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Biomedical subjects

Y Nishida

Publications and source records attributed to Y Nishida.

At least 307 records · Page 17Linked to original sources
PubMed1990

Induction of angiogenesis in chick yolk-sac membrane by polyamines and its inhibition by tissue inhibitors of metalloproteinases (TIMP and TIMP-2).

Treatment of yolk-sac membranes of 4-day-old chick embryos with spermine or spermidine resulted in angiogenesis in the membranes. The angiogenic activity of spermine was stronger than that of spermidine. Putrescine, polylysine and histamine did not induce angiogenesis in the membranes. Administration of putrescine, spermidine and spermine increased their respective levels in yolk-sac membranes, but no interconversion of these amines was observed. The increases in spermidine and spermine levels in yolk-sac membranes preceded induction of angiogenesis. The angiogenesis induced by spermine was inhibited by tissue inhibitors of metalloproteinases, that is, TIMP and TIMP-2. These findings suggest that spermine and spermidine are angiogenesis factors in yolk-sac membranes of chick embryos and that matrix metalloproteinases represented by collagenase are involved in their action.

Animals↗
PubMed1990

Tumor angiogenesis and polyamines: alpha-difluoromethylornithine, an irreversible inhibitor of ornithine decarboxylase, inhibits B16 melanoma-induced angiogenesis in ovo and the proliferation of vascular endothelial cells in vitro.

alpha-Difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase, inhibited B16 melanoma-induced angiogenesis in chick embryo chorioallantoic membrane and subsequently the growth of the tumor on the chorioallantoic membrane. These inhibitions were reversed by exogenous putrescine and spermidine. DFMO also inhibited rapid neovascularization in yolk sac membrane of 4-day-old chick embryos and the inhibition was reversed by exogenous putrescine and spermidine. DFMO strongly inhibited DNA synthesis and proliferation of bovine pulmonary artery endothelial (BPAE) cells in culture and decreased their ornithine decarboxylase activity and intracellular polyamine concentrations. Addition of putrescine to the culture medium of DFMO-treated BPAE cells restored their intracellular putrescine and spermidine concentrations and their DNA synthesis and proliferation. Addition of spermidine to cultures of DFMO-treated BPAE cells restored their intracellular spermidine concentration and their DNA synthesis and proliferation. DFMO inhibited the proliferation of B16 melanoma cells in culture but the inhibitory effect was much less than that on BPAE cells. When one-half the monolayer of confluent cultures of BPAE cells had been peeled off, addition of DFMO to the cultures inhibited the proliferation and extension of the BPAE cells into the vacant area but had no effect on stationary cells in the remaining half of the monolayer, suggesting that it inhibited induction of proliferation of endothelial cells. These findings suggest that the antitumor activity of DFMO against solid tumors is probably due more to its inhibition of tumor-induced angiogenesis by inhibition of proliferation of endothelial cells induced by polyamine depletion than to a direct effect on tumor cell proliferation.

Animals↗
PubMed1990

[Preoperative chemotherapy and anti-cancer effect of gastric carcinoma].

For the purpose of the study of macroscopical and histopathological anti-cancer effects, preoperative cancer chemotherapy was performed in 31 cases with gastric carcinoma. Gastric carcinoma with preoperative chemotherapy showed advanced cancer in 15 cases, and early cancer in 16 cases. During preoperative chemotherapy, the drug 5-Fu or 5'-DFUR was administered orally. The results were as follows; i) Macroscopical change of early cancer cases with anti-cancer chemotherapy showed the onset and healing of ulceration in the cancerous lesion and the change of granular pattern in the IIc floor. ii) Early cancer cases had a multi-centric histopathological anti-cancer effect which showed regenerative epithelium in the cancerous lesion. iii) The extent of the histopathological anti-cancer effect in advanced carcinoma showed greater in the deep layer of cancer invasion. Consequently, morphological changes of early cancer cases with chemotherapy are similar to the cases without chemotherapy. The onset of cancer damage in advanced carcinoma is in the cancer invasive zone, deep layer.

Administration, Oral↗
PubMed1990

A new approach to determine the stereospecificity in lipase catalysed hydrolysis using circular dichroism (CD): lipases produce optically active diglycerides from achiral triglycerides.

We describe a sensitive CD method for determining the stereospecificity in lipase (E.C.3.1.1.3) catalysed hydrolysis of triacyl glycerols into diacyl glycerols. The diglycerols were converted to chiral tert-butyldimethylsilylated 1,2- or 2,3-di-O-benzoyl-sn-glycerol (5 or 5'), and their CD was measured. This approach showed for the first time that lipases produce optically active diacyl glycerides from achiral tripalmitin and tribenzoyl glyceride with a variable extent of enantioselectivity depending on the acyl groups and the enzymes.

