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Shinji Tanaka

Publications and source records attributed to Shinji Tanaka.

162 records · Page 9Linked to original sources
PubMed2002

Minimally invasive hepatectomy: modulation of systemic reactions to operation or laparoscopic approach?

BACKGROUND: A new concept of surgical stress has been proposed that consists of both aggressiveness of operation and systemic reactions to an operation. METHODS AND RESULTS: We have investigated a possible modulation of such systemic reactions to operation and have demonstrated the following 3 points: (1) coagulation and fibrinolytic systems are independently activated during hepatectomy and such activation can be modulated by protease inhibitors such as nafamostat mesilate and antithrombin III; (2) elevated thromboxane A2 during hepatectomy is characterized in the prostanoid system, the elevation of thromboxane A2 is inhibited by thromboxane A2 synthetase inhibitor, and postoperative liver injury is reduced; (3) cytokine response induced by hepatectomy is modulated by preoperative administration of methylprednisolone, leading to possible prevention of bacterial translocation. Therefore, modulating systemic reactions to hepatectomy may be important for successful minimally invasive hepatectomy. Another important option for minimally invasive hepatectomy is the use of operative procedures such as laparoscope or thoracoscope. We have investigated the usefulness of a laparoscopic hepatectomy from the standpoints of early and long-term outcome after hepatectomy. Laparoscopic hepatectomy, which is a difficult and dangerous procedure, can be a feasible option and can result in better short-term outcome and a similar long-term outcome after hepatectomy when compared with conventional open hepatectomy. Therefore, the laparoscopic approach is also a viable option for minimally invasive hepatectomy. CONCLUSIONS: Modulation of systemic reactions to the operation itself and laparoscopic hepatectomy may be new strategies for performing minimally invasive hepatectomy.

Blood Coagulation↗
PubMed2002

Serological comparison of serum pepsinogen and anti-parietal cell antibody levels between Japanese and German patients.

BACKGROUND: Atrophic gastritis is more common in Japan than in Germany. The expression of anti-parietal cell antibody has been implicated in the genesis of atrophic gastritis associated with Helicobacter pylori infection. OBJECTIVE: We investigated the difference in serum levels of pepsinogens and in anti-parietal cell antibody expression between Japanese and German patients. METHODS: We recruited 102 Japanese and 46 German patients with dyspepsia. Endoscopic examination detected no localized lesions in the upper gastrointestinal tract of any patients. Anti-parietal cell antibody was investigated by enzyme-linked immunosorbent assay with the purified porcine H+,K+-ATPase fraction and immunohistochemistry. H. pylori infection was diagnosed by the presence of anti-H. pylori antibody, by using the urease test and by histological examination. Serum levels of pepsinogen I and II and of gastrin were measured by a modified radioimmunoassay. RESULTS: Seventy-one Japanese (70%) and 17 Germans (37%) were positive for H. pylori. Serum levels of anti-parietal cell antibody were not significantly different between Japanese and Germans in both H. pylori negative and positive groups. The serum pepsinogen I/II ratio and gastrin levels were altered by H. pylori infection in both populations. Moreover, anti-parietal cell antibody levels were higher in H. pylori-positive patients with low pepsinogen levels than in those with high pepsinogen levels in both populations. CONCLUSIONS: The levels of anti-parietal cell antibody do not differ statistically between Japanese and Germans. Anti-parietal cell antibody might play a role in the progression of atrophic gastritis in both Japanese and German patients.

Adolescent↗
PubMed2002

Clinical significance of vascular endothelial growth factor C expression and angiogenesis at the deepest invasive site of advanced colorectal carcinoma.

AIM: Vascular endothelial growth factor C (VEGF-C) is known to be associated with the development of the lymphatic vascular system. The aim of this study was to elucidate the clinical significance of VEGF-C expression and microvessel density (MVD) at the deepest invasive site in advanced colorectal carcinoma (CRC). METHODS: 152 patients who had undergone surgical resection for advanced CRC entered this study. VEGF-C expression was examined immunohistochemically with anti-VEGF-C polyclonal antibody C-20. Tumor MVD was determined immunohistochemically with anti-CD34 antibody. VEGF-C expression was defined as positive if distinct staining of the cytoplasm was observed in at least 10% of tumor cells at the deepest invasive site, central portion and superficial part of the tumor. MVD was estimated by averaging the count of three x400 fields in the most vascular area at the deepest invasive site. RESULTS: VEGF-C expression was detected in 71 of 152 lesions (46.7%) at the deepest invasive site. VEGF-C expression correlated significantly with poorer histologic grade, depth of invasion, lymphatic invasion, lymph node metastasis, venous invasion, liver metastasis and Duke's stage. At the central portion and superficial part, there were no significant differences between VEGF-C expression and clinicopathological findings. VEGF-C expression at the deepest invasive site also correlated significantly with MVD. In cases with curative surgery, patients with VEGF-C expression at the deepest invasive site had a significantly poorer prognosis than those without VEGF-C expression. Furthermore, prognosis for patients with both VEGF-C expression and high MVD at the deepest invasive site was significantly poorer than that of patients without VEGF-C expression and with low MVD. Multivariate analysis with logistic regression for 5-year survival in patients with curative surgery showed that lymph node metastasis and VEGF-C expression were significant risk factors. CONCLUSION: VEGF-C expression at the deepest site of tumor invasion can be a useful predictor of poor prognosis in advanced CRC and show a close relation to angiogenesis.

