Significance of Portal Venous Velocity in Short-term Graft Function in Living Donor Liver Transplantation

BACKGROUND

Graft regeneration and functional recovery after reperfusion of transplanted graft are very important for successful living donor liver transplantation (LDLT). The aim of this study was to evaluate the significance of postoperative portal venous velocity (PVV) in short-term recovery of graft function in LDLT.

PATIENTS AND METHODS

From February 2007 through December 2015, we performed 17 primary LDLTs, which were included in the present study. The patients ranged in age from 12 to 65 years (mean: 50 years), and 11 were female patients. Postoperatively, Doppler ultrasonography was performed daily to measure PVV (cm/s), and liver function parameters were measured daily. The change in PVV (ΔPVV) was defined as follows: ΔPVV = PVV on postoperative day (POD) 1 - PVV on POD 7. Maximal value of serum aspartate aminotransferase (ASTmax) and maximal value of serum alanine transaminase (ALTmax) at 24 hours after graft reperfusion were used as parameters of reperfusion injury. Correlation analyses were performed as follows: (1) correlation of ΔPVV and PVV on POD 1 (PVV-POD 1) with the values such as ASTmax, ALTmax, other liver function parameters on POD 7 and graft regeneration rate; (2) correlation of ASTmax and ALTmax with other liver function parameters on POD 7.

RESULTS

ΔPVV significantly correlated with the values of serum total bilirubin (P < .01), prothrombin time (P < .01), and platelet count (P < .05), and PVV-POD 1 significantly correlated with the values of serum total bilirubin (P < .05) and prothrombin time (P < .05).

CONCLUSION

ΔPVV and PVV-POD 1 may be useful parameters of short-term functional recovery of the transplant liver in LDLT.

Living-related liver transplantation in Diego blood group disparity: a case report

To date, only limited cases of Diego blood group disparity in liver transplantation have been reported, and no cases with a long-term clinical course have been documented. Herein, we report a case of Diego blood group disparity in liver transplantation with details of long-term follow-up. The recipient was a 47-year-old woman with primary biliary cirrhosis; her 18-year-old daughter was the donor. Both recipient and donor were of blood type O according to the ABO blood group system. Preoperative serological tests showed the presence of antibodies against the Di(a) antigen only in the recipient, and not in the donor. Thus, the Diego phenotype was Di(a+) in the donor and Di(a-) in the recipient. Living-related liver transplantation was performed in July 2009. Immediate graft function was obtained, and no signs of humoral or cellular rejection were observed during the postoperative period. Further, anti-Di(a) antibodies were not detected throughout the postoperative course. The patient is alive and shows no signs of humoral rejection 34 months after liver transplantation. Liver transplantation has been performed successfully in cases of Diego blood group disparity.

A phase I study of full-dose gemcitabine and regional arterial infusion of nafamostat mesilate for advanced pancreatic cancer

BACKGROUND

The primary end points of this study were to determine the dose-limiting toxic effects (DLTs), maximum tolerated dose, and a recommended phase II dose of a synthetic serine protease inhibitor, nafamostat mesilate, in combination with full-dose gemcitabine in patients with unresectable locally advanced or metastatic pancreatic cancer. The secondary end point was to assess therapeutic response.

PATIENTS AND METHODS

Patients with previously untreated pancreatic cancer received gemcitabine (1 000 mg/m(2) i.v. for 30 min) on days 1, 8, and 15, with nafamostat mesilate (continuous regional arterial infusion for 24 h through a port-catheter system) on days 1, 8, and 15; this regimen was repeated at 28-day intervals. The initial dose of nafamostat mesilate was 2.4 mg/kg and was escalated in increments of 1.2 mg/kg until a dose of 4.8 mg/kg was achieved. A standard '3+3' phase I dose-escalation design was used. Therapeutic response and clinical benefit response were assessed.

RESULTS

Twelve patients were enrolled in this study. None of the patients experienced DLTs, and nafamostat mesilate was well tolerated at doses up to 4.8 mg/kg in combination with full-dose gemcitabine. This combination chemotherapy yielded a reduction of a high serum level of the tumor marker CA19-9. Pain was reduced in three of seven patients without oral morphine sulfate. Overall survival was 7.1 months for all patients.

CONCLUSION

This phase I study was carried out safely. This combination chemotherapy showed beneficial improvement in health-related quality of life. The recommended phase II dose of nafamostat mesilate in combination with full-dose gemcitabine is 4.8 mg/kg.

