Akitoshi Koga

Surgical management and long-term follow-up of patients with choledochal cysts.

The medical records of 46 patients treated for choledochal cysts at Kyushu University from 1965 to 1990 were reviewed, and long-term follow-up results were evaluated based on the type of cyst and on the choice of surgical procedure. Of 46 patients, 41 (89%) were female and 5 (11%) were male, with a mean age of 24 years at the time of the initial operation. Seventy-eight percent of patients presented with an abdominal pain, 43% with jaundice, and 33% with an abdominal mass. Only seven patients (15%) presented with the classic triad. According to the Todani classification system, 26 patients (57%) had type I cysts, 2 (4%) had type II, and 18 (39%) had type IV. Four patients (9%) had biliary tract carcinoma. At the time of the initial operation, the major associated diseases were cholangitis in 15% and choledocholithiasis in 26% of cases. In 24 patients who had undergone previous cyst enterostomy, cholangitis developed in 88%, choledocholithiasis in 25%, and hepatolithiasis in 33% of patients, indicating a high complication rate after cyst enterostomy. Seventy percent of these patients needed reoperation. In contrast, cyst excision with Roux-en-Y hepaticojejunostomy gave excellent long-term results. Thus, cyst excision with hepaticojejunostomy is the definitive treatment of choice for type I and IV choledochal cysts.

Hepatolithiasis associated with cholangiocarcinoma. Possible etiologic significance

Three cases of primary bile duct carcinomas (cholangiocarcinomas) were found among 61 cases of hepatolithiasis. Cholangiocarcinoma arose from the extrahepatic bile duct in one and from the dilated intrahepatic bile duct in two patients. Hyperplasia of the columnar cells was often present. These hyperplastic epithelial cells often show papillomatous or adenomatous pattern, which are frequently associated with the presence of stones and the contaminated bile, and may show malignant changes leading to the development of cholangiocarcinoma.

Effect of chenodeoxycholic and ursodeoxycholic acids on isolated adult human hepatocytes

Chenodeoxycholic and ursodeoxycholic are effective cholelitholytic agents, but differ in their side effects. Chenodeoxycholic acid administration induces diarrhea and a transient rise of GOT, which are virtually nonexistent with ursodeoxycholic acid treatment. Lithocholic acid, a bacterial metabolite of chenodeoxycholic acid, has been implicated as a possible hepatotoxin. In the present investigation, the effect of chenodeoxycholic acid or ursodeoxycholic acid and their glycine and taurine conjugates on isolated human hypatocytes was directly assessed. Chenodeoxycholic acid had drastic effects on isolated human hepatocytes by reducing the number of microvilli and disrupting cell membranes. Pronounced release of GOT was observed. In contrast, ursodeoxycholic acid produced only slight morphological changes and enzyme release. Conjugation of each respective bile acids had a moderating effect.

Time-related morphological changes in cold-stored rat livers. A comparison of Euro-Collins solution with UW solution.

Rat livers were stored in cold UW solution and Euro-Collins solution for various periods. Morphological investigations were performed using light microscopy, as well as scanning and transmission electron microscopy. In the UW-stored livers, the appearance of blebs derived from hepatocytes and the destruction of sinusoidal endothelial cells (SEC) occurred more slowly than in the EC-stored livers. Almost no ultrastructural damage in the hepatocytes was observed even after 48 hr of storage in UW solution, while extremely swollen and degenerated hepatocytes were observed in the 48-hr EC-stored livers. After 48-hr of storage, livers stored in UW solution lost 7.9% of their weight though EC-stored livers gained 29.7% of weight. Light microscopic morphometry revealed that there was a significant increase of 24.3% in the mean hepatocyte area of 24-hr EC-stored livers, whereas the UW-stored hepatocytes did not show any significant increase even after 48 hr of storage. After perfusion fixation, livers stored for more than 8 hr in EC solution showed a mosaic pattern of uneven fixation indicating a microcirculatory disturbance, whereas the UW-stored livers showed a rather uniform fixation after 12 hr of storage. It is suggested that the microcirculatory disturbance occurred more slowly in the UW-stored livers than in the EC-stored livers, which might be due to the protection of SEC and the suppression of bleb formation and the swelling of hepatocytes by UW solution.

