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Intestinal graft-versus-host disease (GVHD) remains a devastating complication after allogeneic hematopoietic stem cell transplantation (HSCT). Although it has been well established that gut-tropic donor T cells expressing integrin α4β7 are required to cause intestinal damage, the factors that control the induction of this pathogenic T cell population remain to be identified. Retinoic acid (RA) plays an important role in inducing α4β7 expression on T cells. In this study, we showed that gene expression of retinaldehyde dehydrogenase, the key enzyme involved in RA biosynthesis, is significantly increased in the spleen and mesenteric lymph nodes (MLNs) of irradiated mice. In a C57BL/6-into-B6D2F1 allogeneic HSCT model, irradiation significantly increased the induction of α4β7 + -donor T cells in mesenteric lymph nodes and spleen. Furthermore, we found that the RA pathway modulates the ability of dendritic cells to imprint gut-homing specificity on alloreactive T cells. We also showed that host dendritic cell RA signaling influences GVHD risk. Our studies identified radiation and recipient RA signaling as 2 primary factors that dictate the magnitude of gut-homing donor T cell induction after allogeneic HSCT. Attenuating radiation-associated inflammation and modulating host RA signaling represent feasible strategies to mitigate intestinal GVHD by reducing gut-seeking pathogenic donor T cells., (© 2019 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Acute fatty liver of pregnancy (AFLP) often resolves after pregnancy delivery but can progress to acute liver failure necessitating liver transplantation. We performed a retrospective review of the national Scientific Registry of Transplant Recipients (SRTR) data to identify all women in the United States undergoing liver transplantation (LT) for acute liver failure (ALF) from AFLP from 1991 to 2015, and compared to outcomes in women of childbearing age undergoing transplant for ALF from acetaminophen and ALF from other etiologies. Women with AFLP were likely to be on life support at time of LT and had high rates of renal dysfunction (median Cr 2.1, IQR 1.2-2.3), and hyperbilirubinemia (median bilirubin 17.1, IQR 11.0, 19.9). Although their early and late LT survival outcomes were comparable to the other indications for LT, cumulative 5-year graft survival was numerically lower among AFLP patients (54%, 95% CI, 27-76) compared to APAP (70%, 95% CI, 63-77) and "Other ALF" (76%, 95% CI, 72-80) groups. In conclusion, although AFLP is a rare indication for LT, AFLP patients were as sick or sicker than other women of childbearing age undergoing LT for ALF. Worsened graft survival may be related to higher rates of rejection in the AFLP group., (© 2019 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Nonstandard exception requests (NSERs), for which transplant centers provide patient-specific narratives to support a higher Model for End-stage Liver Disease/Pediatric End-stage Liver Disease score, are made for >30% of pediatric liver transplant candidates. We describe the justifications used in pediatric NSER narratives 2009-2014 and identify justifications associated with NSER denial, waitlist mortality, and transplant. Using United Network for Organ Sharing data, 1272 NSER narratives from 1138 children with NSERs were coded for analysis. The most common NSER justifications were failure-to-thrive (48%) and risk of death (40%); both associated with approval. Varices, involvement of another organ, impaired quality of life, and encephalopathy were justifications used more often in denied NSERs. Of the 25 most prevalent justifications, 60% were not associated with approval or denial. Waitlist mortality risk was increased when fluid overload or "posttransplant complication outside standard criteria" were cited and decreased when liver-related infection was noted. Transplant probability was increased when the narrative mentioned liver-related infections, and fluid overload for children <2 years old; it decreased when "posttransplant complications outside standard criteria" and primary sclerosing cholangitis were cited. This analysis provides novel insight and suggests targets for future consideration in outcomes research and exception criteria. Changes in the allocation system are needed to ensure equity and optimize outcomes for all pediatric candidates., (© 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Nonstandard exceptions requests (NSERs), in which transplant centers appeal on a case-by-case basis for Pediatric End-Stage Liver Disease/Mayo End-Stage Liver Disease points, have been highly utilized for pediatric liver transplant candidates. We evaluated whether NSE outcomes are associated with waitlist and posttransplant mortality. United Network for Organ Sharing (UNOS) Scientific Registry of Transplant Recipients data on pediatric liver transplant candidates listed in 2009-2014 were analyzed after excluding those granted automatic UNOS exceptions. Of 2581 pediatric waitlist candidates, 44% had an NSE request. Of the 1134 children with NSERs, 93% were approved and 7% were denied. For children 2-18 years at listing, NSER denial increased the risk of waitlist mortality or removal for being too sick (subhazard ratio 2.99, 95% confidence interval [CI] 1.26-7.07, p = 0.01 in multivariate analysis). For children younger than 2 years, NSER denial did not impact waitlist mortality/removal. Children with NSER approved had reduced risk of graft loss 3 years posttransplant in univariate but not multivariable analysis (odds ratio 0.73, 95% CI 0.53-1.01, p = 06). Those with NSER denial had a higher risk of posttransplant death than those with no NSER (hazard ratio 2.43, 95% CI 0.99-5.95, p = 0.05, multivariable analysis), but NSER approval did not impact posttransplant death. Further research on NSER utilization in pediatric liver transplant is needed to optimize organ allocation and outcomes for children., (© Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Survival benefit (SB) for first liver transplantation (LT) is favorable at Model for End-Stage Liver Disease (MELD)≥15. Herein, we identify the MELD threshold for SB from repeat liver transplantation (ReLT) by recipient hepatitis C virus (HCV) status and donor risk index (DRI). We analyzed lab MELD scores in new United Network for Organ Sharing registrants for ReLT from March 2002 to January 2010. Risk of ReLT graft failure≤1 year versus waitlist mortality was calculated using Cox regression, adjusting for recipient characteristics. Of 3057 ReLT candidates, 54% had HCV and 606 died while listed. There were 1985 ReLT recipients, 52% had HCV and 567 ReLT graft failures by 1 year. Unadjusted waitlist mortality and post-ReLT graft failure rates were 416 (95% confidence interval [CI] 384-450) and 375 (95% CI 345-407) per 1000 patient-years, respectively. Waitlist mortality was higher with increasing waitlist MELD (p<0.001). The MELD for SB from ReLT overall was 21 (21 in non-HCV and 24 in HCV patients). MELD for SB varied by DRI in HCV patients (MELD 21, 24 and 27 for low, medium and high DRI, respectively) but did not vary for non-HCV patients. Compared to first LT, ReLT requires a higher MELD threshold to achieve an SB resulting in a narrower therapeutic window to optimize the utility of scarce liver grafts., (© Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Damage to the gastrointestinal tract during graft-versus-host disease (GVHD) is one of the major causes of morbidity and mortality in allogeneic hematopoietic stem cell transplant (HSCT) recipients. In the current study, we identified a critical role for the retinoic acid (RA) signaling pathway in the induction and propagation of gastrointestinal GVHD. The administration of exogenous RA significantly increased expression of the gut-homing molecules, CCR9 and α4β7, on donor T cells in mesenteric lymph nodes, and augmented the accumulation of proinflammatory CD4(+) and CD8(+) T cells within the gut mucosa, leading to a selective exacerbation of colonic GVHD and increased overall mortality. Conversely, depletion of RA in recipient mice by vitamin A deprivation resulted in a dramatic reduction of gut-homing molecule expression on donor T cells after HSCT. Significantly, absence of the RA receptor-α on donor T cells markedly attenuated the ability of these cells to cause lethal GVHD. This observation was attributable to a significant reduction in pathological damage within the colon. These findings identify an organ-specific role for RA in GVHD and provide evidence that blockade of the RA signaling pathway may represent a novel strategy for mitigating the severity of colonic GVHD.