Clinicopathological significance of EZH2 mRNA expression in patients with hepatocellular carcinoma

Enhancer of zeste homologue 2 (EZH2), a member of the polycomb group protein family, plays a crucial role in the regulation of embryonic development and has been associated with the regulation of the cell cycle. Recently, several studies have shown that EZH2 is highly expressed in aggressive tumours, including human breast cancer, prostate cancer, and lymphomas. We thus analysed EZH2 expression using real-time reverse transcription-polymerase chain reaction, and correlated its expression status with various clinicopathological parameters in 66 patients with hepatocellular carcinoma (HCC). We found high expression of EZH2 in human liver cancer cell lines. Furthermore, EZH2 gene-expression levels in tumour tissue specimens (0.34+/-0.52) were significantly higher (P<0.0001) than those in the corresponding nontumour tissue specimens (0.07+/-0.09). The incidence of cancer cell invasion into the portal vein was significantly higher (P<0.001) in the high EZH2 expression group (26 of the 33, 79%) than in the low expression group (13 of the 33, 39%). However, there was no significant difference in the disease-free survival rate between the two groups. The findings of this study indicate that EZH2 mRNA expression was upregulated in human HCC and may play an important role in tumour progression, especially by facilitating portal vein invasion.

[A remarkably improved multimetastatic gastric cancer with the use of TS-1 and CDDP]

A 62-year-old male presented to our hospital with jaundice. On the abdominal ultrasound and abdominal CT, there was evidence of multiple, massive liver metastases with dilatation of intrahepatic bile ducts, thickened wall of the stomach from the body to the antrum, direct invasion to the pancreas, multiple lymph node metastases, and ascites. We believed it was Stage IV and too far advanced for surgery. Therefore, ST-1 60 mg bid was started, and CDDP 50 mg was infused in the seventh week. On the follow-up CT and ultrasound three months later, the thickening of the gastric wall and the lymph node metastasis had improved and the border between the stomach and the pancreas had become clearer. The liver metastases seen on both lobes had decreased significantly both in size and number. The dilatation of the intrahepatic bile ducts disappeared, and the liver function normalized. No side effects were evident during the treatment with the medications.

Genetic control of the humoral responses to xenografts. III. Identification of the immunoglobulin V(H) genes responsible for encoding rat immunoglobin G xenoantibodies to hamster heart grafts

BACKGROUND

We have previously reported that the early phases of the immune response of rats to hamster xenografts are characterized by the production of IgM xenoantibodies encoded by a restricted group of Ig germline V(H) genes (V(H)HAR family). In the later phases of the reaction, an IgM to IgG isotype switch occurs and our study examines the structure of the rearranged V(H)HAR genes used to encode IgG antibodies after this isotype switch.

METHODS

A quantitative polymerase chain reaction was used to investigate the changes in the levels of V(H)HAR+ IgG mRNA seen after xenotransplantation. cDNA libraries specific for V(H)HAR+ Iggamma chain were established from total RNA extracted from splenocytes of naive rats and xenograft recipients of hamster hearts at days 4, 8, 21, and 28 posttransplantation. Colony filter hybridization was used to estimate the relative frequency of the use of individual V(H)HAR+ IgG subclasses. Selected IgG clones from day 21 cDNA libraries were sequenced and analyzed for VH-D-J(H) gene usage and antibody combining site structure.

RESULTS

The level of mRNA for V(H)HAR+ IgG increased 6-fold in xenograft recipients at day 21 post-transplantation when compared with naive animals. The relative frequency of isotype usage for V(H)HAR+ IgG1 antibodies alone increased from 22.3% at day 0 to 37.4% at day 21 PTx. Ten IgG clones from the day 21 cDNA libraries have been sequenced for the rearranged V(H)-D-J(H) genes. Thirty percent (3/10) of these IgG clones used V(H)HAR genes for the coding of heavy chain variable region with limited numbers of nucleic acid substitutions (>98% identity with their germline progenitors) although others demonstrated increased variation in nucleotide sequences (95-97% identity) when compared with germline V(H) genes. Analysis of the canonical binding site structure from the predicted amino acid sequences demonstrated that the majority of IgG clones (9/10) displayed a similar pattern of conserved configurations for their combining sites.

