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Background Ischemia-reperfusion injury (IRI) of the liver is a well-known cause of morbidity and mortality after liver transplantation. Effective treatment strategies aimed at decreasing hepatic IRI injury and accelerating liver regeneration could offer major benefits in liver transplantation, especially in the case of partial allografts. Human adipose–derived mesenchymal stem cells (HADMSCs) are an attractive source for regenerative medicine because of their anti-inflammatory and regenerative properties. We hypothesized that HADMSCs attenuate IRI and promote liver regeneration. Methods Mice were subjected to 60 minutes of partial IRI with or without 70% partial hepatectomy. Animals were treated with HADMSCs. Liver IRI was evaluated with serum levels of alanine aminotransferase, serum interleukin-6, and histopathology. Liver samples were stained for specific markers of liver regeneration. Results Histology, serum interleukin-6, and alanine aminotransferase release revealed that treatment with HADMSCs attenuated liver injury compared with control patients. Improved animal survival and increased number of regenerating cells were observed in HADMSC-treated animals who underwent IRI and partial hepatectomy compared with the control group. Conclusion HADMSC represents a potential therapeutic strategy to decrease IRI and promote regeneration in liver transplantation.

The present review discusses strategies for minimizing the ischemia/reperfusion injury (IRI) experienced during liver surgery and transplantation. We present the experimental models used to study the complexity of hepatic IRI and new surgical and pharmacologic strategies for manipulating and improving liver function after liver surgery and transplantation. This would be of clinical interest to reduce the prevalence of IRI and improve patient management and outcomes. The ongoing effort to expand the pool of usable liver grafts has made it clear that a better understanding of the mechanisms of IRI and other consequences of using expanded criteria donor (ECD) liver allografts are critical to improving results with these grafts.

Structural and mechanical properties of main YCu2 and YZn2 binary compounds with C14, C15 Laves phases and CeCu2 structure in Cu–Y–Zn alloy are investigated by first-principles calculations. The related total energies versus occupations of nonequivalent lattice sites in all four structural forms were studied. Density functional theory is considered within framework of both pseudo-potentials and plane waves basis using VASP (Vienna ab initio Software Package). Formation heat has been computed and showed that the CeCu2–YCu2 and YZn2 Laves phases have the strongest alloying ability and structural stability. Mechanical properties were calculated, discussed, and analyzed with data mining approach in terms of structure stability.

General surgery has become increasingly fragmented into subspecialties and diseases previously treated by general surgeons are now managed by "specialists". The Resident Education Committee of the Society for Surgery of the Alimentary Tract (SSAT) has reviewed the history of surgical training and factors that have contributed to this evolution to subsepcialization. As it is unlikely that this paradigm shift is reversible, a clear understanding of the contributing factors is essential. Herein, we present a timeline and taxonomy of forces in this evolution to subspecialization.

Vascular complications by compromising the blood flow to the allograft can have significant and sometimes life-threating consequences for the patient. High level of suspicion and aggressive utilization of diagnostic modalities can lead to early diagnosis and salvage of the allograft. This review will summarize the current trends in the management of vascular complications after liver transplantation. Current trends show an increase in the utilization of endovascular interventions initially to address vascular complications after liver transplantation. Operative repair still has its major role, especially if endovascular procedures fail.

Type 1 primary hyperoxaluria (PH1) causes renal failure, for which isolated kidney transplantation (KT) is usually unsuccessful treatment due to early oxalate stone recurrence. Although hepatectomy and liver transplantation (LT) corrects PH1 enzymatic defect, simultaneous auxiliary partial liver transplantation (APLT) and KT have been suggested as an alternative approach. APLT advantages include preservation of the donor pool and retention of native liver function in the event of liver graft loss. However, APLT relative mass may be inadequate to correct the defect. We here report the first case of native portal vein embolization (PVE) to increase APLT to native liver mass ratio (APLT/NLM-R). Following initial combined APLT-KT, both allografts functioned well, but oxalate plasma levels did not normalize. We postulated the inadequate APLT/NLM-R could be corrected by trans-hepatic native PVE. The resulting increased APLT/NLM-R decreased serum oxalate to normal levels within 1 month following PVE. We conclude that persistently elevated oxalate levels after combined APLT-KT for PH1 treatment, results from inadequate relative functional capacity. This can be reversed by partial native PVE to decrease portal flow to the native liver. This approach might be applicable to other scenarios where partial grafts have been transplanted to replace native liver function.

Purpose: Ureteroneocystostomy (UCN) is the most widely used urinary reconstruction technique during kidney transplantation. Disadvantages of this technique include a high incidence of hematuria and reflux, plus the potential for obstruction resulting from distal ureteral fibrosis. Pyeloureterostomy (PU) avoids these complications but increases the technical complexity. Methods: Between January 1990 and December 2005, 1066 adults patients underwent kidney transplantations; 768 patients (72.1%) had urinary reconstruction by PU and 298 (27.9%) underwent UNC. Results: Patients in the PU group underwent simultaneous ipsilateral native nephrectomy. The operative time was longer in the PU group compared with the UNC group: 210 � 36 min versus 182 � 24 min (P < 0.001). Overall surgical complications in the PU group were comparable to those in the UNC group (9.5% versus 12.3%). The urinary complication rate was also comparable in both groups: 3.2% (25 of 768) in the PU group and 5% (15 of 298) in the UNC group. However, urinary obstruction comprised 60% of urinary complications in the UNC group, compared with 32% in the PU group (P < 0.01). We treated most urinary complications non-operatively. However, 24% of patients (six of 25) in the PU group needed operative intervention or revision for ureteral reconstruction, compared with 46.6% (seven of 15) in the UNC group (P < 0.01). Conclusions: Pyeloureterostomy is a safe and effective method for urinary tract reconstruction in renal transplantation. Pyeloureterostomy should be part of every transplant surgeon’s armamentarium.

