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Biomedical subjects

M Makuuchi

Publications and source records attributed to M Makuuchi.

At least 253 records · Page 14Linked to original sources
PubMed1998

Staged hepatectomy after emergency transcatheter arterial embolization for ruptured hepatocellular carcinoma.

BACKGROUND: Staged hepatectomy after emergency transcatheter arterial embolization (TAE) has been advocated in ruptured hepatocellular carcinoma (HCC). However, there have been no reports of clinical series of this strategy. The purpose of this study was to evaluate the protocol of this therapeutic strategy. METHODS: Sixteen patients with suspected rupture of HCC were included in the study. After emergency TAE, tumor resectability was assessed, followed by staged hepatectomy or repeated TAE. The patients were reevaluated with regard to rupture of HCCs. RESULTS: Primary hemostasis was achieved successfully in all patients. Eleven patients were finally judged to have experienced HCC rupture. Seven of them underwent staged hepatectomy; the other four underwent repeated TAE because their tumors were considered unresectable. Survival time tended to be longer, but not to a significant extent, in patients who underwent hepatectomy (range, 139 to 1527 days; median, 375 days) than in those treated by TAE alone (range, 43 to 1317 days; median, 158 days). CONCLUSIONS: Staged hepatectomy after TAE is a rational treatment for patients with ruptured HCC. Although TAE is highly effective for initial hemostasis, hepatectomy appears to provide better long-term survival.

Adult↗
PubMed1997

Urgent living-related liver transplantation using a graft with multiple intrahepatic arterioportal fistulae.

BACKGROUND: We describe the case of a man with intrahepatic arterioportal fistulae located in the left lobe, whose left lateral segment was transplanted into his son who was suffering from severe acute hepatitis B. METHODS: A male infant with severe acute hepatitis B was considered to be a candidate for liver transplantation. The father was willing to be the donor. Preoperative evaluation of the donor revealed intrahepatic arterioportal fistulae, however, duplex ultrasonography showed normograde portal blood flow. A living-related liver transplantation was performed. RESULTS: The postoperative course for both the donor and recipient was uneventful. The recipient is free of recurrent hepatitis B and has normograde portal blood flow. CONCLUSIONS: The present case suggests that there may be a symptomless population with intrahepatic arterioportal fistulae, which cause various degrees of disruption of the portal blood flow. Duplex ultrasonography might be helpful in the evaluation of candidates for liver donation.

Adult↗
PubMed1997

Stimulated activation of platelet-derived growth factor receptor in vivo in balloon-injured arteries: a link between angiotensin II and intimal thickening.

BACKGROUND: Growth factors such as platelet-derived growth factor (PDGF) have been postulated to be important mediators of neointimal formation in balloon-injured artery. Binding of growth factors to their receptors activates intrinsic receptor tyrosine kinase, resulting in tyrosine phosphorylation of receptors themselves and cellular substrate proteins. We investigated in vivo activities of growth factors by determining the extent of tyrosine phosphorylation of growth factor receptors and substrate proteins in injured artery. METHODS AND RESULTS: Rat balloon-injured carotid artery was analyzed for phosphotyrosine content of PDGF alpha- and beta-receptors, epidermal growth factor (EGF) receptors, and insulin receptor substrate-1 (IRS-1) by immunoprecipitation and anti-phosphotyrosine Western blot. The development of intimal thickening after deendothelializing balloon catheterization of rat carotid artery was accompanied by transient twofold to threefold increases in the extent of tyrosyl phosphorylation of PDGF alpha- and beta-receptors but not EGF receptor or IRS-1. The AT1 angiotensin II (Ang II) receptor antagonist TCV-116 markedly inhibited both tyrosyl phosphorylation of PDGF alpha- and beta-receptors and intimal thickening. The AT1 antagonist reduced mRNA levels of both PDGF-A and -B chains in injured arteries. CONCLUSIONS: The present study provides direct evidence for increased PDGF activities in injured artery in situ and the involvement of Ang II in stimulated activation of PDGF receptors. These results are consistent with the pathogenetic role for PDGF in intimal thickening.

