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K Tsukada

Publications and source records attributed to K Tsukada.

At least 19 recordsLinked to original sources
PubMed1998

A new pseudo-peptide analogue of the Arg-Gly-Asp (RGD) sequence inhibits liver metastasis of colon 26-L5 carcinoma cells.

We have investigated the effect of the pseudo-peptide analogue (FC-336) of the Arg-Gly-Asp (RGD) sequence in a liver metastasis model by the inoculation of a highly liver-metastatic cell line of colon 26 carcinoma (colon 26-L5) into the portal vein of BALB/c mice. The intraportal injection of colon 26-L5 cells with FC-336 resulted in a marked suppression of liver metastatic colonies in a dose-dependent manner and it reduced the liver weights to a normal level. However, the co-injection of tumor cells with a high dose of RGDS tetrapeptide led to a slight inhibition of liver metastasis. The multiple i.v. administration of FC-336 after tumor inoculation as well as the injection of FC-336 with tumor cells caused significant inhibition of experimental metastasis in the liver. The multiple i.v. administration of the RGDS peptide did not show any inhibitory activity. FC-336 significantly enhanced the survival rate of mice compared with untreated controls when injected intraportally with tumor cells or when intravenously administered after tumor inoculation. Zymography analysis showed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by colon 26-L5 cells, while RGDS peptide did not affect the enzymatic degradation. These findings clearly indicate that the pseudo-peptides of the RGD sequence (FC-336) have a potent inhibitory activity on liver metastasis of colon 26-L5 carcinoma cells.

Animals↗
PubMed1998

Quantitation of telomerase activity in hepatocellular carcinoma: a possible aid for a prediction of recurrent diseases in the remnant liver.

Because telomerase activity is necessary for cell immortality and probably associated with tumor progression, we have evaluated a possible aid for quantitation of the activity to predict intrahepatic recurrences after surgery in patients with hepatocellular carcinoma (HCC). HCC tissues obtained by surgical resection from 20 patients were studied. Telomerase activity was expressed as peaks with a periodicity through a fluorescence-based telomeric repeat amplification protocol using an autosequencer, and the quantity of activity was calculated from peak areas. A ratio of fluorescence intensity depending on telomerase to that of an internal standard was used as a value of relative telomerase activity (RTA). RTA in serially diluted S100 extracts from HepG2 cells was well correlated with the amount of the extracts. The mean RTA value of 36.4 +/- 27.8 (mean +/- SD, 3.21 to 105) in 9 patients suffering from early recurrences after surgery was significantly higher than that (9.84 +/- 7.65; mean +/- SD, 3.00 to 29.0) in 11 patients without intrahepatic recurrences during the early period (P = .004). These results indicate that RTA value can be a useful predictor for intrahepatic recurrences during the early period after surgical resection of HCC.

Adult↗
PubMed1998

A case of resection under the IVC-atrial venovenous bypass of a hepatoblastoma after intraarterial chemotherapy.

An 11-month-old infant with a huge hepatoblastoma occupying almost the entire liver was admitted to the hospital. Serum alpha fetoprotein (AFP) level was elevated to 685,120 ng/mL. Combination chemotherapy with continuous arterial infusion of tetrahydropyranyl Adriamycin (THP-Adriamycin) and cisplatin based on the 91B1 protocol of the Japanese Study Group For Pediatric Liver Tumor (JPLT) was administered as the adjuvant chemotherapy. The tumor responded to three courses of chemotherapy and shrank in size, although venocavography showed that the inferior vena cava (IVC) was completely occluded below the entry of the hepatic veins. Right hepatic trisegmentectomy was performed with an IVC-atrial venovenous bypass that prevented massive bleeding. In this case, it was recognized that the IVC-atrial venovenous bypass was advantageous in an infant. The procedure is very simple and the blood flow obtained by the bypass was sufficient. Two weeks postoperatively, three courses of chemotherapy were initiated after the protocol. The patient remains well without signs of recurrence 39 months postoperatively, and the AFP value has remained within 10 ng/mL.

Antibiotics, Antineoplastic↗
PubMed1998

Oral administration of a Kampo (Japanese herbal) medicine Juzen-taiho-to inhibits liver metastasis of colon 26-L5 carcinoma cells.

