Searching for Preclinical Models of Acute Decompensated Heart Failure: a Concise Narrative Overview and a Novel Swine Model

Cardiovascular Drugs and Therapy - Available animal models of acute heart failure (AHF) and their limitations are discussed herein. A novel and preclinically relevant porcine model of decompensated...     

Identification of new mutations of the HFE, hepcidin, and transferrin receptor 2 genes by denaturing HPLC analysis of individuals with biochemical indications of iron overload

BACKGROUND: Hereditary hemochromatosis is a recessive disorder characterized by iron accumulation in parenchymal cells, followed by organ damage and failure. The disorder is mainly attributable to the C282Y and H63D mutations in the HFE gene, but additional mutations in the HFE, transferrin receptor 2 (TfR2), and hepcidin genes have been reported. The copresence of mutations in different genes may explain the phenotypic heterogeneity of the disorder and its variable penetrance. METHODS: We used denaturing HPLC (DHPLC) for rapid DNA scanning of the HFE (exons 2, 3, and 4), hepcidin, and TfR2 (exons 2, 4 and 6) genes in a cohort of 657 individuals with altered indicators of iron status. RESULTS: DHPLC identification of C282Y and H63D HFE alleles was in perfect agreement with the restriction endonuclease assay. Fourteen DNA samples were heterozygous for the HFE S65C mutation. In addition, we found novel mutations: two in HFE (R66C in exon 2 and R224G in exon 4), one in the hepcidin gene (G71D), and one in TfR2 (V22I), plus several intronic or silent substitutions. Six of the seven individuals with hepcidin or TfR2 coding mutations carried also HFE C282Y or S65C mutations. CONCLUSION: DHPLC is an efficient method for mutational screening for the genes involved in hereditary hemochromatosis and for the study of their copresence.     

Use of a reference standard to improve the accuracy and precision of seven kits for determination of ferritin in serum

We assessed the accuracy and precision of seven commercial kits for serum ferritin. The concentration of ferritin as determined by these assays for a liver ferritin reference standard, a human heart ferritin standard, and normal sera correlated highly, but the absolute values varied widely. Use of an international reference standard for ferritin to prepare the standard curve greatly diminished the variability, but did not eliminate it. Although the seven kits differed in specificity for various human isoferritins, this did not appear substantially to affect accuracy. Six of the seven kits appeared sufficiently precise for clinical use over a wide range of ferritin concentrations.     

HE4 and epithelial ovarian cancer: comparison and clinical evaluation of two immunoassays and a combination algorithm

BackgroundTwo commercial immunoassays for HE4 have been compared and the diagnostic accuracy of HE4, CA 125 and the combinatory ROMA algorithm for epithelial ovarian cancer (EOC) has been evaluated.MethodsHE4 and CA125 were measured on sera obtained from 259 women (73 healthy, 90 with benign ovarian or adnexal diseases, 96 with EOC). The ARCHITECT CMIA HE4 assay was compared with the Fujirebio EIA HE4, and the risk for EOC by the combinatory ROMA algorithm (HE4 + CA 125) was assessed with both HE4 assays.ResultsThe CMIA HE4 assay showed a good linearity (r > 0.9998) and precision (interassay and total CVs < 4%). The correlation with EIA HE4 was linear (r = 0.994), with an average bias of 0.4%. By ROC curve analysis, the sensitivity for EOC at a fixed specificity of 90%, 95% and 99% was 89.6%, 84.4% and 79.2% by CMIA HE4, 84.4%, 83.3% and 79.2% by EIA HE4, 86.5%, 76.0% and 59.4% by CMIA CA125. The accuracy of the ROMA algorithm determined by CMIA or EIA HE4 was very similar (AUC 87.1% vs. 87.6%; p = n.s.) and greater in menopause.ConclusionsThe two HE4 assays showed a good correlation and similar clinical value, with a greater precision for CMIA. HE4 was more specific and accurate than CA125, supporting its use in addition to clinical and imaging criteria for the discrimination of benign from malignant ovarian lesions. The ROMA algorithm showed a good accuracy for discriminating women at high risk for EOC.     