Amlodipine↗
PubMed1997

A simple method to confirm patency of the graft bile duct during living-related partial liver transplantation.

A bile duct stricture caused by an inadvertent ligation or suture during donor operation is rare, but not a negligible complication after living-related liver transplantation (LRLT). We present here a simple technique to prevent this kind of complication. Before bilioenteric anastomosis, a rod-shaped surgical probe was introduced into the bile ducts of the graft to examine their patency. The position of the surgical probe and the liver segment in which the probe proceeded was checked using ultrasonography. Using this technique in all of our 60 cases of LRLT, we have had no experience of this bile duct complication. We recommend this technique to be adopted in LRLT and split-liver transplantation to diminish the risk of biliary complications.

Adult↗
PubMed1997

Rapid postincubation endothelial retention by Dacron grafts.

Defining the most appropriate conditions for strengthening the retention of endothelial cells (ECs) by small-diameter prosthetic endothelialized grafts is indispensable to their clinical application. The incubation time after seeding is one of the most important factors in EC retention. The effects of different postincubation times (0, 2, 4, 8, 16, 24, and 36 hr) on EC monolayers on two different types of graft, fibronectin-coated expanded polytetrafluoroethylene (ePTFE) and collagen-coated knitted Dacron grafts (4 mm x 5 cm) were examined. In situ counting of ECs on the grafts was performed by light microscopy. The percentage cell retention was calculated by dividing the cell counts for grafts exposed to pulsatile flow for 90 min by those for control grafts. To characterize the EC coverage of the grafts, scanning electron microscopy was also performed. The average cell density of control grafts ranged from 5.59 +/- 1.1 to 6.69 +/- 1.5 x 10(4) cells/cm2 and did not differ according to the kind of graft or incubation time. The knitted Dacron grafts showed the maximal cell retention (88 +/- 5%) after incubation for 8 hr, whereas ePTFE grafts did so after 24 hr (83 +/- 6%). Scanning electron microscopic examination after incubation for 8 hr revealed that the density of human ECs on the surfaces of ePTFE and Dacron grafts differed, although there was no morphological difference between the ECs on the two types of graft. Knitted Dacron grafts achieved a high percentage retention in a shorter time than ePTFE grafts.

Blood Vessel Prosthesis↗
PubMed1997

Hepatic artery reconstruction in living donor liver transplantation from the microsurgeon's point of view.

Microvascular surgery for the reconstruction of the hepatic artery in living donor liver transplantation is discussed from the microsurgeon's point of view. A refined operative procedure to improve the safety of the anastomosis is described. In living donor liver transplantation, the hepatic artery of the graft is short and small, the operative site is deep and mobile, and the anatomic arrangement of the graft left hepatic artery may differ from that of the recipient's dilated hepatic artery. To create a safe anastomosis under these conditions, recipient arteries that were slightly smaller than the graft artery were dissected. Without the size discrepancy, and end-to-end anastomosis could be created. Some refinements to create a good operative field made the anastomosis easy. The apparatus and techniques used in free-flap transfer facilitated a clean anastomosis. We anastomosed 44 arteries in 40 patients undergoing living donor liver transplantation using microsurgical techniques. Neither a decrease in the arterial blood flow nor hepatic artery thrombosis was noted. The refined operative procedure we describe in this report can be used to overcome the problems associated with the hepatic artery anastomosis in living donor liver transplantation.

Adolescent↗
PubMed1997

Reduced gastric surface mucus layer in experimental portal hypertension.

The pathogenesis of portal hypertensive gastropathy has not yet been thoroughly elucidated. Changes in the gastric surface mucus layer in prehepatic portal hypertensive and cirrhotic rat models were studied by observing frozen sections fixed with formaldehyde vapor and stained with hematoxylin and eosin. We produced prehepatic portal hypertensive rats by partial ligation of the portal vein, and cirrhotic rats by prolonged administration of carbon tetrachloride (CCl4) and phenobarbital sodium. The thickness of the corporal and antral gastric surface mucus was significantly reduced in prehepatic portal hypertensive and cirrhotic rats compared with the values obtained in control rats for portal hypertension (subjected to sham operation) and control rats for cirrhosis (treated with phenobarbital but not CCl4). These results indicate that the hemodynamic changes associated with portal hypertension reduce the thickness of the gastric surface mucus layer and may be one of the causes of the gastropathy associated with portal hypertension.