Aged↗
PubMed2002

[Current therapeutic strategy of hepatocellular carcinoma with extensive portal thrombus].

Prognosis of the patients with hepatocellular carcinoma with tumor thrombi in the portal vein is known to be extremely poor. The current results of various therapies, such as surgery, chemotherapy, immuno-therapy, radiation and combination therapy were reviewed, herein. Our recent therapeutic strategy for hepatocellular carcinoma with tumor thrombi in portal vein is also shown.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Adhesion behavior of peritoneal cells on the surface of self-assembled triblock copolymer hydrogels.

Adhesion behavior of cells to the surface of physical hydrogel membranes prepared by water-induced self-organization of precisely synthesized ABA-triblock copolymers comprised of poly(beta-benzyl L-aspartate) (PBLA) as A segment and poly(ethylene oxide) (PEO, molecular weight = 20 000) as the B segment were investigated. The cast film from the methylenechloride solution of these copolymers swelled in water very rapidly forming hydrogels (100-400% water content of total weight). The content of PBLA affected the strength, the hydrophobicity, and the amount of water involved in the hydrogel surface. During the early stage of cultivation with murine peritoneal cells, cell adhesion on the hydrogels of PEO and PBLA with 18 (20K18) and 25 (20K25) monomeric units was not observed, while adhesion on the hydrogels of PEO and PBLA with 32 (20K32) and 55 (20K55) monomeric units was successful, suggesting more than 12 mol % in PBLA content is necessary for adhesion of these cells. Although cell spreading on the hydrogels of 20K18, 20K25, and 20K32 was not sufficient, the hydrogel of 20K55 allowed cell adhesion and spreading to be bipolar with leading edge whose raffling is active with pseudopodium and lamellipodium as well as PBLA homopolymer, suggesting active motility of these cells. Remarkably, prolonged incubation restored adhesiveness onto the films at 20K18 in contrast to adhesion with 20K25 despite low hydrophobicity. It is conceivable that adaptation of proteins and chemical changes to the surface during the culture period may participate in these phenomena. Mechanical properties and interaction between cell and these copolymer hydrogels could be controlled by composition of block segments, and optimization for implants could also be attainable.

Adhesiveness↗
PubMedDate not supplied

Clinicopathologic features and endoscopic resection of early primary nonampullary duodenal carcinoma.

Early primary nonampullary duodenal carcinoma is an extremely rare disease with poorly defined clinicopathologic features; early detection of this carcinoma is not common. To clarify the clinicopathologic characteristics of early primary nonampullary duodenal carcinoma and retrospectively analyze methods of treatment. Seventeen early duodenal carcinomas identified between 1994 and 2001 in 15 patients were studied. Lesions were divided into 2 groups: sporadic carcinoma (10 cases in 10 patients) and familial adenomatous polyposis associated carcinoma (7 cases in 5 patients). Clinicopathologic features and methods of treatment were compared between groups. The mean age of patients with sporadic carcinoma (63.8 years) was significantly higher than that of patients with FAP-associated carcinoma (34.9 years). The incidence of sporadic carcinoma was significantly higher in men that in women (M:F ratio 9:1); the difference between sexes in the incidence of FAP-associated carcinoma (1:4) was not significant. There was no significant difference between both groups in relation to tumor size, location, gross appearance, or histopathology. Thirteen of the duodenal tumors were treated by endoscopic mucosal resection (EMR), two by polypectomy, and two by open surgery. Complications were encountered in 1 of 15 cases (6%); local bleeding occurred after one EMR, but hemostasis was achieved endoscopically. The mean follow-up period for all patients was 51.7 months. No patients experienced recurrence after resection. The significant differences between patients with sporadic and those with early FAP-associated duodenal carcinoma were in age and sex. Endoscopic resection appears to be a safe and efficient treatment of carefully selected patients with early primary nonampullary duodenal carcinoma.

