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Biomedical subjects

K Kawaguchi

Publications and source records attributed to K Kawaguchi.

At least 253 records · Page 14Linked to original sources

Basic techniques for DNA cloning and conditions required for streptomycetes as a host.

To develop a host-vector system in streptomycetes for DNA cloning, we examined the technical problems encountered and the conditions required for use of Streptomyces kasugaensis MB273 as the host. Basic techniques, such as plasmid DNA isolation, regeneration of mycelia from protoplasts and elimination of plasmids from cells were investigated. These techniques were found to be useful for many streptomycetes. Strain M518, a derivative of S. kasugaensis MB273, was found to have the following useful characteristics as a host. The plasmids of MB273 were easily cured by regeneration of mycelia from protoplasts. The protoplasts prepared from M518 regenerated mycelia at high frequency using an improved method and were efficiently transformed by plasmid DNA. The extra and intra cellular DNase activities were very weak, and no restriction endonuclease activity was detected. The sensitivity to various antibiotics was determined. This strain did not show any pathogenicity in mice nor suvival in the digestive organs of rats. MB273 and its derivatives died rather quickly in natural soil. M518 still forms aerial mycelial conidia. These results indicate that S. kasugaensis M518, derived from MB273, has useful characteristics as a host for DNA cloning. The techniques thus developed were found to be useful in other streptomycetes.

Animals↗

[Morphological and endocrinological study of theca cell tumor during pregnancy].

With a theca cell tumor of the ovary associated with pregnancy, an extremely rare occurrence in a 30 years old primigravida at 15 weeks of gestation, morphological and endocrinological studies were performed. The tumor was composed of cell-nests scattered among a fibromatous structure. The round or polygonal cells are rich in eosinophilic cytoplasm, resembling theca internal cells. The histochemical activity of 3 beta-HSD and G-6-PDH was demonstrated in these cells. They had the ultrastructures characteristic for steroid-producing cells, in some of which immature and mature Reinke crystalloid-like structures were identified. Mature ones were infrequently observed in contrast to the numerous immature ones. It is considered that a few cells might have differentiated into Leydig cells in the course of differentiation into thecomatous cells from ovarian stroma or mesenchyme. Judged from the rapid enlargement in early pregnancy, this tumor may depend on hCG. Serum estradiol was decreased immediately after removal of the tumor even at 15 weeks of gestation. Histochemical, ultrastructural and endocrinological findings suggest that the tumor was secreting mainly estradiol at the time of the operation.

3-Hydroxysteroid Dehydrogenases↗

[Clinical studies on children with congenital neurogenic bladder treated during the past 10 years].

During the past 10 years, 22 children (13 males and 9 females) had been treated for congenital neurogenic bladder at our department. These cases were reviewed for urinary tract infection, urodynamics, vesicoureteral reflux and renal deterioration. Urinary tract infections were observed during the follow-up period in 12 of the 22 cases (54.6%). The incidence was 38.5% in males and 88.9% in females. Cystometric findings were arbitrarily divided into 3 types; hyperreflexic type, areflexic hypertonic type and areflexic hypotonic type. Of the 17 cases examined, 3 cases were of the hyperreflexic type, 6 cases the areflexic hypertonic type and 8 cases the areflexic hypotonic type. Urinary tract infections were not observed in 5 of the 8 cases categorized as the areflexic hypotonic type compared to one of the 9 cases of the hyperreflexic and areflexic hypertonic types together. UPP was examined in 13 cases. UP max values were lower than normal in the areflexic type cases, but were normal or higher in the hyperreflexic type cases. Vesicoureteral reflux was examined in 9 cases. Reflux was observed in 9 ureters of 6 patients. Renal deterioration was observed in 6 cases; 4 cases of hydronephrosis and 2 cases of pyelonephritis. Management of 22 cases consisted of ileal conduit (1 case), clean intermittent self-catheterization (2 cases) and Cred é maneuver and/or pharmacologic treatments (19 cases). The usefulness of clean intermittent self-catheterization and management for vesicoureteral reflux were discussed centering on 4 selected cases.

Age Factors↗

Binding and endocytosis of cluster glycosides by rabbit hepatocytes. Evidence for a short-circuit pathway that does not lead to degradation.