This study aims to evaluate the fluorescence property of wool fabric dyed with indicaxanthin, natural dye. Fluorescence measurements have been developed on wool samples before and after dyeing. The emission spectrum of the undyed wool fabric does not illustrate any peak and in the contrary, dyed wool sample present interesting photoluminescence property and the highest value was recorded at 576 nm. Aging behavior upon exposure to light irradiation and upon washing was studied and it has been proved that samples keep interesting fluorescence properties.

Background Organ shortage is the greatest challenge facing the field of organ transplantation today. Use of more organs of marginal quality has been advocated to address the shortage. Method We examined the pattern of donation and organ use in the United States as shown in the Organ Procurement and Transplantation Network/United Network for Organ Sharing database of individuals who were consented for and progressed to organ donation between January 2001 and December 2010. Results There were 66,421 living donors and 73,359 deceased donors, including 67,583 (92.1 %) identified as donation after brain death and 5,776 (7.9 %) as donation after circulatory death (DCD).Comparing two periods, era 1 (01/2001-12/2005) and era 2 (01/2006-12/2010), the number of deceased donors increased by 20.3 %from33,300 to 40,059while there was a trend for decreasing living donation. The DCD subgroup increased from 4.9 to 11.7 % comparing the two eras. A significant increase in cardiovascular/cerebrovascular disease as a cause of deathwas also noted, from38.1 %in era 1 to 56.1 %in era 2 (p

Background: Using SRTR/UNOS data, it has previously been shown that increased liver transplant centre volume improves graft and patient survival. In the current era of health care reform and pay for performance, the effects of centre volume on quality, utilization and cost are unknown. Methods: Using the UHC database (2009-2010), 63 liver transplant centres were identified that were organized into tertiles based on annual centre case volume and stratified by severity of illness (SOI). Utilization endpoints included hospital and intensive care unit (ICU) length of stay (LOS), cost and in-hospital mortality. Results: In all, 5130 transplants were identified. Mortality was improved at high volume centres (HVC) vs. low volume centres (LVC), 2.9 vs. 3.4%, respectively. HVC had a lower median LOS than LVC (9 vs. 10 days, P < 0.0001), shorter median ICU stay than LVC and medium volume centres (MVC) (2 vs. 3 and 3 days, respectively, P < 0.0001) and lower direct costs than LVC and MVC ($90 946 vs. $98 055 and $101 014, respectively, P < 0.0001); this effect persisted when adjusted for severity of illness. Conclusions: This UHC-based cohort shows that increased centre volume results in improved long-term post-liver transplant outcomes and more efficient use of hospital resources thereby lowering the cost. A better understanding of these mechanisms can lead to informed decisions and optimization of the pay for performance model in liver transplantation. © 2012 International Hepato-Pancreato-Biliary Association.

BackgroundA growth in the utilization of high-risk allografts is reflective of a critical national shortage and the increasing waiting list mortality. Using risk-adjusted models, the aim of the present study was to determine whether a volume–outcome relationship existed among liver transplants at high risk for allograft failure.MethodsFrom 2002 to 2008, the Scientific Registry of Transplant Recipients (SRTR) database for all adult deceased donor liver transplants (n= 31587) was queried. Transplant centres (n= 102) were categorized by volume into tertiles: low (LVC; 31 cases/year), medium (MVC: 64 cases/year) and high (HVC: 102 cases/year). Donor risk comparison groups were stratified by quartiles of the Donor Risk Index (DRI) spectrum: low risk (DRI ≤ 1.63), moderate risk (1.64 > DRI > 1.90), high risk (1.91 > DRI > 2.26) and very high risk (DRI ≥ 2.27).ResultsHVC more frequently used higher-risk livers (median DRI: LVC: 1.82, MVC: 1.90, HVC: 1.97; P < 0.0001) and achieved better risk adjusted allograft survival outcomes compared with LVC (HR: 0.90, 95%CI: 0.85–0.95). For high and very high risk groups, transplantation at a HVC did contribute to improved graft survival [high risk: hazard ratio (HR): 0.85, 95% confidence interval (CI): 0.76–0.96; Very High Risk: HR: 0.88, 95%CI: 0.78–0.99].ConclusionWhile DRI remains an important aspect of allograft survival prediction models, liver transplantation at a HVC appears to result in improved allograft survival with high and very high risk DRI organs compared with LVC.

La culture du geranium rosat, plante aromatique et medicinale, ouvre de nouvelles perspectives dans differents secteurs economiques via la valorisation de son huile essentielle (HE) avec des retombees economiques directes pour notre pays (Algerie). Neanmoins, cette culture a connu une courbe descendante ces dernieres annees, et les raisons de cet effritement sont multiples et variees. La presente etude, une revue de litterature, fait le point sur les differentes etapes qu’a connues l’exploitation industrielle de cette plante a parfum. Aussi, elle met en exergue l’importance de son HE sur le plan economique et therapeutique, mais surtout elle se veut un plaidoyer pour ressusciter et booster la culture et la transformation du geranium rosat pour un interet aussi bien ethnobotanique que pharmaceutique. Le marche des HE en Algerie est un secteur florissant. Il s’agit aujourd’hui de le developper pour faire de cette activite une source supplementaire de revenu et un outil de developpement durable.