CONCLUSIONS

The change in IgM to IgG antibody production in the later stages of the humoral immune response of rats to hamster xenografts is associated with an IgM to IgG isotype switch and an increased production of antibodies of the IgG1 isotype. Rat anti-hamster IgG xenoantibodies continue to express the V(H)HAR family of V(H) genes, many in their original germline configuration, to encode antibody recognition of the hamster target antigens. There are, however, a majority of antibodies for which the V(H) genes express evidence of increased nucleic acid sequence variation when compared to currently available germline sequences. The source of this variation is not known but may represent the expression of as yet unidentified germline genes and/or the introduction of T cell-driven somatic mutations. Despite the appearance of this variation, the unusual level of conservation in key antigen binding sites within the V(H) region suggests the variation, independent of its origin, may have a limited influence on the restricted nature of the host antibody response to xenografts.

The mechanism of hepatic graft protection against reperfusion injury by prostaglandin E1

The purpose of this study was to evaluate the effect of prostaglandin E1 (PGE1) on protecting against hepatic endothelial cell damage and increasing graft viability after cold preservation and reperfusion, using an isolated perfused rat liver (IPRL) model. The grafts were divided into three groups, according to the cold preservation time and PGE1 administration, namely: 4h preservation (group 1, n = 9), 6h preservation (group 2, n = 9), and 6h preservation followed by PGE1 infusion (group 3, n = 9). After cold storage, the grafts were put on the recirculating IPRL system, then reperfused for 120 min at 37 degrees C with oxygenated Krebs-Henseleit buffer containing hyaluronic acid (HA). To examine the function of the sinusoidal endothelial cells and hepatocytes, serial measurements of HA, tumor necrosis factor-alpha (TNFalpha), thromboxane B2 (TXB2), acid phosphatase, and conventional parameters in the perfusate were made. After perfusion, the trypan blue exclusion test was performed to assess the presence of any microscopic sinusoidal lining cell damage. In group 3, the bile output and HA clearance were significantly greater, while glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, TNFalpha, TXB2, and acid phosphatase in the perfusate were significantly lower than in group 2. Histologically, less endothelial cell damage and hepatocyte damage than in group 2 was also confirmed. These results therefore suggest that the improvement of hepatic graft viability by PGE1 administration is mainly due to sinusoidal endothelial cell protection.

The humoral response to xenografts is controlled by a restricted repertoire of immunoglobulin VH genes

BACKGROUND

The early phases of the host immune response to xenografts are dominated by anti-donor antibodies. The immunological pathways responsible for mediating the host humoral responses to xenografts are largely unknown, and this report addresses the nature of the immunoglobulin genes controlling the host antibody response to xenografts.

METHODS

cDNA libraries established from rat anti-hamster monoclonal antibodies and splenic lymphocytes from LEW rats rejecting hamster heart xenografts were used to clone, sequence, and identify the immunoglobulin genes responsible for encoding rat xenoantibodies to hamster heart grafts. Libraries for germline variable region heavy chain (VH) genes encoding the anti-hamster xenograft antibodies were established by genomic DNA cloning and analyzed by nucleotide sequencing. The frequency of Ig VH gene usage for controlling the antibody responses to hamster xenografts was examined by colony-filter dot hybridization. The nucleic acid structure of these genes was then compared to their genomic progenitors to identify the number and structural diversity expressed by the Ig VH genes used to mediate the response.

RESULTS

Rat monoclonal antibodies selected for their ability to precipitate the rejection of hamster xenografts exclusively use a closely related group of VH genes. The VH genes used by these antibodies are restricted to a single family of germline genes (VHHAR) for which 15 family members have been identified. The frequency of VHHAR gene usage in splenic IgM-producing B cells from LEW rats rapidly expands from 0.8% in naive animals to 13% in recipients 4 days after xenotransplantation. cDNA libraries expressing VHHAR genes were established from splenic lymphocytes derived from naive or xenograft recipients at 4 and 21 days after transplantation. Examination of 20 cDNA clones revealed that the majority (75%) of these clones express VHHAR genes displaying limited somatic mutation.

CONCLUSIONS

The use of a closely related group of Ig VH genes in a germline configuration to control the early humoral response to xenografts suggests that this response may represent the utilization of a primitive, T cell-independent pathway of antibody production by the graft recipients.

