Differential expression of S-adenosylmethionine synthetase isozymes in different cell types of rat liver

Mammalian S-adenosylmethionine (AdoMet) synthetase exists as two isozymes, liver-type and nonhepatic-type enzymes, which are the products of two different genes. It is known that the liver-type isozyme is only expressed in adult liver. Whereas, the nonhepatic-type isozyme is widely distributed in various tissues. In addition to the liver-type isozyme, a minor amount of the nonhepatic-type isozyme is also detected in adult liver. To investigate the distribution of these two isozymes in the liver in detail, the localization of these two isozymes was examined in each cell type of liver using a combination of cell fractionation technique and Western blot analysis. In the parenchymal cells, the liver-type isozyme protein was predominantly expressed, and a small amount of the nonhepatic-type isozyme protein was also detected. On the other hand, in the stellate cells the nonhepatic-type isozyme protein was exclusively or only expressed. Interestingly, a large amount of both isozymes were present in endothelial and Kupffer cell fraction. Using both antibodies to anti-rat nonhepatic-type and liver-type isozymes, respectively, immunohistochemical analysis clearly confirmed these results. In addition, in cultured hepatocellular carcinoma cells (FAA-HTC1), the nonhepatic-type isozyme protein only was detected, and the liver-type isozyme protein completely disappeared. This result indicates that the changes in the isozyme expression is regulated within the parenchymal cells. Administration of hepatotoxic drug carbon tetrachloride (CCl4) to rats resulted in about 40% to 50% reduction of enzyme activity in parenchymal cells and stellate cells compared with those of control rats. However, enzyme activity in endothelial and Kupffer cell fraction was not changed.

Phosphorylation of human general transcription factors TATA-binding protein and transcription factor IIB by DNA-dependent protein kinase--synergistic stimulation of RNA polymerase II basal transcription in vitro

DNA-dependent protein kinase (DNA-PK) has been known to catalyze phosphorylation of a number of regulatory factors involved in DNA replication and transcription such as simian virus 40 T antigen, p53, c-Myc, Sp1, and RNA polymerase II (Pol II). We examined the possibility that DNA-PK phosphorylates the general transcription factors TATA-binding protein (TBP) and transcription factor (TF) IIB, which play key roles in the formation of transcription initiation complex with Pol II. By using a highly purified preparation of DNA-PK from Raji cells, both TBP and TFIIB were shown to be phosphorylated in vitro by DNA-PK. We then investigated the effect of the phosphorylation of these factors on Pol II basal transcription. Stepwise analysis of preinitiation complex formation by electrophoretic mobility shift assay revealed that the phosphorylation of TBP and TFIIB by DNA-PK did not affect the formation of promoter (P)-TBP and P-TBP-TFIIB complexes but synergistically stimulated the formation of P-TBP-TFIIB-TFIIF-Pol II complex. Similarly, combination of the phosphorylated TBP and TFIIB synergistically stimulated Pol II basal transcription from adenovirus major late promoter. These observations suggest that DNA-PK could positively regulate the Pol II basal transcription by phosphorylating TBP and TFIIB.

Synchronous primary tumors of the extrahepatic bile duct and gallbladder

BACKGROUND AND OBJECTIVES

This study aims to clarify clinicopathologic characteristics of synchronous primaries of the extrahepatic bile duct and gallbladder. Understanding multiplicity and its histologic confirmation is an important step for successful surgical management.

METHODS

Of the 190 cases of resection of biliary tract neoplasms in this study, 10 had two separate tumors in the extrahepatic bile duct and gallbladder, which were investigated by the microscopic mapping technique for tumor extent using serial stepwise sectioning of specimens.

RESULTS

Clinical diagnosis was made successfully in only two cases. Detailed histologic examination revealed seven cases with synchronous primaries and three cases with metastatic tumors. Several microscopic parameters had additional diagnostic value. The presence of synchronous primaries is not necessarily associated with a poor prognosis, since we had four long-term survivors.

