Efficacy,safety, and immunosuppressant adherence in stable liver transplant patients converted from a twice‐daily tacrolimus‐based regimen to once‐daily tacrolimus extended‐release formulation

The aim of this study was to determine the efficacy, safety, and immunosuppressant adherence in 125 stable liver transplant (LT) patients converted from twice‐daily tacrolimus (TAC BID) to once‐daily TAC (TAC OD). Tacrolimus trough levels, laboratory parameters, metabolic disorders, selected patient reported outcomes, and adverse events were assessed. Mean TAC trough level concentration was 6.1 ± 2.3 ng/ml at study entry, decreased to 5.5 ± 2.1 ng/ml (P = 0.016) and 5.5 ± 2.2 ng/ml (P = 0.019) after 1 and 2 weeks, respectively, and tended to equal the baseline value during further follow‐up. At week 1, TAC concentrations were lower in 62.4% of patients and higher in 36.0% when compared with baseline. Renal and cardiovascular risk factors remained stable and no rejection episodes occurred over 12 months. Adverse events were consistent with the safety profile known from previous studies with TAC BID. Nonadherence measured by the “Basel Assessment of Adherence Scale to Immunosuppressives” was evident in 66.4% at study entry and decreased to 30.9% postconversion (P < 0.0001). Prevalence of nonadherence at baseline was significantly higher in patients converted >2 years after LT and in those ≤60 years of age. Conversion to TAC OD is safe, enhances immunosuppressant adherence and should be accompanied by a close TAC level monitoring during the initial period.     

Genetic risk score does not correlate with body mass index of Latina women in a clinical trial

Obesity disproportionately affects Latina women. Common genetic variants are convincingly associated with body mass index (BMI) and may be used to create genetic risk scores (GRS) for obesity that could define genetically influenced forms of obesity and alter response to clinical trial interventions. The objective of this study was (1) to identify the frequency and effect size of common obesity genetic variants in Latina women; (2) to determine the clinical utility of a GRS for obesity with Latina women participating in a community-based clinical trial. DNA from 85 Latina women was genotyped for eight genetic variants previously associated with BMI in Caucasians, but not yet assessed in Latina populations. The main outcome measure was the correlation of GRS (sum of eight risk alleles) with BMI, waist circumference, and percent body fat. A majority (83%) of participants had a BMI ≥25. Frequency of loci near FTO, MC4R, and GNPDA2 were lower in Latinas than Caucasians. Association of each locus with BMI was lower in Latinas compared to Caucasians with no significant correlations with BMI. We conclude that an eight locus GRS has no clinical utility for explaining obesity or predicting response to intervention in Latina women participating in a clinical trial.     

Oxidation of Z α1-antitrypsin by cigarette smoke induces polymerization: a novel mechanism of early-onset emphysema

The acceleration of chronic obstructive pulmonary disease (COPD) by cigarette smoke (CS) in individuals with severe genetic deficiency of α(1)-antitrypsin (Z-AT [Glu342Lys]) exemplifies the critical importance of gene-environmental interactions to the development of COPD. We investigated the molecular basis for the interaction between Z-AT and CS. Female mice (8-10 wk old) transgenic for normal (M-AT) or Z-AT on CBA background were exposed to four 1R3F cigarettes daily for 5 days. Age and sex matched littermates not exposed to CS were used as controls. Bronchoalveolar lavage fluid and lung homogenates were assessed for inflammatory cells, neutrophil elastase, and AT conformers. Z-AT was purified from plasma, exposed to CS extract, and assessed for the development and temporal relationship between AT conformers. Mice transgenic for Z-AT developed a significant increase in pulmonary polymers after acute CS exposure (P = 0.001). There were also increased neutrophils in CS-Z lungs versus controls (P < 0.001), which were tightly correlated with polymer concentrations (r(2) = 0.93). Oxidation of human plasma Z-AT by CS or N-chlorosuccinimide greatly accelerated polymerization (P = 0.004), which could be abrogated by antioxidants (P = 0.359 versus Z control). Our data show that CS accelerates polymerization of Z-AT by oxidative modification, which, in so doing, further reduces pulmonary defense and increases neutrophil influx into the lungs. These novel findings provide a molecular explanation for the striking observation of premature emphysema in ZZ homozygotes who smoke. Further work is required to assess whether antioxidant therapy may be beneficial in Z-AT-related COPD.     

A KCR1 variant implicated in susceptibility to the long QT syndrome

The acquired long QT syndrome (aLQTS) is frequently associated with extrinsic and intrinsic risk factors including therapeutic agents that inadvertently inhibit the KCNH2 K⁺ channel that underlies the repolarizing I_Kr current in the heart. Previous reports demonstrated that K⁺ channel regulator 1 (KCR1) diminishes KCNH2 drug sensitivity and may protect susceptible patients from developing aLQTS. Here, we describe a novel variant of KCR1 (E33D) isolated from a patient with ventricular fibrillation and significant QT prolongation. We recorded the KCNH2 current (I_KCNH2) from CHO-K1 cells transfected with KCNH2 plus wild type (WT) or mutant KCR1 cDNA, using whole cell patch-clamp techniques and assessed the development of I_KCNH2 inhibition in response to well-characterized KCNH2 inhibitors. Unlike KCR1 WT, the E33D variant did not protect KCNH2 from the effects of class I antiarrhythmic drugs such as quinidine or class III antiarrhythmic drugs including dofetilide and sotalol. The remaining current of the KCNH2 WT + KCR1 E33D channel after 100 pulses in the presence of each drug was similar to that of KCNH2 alone. Simulated conditions of hypokalemia (1 mM [K⁺]_o) produced no significant difference in the fraction of the current that was protected from dofetilide inhibition with KCR1 WT or E33D. The previously described α-glucosyltransferase activity of KCR1 was found to be compromised in KCR1 E33D in a yeast expression system. Our findings suggest that KCR1 genetic variations that diminish the ability of KCR1 to protect KCNH2 from inhibition by commonly used therapeutic agents constitute a risk factor for the aLQTS.     

