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Mitsuo Shimada

Publications and source records attributed to Mitsuo Shimada.

At least 109 records · Page 6Linked to original sources
PubMed2002

Sequential hemodynamic change in hepatocellular carcinoma and dysplastic nodules: CT angiography and pathologic correlation.

OBJECTIVE: The purpose of this study was to clarify the hemodynamic changes associated with hepatocarcinogenesis using CT angiography. MATERIALS AND METHODS: Eighty-six hepatocellular lesions were confirmed at pathology in 49 patients who underwent CT with both hepatic arteriography and arterioportography. These images were compared with lesion-to-liver vascular ratios of cumulative arteries, preexisting hepatic arteries, and portal veins in resected specimens. Lesions were classified in five groups according to intranodular hemodynamics determined by CT hepatic arteriography and CT during arterioportography: group 1, isoattenuating on both procedures; group 2, hypoattenuating on CT hepatic arteriography and isoattenuating on CT during arterioportography; group 3, hypoattenuating on both procedures; group 4, isoattenuating on CT hepatic arteriography and hypoattenuating on CT during arterioportography; and group 5, hyperattenuating on CT hepatic arteriography and hypoattenuating on CT during arterioportography. RESULTS: Among 86 lesions, we identified seven low-grade dysplastic nodules, eight high-grade dysplastic nodules, 14 well-differentiated hepatocellular carcinomas, 45 moderately differentiated hepatocellular carcinomas, and 12 poorly differentiated hepatocellular carcinomas. The lesions were classified as group 1 (n = 5), group 2 (n = 13), group 3 (n = 6), group 4 (n = 2), or group 5 (n = 60). Intranodular hemodynamics was significantly correlated with pathologic grading (p < 0.001). For correlations between combinations of the groups and pathologic gradings, the order "groups 1-2-3-4-5" was the most significant (p < 0.001). CONCLUSION: During hepatocarcinogenesis, most hepatocellular nodules show deterioration of arterial blood flow before loss of portal blood flow. Vascular imaging of hepatic nodules may predict malignant abnormality via the early loss of hepatic arterial flow seen before portal flow changes.

Aged↗
PubMed2002

Dose-dependent effect of dietary conjugated linoleic acid on the growth of rat hepatoma dRLh-84 cells in vivo.

In this study, the effect of varying doses of conjugated linoleic acid (CLA) on the growth of transplanted hepatoma dRLh-84 cells and the relationship between tumor growth and prostaglandin (PG) E2 production or cyclooxygenase (COX)-2 expression were examined. Donryu rats were fed an experimental diet containing 0, 0.1, 0.5, or 2 wt.% CLA for 3 wk, and then dRLh-84 cells were transplanted into the liver. Results show that dietary CLA (0.5 and 2 wt.%) significantly enhanced the growth of the transplanted hepatoma cells compared to the non-CLA diet group at 20 d after cell transplantation. Tumor weight at 10 d after transplantation was also significantly higher in the 2 wt.% CLA group than in non-CLA fed rats. Ten days after transplantation, the PGE2 level in the tumor tissue was shown to be depressed in a CLA dose-dependent manner. Cyclooxygenase-2 (COX-2) mRNA expression in the tumor also tended to be lower in the CLA group than in the non-CLA diet group 10 d after transplantation. Dietary CLA did not affect the tumor phospholipid arachidonic acid level, which is a substrate for PG synthesis. These results indicate that dietary CLA of at least 0.5 wt.% enhances the growth of transplanted dRLh-84 cells in vivo. It is believed that growth promotion of dRLh-84 cells in vivo by CLA cannot be clarified by the PG synthesis dependent mechanism.

Animals↗
PubMed2002

[An ideal liver support system and xenotransplantation].

