Mataro Goto

Technique for orthotopic reduced-size hepatic transplantation combined with ex vivo liver cut down in the rat

A technique is described for orthotopic reduced-size hepatic transplantation combined withex vivo liver cut down in the rat. Following perfusion of the donor liver with cold heparinized saline, the portal veins, bile ducts, and hepatic arteries to the median and left lobes together were dissectedin situ, encircled, and divided. After harvesting the donor liver, a hepatectomy was performed byex vivo liver cut down of the median and left lobes. The remnant amounted to 32% of the whole liver. As a result, the suprahepatic vena cava could be well visualized with adequate exposure for vascular anastomosis. Orthotopic reduced-size hepatic transplantation was performed using the right and caudate lobes of the liver. The suprahepatic vena cava was anastomosed with a 7-0 silk running suture. A simplified cuff without processes was made with an obliquely cut polyethylene tube and used for the portal and infrahepatic caval anastomoses. A Teflon tube stent was used for the biliary anastomosis. The newly devised angled clamp and flexible arm were used for the cuff attachment and operative procedure. Transplant survival followingex vivo liver cut down was as good as that with whole liver transplantation. Reestablishment of the hepatic artery restores liver function following transplantation. The maximum hepatocyte labeling index (LI) occurs 24 hr after a 68% hepatectomy, and at 36 hr following a reduced-size hepatic transplantation with or without hepatic arterialization. Possible explanations for the slight delay in achieving the maximal LI may include damage that is induced by the operation itself, pregraft preservation, and reperfusion injuries. In conclusion, the anatomical features of the hepatic lobes in rats are well suited to successful completion ofex vivo liver cut down.

Phenotype And Localization Of Macrophages Expressing Inducible Nitric Oxide Synthase In Rat Hepatic Allograft Rejection

BACKGROUND We investigated the phenotype and localization of macrophages expressing inducible nitric oxide synthase (iNOS) in rat hepatic allografts, using double immunostaining with anti-macrophage iNOS (macNOS) and rat anti-macrophage (ED1 or ED2) monoclonal antibodies. METHODS The animals were divided into three experimental groups: group 1, isografts; group 2, untreated hepatic allografts; and group 3, hepatic allografts treated with FK506. RESULTS Plasma nitrite/nitrate concentrations in group 2 increased on day 3, peaked on day 5, and decreased thereafter. In contrast, the plasma nitrite/nitrate concentrations in group 1 increased slightly on day 3, but decreased gradually thereafter. The plasma concentrations of nitrite/nitrate did not vary in group 3. The peak nitrite/nitrate values in group 2 were significantly greater than those in groups 1 and 3. The number of macNOS+ cells peaked on day 5 in group 2. In contrast, a few macNOS+ cells were seen in the liver grafts of groups 1 and 3. Double immunostaining revealed that the macNOS+ cells consisted of macNOS+ ED1+ (80%) and macNOS+ ED2+ (40%) in the untreated hepatic allografts on day 5. In addition, a number of macNOS+ cells also were seen in the red pulp of the recipient spleen in the untreated hepatic allografts. CONCLUSIONS These results suggest that the intense iNOS expression by the monocyte/macrophage lineage among the hepatic infiltrates and by the splenic macrophages after transplantation supports a role for nitric oxide in the immunomodulation of allogeneic responses in local and remote organs, and possibly serves as a mediator of cytotoxic graft damage.

Neutrophil elastase inhibitor (ONO-5046) decreases cytokine-induced neutrophil chemoattractant after reperfusion of pancreaticoduodenal transplantation in rats.

