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Biomedical subjects

F Nakayama

Publications and source records attributed to F Nakayama.

At least 145 records · Page 8Linked to original sources
PubMed1981

Isolation and primary culture of adult human hepatocytes. Ultrastructural and functional studies.

Biopsy tissue of adult human liver was gently dissociated with collagenase followed by Dispase. By repeated low g centrifugation, a large number of almost pure, viable hepatocytes was obtained. This is the first report of a successful procedure for obtaining adult human hepatocytes for study in tissue culture. The isolated cells have the typical morphology of liver parenchyma, and these characteristics persist throughout the period of culturing. Evidence of their function is indicated by albumin synthesis. This procedure is now being used to study human hepatocyte functions in vitro and the effects of a variety of agents including carcinogens and viruses.

Adult↗
PubMed1981

Nonoperative measurement of pancreatic and common bile duct pressures with a microtransducer catheter and effects of duodenoscopic sphincterotomy.

Duodenoscopic manometry of the pancreatic duct (PD) and common bile duct (CBD) using a microtransducer catheter was distinct advantages over infusion manometry, giving absolute values of in situ intraluminal pressure. Microtransducer manometry was performed without medication in 49 patients with gallbladder stones (10), common bile duct stones (24), hepatic duct stones (6) and common bile duct dilatation (9), and was successful in 42 (86%) for PD and 36 (73%) for CBD. Ductal pressures showed respiration-synchronized biphasic variations superimposed by the arterial pulsation effect. Considerable postural change of the pressure values suggested that the recording posture should be predetermined. The PD-to-duodenum pressure gradient was higher than the CBD-to-duodenum gradient in most cases. Both were lower than those obtained previously by infusion methods. No significant differences were found in pressure profiles of the four disease groups. Endoscopic sphincterotomy significantly reduced not only CBD pressure but also PD pressure.

Adult↗
PubMed1981

Bacteria and gallstones. Etiological significance.

Two hundred consecutive gallstone cases have been subjected to bacteriological study employing improved anaerobic culture techniques. In addition to Clostridia species, species of anaerobes such as Bacteroides fragilis, Peptococcus, Veillonella, and Eubacterium are found to be present, some of which possessed beta-glucuronidase activity. This finding has a certain bearing on the etiology of bile pigment calcium stones. In addition to Escherichia coli, Bacteroides and Clostridium often found in the biliary tract may contribute to the formation of bile pigment calcium stones by producing beta-glucuronidase and thus deconjugating bilirubin diglucuronide to form free unconjugated bilirubin which in turn combines with calcium, leading to stone formation. In contrast, very low bacterial incidence was associated with cholesterol stones and so-called black stones--sometimes called pure pigment stones--and thus bacteria play little role, if any, in their formation. Therefore, bile pigment calcium stones and so-called black stones, which are often classified as pigment stones indiscriminately, should be differentiated not only because of their difference in their appearance and composition but also in their etiological background. Regardless of the kind of stones present in the common duct, the incidence of bacteria was found to be increased.

Bacteria↗
PubMed1981

Improved visualization of intrahepatic bile ducts by endoscopic retrograde balloon catheter cholangiography.

In seven patients with a patulous sphincter of Oddi, choledochoduodenal fistula, previous sphincterotomy, sphincteroplasty or bilioenteric anastomosis in which standard endoscopic retrograde cholangiography (ERC) with a #5 French catheter failed to visualize intrahepatic ducts sufficiently due to a backflow of contrast into the duodenum, ERC was attempted via a balloon catheter to prevent escape of contrast. The results were compared with those using a #7 French catheter. In contrast to the latter, which gave only insufficient filling of hepatic ducts, the former permitted full visualization in all cases. Consequently, intrahepatic stones were demonstrated in three patients, and bile duct changes consistent with carcinoma in another. The absence of hepatic lesions was confirmed in the remaining three patients. No adverse reactions were experienced. It is concluded that the use of a balloon catheter constitutes an effective aid in ERC for the diagnosis of hepatic lesions in selected cases where conventional ERC fails.

Adult↗
PubMed1980

Quantitative determination of bile acids in bile with reversed-phase high-performance liquid chromatography.

Separation and quantitation of glycine and taurine conjugates of commonly occurring bile acids in bile, i.e. lithocholic, deoxycholic, chenodeoxycholic, ursodeoxycholic and cholic acids in their naturally occurring states have been successfully accomplished using high-performance liquid chromatography. No preliminary purification of bile acids is required except ethanol extraction of bile. A muBondapak C18 column and acetonitrile--methanol--phosphate buffer and ultraviolet detector at 200 nm were used. Detection limit weas 0.05 microgram and linearity was observed in the range up to 16 microgram. Bile acid composition of ten randomly chosen normal human gallbladder bile samples is given. A large difference in bile acid composition between glycine and taurine conjugates was found to be present.

Bile Acids and Salts↗
PubMed1980

Oral cholelitholysis--cheno versus urso: Japanese experience.