Background & Aims: IL28B single nucleotide polymorphisms are strongly associated with spontaneous HCV clearance and treatment response in non-transplant populations. A DDX58 single nucleotide polymorphism is associated with the antiviral response of innate lymphocytes. We aimed at evaluating the associations of donor and recipient IL28B (rs12979860 and rs8099917) and DDX58 (rs10813831) genotypes with severity of HCV recurrence after liver transplantation., Methods: In a case-control study of 523 liver transplantation recipients with HCV, we matched severe with mild recurrent HCV based on 2-year clinical and histologic follow-up. A total of 440 liver transplantation recipients (severe, n=235; mild, n=205) with recipient DNA and 225 (severe, n=123; mild, n=102) with both recipient and donor DNA were analyzed., Results: IL28B [rs12979860, non-CC (vs. CC) and rs8099917, non-TT (vs. TT)] in the recipient-only analysis had higher risk of severe recurrent HCV [OR 1.57 and 1.58, p<0.05]. However, for the 225 with donor and recipient DNA, IL28B rs12979860 CC (vs. non-CC) and rs8099917 TT (vs. non-TT) and DDX58 rs10813831 non-GG (vs. GG) were associated with more (not less) severe recurrent HCV. The greatest risk of severe recurrent HCV was for rs12979860 CC donors in non-CC recipients (OR 7.02, p <0.001, vs. non-CC donor/recipient) and for rs8099917 TT donors in non-TT recipients (OR 5.78, p=0.001, vs. non-TT donor/recipient). These associations persisted after controlling for donor age, donor race, and donor risk index., Conclusions: IL28B and DDX58 single nucleotide polymorphisms that are favorable when present in the non-transplant setting or in the recipient are unfavorable when present in a donor liver graft., (Copyright © 2013 European Association for the Study of the Liver. All rights reserved.)