Currently, the rapid increase in the number of candidates for orthotopic liver transplantation has resulted in a shortage of donor organs and, especially for fulminant hepatic failure, an urgent need for transplantations. Thus the need for a liver support system as a "bridge" before liver transplantation is also urgent, as is the need for treatment of reversible acute liver disease. Various liver support systems have been proposed, for example, cross-circulation systems, extracorporeal liver support systems, hemodialysis, and hemadsorption, but these are not considered to function sufficiently. Demetriou's system, Sussman's system, and Gerlach's system have reached clinical trials. The ideal liver support system should have significant metabolic capacity, the ability to be used in continuous treatment, simplicity of use, biocompatibility, ready availability, consistency, economy, and safety from viral infection, but no system meets all of these criteria.

Animals↗
PubMed2002

[Future aspect of robotic surgery].

Minimally invasive surgery has become a standard options of surgery. We have introduced a master-slave manipulator "da Vinci" to the clinical situation in July 2000, and developed new operative techniques, which are safer and more tender for patients than before. Up to now, a total of 45 patients underwent a robot-assisted endoscopic surgery using "da Vinci" system. Several procedures including laparoscopic splenectomy and thoracoscopic mediastinal tumor extirpation were first performed in the world. This system provided surgeons with motion scaling, physiological tremor elimination, and high-resolution 3-dimensional vision. Thanks to those sophisticated functions, all surgical procedures, which have been limited due to endoscopic circumstances, were performed much easily and safely than before. Every effort to develop a new type of robotic has been made in collaboration with other fields of scientists. A next-generation robotic surgery is required to equip new functions including tactile sensation system, a real-time navigation system and tele-operation system. Robotic surgery is believed to be one of the most promising and important fields of surgery in the near future.

Forecasting↗
PubMed2002

High metabolic function of primary human and porcine hepatocytes in a polyurethane foam/spheroid culture system in plasma from patients with fulminant hepatic failure.

It has been demonstrated that plasma from patients with fulminant hepatic failure (FHF) interferes extensively with cellular function. We placed primary human and primary porcine hepatocytes in a polyurethane foam (PUF)/spheroid culture system and compared the metabolic functions in the plasma of patients with FHF in a 24-h stationary culture to those in a monolayer culture. The PUF/spheroid culture system using primary human and primary porcine hepatocytes significantly decreased ammonia content during 28-day culture. Fisher's ratio significantly increased at culture days 3 and 7. Tauroursodeoxycholic acid significantly increased and glycochenodeoxycholic acid and taurochenodeoxycholic acid decreased in the FHF patients' plasma at culture day 3. During at least a 24-h culture in the FHF patients' plasma, metabolic functions of primary human and primary porcine hepatocytes were almost identical. The present results indicate that the PUF/spheroid culture system using primary human or primary porcine hepatocytes demonstrated more advantageous metabolic functions in the plasma from patients with FHF than the monolayer culture.

Ammonia↗
PubMed2002

[Living donor liver transplantation for fulminant hepatic failure--medical treatment organization in Kyushu University].

Liver transplantation has been recognized as an effective therapeutic method for end-stage liver disease in Japan. Fulminant hepatic failure is also an indication for liver transplantation, and the number of patients undergoing liver transplantation has been increasing. Reversibility and urgency are characteristics of fulminant hepatitis. If given appropriate critical support, many patients recover spontaneously. However, many patients develop cerebral edema or multiorgan failure before the liver can regenerate. From October 1996 to July 2002, living donor liver transplantation (LDLT) was performed to 84 end stage liver disease patients in Kyushu University. Twenty-four (28.6%) of 84 LDLTs were for fulminant hepatic failure. In Kyushu University, LDLT candidates including urgent cases were discussed with indication in the liver transplantation committee (the medical professions division and an outside-the-university committee are included) and then the coordinator committee performs informed consent. LDLT can be performed only by cooperation of each section concerned such as Transfusion part, Medicine part, Radiation part, Operation part, Intensive Care Unit and so on. In this paper, we outline about fulminant hepatic failure and living donor liver transplantation, and describe the fulminant hepatitis medical treatment organization in Kyushu University.

