Increased mitochondrial uncoupling proteins, respiratory uncoupling and decreased efficiency in the chronically infarcted rat heart

Heart failure patients have abnormal cardiac high energy phosphate metabolism, the explanation for which is unknown. Patients with heart failure also have elevated plasma free fatty acid (FFA) concentrations. Elevated FFA levels are associated with increased cardiac mitochondrial uncoupling proteins (UCPs), which, in turn, are associated with decreased mitochondrial respiratory coupling and low cardiac efficiency. Here, we determined whether increased mitochondrial UCP levels contribute to decreased energetics in the failing heart by measuring UCPs and respiration in mitochondria isolated from the viable myocardium of chronically infarcted rat hearts and measuring efficiency (hydraulic work/O₂ consumption) in the isolated, working rat heart. Ten weeks after infarction, cardiac levels of UCP3 were increased by 53% in infarcted, failing hearts that had ejection fractions less than 45%. Cardiac UCP3 levels correlated positively with non-fasting plasma FFAs (r = 0.81; p < 0.01). Mitochondria from failing hearts were less coupled than those from control hearts, as demonstrated by the lower ADP/O ratio of 1.9 ± 0.1 compared with 2.5 ± 0.2 in controls (p < 0.05). The decreased ADP/O ratio was reflected in an efficiency of 14 ± 2% in the failing hearts when perfused with 1 mM palmitate, compared with 20 ± 1% in controls (p < 0.05). We conclude that failing hearts have increased UCP3 levels that are associated with high circulating FFA concentrations, mitochondrial uncoupling, and decreased cardiac efficiency. Thus, respiratory uncoupling may underlie the abnormal energetics and low efficiency in the failing heart, although whether this is maladaptive or adaptive would require direct investigation.     

Detection of high frequencies of HIV-1 cross-subtype reactive CD8 T lymphocytes in the peripheral blood of HIV-1-infected Kenyans

OBJECTIVES: To quantitate rapidly the frequency of HIV-1 subtype-specific and broadly HIV-1 cross-subtype-reactive CD8 T cells in the peripheral blood of HIV-1-infected individuals from a geographical region of multiple subtype endemicity. METHODS: Autologous B-lymphoblastoid cell lines infected with recombinant vaccinia-viruses expressing gag, env and nef gene products from HIV-1 subtypes A-H were used as antigen-presenting cells to stimulate CD8 T cells from cryopreserved peripheral blood mononuclear cells. Cross-subtype and subtype-specific CD8 cell responses were assessed by flow cytometry for the upregulation of IFN-gamma gene expression in specifically activated CD8 T cells. RESULTS: Strikingly high frequencies of circulating CD8 T cells (up to 11.3% of peripheral CD8 T cells) with specificity for HIV-1 were detectable using this methodology. Both subtype-specific and broadly cross-subtype-reactive CD8 T cells were detected as assessed by IFN-gamma production after stimulation. The pattern of cross-subtype reactivity appeared to be random when the results were assessed as a population, but analysis of the full-length sequence of the infecting virus for each individual showed some skewing of the CD8 cell response towards the infecting subtype. CONCLUSION: High frequencies of HIV-1 cross-subtype-reactive peripheral CD8 T cells can be detected in individuals from a multiple subtype endemic region, providing an incentive for vaccine advancement in such locations. The future assessment of the subtype specificity of cellular immune responses requires full-length sequencing of the infecting virus in conjunction with a comprehensive analysis of phenotypic and functional parameters.     

Advances in pharmacotherapy for the treatment of allergic rhinitis; MP29-02 (a novel formulation of azelastine hydrochloride and fluticasone propionate in an advanced delivery system) fills the gaps

Introduction: Effective pharmacologic treatment exists for most patients suffering from allergic rhinitis (AR). However, both in clinical trials and in real-life studies, many patients are dissatisfied with treatment. Physicians often use multiple therapies, in an attempt to improve symptom control, often with limited evidence of success. Novel treatment options are needed and must consider unmet medical needs.