CONCLUSIONS

Diagnosis of synchronous extrahepatic biliary neoplasms is rarely made preoperatively. However, aggressive resection and careful microscopic examination are essential for the successful management and diagnosis of these special cases.

Patterns of lymphatic spread of carcinoma of the ampulla of Vater

BACKGROUND

The pattern of lymphatic spread of ampullary cancer is poorly documented. This pattern was clarified in order to define the rational extent of radical lymphadenectomy.

METHOD

Thirty-nine consecutive patients who underwent pancreaticoduodenectomy with radical lymphadenectomy were included in the study. A total of 1447 lymph nodes dissected from the resected specimens was examined to detect the presence of metastatic foci.

RESULTS

Twenty-one of the 39 patients had a total of 97 positive nodes. The sites of nodal involvement were the posterior pancreaticoduodenal (20 of 21 patients), inferior pancreaticoduodenal artery (IPDA; 12 of 21), anterior pancreaticoduodenal (three of 21), trunk of the superior mesenteric artery (three of 20), pericholedochal (three of 21), retroportal (two of 21), and para-aortic (three of five) regions. No metastases were found in the hepatic artery, cystic duct, perigastric, right coeliac, middle colic artery or right caval node groups.

CONCLUSION

Ampullary cancer mainly spreads to the posterior pancreaticoduodenal node group, then to the IPDA node group, and finally to the para-aortic area. The rational extent of radical lymphadenectomy should include the pancreaticoduodenal, superior mesenteric, pericholedochal, retroportal and para-aortic nodes.

Transthoraco-phrenic esophageal transection with paraesophago-gastric devascularization and splenectomy using a stapler

BACKGROUND/AIMS

Surgery remains the most reliable treatment for bleeding esophageal varices. The aim of this study was to introduce the operative technique of transthoraco-phrenic esophageal transection with paraesophagogastric devascularization using a stapler and to evaluate surgical results.

METHODS

Forty-five patients underwent the procedure; an elective procedure was performed in 22 patients (bleeders) and a prophylactic procedure in 23 patients (nonbleeders). Twenty-nine patients were classified as Child's A, 15 as B and 1 as C. Previous sclerotherapy had been performed in 5 patients.

RESULTS

No hospital deaths occurred. No patients developed postoperative anastomotic leakage, encephalopathy, or any complications related to phrenicotomy. Three patients bled postoperatively from recurrent esophageal varices. Cumulative 5-year bleeding rates were 5.0% in bleeders and 6.6% in non-bleeders. Two patients died due to bleeding varices. Cumulative 5-year survival rates were 72.1% and 78.8% in patients classified as Child's A and Child's B, respectively.

CONCLUSIONS

This procedure may be indicated for a majority of Child's A or B patients. Although the advantages of this procedure must be evaluated further, it may be an alternative when injection sclerotherapy and endoscopic ligation fail.

Intraluminal duodenal diverticulum with malposition of the ampulla of Vater

Intraluminal duodenal diverticulum is a rare congenital anomaly, sometimes associated with malposition of the ampulla of Vater. When the diverticulum is excised, the position of the ampulla should be determined carefully to avoid injury to pancreaticobiliary ducts. We report two patients with symptomatic intraluminal duodenal diverticulum and malposition of the ampulla. The ampulla was located on the rim of the diverticulum in one patient; in the others, the ampullary site was the posterior wall of the duodenum. Both patients underwent successful excision of the diverticulum without ductal injuries. As we have been unable to find any case with an ampullary location on the anterior wall of the duodenum, anterior duodenotomy followed by identification of the ampulla must precede excision of the diverticulum in order to avoid pancreaticobiliary ductal injuries.