BackgroundMany patients on hemodialysis do not have adequate anatomy for native arteriovenous fistulas. In these patients, synthetic conduits remain an alternative option for permanent hemodialysis access. We sought to compare the standard cuffed expanded polytetrafluoroethylene (ePTFE) graft with the bovine carotid artery (BCA) graft.MethodsThis was a prospective, randomized controlled trial that was set in an academic medical center. We enrolled 26 patients in the BCA group and 27 patients in the ePTFE group. Primary, assisted primary, and secondary patency were calculated using the Kaplan-Meier method. Complications were monitored and are reported.ResultsAlthough there was no significant difference in secondary patency rates, primary and assisted primary patency rates were significantly higher in BCA than in the ePTFE grafts (60.5% vs 10.1% and 60.5% vs 20.8% at 1 year, respectively). The BCA graft survival advantage was most profound in the upper arm grafts with significantly higher primary and assisted patency rates (P < .0001 and .0005, respectively). The total number of interventions (upper arm grafts) and total number of angioplasties (overall and upper arm) required to maintain patency were significantly fewer in the BCA group. The most common complication was graft thrombosis which occurred 0.34 ± 0.09 times per patient year in the BCA group compared to 0.77 ± 0.16 times per patient year in the ePTFE group, P = .01.ConclusionThe BCA graft is an excellent option for patients on hemodialysis that are not suitable for native arteriovenous fistulas, as these grafts required fewer interventions than the ePTFE grafts to maintain patency.

Numerous reports have documented reduced graft and patient survival after use of hepatitis C (HCV) seropositive allografts in liver transplantation (OLT). We aimed to examine if the use of a HCV+ liver allograft affects patient and graft survivals compared to HCV− donor allografts in a case-controlled analysis of the united network for organ sharing (UNOS) database. We examined 63,149 liver transplants (61,905 donors HCV−; 1,244 donors HCV+) from the UNOS standard transplant analysis and research (STAR) file from 1987 to 2007. Donor and recipient demographics and outcomes were collected in which donor HCV serology was complete. A case-controlled cohort from 11 donor and recipient variables comparing donor HCV− and HCV+ allografts (n = 540 in each group) was created using propensity scores with a matching algorithm. Graft and patient survival was estimated using Kaplan–Meier survival curves. Significant differences were evident in the unadjusted cohort between recipients who received HCV+ and HCV− allografts, including HCV+ recipients, donor and recipient age, and model for end-stage liver disease (MELD) exception cases. Use of HCV+ allograft resulted in significantly lower graft survival (8.1 vs. 10.6 years; P = 0.001) and patient survival (10.2 vs. 12.3 years; P = 0.01) after OLT. In the matched cohort, HCV seropositivity had no detrimental effect on the graft (P = 0.57) or patient (P = 0.78) survival after OLT. This is the first population-based analysis to show that after adjusting for donor and recipient characteristics there was no difference in graft or patient survival with the use of HCV+ donor liver allografts compared to HCV− donor liver allografts.

Right lobe donor hepatectomy (RLDH) is a potential source of liver allografts given the ongoing shortage of deceased donor organs available. Since there is no live donor registry in the United States, a population-based, unsolicited state-wide analysis has yet to be reported.The New York (NY) State Inpatient Database was used to query 1,524 elective liver lobectomies performed from 2001 to 2006. RLDH were identified in this cohort (n = 195; 13%). Most common indications for elective right lobe hepatectomy (ERH) were metastatic colon cancer (50%) and hepatocellular carcinoma (HCC) (34%). Primary outcomes were mortality, perioperative resources and major postoperative complications.After a dramatic drop in 2002, there was a slow increase in RLDH from 2003 to 2006 in New York. Donors were younger (median age 36 vs. 60 years, P0.0001) and healthier (75% with no comorbidities vs. 18%, P0.0001) than patients undergoing ERH for other causes. Median length of hospital stay was 7 days in both groups. Donors were less likely to require blood transfusion (22.6 vs. 62.8%, P0.0001) and received less blood (mean 0.10 units vs. 2.4 units). Major post-operative complications based on the Clavien classification occurred in only 2.6% of donor cases compared to 13.8% in non-donors (P0.0001). There was one RLDH in-hospital mortality (0.5%) in New York compared to 4.3% after ERH (P = 0.003).This study represents one of the first unsolicited regional analyses of donor morbidity and resource utilization for RLDH and further emphasizes the need and utility of a live donor registry.

Recent United Network for Organ Sharing (UNOS) data suggest that live kidney donation is stagnant. Current practices and trends in laparoscopic donor nephrectomy (LDN) among the transplant community remain largely unknown. From the Nationwide Inpatient Sample (NIS) from 1998 to 2006, patients undergoing LDN (n = 9,437) were identified. Live kidney donation in the United States did not show an increase in the NIS. Of the live donor cases recorded, 58 (0.61%) were associated with a major short-term complication. The number of LDNs performed by transplant surgeons decreased over the study period from 76.5% in 1998 to 30.4% in 2006. In the United Stares, LDNs are performed safely with a low short-term complication rate. Despite the use of laparoscopy and the increased need of donor organs, the rate of LDN in kidney transplantation has not increased proportionally.

