The immune response to a fungus in pancreatic cancer samples.

Pancreatic ductal adenocarcinoma (PDAC) is a poor prognosis cancer with an .aggressive growth profile that is often diagnosed at late stage and that has few curative or therapeutic options. PDAC growth has been linked to alterations in the pancreas microbiome, which could include the presence of the fungus Malassezia. We used RNA-sequencing to compare 14 paired tumor and normal (tumor adjacent) pancreatic cancer samples and found Malassezia RNA in both the PDAC and normal tissues. Although the presence of Malassezia was not correlated with tumor growth, a set of immune- and inflammatory-related genes were up-regulated in the PDAC compared to the normal samples, suggesting that they are involved in tumor progression. Gene set enrichment analysis suggests that activation of the complement cascade pathway and inflammation could be involved in pro PDAC growth.

Navajo Neurohepatopathy : A Case Report and Literature Review Emphasizing Clinicopathologic Diagnosis.

Navajo Neurohepatopathy (NNH) is a rare hepatocerebral mitochondrial DNA (mtDNA) depletion syndrome (MDS) with nonspecific clinical or pathologic features aside from Navajo ancestry. Because of the rarity of NNH, diagnosis rests on close clinicopathologic correlation and appropriate tissue triage for quantitative mtDNA analysis. We present a new case of NNH in which the clinical presentation and H&E liver biopsy histology indicated the need for NNH workup. Quantitative analysis of mtDNA in liver tissue was significantly reduced, and mutational analysis of the MPV17 gene confirmed homozygosity for the NNH-associated missense mutation, R50Q. The patient is now one year post liver transplant and continues to have normal liver function tests but suffers multiple immunosuppression-associated co-morbidities. A comprehensive literature review is provided to assist in diagnosis and management of NNH. (Acta gastroenterol. belg., 2016, 79, 463-469).

Calibration of dual-energy x-ray absorptiometry for bone density.

Bone mineral content (BMC, g) using DEXA (Lunar DPX) was measured on known hydroxyapatite samples in a water bath in the presence of uniform and nonuniform covering of fat-equivalent materials. Selective placement of paraffin over bone had a greater effect than lard in reducing apparent BMC, and polycarbonate plastic had a lesser effect. Measured BMC was 100.1 +/- 1.1% of actual hydroxyapatite weight when (1) fat over bone was about twice the mass of hydroxyapatite, and (2) the surrounding soft tissue was 15-30% fat. There was a linear relationship between observed and expected BMC, area (cm2), and bone mineral density (BMD, g/cm2) measured on an aluminum phantom using either the Lunar DPX or the Hologic QDR-1000. The measured area with the two densitometers was identical, but BMC differed. For both an anthropomorphic phantom and human subjects, use of a constant-threshold (0.2 g/cm2) edge-detection algorithm excluded less low-density bone from the transverse processes than the standard DPX edge-detection algorithm. Differences in edge detection could influence the results obtained with phantoms and in vivo and make system intercomparison difficult.

Computed tomography appearance of the thymus and anterior mediastinum in active Cushing's syndrome.

Computed tomography (CT) evaluation of the thymus and anterior mediastinum is an important aspect of the investigation of patients with ACTH-dependent Cushing's syndrome in order to exclude an ACTH-secreting carcinoid tumor. We have reviewed the CT imaging of the thymus and anterior mediastinum in a series of 85 patients (55 females; median age 41, range 7-77 yr) with active Cushing's syndrome as there are few data on the range of appearances in hypercortisolemic states. One patient had a thymic carcinoid tumor (24 x 18 mm). Of the others, 28/84 (33%) patients showed thymic remnant tissue, consisting of either nodule(s) at least 5 mm diameter (n = 21, mean diameters 12.5 +/- 5 x 9.6 +/- 4 mm), or triangular bilobed glands (n = 7, mean thickness of the body, right and left limbs 25 +/- 7, 14 +/- 3, and 12 +/- 5 mm). Thymic involution appeared in 56/84 (67%) patients, ranging from small nodule(s) of less than 5mm diameter to linear soft tissue strands and complete fatty replacement. Patients with thymic remnant tissue were younger than those with thymic involution (P < 0.05). The thymic carcinoid tumor could be distinguished from remnant tissue on the basis of age and size. The presence of anterior mediastinal nodule(s) in hypercortisolemia need not imply the presence of a thymic carcinoid tumor, although in older patients this should arouse suspicion.