Groove pancreatitis with recurrent duodenal obstruction. Report of a case successfully treated with pylorus-preserving pancreaticoduodenectomy

Groove pancreatitis is a rare subtype of chronic pancreatitis that is difficult to distinguish from pancreatic carcinoma. Most reported patients have undergone a Whipple procedure because pancreatic cancer was not ruled out. We report a case of groove pancreatitis in a patient who presented with recurrent duodenal obstruction without biliary stricture. The diagnosis of groove pancreatitis was based on characteristic episodes of repeated duodenal obstruction and the absence of radiographic evidence of cancer. Subsequently, our patient underwent a successful pylorus-preserving pancreaticoduodenectomy (PPPD). PPPD is a favorable alternative to the Whipple operation for duodenal obstruction resulting from this disease.

Pancreaticoduodenectomy for gallbladder cancer with peripancreatic nodal metastases

The prognosis of patients with advanced gallbladder carcinoma remains dismal. In the English language literature, we found only one 5-year survivor with peripancreatic lymph node metastases. We herein report a patient with marked peripancreatic nodal metastases, who has exhibited the longest survival (6 years) without recurrence after a pancreaticoduodenectomy combined with extended cholecystectomy. This outcome suggests that pancreaticoduodenectomy may be effective for clearance of peripancreatic nodal metastases from gallbladder cancer.

Right hepatectomy for pyogenic liver abscesses with true multiloculation

We report the case of 61-year-old woman with cryptogenic liver abscesses who had been profoundly ill with severe upper abdominal pain, impaired consciousness, prostration, continuous high fever secondary to sepsis, and thrombocytopenia (platelets, 1-5 x 10(4)/mm3) since admission. Ultrasonograms and computed tomograms revealed two separate multiloculated lesions in the right lobe of the liver, consistent with the liver abscesses. Immediately after diagnosis, percutaneous abscess drainage was performed under ultrasonographic guidance; however, only a small amount of pus was drained, prompting continuous irrigation of the abscess cavity. Four days later, transcatheter hepatic arterial infusion of antibiotics was attempted. However, the abscesses had enlarged and her general condition had worsened. On hospital day 8, she underwent right hepatectomy because the multiloculated lesions were refractory to drainage. The operation was successful in terms of hepatectomy, although she continued to suffer from sepsis, secondary right subphrenic abscess formation, and prolonged thrombocytopenia with associated coagulation disorders for two months. Examination of multiple cross sections of the resected specimen disclosed that the lesions consisted of aggregations of multiple small locules. There was no communication between the locules and there were true septations, rather than multiloculated lesions with pseudoseptations. The patient has been well for 2 years without recurrent abscess of the liver or any infectious disease.

Serial changes in contribution of substrates to energy expenditure after transthoracic esophagectomy for cancer

This study was designed to examine the metabolic response of patients following transthoracic esophagectomy for carcinoma of the esophagus during the administration of total parenteral nutrition. Thirty-five patients underwent a right thoracotomy and transthoracic esophagectomy with nodal dissection in the neck, mediastinum, and abdomen. The resting energy expenditure (REE) was measured preoperatively, and on the 1st, 3rd, 5th, and 7th postoperative days (PODs) using indirect calorimetry. The REE was significantly higher following transthoracic esophagectomy on PODs 1, 3, 5, and 7 than preoperatively. The caloric contribution of fat was significantly less on 3rd, 5th, and 7th PODs than on the 1st POD. In contrast, carbohydrate oxidation increased significantly on the 3rd, 5th, and 7th PODs compared to that of the 1st POD. These results may help optimize the nutritional support regimen for post-esophagectomy patients.

Omental delivery of prostaglandin E1 effectively increases portal venous blood flow in 66%-hepatectomized rats

Changes in portal venous blood flow (PVF) and systemic arterial blood pressure (SAP) were examined following prostaglandin E1 (PGE) application to the greater omentum and femoral vein in 66%-hepatectomized rats. PVF increased when PGE was administered to the omentum and femoral vein at 7.5 micrograms/kg per min for 2 min. The magnitude of PVF response due to both administrations was dose-dependent, but the duration of the PVF response in the omental application was longer than that in the femoral administration. SAP was unchanged after omental application, while femoral administration reduced SAP concomitant with an increase in PVF. These results suggest that, in this hepatectomized model, the omentum is a better site for PGE administration than the vein, and that omental PGE delivery is also effective for enhancing PVF without inducing any changes in SAP.