Adenomatous Polyposis Coli↗
PubMedDate not supplied

Angiogenesis in advanced colorectal adenocarcinoma with special reference to tumoral invasion.

BACKGROUND: Angiogenesis is a crucial step in tumor growth and progression. Its quantification by microvessel counting has a prognostic value in several types of malignancies and recently has been appraised in gastrointestinal tumors. AIM: To assess the prognostic significance of microvessel quantification in colorectal carcinomas, studying its association with hematogenous metastases, survival and clinicopathological variables such as size, histologic differentiation and depth of tumoral invasion. PATIENTS/METHODS: Forty eight patients with colorectal adenocarcinoma were included in this study. Histologic sections of invasion tumoral margin (4 microns) were analyzed and endothelined microvessels were immunostained with monoclonal mouse Von Willebrand Factor (anti-FVIII). The microvessel count was performed from the identification of the area with increased microvessel density--hot spots--and results of the mean in five of these fields. RESULTS: The cut-off microvessel count was 14 microvessels/0.785 mm2, which divided the sample into hypovascular and hypervascular groups. While 2/8 (25%) tumors with muscularis propria invasion were classified as hypervascular, 11/15 (73%) tumors with serosa or perivisceral fat were classified as hypervascular. However, a non-significant statistical association was found between the angiogenesis quantification, hematogenous metastases, survival and clinicopathological variables such as size and histologic differentiation of the tumor. CONCLUSIONS: The findings of significantly increase of microvessel count in conformity with tumoral invasion depth supports the hypothesis that tumor progression might be related to angiogenesis. Although angiogenesis is an important step in the tumoral growth and during the metastatization process, other factors can be implicated.

Adenocarcinoma↗
PubMedDate not supplied

Clinical significance of angiogenesis in rectal carcinoid tumors.

This study was designed to examine angiogenesis in rectal carcinoid tumors in relation to the clinicopathologic features. Seventy-seven rectal carcinoid tumors were studied clinicopathologically and experimentally. Cellular proliferation and microvessel density (MVD) were examined immunohistochemically. We used the antibodies MIB-1 for Ki-67, DO7 for p53, and NU-4A1 for CD34 expression in this study. Ki-67 labeling index (LI) of all lesions was below 3%, and the median Ki-67 LI of all lesions was 0.68+/-0.70% (mean +/- SD). A correlation was recognized between tumor size, metastasis and Ki-67 LI (p<0.05). Median MVD of all lesions was 25.9+/-13.1 (mean +/- SD). MVD was correlated with the tumor size (p<0.01), presence of depression (p<0.01), lymphatic (p<0.01) or venous (p<0.05) invasion, and existence of metastasis (p<0.01). But there was no significant relationship between MVD and Ki-67 LI. p53 protein was detected sporadically in only 1 case (1.3%) demonstrating both liver and lymph node metastases. Rectal carcinoid tumors are slow-growing tumors with a lower proliferative activity. Angiogenesis plays an important role in progression of rectal carcinoid tumors independent of the cellular proliferative activity.

Antigens, CD34↗
PubMedDate not supplied

Determining depth of invasion by VN pit pattern analysis in submucosal colorectal carcinoma.

The aim of this study was to clarify whether the pit pattern on the surface of submucosal colorectal carcinoma is associated with level of invasion. We examined the VN pit-pattern (loss or decrease of pits with an amorphous structure) area of the tumor surface in 18 submucosal carcinomas that were classified based on gross appearance as either superficial or broad based sessile polypoid tumors. Pit pattern determination was made according to a previously reported system. We then evaluated the relation between the VN pit-pattern area, the maximum diameter of the VN pit-pattern area obtained stereoscopically after resection, and the depth of submucosal invasion. There was a significant correlation between the area and maximum diameter of the VN pit-pattern segment. There was also significant correlation between the maximum diameter of the VN pit-pattern area and the depth of submucosal invasion. Lesions with a maximum VN pit-pattern area diameter <5 mm showed a depth of submucosal invasion of <1500 microm. In submucosal colorectal carcinoma of the superficial or broad based sessile polypoid type in gross appearance, measurement of the maximum VN pit-pattern area diameter allows estimation of the depth of submucosal invasion.

Carcinoma↗
PubMedDate not supplied

The role of MTA1 gene expression in human hepatocellular carcinoma.