Areas covered: This article reviews the clinical data for a new AR treatment. MP29-02 (Dymista®, Meda, Solna, Sweden) contains azelastine hydrochloride (AZE) and fluticasone propionate (FP), in a novel formulation and delivered in an improved device as a single nasal spray. It has shown superior efficacy in AR patients than either commercially available AZE or FP monotherapy for both nasal and ocular symptom relief, regardless of disease severity. MP29-02 also provided more effective and rapid symptom relief than either AZE or FP monotherapy delivered in the MP29-02 formulation and device. However, the effect was less than that observed versus commercial comparators, suggesting the impact of formulation and device on clinical efficacy.

Expert opinion: MP29-02 simplifies AR management, surpassing the efficacy of gold standard treatment, intranasal corticosteroids (INS), for the first time. It is indicated for the treatment of moderate-to-severe seasonal allergic rhinitis and perennial allergic rhinitis when monotherapy with either intranasal antihistamine or INS is NOT considered sufficient. Most patients present with moderate/severe disease, with evidence of current or previous treatment insufficiency. MP29-02 should be the treatment of choice for these patients.     

A large nontypical outbreak of Norwalk virus. Gastroenteritis associated with exposing celery to nonpotable water and with Citrobacter freundii.

The US Air Force Academy experienced a point-source outbreak of gastroenteritis originally believed to be caused by Salmonella. The overall attack rate was 48% among approximately 3000 cadets and staff. Food-specific attack rates implicated chicken salad. The odds ratio for chicken salad consumption in ill cadets was 10.7 (95% confidence interval: 8.2; 13.8). The celery component had been exposed to nonpotable water. Citrobacter freundii were statistically associated with consumption of the suspected vehicle and subsequent illness. Most aspects were consistent with the epidemiology of Norwalk gastroenteritis. However, the clinical presentation was not typical of reported outbreaks. One hundred five cadets required intravenous rehydration. Serum samples implicated Norwalk virus as the most probable cause of this outbreak. The Centers for Disease Control (Atlanta, Ga) recently began national surveillance for viral gastroenteritis. All outbreaks of gastroenteritis associated with nonpotable water should be investigated for evidence of viral cause.     

Clinical significant of serum chromogranin A levels for diagnosing pheochromocytoma in hypertensive patients

OBJECTIVE: CMA is a widespread glycoprotein located in the secretory vesicles of neuroendocrine cells and is co-released with peptides and biogenic amines into the circulation. The present study set out to investigate the clinical utility of assessing serum CGA levels in comparison with the urinary KTCO and their urinary metabolites concentrations, which are to date the gold standard validated diagnostic test. METHODS: From January 2000 to June 2001, 202 consecutive patients, aged 53 +/- 12.7, 102 males, were admitted to our department for a hypertension evaluation. Blood samples for measurements of plasma concentrations of chromogranin A were collected and serum CGA levels were quantified by RIA technique (RIACT). This radioimmunometric technique consisted in using 2 monoclonal antibodies directed to 2 specific antigenic domains of the middle portion of the CGA. The fixed threshold value for identifying positive results was, set at 100 ng/ml according to previous studies. RESULTS: No pheochomocytoma was diagnosed by conventional urinary KTCO essay. Of the 202 CGA blood samples, 32 turned out to be positive, due to commonly encountered false positive causes (inhibitor of the pump with protons, corticotherapy, hypergastrinemia, chronic renal insufficiency, respectively, in 11, 2, 1, 18 cases). The CGA plasma concentration averaged 77 +/- 77 mg/ml and 203 +/- 125 ng/ml in the CGA subgroup over the threshold value. CONCLUSION: The reliability of immunoradiometric serum CGA concentrations appeared according to this work to be comparable to that of the urinary KTCO levels and their urinary metabolites in hypertensives. Moreover, it solely requires a simple, easily done blood taking, less expensive than urinary KTCO collection. Besides, no antihypertensive drugs interfered with the analysis of CGA levels. However, some false positive results have to be mentioned in the presence of renal impairment, hypergastrinemia, corticotherapy, inhibitor of the pump with protons.     