Facial affect recognition in children: a comparison of the performance of children with right and left hemisphere lesions.

This study tests the hypothesis that the right hemisphere is specialized for the processing of emotional information in children, as it is in adults. We compared the performance of eight children with right-hemisphere lesions and eight with left-hemisphere lesions on a test of facial affect recognition. The mean score of the right-hemisphere group fell significantly below that of the left-hemisphere group and normal controls, suggesting that the specialization of the right hemisphere occurs early in development. This finding is consistent with clinical observations that children with right-hemisphere dysfunction manifest a high incidence of difficulty in social interactions.

Determination of radiosensitivity in established and primary squamous cell carcinoma cultures using the micronucleus assay.

In this study, the cytokinesis-block micronucleus assay (CBMN) was used to measure radiosensitivity in three established cell lines (SCC-61, V175 and V134) and 10 primary cell cultures of squamous cell carcinoma (SCC) of the head and neck. Assessment involved optimisation of the assay to determine cytochalasin-B (CB) concentration and sampling time postirradiation. A much closer correlation between dose-response data measured in the clonogenic and micronucleus assays was found when the micronucleus assay was performed under standardised conditions for each cell line (2 micrograms/ml CB: 48 h postirradiation) instead of predetermined optimised assay conditions. This indicates that, for these SCC cell lines, the CBMN assay may be able to predict in vitro radiosensitivity. To be of clinical use in predicting radiosensitivity, the CBMN assay also needs to be evaluated with primary cell cultures. In this study, no relationship between micronucleus frequency at 2 or 6 Gy and patient clinical outcome 12 months following surgery and radiotherapy was seen. Similarly, no association between patient outcome and tumour stage, nodal stage and histology was observed. These CBMN assay data from the primary cell cultures are presently inconclusive as a measure of patient tumour radiosensitivity.

Determination of radiation-induced damage in lymphocytes using the micronucleus and microgel electrophoresis 'Comet' assays.

DNA damage assays may be useful as rapid predictors of normal tissue radiosensitivity in clinical samples. We measured in vitro radiation-induced (2 Gy) damage to lymphocytes from cancer patients and normal healthy donors using both the micronucleus and microgel electrophoresis (Comet) assays simultaneously. For damage assessment, there was a good correlation (P < 0.001) between the mean comet lengths and the fraction of cells with comets. There was no correlation with initial damage, determined as the proportion of cells within a sample that formed comets, in comparison with the mean frequency of micronuclei per binucleate cell. However, there appeared to be an association between the determination of repair proficiency in the Comet assay and the mean frequency of micronuclei per binucleate cell in lymphocytes from cancer patients.

Hepatitis C antibody status and outcomes in renal transplant recipients.

BACKGROUND: Hepatitis occurs frequently in patients with end-stage renal disease. In 1997, 0.7% of patients receiving a renal transplant were positive for hepatitis C antibodies. Concern has been raised as to whether these patients are at an increased mortality risk after renal transplantation compared with patients who are hepatitis C antibody negative. To help answer this question, we analyzed data from the United States Renal Data System from October of 1988 through June of 1998. METHODS: Primary study endpoints were patient death and death censored graft loss. Secondary study endpoints included cardiovascular, infectious, malignant, and infection-related death. Kaplan-Meier survival estimates as well as Cox proportional hazard models were used to evaluate the impact of hepatitis C antibody status on the study endpoints. RESULTS: A total of 73,707 patients were analyzed. Patient survival by Kaplan-Meier analysis was higher in hepatitis C-positive patients, whereas death censored graft survival trended lower in the very long term. By the Cox model, hepatitis C-positive adjusted patient survival is slightly superior to that of hepatitis C-negative patients. CONCLUSIONS: Renal transplant recipients who are hepatitis C antibody positive do not have an increased risk of death after transplantation compared with hepatitis C-negative recipients. The current policy of transplanting hepatitis C-positive patients without active liver disease seems to incur no excess mortality risk.

Interaction of mycophenolate mofetil and HLA matching on renal allograft survival.