Morphogenesis of intrahepatic bile ducts of the human fetus

SummaryThe development of the intrahepatic bile ducts of the human fetus was investigated by light and electron microscopy. Bile canaliculi with microvilli and junctional complexes are already found in the embryo of 7 mm. Some of them are of the intracellular type. At six to seven weeks, large bile canaliculi bounded by four to seven liver cells appear. Subsequently, bile canaliculi are formed predominantly between three to four adjoining liver cells and this arrangement persists throughout later fetal life.The early intrahepatic bile ducts develop around the portal vein as epithelial cell plates derived from the hepatic duct and the branches sprout from the epithelial cell plates in several different places. The epithelial cell plates are separated from each other by primitive connective tissue and they change into a complex network of bile ducts. Formation of the intrahepatic bile ducts is completed by three months.Biliary duct cells at the end of the developing bile ducts are thought to transform into liver cells. Therefore, at the ducts of Hering various transitional cells appear between biliary duct cells and liver cells.The fine structure of the developing liver cells and biliaryduct cells is also described.

Fibronectin : a possible factor promoting cholesterol monohydrate crystallization in bile

To examine the hypothesis that fibronectin physiologically present in bile might be a possible nucleating factor, the concentrations of fibronectin in gallbladder bile were determined and its induced effect on nucleation time and on the form of vesicle were examined in bile-model and human gallbladder bile. The gallbladder bile samples taken from patients with cholesterol gallstone had a significantly higher concentration of fibronectin and the faster nucleation time than the control. However, no significant correlation was found between nucleation time and endogenous fibronectin concentration. The addition of 0.5, 1.2, 10 micrograms/ml of fibronectin into two kinds of bile-model significantly shortened the nucleation time in a dose-related manner. Nucleation time was significantly shortened by the addition of 1 microgram/ml exogenous fibronectin into abnormal bile while such an effect was absent in the control. The addition of fibronectin increased the size of vesicles observed by the electron microscope. The results suggest that fibronectin physiologically present in bile may be one of the possible nucleating factors.

Morphological and functional changes in the tight junctions of the bile canaliculi induced by bile duct ligation.

SummaryThin sections after bile duct ligation showed that the depth of tight junctions appeared to increase and that the distance between individual punctate contacts appeared to become irregular and wider than in controls. The freeze fracture replicas clearly demonstrated these changes in the tight junction morphology. Changes were noted most conspicuously in the tight junction three weeks after ligation. Measurements of the junctional morphology in control and ligated specimens showed that the junctional depth had increased two fold in the latter, whereas the number of strands had scarcely changed. Lanthanum tracer experiments showed that the tight junctions did not permit the passage of the tracer in normal nor ligated rats. It was concluded that the mechanism of obstructive jaundice could not be related to changes in junctional morphology causing increased junctional permeability.

Electron microscopic observations on the mucous secretory activity of the human gallbladder epithelium

SummaryMucous secretory activity of the human gallbladder epithelium was investigated by light and electron microscopy and with histochemical techniques.There are two types of granules in the supranuclear region of the epithelial cells. The one low in density contains a fine filamentous material and gives a strongly positive silver methenamine reaction. The other is dense and only faintly positive. The granules of the former are considered to be mucous secretory granules and the granules of the latter may be lysosomes. PAS positive granules correspond presumably to both types of granules mentioned above.The mucous secretory granules are considered to be synthesized by the Golgi apparatus and the granular endoplasmic reticulum as has been confirmed in other mucous secretory cells. Their content is released from the cell by reverse pinocytosis.Typical goblet cells occur frequently in the fetal epithelium, but cannot be observed in the adult specimens.

Isolation and primary culture of adult human hepatocytes

SummaryBiopsy 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.

Ultrastructural changes in rat liver sinusoids during storage in cold Euro-Collins solution

SummaryChanges in the sinusoids of rat livers stored in cold (2° C) Euro-Collins solution for various periods were observed using combined scanning (SEM) and transmission electron microscopy (TEM). The sinusoidal endothelial cells were vulnerable to cold ischemia. Fenestrations of the endothelial cells were enlarged and became mesh-like after a 4-h preservation period. Following 8 h storage the sieve plates and cytoplasmic processes of the endothelial cells were destroyed and there was a tendency for the perikaryon to desquamate. Blebs derived from hepatocytes were seen after 4 h and these increased in number and size with prolonged preservation. Although the sinusoids were filled with blebs after 24 h preservation, no irreversible ultrastructural damage in the parenchymal cells was observed. Within 12 h storage, the liver had a mosaic pattern after perfusion fixation indicating uneven fixation and profound circulatory disturbance. These results suggest that endothelial cell destruction and/or numerous blebs may have unfavorable effects on the microcirculation of the transplanted liver after prolonged preservation.