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N Kitamura

Publications and source records attributed to N Kitamura.

At least 343 records · Page 19Linked to original sources
PubMed1991

An alternatively processed mRNA generated from human hepatocyte growth factor gene.

We recently reported the isolation and sequencing of cDNA for human hepatocyte growth factor (hHGF) [Miyazawa, K., Tsubouchi, H., Naka, D., Takahashi, K., Okigaki, M., Arakaki, N., Nakayama, H., Hirono, S., Sakiyama, O., Takahashi, K., Gohda, E., Daikuhara, Y. & Kitamura, N. (1989) Biochem. Biophys. Res. Commun. 163, 967-973]. In the present study, we report the sequence of another cDNA clone for a shorter form of hHGF mRNA. Comparison of the sequence with that of the hHGF cDNA revealed that the two sequences are identical in their 5' ends up to 865 nucleotides downstream from the translation-initiation site, then completely diverge from each other. By Northern blot analysis, the hHGF-related 1.5-kb mRNA, which corresponded to the newly isolated cDNA variant, was identified in human placenta. Sequence analysis of a human genomic HGF clone showed that the diverged 3'-terminal portion of the mRNA is generated by alternative RNA-processing events utilizing a specific exon. The mRNA could encode a short hHGF molecule of 290 amino acids corresponding to the N-terminal portion of hHGF which consists of 728 amino acids. In order to examine the effect of the predicted translation product on hepatocyte growth, an expression plasmid for the cDNA variant was constructed and transfected into Cos cells. Immunoblotting analysis showed that the transfected Cos cells produced a protein of about 33 kDa. The protein product did not stimulate DNA synthesis by rat hepatocytes in primary culture.

Amino Acid Sequence↗
PubMed1991

Identification of the N-terminal residue of the heavy chain of both native and recombinant human hepatocyte growth factor.

The N-terminal amino acid of the heavy chain of native (purified from human plasma) and recombinant human hepatocyte growth factor (hHGF) was determined by analyses of amino acid composition and sequence of peptide fragments derived by enzymatic cleavage, peptide mapping, and fast atom bombardment mass spectrometry. Our results indicate that the N-terminal amino acid of the heavy chain of hHGF, both native and recombinant, is pyroglutamate, derived from glutamine at the 32nd residue from the initiation methionine.

Amino Acid Sequence↗
PubMed1991

Muscular architecture in the omasal laminae of cattle and sheep.

The muscular architecture of the bovine omasal laminae was examined. The omasal laminae had three thin smooth muscle layers which consisted of an intermediate layer and two lateral layers. The muscle bundles of the intermediate layers ran radially in the laminae and those of the two lateral layers ran parallel to the free border of the laminae. At the free border, three types of the muscular architecture were observed. In a histological study, the muscle bundles of the intermediate layer penetrated into the connective tissue around and smooth muscle fasciculi of the inner layer of the tunica muscularis of the omasal wall and attached to the bundles of both the inner layer and of the outer layer of the tunica muscularis. These results indicate that a re-evaluation of the muscular architecture in the omasal laminae is required to facilitate better understanding of the omasal morphology and physiology.

Animals↗
PubMed1991

Regional localization of the hepatocyte growth factor (HGF) gene to human chromosome 7 band q21.1.

Hepatocyte growth factor (HGF) is a polypeptide involved in liver regeneration. Its amino acid sequence and gene structure are similar to those of coagulation-related serine proteases. We have used a cDNA clone of HGF and flow-sorted human chromosomes to assign this gene to chromosome 7. Fluorescence in situ hybridization of the HGF genomic clones to human metaphase chromosome spreads showed the localization of this gene to 7q21. Estimation of fluorescent signals relative to arbitrary reference points (ARPs) allowed further localization to 7q21.1.

Cell Fractionation↗
PubMed1991

Cellular and subcellular localization of progastricsin in calf fundic mucosa: colocalization with pepsinogen and prochymosin.