The present status of the use of cholelitholytic agents in Japan is presented. Open and double-blind studies of chenodeoxycholic acid and ursodeoxycholic acid are compared with respect to their efficacy and safety. Although the in vitro solubilization of cholesterol with ursodeoxycholic acid seems to be less than with chenodeoxycholic acid, the higher dose of ursodeoxycholic acid which can be used because of the lack of side effects such as diarrhea and elevation of transaminases and a lower lithogenic index of bile obtainable favors ursodeoxycholic acid as an oral cholelitholytic agent at the moment.

Adult↗
PubMed1980

Utility of liver scintigraphy and angiography in preoperative detection of liver metastasis from gastrointestinal carcinoma.

One hundred and seventy cases of cancer of digestive tract were separated into three groups, advanced gastric cancer, biliary and/or pancreatic cancer and colorectal cancer. The presence of liver metastasis in each group was studied preoperatively by either liver scintigraphy or celiac and superior mesenteric angiography. In advanced gastric cancer and colorectal cancer, false negative ranged between 6.7-12.7 per cent by both scintigraphy and angiography. In biliary tract and/or pancreatic cancer, the ratio of false negative was significantly higher i.e. 18.8-22.6 per cent, which suggests the difficulty in diagnosing liver metastasis correctly in this group. The most frequent occurrences of false positive either in scintigraphy or angiography were those of masses of less than 2 cm in diameter. The difference in correct diagnosis ratio for liver metastasis between scintigraphy and angiography in all three groups was only 2.9 per cent. Hence, liver scintigraphy seems to be preferable for the purpose of detecting liver metastasis prior to surgery, since further angiographical examination entails irradiation, possible complications and economic factors.

Adult↗
PubMed1980

Hepatolithiasis in Japan: present status.

Intrahepatic gallstone or hepatolithiasis is one of the most difficult conditions encountered by surgeons in daily practice. A nationwide survey was conducted recently to document the state of hepatolithiasis in Japan and to establish proper methods of treatment. Over 160 institutions participated and 1,590 cases were collected. The stones were mostly of the bile pigment calcium stone variety and were found mainly in the left hepatic duct. The incidence was found to differ considerably from area to area. Pathologic features, diagnostic procedures and treatments currently available for hepatolithiasis are discussed.

Bile Ducts, Intrahepatic↗
PubMed1979

Class separation of bile lipids by thin-layer chromatography.

A thin-layer chromatography technique is described that permits separation of each class of bile lipid, such as cholesterol, free (unconjugated) bile acids, glycine- and taurine-conjugated bile acids and phospholipids, in a single run. The use of silica gel G-aluminium pre-coated sheets facilitates further processing, such as the extraction in situ of each class of separated bile lipids for determination by conventional methods.

Bile↗
PubMed1977

Gas-liquid chromatography and mass spectrometry of lanthionine, lysinoalanine, and S-carboxyethylcysteine.

A programmed-temperature gas-liquid chromatographic method of analysis of amino acids as their n-butyl esters of N(O)-trifluoroacetyl derivatives with a dual column system using OV-17 and Dexsil 300 GC as stationary phase is discussed. The method is particularly suitable for analysis of chemically modified amino acids in the hydrolyzates of chemically modified wool and other protein fibers. Combined gas-liquid chromatography-mass spectrometry is used to identify unequivocally the molecular structure of modified amino acids. Lanthionine, lysinoalanine, and S-(2-carboxyethyl)-cysteine in the hydrolyzates of chemically modified wool fibers can be quantitatively analyzed by the gas-liquid chromatographic method of Dexsil 300 GC. N(epsilon)-(2-Carboxyethyl) lysine was detected by the combined gas-liquid chromatography-mass spectrometry in the hydrolyzate of reduced wool treated with acrylonitrile.

Alanine↗
PubMed1976

Effect of intravenous fat emulsion on hepatic bile. Increased lithogenicity and crystal formation.

Hepatic bile from a series of patients with non-functioning gallbladders treated with an intravenous infusion of fat emulsion during prolonged preoperative fast was compared with that of controls. After the fat emulsion the bile was found to contain rhomboid tetragonal crystals whereas that of controls did not. It also contained polygonal crystals which showed Maltese crosses in polarized light. These crystals were also absent in the controls. Bile from cholecystectomized patients did not contain rhomboid cholesterol crystals after the infussion of fat but the occasional presence of polygonal crystals was noted. In both series of patients the infusion of fat resulted in increased lithogenicity of bile.

Bile↗
PubMed1975

Stratification of bile in gallbladder and gallstone formation.

The essential role of the gallbladder in gallstone formation should not be underestimated, as cholesterol stones originate in the gallbladder. The possible significance of stratification of bile in the gallbladder has been studied using recently proposed lithogenic parameters, such as triangular co-ordinates, lithogenic index and cholesterol saturation index. Bile becomes less lithogenic as the concentrating process in the gallbladder progresses. The concentrating activity of the gallbladder seems to differ considerably for each bile constituent. Bile salts are most concentrated in the gallbladder, followed by phospholipids and cholesterol. The presence of a selective absorption process in the gallbladder is suggested. As the gallbladder diminishes the lithogenicity of bile during storage, its role probably lies in its ability to interrupt the enterohepatic circulation leading to the production of lithogenic bile as well as providing a recess to ensure continuous growth of stones.

Bile↗