Search PubMed⌕ Search

Biomedical subjects

S Abe

Publications and source records attributed to S Abe.

At least 343 records · Page 19Linked to original sources
PubMed1997

Measurement of histidinohydroxylysinonorleucine and hydroxyproline in skin collagen by reversed-phase high-performance liquid chromatography after 9-fluorenylmethyl chloroformate labeling.

A novel, highly sensitive method to quantify histidinohydroxylysinonorleucine (HHL), a trifunctional type of cross-link in skin collagen, was developed. HHL in skin hydrolysates labeled with 9-fluorenylmethyl chloroformate (FMOC-Cl) was separated by reversed-phase high-performance liquid chromatography. Mass spectrometric analysis revealed that two FMOCs were bound to two primary amino acid residues, histidine and hydroxylysine, but not to lysine residue in one HHL molecule. Hydroxyproline was simultaneously measured to express the molar ratio of HHL to collagen. The detection range of HHL was from 1 to 10 pmol and that of hydroxyproline from 1 to 50 pmol. A 6-mm punch-biopsied human skin sample contained 0.40 to 0.69 mol of HHL per one molecule of collagen. This sensitive method is useful as it is rapid and can be used to examine the aging process or the change of HHL content in skin collagens of various pathologic states.

Chromatography, High Pressure Liquid↗
PubMed1997

Stretch-induced hypertrophic growth of cardiocytes and processing of brain-type natriuretic peptide are controlled by proprotein-processing endoprotease furin.

When hypertrophic growth is induced in neonatal rat cardiocytes by stretching, the cardiocytes express high levels of brain-type natriuretic peptide (BNP) and the proprotein-processing enzyme furin. A BNP precursor, gammaBNP, possesses a furin-cleavable Arg-X-X-Arg motif, which is cleaved when gammaBNP is processed to form BNP-45. The Arg-X-X-Arg motif is found in many precursors of growth factors and growth-related proteins. To determine if furin converts gammaBNP to BNP-45 as well as other unidentified growth-promoting protein precursors to their active form that may induce hypertrophic growth in cardiocytes, we used two protease inhibitor systems, synthetic peptidyl chloromethyl ketones (CMK) (dec-Arg-Val-Lys-Arg-CMK and dec-Phe-Ala-Lys-Arg-CMK; where dec is decanoyl) and vaccinia vector-integrated native and variant alpha1-antitrypsins. The furin-specific inhibitors, dec-Arg-Val-Lys-Arg-CMK and variant alpha1-antitrypsin with the inhibitory determinant Arg-X-X-Arg, suppressed the stretch-induced hypertrophic growth of cardiocytes as well as the processing of gammaBNP to BNP-45. The other serine protease inhibitors and variant alpha1-antitrypsin against elastase, or thrombin, however, neither suppressed the hypertrophic growth nor prevented the processing of gammaBNP to BNP-45. Thus, we suggest that furin catalyzes the conversion of gammaBNP to BNP-45 as well as growth-promoting proproteins to their active form, which might induce hypertrophic growth in cardiocytes.

Animals↗
PubMed1997

Aortic medial necrosis with or without thrombosis in rabbits treated with Russell's viper venom and angiotensin II.

The aim of the present study is primarily to re-examine an animal model of acute myocardial infarction (AMI) and arterial thrombosis, developed by Constantinides and his colleagues in the 1960s, in both heritable hyperlipidemic rabbits and normal rabbits because they did not study these rabbits. The groups in this study consisted of 29 normal rabbits and 29 Watanabe heritable hyperlipidemic (WHHL) rabbits. These rabbits were administered Russell's viper venom (RVV) as a procoagulant, intraperitoneally with serotonin or angiotensin II or saline, intravenously. As a control, 10 normal and 17 WHHL rabbits were administered intravenously with either angiotensin II or saline. These treatments were given on 2 successive days. AMI lesion was found in 8 of 29 normal and 7 of 29 WHHL rabbits receiving RVV and angiotensin or serotonin. Angiotensin II promoted the incidence of aortic thrombosis associated with segmental medial necrosis and an intimal disruption in WHHL rabbits receiving RVV. In the normal rabbits, angiotensin II in addition to RVV induced segmental medial necrosis of the aorta, but angiotensin II alone did not. Thus, we postulated that a synergistic effect of RVV as a cytotoxic substance and a sudden increase in the aortic wall tension by angiotensin II might thus result in acute aortic medial necrosis. The conclusion was that no close correlation between coronary arteriosclerosis and AMI was found in this animal model. The intravenous administration of angiotensin promoted aortic medial necrosis even in normal rabbits treated with RVV and then accelerated aortic thrombosis in the WHHL rabbits treated with RVV.