The MTA1 gene has been identified as metastasis-associated gene and has been seen to correlate with the degree of invasion and lymphatic metastasis in gastric, colorectal, and esophageal carcinomas. We investigated the possible role of MTA1 gene expression in hepatocellular carcinoma (HCC). The mRNA expression level of the MTA1 gene was examined using reverse transcription polymerase chain reaction (RT-PCR) in HCC and paired non-tumor liver tissues which were obtained from 33 patients who underwent curative hepatectomy. The expression level of each case was calculated as tumor/non-tumor (T/N) ratios. To clarify the clinical significance of MTA1 gene expression in HCC, patient disease-free survival rate after hepatectomy were univariately analyzed using 25 clinicopathological variables, including MTA1 expression level. High expression (T/N > or =1) of the MTA1 gene in HCC as compared to the paired non-tumor tissues was recognized in 14 of 33 (42%) samples. With regard to the differentiation of HCC, the high expression of MTA1 gene in well or moderately differentiated HCC and poorly differentiated HCC were observed in 9 of 27 (33%) and 5 of 6 (83%) samples, respectively. There was no relation between expression levels of the MTA1 gene and cancer invasion to the portal vein or intrahepatic metastasis. However, the disease-free survival rate of the MTA1-high expression group (T/N > or =1) was significantly lower than that of the MTA1-low expression group (T/N <1) (p<0.05). High expression of the MTA1 gene is suggested to be a new prognostic indicator after curative hepatectomy for HCC.

Aged↗
PubMedDate not supplied

Hypoxia-inducible factor-1alpha expression and angiogenesis in gastrointestinal stromal tumor of the stomach.

Hypoxia inducible factor (HIF)-1 is reported to transactivate expression of vascular endothelial growth factor (VEGF), which is an important angiogenic factor. The aim of this study was to elucidate the clinical significance of HIF-1alpha expression in gastrointestinal stromal tumors (GIST). Specimens obtained from 53 patients who underwent surgical resection for GIST of the stomach were used in this study. Specimens were examined immunohistochemically for HIF-1alpha, VEGF, and Ki-67 expression. Tumor microvessel density (MVD) was determined immunohistochemically with anti-CD31 antibody and was estimated by averaging the counts from three high-power fields in the area showing the greatest neovascularization. HIF-1alpha expression was detected in 17 (32.1%) of 53 lesions and was correlated significantly with tumor size, liver metastasis, VEGF expression, and MVD. Prognosis was significantly poorer in patients with tumors expressing HIF-1alpha than in patients with tumors lacking HIF-1alpha expression. HIF-1alpha may play a role in angiogenesis and tumor progression of GIST through regulation of VEGF.

Adult↗
PubMedDate not supplied

Frequent loss of heterozygosity on chromosome 10p15, a putative telomerase repressor/senescence gene locus, in gastric cancer.

Previous studies suggest that a telomerase repressor/senescence gene, which acts as a tumor suppressor gene, may be located on chromosome 10p15. However, there are no studies on alterations on chromosome 10p15 in gastric cancers. We, therefore, examined loss of heterozygosity (LOH) on the 10p15 in gastric cancers by microsatellite assay. Two microsatellite loci, D10S501 and D10S602, were used. Fifty-seven gastric cancers, including 36 intestinal type and 21 diffuse type, were selected. LOH at D10S602 and D10S501 was detected in 6 of 18 (33%) and 5 of 27 (19%) gastric cancers, respectively. There was no significant correlation between LOH at these loci and clinicopathologic features, including patient age, sex, tumor location, histologic subtype, depth of invasion, and lymph node metastasis. These data suggest that a putative telomerase repressor/senescence gene may be located on chromosome 10p15, especially at the D10S602, in gastric carcinogenesis, and that the putative gene malfunction may be involved in the early stages of gastric carcinogenesis.

Adult↗
PubMedDate not supplied

Somatic mutation in mitochondrial DNA and nuclear microsatellite instability in gastric cancer.

It was reported that somatic mutations in the mitochondrial DNA (mtDNA) are associated with high-frequency microsatellite instability (MSI-H) of the nuclear in gastric cancers. However, no correlation between mtDNA mutations and nuclear MSI-H was found in colorectal, breast, and renal cancers. Therefore, the association between mtDNA mutations and nuclear MSI-H in gastric cancers is controversial. We examined mtDNA mutations and nuclear MSI in a large panel of gastric cancers. One-hundred and five gastric cancers were selected. Mutations in the mononucleotide repeat (D310) of mtDNA and nuclear MSI at 5 microsatellite loci were examined by microsatellite assay. Somatic mutations in the mtDNA and nuclear MSI-H were detected in 16 (15%) and 14 (13%) of the gastric cancers, respectively. mtDNA mutations were detected in 2 of the 14 (14%) and 14 of the 91 (15%) tumors with and without nuclear MSI-H, respectively. There was no significant difference between them. These results suggest that somatic mutations in the mtDNA and nuclear MSI-H play important roles in gastric carcinogenesis, and that mtDNA mutations may not be associated with nuclear MSI-H in gastric cancers.

