Mutation in the Hepatitis E Virus Polymerase and Outcome of Ribavirin Therapy

Hepatitis E virus (HEV) can lead to chronic infection in solid-organ transplant patients. Ribavirin is efficient for treatment of chronically infected patients. Recently, the1634R mutation in the HEV polymerase has been associated with treatment failure. However, it is unclear if this mutation can be used as a prognostic marker of treatment outcome. We studied the prevalence of the 1634R mutation in the HEV polymerase of patients starting ribavirin therapy, the influence of the 1634R variants on the viral response, the frequency of the 1634R mutation in patients whose treatment failed, and its impact on ribavirin retreatment. We analyzed pretreatment samples from 63 solid-organ transplant patients with chronic hepatitis E using deep sequencing; 42 patients had a sustained virologic response (SVR), and 21 were non-SVR patients. We detected the 1634R variant by deep sequencing in 36.5% (23/63) of the patients (proportions, 1.3 to 100%). The 1634R variant was detected in 31.0% (13/42) of baseline plasma samples from patients with SVR and in 47.6% (10/21) in the other patients (P = 0.2). The presence of this mutation did not influence the initial decrease in viral RNA. Lastly, a second prolonged ribavirin treatment led to SVR in 70% of the patients who initially did not have SVR, despite the presence of the 1634R variant. We conclude that the presence of the 1634R variant at ribavirin initiation does not lead to absolute ribavirin resistance. Although its proportion increased in patients whose treatment failed, the presence of the 1634R variant did not compromise the response to a second ribavirin treatment.     

Corticosteroid avoidance in adult kidney transplant recipients under rabbit anti‐T‐lymphocyte globulin,mycophenolate mofetil and delayed cyclosporine microemulsion introduction

We conducted the first prospective, randomized, open‐label multicenter study in low‐immunologic risk adult recipients of primary cadaver kidney transplants receiving rabbit anti‐T‐lymphocyte globulin, mycophenolate mofetil, cyclosporine microemulsion introduced on day 5, with and without corticosteroids. Patients were randomly assigned according to age and cold ischemia time to receive corticosteroids for at least 6 months or no corticosteroids at all. The main efficacy evaluation criterion was acute rejection (including all treated episodes and those biopsy‐confirmed) during the first year following transplantation. For this purpose, this report includes the actual results of the whole 12‐month follow‐up of all randomized patients. For efficacy analysis, 98 patients were evaluated in the Steroid avoidance group and 99 in the Steroid maintenance group. Taken as a whole, 81% of the patients (n = 159) never received anti‐rejection treatment. From the 38 patients who received anti‐rejection treatment, 25 (25.5%) were in the Steroid avoidance group and 13 (13.1%) in the Steroid maintenance group (P < 0.031), experiencing respectively 17 (17.3%) and 7 (7.1%) biopsy‐proven first episodes of acute rejection (P < 0.031). Borderline changes (6 vs. 3) were not considered as biopsy‐proven acute rejections. Onset of first rejection was significantly shorter in the Steroid avoidance group (P < 0.027). First‐line anti‐rejection treatment response, need for any rescue therapy, as well as histologic severity of rejection episodes did not statistically differ between the groups. One‐year post‐transplantation analysis showed no differences in delayed graft function, serum creatinine, creatinine clearance, 24‐h proteinuria, as well as serious adverse events between the groups. De novo diabetes (P < 0.07) or dyslipidemia (P < 0.01) as well as newly diagnosed malignancies (P < 0.059) were however more frequently observed in the Steroid maintenance group. At the end of the first post‐transplant year, 99% of patients in the Steroid avoidance group and 97% of patients in the Steroid maintenance group were respectively alive (P = 0.34), with respectively 95% and 93.2% of functioning kidney grafts (P = 0.62). Our results showed that total avoidance of corticosteroids from the day of transplantation was associated with a significantly increased number of clinically diagnosed and treated, and biopsy‐proven acute rejections during the first year of transplantation. Nevertheless, overall outcome, 1‐year patient and graft survival as well as renal function were similar, and the patients in the Steroid avoidance group exhibited a lower incidence of de novo dyslipidemia, diabetes mellitus and malignancies often associated with steroid treatment (Clinical Trials.gov NCT00200551).     