Schinus molle ou le faux poivrier appartient a la famille des Anacardiacea. La plupart des especes de cette famille sont caracterisees par une production importante en huile et en huile essentielle. Il a ete utilise comme epice dans de nombreux pays sud Americains grâce a ces fruits de saveurs chaude et piquante. Le faux poivrier est connu par ces proprietes astringentes, stimulantes, diuretiques, digestives, toniques et antivirales. Cette espece n'est pas utilisee en therapeutique en Algerie. Des recherches sur les bienfaits de cette plante sont toujours d'actualite, avec pour consequence de nouvelle decouverte dont les applications sont nombreuses. Dans le cadre de notre travail de recherche de nouveaux produits a caractere aromatique et/ou a activite biologique, et dans le but de valorise le cortege floristique de notre pays, nous avons entrepris un travail qui vise la caracterisation et la determination des effets antibacterien des huiles essentielles du faux poivrier les resultats sont les suivants: Les huiles essentielles de la plante (feuilles et baies) ont ete extraites par hydrodistillation. Leur rendement sont respectivement de 2,22% et de 6,33%. La determination des indices physicochimiques de ces huiles a montree que les HE des feuilles sont plus lourdes et stable que celle des baies. L'identification des principaux constituants par la GC/MS a indique que les HE du faux poivrier sont formes de 67 composes. Les composes majoritaires sont l'α-phellandrene (24,32%), limonene (21,62%), β-myrcene (17,76%) et l'α-pinene (4,13%). Les composes majoritaires des HE des baies sont l'α-phellandrene (23,28%), limonene (21,04%), 3-carene (17,35%) et l'α-pinene (3,98%). Les HE des feuilles exhibent un pouvoir antimicrobien important sur B subtilis, un pouvoir antimicrobien moyen sur S. aureus, S. epidermidis et C. albicans, un pouvoir antimicrobien faible sur E. coli et Pseudomonas sp. et aucun pouvoir antimicrobien sur Agrobacterium. La CMI des HE des feuilles pour B. subtilis, S. aureus, S. epidermidis et C. albicans est de 6,25% et celle d'E. coli et Pseudomonas sp. est de l'ordre de 50%. L'activite des HE des baies a ete moyenne sur B. subtilis et S. epidermidis, faible sur E. coli, S. aureus et C. albicans. La CMI des HE des baies pour S. epidermidis est de l'ordre de 25%, celle de B. subtilis et S. aureus est de l'ordre de 50%. La CMI de C. albicans et E. coli est de l'ordre de 100%.

This article investigates the growth of InN layers on (1 0 0) InP in ultra-high vacuum using a glow discharge source (GDS). Auger electron spectroscopy (AES) was used to understand the different steps of the nitridation process with the analysis of In-MNN, N-KLL and P-LMM transitions. A modeling of Auger signals using a stacked layers model allows us to confirm that four monolayers of indium nitride are created on (1 0 0) InP. InN layers grown on (1 0 0) InP were studied optically by photoluminescence (PL) spectroscopy versus the excitation power and the sample temperature (10–300 K). Results show broad spectral band energy close to the lowest reported InN bandgap. The temperature dependence of the PL peak energy showed a S-shaped behavior (decrease–increase–decrease). The results suggest that the InN-related emission is significantly affected by the change in carrier dynamics with increasing temperature: the effect can be due to the large exciton localization effects.

There is a paucity of data on long-term outcomes of older kidney recipients. Our aim was to compare the early and long-term outcomes of deceased donor kidney transplantation in patients agedor=60 years with outcomes in younger recipients.From 1998 to 2005, we performed 271 deceased donor kidney transplants. There were 76 recipients (28.1%)60 years old. Older candidates were carefully selected based on their physiologic, cardiac, and performance status. Demographic data, including clinical characteristics, early complications, mortality, and patient and graft survival rates, were collected and analyzed.Older patients had comparable perioperative mortality and morbidity, incidence of delayed graft function (DGF), length of stay, and readmissions compared with younger patients. The rates of acute rejection and major infections were also comparable between the 2 study groups. Among older recipients, 25/76 (32.1%) patients received extended criteria donor kidneys compared with only 35/195 (17.9%) of younger patients (P.001). Nevertheless, equivalent 1-, 3-, and 5-year allograft survival rates were observed in elderly and young patients; 91.5% versus, 92.5%, 78.5% versus 81.9%, and 75.6% versus 78.5%, respectively. Overall patient survival was also comparable in both groups.Kidney transplantation in appropriately selected elderly recipients provides equivalent outcomes compared with those observed in younger patients. These observations support the notion that older recipients should not lose access to deceased donor kidney transplantation in the effort to achieve a perceived gain in social utility.

Background. Compared with standard donors, kidneys recovered from donors after cardiac death (DCD) exhibit higher rates of delayed graft function (DGF), and DCD livers demonstrate higher rates of biliary ischemia, graft loss, and worse patient survival. Current practice limits the use of these organs based on time from donor extubation to asystole, but data to support this is incomplete. We hypothesized that donor postextubation parameters, including duration and severity of hemodynamic instability or hypoxia might be a better predictor of subsequent graft function. Methods. We performed a retrospective examination of the New England Organ Bank DCD database, concentrating on donor factors including vital signs after withdrawal of support. Results. Prolonged, severe hypotension in the postextubation period was a better predictor of subsequent organ function that time from extubation to asystole. For DCD kidneys, this manifested as a trend toward increased DGF. For DCD livers, this manifested as increased rates of poor outcomes. Maximizing the predictive value of this test in the liver cohort suggested that greater than 15 min between the time when the donor systolic blood pressure drops below 50 mm Hg and flush correlates with increased rates of diffuse biliary ischemia, graft loss, or death. Donor age also correlated with worse outcome. Conclusions. Time between profound instability and cold perfusion is a better predictor of outcome than time from extubation to asystole. If validated, this information could be used to predict DGF after DCD renal transplant and improve outcomes after DCD liver transplant.