Heterotopic gastric mucosa in a gallbladder with an anomalous union of the pancreatobiliary duct: a case report

A 25 year-old woman experienced a sudden onset of epigastralgia with nausea, and consulted our hospital. Because the abdominal pain did not subside with medication, she was hospitalized. On physical examination she had a slight tenderness of the right upper abdominal quadrant. Laboratory studies disclosed increases in the serum alkaline phosphatase, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and serum amylase levels. Abdominal ultrasonography, computed tomography, and endoscopic retrograde cholangiopancreatography revealed choledocholithiasis and a pancreatic duct which originated from the common bile duct. A common bile duct stone was removed with a basket catheter after an endoscopic sphincterotomy was performed. Since an anomalous union of a pancreatobiliary duct is a high risk factor of gallbladder cancer, laparoscopic cholecystectomy was perfomed. The post-operative course was uneventful and she was discharged on the twentieth post-operative day. In a microscopical examination of the resected specimen, a pyloric type gastric mucosa was clearly evident in the submucosa, while the remaining gallbladder demonstrated chronic cholecystitis. Some cases of heterotopic gastric mucosa in the gallbladder come from metaplasia, and metaplasia is also one of the most important factors in the carcinogenesis of gallbladder cancer. In conclusion, the present case is the first report of gastric mucosa with an anomalous union of the pancreatobiliary duct. Heterotopic gastric mucosa in the gallbladder may be one of the causes of gallbladder cancer, and close attention should, therefore, be paid to any occurrence of heterotopic gastric mucosa in this region.

Significance of donor nutritional status for rewarming injury of the hepatic graft in rats

We studied the significance of donor nutritional status for hepatic rewarming injury and the usefulness of the glucagon loading test for the assessment of donor nutritional status in rats. In experiment 1, the animals were either free fed or fasted for 6, 24 or 48 h. The livers were preserved in chilled lactated Ringer's solution for 4 h and were divided into eight groups according to the fasting and rewarming periods. The ammonia level in the graft effluent was increased in grafts preserved for 24 h or longer, which was augmented when rewarming time was increased from 15 to 30 min (p < 0.05). In experiment 2, the animals were divided into four groups (n = 3 each) according to the fasting period. The hepatic tissue glycogen content was measured after fasting, and the serum glucose was measured after the administration of 50 micrograms/kg of glucagon i.v. The hepatic tissue glycogen content correlated with the increase rate of serum glucose (p = 0.0001). We conclude that glycogen may protect the hepatic graft from rewarming injury by improving energy status, particularly in prolonged rewarming. The glucagon loading test seems to be useful for assessing the glycogen content of the hepatic graft.

Reduction of rewarming injury of the hepatic graft by a heat insulator

BACKGROUND

The deleterious effect of rewarming in orthotopic liver transplantation is recognized. This study examined the significance of rewarming the hepatic allograft, and the possibility of using a heat insulator to reduce rewarming injury.

METHODS

After total hepatectomy in rats with in situ perfusion by chilled (4 degrees C) lactated Ringer's solution, the livers were divided into four groups of ten each: group 1, 4-h preservation in chilled Ringer's solution and 15 min of rewarming; group 2, 6-h preservation in chilled Ringer's solution; group 3, 6-h preservation in chilled Ringer's solution and 15 min of rewarming; group 4, 6-h preservation in chilled Ringer's solution and 15 min of rewarming with a heat insulator. Glutamic-pyruvic transaminase (GPT) and N-acetyl-beta-glucosaminidase (NAG) concentrations in the final graft effluent, and the amount of adenosine 5'-triphosphate (ATP) in liver tissue after preservation, were measured.

RESULTS

GPT and NAG concentrations in the final graft effluent of group 3 were higher than those of group 2 (P < 0.01), whereas values in group 4 were lower than those of group 3 (P < 0.05). The final ATP concentration in group 3 was significantly lower than that in group 2 (P < 0.01), whereas the value in group 4 was significantly higher than that of group 3 (P < 0.01).

CONCLUSION

Rewarming diminishes the viability of a liver graft with degradation of ATP, and a heat insulator reduces rewarming injury.

Lupus peritonitis mimicking acute surgical abdomen in a patient with systemic lupus erythematosus: report of a case

A 25-year-old Japanese woman who had been suffering from systemic lupus erythematosus (SLE) for 12 years was admitted to our hospital with a suspected diagnosis of peritonitis after suddenly developing severe abdominal pain and distention which could not be relieved by treatment with anodyne. Noninvasive examinations did not provide enough evidence to rule out acute appendicitis, bowel perforation, or ischemia due to vasculitis. Therefore, in consideration of the severity of her uncontrollable abdominal pain, an exploratory laparotomy was performed. The operative findings revealed nonbacterial peritonitis with a large amount of ascites and an edematous small bowel. No perforation of the intestine was found. On post-operative day (POD) 3, the severe abdominal pain redeveloped, but responded well to steroid pulse therapy. Based on the operative findings and her clinical course, the most likely diagnosis was thought to be acute lupus peritonitis. It is often difficult to ascertain whether abdominal pain in an SLE patients is due to lupus peritonitis or to an underlying cause requiring surgery. Thus, it is essential that continuous and careful assessment of the surgical abdomen is performed when a patient with SLE develops acute abdominal pain, and if a surgical condition cannot be ruled out, a laparotomy should be performed without delay.