Several diseases have been clinically or genetically related to cystic fibrosis (CF), but a consensus definition is lacking. Here, we present a proposal for consensus guidelines on cystic fibrosis transmembrane conductance regulator (CFTR)-related disorders (CFTR-RDs), reached after expert discussion and two dedicated workshops. A CFTR-RD may be defined as "a clinical entity associated with CFTR dysfunction that does not fulfil diagnostic criteria for CF". The utility of sweat testing, mutation analysis, nasal potential difference, and/or intestinal current measurement for the differential diagnosis of CF and CFTR-RD is discussed. Algorithms which use genetic and functional diagnostic tests to distinguish CF and CFTR-RDs are presented. According to present knowledge, congenital bilateral absence of vas deferens (CBAVD), acute recurrent or chronic pancreatitis and disseminated bronchiectasis, all with CFTR dysfunction, are CFTR-RDs., (Copyright © 2011 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

It is often challenging for the clinician interested in cystic fibrosis (CF) to interpret molecular genetic results, and to integrate them in the diagnostic process. The limitations of genotyping technology, the choice of mutations to be tested, and the clinical context in which the test is administered can all influence how genetic information is interpreted. This paper describes the conclusions of a consensus conference to address the use and interpretation of CF mutation analysis in clinical settings. Although the diagnosis of CF is usually straightforward, care needs to be exercised in the use and interpretation of genetic tests: genotype information is not the final arbiter of a clinical diagnosis of CF or CF transmembrane conductance regulator (CFTR) protein related disorders. The diagnosis of these conditions is primarily based on the clinical presentation, and is supported by evaluation of CFTR function (sweat testing, nasal potential difference) and genetic analysis. None of these features are sufficient on their own to make a diagnosis of CF or CFTR-related disorders. Broad genotype/phenotype associations are useful in epidemiological studies, but CFTR genotype does not accurately predict individual outcome. The use of CFTR genotype for prediction of prognosis in people with CF at the time of their diagnosis is not recommended. The importance of communication between clinicians and medical genetic laboratories is emphasized. The results of testing and their implications should be reported in a manner understandable to the clinicians caring for CF patients.

Chromatographic separations of new growth hormone secretagogue compounds were developed to support structure-activity relationship (SAR) studies in conjunction with lead optimization. These new compounds differed from Merck's MK-677 by having two chiral centers and thus diastereomeric mixtures were generated. Separation of initial compounds in the SAR was achieved on a Kromasil C18 column using an ammonium acetate buffer and acetonitrile. However, additional candidates were not separable on C18 columns and a chiral Kromasil CHI-DMB column was used to resolve the diastereomeric compounds. The Kromasil CHI-DMB packing was also used in a preparative chromatographic system to resolve multigram quantities of secretagogue candidates for testing. Chiral separations of different intermediates were also developed in support of evolution of an asymmetric synthetic route. This report summarizes development of the preparative chromatographic system used to purify diastereomeric mixtures and chiral separations of intermediates in the synthesis.