Adult↗
PubMedDate not supplied

Involvement of proinflammatory cytokines IL-1beta and IL-6 in progression of human gastric carcinoma.

UNLABELLED: Gastric carcinoma occurs in response to chronic inflammation of gastric mucosa infected with Helicobacter pylori. It is not known how cytokines affect the growth and progression of gastric carcinoma. MATERIALS AND METHODS: We measured tissue concentrations of the proinflammatory cytokines interleukin (IL)-1beta and IL-6 in gastric carcinoma and investigated the correlation between the levels of these cytokines and clinicopathological features. Biopsy specimens of tumors or adjacent normal mucosa were obtained from 42 Japanese patients with gastric carcinoma. Tissue levels of IL-1beta and IL-6 were measured by enzyme-linked immunosorbent assay. RESULTS: IL-1beta levels were significantly higher in the neoplasm than in the corresponding normal mucosa. The IL-6 levels in the neoplasm correlated significantly with the depth of invasion and lymphatic invasion. High levels of IL-1beta and IL-6 were characteristic of non-scirrhous type gastric carcinoma. CONCLUSION: These results suggest that IL-1beta and IL-6 are involved in the growth and progression of human gastric carcinoma.

Adult↗
PubMedDate not supplied

A novel intrahepatic arterial chemotherapy after radical resection for advanced hepatocellular carcinoma.

BACKGROUND/AIMS: Advanced hepatocellular carcinoma (HCC) with portal vein invasion and/or intrahepatic metastasis has an unfavorable prognosis even after radical hepatic resection. The aim of this study was to evaluate the effectiveness of a novel postoperative adjuvant chemotherapy given through the hepatic artery and based on biochemical modulation using cisplatin (CDDP) and 5-fluorouracil (5-FU). METHODOLOGY: Fifteen patients with advanced HCC with portal vein invasion into the main trunk and/or intrahepatic metastases of more than 3 segments were included in this study. After radical hepatic resection, the patients were divided to two groups: the adjuvant chemotherapy group (n=7) given the novel arterial infusion regimen with CDDP and 5-FU, and the control group (n=8) given no adjuvant chemotherapy. RESULTS: Three-year survival rate of the adjuvant chemotherapy group tended to be significantly longer compared to that for the control group (p < 0.05). Most of the tumor recurrence was in the remnant liver, 5 cases in both of the groups. Significant difference of the recurrence patterns was recognized, rather than difference of the disease-free survival rate between the two groups. All of the intrahepatic recurrences are multiple in the control group, but in the adjuvant chemotherapy group, 2 cases of the recurrences showed a localized tumor surgically resected. It is noteworthy that the occurrence of multiple recurrence was significantly later in the adjuvant chemotherapy group compared to the control group (18.9 months vs. 6.5 months; p<0.05). CONCLUSIONS: Our data suggest that this novel adjuvant chemotherapy can improve the postoperative prognosis of patients with the advanced HCC.

Aged↗
PubMedDate not supplied

Preoperatively undiagnosable intrahepatic bile duct dilatation contains early-stage intrahepatic cholangiocarcinoma.

Intrahepatic bile duct dilatation is a clue to indicating the presence of IHCC. Moreover it is still often difficult to find IHCC at an early stage in spite of recent progress in the area of molecular biological markers and imaging modalities. We had three interesting cases in which we were suspicious of the presence of IHCC. Preoperative imaging studies of these three cases showed the dilatation and stenosis of the intrahepatic bile duct without any apparent mass. As IHCC could not be ruled out, a hepatectomy was done for the purpose of both diagnosis and treatment of the patients. Postoperative diagnoses were IHCC in one, hepatolithiasis in another and chronic cholangitis in the third patient. A histological analysis revealed that the tumor of IHCC was not infiltrating the parenchyma of the liver with neither vascular nor lymphatic invasion, which suggested that it was an initial nature of the IHCC. In the case of intrahepatic bile duct dilatation and stenosis, which makes it hard to identify IHCC, surgical resection is crucial to make a definite diagnosis and prescribe the most effective course of treatment.

Abdominal Pain↗