Animals↗
PubMed1997

Impact of intraoperative ultrasonography on surgery for cystic lesions of the pancreas.

The impact of intraoperative ultrasonography (IUS) on surgery for cystic lesions of the pancreas (CLPs) has not been fully clarified. Twenty patients with CLPs, including 5 pseudocysts and 15 true cysts, were scanned intraoperatively to evaluate the utility and practicality of IUS for CLPs. In four of the five patients with pseudocysts and two with retention cysts, the operative procedures were performed under IUS guidance. In one with a pseudocyst, IUS showed that the cyst did not involve the pancreas, and subsequently cystectomy without pancreatic resection was necessary. In one of the two patients with mucin-producing cystadenocarcinomas, IUS demonstrated a skip lesion in the duct of the pancreatic tail, which contributed to changing the operative procedure from pancreatoduodenectomy to total pancreatectomy; in the other, IUS showed that the lesion was localized in the body of the pancreas, and subsequently segmental pancreatectomy was carried out instead of scheduled pancreatoduodenectomy or distal pancreatectomy. Thus in these three patients the operative procedures were changed in light of the IUS findings. In the remaining 11, although IUS visualized CLPs clearly, it added no new information relevant to the operations. We conclude that IUS contributes to performing surgery for certain types of CLP, such as pseudocysts with severe inflammation, retention cysts with nonpalpable or invisible small cysts, mucin-producing cystadenocarcinomas, and possibly other lesions.

Cystadenocarcinoma, Mucinous↗
PubMed1997

Uric acid changes in serum during different forms of hepatic vascular inflow occlusion.

The present study was conducted to develop an efficient marker which can evaluate the influence of the occlusion of hepatic vascular inflow, which technique is commonly used in major liver surgery or in liver transplantation. Serum samples from the rats induced by hepatic vascular inflow occlusion were analyzed with high performance liquid chromatography with the electrochemical detection, and a substance which changed in accordance with the duration of the occlusion was obtained. Both the retention time and the ultraviolet absorption spectra of the substance completely agreed with those of an authentic uric acid and the substance was ultimately determined to be uric acid. To evaluate the changes in serum uric acid during different forms of hepatic vascular inflow occlusion we devised the four types of experimental model, viz. the occlusion of hepatic artery, portal vein, both hepatic artery and portal vein and both hepatic artery and portal vein of left hepatic lobes. From the device of experiments our results indicated that in the early stage of hepatic vascular inflow occlusion the high values of serum uric acid did not reflect the damage of hepatic circulation but rather responded to the intestinal congestion. Our results also indicated that even after the declamping of hepatic vascular inflow if high values of serum uric acid are prolonged it means the deterioration of the portocaval circulation including both intestinal and hepatic circulation. So that the evaluation of the severity of injured liver due to hepatic vascular inflow occlusion should be done with the caution especially in vivo study when uric acid values are used as a marker.

Animals↗
PubMed1997

Effect of anti-intercellular adhesion molecule-1 and anti-leukocyte function associated antigen-1 monoclonal antibodies on rat-to-mouse cardiac xenograft rejection.