Chronic migraine classification: current knowledge and future perspectives

In the field of so-called chronic daily headache, it is not easy for migraine that worsens progressively until it becomes daily or almost daily to find a precise and universally recognized place within the current international headache classification systems. In line with the 2006 revision of the second edition of the International Classification of Headache Disorders (ICHD-2R), the current prevailing opinion is that this headache type should be named chronic migraine (CM) and be characterized by the presence of at least 15 days of headache per month for at least 3 consecutive months, with headache having the same clinical features of migraine without aura for at least 8 of those 15 days. Based on much evidence, though, a CM with the above characteristics appears to be a heterogeneous entity and the obvious risk is that its definition may be extended to include a variety of different clinical entities. A proposal is advanced to consider CM a subtype of migraine without aura that is characterized by a high frequency of attacks (10–20 days of headache per month for at least 3 months) and is distinct from transformed migraine (TM), which in turn should be included in the classification as a complication of migraine. Therefore, CM should be removed from its current coding position in the ICHD-2 and be replaced by TM, which has more restrictive diagnostic criteria (at least 20 days of headache per month for at least 1 year, with no more than 5 consecutive days free of symptoms; same clinical features of migraine without aura for at least 10 of those 20 days).     

Early human pregnancy serum cytokine levels predict autoimmunity in offspring

It is generally believed that pregnancy is mediated by a Th2 response, which includes cytokines that promote placental growth and are involved in inducing tolerance to the foetus. If the balance between Th1/and Th2-mediated cytokines is disrupted, systemic and local changes could predispose the foetus to future disease. Therefore, a shift in the Th1/Th2 balance during pregnancy, possibly caused by underlying environmental factors, could be associated with post-partum autoimmune disease in the offspring. Based on this presumption, we used celiac disease as a model to investigate whether autoimmunity is triggered in the foetus during early pregnancy, observed as changes in the mother's cytokine profile. Ten cytokines were measured by electro-chemi-luminescent multiplex ELISA in serum samples obtained from mothers during early pregnancy. Cases included women with children who had developed verified celiac disease before the age of 5, who were compared with other women as matched controls. We observed that 7 out of 10 cytokine levels were significantly increased in our case mothers when compared to controls. Five of these belonged to what is generally known as a Th1-mediated response (TNFα, IFNγ, IL-2, IL-1β and IL-12) and two were Th2 cytokines (IL-13 and IL-10). However, the IL-10 cytokine is known to have features from both arms of the immune system. These results were confirmed in a logistic regression model where five out of the initial seven cytokines remained. This study suggests that increase in Th1 serum cytokines may be associated with celiac disease in offspring.     

Pulmonary response to surface-coated nanotitanium dioxide particles includes induction of acute phase response genes, inflammatory cascades, and changes in microRNAs: a toxicogenomic study

Titanium dioxide nanoparticles (nanoTiO(2) ) are used in various applications including in paints. NanoTiO(2) inhalation may induce pulmonary toxicity and systemic effects. However, the underlying molecular mechanisms are poorly understood. In this study, the effects of inhaled surface-coated nanoTiO(2) on pulmonary global messenger RNA (mRNA) and microRNA (miRNA) expression in mouse were characterized to provide insight into the molecular response. Female C57BL/6BomTac mice were exposed for 1 hr daily to 42.4 ± 2.9 (SEM) mg surface-coated nanoTiO(2) /m(3) for 11 consecutive days by inhalation and were sacrificed 5 days following the last exposure. Physicochemical properties of the particles were determined. Pulmonary response to nanoTiO(2) was characterized using DNA microarrays and pathway-specific PCR arrays and related to data on pulmonary inflammation from bronchial lavages. NanoTiO(2) exposure resulted in increased levels of mRNA for acute phase markers serum amyloid A-1 (Saa1) and serum amyloid A-3 (Saa3), several C-X-C and C-C motif chemokines, and cytokine tumor necrosis factor genes. Protein analysis of Saa1 and 3 showed selective upregulation of Saa3 in lung tissues. Sixteen miRNAs were induced by more than 1.2-fold (adjusted P-value < 0.05) following exposure. Real time polymerase chain reaction confirmed the upregulation of miR-1, miR-449a and revealed dramatic induction of miR-135b (60-fold). Thus, inhalation of surface-coated nanoTiO(2) results in changes in the expression of genes associated with acute phase, inflammation and immune response 5 days post exposure with concomitant changes in several miRNAs. The role of these miRNAs in pulmonary response to inhaled particles is unknown and warrants further research.