Synthetic cluster glycosides containing either one, two, or three galactosyl or lactosyl residues per ligand were used to test the effect of carbohydrate clustering on binding by the rabbit hepatic Gal/GalNAc-binding lectin using either isolated rabbit hepatocytes or the solubilized, affinity-purified lectin. The tris- and bis-glycosides were superior to the mono-glycosides for inhibition of 125I-asialoorosomucoid binding to rabbit hepatocytes at 0 degrees C. The concentrations of the tris-glycosides required for 50% inhibition of 125I-asialoorosomucoid binding (4-8 microM) to hepatocytes were 50-100 times lower than the concentrations of the corresponding mono-glycosides required for 50% inhibition (400-500 microM). The isolated lectin, however, did not effectively discriminate between the mono-, bis-, and tris-glycosides, possibly indicating an organizational difference between the lectin in the cell membrane and the isolated lectin. When the cluster glycosides were labeled with 125I-tyrosine, it was shown that the tris- and bis-galactosides were bound to the hepatocytes at 37 degrees C, and that binding was followed by a step that led to ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid resistance, probably internalization. The process could be specifically inhibited by the neoglycoprotein Gal44-AI-bovine serum albumin, or by IgG specific for the hepatic lectin, but not by preimmune IgG. Internalization of the cluster glycosides did not lead to accumulation of ligand inside the cell, nor to degradation. Instead, the ligands were quickly released from the cells.

Animals↗

Differential diagnosis of liver parenchymal diseases by likelihood method using 12 laboratory data and age.

Liver parenchymal diseases were statistically diagnosed by likelihood method using 12 routine liver function tests and age. 444 cases of liver diseases were classified into 8 groups by histological diagnosis. A score diagnosis table was made from the data of these cases. For the likelihood diagnosis, data of each case were adapted to the score table and the probable diagnosis was calculated. Correct diagnosis rate of the first probable diagnosis was 50% in all cases and that of the first and the second was 71%. Descending order of the correct diagnosis rate of the first diagnosis was fatty liver (76%), liver cirrhosis (67%), slight histological changes (61%), acute hepatitis (51%), alcoholic liver injury (48%), chronic aggressive hepatitis 2A (43%), chronic persistent hepatitis (40%) and chronic aggressive hepatitis 2B (26%). In conclusion, differential diagnosis of liver parenchymal diseases was made easily with the score table of 13 informations with a considerable success.

Adult↗

Peritoneoscopic study on rat liver cell necrosis induced by carbon tetrachloride and allyl formate.

The surface changes of acute centrolobular and perilobular necrosis were studied in rat liver using peritoneoscopy. Centrolobular necrosis as induced by carbon tetrachloride and perilobular necrosis by allyl formate. Vessels observed on the control rat liver surface were identified as terminal hepatic veins by irrigation of the hepatic vein with a barium solution. Polygonal whitish markings were observed on the liver surface 48 hours after carbon tetrachloride administration. Terminal hepatic veins were regularly distributed throughout the central portions of the whitish areas. Reddish spots about 0.1 mm in diameter were scattered about the terminal hepatic veins. The reddish spots and whitish areas corresponded to the histological findings of central liver cell necrosis and infiltration by Kupffer and white blood cells. Six hours after allyl formate administration, round reddish spots about 0.3 mm in diameter were regularly distributed on the liver surface among the terminal hepatic veins. These spots corresponded to the histological findings of liver cell necrosis around the portal area. In summary, acute centrolobular and perilobular liver cell necrosis were newly observed as reddish spots by peritoneoscopy.

Animals↗

High-level induction of gamma interferon with various mitogens in mice pretreated with Propionibacterium acnes.

Various T-cell mitogens induced high levels of circulating gamma interferon (IFN-gamma) in mice that had been pretreated with Propionibacterium acnes. Administration of lipopolysaccharide, a B-cell mitogen, to these mice also caused pronounced production of IFN-gamma in addition to IFN-alpha and IFN-beta. The enhanced induction was most marked at about 1 week after the pretreatment.

Animals↗

Enhanced visualization of the portal vein system in superior mesenteric arterial portography using prostaglandin E1.

The portal vein system was clearly visualized in superior mesenteric arterial portography using prostaglandin E1. Angiographic examination was performed in 68 patients with various liver diseases during the 2 year period from 1980 to 1981. Twenty microgram of prostaglandin E1 was injected into the superior mesenteric artery 30 seconds before injection of 60 ml of contrast medium. The main portal vein was visualized in all of 68 cases. A high rate of success for visualization of the intrahepatic portal vein system by prostaglandin E1 was achieved. The first branches of the intrahepatic portal vein were visualized in 100% of the cases, the second branches in 82%, the third branches in 44%, and the fourth branches in 4% in the right portal vein system. In the left portal vein system, the first branches were visualized in 87%, the second branches in 41%, and the third branches in 3% of the cases. The intrahepatic portal vein system was more clearly visualized in females than in males (P less than 0.05). This procedure is simple, safe and useful for clear visualization of the portal vein system.

Alprostadil↗

Percutaneous transhepatic portal catheterization-modification of Chiba method and portal vein pressure in liver diseases.