Impact of very early high doses of recombinant erythropoietin on anemia and allograft function in de novo kidney‐transplant patients

After kidney transplantation, occurrence of anemia in the early post‐transplant period (<1 month) is high and arises out of issues that are multifactorial. We performed a retrospective single‐center study to assess whether delivery of high doses of erythropoietin‐stimulating agents (ESA) within the first week of kidney transplantation, translates at 1 month post‐transplant, in to causing less anemia and whether it has an impact on allograft function. Ninety‐nine patients were not given ESA (group I), whereas 82 were (250 IU/kg/week; group II). All patients had similar pretransplant and baseline (day 0) variables. Similar numbers of group II patients were still receiving ESA by day 14 (97.5%) and day 30 (89%). Respective figures for group I were 27% and 27%. Independent factors for anemia at 1 month post‐transplant included: being male subject, treatment for hypertension at pretransplant, anemia at transplant, a higher mean corpuscular volume at transplant, and an induction therapy using antithymocyte globulins. Independent predictive factors for lower creatinine clearance included being female subjects, having a donor aged >50 years, being a recipient aged >50 years, not treated for hypertension at pretransplant, and no post‐transplant ESA therapy. High doses of ESA within the first month of kidney transplantation have no impact on anemia or renal function by 1 month post‐transplant.     

No evidence of occult hepatitis C virus (HCV) infection in serum of HCV antibody‐positive HCV RNA‐negative kidney‐transplant patients

Persistence of hepatitis C virus (HCV) in patients who cleared HCV is still debated. Occult HCV infection is described as the presence of detectable HCV RNA in liver or peripheral blood mononuclear cells (PBMCs) of patients with undetectable plasma HCV‐RNA by conventional PCR assays. We have assessed the persistence of HCV in 26 kidney‐transplant patients, followed up for 10.5 years (range 2–16), after HCV elimination while on hemodialysis. If HCV really did persist, arising out of the loss of immune control caused by institution of the regimen of immunosuppressive drugs after kidney transplantation, HCV reactivation would have taken place. Their immunosuppression relied on calcineurin inhibitors (100%), and/or steroids (62%), and/or antimetabolites (94%). An induction therapy, given to 22 patients, relied on rabbit antithymocyte globulin (59%) or anti‐IL2‐receptor blockers (32%). All patients had undetectable HCV RNA as ascertained by several conventional tests. At the last follow‐up, no residual HCV RNA was detected in the five liver biopsies, the 26 plasma, and in the 37 nonstimulated and 24 stimulated PBMCs tested with an ultrasensitive RT‐PCR assay (detection limit, 2 IU/ml). No biochemical or virologic relapse was seen during follow‐up. The absence of HCV relapse in formerly HCV‐infected immunocompromised patients suggests the complete eradication of HCV after its elimination while on dialysis.     

Pre‐emptive intravenous ganciclovir versus valganciclovir prophylaxis for de novo cytomegalovirus‐seropositive kidney‐transplant recipients

This sequential study evaluated two strategies regarding human cytomegalovirus (HCMV) infection/disease in HCMV‐seropositive de novo kidney‐transplant patients. The first cohort of patients (group 1; n = 132) was monitored sequentially for HCMV DNAemia; if it was positive (a cut‐off at 3 log₁₀copies/ml), the patient was given pre‐emptive IV ganciclovir therapy (10 mg/kg/day for 3 weeks). The second cohort consisted of 150 patients (group 2) who were given valganciclovir (VGC) prophylaxis (900 mg/day) for the first 3 months posttransplantation. During the mean follow‐up of at least 2 years for both cohorts, VGC prophylaxis resulted in a significant decrease in both CMV infection (68.9% vs. 33.3%; P < 0.001) and disease (9.8% vs. 2.68%, P = 0.021). Factors associated with HCMV reactivation in multivariate analysis were (i) no HCMV prophylaxis; (ii) recipient’s age; (iii) being placed on ciclosporine A and mycophenolic acid from the beginning of transplantation (iv) donor HCMV‐seropositivity; and (v) being a male recipient. No cases of ganciclovir resistance were detected in the prophylactic group. HCMV prophylaxis had no impact on 2‐year patient/graft survival or on kidney‐allograft function. We conclude that VGC‐prophylaxis can be reasonably used to treat HCMV‐seropositive kidney‐transplant recipients.     

Respiratory compensation and blood pH regulation during variable intensity exercise in trained versus untrained subjects

To determine whether endurance-trained cyclists (T; n = 10) have a superior blood-respiratory buffering for metabolic acidosis relative to untrained subjects (UT; n = 10) during variable intensity exercise (VAR). On three occasions, T and UT pedaled for 24 min alternating high- and low-intensities as percentage of their second ventilatory threshold (VT₂): VAR_LOW 87.5–37.5% VT₂, VAR_MODERATE 125–25% VT₂, and VAR_HIGH 162.5–12.5% VT₂ to complete the same amount of work. Before and just after each VAR trial, maximal cycling power (P_MAX) was assessed. For each trial, the respiratory compensation for exercise acidosis (ventilatory equivalent for CO₂) and the final blood pH, lactate and bicarbonate concentrations were similar for T and UT subjects. However, after VAR_HIGH, UT reduced P_MAX (−14 ± 1%; P < 0.05) while T did not. Our data suggest that endurance training confers adaptations to withstand the low pH provoked by VAR without losing cycling power, although this response is not due to differences in blood-respiratory buffering.     

