Analysis of Risk Factors for Allograft Outcome Comparing 2 Kidneys From the Same Donor in Separate Recipients.

BACKGROUND: An analysis of 2 kidney transplants from the same donor at the same center enables us to analyze the influence of risk factors on the outcome of the grafts in different recipients. METHODS: We retrospectively analyzed 88 kidneys from 44 donors that were implanted in 88 recipients at our institution between 2007-2016. We defined unsatisfactory outcome as glomerular filtration rate <30 mL/min/1.73 m2 allograft loss or recipient death within the first year after transplantation. Fifty-three kidneys were allocated and age-matched to donors above the age of 65 years (via Eurotransplant Senior Program or center offer). We compared kidney pairs with satisfactory outcome in both recipients (group A) to pairs with divergent outcome (group B) and unsatisfactory outcome in both recipients (group C). RESULTS: Thirty-four grafts (17 donors) had a satisfactory outcome for both recipients (group A), and 16 grafts (8 donors) had an unsatisfactory outcome for both recipients (group C). Donor age was significantly higher in group C vs group A (67.5 ± 6.7 vs 56.4 ± 16.0 years, P = .010). The 19 donors donating 1 kidney with satisfactory and the other with unsatisfactory outcome were 67.4 ± 10.7 years old (group B). A severe surgical complication occurred more often in recipients with an unsatisfactory outcome in comparison to patients with a satisfactory outcome. CONCLUSION: Donor age is an important risk factor for an unsatisfactory outcome, either in one or both kidneys of the same donor.

Fewer cytomegalovirus complications after kidney transplantation by de novo use of mTOR inhibitors in comparison to mycophenolic acid.

BACKGROUND: Cytomegalovirus (CMV) is a risk factor for patient and graft survival after kidney transplantation. METHODS: We retrospectively analyzed risk factors for CMV infection in 348 patients who received a kidney transplant donated after brain death (n = 232) or by living donation (n = 116) between 2008 and 2013. Of the 348 patients analyzed, 91 received a mammalian target of rapamycin inhibitor (mTORi)-based immunosuppressive regimen. A total of 266 patients were treated with standard immunosuppression (Group 1) consisting of basiliximab induction, calcineurin inhibitor (CNI), and either mycophenolic acid (MPA, n = 219) or everolimus (EVE) (n = 47). We also included 82 patients who received more intense immunosuppression (Group 2) with lymphocyte depletion, CNI, plus either MPA (n = 38) or EVE (n = 44). Only patients in the high-risk constellation received CMV prophylaxis in Group 1, while all patients in Group 2 received prophylaxis for 6 month. RESULTS: The overall rate of CMV infections was low with 10.1% in all patients. Despite the different prophylaxis strategies applied, no difference was seen in CMV infections between Group 1 (10.9%) and Group 2 (13.6%). A multivariate analysis revealed that patients on EVE had fewer CMV complications compared with patients on MPA (P = 0.013, odds ratio [OR] 4.8, confidence interval [CI] 1.4-16.5). Donor and recipient age >65 years was an independent risk factor (P = 0.002, OR 3.2, CI 1.5-6.7) for CMV infections. Patients with CMV infections had significantly worse graft function after 2 years (P = 0.001). CONCLUSION: CMV is a significant risk factor for long-term graft outcome. Patients treated with EVE developed fewer CMV complications compared to patients on MPA. The use of mTORi is useful in patients at high risk of developing CMV infections.

Ambulatory long-term pH monitoring in pigs.

BACKGROUND: pH monitoring has been established as the "gold standard" in the diagnosis of gastroesophageal reflux. Evaluation of experimental antireflux therapy should therefore also include this technique, but a suitable technique in an experimental model did not exist so far. The aim of our study was to establish a reliable method for the evaluation of an experimental reflux model in pigs. METHODS: A total of 33 German Landrace pigs with an average body weight of 56 (50.2-67.2) kg were included. pH monitoring was performed before and after open cardiomyotomy in each animal. All manipulations were performed under general anesthesia. After manometric localization of the gastroesophageal high-pressure zone, a standard pH probe was inserted into the pharynx through a small needle-punctured canal on the side of the animal's snout and placed under endoscopic guidance with the proximal sensor 3 cm above the lower esophageal sphincter (LES) and the distal sensor in the stomach for reference. The harness to carry the pH recorder on the animal's back consisted of a modified belly strap that enabled the animal to move around without limitation. For analysis the same threshold levels were defined as in humans. Gastroesophageal reflux was induced by cardiomyotomy. RESULTS: The placement of the standard pH probe was possible in all cases. Inserting the probe on the side of the snout left the animals free to nuzzle, which complies with the normal habits of pigs, without breaking the probes and without being compromised in their natural behavior. Repeated punctures for multiple measurements were easily feasible. We performed up to three examinations in each individual animal. Recording was performed for 48 h. A mean number of 67.3 (+/-9.7) acidic refluxes were registered. The mean number of long acidic refluxes was 3.2 (+/-0.75). For an average total time of 75.5 (+/-14.3) min the pH was below 4 accounting for a fraction time pH below 4 of 3.5% (+/-0.68%). Following cardiomyotomy the number of acidic refluxes increased significantly to 166.1 (+/-21.8) and the number of long refluxes to 17.74 (+/-3.35). The total time of pH below 4 increased to 371.3 (+/-62) min so that the fraction time pH below 4 was 14.5% ( p = 0.0006). CONCLUSION: pH monitoring should be mandatory in any investigation of antireflux therapy. Our method is easy and secure to perform. It is suitable for other gastrointestinal investigations (Bilitec, long-term manometry) that could be carried out using the same technique. The described data represent the basis for other investigations of experimental antireflux therapy.