Assessment of hepatic graft injury by graft effluent in rodents: N-acetyl-beta-glucosaminidase and type III procollagen peptide

We studied the significance of N-acetyl-beta-glucosaminidase (beta-NAG) and type III procollagen peptide (P-III-P) in the effluent of rodent hepatic grafts. After total hepatectomy, the livers were preserved in chilled, lactated Ringer's solution and then divided into five groups (n = 10 each): group 1, 4 h preservation only; group 2, 4 h preservation and rewarming; group 3, 6 h preservation only; group 4, 6 h preservation and rewarming; and group 5, minimal preservation only. The beta-NAG of groups 2 and 4 was significantly higher than that of groups 1 and 3 (0.98 +/- 0.5 U/l vs 0.21 +/- 0.12 U/l; P < or = 0.01 and 1.76 +/- 0.67 U/l vs 0.38 +/- 0.25 U/l, respectively; P < or = 0.01), while that of group 4 was significantly higher than that of group 2 (1.76 +/- 0.67 U/l vs 0.98 +/- 0.50 U/l; P < or = 0.05). The P-III-P of group 4 was significantly higher than that of group 2 (0.133 +/- 0.008 U/ml vs 0.110 +/- 0.015 U/ml; P < 0.01). We conclude that beta-NAG is a novel parameter of parenchymal and nonparenchymal cells, while P-III-P reflects the integrity of the hepatic sinusoidal extracellular matrix.

Serum hyaluronic acid as a reliable parameter of allograft viability in porcine liver transplantation

BACKGROUND/AIMS

Hyaluronic acid is an endogenous glycosaminoglycan which is selectively degraded by hepatic sinusoidal endothelial cells. We evaluated the significance of serum hyaluronic acid clearance as an early indicator of allograft viability in porcine liver transplantation.

MATERIALS AND METHODS

According to the survival period, animals were divided into two groups: Group I (n = 8) for survival equal or over four days and Group II (n = 5) for survival less than four days. Serial serum hyaluronic acid concentrations were measured before and after reperfusion in the recipient.

RESULTS

In both groups, serum hyaluronic acid levels during the anhepatic period increased rapidly 9-fold from the preoperative value due to the absence of clearance by hepatic endothelial cells. In Group I, serum hyaluronic acid peaked at 15 min postreperfusion and decreased thereafter. In contrast, Group II failed to show clearance of hyaluronic acid after reperfusion. The serum hyaluronic acid value 120 min after reperfusion was 1,029 +/- 357 micrograms/L in Group I, and 1,856 +/- 263 micrograms/L in Group II (p < 0.01). Conventional parameters of liver function such as aspartate transaminase, lactic dehydrogenase, ammonia, lactate, and total bile acids were comparable between the two groups.

CONCLUSIONS

The clearance of the serum hyaluronic acid reflects hepatic sinusoidal endothelial cell function and is a reliable and early marker of hepatic allograft viability.

Significance of hyaluronic acid for evaluation of hepatic endothelial cell damage after cold preservation/reperfusion

Serum hyaluronic acid (HA) levels during or after liver transplantation can reflect graft viability in animal models. Decreased HA clearance in nonviable grafts seems to reflect hepatic endothelial cell damage induced by cold preservation/reperfusion. Therefore, we examined the relationship between HA clearance and endothelial cell damage, using an isolated perfused rat liver (IPRL) model. The grafts were separated into four groups, according to cold preservation time: minimal storage (

CONTROL

n = 9), 4-hr preservation (n = 9), 5-hr preservation (n = 8), 6-hr preservation (n = 9). After cold storage, grafts were put on the recirculating IPRL system and then reperfused for 120 min with 37 degrees C oxygenated Krebs-Henseleit buffer, containing HA and sodium taurocholate. To examine the function of sinusoidal endothelial cells and hepatocytes, serial measurements of HA, total bile acids, and conventional parameters in the perfusate were taken. After the perfusion, a trypan blue exclusion test was done to assess the microscopic sinusoidal lining cell (SLC) damage. HA clearance from the perfusate showed a preservation time-dependent decrease which clearly distinguished between 4- and 6-hr preserved grafts. Trypan blue uptake ratio of SLC increased in accordance with preservation time. HA clearance at 120 min after reperfusion showed a highly significant correlation with histologically assessed SLC damage. These results suggest that HA is useful to evaluate the extent of endothelial cell damage after cold storage and reperfusion. The significance of HA as a predictor of graft viability is also confirmed.