The protective effects of a neutrophil elastase inhibitor (ONO-5046) on reperfusion injury following pancreaticoduodenal transplantation in rats were studied by measuring serum concentrations of cytokine-induced neutrophil chemoattractant (CINC). Male Wistar rats were transplanted with syngeneic pancreaticoduodenal grafts. ONO-5046 was injected intravenously 5 min before vascular clamping and immediately after reperfusion at a dose of 10 mg/kg. No significant differences were observed in the peak serum concentrations of amylase between the groups treated with and treated without ONO-5046. The serum lipase concentrations in the untreated animals increased and peaked 3 hr after reperfusion. ONO-5046 significantly decreased the peak serum lipase concentration. The serum CINC concentrations, which were determined by enzyme-linked immunosorbent assay, increased and peaked 3 hr after reperfusion, decreasing gradually thereafter. However, pretreatment with ONO-5046 significantly inhibited the rise in serum CINC concentrations after reperfusion. Expression of CICN transcripts in the pancrease grafts was evaluated by Northern blot analysis and peaked 3 hr after reperfusion in untreated animals. Pretreatment with ONO-5046 also significantly inhibited the expression of CINC mRNA transcripts in the graft. ONO-5046 significantly decreased the number of neutrophils accumulated in the pancreas graft 24 hr after transplantation. In vitro CINC production by peritoneal macrophages was increased by neutrophil elastase in dose-dependent fashion. However, ONO-5046 decreased CINC production by peritoneal macrophages in response to neutrophil elastase. These results suggest that ONO-5046 prevents early neutrophil accumulation in the pancreas following ischemia/reperfusion of pancreaticoduodenal transplantation.

Calcium-channel blocker attenuates Kupffer cell production of cytokine-induced neutrophil chemoattractant following ischemia-reperfusion in rat liver.

We investigated the effects of the calcium-channel blocker verapamil hydrochloride on the production of cytokine-induced neutrophil chemoattractant (CINC) following reperfusion injury in rat liver. Ischemia was induced for 30 min by portal vein occlusion. Animals were pretreated with intravenous injection of verapamil hydrochloride (2.5 mg/kg) 5 min before vascular clamp. Verapamil hydrochloride limited increases in the chemoattractant compared with nonpretreated rats. Most cells immunostained for chemoattractant were ED2-positive macrophages in sinusoids. In vitro chemoattractant production by Kupffer cells isolated from animals pretreated with verapamil hydrochloride was significantly lower than by Kupffer cells from nonpretreated animals. Expression of transcripts in liver for chemoattractant peaked 3 hr after reperfusion in nonpretreated animals, while pretreatment with verapamil hydrochloride significantly decreased chemoattractant mRNA levels. In vitro chemoattractant production could be induced in naive Kupffer cells after stimulation with oxygen radicals generated by hypoxanthine and xanthine oxidase, but verapamil hydrochloride prevented these increases. We concluded that the calcium-channel blocker verapamil hydrochloride significantly attenuates chemoattractant release by Kupffer cells after ischemia–reperfusion in the rat liver.

Effect of cyclosporine on liver regeneration after orthotopic reduced-size hepatic transplantation in the rat

These experiments were undertaken to study the effects of cyclosporine A (CsA) on liver regeneration after an isogeneic orthotopic reduced-size hepatic transplantation (RSHT) in rats. Male Wistar rats were treated with or without a daily injection of CsA beginning 24 hr before surgery and were subjected to a 68% partial hepatectomy. A isogeneic orthotopic reduced-size hepatic transplantation was performed in recipient rats pretreated with or without CsA. A daily injection of CsA was continued until the recipient rats were sacrificed. Animals were sacrificed at various time points (12, 24, 36, 48, and 72 hr) postoperatively. The incorporation of bromodeoxyuridine (BrdU) into the DNA of the remnant hepatocytes was evaluated by immunohistochemical staining with a monoclonal antibody against BrdU. CsA (10 mg/kg/day) significantly augmented BrdU incorporation into hepatocytes after hepatectomy. The maximum labeling index (LI) was observed at 24 hr after hepatectomy. In contrast, the maximum LI in the recipient rats not receiving CsA was seen at 36 hr after RSHT, and 10 mg/kg/day of CsA decreased the LI at 36 hr after RSHT. A lower dose of CsA (3 mg/kg/day), however, significantly increased the LI in the recipient rats (P<0.01), and it reached a peak at 24 hr after RSHT when compared to the transplant recipients not receiving CsA. The time course of the increase in the LI in the transplant recipient rats receiving 3 mg/kg/day of CsA was similar to that observed in the rats after hepatectomy. This dosage improved the delay in the reduced-size hepatic transplant LI reaching its peak. These findings suggest that after RSHT the liver graft is more sensitive to both hepatotrophic and hepatotoxic effects of CsA.

