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O Nishimura

Publications and source records attributed to O Nishimura.

At least 55 records · Page 3Linked to original sources
PubMed1999

A small-molecule, nonpeptide CCR5 antagonist with highly potent and selective anti-HIV-1 activity.

The beta-chemokine receptor CCR5 is considered to be an attractive target for inhibition of macrophage-tropic (CCR5-using or R5) HIV-1 replication because individuals having a nonfunctional receptor (a homozygous 32-bp deletion in the CCR5 coding region) are apparently normal but resistant to infection with R5 HIV-1. In this study, we found that TAK-779, a nonpeptide compound with a small molecular weight (Mr 531.13), antagonized the binding of RANTES (regulated on activation, normal T cell expressed and secreted) to CCR5-expressing Chinese hamster ovary cells and blocked CCR5-mediated Ca2+ signaling at nanomolar concentrations. The inhibition of beta-chemokine receptors by TAK-779 appeared to be specific to CCR5 because the compound antagonized CCR2b to a lesser extent but did not affect CCR1, CCR3, or CCR4. Consequently, TAK-779 displayed highly potent and selective inhibition of R5 HIV-1 replication without showing any cytotoxicity to the host cells. The compound inhibited the replication of R5 HIV-1 clinical isolates as well as a laboratory strain at a concentration of 1.6-3.7 nM in peripheral blood mononuclear cells, though it was totally inactive against T-cell line-tropic (CXCR4-using or X4) HIV-1.

Amides↗
PubMed1999

Urotensin II is the endogenous ligand of a G-protein-coupled orphan receptor, SENR (GPR14).

Two molecular species of urotensin II (UII) were isolated from porcine spinal cords and identified as the endogenous ligands of a G-protein-coupled orphan receptor, SENR (sensory epithelium neuropeptide-like receptor), which is identical to GPR14. We established a CHO cell line stably expressing the rat SENR and investigated several tissue extracts to evoke the response mediated by the SENR. Extract from porcine spinal cords showed an activity of arachidonic acid metabolites release from SENR-expressing cells and was purified using HPLC. Two active substances were isolated and their sequences were determined as GPTSECFWKYCV and GPPSECFWKYCV, which were revealed to be porcine UII. Synthetic UII peptides caused arachidonic acid metabolites release activity in the rat SENR-expressing cells with an EC(50) value of 1 nM. Three cDNAs encoding the precursor proteins of porcine UII were cloned from a porcine spinal cord cDNA library; 2 consist of 121 amino acid residues and the other, which seemed to be a splicing variant, consist of 85 residues.

Amino Acid Sequence↗
PubMed1998

A prolactin-releasing peptide in the brain.

Hypothalamic peptide hormones regulate the secretion of most of the anterior pituitary hormones, that is, growth hormone, follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone and adrenocorticotropin. These peptides do not regulate the secretion of prolactin, at least in a specific manner, however. The peptides act through specific receptors, which are referred to as seven-transmembrane-domain receptors or G-protein-coupled receptors. Although prolactin is important in pregnancy and lactation in mammals, and is involved in the development of the mammary glands and the promotion of milk synthesis, a specific prolactin-releasing hormone has remained unknown. Here we identify a potent candidate for such a hormone. We first proposed that there may still be unknown peptide hormone factors that control pituitary function through seven-transmembrane-domain receptors. We isolated the complementary DNA encoding an 'orphan' receptor (that is, one for which the ligand is unknown). This receptor, hGR3, is specifically expressed in the human pituitary. We then searched for the hGR3 ligand in the hypothalamus and identified a new peptide, which shares no sequence similarity with known peptides and proteins, as an endogenous ligand. We show that this ligand is a potent prolactin-releasing factor for rat anterior pituitary cells; we have therefore named this peptide prolactin-releasing peptide.

Amino Acid Sequence↗
PubMed1998

Acute cocaine effects on stereotype and defense: an ethoexperimental approach.

