a living renal transplantation, the recipients are administered an immunosuppressive agent preoperatively. The drug exhibits a high incidence of side effects of special note. We examined the side effects of tacrolimus to evaluate the postoperative management of living renal transplantation. Hypertension, hyperglycemia, tachycardia and chest pain were found as the side effects. The blood concentration should be measured frequently to maintain the effective blood concentration and to prevent the side effect.

Adult↗

[A case of retroperitoneal fibrosis responding to steroid therapy].

A 73-year-old man presented with acute renal failure due to bilateral hydronephroses. Urography and CT scan revealed stenosis and medial deviation of the bilateral ureters surrounded by a soft tissue mass at the level of the 4-5th lumber vertebrae. Under a diagnosis of retroperitoneal fibrosis, bilateral nephrostomies were temporarily placed and prednisolone administration was initiated at a dose of 20 mg/day. Ureteral passage markedly improved within 2 weeks in association with a decrease in size of the retroperitoneal soft tissue mass. The steroid therapy was continued for 4 months with decreasing dosing schedule. The patient has been doing well without any signs of recurrence for 3 months after the cessation of the steroid therapy.

Aged↗

[Effects of cernitin pollen-extract (Cernilton) on inflammatory cytokines in sex-hormone-induced nonbacterial prostatitis rats].

Cernitin pollen-extract (Cernilton, CN) is a preparation made from eight kinds of pollen and has been used for various prostatic diseases in Japan and Europe. We reported previously that CN possessed a recovery action on the sex-hormone-induced nonbacterial prostatitis in rats. To clarify the possible mechanism of action of CN, we investigated the effects of CN on inflammatory cytokines (IL-1 beta, IL-6 and TNF-alpha) in the same model. Aged Wistar rats were castrated and injected 17 beta-estradiol (0.25 mg/kg/day, s.c.) for 30 days. CN (630 and 1,260 mg/kg, p.o.) or testosterone (2.5 mg/kg, s.c.) was administered for the last 14 days of the treatment of 17 beta-estradiol. In control rats, prostatic IL-6 and TNF-alpha contents were increased approximately 2-3 fold, and acinar glandular inflammation and stromal proliferation were found histopathologically, as compared with those of intact rats. On the other hand, CN decreased the increased contents of cytokines in a dose-dependent manner. The histopathological changes mentioned above were restored in rats treated with 1,260 mg/kg. Testosterone also ameliorated them significantly. These results indicate that CN has an anti-inflammatory action, and that the inhibitory effect of CN on the prostatic inflammatory cytokine is an important factor in its action.

Animals↗

Comprehensive allelotyping of human intrahepatic cholangiocarcinoma.

We performed a genome-wide scan for loss of heterozygosity (LOH) in 22 intrahepatic cholangiocarcinoma (ICC) cases using 168 polymorphic microsatellite markers throughout all of the human chromosomes and 48 markers of which LOH is reportedly characteristic of hepatocellular carcinoma (HCC). Markers with LOH in more than 30% of informative cases were observed at 21 loci. Among these, eight markers on 6q (three loci), 4q (two loci), 9q, 16q, and 17p shared high frequencies of LOH with HCC in our previous study. As for gross appearance, mass-forming type tumors showed higher frequency of LOH (P < 0.001) compared with other types. Compared by tumor size (< or =5 cm versus >5 cm), number (multiple versus solitary), and the International Union Against Cancer TNM classification (stage IVB versus II-IVA), LOH was observed more frequently in advanced stages (P < 0.01, respectively). However, LOH frequency does not differ regardless of lymph node status (pN0 versus pN1). Frequent LOH on 1p36 including the p73 locus was noted in large tumors without lymph node metastasis. These suggest that ICC shares some common carcinogenic steps with HCC such as LOH of 4q and 6q and that inactivation of tumor suppressor genes on chromosome 1p36 contributes to progression of ICC but not to metastatic traits.

Adult↗

Arch-first reconstruction via median sternotomy. Short retrograde cerebral perfusion.

In December 1998, we introduced arch-first reconstruction for total aortic arch replacement via conventional median sternotomy in order to shorten the duration of retrograde cerebral perfusion (RCP). We used a separate straight graft for an elephant trunk, which allowed an easy subsequent distal anastomosis. The average RCP duration in this series was 32.1+/-5.8 min (mean+/-SD, range, 24-40 min, n=12), which was significantly shorter (p<0.05) than that of the conventional procedure (45.6+/-12.4 min, range, 34-65 min, n=8), in which we first perform a distal anastomosis. No significant differences in cardiopulmonary bypass time (268+/-81 min vs 258+/-42 min) nor operation time (518+/-213 min vs 517+/-82 min) between the two groups were observed. There was no hospital death in either group. One patient in the second series (conventional method) suffered temporary neurological disturbance. For acceptable RCP duration, total aortic arch replacement is currently the standard procedure in our institution for Stanford A type aortic dissection.