Liver ischemia-reperfusion (I/R) injury is a well-known cause of morbidity and mortality following liver surgery and transplantation. Hepatic steatosis increases the extent of cellular injury incurred during I/R injury. We sought to identify measures that reduced the untoward sequelae of liver I/R injury.Male Zucker rats were subjected to 75 minutes of 70% hepatic ischemia, and 3 hours of reperfusion. The ischemic periods were based on the following protocols: continuous clamping (CC) for 75 minutes; intermittent clamping (IC) with five cycles of 15 minutes clamp on and 5 minutes clamp off; or ischemic preconditioning (IP) with 10 minutes clamp on, 15 minutes off, and 60 minutes on (n=7 in each group). Warm I/R injury was evaluated using serum levels of aspartate aminotransferase (AST), serum interleukin (IL)-6, as well as hematoxylin and eosin staining.Hepatocellular injury was significantly reduced with IP or IC compared with CC (AST: 3285+/-122.3 and 2875+/-285.4 compared with 5436.3+/--984.7 units/L, respectively; P.01). Serum IL-6 level was also significantly reduced with IP and IC compared with CC (70+/-8.8 and 76+/-6.2 compared with 147+/-8.5 ng/l, respectively (p.01). Histological analysis also revealed that IC and IP provided significant protection compared with the CC group.IC and IP increased the tolerance of a fatty liver to hepatic I/R injury.

Electron spectroscopy (AES and XPS) and photoluminescence analysis (PL) were used to study porous layers elaborated by electrochemical etching of p-GaAs and n-InP substrates. Surface characterizations have been performed on the as received porous substrates, ions bombarded and nitridated porous layers. Porous surfaces of GaAs(1 0 0) and InP(1 0 0) have been compared after different treatments: Argon ion bombardment and nitridation with a glow discharge source (GDS) in UHV. These processes have been followed by Auger measurements (AES). The effects of the bombardment and the nitridation of porous InP were studied. The PL investigations of the porous GaAs layer show visible and infrared photoluminescence bands. Quantum confinement in the nanocrystallites of GaAs formed by electrochemical etching can explain the luminescence of the porous GaAs layers.

Interferons (IFNs) are known to have antiproliferative and immunoregulatory activities that are modulated through specific cell surface ligands, known as IFN-alpha, -beta, and -gamma receptors. The presence of these receptors and their impact on response to adjuvant therapy in patients with pancreatic cancer has not been determined.Slides were prepared from 46 patients with pancreatic adenocarcinoma. Immunohistochemistry (IHC) was subsequently used to determine the expression of IFN- alpha/beta receptor-chain 2 (IFN-alpha/betaR) and IFN-gamma receptor-chain 1 (IFN-gammaR). The correlation between IFN receptor expression, tumor characteristics, and the overall patient response to adjuvant therapy were determined analytically.The IHC performed for pancreatic adenocarcinoma demonstrated a high IFN-alpha/betaR expression in 4% (2/46) of patients, moderate expression in 20% (9/46) of patients, and faint or no expression in 76% (35/46) of patients. IHC confirmed a high expression of IFN-gammaR in 52% (24/46) of patients, moderate expression in 35% (16/46) of patients, and faint or no expression in the remaining 13% (6/46) of patients. Thirty-two (69.7%) patients received adjuvant therapy. Clinicopathological survey did not demonstrate any significant correlation between IFN-alpha/betaR and IFN-gammaR expression with regard to tumor size, vascular invasion, perineural invasion, lymph node metastases, or stage of disease. Use of adjuvant therapy was associated with increased survival in patients with IFN-alpha/betaR-positive tumors compared with patients with IFN-alpha/betaR-negative tumors (24 months versus 14.7 months in log rank test, p=0.012). The expression of IFN-gammaR, however, had no impact on patient survival (20 months vs 17 months; p=0.656, log rank test).IFN-alpha/betaR is associated with improved survival for patients with resectable pancreatic cancer who received adjuvant therapy.

Background: There are over 250 kidney transplant programs in the USA. Objective: To determine if highly competitive regions, defined as regions with a higher number of transplant centers, will approve and wait-list more end-stage renal disease (ESRD) candidates for transplant despite consistent incidence and prevalence of ESRD nationwide. Methods: ESRD Network and OPTN data completed in 2011 were obtained from all transplant centers including listing data, market saturation, market share, organs transplanted, and ESRD prevalence. Herfindahl- Hirschman Index (HHI) was used to measure the size of firms in relation to the industry to determine the amount of competition. Results: States were separated into 3 groups (HHI1800 considered highly concentrated). The percentage of ESRD patients listed in competitive, moderate, and highly concentrated regions were 19.73%, 17.02%, and 13.75%, respectively. The ESRD listing difference between competitive versus highly concentrated was significant (p

Liver regeneration (LR) is of crucial importance to patients with acute liver failure, those undergoing live donor liver transplantations or extended liver resections. Effective treatment strategies aimed at accelerating liver regeneration could offer major benefits in these patients. Due to easy accessibility, human adipose-derived mesenchymal stem cells (HADMSC) are an attractive source for regenerative medicine. Herein, we investigated the effect of HADMSC on LR in a murine model. We hypothesized that HADMSC will promote LR.Mice were subjected to CCl4-induced acute liver failure (ALF). Animals in the experimental arm were treated with HADMSC prior to CCl4-induced ALF. Liver injury was evaluated using serum levels of alanine aminotransferase (ALT), serum interleukin-6 (IL-6), and histopathology. Liver samples were stained for a specific marker of regeneration, proliferating cell nuclear antigen (PCNA).Histology, serum IL-6, and ALT release revealed that HADMSC treatment attenuated liver injury compared with control animals. In addition, animals treated with HADMSC were observed to have improved survival and increased number of PCNA positive cells on histology when compared with controls.HADMSCs represent a potential therapeutic strategy to promote liver regeneration.

Summary Protein kinase C (PKC) isozymes are the paradigmatic effectors of lipid signaling. PKCs translocate to cell membranes and are allosterically activated upon binding of the lipid diacylglycerol to their C1A and C1B domains. The crystal structure of full-length protein kinase C βII was determined at 4.0 A, revealing the conformation of an unexpected intermediate in the activation pathway. Here, the kinase active site is accessible to substrate, yet the conformation of the active site corresponds to a low-activity state because the ATP-binding side chain of Phe629 of the conserved NFD motif is displaced. The C1B domain clamps the NFD helix in a low-activity conformation, which is reversed upon membrane binding. A low-resolution solution structure of the closed conformation of PKCβII was derived from small-angle X-ray scattering. Together, these results show how PKCβII is allosterically regulated in two steps, with the second step defining a novel protein kinase regulatory mechanism.