INTRODUCTION: The importance of HLA matching for renal transplantation outcomes has been appreciated for several decades. It has been hypothesized that as pharmacologic immunosuppression becomes stronger and more specific, the impact of HLA matching may be vanishing. Mycophenolate Mofetil (MMF) has been demonstrated to both decrease acute rejection and improve three-year graft survival. It is possible that with new immunosuppressive regimens containing MMF the relative effect of HLA matching may be altered. To determine the relative impact of HLA matching in patients on MMF we undertook an analysis of the United States Renal Transplant Data Registry (USRDS). METHODS: All primary, solitary renal transplants registered at the USRDS between January 1995 and June 1997, on initial immunosuppression that included either MMF or AZA were followed until June 1998. Primary study end points were graft and patient survival. Kaplan-Meier analysis was performed to compare AZA vs. MMF treated patients by HLA mismatch. Cox proportional hazard models were used to investigate the interaction between HLA mismatch and AZA versus MMF therapy on the study endpoints. All multivariate analyses were corrected for 13 potential confounding pretransplant variables including intention to treat immunosuppression. RESULTS: A total of 19,675 patients were analyzed (8,459 on MMF and 11,216 on AZA). Overall three year graft survival was higher in the MMF group when compared to the AZA group (87% vs. 84% respectively P<0.001). For both AZA and MMF three-year graft survival improved with fewer HLA donor-recipient mismatches. Comparing zero antigen mismatches to six antigen mismatches, the relative improvement was comparable for both patients on AZA (92.4% vs. 80.6%) and MMF (95.2% vs. 82.9%). By Cox proportional hazard model the relative risk for graft loss decreased significantly in both the AZA and MMF treated patients with increased HLA matching. CONCLUSION: The use of MMF does not obviate the benefits of HLA matching, while HLA matching does not minimize the benefits of MMF on long term graft survival. Our study would suggest that HLA matching and MMF therapy are additive factors in decreasing the risk for renal allograft loss.

Gender differences in the risk for chronic renal allograft failure.

BACKGROUND: Despite the known differences in immunological reactivity between males and females, no differences in graft survival have been described among renal transplant recipients with regard to gender. To address this paradox, we analyzed data from 73,477 primary renal transplants collected in the US Renal Data System database. METHODS: Logistic regression and Cox proportional hazard models were used to investigate the primary study end points, graft loss secondary to acute rejection (AR) or chronic allograft failure (CAF). CAF was defined as graft loss beyond 6 months, not attributable to death, recurrent disease, acute rejection, thrombosis, infection, noncompliance, or technical problems. The models adjusted for 15 covariates including immunosuppressive regimen, and donor and recipient characteristics. RESULTS: The overall 8-year graft and patient survivals were significantly better in female renal transplant recipients compared with male recipients. However graft survival censored for death was not significantly different by gender. By multivariate analysis, females had a 10% increased odds of AR (OR=1.10, CI 1.02-1.12), but conversely a 10% lower risk of graft loss secondary to CAF (RR=0.9, CI 0.85-0.96). The risk for CAF increased significantly with increasing age for both males and females, but this effect was greater for males than for females (P<0.001). CONCLUSION: Although female renal transplant recipients have a similar death censored graft survival compared with males, there are important differences in immunological behavior. Females have a higher risk of AR while having a decreased risk of graft loss secondary to CAF.

Increased impact of acute rejection on chronic allograft failure in recent era.