Hepatitis C virus infection among Japanese general surgical patients

The incidence of hepatitis C virus (HCV) antibody positivity is unknown. The purpose of this study was to clarify the prevalence of HCV infection among surgical patients and to identify high risk surgical patients. HCV antibody tests were performed in 789 surgical patients between April 1991 and March 1992. Of these patients, 129 (16.3%) tested positive, which was much higher than the positivity of the ordinary Japanese. Hepatobiliary diseases and portal hypertension were associated with a higher positivity than other disease categories (94 of 206, 45.6% versus 35 of 583, 6%; p < 0.0001). Patients above 50 years of age had a higher positivity than their younger counterparts (118 of 578, 20.4% versus 11 of 211, 5.3%; p < 0.0001). The HCV positivity was as high as 54.1% (119 of 220) among surgical patients with known risk factors for hepatitis, in contrast to only 1.9% (10 of 569) among those without such risk factors. We conclude that surgical patients have a high incidence of HCV infection, for whom medical professionals should pay special attention to avoid disease transmission.

Serum hyaluronic acid for the assessment of graft viability in porcine liver transplantation

For the assessment of graft viability, serum hyaluronic acid (HA) levels during porcine orthotopic liver transplantation were measured in two groups: group 1 (viable: n = 5) in which allografts were transplanted following a minimal cold (4 degrees C) preservation, and group 2 (nonviable: n = 4) in which allografts were transplanted after cold static storage (4 degrees C) for 24 h in University of Wisconsin solution. The changes in the HA levels reached a significant difference between the two groups at 30 min after reperfusion (P < 0.02). In group 1, all animals survived for over 4 days, while all animals in group 2 died within 24 h. The serum HA also demonstrated a significant correlation with prothrombin time, beta-glucuronidase, and aspartate aminotransferase at 120 min after reperfusion. These results suggest that the measurement of serum HA is a potentially effective index for evaluating hepatic allograft viability.

The significance of tissue-type plasminogen activator for pretransplant assessment of liver graft viability: analysis of effluent from the graft in rats

We studied the significance of tissue-type plasminogen activator (tPA) on the pretransplant assessment of liver graft viability in rats. The liver grafts were excised from the rats and then divided into two groups. Group 1 consisted of grafts preserved for 4 h in chilled, lactated Ringer's solution (4 degrees C) and group 2 consisted of grafts preserved for 6 h in the same solution. After preservation, the liver grafts were flushed out through the portal vein using 5 ml of chilled, lactated Ringer's solution (4 degrees C). The entire effluent from the hepatic veins was then collected and analyzed for tPA, ammonia, lactate, pyruvate, glutamic oxaloacetic transaminase, and lactate dehydrogenase. The tPA concentration of effluent in group 2 was significantly higher than that in group 1 (0.80 +/- 0.23 ng/ml vs 0.42 +/- 0.08 ng/ml, P < 0.05). The lactate, pyruvate, and ammonia levels in group 2 were also higher than those in group 1 (134 +/- 13 mg/dl vs 120 +/- 2 mg/dl, 0.34 +/- 0.40 mg/dl vs 0.09 +/- 0.01 mg/dl, and 183 +/- 79 micrograms/dl vs 102 +/- 40 micrograms/dl, respectively). However, the discriminative power of tPA was stronger than that of the other parameters. Histological findings revealed a higher number of trypan blue-stained sinusoidal lining cells that were detached and swollen in group 2. We conclude that the amount of tPA in the effluent flushed from the graft can serve as a sensitive and reliable indicator of cold-preserved liver grafts in rats.

A safe and simple technique for exchanging central venous catheters

A safe and simple technique for exchanging central venous catheters is herein described. Our technique is based on a modification of Seldinger's method, in which a new outer sheath is introduced over the previous catheter as a guidewire in order to simplify the exchange of central venous catheters. This technique can be successfully performed by new residents and can be applied to the exchange of clotted catheters.