Anastomosis, Surgical↗

Mutational analysis of BRCA1 and BRCA2 and clinicopathologic analysis of ovarian cancer in 82 ovarian cancer families: two common founder mutations of BRCA1 in Japanese population.

We analyzed genetic alterations in BRCA1 and BRCA2 genes among 82 ovarian cancer families in Japan. The clinical characteristics of BRCA-associated ovarian cancer patients were compared with cases carrying no mutations as well as with population controls. Using a direct sequencing method, 45 of the 82 ovarian cancer families were found to carry BRCA1 or BRCA2 germ-line mutations (40 with BRCA1 and 5 with BRCA2). In 24 independent mutations of BRCA1, 5 recurrent mutations were found and 2 of them, the L63X and Q934X mutations, were detected in seven and eight independent families, respectively. In addition, 16 mutations of BRCA1 and 3 mutations of BRCA2 have never been described previously. In consideration of clinicopathological features, there was a significantly higher proportion of tumors with serous adenocarcinoma and of cases of advanced stages in the BRCA1 or BRCA2 cases than in those of the controls. On the other hand, there were no differences of mean age at diagnosis between patients with BRCA1 or BRCA2 mutation and those of the controls. Our results indicate that the features of BRCA-associated ovarian cancer in Japan appear to be similar to those in Western countries, and the L63X and Q934X mutations of BRCA1 appear to be common founder mutations unique to the Japanese population.

Adolescent↗

Enhancement of metastatic properties of pancreatic cancer cells by MUC1 gene encoding an anti-adhesion molecule.

MUC1 mucin expression has been shown to be associated clinicopathologically with metastasis and poor clinical outcome in a variety of tumors. To further investigate this finding experimentally, human pancreatic cancer S2-013 cells overexpressing MUC1 were used for spontaneous metastatic potential in nude mice. It was found that the number of lung metastases of MUC1 transfectants was significantly higher than that of control cells. To analyze the molecular mechanisms that underlie the increased metastatic activity, in vitro adhesion assays were performed. MUC1 mucin expression enhancedin vitro invasiveness and motility of S2-013 cells, and decreased the binding of S2-013 cells to type I collagen, Type IV collagen and laminin. Similar effects were not observed for cells expressing tandem repeat-deleted MUC1 cDNA. Adhesion properties were abolished by benzyl-alpha-GalNAc treatment, indicating that glycosylation of the extracellular domain of MUC1 was essential for these biological adhesive functions. Our data support the hypothesis that MUC1 expression contributes to the metastatic ability of pancreatic cancer cells.

Acetylgalactosamine↗

Chlorophyll b expressed in Cyanobacteria functions as a light-harvesting antenna in photosystem I through flexibility of the proteins.

Photosynthetic pigments bind to their specific proteins to form pigment-protein complexes. To investigate the pigment-binding activities of the proteins, chlorophyll b was for introduced the first time to a cyanobacterium that did not synthesize that pigment, and expression of its function in the native pigment-protein complex of cyanobacterium was confirmed by energy transfer. Arabidopsis CAO (chlorophyll a oxygenase) cDNA was introduced into the genome of Synechocystis sp. PCC6803. The transformant cells accumulated chlorophyll b, with the chlorophyll b content being in the range of 1.4 to 10.6% of the total chlorophyll depending on the growth phase. Polyacrylamide gel electrophoresis analysis of the chlorophyll-protein complexes of transformant cells showed that chlorophyll b was incorporated preferentially into the P700-chlorophyll a-protein complex (CP1). Furthermore, chlorophyll b in CP1 transferred light energy to chlorophyll a, indicating a functional transformation. We also found that CP1 of Chlamydomonas reinhardtii, believed to be a chlorophyll a protein, bound chlorophyll b with a chlorophyll b content of approximately 4.4%. On the basis of these results, the evolution of pigment systems in an early stage of cyanobacterial development is discussed in this paper.

Animals↗

Identification, characterization, and functional analysis of heart-specific myosin light chain phosphatase small subunit.