BACKGROUND: Acute rejection (AR) remains a major risk factor for the development of chronic renal allograft failure (CAF), which is a major cause of late graft loss. With the introduction of several newer immunosuppressive agents (e.g., mycophenolate mofetil, tacrolimus and neoral) acute rejection rates have been steadily decreasing. However, the incidence of CAF has not decreased as dramatically as the incidence of acute rejection. One possible explanation is that the impact of AR on CAF is changing. The goal of this study was to analyze the relative impact of AR era on the development of CAF. METHODS: We evaluated 63,045 primary renal transplant recipients reported to the USRDS from 1988 to 1997. CAF was defined as graft loss after 6 months posttransplantation, censored for death, acute rejection, thrombosis, infection, surgical complications, or recurrent disease. A Cox proportional hazard model correcting for 15 possible confounding factors evaluated the relative impact of AR on CAF. The era effect (years 1988-1989, 1990-1991, 1992-1993, 1994-1995 and 1996-1997) was evaluated by an era versus AR interaction term. RESULTS: An AR episode within the first 6 months after transplantation was the most important risk factor for subsequent CAF (RR=2.4, CI 2.3-2.5). Compared with the reference group (1988-89 with no rejection), having an AR episode in 1988-89, 1990-1991, 1992-1993, 1994-1995, and 1996-1997, conferred a 1.67, 2.35, 3.4, 4.98 and 5.2-fold relative risk for the subsequent development of CAF (P<0.001). CONCLUSIONS: Independently of known confounding variables, the impact of AR on CAF has significantly increased from 1988 to 1997. This effect may in part explain the relative lack of improvements in long term renal allograft survival, despite a decline in AR rates.

Relationship of recipient age and development of chronic allograft failure.

BACKGROUND: The elderly are the fastest growing segment of the end stage renal disease (ERSD) population. Older renal transplant recipients experience fewer acute rejection episodes than do younger patients. Despite this, death censored graft survival is no better in these older transplant recipients than in younger recipients. We examined the United States Renal Data System (USRDS) database to determine whether recipient age itself has an independent effect on the development of chronic allograft failure (CAF). METHODS: We analyzed 59,509 patients from the files of the USRDS. To determine whether age was an independent risk factor for CAF, the population was analyzed separately for Caucasians, African-Americans, and other ethnic groups. All renal transplant recipients from 1988 to 1997 were examined. Both univariate and multivariate analysis were performed using chronic allograft failure as the outcome of interest. RESULTS: Actuarial 8-year censored graft survival was significantly decreased in the older age groups 67% for ages 18-49 vs. 61.8% for ages 50-64 vs. 50.7% for ages 65+ (P<0.001). In the multivariate analysis, recipient age was a strong and independent risk factor for the development of chronic allograft failure in Caucasians (RR 1.29 for ages 50-64, RR 1.67 for ages older than 65). These findings were reinforced by an analysis that was restricted to living donor transplants without acute rejection. CONCLUSION: In Caucasians increased recipient age is an independent risk factor for the development of chronic renal allograft failure.

African-American renal transplant recipients experience decreased risk of death due to infection: possible implications for immunosuppressive strategies.

INTRODUCTION: African-American renal transplant recipients tend to experience more acute rejection episodes and have shorter graft survival than Caucasian renal transplant recipients. Various factors have been posited to be responsible for this difference, including relative under immunosuppression. We reasoned that by looking at the balance of acute rejections versus death due to infection, we could ascertain whether African-American renal recipients might have more reserve to tolerate an increase in pharmacological immunosuppression. METHODS: We analyzed the United States Renal Data System (USRDS) data from 1987 to 1997 regarding acute rejection episodes and infectious deaths. All other pertinent factors were gathered for a multivariate analysis. A total number of 68,885 adult renal transplant recipients were analyzed. RESULTS: When corrected for all covariates, the relative risk for acute rejection (1.3) was higher although the relative risk for infectious death was lower (0.7) in African-Americans as compared with Caucasians (P<0.01). CONCLUSION: Our study would indicate that relative to Caucasians, African-American renal transplant recipients are at decreased risk for infectious death and therefore may tolerate the more intensive immunosuppression that may be necessary to narrow the gap in acute rejection rates between African-Americans and Caucasian renal transplant recipients.

The impact of simultaneous pancreas-kidney transplantation on long-term patient survival.