Humans↗
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↗
PubMed2002

[Living donor liver transplantation for a patient with renal failure].

Pretransplant renal failure is a well-known risk factor which adversely affects the prognosis after liver transplantation. We report a case with pretransplant renal failure and discuss the perioperative management of such patient. The patient was 62 year-old-woman who was diagnosed with end-stage liver disease due to primary biliary cirrhosis, for which living donor liver transplantation (LDLT) was indicated. Her pretransplant serum creatinine was 9.4 mg/dl due to combination of drug-induced (antibiotics) acute tubular necrosis and hepatorenal syndrome. The management of renal failure consisted of the avoidance of calcineurin inhibitor as an induction immunosuppression and the use of perioperative continuous hemodiafiltration (CHDF). The postoperative course of the patient was complicated with CMV pneumonia and acute rejection, however she recovered and discharged on 94 POD with well-preserved graft function and normal renal function without any adverse sequela. LDLT for patients with renal failure can be performed successfully by careful management.

Acute Kidney Injury↗
PubMedDate not supplied

Comparison of test-injection method and fixed-time method for depiction of hepatocellular carcinoma using dynamic steady-state free precession magnetic resonance imaging.

OBJECTIVE: The purpose of this study was to clarify the usefulness of the test-injection method as compared with the fixed-time method in dynamic magnetic resonance (MR) imaging of hepatocellular carcinoma (HCC). METHODS: Ninety-seven patients with a total of 118 hepatocellular carcinomas underwent 3-dimensional fast imaging with steady-state free precession (3D-FISP) for dynamic study of the liver as well as catheter-assisted computed tomography hepatic angiography (CTHA) for preoperative evaluation. In 42 cases, the fixed-time method (30-second scan time delay in the hepatic arterial phase [HAP]) was performed (group 1), and in 55 cases, the test-injection method was performed (group 2). The following parameters were evaluated: 1) the adequacy of the HAP, 2) tumor vascularity using CTHA findings as a gold standard, and 3) the contrast-to-noise ratio (CNR) of the HCC during the HAP of dynamic MR imaging. RESULTS: In group 1, 79% (33 of 42) of the cases were obtained at the optimal HAP; the percentage in group 2 was 98% (54 of 55) of the cases. This difference was statistically significant (P < 0.05). The vascularity of 82% of the tumors in group 1 and 89% of those in group 2 was diagnosed correctly. Regarding hypervascular tumors, correct evaluation of tumor vascularity was made in 87% of group 1 cases and 95% of group 2 cases. No significant difference was present between the 2 groups (total: P = 0.43, hypervascular HCC: P = 0.29). 3) The CNR calculated for all HCCs in group 2 (mean +/- SD: 8.66 +/- 11.0) was significantly higher than that for HCCs in group 1 (4.29 +/- 9.44; P < 0.05). As for the hypervascular tumors, the CNR calculated for group 2 (mean +/- SD: 9.89 +/- 10.6) was also significantly higher than that for group 1 (5.52 +/- 9.81; P < 0.05). CONCLUSION: The 3D-FISP dynamic MR imaging using the test-injection method resulted in better demonstration of HCC than the 3D-FISP using the fixed-time method.

Adult↗
PubMedDate not supplied

Detecting postsurgical recurrent hepatocellular carcinoma with multiphasic helical computed tomography: intrahepatic metastasis or multicentric occurrence?