Obectives Interferons (IFNs) are known to have antiproliferative and immunoregulatory activities that are modulated through specific cellular-surface ligands, known as IFN-alpha, -beta, and -gamma receptors. The presence of these receptors and their impact on survival in patients with pancreatic cancer has not been determined. Methods Slides were prepared from 46 patients with pancreatic adenocarcinoma. Immunohistochemistry (IHC) was used subsequently to determine the expression of IFN-alpha/beta receptor-chain 2 (IFNalpha/betaR) and IFN-gamma receptor-chain 1 (IFNgammaR). The correlation among IFN-receptor expression, characteristics of neoplasms, and overall patient survival were determined analytically. Results The IHC performed for pancreatic adenocarcinoma demonstrated a high IFNalpha/betaR expression in 4% (2/46) of patients, moderate expression in 20% (9/46), and faint or no expression in 76% (35/46). IHC confirmed a high expression of IFNgammaR in 52% (24/46) of patients, moderate expression in 35% (16/46), and faint or no expression in the remaining 13% (6/46). A clinicopathologic survey failed to demonstrate any significant correlation between IFNalpha/betaR and IFNgammaR expression with regard to size of neoplasm, vascular or perineural invasion, lymph node metastases, or stage of disease. Kaplan-Meier survival analyses demonstrated a survival advantage in those patients whose neoplasms expressed moderate to high IFNalpha/betaR expression, compared with those with faint or no IFNalpha/betaR expression (22 vs 13 months; P = .012, log-rank test). The expression of IFNgammaR, however, had no impact on patient survival (20 months vs 17 months; P = .66, log-rank test). Conclusions The IFNalpha/betaR is an independent prognostic factor in patients with pancreatic cancer.

Optical studies of B x Ga 1− x As/GaAs epilayers grown by Metal Organic Chemical Vapor Deposition (MOCVD), with boron composition ≤ 7%, have been achieved by photoluminescence spectroscopy (PL) as a function of the excitation density and the sample temperature (10–300 K). The Raman scattering have shown a linear variation between boron composition and Raman shift of the optical phonons modes. It has shown that the BGaAs PL band shifts to low energy side when the boron composition is ≤ 2.5% compared to the GaAs one. But this band increases slowly as the boron content increases in range 2.5% to 7%. Blue shifts of the PL bands were observed when increasing the excitation density. The temperature dependence of the PL peak energy has shown an S-shaped behavior. Based on these experimental results, we have suggested that the carrier recombination mechanisms in the BGaAs epilayer result from exciton-localization like mode. These experimental results show that boron incorporation does not cause a great modification of the band structure in B x Ga 1− x As alloys compared to the pure GaAs.

Organ transplantation is not only considered as the last resort therapy but also as the treatment of choice for many patients with end-stage organ damage. Recipient-mediated acute or chronic immune response is the main challenge after transplant surgery. Nonspecific suppression of host immune system is currently the only method used to prevent organ rejection. Lifelong immunosuppression will cause significant side effects such as infections, malignancies, chronic kidney disease, hypertension and diabetes. This is more relevant in children who have a longer life expectancy so may receive longer period of immunosuppressive medications. Efforts to minimize or complete withdrawal of immunosuppression would improve the quality of life and long-term outcome of pediatric transplant recipients.

In this paper, we present an experimental study of the thermal emission and band-filling effects on the rise time in high-quality InGaAs/InAs/GaAs quantum dots emitting at 1.2 μm at 10 K. At excitation density of 104 W cm−2, the photoluminescence rise time, which is dominated by the relaxation time, of the ground and first excited states are independent of temperature (40 ps). At excitation density of 5600 W cm−2 the ground (first excited) state photoluminescence rise time varies from 90 ps (110 ps) at 10 K to 40 ps (70 ps) at 160 K. This behavior is attributed to the band-filling and the thermal emission effects on the efficiency of the relaxation.

We attempted to gain some insight into the mechanical properties of poorly consolidated granular rock by preparing and testing synthetic rock specimens in which different cement content and bimodal grain-size distributions were used. We mixed various proportions of fine and coarse sand, Portland cement, and water. The mixture was cast in a mold and left pressure-free during curing, thus ensuring that the final material was poorly consolidated. The specimens were tested in a uniaxial press. During these tests, the static Young’s modulus was measured by performing small stress excursions at discrete intervals along the stress-strain curve. We observed significant non-linear elasticity (i.e., Young’s modulus increased with stress) in all the specimens. As expected, the uniaxial compressive strength increased with increasing cement content. Furthermore, we observed a transition from grain-size sensitivity of strength at cement contents less than 20–30% to grain-size independence above this value. At high cement content, the measured values of Young’s modulus are relatively well explained by a model based on rigid inclusions embedded in a soft matrix. At low cement content, we suggest that modelling the individual cemented grain-to-grain contacts becomes necessary. But this could not be done here for lack of microstructural information.

The growth features of the nitrogen incorporation into GaAs grown by metalorganic vapour phase epitaxy (MOVPE) are presented, with a comparison between experimental results and a kinetic model. The so-called ‘distribution coefficient’ of nitrogen varies in the range 180–1000 depending essentially on growth temperature. Experimental results were analysed with a schematic process of surface reaction kinetics for controlling the mass transfer. Some kinetic rate constants are proposed. The modelling of N incorporation at 520–560°C allows an identification of species coming from the DMHy thermal decomposition. Surprisingly, this study shows that the rate of N incorporation weakly depends on the arsenic precursor at low growth temperatures.