Is there still a need for living-related liver transplantation in children?

OBJECTIVE: To assess and compare the value of split-liver transplantation (SLT) and living-related liver transplantation (LRT). SUMMARY BACKGROUND DATA: The concept of SLT results from the development of reduced-size transplantation. A further development of SLT, the in situ split technique, is derived from LRT, which itself marks the optimized outcome in terms of postoperative graft function and survival. The combination of SLT and LRT has abolished deaths on the waiting list, thus raising the question whether living donor liver transplantation is still necessary. METHODS: Outcomes and postoperative liver function of 43 primary LRT patients were compared with those of 49 primary SLT patients (14 ex situ, 35 in situ) with known graft weight performed between April 1996 and December 2000. Survival rates were analyzed using the Kaplan-Meier method. RESULTS: After a median follow-up of 35 months, actual patient survival rates were 82% in the SLT group and 88% in the LRT group. Actual graft survival rates were 76% and 81%, respectively. The incidence of primary nonfunction was 12% in the SLT group and 2.3% in the LRT group. Liver function parameters (prothrombin time, factor V, bilirubin clearance) and surgical complication rates did not differ significantly. In the SLT group, mean cold ischemic time was longer than in the LRT group. Serum values of alanine aminotransferase during the first postoperative week were significantly higher in the SLT group. In the LRT group, there were more grafts with signs of fatty degeneration than in the SLT group. CONCLUSIONS: The short- and long-term outcomes after LRT and SLT did not differ significantly. To avoid the risk for the donor in LRT, SLT represents the first-line therapy in pediatric liver transplantation in countries where cadaveric organs are available. LRT provides a solution for urgent cases in which a cadaveric graft cannot be found in time or if the choice of the optimal time point for transplantation is vital.

Generation of multiple angiogenesis inhibitors by human pancreatic cancer.

A primary inoculum of human pancreatic cancer cells (BxPC-3) has the ability to inhibit the growth of a secondary tumor in an in vivo animal model. Such ability suggests that the primary tumor is producing inhibitors that act at the site of the secondary tumor. Accordingly we attempted to discover which inhibitors are produced by pancreatic cancer cells. We determined that pancreatic cancer cells process angiostatin isoforms from plasminogen. Additionally, we isolated and characterized an uncleaved "latent" antiangiogenic antithrombin (aaAT) molecule processed from systemically available AT by pancreatic cancer cells as well as a cleaved form of aaAT processed from systemically available AT by pancreatic cancer cells. Human AT, cleaved with human neutrophil elastase, inhibits angiogenesis in the chorioallantoic membrane assay. This human aaAT molecule is able to inhibit the growth of pancreatic tumors in immune-compromised mice. Our work represents the first demonstration of multiple angiogenesis inhibitors from a single tumor and suggests that antiangiogenic therapies may provide an avenue for future treatment of pancreatic cancer.

Heterogeneity of angiogenic activity in a human liposarcoma: a proposed mechanism for "no take" of human tumors in mice.

BACKGROUND: Tumor cells are known to be heterogeneous with respect to their metastatic activity, proliferation rate, and activity of several enzymes. However, little is known about the heterogeneity of tumor angiogenic activity. We investigated whether heterogeneity of angiogenic activity could be responsible for the well-known observation of "no take" of human tumors transplanted into immunodeficient mice. METHODS: Severe combined immunodeficient (SCID) mice were xenotransplanted subcutaneously with tumor tissue (n = 55) or cell suspension of a human liposarcoma cell line (SW-872) or subclones (n = 28), with varying cell proliferation rates. Xenograft tumor growth was recorded for up to 6 months. Tumor tissues were then removed and analyzed for tumor cell apoptosis, microvessel density, and cell proliferation. All statistical tests were two-sided. RESULTS: Pieces of tumor derived from the parental cell line or its clones gave rise to three kinds of tumors: 1) highly angiogenic and fast-growing (aggressive) tumors, 2) weakly angiogenic and slow-growing tumors, and 3) nonangiogenic and stable tumors. Most tumors retained the original phenotype of their parental tumor. Tumor volume correlated positively with microvessel density (Spearman correlation coefficient [r] =.89; P< or =.0001) and inversely with tumor cell apoptosis (Spearman r = -.68; P =.002). Tumor volume was less strongly but still positively correlated with tumor cell proliferation in vivo (Spearman r =.55; P =.02). CONCLUSIONS: Human liposarcoma cells appear to be heterogeneous in their angiogenic activity. When tumor cells with little or no angiogenic activity are transplanted into SCID mice, a microscopic, dormant tumor results that may not grow further. Because such tiny tumors are neither grossly visible nor palpable, they have previously been called "no take." The finding that an angiogenic tumor can contain subpopulations of tumor cells with little or no angiogenic activity may provide a novel mechanism for dormant micrometastases, late recurrence, and changes in rate of tumor progression.