The presence of gastricsin in bovine abomasal juice has been reported previously, but its exact site of origin has not yet been established. Specific polyclonal antibodies were used in the peroxidase-antiperoxidase method or the protein A/gold technique to label cells producing progastricsin. This immunocytolocalization was correlated with that of pepsinogen and prochymosin using specific polyclonal antibodies against those zymogens. The present study clearly established that progastricsin was located exclusively in chief, mucous neck, transitional mucous neck/chief, foveolar epithelial and surface epithelial cells of the calf fundic mucosa. Furthermore, progastricsin was found to be colocalized with pepsinogen and prochymosin in the same secretory granules of these cells. Progastricsin was not observed in parietal, gastric endocrine and undifferentiated neck cells.

Abomasum↗
PubMed1991

Native and recombinant human hepatocyte growth factors are highly potent promoters of DNA synthesis in both human and rat hepatocytes.

Human hepatocyte growth factor (hHGF) has recently been expressed as a recombinant polypeptide from Chinese hampster ovary cell transfectants. Using a primary rat hepatocyte bioassay, we have tested the biological activity of recombinant hHGF and compared it with native hHGF. Dose-response curves were almost identical, with half-maximal stimulation of DNA synthesis at 1-2 ng/ml (equivalent to approximately 10 pM). S-phase labeling index was similarly enhanced and numerous mitotic cells were observed. Recombinant and native hHGF also stimulated DNA synthesis and S-phase labeling index in primary adult human hepatocytes. Human cells were more responsive than rat hepatocytes, with recombinant hHGF slightly more potent than native hHGF (half-maximal stimulation 0.3 and 0.6 ng/ml, respectively). Since HGF levels rise in patients with fulminant hepatic failure and in animals after partial hepatectomy or administration of hepatotoxins, situations where liver regeneration occurs, HGF is suggested to play a key role in regulation of hepatic growth. The high potency of the factor on human hepatocytes reinforces its candidacy as a critical mitogen in human liver growth. The availability of a recombinant hHGF opens the way for in vivo experimental studies and to the possibility of using hHGF as a clinical therapeutic agent, either alone or in combination with other factors.

Adult↗
PubMed1991

Scanning electron microscopy of vascular architecture in the mucosa of sheep omasal laminae.

Three dimensional vascular architecture in the omasal laminae of sheep was studied by scanning electron microscopy of corrosion casts. The omasal laminae were equipped with well-developed subepithelial capillary network with various capillary loops and inter-papillar undulations. The capillary loops were more highly developed in the omasal papillae than in the inter-papillar space and more in the oral region than in the aboral. The capillary loops were inconspicuous in the inter-papillar space of the middle and aboral regions and in the omasal papillae of the aboral region. On the other hand, the inter-papillar undulation of the capillary network was more conspicuous in the aboral region than in the other regions of the omasal mucosa. These findings may indicate a regional diversity in the function of the omasal laminae.

Animals↗
PubMed1991

An ultrastructural study on the endocrine pancreas of Caiman latirostris, with special reference to pancreatic motilin cells.

Pancreatic endocrine cells of Caiman latirostris were investigated by electron microscopy using conventional and immunocytochemical methods. Ultrastructurally, four types of endocrine cells were classified according to the morphology of their secretory granules. Three types of endocrine cells were identified as either glucagon, insulin or somatostatin cells by the presence of such characteristic granules well established in mammals. The remaining endocrine cell type could not be classified by its ultrastructural features alone. Immunocytochemical observations confirmed the ultrastructural classification of glucagon, insulin and somatostatin cells. In addition, endocrine cells immunoreactive for either pancreatic polypeptide (PP) or motilin were identified. Morphometric analysis of PP- and motilin-immunoreactive granules demonstrated that they were the most polymorphous and smallest granules among the pancreatic endocrine cell granules. Although both PP and motilin granules closely resemble each other, motilin granules were smaller in size and more spherical in shape than PP granules.