Benzyl Alcohols↗
PubMed1990

Growth-inhibitory effects of 1,25-dihydroxyvitamin D3 on normal human keratinocytes cultured in serum-free medium.

The effect of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on the growth of normal human keratinocytes cultured in serum-free medium was investigated. 1,25(OH)2D3 inhibited the cell growth at 10(-7) M by 75.3% and at 10(-6) M almost completely. The growth inhibition was accompanied by changes related to proliferation: (1) remarkable inhibition of DNA synthesis, (2) the decrease in the number of high-affinity receptors for epidermal growth factor, with almost no change in total receptor number, (3) the rapid decrease in c-myc mRNA level. The inhibition of DNA synthesis and the decrease of c-myc mRNA expression occurred at 3 h after the addition of 1,25(OH)2D3. These results suggest that decrease of c-myc mRNA expression is one of the primary effects of 1,25(OH)2D3 in the growth inhibition of human keratinocytes.

Blotting, Northern↗
PubMed1990

Hypoxanthine guanine phosphoribosyltransferase deficiency: nucleotide substitution causing Lesch-Nyhan syndrome identified for the first time among Japanese.

A previously undescribed nucleotide substitution at codon 51 (CGA to TGA) has been identified using the polymerase chain reaction technique in hypoxanthine guanine phosphoribosyltransferase (HPRT) cDNA; this is the first molecular evidence for a point mutation in a Japanese patient with Lesch-Nyhan syndrome. The present mutation is the 19th nucleotide substitution identified as a germ-line mutation at this locus and the second mutation generating a stop codon. The position of the nucleotide substitution is exactly the same as a previously described mutation HPRTToronto, indicating for the first time that nucleotide substitutions at the same position in the sequence of HPRT can generate different mutant alleles, one causing a partial deficiency and the other a complete deficiency. Although the type of nucleotide substitution is different between the two cases, a single base position has twice become the target of a mutation. However, the calculation of the probability of finding substitution mutations at the same base position in the coding region of hprt indicates that there is no evidence for the presence of a hot spot for substitution mutations in the human hprt germ line.

Adolescent↗
PubMed1990

Ependymoma diagnosed in the first year of life in Japan in collaboration with the International Society for Pediatric Neurosurgery.

During 1987, 23 survey forms for ependymoma cases diagnosed in the 1st year of life were selected from 88 neurosurgical institutes in Japan in collaboration with the International Society for Pediatric Neurosurgery. There were no specific perinatal episodes. The most common clinical manifestations were symptoms of intracranial hypertension and hydrocephalus. Two of seven children with infratentorial ependymomas were alive, and all of the children with such supratentorial tumors were still alive. Of those with ependymoma, three of four in the total extirpation group, and three of seven in the subtotal or partial removal group were alive. The 1-year survival rate was 54% for ependymoma and 58.3% for ependymoblastoma. For 36% of the cases with ependymoma and 14.6% with ependymoblastoma, a 2-year survival rate was observed. Since the prognosis of these tumors is poor, they should be extirpated as often as possible. Collins' law held true in approximately half of the cases.

Brain Neoplasms↗
PubMed1990

Leucine-rich repeats and carboxyl terminus are required for interaction of yeast adenylate cyclase with RAS proteins.

A Saccharomyces cerevisiae gene encoding adenylate cyclase has been analyzed by deletion and insertion mutagenesis to localize regions required for activation by the Sa. cerevisiae RAS2 protein. The NH2-terminal 657 amino acids were found to be dispensable for the activation. However, almost all 2-amino acid insertions in the middle 600 residues comprising leucine-rich repeats and deletions in the COOH-terminal 66 residues completely abolished activation by the RAS2 protein, whereas insertion mutations in the other regions generally had no effect. Chimeric adenylate cyclases were constructed by swapping the upstream and downstream portions surrounding the catalytic domains between the Sa. cerevisiae and Schizosaccharomyces pombe adenylate cyclases and examined for activation by the RAS2 protein. We found that the fusion containing both the NH2-terminal 1600 residues and the COOH-terminal 66 residues of the Sa. cerevisiae cyclase rendered the catalytic domain of the Sc. pombe cyclase, which otherwise did not respond to RAS proteins, activatable by the RAS2 protein. Thus the leucine-rich repeats and the COOH terminus of the Sa. cerevisiae adenylate cyclase appear to be required for interaction with RAS proteins.

Adenylyl Cyclases↗
PubMed1990

Growth-inhibitory effects of 1,25-dihydroxyvitamin D3 on normal and psoriatic keratinocytes.

The effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the growth and DNA synthesis of cultured human keratinocytes obtained from involved and uninvolved psoriatic epidermis and normal epidermis were studied. Treatment with 10(-8) M and 10(-7) M of 1,25(OH)2D3 inhibited cell growth as follows: 58.5 +/- 19.3% and 21.3 +/- 13.6% in normal keratinocytes (n = 6); 43.8 +/- 22.8% and 17.8 +/- 12.3% in psoriatic uninvolved keratinocytes (n = 4); 51.7 +/- 18.2% and 13.2 +/- 6.4% in psoriatic involved keratinocytes (n = 6). Inhibition was virtually complete at 10(-6) M. DNA synthesis was also inhibited by 10(-8) M, 10(-7) M and 10(-6) M of 1,25(OH)2D3 as follows: 70.0 +/- 8.3%, 59.0 +/- 6.8% and 16.7 +/- 4.0%, respectively, in normal keratinocytes (n = 3); 78.5 +/- 13.5%, 51.5 +/- 25.5% and 24.5 +/- 21.5%, respectively, in psoriatic uninvolved keratinocytes (n = 2); and 69.3 +/- 14.5%, 41.3 +/- 19.1% and 14.8 +/- 11.2%, respectively, in psoriatic involved keratinocytes (n = 4). These results indicate that 1,25(OH)2D3 functions as a growth inhibitor for cultured human keratinocytes derived from both normal and psoriatic skin.

Calcitriol↗
PubMed1990

Cloning and nucleotide sequence of cDNA for Ki antigen, a highly conserved nuclear protein detected with sera from patients with systemic lupus erythematosus.

Patients with systemic lupus erythematosus (SLE) produce autoantibodies against a variety of nuclear antigens including Ki antigen. Although anti-Ki autoantibodies were found in a significant number of SLE patients, the nature of Ki antigen is poorly characterized. By using anti-Ki serum as a probe we have cloned a bovine cDNA directing the synthesis in Escherichia coli of a polypeptide immunologically indistinguishable from the authentic Ki antigen. A homologous human cDNA was also cloned and its nucleotide sequence predicted the entire primary structure of a novel nuclear protein with a molecular weight of 29 508 and with highly hydrophilic and weakly acidic character. The gene is highly conserved not only in the coding region but also in the 3'-untranslated region. The bacterially produced Ki antigen would be valuable for diagnosis of SLE.

Amino Acid Sequence↗
PubMed1990

Drosophila proliferating cell nuclear antigen (cyclin) gene: structure, expression during development, and specific binding of homeodomain proteins to its 5'-flanking region.

The genomic and cDNA clones for a Drosophila melanogaster proliferating cell nuclear antigen (PCNA) (cyclin) were isolated and sequenced. The coding sequence for a 260-amino-acid residue polypeptide was interrupted by a single short intron of 60 base pairs (bp), and about 70% of the deduced amino acid sequence of the Drosophila PCNA was identical to the rat and human PCNA polypeptides, with conserved unique repeats of leucine in the C-terminal region. Genomic Southern blot hybridization analysis indicates the presence of a single gene for PCNA per genome. The PCNA mRNA was detected at a high level in adult ovaries, unfertilized eggs, and early embryos and at low levels in the other developmental stages. The major transcription initiation site (cap site) was localized at 89 bp upstream from the ATG codon. Neither a TATA box nor a CAAT box was found within the 600-bp region upstream of the cap site. Clusters of 10 bp of sequence similar to the binding sites for Drosophila proteins containing homeodomains were found in the region from -127 to -413. DNase I footprint analysis revealed that the Drosophila homeodomain proteins coded by even-skipped and zerknüllt genes can specifically bind to these sites. These results suggest that the expression of the PCNA gene is under the control of genes coding for homeodomain proteins.

Amino Acid Sequence↗
PubMed1990

In vivo biological response to recombinant interferon-gamma during a phase I dose-response trial in patients with metastatic melanoma.

Interferon-gamma (IFN gamma), as produced by recombinant DNA technology, has shown a wide range of immunomodulatory activity in vitro and in vivo. Clinical studies have attempted to establish a dose-response relationship to define optimal dosage ranges for induction of effector cell function and host response in patients with cancer. We conducted a randomized trial to test the in vivo biologic activity of five daily dosages ranging from 3 to 3,000 micrograms/m2, administered by daily 2-hour bolus injection or by continuous infusion for 14 days. We demonstrate comparable immunobiologic effects of recombinant IFN gamma (rIFN gamma; Biogen, Inc, Cambridge, MA) administered by these two schedules at the various dosages tested, and have defined a relationship of dose to biologic response over this 3-log10 dose range. Oligo 2'5' adenylate synthetase (2'5'As) induction, natural-killer (NK) cell activity, and T-cell subset distribution (heightened T helper/suppressor ratio) showed the most consistent treatment-associated changes and the greatest immunobiologic effects at dosages of 300 to 1,000 micrograms/m2. Mononuclear cell DR and DQ antigen expression showed no consistent dose-related treatment effect. The relevance of the phenotypic, functional, and enzymologic effects observed in this trial to any clinical antitumor effects of IFN gamma in cancer therapy must now be established.