Cocaine administration to laboratory animals may produce locomotor hyperactivity and stereotypies that include sniffing and rearing, in addition to anxiety-like effects. A time-sampling study of the effects of 3, 10 or 30 mg/kg cocaine (i.p.) over time following injection indicated early enhancement of locomotion and crouching, with the latter most increased in low- and intermediate-dose cocaine groups, with increased rearing and standing during the second hour of the test period. Additional analyses at 30-60 min post-injection suggested qualitative changes in rearing, with high dose animals showing more, but shorter, rears, and a higher frequency of sniffing. The high dose cocaine enhancement of sniffing was strongly associated with rear and stand behaviors, but also occurred while the animal was crouching. This pattern of changes, with initial crouching/freezing and locomotion (flight?), followed by rearing, standing, and sniffing behaviors similar to those seen in risk assessment suggests that cocaine, particularly at high doses, may elicit defense. An additional study using only saline or the high (30 mg/kg) dose indicated that cocaine produced more sniffing regardless of the direction from which the air stream entered the test cage (i.e. top or bottom). However, cocaine animals oriented their sniffing behaviors toward the incoming air, with reliably more sniffs up in cages with the air stream entering from the top, and more sniffs down, when the air stream entered through a wire mesh cage bottom. Controls showed the same pattern, but their sniff orientation differences were not reliable. These results indicate that the sniffing that follows acute high dose cocaine administration is appropriately oriented toward relevant environmental stimuli, a factor disconsonant with the interpretation of sniffing as a stereotypical behavior, but one that is in agreement with the view that it may reflect a risk assessment component of the defense pattern.

Aggression↗
PubMed1998

Synthesis of new peptides with prolactin-releasing activity by a combination of recombinant DNA technology and a cysteine-specific cyanylation reaction.

A newly isolated peptide from bovine hypothalamus with prolactin-releasing activity (prolactin-releasing peptide; PrRP) was synthesized by a combination of recombinant DNA technology and a cysteine-specific cyanylation reaction, together with rat and human homologs. The peptides were expressed in the form of fusion proteins with basic fibroblast growth factor mutein, which were purified by heparin-affinity chromatography. The fusion proteins were cleaved at the cysteine residues of the junction site by cyanylation, followed by treatment with ammonia for C-terminal amidation. Purification of the resulting crude peptides was performed using chromatography on a gel-filtration column, a cation-exchange column, and a reversed-phase column. As an example, about 90 mg of bovine PrRP (bPrRP) was obtained from 201 of culture bloth. The purified b PrRP showed full biological activities in binding to its receptor expressed on CHO cells and releasing arachidonic acid metabolite from the same cells, while the C-terminal acid form of bPrRP had little of these activities. These results indicate that the C-terminal amide structure is very important for expressing biological activity. The peptides obtained here might be very useful for studies on their biological significance and roles in vivo.

Amino Acid Sequence↗
PubMed1998

Renaturation of recombinant human neurotrophin-3 from inclusion bodies using a suppressor agent of aggregation.

Escherichia coli has been widely used in the production of recombinant proteins. One of the drawbacks inherent in this method is that the proteins produced in the cells often form inactive inclusion bodies. Usually, the inclusion bodies can be separated from other cell components, solubilized by denaturants such as guanidine hydrochloride or urea, and then renatured through a refolding process such as dilution or dialysis. However, it has been shown that biologically active recombinant human neurotrophin-3 cannot be obtained at high yield by this procedure due to aggregation and precipitation of the protein. We applied the refolding process using the aggregation suppressor L-arginine in the renaturation of neurotrophin-3, and obtained biologically active neurotrophin-3 at high yield from the inclusion bodies. Consequently, about 10 mg of purified neurotrophin-3 was prepared from 1 litre of culture broth.

Amino Acids↗
PubMed1997

Studies of polymorphic DNA fingerprinting and lipid pattern of Mycobacterium tuberculosis patient isolates in Japan.

Strain differentiation by DNA restriction fragment length polymorphism (RFLP) has been used mainly for the epidemiological purpose of Mycobacterium tuberculosis infection. In this study, we tried to connect the molecular and phenotypic characteristics of M. tuberculosis patient isolates by comparing the DNA fingerprints obtained by RFLP using IS6110 and lipid patterns using two-dimensional thin-layer chromatography (2-D TLC) with silica gel, since M. tuberculosis has a lipid-rich cell envelope which contributes to the virulence and immunomodulatory properties. We found that 66 isolates of M. tuberculosis from tuberculosis patients showed that the occurrence of IS6110 varied from 1 to 24 copies. The IS6110 patterns were highly variable among isolates. Fifty different RFLP patterns were observed, and 12 RFLP patterns were shared by two or more strains. By computerized analysis of the RFLP patterns of M. tuberculosis patient isolates, we found that 95% of the isolates fell into seven clusters, from A to G, with at least two isolates in each (> 30% similarity). Among the cellular lipids, the phospholipid composition did not differ by strain, whereas the glycolipid pattern differed markedly. Especially, the relative concentration of cord factor and sulfolipid, both of which were known as virulent factors, varied by strain. The fingerprints of some strains showed an association between the DNA and glycolipid patterns, even though some of the same DNA fingerprint strains showed differences in lipid patterns. Among the patient isolates, M. tuberculosis strain 249 possessed a specific glycolipid with 2-O-methyl-L-rhamnose and L-rhamnose, which is rarely found in other strains. This glycolipid showed serological activity against the sera of tuberculosis patients, even if the reactivity was not as strong as trehalose dimycolate. It also showed the inhibition of phagosome-lysosome fusion in macrophages, suggesting involvement with virulence. These results suggest that RFLP analysis using IS6110 is useful for clustering the human isolates of M. tuberculosis, however, for further strain differentiation on virulence, a lipid analysis provides more information.