We have investigated the inhibitory effect of oral administration of Juzen-taiho-to, a Kampo Japanese herbal medicine, on liver metastasis by the inoculation of a liver-metastatic variant (L5) of murine colon 26 carcinoma cells into the portal vein. Oral administration of Juzen-taiho-to for 7 days before tumor inoculation resulted in dose-dependent inhibition of liver tumor colonies and significant enhancement of survival rate as compared with the untreated control, without side effects. We also found that liver metastasis of L5 cells was enhanced in BALB/c mice pretreated with anti-asialo GM1 serum or 2-chloroadenosine, and in BALB/c nu/nu mice, compared to normal mice. This indicates that NK cells, macrophages, and T-cells play important roles in the prevention of metastasis of tumor cells. Juzen-taiho-to significantly inhibited the experimental liver metastasis of colon 26-L5 cells in mice pretreated with anti-asialo GM1 serum and untreated normal mice, whereas it did not inhibit metastasis in 2-chloroadenosine-pretreated mice or T-cell-deficient nude mice. Oral administration of Juzen-taiho-to activated peritoneal exudate macrophages (PEM) to become cytostatic against the tumor cells. These results show that oral administration of Juzen-taiho-to inhibited liver metastasis of colon 26-L5 cells, possibly through a mechanism mediated by the activation of macrophages and/or T-cells in the host immune system. Thus, Juzen-taiho-to may be efficacious for the prevention of cancer metastasis.

2-Chloroadenosine↗
PubMed1997

Structure of the rat methionine adenosyltransferase 2A gene and its promoter.

In this study, to understand the regulation of methionine adenosyltransferase (MAT) gene expression, we isolated the rat MAT2A gene encoding MAT alpha2, the catalytic subunit of non-hepatic-type enzyme MAT II and characterized its structural organization and 5'-flanking region. The gene spans approximately 7 kbp and consists of nine exons interrupted by eight introns. The transcription initiation site, as demonstrated by primer extension analysis, is located 123 bp upstream of the translation start codon. Comparison of the structural organization of the rat MAT2A gene to that of the mouse MAT1A gene encoding MAT alpha1, the subunit of liver-type enzymes MAT I and III, shows that the exon structure of two genes is very similar and the insertion sites of all corresponding introns are identical. A canonical TATA box and a GC box, the potential Sp1-binding site, are found 32 bp and 70 bp upstream of the transcription initiation site, respectively. The 5'-flanking region also contains potential recognition sites for various transcription factors including AP-1, AP-2 and NF-IL6 (C/EBPbeta), and a large G+C-rich domain with the characteristics of a CpG island. The 5'-flanking sequence of the rat MAT2A gene has no significant similarity with those of the MAT1A genes. Transient transfection experiments using a luciferase reporter gene showed that the first 820-bp sequence of the 5'-flanking region directed high levels of luciferase activity in cultured rat kidney fibroblast (NRK-49F) and hepatocellular carcinoma (FAA-HTC1) cells, but not in primary rat hepatocytes. Deletion analysis suggested that the first 343 bp of the 5'-flanking region contained cell-type-specific promoter elements of this gene.

Animals↗
PubMed1997

Combined pancreaticoduodenectomy and hepatectomy for patients with locally advanced gallbladder carcinoma: long term results.

BACKGROUND: The objective of this study was to evaluate the efficacy of combined pancreaticoduodenectomy and hepatectomy for the treatment of patients with locally advanced gallbladder carcinoma. METHODS: Long term results over 5 years of follow-up were analyzed retrospectively in 17 consecutive patients with gallbladder carcinoma who underwent combined pancreaticoduodenectomy and hepatectomy with radical lymphadenectomy. The indications for pancreaticoduodenectomy were direct invasion of the adjacent organs (stomach, duodenum, or pancreas) and/or the presence of peripancreatic (head only) lymph node metastases. The hepatectomy performed was a nonanatomic resection of the gallbladder bed in 15 patients and an extended right hepatectomy in 2 patients. There was 1 in-hospital death (6%). RESULTS: Overall, 5 patients (29%) survived 5 years after surgery. Of these patients, four had Stage IVB disease with positive peripancreatic lymph nodes. Eight of the 10 patients who underwent a potentially curative resection survived longer than 3 years, whereas none of the 7 patients with residual tumor survived beyond 15 months. The 5-year survival of 50% (median survival: 58.5 months) in those undergoing a potentially curative resection was significantly better than the 5-year survival of 0% (median survival: 8 months) observed in those patients with residual tumor (P = 0.00086). CONCLUSIONS: Combined pancreaticoduodenectomy and hepatectomy is an efficacious treatment for patients with locally advanced gallbladder carcinoma, but only if a potentially curative resection is feasible. The presence of peripancreatic (head only) lymph node disease is not a contraindication for this procedure.

Adenocarcinoma↗
PubMed1997

Lymph node spread from carcinoma of the gallbladder.

