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Selected AbstractsSediment production in large gullies of the Mediterranean area (NE Spain) from high-resolution digital elevation models and geographical information systems analysisEARTH SURFACE PROCESSES AND LANDFORMS, Issue 5 2003J. A. Martínez-Casasnovas Abstract Recent studies in the Mediterranean area have shown gully erosion to have a very significant contribution to total soil loss. In the Penedès vineyard region (NE Spain), between 15 and 27% of the land is affected by large gullies and gully-wall retreat seems to be an ongoing process. Multi-date digital elevation model (DEM) analysis has allowed computation of sediment production by gully erosion, showing that the sediment production rates are very high by the, up-to-date, usual global standards. Here, we present a study carried out using large-scale multi-date (1975 and 1995) aerial photographs (1 : 5000 and 1 : 7000) to monitor sediment yield caused by large gullies in the Penedès region (NE Spain). High-resolution DEMs (1 m grid) were derived and analysed by means of geographical information systems techniques to determine the gully erosion rates. Rainfall characteristics within the same study period were also analysed in order to correlate with the soil loss produced. Mass movement was the main process contributing to total sediment production. This process could have been favoured by rainfalls recorded during the period: 58% of the events were of an erosive character and showed high kinetic energy and erosivity. A sediment production rate of 846 ± 40 Mg ha,1 year,1, a sediment deposition rate of 270 ± 18 Mg ha,1 year,1 and a sediment delivery ratio of 68·1% were computed for a gully area of 0·10 km2. The average net erosion within the study period (1975,95) was 576 ± 58 Mg ha,1 year,1. In comparison with other methods, the proposed method also includes sediment produced by processes other than only overland flow, i.e. downcutting, headcutting, and mass movements and bank erosion. Copyright © 2003 John Wiley & Sons, Ltd. [source] Hepatorenal syndrome: A proposal for kidney after liver transplantation (KALT)LIVER TRANSPLANTATION, Issue 6 2007Richard Ruiz Hepatorenal syndrome (HRS) is a well-recognized complication of end-stage liver disease. Once thought to be a reversible condition with liver transplantation (LT) alone, HRS may directly contribute to the requirement for long-term dialysis posttransplant. As a result, discussion has now focused on whether or when a kidney allograft should be considered for these patients. Using the International Ascites Club guidelines with a pretransplant serum creatinine (SCr) >2.0 mg/dL to define HRS, 130 patients undergoing LT over a 10-yr period were identified, for an overall incidence of 9%. Patient survival rates at 1, 3, and 5 yr were 74%, and 68%, and 62%, respectively. Survival was significantly worse when compared to non-HRS patients undergoing LT over the same study period (P = 0.0001). For patients presenting with type 2 HRS, 7 patients (6%) developed irreversible kidney failure posttransplant compared to 0.34% in the non-HRS population (P < 0.0001). Five of these patients died within 1 yr with a median survival time of 139 days. Combined liver and kidney transplantation (CLKT) for patients with HRS is not recommended. However, an improvement in outcome can be accomplished by addressing those patients who require dialysis greater than 60 days posttransplant. We propose a role for kidney after liver transplantation (KALT) in select HRS patients. Liver Transpl 13:838,843, 2007. © 2007 AASLD. [source] Live donor liver transplantation for fulminant hepatic failure in childrenLIVER TRANSPLANTATION, Issue 11 2003Chi-Leung Liu The mortality rate among children with fulminant hepatic failure (FHF) on the waiting list for cadaveric donor liver transplantation (CDLT) is high. Results of emergency CDLT in this situation often are unsatisfactory, and a long-term survival rate less than 30% has been reported. Live donor liver transplantation (LDLT) for FHF in children has been advocated, but is reported rarely. We present our experience with LDLT in children with FHF. Between September 1993 and December 2002, primary LDLT was performed for 26 children; 8 of these children had FHF. Patient demographics, clinical and laboratory data, surgical details, complications, and graft and patient survival are reviewed. Four boys and four girls received left-lateral segment (n = 7) and full left-lobe (n = 1) grafts. Mean age was 2.9 ± 1.2 years (range, 3 months to 11 years). Causes of FHF were drug induced in 2 patients and idiopathic in 6 patients. One child received a blood group-incompatible graft. Two patients died; 1 patient of cytomegalovirus infection at 8.6 months and 1 patient of recurrent hepatitis of unknown cause at 2.8 months after LDLT. The child who received a mismatched graft had refractory rejection and underwent a second LDLT with a blood group-compatible graft 19 days afterward. He eventually died of lymphoproliferative disease. Another patient developed graft failure related to venous outflow obstruction and survived after retransplantation with a cadaveric graft. With a median follow-up of 13.2 months (range, 2.8 to 60.3 months), actuarial graft and patient survival rates were 50% and 62.5%, respectively. Survival results appear inferior compared with those of 18 children who underwent LDLT for elective conditions during the same study period (graft survival, 89%; P = .051; patient survival, 89%; P = .281). Although survival outcomes are inferior to those in elective situations, LDLT is a timely and lifesaving procedure for children with FHF. [source] Gastric contents in pediatric patients following bone marrow transplantationPEDIATRIC ANESTHESIA, Issue 7 2010GHASSAN WAHBEH MD Summary Background:, Graft versus host disease (GVHD) of the gut is thought to delay gastric emptying and so may increase the risk of aspirating retained contents while under anesthesia. Knowing that gastric emptying is delayed in patients with GVHD might lead one to choose to intubate the trachea for all patients with suspected GVHD, who present for diagnostic esophagogastricduodenoscopy (EGD). We are not aware of published data that gives specific guidance as to the need for intubation in the pediatric bone marrow or stem cell transplantation (BMT) population. This review was intended to evaluate the gastric contents (pH and volume) in this group of patients, to provide anesthesiologists with data that would inform their decisions about airway management for these patients. Methods:, Retrospective chart review of patients ,19 years of age undergoing EGD between 2004 and 2006. Gastric content volume and pH were measured in addition to underlying disease state and treatment. We compared BMT patients with suspected GVHD to nontransplant patients with other underlying gastrointestinal conditions. Results:, Data were obtained for 77 patients post-BMT undergoing EGD, including 40 patients whose biopsies and endoscopic findings were positive for GVHD, and 37 patients with no demonstrable GVHD. Records of 144 non-BMT patients undergoing EGD within the same study period were also reviewed. Conclusion:, Patients in the BMT group overall did not have higher volumes when compared to non-BMT patients. A secondary comparison of BMT patients who were found to have GVHD vs BMT patients without GVHD suggests that gastric content volume may be elevated with GVHD. Patients in the BMT group had statistically significantly higher gastric pH than patients in the non-BMT group. It is possible that the higher gastric volume in the GVHD-positive group could put them at slightly higher risk for aspiration, but the severity of any pneumonitis, should aspiration occur, might be mitigated, by the tendency toward a higher gastric pH in the BMT patients. [source] Technical Aspects of Unilateral Dual Kidney Transplantation from Expanded Criteria Donors: Experience of 100 PatientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2010B. Ekser One option for using organs from donors with a suboptimal nephron mass, e.g. expanded criteria donors (ECD) kidneys, is dual kidney transplantation (DKT). In adult recipients, DKT can be carried out by several techniques, but the unilateral placement of both kidneys (UDKT) offers the advantages of single surgical access and shorter operating time. One hundred UDKT were performed using kidneys from ECD donors with a mean age of 72 years (Group 1). The technique consists of transplanting both kidneys extraperitoneally in the same iliac fossa. The results were compared with a cohort of single kidney transplants (SKT) performed with the same selection criteria in the same study period (Group 2, n = 73). Ninety-five percent of UDKTs were positioned in the right iliac fossa, lengthening the right renal vein with an inferior vena cava patch. In 69% of cases, all anastomoses were to the external iliac vessels end-to-side. Surgical complications were comparable in both groups. At 3-year follow-up, patient and graft survival rates were 95.6 and 90.9% in Group 1, respectively. UDKT can be carried out with comparable surgical complication rates as SKT, leaving the contralateral iliac fossa untouched and giving elderly recipients a better chance of receiving a transplant, with optimal results up to 3-years follow-up. [source] Evaluation of DRAINMOD-S for simulating water table management under semi-arid conditions,IRRIGATION AND DRAINAGE, Issue 3 2002M. A. S. Wahba modèl e dela direction dela table d'eau souterraine; le drainage conventionnel; le drainage contrôlé Abstract The water table management simulation model, DRAINMOD-S, was evaluated under semi-arid conditions using field data from the Maruit experimental field in the western delta of Egypt for three cropping seasons; maize 1999, wheat 1999/2000 and maize 2000. Two water table management systems (conventional drainage (FD) and controlled drainage (CD)) were applied in the study area. The recorded data included daily ground water table depths, drain outflows during flow events, soil salinity to depth of 1.20 m from the soil surface (0.30 m interval), and relative crop yield. DRAINMOD-S was run to simulate the applied water table management systems for the same study periods. The reliability of the model was evaluated by comparing measured and predicted values of the daily ground water table depth, cumulative outflow based on total monthly outflow, soil salinity during each season, and relative crop yield. Good agreement was found between the measured and predicted values. DRAINMOD-S predicted values within an absolute deviation ranged from 11.0 to 16.0 cm for ground water table depth, from 18 to 75 mm for drain outflows, from 0.22 to 1.08 dS m,1 for soil salinity, and from 4.62 to 4.86% for relative crop yield. The model showed the potential for long-term simulation and planning of ground water table management systems under semi-arid conditions of the western delta of Egypt. Copyright © 2002 John Wiley & Sons, Ltd. RÉSUMÉ Le modèle DRAINMOD-S pour simuler la direction de la table d'eau sous des conditions demi-arides á été évalué en utilisant le data des champs experimentaux du Mariut delta denileouest d'Égypte pendant trois saisons agricoles: le maïs 1999, le blé 1999/2000 et le maïs 2000. Deux systèmes de direction de la table d'eau (drainage conventionnel (FD) et drainage contrôlé (CD)) ontété appliqués àla superficie de l'étude. Le data qui s'est remis en ordre s'inclut les mesures des profondeurs de la table d'eau souterraine, les écoulements des drains pendant les évènements de l'écoulement, la salinité du sol au profondeur de 1.20 m souterrain aux intervalles de 30 cm, etles produits agricoles relatifs. DRAINMOD-S S'est mis en courant pour simuler l'application des systèmes de la direction pour la même période d'étude. La véracité du modèle aété évaluée en comparant les valeurs mésurées avec lcelles des produits agricoles sur le profondeur de la table d'eau quotidien, l'écoulement cumulatif basé sur l'écoulement total du mois, la salinité du sol pendant chaque saison, et les produits agricoles relatifs. On a trouvé un bon accord entre les valeurs mésurées et celles qu'on avait prédites avec une déviation absolue qui rangeait de 11.0 à 16.0 cm pour la profondeur de la table d'eau, de 18 à 75 mm pour l'écoulement du drains, et de 0.22 à 1.08 dS m,1, pour la salinité du sol et de 4.62 à 4.86% pour les produits agricoles relatifs. Le modèle a indiqué une éfficacité pour une simulation allongée et pour projeter les systèmes de la direction dela table d'eau souterraine auprès les conditions demi-arides du delta ouest en Egypte. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||