Risk factors for catheter-related bloodstream infections in adult hospitalized patients — multicenter cohort study

Abstract Background: Risk factors for catheter-related bloodstream infections (CRBSIs) may change over time with progress in infection control. This study was undertaken to explore the current risk factors for CRBSIs in hospitalized patients. Methods: Adult patients with non-tunneled central venous catheters (CVCs) in 12 Japanese referral hospitals were prospectively enrolled between December 2009 and January 2012. Patients were monitored for CRBSIs for up to 8 weeks from CVC insertion; data were collected regarding patient characteristics, the purpose of CVC insertion, insertion methods, mechanical complications during insertion, and post-insertion catheter care. Results: A total of 892 patients were enrolled in this study. The overall incidence of CRBSIs was 0.40 infections per 1000 catheter-days. Univariate analysis using the Fishers exact test identified one of the participating hospitals (hospital A; p < 0.001), internal jugular vein catheterization (IJVC) (p = 0.0013), not using maximal sterile barrier precautions (p = 0.030), and the Seldinger technique for catheter insertion (p = 0.025) as significant risk factors for CRBSI. After excluding data from hospital A, only IJVC remained a significant risk factor for CRBSI (p = 0.025). The cumulative probability of remaining without CRBSI was significantly lower in patients with IJVCs than in patients with other catheter routes (p < 0.001; log-rank test). Similarly, the cumulative probability of remaining without catheter removal due to a suspected infection was significantly lower in patients with IJVCs (p = 0.034; log-rank test). Conclusions: The current study suggests that IJVC might be a risk factor for CRBSI under current infection control conditions.

Recombinant Human Hepatocyte Growth Factor Facilitates Biliary Transport After Hepatocyte Transplantation in Eisai Hyperbilirubinemic Rats

Hepatocyte transplantation may offer anattractive treatment for inborn errors of livermetabolism. However, factor(s) are required as stimulito induce proliferation of the limited number ofhepatocytes transplanted. The Eisai hyperbilirubinemic rat(EHBR) is a SpragueDawley (SD) mutant rat withconjugated hyperbilirubinemia. EHBRs have impairedcanalicular excretory transport of organic anions, bileacid glucuronide, and sulfate. Recombinant humanhepatocyte growth factor (rhHGF) (100 μg/kg) wasinjected intravenously at 2-hr intervals for 10 hr,immediately and 35 days following the intraportalinjection of 1 × 107 wild-type SD rathepatocytes. Serum bilirubin concentrations decreasedsignificantly within 35 days and were maintained atsignificantly reduced levels for 120 days followingtransplantation. Biliary excretion was demonstrated by the biliarytransport of indocyanine green and sulfobromophthaleinsodium into the bile. These results indicate thathepatic transport of bile acid conjugates in EHBRs can be restored by hepatocyte transplantationcombined with repeated administration of exogenousrhHGF, in conjunction with functioning of therecipients excretory biliary system.

A significant reduction of macrophages expressing inducible nitric oxide synthase in rat hepatic allografts pretreated with donor-specific blood

BACKGROUND A single intravenous injection of donor-specific blood (DST) 7 days before transplantation significantly prolongs survival of hepatic allografts from fully allogeneic ACI(RT1a)-->LEW(RT1(1)) rats. The aim of this study was to investigate the kinetics of nitric oxide synthesis by macrophages in rat hepatic allografts treated with DST. METHODS We investigated macrophages expressing inducible nitric oxide synthase in animal group I (receiving isografts), group II (hepatic allografts), and group III (hepatic allografts after donor-specific blood). RESULTS Serum nitrite/nitrate, interferon-gamma, and tumor necrosis factor-alpha concentrations increased significantly in group II for 7 days after transplantation but were significantly much lower in groups I and III. Numbers of macrophages immunostained with an anti-macrophage nitric oxide synthase monoclonal antibody and inducible nitric oxide synthase mRNA levels in liver specimens also were much lower in groups I and III than in group II. In addition, Northern blot analysis demonstrated abundant interleukin-10 mRNA transcripts in the DST-treated hepatic allografts compared to untreated allografts. Double immunostaining revealed anti-macrophage synthase-containing cells, including both ED1+ and ED2+ cells, in liver and spleen as more numerous in group II. CONCLUSIONS Inducible nitric oxide synthase is suppressed in immunologic unresponsiveness to grafts after donor-specific blood transfusion.