Antibodies, Bacterial↗
PubMed1996

[Chest wall reconstruction after the resection of primary chest wall tumors].

Between April 1983 and June 1994, we performed chest wall reconstructions on 9 patients (7 males and 2 females) out of 27 all of whom underwent the radical resection for the primary chest wall tumors. Histological diagnosis of tumors included 6 chondrosarcomas, 1 Ewing's sarcoma, 1 plasmacytoma and 1 giant cell tumor. Six lesions were located on the rib and 3 on the sternum. For the materials for reconstruction of the chest wall use a polyethylene plate in 2 patients, a Marlex mesh in 5 patients and a Marlex mesh with a methyl methacrylate utilizing the sandwich method in 2 patients. The polyethylene plate proved to be satisfactory for maintaining stability of the chest wall. However, our experience using this plate showed intensive foreign body reactions, and discovering these we have not use the polyethylene plate. Marlex mesh had an affinity with human tissue and was very easy to use and produced no complications. We use Marlex mesh for flat surfaces on the anterior or posterior chest wall. Marlex mesh and methyl methacrylate utilizing the sandwich method, combined the solidity and shaping of methyl methacrylate with the benefit such as easy fixation and excellent incorporation of the mesh.

Adult↗
PubMed1996

[A case of Pryce's type I pulmonary sequestration with hemoptysis and bruit].

A 20-year-old man was admitted to our hospital with the complaint of hemoptysis. A bruit was best heard at the lower portion of the left posterior chest. CT scan and MRI revealed clearly the existence of a large aberrant vessel from the descending thoracic aorta. Aorto- and pulmonary arteriography demonstrated that a large systemic artery from the descending thoracic aorta supplied the basilar segments of the left lower lobe, and to which there was no pulmonary artery supply. The pulmonary veins from these segments drained into the left atrium. The properative diagnosis was Pryce's type I pulmonary sequestration. A left lower lobectomy was performed. The aberrant vessel was 15 mm in diameter and was elastic walled. The systemic artery of the basilar segments revealed proliferation of media and obstructive changes. Some discussions were made about hemoptysis and bruit in 23 cases of Pryce's type I pulmonary sequestration in Japan.

Adult↗
PubMed1995

Efficient production of anti-(hepatitis B virus) antibodies and their neutralizing activity in chimpanzees.

For industrial production of human monoclonal antibodies (hmAb) against hepatitis B virus surface antigen (HBsAg), we scaled-up a short-term perfusion culture in serum-free medium, which was chosen as the most suitable culture method, to a 50-1 fermentor equipped with a rotating shear filter. Using hydrophobic chromatography as the initial step of hmAb purification, the mAb HBW4, HBW6 and W471 were isolated in good quality from the respective culture broths in yields of approximately 75%. Each of the three purified hmAb alone, and a cocktail of the three, protected chimpanzees against HB virus, when injected intravenously 3 h after viral challenge, as long as the serum antibody levels were significant. A pharmacokinetic study using cynomolgus monkeys demonstrated that the hmAb have a long plasma half-life and bioavailability of approximately 76% upon intramuscular injection in primates. Thus, anti-HBsAg hmAb produced by an industrial process are expected to be successfully used in clinical fields.

Animals↗
PubMed1994

Production of human PTH(1-34) via a recombinant DNA technique.

The production of hPTH(1-34) by site specific chemical cleavage of [Cys35]hPTH(1-84) obtained by a biotechnology technique is described. The amino-peptide bond of S-cyanylated cysteine residues in peptides or proteins is specifically cleaved by exposure to an alkaline solution (Stark, G. R. (1977) Methods Enzymol, 47, 129-132). However, when applying this method to [Cys35]hPTH(1-84), we observed many by-products. Formation of these by-products was suppressed using a short reaction in 0.03N NaOH containing 6M urea at low temperature, and hPTH(1-34) was specifically produced. The product was indistinguishable from standard hPTH(1-34) with respect to chemical and biological characterization.

Amino Acid Sequence↗
PubMed1994

A novel procedure for the preparation of biologically active recombinant peptides using a cyanylation reaction.