Angiotensin II↗
PubMed1997

Nitric oxide contributes to the progression of myocardial damage in experimental autoimmune myocarditis in rats.

BACKGROUND: Excess amounts of NO produced by an inducible NO synthase (iNOS) in response to cytokines may be cytotoxic and can be destructive to tissue. We investigated the role of NO in the development of myocardial damage and the effects of aminoguanidine (AG), an inhibitor of iNOS, on experimental autoimmune myocarditis in rats. METHODS AND RESULTS: Autoimmune myocarditis was induced in 20 Lewis rats by injection of porcine cardiac myosin. Ten of the 20 rats were administered AG. The severity of myocarditis was evaluated by measuring the size of myocarditic lesion and serum levels of CK-MB. Serum NO levels were determined using the Cd/Cu method. Tissue specimens were immunohistochemically examined for iNOS and nitrotyrosine. Histopathological study revealed extensive myocardial destruction and massive inflammatory cell infiltration in AG-untreated rats but only focal mononuclear cell infiltration in AG-treated rats. The mean percent areas of inflammatory lesions in the untreated and treated rats were 56 +/- 13% and 3 +/- 2%, respectively (P < .001). NO levels were 102 +/- 23 and 25 +/- 9 IU/L, respectively (P < .01). CK-MB levels were 68 +/- 13 and 16 +/- 13 nmol/L, respectively (P < .01). Superoxide production as measured with an ex vivo monitoring system was also significantly decreased in the treated rats. Nitrotyrosine relating to the generation of peroxynitrite was detected through immunostaining in the inflammatory lesions of untreated rats but not in those of treated rats. CONCLUSIONS: Excess amounts of NO produced by iNOS appear to contribute to the progression of myocardial damage in myocarditis. AG may prove to be useful in the treatment of myocarditis.

Animals↗
PubMed1997

Surgically curable and incurable scirrhous carcinomas of the stomach.

BACKGROUND AND OBJECTIVES: The purpose of this study was to identify a subgroup of patients with scirrhous carcinoma of the stomach who are more suitable for surgery by analysis of their clinicopathologic characteristics. METHODS: Seventy-three patients with scirrhous gastric carcinoma who underwent gastrectomy between 1979 and 1994 were included in the study. Clinicopathological characteristics of 5-year survivors and nonsurvivors were compared. A multivariate analysis of various prognostic factors was performed. RESULTS: The 5-year survival rate was 31.4%; 78% (28/36) of nonsurvivors died of malignant ascites and only 8% (3/36) died of hepatic or lung metastasis. When clinicopathologic parameters of 5-year survivors and nonsurvivors were compared, age, tumor size, macroscopic appearance, pT, pN, pM, stage, peritoneal lavage cytology, residual tumor, extent of gastric resection, operation time, volume of blood loss, and transfusion were significantly different. By the multivariate analysis, residual tumor, pathological depth of tumor infiltration, blood transfusion, and histological type were the independent prognostic factors. CONCLUSIONS: The prognosis of scirrhous carcinoma of the stomach is mainly determined by the depth of penetration and curability. In order to obtain better survival, early detection of tumor while it is limited to T2 stage appeared most important. Aggressive surgery would be indicated for T3 tumors, but in the case of T4 tumors, extent of operation should be determined by other factors such as extent of nodal metastasis or presence of distant metastasis.

Adenocarcinoma, Scirrhous↗
PubMed1997

In vitro and in vivo modulation by rhizoxin of non-P-glycoprotein-mediated vindesine resistance.