BACKGROUND: Lymph node spread is the most common pattern of progression in gallbladder carcinoma (GBC) and is a prognostic factor. The purpose of this study was to determine the prevalence of lymph node metastases in patients with resected advanced GBC, and to evaluate the curative effects of radical surgery for patients with lymph node metastasis. METHODS: One hundred and eleven consecutive patients who had undergone radical surgery for GBC were included in this study. The pattern of lymph node metastases was examined histopathologically, using the TNM staging of the American Joint Committee on Cancer. RESULTS: There was no neurovascular invasion or lymph node involvement in 15 patients with pT1 tumors. Sixty of 96 patients with pT2-4 tumors had lymph node metastases. The pericholedochal lymph node was the most common metastatic lymph node, followed by the cystic lymph node. The frequency of metastases in retroportal, posterosuperior pancreaticoduodenal, and interaorticocaval lymph nodes was >15% in all cases. pT3-4 tumors had significantly more lymph node involvement (79%) and significantly higher N2:N1 ratios (2.5) than pT2 tumors (46% and 0.6, respectively). There was no difference in 5-year survival between N0 and N1 groups in pT2-4 tumors (66% in N0 and 53% in N1). Patients with N2 disease had a significantly worse prognosis, but 4 patients survived >5 years. CONCLUSIONS: The cystic and pericholedochal lymph nodes are the initial site of spread from GBC. The frequency of lymph node involvement is strongly influenced by the depth of invasion of the primary tumor. GBC limited to such lymph node metastases can be cured by surgery in >50% of such cases.

Adenocarcinoma↗
PubMed1997

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.

DNA-Activated Protein Kinase↗
PubMed1997

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.

Aged↗
PubMed1997

Validity and reliability of Structured Interview for Competency Incompetency Assessment Testing and Ranking Inventory.

The Structured Interview for Competency and Incompetency Assessment Testing and Ranking Inventory (SICIATRI) is a structured interview guide to assess the competency for giving informed consent to treatment among psychiatric and medical patients. The competency levels of 48 psychiatric and medical inpatients were assessed by SICIATRI. A relatively high- inter-rater reliability of the SICIATRI items (over half of the items had kappa > or = .60) and concurrent validity (sensitivity = .83, specificity = .67 as measured against the global judgement of competency rating by the attending physician) were obtained. In addition to its brevity (it takes about 20 minutes to complete), these findings may warrant application of this instrument in a clinical setting.

Adult↗
PubMed1997

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.

Ampulla of Vater↗
PubMed1997

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.

Animals↗
PubMed1997

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.

Drainage↗
PubMed1997

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.

Alprostadil↗
PubMed1997

Acute portal hypertension reflecting shear stress as a trigger of liver regeneration following partial hepatectomy.

The concept of injury in liver regeneration after partial hepatectomy (PHx), and the reason hepatocytes that have not been directly injured regenerate, remain unclear. It is known that shear stress resulting from blood flow plays an important role in the mechanism of remodeling blood vessels, and portal pressure reflects shear stress. This study was conducted to determine whether acute portal hypertension (APH) can become a trigger of liver regeneration as shear stress following PHx in a rat model. Portal pressures became elevated immediately after 70% and 90% PHx, peaking on postoperative day (POD) 3, and thereafter decreasing in proportion to the diminution of liver regeneration. The portal pressures after 90% PHx were significantly higher than those after 70% PHx even on POD 7, while those of the portocaval (PC) shunt groups decreased following PC shunting both with and without 70% PHx. The liver/body weight (LW/BW) ratio also decreased in the PC shunt both with and even without 70% PHx. The gradient expressions of class I antigen on sinusoidal endothelial cells (SEC) were found only in the periportal area, which has the highest portal pressure in the healthy rat liver. However, after hepatectomy these expressions were detected from the periportal area to the central venous area. These results suggest that APH as shear stress following PHx may not only become a trigger of hepatocyte regeneration, but also of SEC regeneration, and that surplus APH induces liver dysfunction.

Animals↗
PubMed1997

Lymph node recurrence of gallbladder carcinoma successfully managed by systemic chemotherapy with 5-fluorouracil and mitomycin C: report of a 5-year survivor.

Although gallbladder cancer (GBC) is believed to be chemoresistant, the effectiveness of chemotherapy against lymph node metastasis has been reported. We report a 70-year-old woman with advanced GBC in whom isolated, widespread lymph nodal recurrence after a radical resection responded completely to systemic chemotherapy with mitomycin C and 5-fluorouracil. This patient remains symptom-free with no evidence of disease at 6 years after surgery (5 years after the initiation of chemotherapy). Both our case and a literature review suggest that nodal disease appears more chemosensitive than the primary lesion in GBC. Chemotherapy may provide long-term palliation for selected patients with isolated nodal recurrence.

Aged↗
PubMed1997

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.

Adult↗