Preventive effect of 1-(2-tetrahydrofuryl)-5-fluorouracil in combination with uracil on colonic carcinogenesis induced by 1,2-dimethylhydrazine in rats

Thymidylate synthetase (TS) and thymidine kinase (TK) are key enzymes in de novo and salvage pathways for pyrimidine nucleotide synthesis, respectively. A high incidence of colorectal adenocarcinomas with varied grades of cell differentiation can be induced by 1,2-dimethylhydrazine (DMH) in rats. The marked increases of TS and TK activities were found in the poorly and well-differentiated adenocarcinomas of the colon, respectively. Oral administration of 1-(2-tetrahydrofuryl)-5-fluorouracil in combination with uracil (UFT) markedly reduced the number and accumulated area of colonic carcinomas, and TS activity in the poorly differentiated adenocarcinomas. A potential balance between the de novo and the salvage pathways for pyrimidine nucleotide synthesis was suggested to be related with the histopathological grades of cell differentiation. Suppression of colonic TS activity by UFT administration reduced the colonic carcinogenesis and the potency of the poorly differentiated adenocarcinomas of the colon.

Junction of the cystic duct with the left hepatic duct: report of a case discovered during laparoscopic cholecystectomy

We report a case of an anomalous junction of the cystic duct with the left hepatic duct found during laparoscopic cholecystectomy. Only five other patients with this anatomy have been reported. Two of these five patients had left-sided gallbladders, and the remaining patients (including ours) had their gallbladder in its normal location. Although the prevalence of this anomaly associated with left-sided gallbladders is 5.6 to 14.3%, this anomaly appears to be quite rare in patients with gallbladders in the normal position. In four cases, it was accompanied by left-sided gallbladder or low bifurcation of the common hepatic duct. This rare condition may accompany other biliary anomalies and should be kept in mind when performing cholecystectomy.

Distribution of phosphoneuroprotein 14 (PNP 14) in vertebrates: its levels as determined by enzyme immunoassay

We have established an enzyme immunoassay for phosphoneuroprotein 14 (PNP 14) which is mainly localized in the cytoplasmic matrix in presynaptic axon terminals and which is phosphorylated in vivo, as well as in vitro. Fab' prepared from rabbit IgG antibodies against bovine PNP 14 was conjugated with maleimide-horseradish peroxidase. The enzyme-conjugated Fab' was used as a second antibody in a sandwich enzyme immunoassay. This assay was able accurately to quantify 0.5-100 ng of rat PNP 14, as well as bovine PNP 14, and it was used for the determination of concentrations of PNP 14 in various rat tissues, neuroblastoma cells, and brains of other vertebrates. The concentrations of PNP 14 in the rat cerebrum, cerebellum, and testis were 1.1, 1.0, and 0.28 micrograms/mg of protein, respectively, and those in other tissues examined were less than 0.1 microgram/mg of protein. PNP 14 was also found in cultured cells, such as rat pheochromocytoma PC12 cells, NG108-15 cells, which are a hybrid between a mouse neuroblastoma and a rat glioma, mouse neuroblastoma Neuro-2a cells, and human neuroblastoma IMR32 cells. Furthermore, PNP 14-specific immunoreactivity was evaluated in the brains of various vertebrates, such as fish, frog, snake and chicken by immunoblot and enzyme immunoassay. The results revealed the immunoreactivity in the brains of all vertebrates examined and the levels were determined to be 0.6-2.1 micrograms bovine PNP 14 equivalents per mg of protein, suggesting that PNP 14 might be an essential component of the central nervous systems of vertebrates.