Rhizoxin is an antineoplastic drug that inhibits tubulin polymerization. In this study, we demonstrated that rhizoxin was approximately twice as active in vitro against a human small-cell lung cancer cell line with non-P-glycoprotein-mediated resistance to vindesine, H69/VDS, as against its parental line, H69. Tubulin polymerization in H69/VDS, demonstrated by Western blot analysis, was inhibited markedly by rhizoxin compared with that in H69, in a concentration-dependent manner. A drug-accumulation study showed that the intracellular rhizoxin level in H69/VDS was 15% lower than that in H69, whereas efflux from H69/VDS was enhanced slightly. These results indicate that enhanced inhibition of tubulin polymerization rather than increased intracellular drug concentration accounted for the higher sensitivity of H69/VDS to rhizoxin. In an experiment using mice with severe combined immunodeficiency and inoculated subcutaneously with H69/VDS, in vivo tumor growth was reduced markedly by three intermittent intraperitoneal doses of rhizoxin compared with that in mice inoculated with H69. Three weeks after the last rhizoxin dose, the relative treated/untreated tumor volumes were 0.29 for H69, but only 0.06 for H69/VDS, indicating that H69/VDS regrowth was minimal even after a 3-week treatment-free period. In conclusion, rhizoxin conquers vindesine resistance of a human small-cell lung cancer cell line in vitro and in vivo.

Animals↗
PubMed1997

Elevated levels of type II soluble tumor necrosis factor receptors in the bronchoalveolar lavage fluids of patients with sarcoidosis.

Since tumor necrosis factor (TNF) is known to be involved in granuloma formation in sarcoidosis, and soluble TNF receptors (sTNF-Rs) inhibit TNF action in vivo, we evaluated the levels of sTNF-Rs in the bronchoalveolar lavage fluids (BALF) of 31 subjects using an enzyme-linked immunosorbent assay. Our group consisted of 13 patients with sarcoidosis (7 sarcoidosis patients who received no treatment and 6 who received corticosteroid therapy) and 18 control subjects (11 healthy nonsmokers and 7 asymptomatic smokers). Type II (75-kDa), but not type I (55 kDa) sTNF-R in BALF was elevated significantly in patients with sarcoidosis compared with the healthy nonsmokers (type I: 126.7 +/- 17.6 pg/ml BALF vs 79.4 +/- 16.5 pg/ml BALF, p > 0.05; type II: 98.3 +/- 27.8 pg/ml BALF vs 26.7 +/- 4.9 pg/ml BALF, p < 0.05). Although levels of type I sTNF-R in BALF from sarcoidosis patients were not correlated with any cellular profiles of BALF, concentrations of type II correlated significantly with the numbers of lymphocytes in BALF. We concluded that sTNF-R is a normal constituent of the epithelial lining fluids and that levels of type II sTNF-R are elevated significantly in the BALF from individuals with sarcoidosis. This suggests that sTNF-Rs may influence the local bioactivity of TNF and may also contribute to the pathogenesis of sarcoidosis.

Antigens, CD↗
PubMed1997

Uniparental chromosome elimination in the early embryogenesis of the inviable salmonid hybrids between masu salmon female and rainbow trout male.

Chromosome elimination through chromosome loss and partial deletion is known to be one of the causes of embryonic inviability in some salmonid interspecific hybrids. Using fluorescence in situ hybridization and related techniques, including whole chromosome painting and comparative genomic hybridization, parental origin of eliminated chromosomes was identified in the inviable hybrids between masu salmon (Ms, Oncorhynchus masou) female and rainbow trout (Rb, O. mykiss) male at the early embryonic stage prior to death. In these hybrids, the haploid Rb chromosome number decreased to nearly half, whereas the Ms chromosomes were retained as one or occasionally two full haploid complements. The Rb chromosomes were also involved in the frequently observed fragments and micronuclei. Whereas the occurrence of fragments was constant throughout the observed period, chromosome loss occurred mainly from just after fertilization to the blastulae stage. In tissue sections and cell spreads of late blastula, some Rb chromosomes were trapped in the midzone from ana- to telophase, resulting in micronuclei at the subsequent interphase. Micronuclei and mitotic abnormalities were also observed in the androgenetic haploid hybrids. However, such abnormalities were seldom or never observed in the viable reciprocal hybrids. The present findings suggest that the paternal Rb chromosomes in the inviable hybrids are preferentially eliminated through mitotic abnormalities during early embryogenesis, owing to a possible incompatibility between the maternal Ms cytoplasm and paternal Rb genome.