Neurometabolic disorders and dysfunction in autism spectrum disorders

The cause of autism remains largely unknown because it is likely multifactorial, arising from the interaction of biologic, genetic, and environmental factors. The specific role of metabolic abnormalities also is largely unknown, but current research may provide insight into the pathophysiologic underpinnings of autism, at least in some patients. We review a number of known neurometabolic disorders identified as having an autistic phenotype. We also discuss the possible involvement of mitochondrial disorders and dysfunction as well as a theory regarding an increased vulnerability to oxidative stress, by which various environmental toxins produce metabolic alterations that impair normal cellular function. Finally, we review various strategies for metabolic work-up and treatment. Accurate diagnosis of neurometabolic disorders and a broader understanding of underlying metabolic disturbance even in the absence of known disease have important implications both for individual patients and for research into the etiology of autism.     

The effect of Nigella sativa alone, and in combination with dexamethasone, on tracheal muscle responsiveness and lung inflammation in sulfur mustard exposed guinea pigs

Ethnomedical relevance

The anti-inflammatory activity of both systemic and local administrations of essential oil from Nigella sativa L. has been shown.

Aim of the study

Therefore, the effect of Nigella sativa on tracheal responsiveness (TR) and lung inflammation of sulfur mustard (SM) exposed guinea pigs was examined.

Materials and methods

Guinea pigs were exposed to diluent solution (control group), inhaled SM (SME group), SME treated with Nigella sativa (SME + N), SME treated with dexamethasone (SME + D) and SME treated with both drugs (SME + N + D), (n = 7 for each group). TR to methacholine, total white blood cell (WBC) and differential WBC count of lung lavage, and serum cytokines were measured 14 days post-exposure.

Results

The values of TR, eosinophil, monocyte, lymphocyte, interleukine-4 (IL-4) and interferon gamma (IFN-γ) of SME group were significantly higher than those of controls (p < 0.05 to p < 0.001). The TR in SME + N, SME + D and SME + N + D was significantly lower compared to that of SME group (p < 0.01 for all cases). The percentage of eosinophil in SME + D, and the percentage of monocyte in SME + N + D (p < 0.05 to p < 0.01) were significantly lower than those in SME group. The neutrophil number was decreased in SME + N and SME + N + D groups compared to SME animals (p < 0.05 to p < 0.01). IL-4 levels in serum of SME + N (p < 0.01), SME + D (p < 0.05), SME + N + D (p < 0.01) and IFN-γ in SME + N (p < 0.05) were greater than those in SME animals.

Conclusions

These results showed a preventive effect of Nigella sativa on TR and lung inflammation of SM exposed guinea pigs.     

Inhibition of T-cell activation and proliferation by mycophenolic acid in patients awaiting liver transplantation: PK/PD relationships

Mycophenolic acid (MPA) plasma concentrations were reported to be associated with a decrease in T-cell proliferation, and in both IL-2 α-chain (CD25) and transferin receptor (CD71) expression. The aim of this study was to confirm, quantify and model these PK/PD relationships.Full profiles of MPA plasma concentrations, T-cell proliferation, intracytoplasmic IL-2 and TNF-α expression, and both CD71 and CD25 expression were collected over the 12 h after dosing in 10 patients on the waiting list for liver transplantation. Data were analyzed using NONMEM^®.Both CD25 and CD71 expression and T cell proliferation clearly decreased (median of decrease from baseline 62%, 68% and 94%, respectively) with increasing MPA concentrations, in contrast to IL-2 and TNF-α expression. The CD25 and CD71 baseline expression (E₀) and maximum effect (E_max) were correlated with the E₀ and E_max values of T-cell proliferation (r² = 0.509 and r² = 0.622, respectively). The CD25, CD71 expression and T-cell proliferation profiles were adequately fitted using a sigmoid inhibitory E_max model. Low estimated values (≤2 mg/L) for 50% inhibitory MPA concentrations were obtained. This study confirmed a transient MPA concentration-dependent decrease in T-cells expressing CD25 and CD71 and a strong reduction of T-cell proliferation and showed that CD25 and CD71 expression was correlated with T-cell proliferation.