Pial arteries play a key role in the regulation of human cerebral blood flow. However, many of the features and mechanisms that regulate the tone and diameters of these vessels cannot be studied in situ. One approach is to study in vitro segments of arteries obtained during neurosurgical procedures. The ratios of arterial media thickness to lumen diameter and of the capacity to develop wall force to lumen diameter have important functional consequences and are known to change in disease. Experiments were carried out on pial arteries from normotensive humans to determine the way in which these parameters vary with vessel size. Vessel dimensions--media thickness and lumen diameter were derived from fixed sections using quantitative morphometry. Wall force was measured using a resistance artery myograph. The ratio of media thickness to lumen diameter and of maximum tension developed to lumen diameter both increased as vessel diameter decreased. These ratios do not change over the age range of 15-75 years. These findings show that although in vivo intralumenal pressure falls as human pial arteries become smaller, their media thickness and capacity to develop tone increase.

Fibrosing colonopathy was first described in cystic fibrosis (CF) children in 1994. We have done a nested case-control study to identify possible associations with this condition. A case ascertainment within the UK CF population to identify any cases that occurred between January, 1984, and April, 1994, found 14 cases, all under 14 years and confirmed by independent histopathological review. All had presented since April, 1993; 12 were boys and six had received some or all of their care in Liverpool. Each case was matched, by date of birth, with four controls from the UK CF Registry. Information was obtained about cases and controls from their case records and by a structured interview with the families. In the 12 months before surgery, there was an association between the occurrence of fibrosing colonopathy and use of high-strength pancreatic enzyme preparations. This association was dose related. Odds ratio per extra 1000 high-strength capsules was 1.45 (95% CI 1.14-1.84). For use of protease, the odds ratio per million extra units per kg was 1.55 (1.19-2.03). For usage of individual high-strength products at any time during the 12 months before surgery some differences were observed; for Creon 25000 the odds ratio was 0.38 (0.10-1.42), for Nutrizym 22 43.4 (2.51-751), and for Pancrease HL 8.4 (1.95-36.1). These last two confidence intervals are extremely wide and compatible with these two products having the same odds ratios. Laxative use was independently predictive (odds ratio 2.42 [1.20-4.94]). We conclude that there is a dose-related association between high-strength pancreatic enzyme preparations and fibrosing colonopathy.

This study compared perceptions of 129 elderly cardiac patients regarding their health status and self-management skills with corresponding assessments by outpatient nursing staff members. Nurse-patient perceptions were most congruent on general questions regarding the heart condition. Differences were most apparent regarding how aware patients were of being asked to follow a regimen for managing their heart problems; what specific components comprised the regimens the patients were to follow; and how much confidence patients had in their ability to comply with specific components of the regimen. Congruence in perceptions of nurses and patients varied by the sex of the patient. Findings suggest that careful and continuous assessment of patients' perceptions about their condition and ongoing instruction regarding specifics of the therapeutic regimen are key elements in efforts to enhance elderly patients' self-management skills.

Adrenergic secretory responses of submandibular glands from control subjects and cystic fibrosis patients have been studied in vitro. In control tissues, isoproterenol (10 mumol/l) and noradrenaline (10 mumol/l) increased release of mucins and amylase to a similar extent (approximately 3-fold) and their actions were mediated by stimulation of beta-adrenergic receptors. In cystic fibrosis tissues, isoproterenol did not significantly increase release of mucins or amylase above the basal rate during 40 min incubation, whereas secretion in response to noradrenaline was not significantly different from that in control tissues. In the presence of a phosphodiesterase inhibitor, secretion of mucins and amylase in response to isoproterenol (10 mumol/l) in cystic fibrosis tissues was increased to the same level as that of noradrenaline (10 mumol/l); giving the same pattern of adrenergic responses in cystic fibrosis tissues as in control. The results suggest that overactivity of phosphodiesterase in cystic fibrosis cells might be the cause of the observed decreased secretion in response to a beta-adrenergic agonist.