Animals↗
PubMed1997

Establishment of a new continuous clear cell sarcoma cell line. Morphological and cytogenetic characterization and detection of chimaeric EWS/ATF-1 transcripts.

Clear cell sarcoma (CCS), a rare tumour of deep soft tissues, often has a t(12; 22) (q13; q12) translocation that induces the formation of a hybrid EWS/ATF-1 gene. To investigate these alterations further, we established a new continuous cell line directly from a CCS taken from a 9-year-old girl. The cultures were characterized with respect to morphological, ultrastructural, immunohistochemical and karyotypical features and were tested by reverse transcription PCR (RT-PCR) for chimaeric EWS/ATF-1 transcripts. The continuous cell line, designated KAO, is tumorigenic in nude mice, and the resultant tumours resemble the primary CCS. The tumour cells and the cultured cells have melanosomes in their cytoplasm and are immunoreactive with the melanoma-specific antibody HMB45, but do not express S-100 protein. The cultured CCS cells have the t(12; 22)(q13; q12) translocation and express the hybrid EWS/ATF-1 gene. No transcripts of the hybrid gene were detected in a malignant cutaneous melanoma tested simultaneously. Although CCS and malignant melanoma are morphologically related, the present results suggest that their geneses differ at the chromosome and molecular levels. They also indicate that chromosome analysis and detection of fusion EWS/ATF-1 transcripts may be useful adjuvant tools for the diagnosis of CCS.

Activating Transcription Factor 1↗
PubMed1997

Clinicopathological features of superficial squamous cell carcinoma of the esophagus.

BACKGROUND: The depth of penetration is the crucial factor determining the prognosis of esophageal carcinoma patients. Patients with superficial esophageal carcinoma have a significantly favorable clinical course compared with those with advanced cancers. The outcome for patients with mucosal cancer is excellent with a 5-year survival rate exceeding 80%. On the other hand, submucosal cancer often metastasizes to lymph nodes or other organs, and the prognosis of these patients is far from satisfactory. METHODS: Among 165 patients with squamous cell carcinoma of the esophagus, surgically resected between December 1979 and April 1995, 30 patients (18.2%) had superficial esophageal carcinoma (SEC) confined to the epithelium, lamina propria mucosa, or submucosa. Disease profile and clinicopathological characteristics of these 30 patients were studied. RESULTS: The incidence of SEC has increased from 6.3% (2 of 32) in the first 5-year period (1979 to 1984) to 27.4% (20 of 73) in the recent 5-year period (1991 to 1995). Subjective symptoms were present in 2 (13.3%) with 15 mucosal cancers and in 4 (26.7%) with 15 submucosal cancers. The remaining 24 patients (80%) had no subjective symptoms. Twenty-two patients (73.3%) were diagnosed to have the lesions by endoscopic examination at the time of screening for gastric problems, and only 3 were detected by gastrointestinal series. None of the 15 patients with mucosal cancer had lymphatic invasion, venous invasion, or lymph node metastasis. On the other hand, in those with submucosal cancers, 9 (60%) had lymphatic invasion, 5 (33.3%) venous invasion, and 8 (53.3%) lymph node metastases. Twenty-two patients are alive without recurrence. The 3- and 5-year survival rates are 86.7% and 86.7% for patients with mucosal cancer and 72.2% and 65.0% for those with submucosal cancer, respectively. CONCLUSION: Esophagectomy with wide lymphadenectomy should be carried out for submucosal cancer, whereas esophagectomy with moderate lymphadenectomy can be preferred for mucosal cancer.

Carcinoma, Squamous Cell↗
PubMed1997

Use of the QRS scoring system in the early estimation of myocardial infarct size following reperfusion.

While the QRS scoring system has been established as a convenient tool for estimating infarct size in nonreperfused patients during the chronic stage of myocardial infarction, its applicability to reperfused patients in the acute stage has not been established. To investigate whether infarct size could be estimated by the QRS scoring system soon after reperfusion, we evaluated QRS scores obtained serially 6 hours to 1 month after reperfusion, total creatine kinase release, and left ventricular ejection fraction in 126 patients with acute myocardial infarction who underwent successful reperfusion therapy. A significant correlation was observed between the QRS score obtained after 6 hours and that obtained after 1 month (r = .89). The QRS scores obtained after 6 hours and 1 month were significantly correlated with total creatine kinase release (r = -.65 and r = -.75, respectively) and left ventricular ejection fraction (r = .62 and r = .76, respectively). Thus, the QRS scoring system can be used as a simple and economical method for estimation of infarct size soon after reperfusion.