Indocyanine green disappearance enhanced by prostaglandin E1 in patients with hepatic resection

Indocyanine green (ICG) is a reliable indicator reflecting hepatocyte function and hepatic blood flow. Prostaglandin E1 (PGE) has been indicated to increase hepatic blood flow and protect the hepatocyte. The purpose of this study is to investigate whether PGE influences the ICG disappearance rate in patients with hepatic resection. Eleven patients with hepatic resection were divided into two groups according to the presence of liver cirrhosis (LC, n = 4) and chronic hepatitis (CH, n = 7). ICG 0.1 mg/kg was given as an intravenous bolus into the cubital vein 5 min after PGE administration, then the disappearance rate of ICG (ICG-K) was determined by a finger monitoring method. PGE administration increased ICG-K in the LC and CH groups with normal liver function, and the ICG-K response was dose dependent when the dosage of PGE ranged from 0.01 to 0.05 microg/kg/min. When ICG-K relative to the ICG-K of the control was defined as the ICG-K ratio, the daily course of the ratio in the LC group was higher than in the CH group. PGE increases the ICG-K of patients with normal liver function before and after hepatic resection, and this is evident in the case of liver cirrhosis.

Outcome of radical surgery for carcinoma of the gallbladder according to the TNM stage

BACKGROUND

The role of surgery in the treatment of gallbladder carcinoma (GBC) is controversial. The outcome after prospective radical surgery for GBC is discussed on the basis of the TNM stage of the tumor.

METHODS

One hundred six patients who had undergone radical surgery were selected. The standard radical procedure consisted of a cholecystectomy accompanied by lymph node dissection, wedge resection of the liver, and resection of the extrahepatic bile ducts. The stage was determined by pathologic examination of resected specimens.

RESULTS

Lymph node metastases were identified in no patients with T1 tumors (n = 15), 48% of patients with T2 tumors (n = 46), 72% of patients with T3 tumors (n = 25), and 80% of patients with T4 tumors (n = 20). One patient died within 30 days after radical surgery (mortality rate, 0.9%). There were 35 5-year survivors including 11 patients with nodal involvement, 10 with stage I tumors, 13 with stage II tumors, 10 with stage III tumors, and 2 with stage IV tumors. The cumulative 5-year survival rate in patients with stage I tumors was 91% (n = 15), 85% in patients with stage II tumors (n = 24), 40% in patients with stage III tumors (n = 28), and 19% in patients with stage IV tumors (n = 39). In patients with stage III and IV tumors the 5-year survival rate was 52% after curative resection (n = 35). This was significantly better than the 5% 5-year survival rate after a noncurative resection (n = 32).

CONCLUSIONS

The presence of lymph node metastases is strongly influenced by the depth of invasion of the primary tumor. Accurate determination of the TNM stage is essential in comparing surgical results, predicting patient outcome, and planning additional treatment. Standard radical surgery contributes to patient survival and is recommended in patients with advanced GBC.

Expression of S-adenosylmethionine synthetase isozyme genes in regenerating rat liver after partial hepatectomy

Mammalian S-adenosylmethionine (AdoMet) synthetase exists as two isozymes, liver-type and non-hepatic-type enzymes. To investigate the possible role of AdoMet synthetase in proliferating cells, we have examined the expression of these two isozyme genes in regenerating rat liver after partial hepatectomy using Northern blot analysis. In normal adult rat liver the non-hepatic-type isozyme mRNA was not detectable, however, when partial hepatectomy was performed, there was an obvious appearance of the non-hepatic-type enzyme mRNA after operation. The levels of non-hepatic-type isozyme mRNA was peaked at 4h and maintained the level at least till 8 h after operation, then decreased. In addition, the liver-type AdoMet synthetase gene expression was also induced by partial hepatectomy with similar time course. These results indicate that these two AdoMet synthetase isozymes may play an important role during the prereplicative phase which precedes DNA synthesis.