Myosin light chain phosphatase consists of three subunits, a 38-kDa catalytic subunit, a large 110-130-kDa myosin binding subunit, and a small subunit of 20-21 kDa. The catalytic subunit and the large subunit have been well characterized. The small subunit has been cloned and studied from smooth muscle, but little is known about its function and specificity in the other muscles such as cardiac muscle. In this study, cDNAs for heart-specific small subunit isoforms, hHS-M(21), were isolated and characterized. Evidence was obtained from an analysis of genome to suggest that the small subunit was the product of the same gene as the large subunit. Using permeabilized renal artery preparation and permeabilized cardiac myocytes, it was shown that the small subunit increased sensitivity to Ca(2+) in muscle contraction. It was also shown using an overlay assay that hHS-M(21) bound the large subunit. Mapping experiments demonstrated that the binding domain and the domain involved in the increasing Ca(2+) sensitivity mapped to the same N-terminal region of hHS-M(21). These observations suggest that the heart-specific small subunit hHS-M(21) plays a regulatory role in cardiac muscle contraction by its binding to the large subunit.

Amino Acid Sequence↗

Increased risk of prostate cancer and benign prostatic hyperplasia associated with a CYP17 gene polymorphism with a gene dosage effect.

The CYP17 gene (CYP17) codes for the cytochrome P450c17alpha enzyme, which mediates two key steps in the sex steroid synthesis. There is a polymorphism (a T-to-C substitution) in the 5'-untranslated region, which may influence the transcription level of CYP17 mRNA. There is a continuing controversy as to whether the variant allele is associated with a subset of breast cancer or polycystic ovary syndrome. In prostate cancer research, there are contradictory data concerning the CYP17 risk allele. We explored the association between CYP17 polymorphism and a risk of prostate cancer or benign prostatic hyperplasia (BPH) in a Japanese population. This study included 252 prostate cancer patients, 202 BPH patients, and 131 male controls. A 451-bp fragment encompassing the polymorphic site was amplified by PCR, treated with restriction enzyme MspA1, and electrophoresed on an agarose gel. The MspA1-undigested allele with the published sequence and the MspA1-digested variant allele were designated as A1 and A2, respectively. There was a significant difference (P < 0.05) in the genotypes between prostate cancer patients and male controls, and between BPH patients and male controls. Men with the A1/A1 CYP17 genotype had an increased risk of prostate cancer [odds ratio (OR), 2.57; 95% confidence interval (CI) = 1.39-4.78] and BPH (OR, 2.44; 95% CI = 1.26-4.72) compared with those with the A2/A2 genotype. Men with the A1/A2 genotype had an intermediate increased risk of prostate cancer (OR, 1.45; 95% CI = 0.84-2.54) and BPH (OR, 1.60; 95% CI = 0.89-2.87) compared with those with the A2/A2 genotype. The trend of an increasing risk of prostate cancer and BPH with an increasing number of the A1 allele was statistically significant (prostate cancer versus male control, P = 0.003; OR, 1.57; 95% CI = 1.16-2.12; BPH versus male control, P = 0.008; OR, 1.55; 95% CI = 1.12-2.13). There was no significant association between the CYP17 genotype and the tumor status (grade and stage) of prostate cancer. Our results suggest that the A1 allele of the CYP17 polymorphism is associated with an increased risk of prostate cancer and BPH, with a gene dosage effect. However, the CYP17 genotype does not seem to influence the disease status in prostate cancer.

Aged↗

Role of endogenous endothelins in catecholamine secretion in the rat adrenal gland.

We investigated the role of endogenous endothelins in catecholamine secretion in response to transmural electrical stimulation in the retrogradely perfused rat adrenal gland. (R)2-[(R)-2-[(S)-2-[[1-(hexahydro-1H-azepinyl)]carbonyl]amino-4-++ +methy l-pentanoyl]amino-3-[3-(1-methyl-1H-indoyl)]propionyl]amino-3-(2-+ ++pyridyl) propionic acid (FR139317; 0.03-3 microM), an endothelin ET(A) receptor antagonist, inhibited the electrical stimulation-induced epinephrine and norepinephrine output. Neither N-cis-2, 6-dimethylpiperidinocarbonyl-L-gamma-methylleucyl-D-1- methoxycarbonyl tryptophanyl-D-norleucine (BQ-788; 0.03-3 microM), an endothelin ET(B) receptor antagonist, nor phosphoramidon (1-100 mM), an endothelin-converting enzyme inhibitor, affected the catecholamine output responses. However, the inhibition by FR139317 of the catecholamine output responses was abolished by pretreatment with phosphoramidon (100 mM) or BQ-788 (3 microM). These results indicate that activation of endothelin ET(B) receptors by endogenous endothelins inhibits the catecholamine output responses under the condition in which endothelin ET(A) receptors are blocked. Exogenous endothelin-1 (1-100 nM) did not affect the catecholamine output responses, but it inhibited the responses under treatment with phosphoramidon and FR139317. Activation of endothelin ET(A) receptors may interfere with the endothelin ET(B) receptor-mediated inhibitory action on the neuronally evoked secretion of adrenal catecholamines.

