Effect of platelet inhibition on experimental venous thrombosis in the rabbit

An experimental model, based on a combination of endothelial damage and flow reduction, was used to induce thrombosis of the jugular vein in rabbits. The influence of ibuprofen, a cyclooxygenase inhibitor, was compared with that of dextran 70, which influences platelets, thrombus structure and flow. Albumin was used as a control of the volume-expanding effect of dextran. Ibuprofen was administered intravenously during the induction of thrombosis, and dextran and albumin were given 3 hours before the surgical procedure. Control rabbits received only Ringer's lactate. Dextran, but neither ibuprofen nor albumin, significantly reduced the incidence of thrombosis, though thrombus weight was not influenced. The data indicated that the effect of dextran in this model probably is primarily exerted via alteration of thrombus structure, and not by altered platelet function or hemodilution. The role of platelets in the initial development of thrombosis in this model thus may be questioned.     

Heparinized human umbilical vein grafts. Delayed heparin desorption after alcohol treatment

Tanned human umbilical vein grafts (Dardik Biograft, Meadox) were heparinized with tritium-labelled heparin. Two methods of heparinization were undertaken: (1) incubation with heparin followed by ethyl alcohol 50% treatment, and (2) incubation with heparin without alcohol. Grafts were placed in the carotid arteries of sheep and removed 10 and 90 days later. Heparin was lost in contact with blood but the alcohol treatment delayed heparin desorption significantly.     

Correlation of serum HCV RNA and alanine aminotransferase levels in chronic hepatitis C patients during treatment with ribavirin

to evaluate the effect of ribavirin on serum hepatitis C virus (HCV) RNA and alanine aminotransferase (ALT) levels, 22 patients with chronic HCV infection were treated with oral ribavirin 1200 mg daily in three divided doses for 4 weeks. At the end of 4 weeks treatment, the serum ALT decreased in all but one patient and became normal in three individuals. The mean pretreatment serum ALT was reduced significantly from 193 ± 45 i.u./L to 95 ± 16 i.u./L after 4 weeks therapy (P= 0.009). However, 8 weeks after cessation of treatment, the serum ALT rose to a mean value of 154 ± 21 i.u./L. The mean pretreatment serum HCV RNA was not significantly decreased at the end of 4 weeks treatment (7.0 × 10⁵vs 4.1 × 10⁵ copies/mL, P > 0.05). However, serum HCV RNA levels were decreased in 12 and increased in 10 patients at the end of 4 weeks therapy. Eight weeks after cessation of therapy, the serum HCV RNA of 22 patients rose to a mean value of 4.9 ± 10⁵ copies/mL. Six patients who continued to have elevated serum ALT and positive HCV RNA after the initial 4 weeks treatment received oral ribavirin at the same dosage for an additional 24 weeks. The serum ALT again decreased in all six patients during therapy, but rose to pretreatment values by 8 weeks after cessation of the treatment. In addition, no significant changes were noted in the mean serum HCV RNA levels during and after 24 weeks of ribavirin therapy. Our results indicate that oral ribavirin only transiently lowered serum ALT values and did not efficiently suppress HCV synthesis in patients with chronic hepatitits C infection.     

Analysis of clinical variables associated with tolerance in pediatric liver transplant recipients

Tolerance has been defined as stable graft function off IMS. We reviewed the data of 369 pediatric liver transplant patients to examine demographic differences that may have a PV of pediatric LT tolerance. Of the 369 patients, 280 patients were stable with detectable blood levels of IMS agents and with good graft function without biopsy proven REJ > 1 yr posttransplantation, 18 patients were noted to be TOL off IMS, 27 patients were taking MIS with drug levels below detectable range by standard laboratory parameters, and 44 patients developed one or more episodes of biopsy proven acute or chronic REJ > 1 yr post-transplantation. Variables, including percentage of biliary atresia, type of transplanted organ, history of EBV infection, patient and donor gender, and ABO blood type mismatch between recipient and donor did not have PV of tolerance. Average age in years was 1.37 ± 1.53 (0.3-4.9) for TOL, 1.14 ± 0.89 (0.4-3.1) for MIS and 3.35 ± 4.45 (0.3-16) for REJ. Age difference of TOL/MIS vs. REJ was significant (p =0.002) and TOL vs. REJ was significant (0.01). Age at the time of transplantation is an important predictor in the development of pediatric LT tolerance.     

A review of abdominal organ transplantation in cystic fibrosis

Lu BR, Esquivel CO. A review of abdominal organ transplantation in cystic fibrosis.
Pediatr Transplantation 2010: 14:954–960. © 2010 John Wiley & Sons A/S. Abstract: With advances in medical treatments, patients with CF are having improved quality of life and living longer. Although pulmonary disease is still the leading cause of morbidity and mortality, this longevity has allowed for the development of other organ dysfunction, mainly liver and pancreas. This review discusses the abdominal organ complications and the role of abdominal organ transplantation in CF. Liver failure and portal hypertension complications are the most common indicators for liver transplantation in CF, and five‐yr survival for isolated liver transplantation is >80%. Deficiency of pancreatic enzymes is almost universal and up to 40% of patients with CF can develop insulin‐dependent diabetes, although the role of pancreas transplantation is less clear and needs further research. Finally, the need for lung transplantation should always be assessed and considered in combination with liver transplantation on a case‐by‐case basis.