The lipid second messenger diacylglycerol acts by binding to the C1 domains of target proteins, which translocate to cell membranes and are allosterically activated. Here we report the crystal structure at 3.2 A resolution of one such protein, beta2-chimaerin, a GTPase-activating protein for the small GTPase Rac, in its inactive conformation. The structure shows that in the inactive state, the N terminus of beta2-chimaerin protrudes into the active site of the RacGAP domain, sterically blocking Rac binding. The diacylglycerol and phospholipid membrane binding site on the C1 domain is buried by contacts with the four different regions of beta2-chimaerin: the N terminus, SH2 domain, RacGAP domain, and the linker between the SH2 and C1 domains. Phospholipid binding to the C1 domain triggers the cooperative dissociation of these interactions, allowing the N terminus to move out of the active site and thereby activating the enzyme.

Optical studies of GaAs1−xNx/GaAs and BxGa1−xAs/GaAs epilayers grown by metal organic chemical vapour deposition (MOCVD), with various nitrogen (N) and boron (B) compositions, have been achieved by photoluminescence spectroscopy (PL) as a function of the excitation density and the sample temperature (10–300 K). The experiments have shown that the GaAsN PL band emission presents a more significant red shift than the BGaAs emission. For the GaAsN a reduction of 110 meV/1%N is shown, but for the BGaAs the PL band emission shifts to the low-energy side by up to 2.5%. A more significant blue shift of the PL bands with increasing the excitation density has been observed for GaAsN compared to BGaAs epilayer structures. The temperature dependence of the PL peak energy has shown S-shaped behaviour for both structures, but the localisation effects are more important in GaAsN than in BGaAs. Based on these experimental results, it is shown that B incorporation does not cause large modification of the band structure in BxGa1−xAs alloys compared to pure GaAsN structures.

Background Early and long-term outcome of gastrectomy for gastric cancer in elderly adults has been a subject of controversy and debate. Method and methods Clinical information was reviewed for patients undergoing gastrectomy for gastric cancer during an 11-year period (1990–2000) at the University of Tennessee Medical Center at Knoxville. Patient demographics, tumor characteristics, operative mortality and morbidity, survival, and length of hospitalization were reviewed. Results Of 48 patients who underwent gastric resection for gastric adenocarcinoma, 24 were older than 70 and 24 younger than 70. There were no differences between the two groups regarding tumor characteristics, including location, tumor size, grade, gross pathology, lymph node involvement, lymphovascular invasion, and stage. In the elderly group, 75% underwent subtotal gastrectomy and 25% had total gastrectomy with or without resection of adjacent organs. In the younger patients, these numbers were 66.6% and 33.3%, respectively, which was statistically insignificant ( P = 0.5). Five-year survival was 16.6% among elderly patients compared to 20.8% in the younger patients ( P = 0.45). Half of the elderly patients and 39% of young patients had other comrobidities ( P = 0.45). Postoperative mortality and morbidity was 8.33% and 33.3% in elderly patients, compared to 4.2% and 33.3%, respectively, in the younger group. These results were statistically insignificant ( P = 0.4). The median postoperative length of stay was 15 days (95 percent confidence interval, 11–19 days) in younger patients compared to 18 days (95 percent confidence interval, 13–22 days) in the elderly group ( P = 0.3). Conclusion This study suggests that gastrectomy can be carried out safely in elderly patients. The early and long-term outcomes in elderly patients (over age 70) are comparable to younger patients (under age 70). Age alone should not preclude gastric resection in elderly patients.

Axillary dissection is the current standard of care for patients with breast cancer who are diagnosed with metastasis to axillary sentinel lymph nodes (SLNs). Recently, that concept has come under increasing scrutiny because not all women with a positive SLN will need further dissection. The purpose of this study was to look at nonsentinel lymph node status in patients with breast cancer and axillary SLN metastasis in an effort to determine tumor variables that can guide further treatment if there are additional axillary nodes involved. A retrospective chart review was performed on patients with breast cancer who underwent SLN biopsy between July 1998 and April 2003. χ2 analysis, Student t test, and multivariate analysis were used to determine the significance of tumor size, grade, location, estrogen receptor (ER) and progestrone receptor (PR) receptor status, angiolymphatic invasion, stage, and number and size of SLNs in predicting the status of nonsentinel lymph nodes. During the study interval, 116 patients were identified who underwent SLN biopsy and 34 (29.3%) had positive SLNs. All of these patients underwent complete axillary node dissection and 11 patients (32.3%) had non-SLN metastasis. The presence of palpable breast mass ( P = 0.03), tumor size ( P = 0.04), angiolymphatic invasion ( P = 0.03), and extracapsular extension of SLN metastasis ( P = 0.001) were the variables that predicted non-SLN involvement. Micrometastasis was inversely related to non-SLN involvement. In patients with breast cancer and SLN metastasis, the presence of a palpable breast mass, tumor size, angiolymphatic invasion, and extracapsular node extension increase the likelihood of identifying additional node metastasis on subsequent axillary dissection.

In order to isolate the effect of grain size and cementation on the mechanical behaviour of poorly consolidated granular rock, we prepared synthetic rock samples in which these two parameters were varied independently. Various proportions of sand, Portland cement and water were mixed and cast in a mold. The mixture was left pressure-free during curing, thus ensuring that the final material was poorly consolidated. We used two natural well-sorted sands with grain sizes of 0.22 and 0.8 mm. The samples were mechanically tested in a uniaxial press. Static Young's modulus was measured during the tests by performing small stress excursions at discrete intervals along the stress–strain curves. All the samples exhibited nonlinear elasticity, i.e., Young's modulus increased with stress. As expected, we found that the uniaxial compressive strength increased with increasing cement content. Furthermore, we observed a transition from grain size sensitivity of strength at cement content less than 20–30% to grain size independence above this value. The measured values of Young's modulus are well explained by models based on rigid inclusions embedded in a soft matrix, at high cement content, and on cemented grain-to-grain contacts, at low cement content. Both models predict grain size independence in well-sorted cemented sands. The observed grain size sensitivity at low cement content is probably due to microstructural differences between fine- and coarse-grained materials caused by small differences in grain sorting quality.