Alligators and Crocodiles↗
PubMed1991

Motilin-immunoreactive cells in the duodenum, pyloric stomach and pancreas of caimans (Caiman latirostris and Caiman crocodilus, alligatorinae): a further comparison using region-specific motilin antisera.

Motilin-immunoreactive cells in the duodenum, pyloric stomach and pancreas of Caiman latirostris and Caiman crocodilus were investigated using region specific antisera for porcine and canine motilin molecules. Motilin-immunoreactive cells were found in the duodenum, pyloric stomach and pancreas of both caiman species. These cells were primarily open-type endocrine ones in the epithelium of the duodenum and pyloric stomach. Motilin-immunoreactive cells were observed in both the exocrine and endocrine portions of the pancreas, and frequently exhibited one or more cytoplasmic processes of variable length. Since motilin-immunoreactive cells do not cross-react with serotonin or any of the other pancreatic and gut hormones, they are considered to be cell type independent from any of the other known pancreatic or gut endocrine cells. The molecular similarity between caiman motilin and porcine and canine motilins and the heterogeneity of the motilin molecule in the caiman digestive system is discussed.

Alligators and Crocodiles↗
PubMed1991

[A case of "postoperative erythroderma" following coronary artery bypass grafting operation].

So-called "Postoperative Erythroderma" was experienced in a 68 year-old man who received CABG for unstable angina. After a seemingly uneventful recovery, he revealed high grade fever on 13th post operative day (POD), rashes over the whole body on 15th POD and pancytopenia on 20th POD. He died of sepsis, multiple organ failure and DIC on 21st POD. Blood transfusion (concentrated red cell: 3 units) was done on operation. In this case, the rate of premature and atypical lymphocytes increased, and the ratio of OKT4 (helper)/OKT8 (suppressor) decreased. These findings of the examination suggested that there was a possibility of cell-mediated immunological depression. We considered this to be acute GVHD after blood transfusion.

Aged↗
PubMed1991

[Hemopurification in the management of ARDS complicating multiple organ failure].

In the field of critical care medicine, it has been claimed that ARDS often develops as a part of multiple organ failure (MOF). Since multi-modality therapy is necessary in the management of MOF, it is also mandatory even in the management of ARDS. Among the various therapeutic approaches for patients with MOF, hemopurification is one of the most effective therapeutic tools. Various hemopurification methods such as hemodialysis, peritoneal dialysis, hemoadsorption, hemofiltration and plasma exchange have been applied in the management of MOR. However, our recent experiences suggest that continuous hemofiltration (CHF) and/or continuous hemodiafiltration (CHDF) are safest, most easily performed and effective hemopurification in the management of ARDS/MOF. The efficacy of hemopurification in the management of ARDS is summarized as follows. 1) Removal of humoral mediators and causative substances of ARDS following insults such as sepsis and trauma. 2) Treatment of pulmonary interstitial permeability edema which has been claimed to be one of the most important pathological conditions in ARDS. 3) Removal of excess water given as carrier in IVH solution and accumulating in the body. 4) Immunomodulation which has also been considered to be necessary in the treatment or prevention of ARDS.

Hemofiltration↗
PubMed1991

[A case report of a thrombosed mitral prosthesis diagnosed by 111In-oxine platelets scintigraphy].

The purpose of this report was to evaluate the efficacy of 111In-oxine labeled platelets scintigraphy for detection of thrombus in the prosthetic valve. A 50-year-old man underwent re-mitral valve replacement with a Björk-Shiley prosthesis because of malfunction of the xenograft in a previous operation. Almost one year later, this patient suffered from peripheral embolism and sight disturbance. There was no evidence of a thrombosed valve although it was suspected. Cineradiography showed the valve almost fully open, and there were no abnormal sounds when the valve closed. 111In-oxine labeled platelets scintigraphy was performed for the detection of thrombus in the mitral position. Hot areas of high quality in the scintigram were demonstrated in the mitral position. As a result, Björk-Shiley prosthesis was replaced with a Duromedics prosthesis. A small thrombus (10mm) surrounded by fresh tiny thrombi was found in a minor orifice of the Björk-Shiley prosthesis.