The in-vitro investigation of secretory responses of submandibular tissues from three cystic fibrosis (CF) patients and four control subjects showed that responses to a beta-adrenergic stimulus (isoproterenol) were much poorer in CF cells than in control cells. The beta-adrenergic secretory responses of the CF cells (as measured by amylase and mucin secretion) were increased in the presence of 3-isobutyl-l-methyl xanthine, a cyclic nucleotide phosphodiesterase inhibitor. Perhaps an alteration in a regulator of cyclic adenosine monophosphate and Ca2+ metabolism in CF cells is responsible for the decrease in beta-adrenergic function. This proposal would account for the defective regulation of protein secretion, Cl- transport, and Ca2+ homoeostasis in CF exocrine cells and thus might be directly related to the genetic defect.

Cystic fibrosis serum stimulated release of mucins from rat submandibular acini to a significantly greater degree than did control serum. This action was not due to non-specific cell lysis, as monitored by lactate dehydrogenase release and was not accompanied by increases in 45Ca2+-efflux. The actions of cystic fibrosis serum and control serum in stimulating amylase release from rat exocrine pancreatic acini could not be distinguished. Thus, a specific action of cystic fibrosis serum in increasing mucin secretion, but not calcium permeability, in rat exocrine acini has been demonstrated.

A characteristic alteration in the distribution of human red cell phospholipids represents an artifact due to autoxidation of the lipid extract. This alteration is manifested on silicic acid chromatography by a decrease mainly in the phosphatidyl ethanolamine and phosphatidyl serine fractions (probably because of their abundance of highly unsaturated fatty acids) and an increase in the phospholipid recovered with the more polar fractions, sphingomyelin and lysolecithin. No evidence was found for "lysocephalin" formation or plasmalogen breakdown in dry lipid extracts after autoxidation by exposure to air at room temperature for 24-35 hr. On thin-layer chromatography, however, the ninhydrin-positive streaking in the autoxidized samples may be erroneously attributed to the presence of "lyso" derivatives. When the alterations in lipid distribution described above are found, the possibility of this artifact should be considered.

Improved methods for lipid analysis that have been developed recently were employed to reevaluate the phospholipid composition, the fatty acid and fatty aldehyde composition of the total phospholipid, and the fatty acid composition of the individual phospholipids of normal human red cells. Thirty-three fatty acids and five fatty aldehydes were estimated and tentatively identified in the total phospholipid of normal human red cells. Additional minor components were evident. The major individual phospholipids were isolated by silicic acid thin-layer chromatography and quantified. The fatty acid compositions of phosphatidyl ethanolamine, phosphatidyl serine, lecithin, and sphingomyelin were determined. Each of these phospholipids showed a distinctive and characteristic fatty acid pattern.

Exposure of human red cells to 2 N HCl for 18-20 hr at 110 degrees C appears to release the total fatty acid, which can then be esterified for GLC analysis. This technique is simpler and may be more reliable than the conventional methods that depend on lipid extraction of the red cells.

The composition of the phospholipids and of the total phospholipid fatty acids was determined in the plasma of 10 normal subjects. In addition the fatty acid composition of the plasma phosphatidyl ethanolamine, phosphatidyl serine, lecithin, sphingomyelin, and lysolecithin of 6 of the subjects was measured. A wide array of fatty acids was found in the plasma total phospholipid similar to that found previously in red cell total phospholipid. The fatty acid composition in the plasma phospholipids of a given subject reflected that in his red cell phospholipids. Each individual phospholipid displayed a distinctive fatty acid pattern, which was generally similar to that of the corresponding phospholipid of red cells, although some marked differences in individual fatty acid levels between the corresponding phospholipids of plasma and red cells were evident. The high percentage of unsaturated fatty acids found in plasma lysolecithin suggests that this phospholipid did not arise entirely through the enzymatic cleavage of the -fatty acid of lecithin.