BACKGROUND: Simultaneous pancreas-kidney transplantation (SPK) ameliorates the progression of microvascular diabetic complications but the procedure is associated with excess initial morbidity and an uncertain effect on patient survival when compared with solitary cadaveric or living donor renal transplantation. We evaluated mortality risks associated with SPK, solitary renal transplantation, and dialysis treatment in a national cohort of type 1 diabetics with end-stage nephropathy. METHODS: A total of 13,467 adult-type 1 diabetics enrolled on the renal and renal-pancreas transplant waiting list between 10/01/88 and 06/30/97 were followed until 06/30/98. Time-dependent mortality risks and life expectancy were calculated according to the treatment received subsequent to wait-list registration: SPK; cadaveric kidney only (CAD); living donor kidney only (LKD) transplantation; and dialysis [wait-listed, maintenance dialysis treatment (WLD)]. RESULTS: Adjusted 10-year patient survival was 67% for SPK vs. 65% for LKD recipients (P=0.19) and 46% for CAD recipients (P<0.001). The excess initial mortality normally associated with renal transplantation and the risk of early infectious death was 2-fold higher in SPK recipients. The time to achieve equal proportion of survivors as the WLD patients was 170, 95, and 72 days for SPK, CAD, and LKD recipients, respectively (P<0.001). However, the adjusted 5-year morality risk (RR) using WLD as the reference and the expected remaining life years were 0.40, 0.45, and 0.75 and 23.4, 20.9, and 12.6 years for SPK, LKD, and CAD, respectively. There was no survival benefit in SPK recipients > or =50 years old (RR=1.38, P=0.81). CONCLUSIONS: Among patients with type 1 DM with end-stage nephropathy, SPK transplantation before the age of 50 years was associated with long-term improvement in survival compared to solitary cadaveric renal transplantation or dialysis.

Mycophenolate mofetil reduces late renal allograft loss independent of acute rejection.

BACKGROUND: Mycophenolate Mofetil (MMF) has been shown to significantly decrease the number of acute rejection episodes in renal transplant recipients during the 1st year. A beneficial effect of MMF on long-term graft survival has been more difficult to demonstrate. This beneficial effect has not been detected, despite the impact of acute rejection on the development of chronic allograft nephropathy and experimental evidence that MMF may have a salutary effect on chronic allograft nephropathy independent of that of rejection. METHODS: Data on 66,774 renal transplant recipients from the U.S. renal transplant scientific registry were analyzed. Patients who received a solitary renal transplant between October 1, 1988 and June 30, 1997 were studied. The Cox proportional hazard regression was used to estimate relevant risk factors. Kaplan-Meier analysis was performed for censored graft survival. RESULTS: MMF decreased the relative risk for development of chronic allograft failure (CAF) by 27% (risk ratio [RR] 0.73, P<0.001). This effect was independent of its outcome on acute rejection. Censored graft survival using MMF versus azathioprine was significantly improved by Kaplan-Meier analysis at 4 years (85.61% v. 81.9%). The effect of an acute rejection episode on the risk of developing CAF seems to be increasing over time (RR=1.9, 1988-91; RR=2.9, 1992-94; RR=3.7, 1995-97). CONCLUSION: MMF therapy decreases the risk of developing CAF. This improvement is only partly caused by the decrease in the incidence of acute rejection observed with MMF; but, is also caused by an effect independent of acute rejection.

Impact of pre-existing donor hypertension and diabetes mellitus on cadaveric renal transplant outcomes.

Hypertension (HTN) and diabetes mellitus (DM) predispose to systemic atherosclerosis with renal involvement. The prevalence of HTN and DM in cadaveric renal donors (affected donors) and the results of transplantation are unknown. We investigated these issues with national data from the US Renal Data System. A total of 4,035 transplants from affected donors were matched 1:1 with unaffected controls according to donor age and race, recipient race, and year of transplantation. Graft and patient survival were estimated. Among the 25,039 solitary renal transplantations performed between July 1, 1994, and June 30, 1997, cadaveric renal transplants from donors with HTN accounted for 15%, and donors with DM, 2%. Programs with 1-year cadaveric renal graft survival rates greater than 90% had 50% less affected donors compared with programs having 1-year cadaveric renal graft survival rates of 85% or less. Compared with donor-age-matched controls, transplants from affected donors were at minimally increased risk for primary nonfunction, delayed graft function, and acute rejection. Three-year graft survival rates were 71% in affected donor organs and 75% in controls (P = 0.001). Compared with controls, duration of HTN was an independent risk factor for graft survival (3-year graft survival rates, 75% versus 65%; relative risk = 1.36 for HTN >10 years; P < 0.001). A substantial fraction of cadaveric renal donors have preexisting HTN. Programs transplanting fewer affected donor kidneys had better than average results. Because the negative impact of donor HTN and DM on transplant outcome was of moderate degree except when the duration of donor HTN was greater than 10 years, use of affected donors should not be discouraged, but graft and patient survival analyses should account for their presence.