2',5'-Oligoadenylate Synthetase↗
PubMed1990

Prevalence and distribution of bovine coccidia in Japan.

A field survey was carried out on prevalence of bovine coccidia in 9 prefectures of Japan in the autumn of 1985. A total of 1,015 fecal samples was obtained from dairy and beef cattle more than 2 weeks old. Coccidial oocysts were found in 59.0% of all the samples examined. There were no significant differences in the prevalence between dairy and beef cattle of the same age group. The prevalence was the highest in the animals between 6 and 11 months old and decreased to 25% in those more than 24 months old. In the majority of the samples positive for oocysts, OPG (the number of oocysts per gram of feces) was less than 200. No clinical coccidiosis was found except in a few cases. Eleven Eimeria and one Isospora species were identified. Of these species, E. bovis and E. ellipsoidalis were the most prevalent, followed by E. aubrunensis, E. brasiliensis, and E. cylindrica in all the prefectures. The other species identified were E. canadensis, E. alabamensis, E. zuernii, E. wyomingensis, E. bukidnonesis, E. subspherica, and Isospora sp. in the order of frequency. Isospora sp. will be a pseudoparasite caused by the contamination with feces of passerine birds.

Age Factors↗
PubMed1990

Effects of brain natriuretic peptide on hemodynamics and renal function in dogs.

A new natriuretic peptide has been found in the porcine brain and termed brain natriuretic peptide (BNP). To examine the effects of BNP on the cardiovascular system and kidney as compared with alpha-hANP (ANP), BNP, and ANP (33, 167, 667 pmol/kg) were intravenously administered to anesthetized dogs. BNP dose-dependently decreased arterial pressure and left atrial pressure and dose-dependently increased heart rate, cardiac output, renal blood flow, urine volume, and sodium excretion. These effects were not significantly different from the effects of respective doses of ANP. To eliminate the possibility that these results were confounded by opposing actions of the baroreflex system, we performed additional experiments following sinoaortic denervation and vagotomy. These results also demonstrated no differences between the effects of BNP and ANP on the measured variables. Finally, we determined that the pharmacokinetics of exogenously injected BNP and ANP are indistinguishable. These findings lead to the possibility that BNP physiologically works in the body in the same manner as ANP.

Analysis of Variance↗
PubMed1990

Multiple cerebral and pulmonary arteriovenous malformations in association with brain and subcutaneous abscesses: a possible variant of hereditary hemorrhagic telangiectasia--case report.

The authors present a case in which multiple cerebral and pulmonary arteriovenous malformations (AVMs), a brain abscess, and a recurrent subcutaneous abscess were found concurrently in a 52-year-old male. He was admitted to our hospital for evaluation of a subcutaneous abscess in the right nuchal area and a right occipital AVM that had been detected at another hospital. Of his eight siblings, three had died of cerebrovascular disease (one in childhood and two as young adults), one had died of unknown causes in childhood, one had been hemiplegic since infancy, one had recently undergone removal of a pulmonary AVM, one was killed in World War II at the age of 24 years, and the remaining sibling was healthy. He had had surgery for a right occipital brain abscess three years prior to this admission. A general examination revealed no abnormalities other than the painful right nuchal mass. Neurological evaluation disclosed left homonymous hemianopsia, which was probably a result of his previous surgery for the right occipital brain abscess. Cerebral angiography showed AVMs in the right parietal (2 x 2 cm), right occipital (1.5 x 1.5 cm), and right cerebellar areas (1 x 1 cm). Digital subtraction angiography of the lung revealed multiple bilateral AVMs. The cerebral and pulmonary AVMs were removed in a two-stage operation. Although this case did not correspond precisely to the triad of hereditary hemorrhagic telangiectasia (HHT), the authors consider it to be related to HHT, since that syndrome is often complicated by multiple cerebral and pulmonary AVMs.

Abscess↗
PubMed1990

[A progressive gastric cancer in which preoperative oral chemotherapy resulted in a histopathological "Grade 2" rating].

This paper describes a case of a Borrmann type 3 gastric cancer, in which the preoperative intermittent oral administration of 5'-DFUR over a short term resulted in a histopathological rating of Grade 2. A 56-year-old man preoperatively received an intermittent, oral administration of 5'-DFUR, 2, 100 mg/day. An upper gastrointestinal series and endoscopy revealed macroscopically an extremely slight remission. Histopathologically, however, a widespread, remarkable degeneration of cancer cells and fibrinogenesis of the framework were observed, these results leading to a change of rating to Grade 2.

Adenocarcinoma↗