OBJECTIVE: The aim of this study was to assess the computed tomography (CT) patterns of postoperative recurrent hepatocellular carcinoma (HCC). METHODS: Of 84 patients with histologically proven HCC by hepatectomies, multiphasic helical CT demonstrated 54 HCC lesions of intrahepatic recurrence in 31 (37%) patients. The initial and final appearances of HCC on hepatic arterial phase images were retrospectively determined by the serial CT scans, which were compared with appearances of primary HCC. RESULTS: The initial appearances of 54 recurrent HCCs were identical to the appearances of primary HCC in 41 (76%) lesions. Serial changes from the initial appearance to the final appearance of recurrent HCC were observed in 10 (42%) of 24 lesions. The 13 discordant lesions and the 10 lesions with altered lesion vascularity in our series implied that at least 43% were of multicentric occurrence. CONCLUSION: More than 40% of postoperative recurrent HCCs show intranodular hemodynamic changes. The incompatibility between CT findings of primary and recurrent HCCs implies that these tumors contain nodules of multicentric occurrence.

Adult↗
PubMedDate not supplied

The Sialyl Lewis X expression in hepatocarcinogenesis: potential predictor for the emergence of hepatocellular carcinoma.

BACKGROUND/AIMS: Sialyl Lewis X (sLeX), one of the cancer-associated glycoproteins, has been reported to be expressed in both liver tissue from various types of liver disease and hepatocellular carcinoma. In order to clarify sLeX expression during the early stage of hepatocarcinogenesis, we examined sLeX expressions in either liver tissue specimens without any nodular lesions, dysplastic nodules or hepatocellular carcinomas. METHODOLOGY: Immunohistochemical observations were performed using a monoclonal antibody for sLeX. As for the liver tissue specimens, 8 livers without any chronic liver disease and 42 diseased livers were examined, while for the nodular lesions, 5 dysplastic nodules (borderline lesions) and 47 hepatocellular carcinomas were examined in this study. RESULTS: sLeX was not expressed in all 8 normal livers. sLeX was expressed membraneously in 8 of 15 (53%) chronic hepatitic liver tissue specimens, in 8 of 9 (89%) precirrhotic liver tissue specimens and in 16 of 18 (89%) cirrhotic liver tissue specimens. The incidence of sLeX expression on hepatocytes in both pre-cirrhotic and cirrhotic liver tissue was higher than that in chronic hepatitic liver tissue (P < 0.05). The sLeX expression in liver tissue was positive in all 14 liver tissue specimens containing multiple hepatocellular carcinomas, in which at least one of the nodules was a well-differentiated hepatocellular carcinoma regarded as multicentric hepatocellular carcinomas. In 18 of 28 (64%) liver tissue specimens without multicentric hepatocellular carcinomas, sLeX was positive and the difference was statistically significant (P < 0.05). In nodular lesions, sLeX was negative in 5 dysplastic nodules (borderline lesions). In hepatocellular carcinoma, 14 of 47 (30%) hepatocellular carcinoma nodules showed a positive expression. Six of 14 (43%) well-differentiated hepatocellular carcinomas were positive on the cell membrane. Four of 23 (17%) moderately differentiated hepatocellular carcinomas were positive on the cell membrane, while one of 23 (4%) moderately differentiated hepatocellular carcinoma was positive in the cytoplasm. In addition, 3 of 10 (30%) poorly differentiated hepatocellular carcinomas were positive in the cytoplasm. CONCLUSIONS: These results suggested that the sLeX-positive liver tissue specimens possessed a high degree of carcinogenicity and therefore sLeX expression in the diseased liver might be a good predictor for hepatocellular carcinoma emergence. At the same time, the suppression of sLeX occurred at a very early stage of hepatocarcinogenesis. In addition, the phenotype of sLeX was also considered to change during the progression of hepatocarcinogenesis.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

A comparison of right-lobe and left-lobe graft for living-donor liver transplantation.