Racial disparities in access to simultaneous pancreas-kidney transplantation in the United States.

The purpose of our study is to assess the extent of racial differences in the access to simultaneous pancreas-kidney (SPK) transplantation and evaluate the potential influence of socioeconomic factors on access to transplantation. We performed a retrospective analysis of the US Renal Data System and United Network for Organ Sharing data on all patients with end-stage renal disease (ESRD) due to diabetes mellitus from 1988 to 1996 (n = 562, 814), including all dialysis, wait list, and transplant patients. Racial differences in incidence, prevalence, insurance coverage, employment status, and transplantation rates were calculated. Caucasians had the highest prevalence of ESRD caused by type 1 diabetes (73%), followed by blacks (22%), Hispanics (3%), Native Americans (2%), and others (<1%). Both blacks and Native Americans increased their annual incidence of ESRD caused by insulin-dependent diabetes mellitus by 10% compared with only a 3.5% increase in Caucasians, whereas incidence rates increased annually by almost 8% for both blacks and Native Americans compared with a 3% increase for Caucasians. However, Caucasians received 92% of all SPK transplants, whereas all other racial groups combined received a disproportionate minority of the remaining transplants. Lack of private insurance and unemployment status were associated with annual changes in both incidence of ESRD caused by type 1 diabetes and SPK transplant rates. In conclusion, we observed striking racial disparities for access to SPK transplantation in the United States today, which may be related to employment status, access to private insurance, and subsequent health care. Our preliminary data support current efforts to encourage Medicare and Medicaid coverage for all patients requiring SPK transplantation regardless of racial or financial status.

A novel dye exclusion assay for measurement of cell response following in vitro exposure to radiation or drugs.

A novel dye exclusion assay based on differential staining of fixed cells has been evaluated using the MOLT4 (T-lymphoblastic leukaemia) and DAUDI (Burkitt lymphoma) cell lines. Reproducible differential staining was found with fixed samples kept for up to 2 months. A small increase (less than 13%) in the proportion of stained cells was observed over the first 30 days in fixative. Reproducible dose-response data were obtained with cells treated with radiation or drugs and assayed after 4 days in culture. This ability to fix cells prior to measurement of viability is of general use particularly where time constraints prevent haemocytometer counting. More specifically, it may have potential use in the field of chemosensitivity testing particularly where large sample numbers require rapid processing.

In vitro chemosensitivity testing in chronic lymphocytic leukaemia patients.

Twenty-nine samples from eighteen patients with chronic lymphocytic leukaemia (CLL) were used in a direct comparison of in vitro response to chlorambucil measured in a metabolic (MTT) and dye exclusion (D.Ex) assay. Reduced ability to produce formazan corresponded to a reduced number of dye-excluding viable cells and a significant correlation was found between dose-response measured in the two assays. Initial low absorbance values obtained with untreated control cells in the MTT assay were effectively overcome by increasing both the cell seeding density and MTT exposure time with the consequent increase in assay sensitivity. The MTT assay provided qualitatively similar dose-response data to that obtained in the D.Ex assay. A wide range in in vitro response was seen for both pretreatment and treatment patient groups. In vitro dose-responses were seen to coincide with decreasing or stable white cell counts, taken around the time of sampling, in samples from 4 patients. Less marked dose-responses were observed for 2 patients considered clinically resistant to chlorambucil. The MTT assay would seem, therefore, to be applicable to in vitro assay of cell response in CLL.

The sensitivity of chronic lymphocytic leukaemia lymphocytes to irradiation in vitro.

The inhibition of [3H]-thymidine incorporation into the DNA of mitogen-stimulated chronic lymphocytic leukaemia lymphocytes by chlorambucil or gamma-irradiation in vitro was measured in a series of patients, some of whom were untreated, some treated and some who were showing resistance to first-line or second-line treatment. There was evidence of resistance to irradiation developing in parallel with that to chlorambucil. The resistance to chlorambucil in chronic lymphocytic leukaemia (CLL) is not necessarily due to altered drug transport or metabolism but to a more fundamental process affecting DNA damage.