Sildenafil (Viagra) potentiates penile erection by acting as a nonhydrolyzable analog of cGMP and competing with this nucleotide for catalysis by phosphodiesterase-5 (PDE5), but the characteristics of direct binding of radiolabeled sildenafil to PDE5 have not been determined. [3H]Sildenafil binding to PDE5 was retained when filtered through nitrocellulose or glass-fiber membranes. Binding was inhibited by excess sildenafil, 2-(2-methylpyridin-4-yl)methyl-4-(3,4,5-trimethoxyphenyl)-8-(pyrimidin-2-yl)methoxy-1,2-dihydro-1-oxo-2,7-naphthyridine-3-carboxylic acid methyl ester hydrochloride (T-0156), 3-isobutyl-1-methylxanthine, EDTA, or cGMP, but not by cAMP or 5'-GMP. PDE5 was the only [3H]sildenafil binding protein detected in human lung extract. Using purified recombinant PDE5, [3H]sildenafil exchange dissociation yielded two components with t1/2 values of 1 and 14 min and corresponding calculated KD values of 12 and 0.83 nM, respectively. This implied the existence of two conformers of the PDE5 catalytic site. [3H]Sildenafil binding isotherm of PDE5 indicated KD was 8.3 to 13.3 nM, and low cGMP decreased the KD to 4.8 nM but only slightly increased Bmax to a maximum of 0.61 mol/mol-subunit. Results suggest that these effects occur via cGMP binding to the allosteric cGMP binding sites of PDE5. Results imply that by inhibiting PDE5 and thereby increasing cGMP, sildenafil accentuates its own binding affinity for PDE5, which further elevates cGMP. The data also indicate that after physiological elevation, cGMP may directly stimulate the catalytic site by binding to the allosteric cGMP-binding sites of PDE5, thus causing negative feedback on this pathway.

Vascular complications by compromising the blood flow to the allograft can have significant and sometimes life-threatening consequences after pediatric liver transplantation. High level of suspicion and aggressive utilization of diagnostic modalities can lead to early diagnosis and salvage of the allograft. This review will summarize the current trends in management of vascular complications after pediatric liver transplantation.

Organ shortage is unquestionably the greatest challenge facing the field of transplantation today. Transplant centers are constantly competing with one another for limited numbers of organs for their recipients. Recruitment of specialized transplant surgical expertise and leadership is thought to enable a center to grow in volume and thus profitability in the increasingly difficult world of health care reimbursement. In this study, the pattern of kidney transplants at 13 different centers in the United Network for Organ Sharing's region 1 is examined: the comparison is between transplant volume before and after changes in the centers' leadership between 2000 and 2011. Each center's kidney transplant volume showed a significant increase after a leadership change that ultimately regressed to the center's baseline. This study is the first to show that behavioral changes in transplant center competition cause transient increases in transplant volume that quickly regress back to mean levels.

Background: Hepatitis C (HCV) is the most common indication for liver transplantation in the US. Objective: Since steroids are the major stimulus of viral replication, we postulated that steroid-free immunosuppression might be a safer approach. Methods: From January 1995 to October 2002, we used steroid plus calcineurin inhibitor (CNI) immunosuppression after liver transplantation for HCV (steroid group, n=81). From October 2002 to June 2007, rabbit antithymocyte globulin (RATG) induction, followed by CNI and azathioprine (RATG group, n=73) was utilized. Results: There were no differences in 1- and 3-year patient/allograft survival rates. The incidence of acute rejection rate (19% vs. 28%), of biopsy-proven HCV recurrence (70% vs. 75%), and chronic rejection (6% vs. 9%) were comparable. The mean time to develop recurrent HCV was significantly longer in the RATG group (16.2 vs. 9.2 months, p=0.008). The incidence of severe portal fibrosis appears to be lower in RATG group compared to the steroid group; 14% vs. 4% (p=0.07). Conclusions: RATG induction is safe and effective after liver transplantation for HCV, but has no impact on the incidence of HCV recurrence and patient/allograft survival. However, a significant delay in time to HCV recurrence and a trend toward less rejection and portal fibrosis was observed.

Background: Liver transplantation (LT) for polycystic liver disease (PLD) has evolved to be an option for treating these patients. Patients with PLD suffer from incapacitating symptoms because of very large liver volumes but liver function is preserved until a late stage. Objective/Methods: Herein, we reviewed the outcome of adult patients with PLD who underwent LT in the US comparing pre-MELD (1990–2001) to MELD era (2002–2009). Results: During this period, only 309 patients underwent LT for PLD. The number of LT for PLD is very low comparing the two eras. The percentage of patients who had combined liver and kidney transplantation (CLKT) for this disease has not changed during MELD era (42.8% vs 38.6%). The waiting time for LT (337 vs 272 days) and CLKT (289 vs 220) has increased in MELD era (p

Solid organ transplantation is the treatment of choice in children with end-stage organ failure. With improving methods of transplant surgery and post-transplant care, transplantation is more frequently performed worldwide. However, lifelong and non-specific suppression of the recipient's immune system is a cause of significant morbidity in children, including infection, diabetes, and cancer. There is a great need to develop IS minimization/withdrawal and tolerance induction approaches.