Percutaneous transhepatic portal catheterization was performed in 68 cases of liver diseases in the 2 year period from 1978 to 1980. The Chiba University method was modified. Portal vein catheterization was successful in 61 cases (90%). Selective splenic vein catheterization was successful in 55 of the 61 cases (90%) and selective superior mesenteric vein catheterization in 59 cases (97%). The liver was punctured an average of 4.6 times in order to successfully insert the catheter into the main portal vein, and the number of punctures was less than 10 in 57 of the 61 cases (93%). The portal vein pressure was 310+/-67 mm H2O in idiopathic portal hypertension (8 cases), 290+/-83 in liver cirrhosis (33 cases), 193+/-71 in chronic hepatitis (7 cases) and 166+/-50 in fatty liver (4 cases). Portal vein pressure rose from 205+/-75 to 380+/-55 mm H2O in 11 cases after forced Valsalva maneuver. No major complications were encountered.

Catheterization↗

Differential uptake of D-galactosyl- and D-glucosyl-neoglycoproteins by isolated rat hepatocytes.

Bovine serum albumin was modified with 2-imino-2-methoxyethyl 1-thioglycopyranosides of galactose and glucose (Gal-AI-BSA, Glc-AI-BSA, respectively). Both types of neoglycoproteins were taken up by isolated rat hepatocytes. Gal-AI-BSA and Glc-AI-BSA inhibited the uptake of each other, and also inhibited the uptake of asialo-orosomucoid as expected from the results obtained with rabbit liver membranes (Stowell, C. P., and Lee, Y. C. (1978) J. Biol. Chem. 253, 6107-6110). Gal-neoglycoproteins of bovine serum albumin containing other linking groups between the galactose moiety and protein were found to be as effective in inhibition of the uptake of asialo-orosomucoid as Gal-AI-BSA, indicating that the method of carbohydrate attachment had little influence on endocytosis of galactose-terminated neoglycoproteins. In contrast, comparable Glc-neoglycoproteins (other than Glc-AI-BSA) were weak inhibitors. It thus appears that the positively charged amidino group present in Glc-AI-BSA contributes to the uptake of this neoglycoprotein by rat hepatocytes.

Animals↗

Kupffer cell hyperplasia in liver diseases. Demonstration by scanning electron microscopy of biopsy samples.

Kupffer cells were observed in liver biopsy tissues of 9 cases of liver diseases by scanning electron microscopy to prove Kupffer cell proliferation numerically. Kupffer cell count per 0.01 mm2 of cracked surface of liver lobule was 1.2 +/- 0.3 in the convalescent stage of a mild acute hepatitis case and 1.2 +/- 0.1 in a chronic persistent hepatitis case with slight inflammation. Whereas it was increased to 2.4-5.5 (P less than 0.01) in the convalescent stage of moderate to severe acute hepatitis cases, 1.8 +/- 0.1 (p less than 0.05) in a chronic active hepatitis case, 2.5 +/- 0.3 (p less than 0.001) in an alcoholic portal fibrosis case and 2.2 +/- 0.4 (p less than 0.001) in a liver cirrhosis case. Kupffer cell count per mm3 of liver lobule was estimated roughly 3,500 in the convalescent stage of a mild acute hepatitis case and in a mild chronic persistent hepatitis case and 7,000 to 16,000 in the convalescent stage of moderate to severe acute hepatitis cases.

Acute Disease↗

Scanning electron microscopy of rat degenerated hepatocytes after carbon tetrachloride intoxication.

Intracellular structures of hepatocytes were studied in rats intoxicated with carbon tetrachloride (CCL4) by scanning electron microscopy (SEM). Liver tissues were treated successively by conductive staining, critical point drying and fracturing with a scalpel. Fractured hepatocytes were mainly observed in the specimens 12 hours after CCL4 administration, Hepatocytes near the portal tract showed a normal dense cytoplasm. Swollen foamy hepatocytes were remarkable in the intermediate zone. They had numerous vesicles, 0.6-2.5 micrometer in diameter, which correspond to dilated cisternae of rough endoplasmic reticula (RER) observed by transmission electron microscopy. The vesicles were separated by a thin rim of the cytoplasm and communicated with each other through a round window. Besides vesicles, the foamy hepatocytes had some vacuoles 3-10 micrometer in diameter, which were extremely dilated RER. The vacuoles had many windows and communicated with the vesicles. Hepatocytes with dense cytoplasm and many vacuoles were distributed widely in the lobule. They were intermingled with the vesiculated hepatocytes inthe intermediate zone. Their vacuoles were 1.5-3.0 micrometer in diameter and some vacuoles communicated with each other. The vacuole had a well-developed wall with 0.1 micrometer diamter pores. The pores were sometimes arranged in line. Hepatocytes near the central vein showed necrotic changes. Most membraneous structures were disrupted except for fat droplets and the nucleus. The nucleoplasm was looser and nuclear pores disappeared. In summary, SEM demonstrated three-dimensionally organelle changes of hepatocytes induced by CCL4 administration.

Animals↗