Heart Valve Prosthesis↗
PubMed1991

[Surgical repair of Scimitar syndrome with azygos connection by extracardiac conduit between right pulmonary vein and left atrium].

We present a surgical case of 41-year-old woman with Scimitar syndrome. Preoperative catheterization showed azygos connection and L-R shunt ratio of 45% without intracardiac malformations. To our knowledge, this combination has not been previously reported. At operation the right single pulmonary vein was found and drained into the inferior vena cava below the diaphragm. Because of counter clockwise rotation of the heart the distance of the scimitar vein and the left atrium was too long for direct anastomosis, a polytetrafluoroethylene tube (10 mm in diameter) was utilized for an extracardiac conduit using cardiopulmonary bypass. Postoperative course was uneventful. We conclude that this technique is effective for this syndrome with a large amount of L-R shunt and a sufficient patency is expected.

Adult↗
PubMed1991

[Significance of intraoperative measurement of secondary regurgitant tricuspid anulus].

We evaluated the dilated tricuspid anuli (10 cases) during operation by means of direct measurement of the lengths of each leaflet anulus and compared with control group whose anuli were normal (12 cases). The lengths of anterior leaflet anulus and posterior one were dilated significantly more than control group. In this study tricuspid regurgitation was mainly proved to be the dilated anterior leaflet anulus. But it was not identified whether the dilatation of posterior one was contributed to the tricuspid regurgitation with the correlation of cardiac output and right atrial pressure from the underlying data.

Dilatation, Pathologic↗
PubMed1991

[Left ventricular-right atrial shunt due to infective endocarditis--report of a case].

Acquired left ventricular-right atrial shunt is a very rare cardiac disease. Infective endocarditis, cardiac operative procedures, and thoracic trauma were reported as origins. We report a case of a patient with left ventricular-right atrial shunt due to infective endocarditis. A 53-year-old male who had aortic regurgitation due to infective endocarditis developed suddenly severe congestive heart failure. Two-dimensional and pulsed doppler echocardiography demonstrated left ventricular-right atrial shunt. Emergency operation was done. The fistula was found through the atrioventricular membranous septum. The position from the left view was just below the commissure between the right coronary cusp and non coronary cusp and the opening position from the right view was just above the septal leaflet of tricuspid valve. Aortic valve replacement and direct closure of fistula were done and patient's recovery was uneventful. Case reports of left ventricular-right atrial shunt due to infective endocarditis have been rarely seen, most of which were followed by poor prognosis. Surgical intervention in acute phase is recommended.

Endocarditis, Bacterial↗
PubMed1991

[Clinical experience of autotransfusion of shed mediastinal blood using a new chest drainage unit].

The autotransfusion system (ATS) of shed mediastinal blood is expected as one of the techniques for non-blood open heart surgery. The ATS which has been used previously for this purpose required such items as cardiotomy reservoir, vacuum bottle, infusion pump and was complicated to manipulate. This time we have used a new chest drainage unit, Sentinel Seal Autotransfusion System (Sherwood Medical Co.), and report our clinical experience. This unit consists of two component parts. One is a blood collection bag which is later used for reinfusion of shed blood. The other part is a regular chest drainage unit with the water seal which protects pleural cavity from atmosphere. We used this system for 24 cases of open heart surgery and studied about the hematological and biochemical changes after reinfusing the shed blood postoperatively. There were no complications and side effects related to the reinfusion. The unit we have used is simple to handle and is useful when returning shed blood. We believe that this unit is quite safe for clinical use and that it will become a new strong support for non-blood open heart surgery.

Blood Chemical Analysis↗