BACKGROUND: The interaction between intercellular adhesion molecule-1 (ICAM-1) and its ligand, leukocyte function associated antigen-1 (LFA-1), is especially relevant in allograft rejection. We have previously shown that the simultaneous blockade of ICAM-1 and LFA-1 by monoclonal antibodies (mAbs) results in specific immunologic tolerance to cardiac allograft in a mouse model. METHODS: We evaluated the roles of these adhesion molecules in xenograft rejection by using a rat-to-mouse concordant xenograft model to identify critical molecules for immunosuppression. RESULTS: Lewis rat hearts transplanted into C3H/He mice were rejected within 5 to 7 days without treatment. A significant prolongation of xenograft survival (mean survival time, 11.6 days) was observed after treatment with anti-rat ICAM-1 and anti-mouse LFA-1 mAbs, when compared with nontreated mice or mice treated with different combinations of mAbs. Graft survival was prolonged in mice treated with FK506 (1 mg/kg/day), anti-rat ICAM-1, and anti-mouse LFA-1 mAbs (mean survival time, 22.2 days), whereas the same dose of FK506 alone was not effective. The mixed lymphocyte reaction showed that a combination of mAbs against mouse LFA-1-rat ICAM-1 and rat LFA-1-mouse ICAM-1 significantly inhibited the proliferation of mouse responders to rat stimulators and rat responders to mouse stimulators, respectively. Infiltration of mouse CD4 positive, mouse CD8 positive, and mouse LFA-1 positive cells, as well as dense deposition of mouse immunoglobulin G (IgG), IgM, and up-regulation of rat ICAM-1, on the graft endothelial cells were demonstrated by immunopathologic analysis of the rejected hearts. Flow cytometric analysis with rat spleen cells demonstrated the presence of xenoreactive antibodies (mouse IgG and IgM) in the recipient's serum. This xenoreactive antibody production was delayed but not inhibited by treatment of the recipients with anti-rat ICAM-1 and anti-mouse LFA-1. CONCLUSIONS: Blockade of the donor side ICAM-1 and the recipient side LFA-1 is critical for immunosuppression with anti-ICAM-1-LFA-1 treatment. Humoral factors may be responsible for xenograft rejection that occurs even after inhibition of the cell-mediated immune response by anti-ICAM-1 and anti-LFA-1 mAbs.

Animals↗
PubMed1997

Adenovirus-mediated transfer of tissue-type plasminogen activator gene to human endothelial cells.

BACKGROUND: Seeding of vascular grafts with genetically engineered human endothelial cells (hECs) secreting antithrombogenic or fibrinolytic agents has considerable clinical potential. METHODS: An adenoviral vector was used to transfer the human tissue-type plasminogen activator (htPA) gene to hECs, and the ability of the transduced hECs to secrete htPA was examined. Cultured hECs on plates were incubated with various concentrations of recombinant adenoviruses containing the htPA or LacZ gene for various times to determine the optimal transfer conditions. Transduced hECs were seeded onto fibronectin-coated expanded polytetrafluoroethylene grafts (4 mm in diameter), some of which were exposed to pulsatile flow in vitro. RESULTS: Effective transduction of the htPA gene into hECs (htPAhECs) was achieved with viral soup at a multiplicity of infection of 30 after incubation for 1 day, which yielded 4.8 +/- 0.20 x 10(3) ng/10(6) cells/6 hr htPA antigen on plates (n = 3), 2.2 +/- 2.0 x 10(3) ng/10(6) cells/6 hr on grafts (n = 6), and 6.8 +/- 1.7 x 10(2) ng/10(6) cells/6 hr on perfused grafts (n = 6). The retention of htPAhECs by perfused grafts was 84.0% +/- 3.0%, comparable with the noninfected (82.1% +/- 8.0%) and mock-infected (94.2% +/- 0.4%) hEC values. CONCLUSIONS: By adenoviral vector-mediated gene transfer, 10(2-3)-fold enhancement of htPA secretion was demonstrated, which did not affect cell retention by grafts.

Adenoviridae↗
PubMed1997

Ruptured abdominal aorta secondary to psoas muscle abscess due to Klebsiella pneumoniae in an alcoholic.

An alcoholic patient with low back pain and Klebsiella pneumoniae septicaemia is reported. Computed tomography revealed abdominal aortic rupture associated with a psoas abscess. Aortic ligation above and below the rupture site and an axillo-femoral bypass were performed, but the patient died on the first postoperative day. Alcoholism is a common underlying disease in K. pneumoniae septicaemia and its septic metastasis to the psoas muscle. The prognosis of aortic infection secondary to psoas abscess is very poor once aortic rupture occurs. Prompt abscess drainage following correct diagnosis and arterial reconstruction before aortic rupture are mandatory.