A cysteine specific cleavage reaction was used for the preparation of biologically active peptides from recombinant fusion proteins. The fusion protein through cysteine was prepared by a recombinant DNA technology and then treated with cyanylating reagents such as 2-nitro-5-thiocyanatobenzoic acid (NTCB) and 1-cyano-4-(dimethylamino) pyridinium tetrafluoroborate (DMAP-CN) to release the desired product. As an example, we have selected a glucagon-like peptide 1 (7-37) (termed insulinotropin). We constructed an expression vector for a fusion protein in which insulinotropin and human basic fibroblast growth factor (hbFGF) mutein (abbreviated as CS 23) are connected by cysteine and then expressed it in Escherichia coli cells. The fusion protein, after refolding, was purified by heparin affinity chromatography, since CS23 has a strong affinity for heparin. The affinity-purified fusion protein was treated with NTCB or DMAP-CN to give crude insulinotropin, which was then purified by reversed phase (rp) high-performance liquid chromatography (HPLC). From various criteria such as amino acid analysis, amino acid sequence and the biological activity, the purified material obtained was found to be methionylated insulinotropin (Met-insulinotropin) with full activity. The specificity and simplicity of the present method make it versatile and convenient for the preparation of biologically active peptides.

Amino Acid Sequence↗
PubMed1994

[Neuroblastoma].

Explore the source record for details and available documents.

Diagnosis, Differential↗
PubMed1992

[Treatment of pericardial cyst under thoracoscopy].

Thoracoscopic therapy was carried out on two cases of pericardial cyst. The first patient was a 24-year-old male. An abnormal shadow on a chest X-ray was pointed out at a regular checkup. Thoracoscopy was carried out under the local anesthesia and a thin-walled cyst was discovered. The cyst was punctured and serous fluid was aspirated. Then, several biopsy specimens were obtained from the cyst wall, a pathological diagnosis of the cyst was made as a pericardial cyst. One year after the thoracoscopy, no abnormal shadow is observed on chest X-ray. The second patient was a 26-year-old male. It was also discovered that he had an abnormal shadow on a chest X-ray at a regular medical checkup. Since a solid mass couldn't be completely denied, thoracoscopy was carried out in preparing for thoracotomy under the general anesthesia. The cyst observed between SVC and the azygos vein, and serous fluid was aspirated form the cyst. Following this, the cyst wall was biopsied and opened. Since no cases of malignant pericardial cysts have been reported, an operation is not usually required for these patients. We suggest that thoracoscopy is very useful tool for the final diagnosis and therapy of pericardial cyst because this method is easily carried out under local anesthesia.

Adult↗
PubMed1990

Thymolipoma: a report of three cases.

Three cases of thymolipoma, seen in a 6 year old boy, a 34 year old woman and a 24 year old man are presented herein. The weight of each tumor was 1380 g, 670 g and 560 g respectively. The 2 male patients had no symptoms and the woman only complained of a fever. On CT scan the thymic tissue was recognized as islands of soft tissue density within a fatty mass, and T1 weighted MRI was helpful in demonstrating the predominant fatty nature of this tumor. Thus, our experience demonstrates that CT and MRI are valuable for establishing a diagnosis of thymolipoma. In a review of the literature on the subject, some clinical features of this non-malignant tumor in the mediastinum are discussed. Although rare, thymolipoma should be considered in the differential diagnosis of mediastinal tumors.

Adult↗
PubMed1990

[A case of giant thymolipoma in a child].

A case report of a giant thymolipoma in 6-year-old boy is reported. Following school screening, an abnormal shadow in the left chest was found on the chest X-ray. CT scan and MRI suggested the mediastinal tumor containing a fatty mass. The tumor was resected on bloc through the median sternotomy and left antero-lateral thoracotomy. The tumor was 85 X 210 X 140 mm in size and 1380 g in weight. The postoperative histological examination revealed the thymolipoma. We were able to find only 19 other reported cases of thymolipoma in Japanese literature. Of 19 cases, this thymolipoma is the largest one in proportion to the patient's body weight.

Child↗
PubMed1990

[A case of mediastinal cavernous hemangioma].

A 6-year-old boy had an abnormal shadow on the chest X-ray film. It showed a tumor shadow with calcification on the right hilum. The plain CT scan showed an anterior mediastinal mass and its density was similar to that of large vessels. On the angio CT scan the lesion displayed a much lower enhancement than large vessels. The tumor was resected completely by median sternotomy. It was 5.6 X 3.6 X 3.0 cm in size and contained a phlebolith 5 mm in diameter. The histological diagnosis was cavernous hemangioma.

Child↗