Aged↗
PubMed1997

Immunohistochemical studies on EGF family growth factors in normal and ulcerated human gastric mucosa.

Expression of members of the epidermal growth factor family, including epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha), amphiregulin (AR), and Cripto, as well as their putative receptor, epidermal growth factor receptor (EGFR), was studied immunohistochemically in human gastric mucosa to evaluate their possible roles in cell proliferation of normal and regenerative gastric mucosa. We also examined the correlation betwen cell proliferation and EGFR by double immunohistochemical staining for proliferating cell nuclear antigen (PCNA) and EGFR. In normal gastric mucosa, TGF-alpha, Cripto, and AR immunoreactivities were observed in the surface epithelial and parietal cells of gastric fundic glands, respectively. EGF immunoreactivity was not observed in any of normal mucosa examined. EGFR immunoreactivity was detected on foveolar cells in proliferative zones and in parietal cells. Double immunostaining revealed that EGFR immunoreactivity was distributed much more widely than PCNA immunoreactivity. PCNA positive epithelial cells adjacent to gastric ulcer margin expressed relatively intense EGFR but did not express any of the growth factors examined. On the other hand, relatively intense immunoreactivity of both TGF-alpha and Cripto was detected in PCNA-negative regenerative epithelium located distant from gastric ulcer margin. Relative immunoreactivity of AR in regenerative gastric epithelium associated with ulcer was not different from that in normal gastric mucosa. TGF-alpha, AR, and Cripto are considered to play important roles in normal gastric mucosal proliferation, and TGF-alpha and Cripto may be involved in ulcer healing, possibly via a paracrine mechanism.

Amphiregulin↗
PubMed1997

Augmentation of production of TNF-alpha and anti-tumour activity by an amphotericin B preparation for clinical use in mice.

Effects of amphotericin B on production of endogenous tumour necrosis factor alpha (TNF-alpha) and anti-tumour activity in mice was examined. Intravenous administration of Fungizone, an amphotericin B preparation complexed with deoxycholate, augmented the induction of endogenous TNF in response to a second stimulus with intravenous doses of FK23 (heat-killed Enterococcus faecalis). This augmentation was observed when more than 1.8 microg of Fungizone was injected intravenously before intravenous dosing of FK23. The time interval between priming injection of Fungizone and secondary injection of FK23 for the maximal effect was 3 h. Similar augmentation of TNF production was also observed in amphotericin B-primed and FK23-injected mice. Correspondingly, anti-tumour activity of the combined, intravenous injection of Fungizone and FK23 with a 3-h interval was examined. Growth of Meth A fibrosarcoma was clearly inhibited by this combination but not by administration of either one alone. These results suggest that amphotericin B is able to elicit anti-tumour activity, perhaps through activation of the immune system, and in particular augmentation of the induction of endogenous TNF.

Amphotericin B↗
PubMed1997

Sex-related spatial kin structure in a spring population of grey-sided voles Clethrionomys rufocanus as revealed by mitochondrial and microsatellite DNA analyses.

Polymerase chain reaction-directed mitochondria (mt) and microsatellite DNA analyses were performed to examine the kin structure in a spring population of grey-sided voles Clethrionomys rufocanus in Hokkaido, Japan. The spatial distribution of 81 voles in a trapping grid (about 1 ha) was estimated by using the catch-mark-release method. DNA samples were extracted from the toes clipped for individual identification. Maternal lineages of voles were unequivocally determined by the mtDNA haplotypes, as identified by nucleotide sequencing of the control region. Relatedness between individuals was estimated based on the genotype and allele frequencies at several microsatellite loci. Although the distribution of voles was uniform within the grid, neighbouring females were frequently from the same maternal lineage. Relatedness values between females correlated negatively with geographical distances. Combination of the two molecular markers revealed four clusters of closely related, matrilineal females in the population, whereas no such cluster was apparent in males. The present study first demonstrated a sex-related spatial kin structure in a natural population of the grey-sided vole.

Animals↗