BACKGROUND/AIMS: The practice of living-donor liver transplantation has been widely established. However, in adult cases, the issue of graft liver volume has been raised. Recently, liver transplantation using the right lobe has been done in cases requiring a larger graft volume. We compared right lobectomy with left lobectomy for hepatocellular carcinoma not accompanied by liver cirrhosis and examined the safety of hepatic right lobectomy for donation. METHODOLOGY: In total, 124 hepatocellular carcinoma patients without liver cirrhosis, 89 who had undergone right hepatectomy and 35 who had undergone left hepatectomy, were studied. For each group, we statistically examined the patients' profiles. RESULTS: The resected right lobe was significantly heavier than the left lobe. There were significant differences between the two groups in terms of the number of blood transfusions needed. Moreover, delayed recoveries in terms of hemoglobin, total bilirubin, and clotting disorder on postoperative day 7, as well as the frequency of any complications, were more prevalent in the right-lobe group. CONCLUSIONS: It was confirmed that right lobectomy is more invasive than left lobectomy. It is necessary to prioritize the donor's safety and quality of life in living-donor liver transplantation, and adequate medical and ethical consideration is demanded.

Adolescent↗
PubMedDate not supplied

Morphologic approach to hepatocellular carcinoma development in man: de novo or the so-called 'dysplastic nodule-carcinoma' sequence?

The so-called dysplastic nodule-carcinoma sequence in the liver is generally accepted because hepatocellular carcinoma is not an uncommon finding in precancerous lesions. In order to evaluate the existence and frequency of de novo hepatocarcinogenesis we studied 112 surgically resected early well-differentiated hepatocellular carcinomas showing replacing growth without less differentiated component in themselves. They were divided into two groups: carcinoma in dysplastic area (type A) and carcinoma without dysplastic area (type B) and were analyzed clinicopathologically. We encountered 77 cases of type A (68.8%) and 35 of type B (31.2%). The frequency of type A in cirrhotic group (74.7%) is statistically higher than that of non-cirrhotic group (54.5%) (p=0.0453). Using multivariate analysis, the occurrence of type A was related with higher age, the presence of cirrhosis and hepatitis B surface antigen positive. The tumor size and the presence of fatty change in the tumor tended to relate with type A. We propose two pathways morphologically in early hepatocarcinogenesis, one of which has a close relation to hepatitis B virus and/or cirrhosis.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Optimal multi-phase three-dimensional fast imaging with steady-state free precession dynamic MRI and its clinical application to the diagnosis of hepatocellular carcinoma.

PURPOSE: To determine the appropriate acquisition parameters for three-dimensional fast imaging with steady-state free precession (3D-FISP), to clarify the superiority of 3D-FISP to two-dimensional fast low-angle shot (2D-FLASH) on phantom study, and to clarify the clinical usefulness of 3D-FISP in diagnosing hepatocellular carcinoma (HCC). MATERIALS AND METHODS: 3D-FISP images with varying flip angles were compared by using a phantom. Signal-to-noise ratios (SNRs) and contrast-enhancement ratios (CERs) were compared for the four two-dimensional fast low-angle shot (2D-FLASH) sequences and 3D-FISP sequences in a phantom. The optimal 3D-FISP dynamic study was compared with plain, postcontrast MR sequences used to study 78 HCC cases and analyzed according to histological grade. The 3D-FISP image obtained 30 sec after gadopentetate dimeglumine (Gd) administration was also compared with CT hepatic angiography (CTHA). RESULTS: A 25 degrees flip angle and double-dose Gd administration were appropriate for 3D-FISP dynamic study. CER was the highest with 3D-FISP, and SNR was higher in 3D-FISP than in 2D-FLASH images in a phantom with high Gd concentration. Among the 105 lesions, 103 (98%) were depicted on 3D-FISP images. The detection rate of HCC on 3D-FISP was higher than 95% for each histological grade. The vascularity of the tumors as determined by CTHA findings was correctly diagnosed on 3D-FISP in 80% of cases. CONCLUSION: In phantom study, 3D-FISP with double-dose Gd injection showed higher contrast than 2D-FLASH as a sequence for liver dynamic study. In clinical study, 3D-FISP is useful in the detection of HCC, regardless of tumor vascularity and histological grade.

Carcinoma, Hepatocellular↗
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↗