Alteration in the laboratory profile of a lupus anticoagulant in a patient with non-Hodgkin's lymphoma

We describe a patient with non-Hodgkin's lymphoma who developed a lupus anticoagulant (LA) detectable by activated partial thromboplastin time (APTT), dilute Russell's viper venom time (DRVVT) and kaolin clotting time (KCT). IgM anticardiolipin antibodies (ACA) were elevated. At a later admission, and following treatment for the lymphoma, routine coagulation screening showed an elevated prothrombin time (PT) without correction in mixing tests using a recombinant thromboplastin. Routine APTT was below the reference range and ACA levels were normal. Raw data for one-stage factor assays demonstrated the presence of an inhibitor. Analysis for LA was undertaken by DRVVT, KCT, activated seven lupus anticoagulant assay, Taipan snake venom time, platelet neutralisation procedures (PNP), Ecarin time and PT using rabbit brain thromboplastin. The results revealed a LA capable of prolonging the clotting times of the PNPs and PT using recombinant thromboplastin, but that was corrected using Ecarin venom, modified PNP and brain thromboplastin. The antibody also demonstrated the lupus anticoagulant co-factor effect. The factor VIII: C was markedly raised which may have masked the LA in the APTT. The changing laboratory profile over time demonstrates the effects of LA heterogeneity and variations in sensitivity and specificity of assays for the detection of antiphospholipid antibodies.     

Rapid Detection of Rare Deleterious Variants by Next Generation Sequencing with Optional Microarray SNP Genotype Data

Autozygosity mapping is a powerful technique for the identification of rare, autosomal recessive, disease‐causing genes. The ease with which this category of disease gene can be identified has greatly increased through the availability of genome‐wide SNP genotyping microarrays and subsequently of exome sequencing. Although these methods have simplified the generation of experimental data, its analysis, particularly when disparate data types must be integrated, remains time consuming. Moreover, the huge volume of sequence variant data generated from next generation sequencing experiments opens up the possibility of using these data instead of microarray genotype data to identify disease loci. To allow these two types of data to be used in an integrated fashion, we have developed AgileVCFMapper, a program that performs both the mapping of disease loci by SNP genotyping and the analysis of potentially deleterious variants using exome sequence variant data, in a single step. This method does not require microarray SNP genotype data, although analysis with a combination of microarray and exome genotype data enables more precise delineation of disease loci, due to superior marker density and distribution.     

Measuring Emergency Care Survival: The Implications of Risk Adjusting for Race and Poverty

Objectives

We determined the impact of including race, ethnicity, and poverty in risk adjustment models for emergency care–sensitive conditions mortality that could be used for hospital pay‐for‐performance initiatives. We hypothesized that adjusting for race, ethnicity, and poverty would bolster rankings for hospitals that cared for a disproportionate share of nonwhite, Hispanic, or poor patients.

Methods

We performed a cross‐sectional analysis of patients admitted from the emergency department to 157 hospitals in Pennsylvania with trauma, sepsis, stroke, cardiac arrest, and ST‐elevation myocardial infarction. We used multivariable logistic regression models to predict in‐hospital mortality. We determined the predictive accuracy of adding patient race and ethnicity (dichotomized as non‐Hispanic white vs. all other Hispanic or nonwhite patients) and poverty (uninsured, on Medicaid, or lowest income quartile zip code vs. all others) to other patient‐level covariates. We then ranked each hospital on observed‐to‐expected mortality, with and without race, ethnicity, and poverty in the model, and examined characteristics of hospitals with large changes between models.

Results

The overall mortality rate among 170,750 inpatients was 6.9%. Mortality was significantly higher for nonwhite and Hispanic patients (adjusted odds ratio [aOR] = 1.27, 95% confidence interval [CI] = 1.19–1.36) and poor patients (aOR = 1.21, 95% CI = 1.12–1.31). Adding race, ethnicity, and poverty to the risk adjustment model resulted in a small increase in C‐statistic (0.8260 to 0.8265, p = 0.002). No hospitals moved into or out of the highest‐performing decile when adjustment for race, ethnicity, and poverty was added, but the three hospitals that moved out of the lowest‐performing decile, relative to other hospitals, had significantly more nonwhite and Hispanic patients (68% vs. 11%, p < 0.001) and poor patients (56% vs. 10%, p < 0.001).

Conclusions

Sociodemographic risk adjustment of emergency care–sensitive mortality improves apparent performance of some hospitals treating a large number of nonwhite, Hispanic, or poor patients. This may help these hospitals avoid financial penalties in pay‐for‐performance programs.