Adult↗
PubMed1997

Increased expression of vascular endothelial growth factor in human hepatocellular carcinoma.

BACKGROUND/AIMS: Angiogenesis is critical for the development and progression of solid tumors. The purpose of this study was to evaluate the possible role of vascular endothelial growth factor (which is considered to be one of the most important factors involved in tumor-associated angiogenesis), in human hepatocellular carcinoma. METHODS: Vascular endothelial growth factor gene and protein expression were analyzed by means of Northern hybridization and immunohistochemical methods in 5 hepatocellular carcinoma cell lines. Secretion of vascular endothelial growth factor was evaluated by immunoblotting of conditioned medium of these hepatocellular carcinoma cells. Further, we compared the level of vascular endothelial growth factor expression in hepatocellular carcinoma tissues along with that in surrounding tumor-free tissues obtained from 20 patients. We also analyzed mRNA expression of Flt-1, one of the vascular endothelial growth factor specific high-affinity receptors, in hepatocellular carcinoma cell lines. RESULTS: Northern hybridization analysis and immunohistochemistry revealed that all cultured hepatocellular carcinoma cells exhibited a high level of vascular endothelial growth factor mRNA. In addition, vascular endothelial growth factor secretion by Hep G2, one of the hepatocellular carcinoma cell lines, was shown by Western blot. In vivo, we observed vascular endothelial growth factor expression in both hepatocellular carcinoma and non-hepatocellular carcinoma tissues. However, in 12 of 20 cases, vascular endothelial growth factor mRNA levels were significantly up-regulated in hepatocellular carcinoma tissues. In the majority of cases (10 out of 12 cases) with abundant tumor vascularity, vascular endothelial growth factor mRNA up-regulation in hepatocellular carcinoma tissues was observed. We failed to detect Flt-1 mRNA expression in hepatocellular carcinoma cells. CONCLUSIONS: This study suggests that the possibility that hepatocellular carcinoma cells overexpress the vascular endothelial growth factor gene and protein. These findings support the hypothesis that vascular endothelial growth factor is one of the important factors involved in the angiogenesis of hepatocellular carcinoma, and may even be involved in the development and/or progression of hepatocellular carcinoma itself.

Adolescent↗
PubMed1997

Intraoperative evaluation of small-calibre arterial reconstructions.

A new hammerhead-shaped, small probe for intraoperative duplex ultrasound was devised to evaluate small-calibre arterial reconstructions. This probe was used in two patients; one with terminal liver cirrhosis who had a left hepatic lobe that had been transplanted from her mother, and a second patient with limb-threatening ischaemia who had undergone arterial reconstructions. The technique was diagnostically useful and contributed to successful clinical outcomes.

Adolescent↗
PubMed1997

Heterogeneity of DNA content in multiple synchronous hepatocellular carcinomas.

Heterogeneity of DNA content in multiple hepatocellular carcinomas (HCCs) was investigated by flow cytometry in 62 tumours from 26 patients who had undergone surgical treatment for multiple synchronous HCCs. Heterogeneity of DNA content was defined (a) when tumours had a different DNA ploidy pattern or (b) when the difference in the DNA index of the aneuploid clone was more than 0.1. A tumour with DNA aneuploidy was observed in 17 (66%) of the 26 patients. Heterogeneity of the DNA content was demonstrated in 12 (46%) out of 26 patients: in ten cases by definition (a) and in two cases by definition (b). Histological examination revealed that, of the 12 patients with a heterogeneous tumour DNA content, seven (58%) had a heterogeneous and the remaining five (42%) had a homogeneous type and grade of differentiation among the tumours, showing the absence of a relationship between histological heterogeneity and DNA content. The present results suggest the clinical relevance of DNA content analysis for identifying the clonal origin of multiple HCCs.

Aged↗