Adrenal Glands↗

Cardioprotective effect of TY-12533, a novel Na(+)/H(+) exchange inhibitor, on ischemia/reperfusion injury.

The effects of 6,7,8, 9-tetrahydro-2-methyl-5H-cyclohepta[b]pyridine-3-carbonylguanidine maleate (TY-12533) on myocardial ischemia/reperfusion injury were evaluated in rats. Inhibitory effects of TY-12533, TY-50893 (the 9-chloro derivative of TY-12533) and cariporide on the platelet Na(+)/H(+) exchanger in vitro were almost equal at pH 6.2 and decreased at pH 6.7; but TY-12533 was four times more potent than TY-50893 and cariporide at pH 6.7. TY-12533, TY-50893 and cariporide administered before ischemia (0.01-1 mg/kg, i.v.) suppressed the ischemia/reperfusion-induced arrhythmias to the same extent in vivo; but TY-12533 was more effective than cariporide and TY-50893 when they were administered during ischemia (0.1-1 mg/kg). Similar results were obtained for the inhibitory effects of these drugs administered before ischemia (0.03-0.1 mg/kg, i.v.) and during ischemia (0.1-1 mg/kg) on the ischemia/reperfusion-induced myocardial infarction. These differences between TY-12533 and the other drugs in vitro and in vivo may be ascribed to the pK(a) values of the guanidinium moiety of TY-12533 (6.93), TY-50893 (6.35) and cariporide (6.28).

Aconitine↗

Hemorheological abnormalities in experimental cerebral ischemia and effects of protein kinase inhibitor on blood fluidity.

The aim of this study was to investigate the mechanisms of the pathogenesis of hyperviscosity following cerebral ischemia. Focal ischemia was produced by embolic occlusion of the right middle cerebral artery (MCA) in rats for 1 hour, followed by recirculation. Twenty-four hours after MCA occlusion, fasudil, a protein kinase inhibitor, was administered intraperitoneally. Blood samples were taken from the abdominal aorta, and viscosity was measured using a cone-plate viscometer. The viscosity of whole blood in the ischemic attack group was significantly increased compared with the sham operated group 24 hours after MCA occlusion. Fasudil dose-dependently and significantly decreased the blood viscosity, and reduced to the normal range after administration of 10 mg/kg of fasudil (sham-operated rats, 5.17+/-0.05 cP; pre dose/ischemic rats, 6.05+/-0.08 cP; post dose/ischemic rats, 5.23+/-0.14 cP; 37.5 sec(-1)). Our findings suggest that cerebral ischemia induces a potent, systemic and long-lasting hyperviscosity, and that the inhibition of protein kinases, especially rho kinase, is efficacious in preventing this hyperviscosity.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

Expression of genes responsible for ethylene production and wilting are differently regulated in carnation (Dianthus caryophyllus L.) petals.

Carnation petals exhibit autocatalytic ethylene production and wilting during senescence. The autocatalytic ethylene production is caused by the expression of 1-aminocyclopropane-1-carboxylate (ACC) synthase and ACC oxidase genes, whereas the wilting of petals is related to the expression of the cysteine proteinase (CPase) gene. So far, it has been believed that the ethylene production and wilting are regulated in concert in senescing carnation petals, since the two events occurred closely in parallel with time. In the present study, we investigated the expression of these genes in petals of a transgenic carnation harboring a sense ACC oxidase transgene and in petals of carnation flowers treated with 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS). In petals of the transgenic carnation flowers, treatment with exogenous ethylene caused accumulation of the transcript for CPase and in-rolling (wilting), whereas it caused no or little accumulation of the transcripts for ACC oxidase and ACC synthase and negligible ethylene production. In petals of the flowers treated with DPSS, the transcripts for ACC synthase and ACC oxidase were accumulated, but no significant change in the level of the transcript for CPase was observed. These results suggest that the expression of ACC synthase and ACC oxidase genes, which leads to ethylene production, is differentially regulated from the expression of CPase, which leads to wilting, in carnation petals.

Journal Article↗