The extracellular matrices and vascularization of the developing corpus luteum in rats

The extracellular matrices and vascularization of the developing corpus luteum of adult female rats were studied with immunohistochemistry for laminin, type I, III and IV collagen and with electron microscopy. Ovaries were removed from Wistar-Imamichi rats that had a regular 4-day estrous cycle, 6 and 2 h before ovulation, immediately after ovulation, 6, 16 and 24 h after ovulation and at maturity of the corpus luteum and examined. The basement membrane of the follicles and capillaries of the theca interna started to break down around the entire circumference of the Graafian follicle 2 h before ovulation. More than 6 h after ovulation, dot-pattern positive reactions for type IV collagen and laminin were detected in the granulosa layer, and thin basement membrane structures appeared in association with the luteinizing granulosa cells. More than 16 h after ovulation, vascularization with the formation of capillary basement membrane was observed in the granulosa layer, and luteal mesenchymal cells with adjacent interstitial collagen components always appeared in close association with the newly formed capillaries. Our chronological observations revealed that both luteinizing cells and luteal mesenchymal cells are involved in the destruction and reconstruction of the follicular ECM, and that the luteal mesenchymal cells play an essential role in the neovascularization of the developing corpus luteum.

CPP32/Yama/apopain cleaves the catalytic component of DNA-dependent protein kinase in the holoenzyme

DNA-dependent protein kinase (DNA-PK) is composed of a 460-kDa catalytic component (p460) and a DNA-binding component Ku protein. Immunoblot analysis after treatment of Jurkat cells with anti-Fas antibody demonstrated the cleavage of p460 concomitantly with an increase in CPP32/Yama/apopain activity. Recombinant CPP32/Yama/apopain specifically cleaved p460 in the DNA-PK preparation that had been purified from Raji cells into 230- and 160-kDa polypeptides, the latter of which was detected in anti-Fas-treated Jurkat cells. The regulatory component Ku protein was not significantly affected by CPP32/Yama/apopain. DNA-PK activity was decreased with the disappearance of p460 in the incubation of DNA-PK with CPP32/Yama/apopain. These results suggest that the catalytic component of DNA-PK is one of the target proteins for CPP32/Yama/apopain in Fas-mediated apoptosis.

Reconstruction of two-dimensional current distribution from tangential MCG measurement

We describe a two-dimensional reconstruction method for tangential magnetocardiograms (MCGs). This method is based on two-dimensional Fourier analysis, and we used a new type of window function for tangential MCG to solve the problem of the small number of measurement points. By using this method, cardiac activity can be estimated as a two-dimensional current distribution. To determine the effectiveness of this method, we measured tangential MCGs of normal subjects, and compared the estimated current distribution with the actual cardiac muscle activity. Using this method, we were able to clearly show cardiac activity.

The mode of lymphatic spread in carcinoma of the bile duct

BACKGROUND

Knowing the prevalence of lymph node involvement associated with the location of the primary tumor is a prerequisite for operating with curative intent in carcinoma of the bile duct.

METHODS

We evaluated 80 patients with carcinoma of the bile duct or cystic duct to investigate the frequency of lymph node involvement, the mode of lymphatic spread, and prognosis, according to the location of the primary tumor.

RESULTS

The frequency of lymphatic spread of carcinomas in the proximal, middle, and distal bile ducts, excluding seven T1 tumors, was 48%, 67%, and 56%, respectively. With regard to the mode of lymphatic spread: (1) a metastatic pathway along the common hepatic artery predominated over that to the retropancreatic area in the proximal duct carcinoma group; (2) in the middle duct carcinoma group, metastatic lymph nodes were distributed widely, involving nodes around the superior mesenteric artery or at the para-aortic area; and (3) in the distal duct carcinoma group, metastatic nodes generally were localized around the head of the pancreas.

CONCLUSIONS

Understanding the mode of the lymphatic spread according to the primary tumor may be helpful for choosing the appropriate surgical approach with curative intent in bile duct carcinoma.