Effect of antiangiogenic therapy on slowly growing, poorly vascularized tumors in mice.

BACKGROUND: Angiogenesis is essential for tumor growth and progression. Therefore, inhibition of angiogenesis is being studied as a new anticancer therapy. Because cytotoxic chemotherapy is more effective on rapidly growing tumors than on slowly growing tumors, it has been assumed that antiangiogenic therapy will also be effective only on rapidly growing, highly vascularized tumors. We compared the effects of two angiogenesis inhibitors, TNP-470 and angiostatin, on slowly growing, poorly vascularized and rapidly growing, highly vascularized human tumors in mice. METHODS: Slowly growing (RT-4) and rapidly growing (MGH-U1) human bladder carcinoma cell lines were grown in severe combined immunodeficiency mice. Established tumors were treated with one of the two angiogenesis inhibitors. Tumor volumes, vascularity, and proliferation indices were determined. The in vitro effects of TNP-470 and of angiostatin on the proliferation of RT-4 and MGH-U1 cells were also investigated. All statistical tests were two-sided. RESULTS: RT-4 and MGH-U1 tumor growth was statistically significantly inhibited by both angiogenesis inhibitors (P<.001). Both inhibitors decreased the blood vessel density in both tumor types but did not alter the in vivo proliferation indices of the tumors. TNP-470, but not angiostatin, marginally decreased the in vitro proliferation of MGH-U1 cells. CONCLUSION: Slowly growing, poorly vascularized tumors in animal models respond as well as rapidly growing, highly vascularized tumors to therapy with the angiogenesis inhibitors TNP-470 and angiostatin.

Efficacy of antiangiogenic therapy with TNP-470 in superficial and invasive bladder cancer models in mice.

OBJECTIVES: To evaluate the efficacy of antiangiogenic therapy with O-(chloracetyl-carbamoyl) fumagillol (TNP-470) in a superficial and an invasive bladder cancer model in mice. The control of recurrent superficial and metastatic bladder cancer constitutes a major problem in urologic practice. Although the established therapies for these cases (immunotherapy, chemotherapy, and radiation therapy) have improved during the previous decades, further improvement and the reduction of existing side effects are needed. The inhibition of angiogenesis represents a new concept in cancer therapy. METHODS: We evaluated the in vitro effect of TNP-470 on the proliferation of bovine capillary endothelial cells (BCE), the superficial transitional cell carcinoma (TCC) cell line (KK-47), and the invasive TCC cell line (MGH-U1). To evaluate the in vivo effect of TNP-470 on the growth of advanced TCCs, both cell lines were injected subcutaneously into SCID mice. When tumors grew to a size of 100 to 200 mm(3), therapy either with TNP-470 or phosphate-buffered saline was initiated. RESULTS: TNP-470 strongly inhibited endothelial cell proliferation in vitro. The in vitro proliferation of both bladder carcinoma cell lines was also inhibited by TNP-470. However, the doses inhibitory to bladder carcinoma cells were 100-fold higher than the doses that were effective in the inhibition of endothelial cell proliferation. In vivo, TNP-470 significantly inhibited the growth of advanced KK-47 (67%) and MGH-U1 (68%) tumors in SCID mice. CONCLUSIONS: Our results indicate that antiangiogenic therapy with TNP-470 is equally effective in advanced superficial and invasive bladder carcinoma models in mice. When our results are taken together with the reports of other laboratories, TNP-470 appears to be a promising candidate as a tumor suppressor in superficial and invasive bladder cancer.

Toxic megacolon caused by cytomegalovirus colitis in a multiply injured patient.

Cytomegalovirus (CMV) colitis is a rare event that has been described mainly in immunocompromised patients with immunosuppressive medication or HIV infection. An association with severe trauma has not been described previously. We report a formerly healthy, multiply injured 75-year-old male who subsequently developed what appeared to be pseudomembranous colitis. By the time the diagnosis of toxic megacolon on the basis of CMV colitis was established, he had succumbed to multiple organ failure. Whenever pseudomembranous colitis is clinically suspected but not confirmed in a critically ill formerly healthy patient, CMV colitis should be excluded. Once the diagnosis is confirmed, generous resection of all affected colon is mandatory in view of the limited benefit of antiviral therapy in CMV-induced toxic megacolon.