Regional Differences in Cerebral Glucose Metabolism After Cardiac Arrest and Resuscitation in Rats Using [<Superscript>18</Superscript>F]FDG Positron Emission Tomography and Autoradiography

Background

Cardiac arrest is an important cause of morbidity and mortality. Brain injury severity and prognosis of cardiac arrest patients are related to the cerebral areas affected. To this aim, we evaluated the variability and the distribution of brain glucose metabolism after cardiac arrest and resuscitation in an adult rat model.

Methods

Ten rats underwent 8-min cardiac arrest, induced with a mixture of potassium and esmolol, and resuscitation, performed with chest compressions and epinephrine. Eight sham animals received anesthesia and experimental procedures identical to the ischemic group except cardiac arrest induction. Brain metabolism was assessed using [¹⁸F]FDG autoradiography and small animal-dedicated positron emission tomography.

Results

The absolute glucose metabolism measured with [¹⁸F]FDG autoradiography 2 h after cardiac arrest and resuscitation was lower in the frontal, parietal, occipital, and temporal cortices of cardiac arrest animals, showing, respectively, a 36% (p = 0.006), 32% (p = 0.016), 36% (p = 0.009), and 32% (p = 0.013) decrease compared to sham group. Striatum, hippocampus, thalamus, brainstem, and cerebellum showed no significant changes. Relative regional metabolism indicated a redistribution of metabolism from cortical area to brainstem and cerebellum.

Conclusions

Our data suggest that cerebral regions have different susceptibility to moderate global ischemia in terms of glucose metabolism. The neocortex showed a higher sensibility to hypoxia–ischemia than other regions. Other subcortical regions, in particular brainstem and cerebellum, showed no significant change compared to non-ischemic rats.

     

Comparison of scintigraphy with indium-111 leukocyte scan and ultrasonography in assessment of x-ray-demonstrated lesions of crohn's disease

The aim of this study was to compare the results obtained with an indium-111 scan with those obtained with less expensive and harmless ultrasonography to evaluate the location and inflammatory activity of Crohn's disease. Thirty-one patients previously studied with x-ray underwent abdominal¹¹¹In scans and ultrasonography (US). Sensitivity and specificity of US in detecting lesions seen with¹¹¹In scan were 77% and 92.8%, respectively. Sensitivity and specificity of¹¹¹In scan in detecting x-ray-defined lesions were 69.2% and 92.7%; the figures for US were 73% and 93.3%, respectively. Considering the evaluation of disease activity, ultrasonographic bowel wall thickness was significantly related to scintigraphic intensity of emission (r=0.75 P<0.01). Our experience suggests that US provided information about the location and inflammatory activity of lesions similar to that obtained from¹¹¹In scan.     

Investigations on the stereoselective action of isoxsuprine on alpha- and beta-adrenoceptors in equine common digital artery.

The affinity and functional effects of isoxsuprine enantiomers were investigated to determine the enantiospecificity of the beta-agonistic and alpha-blocking effects. Functional assays on isolated smooth muscle preparations from equine common digital artery were performed to determine the apparent affinity (pD(2)) and intrinsic activity (alpha(E)) of (-)erythro-isoxsuprine (alphaS, betaR, gammaR) and (+)erythro-isoxsuprine (alphaR, betaS, gammaS). The affinity of two enantiomers for the different adrenoceptor types was studied by radioligand binding assays on membrane preparations from the same tissue, using (-)[(3)H]CGP12177 and [(3)H]prazosin. On noradrenaline-precontracted artery preparations (-)isoxsuprine was markedly more potent than (+)isoxsuprine in dilating preparations, indicating that the laevorotatory enantiomer has a very high apparent affinity for alpha-adrenoceptors. Binding studies confirmed that (-)isoxsuprine has a higher affinity than (+)isoxsuprine for alpha-adrenoceptors, while the (+) isomer competes for beta-adrenoceptors with an affinity similar to that of propranolol. As described for other beta-phenylethylamines, the two isoxsuprine enantiomers studied have different efficacies for alpha- and beta-adrenoceptors and the effects of the commercially available mixture of stereoisomers therefore depend on the density and functional importance of the adrenoceptor types present in the tissue studied. 1999 Academic Press.     

Effects of new fish oil derivative on fatty acid phospholipid-membrane pattern in a group of Crohn's disease patients

Fish oil has been recently proposed as a possible effective treatment in inflammatory bowel disease (IBD); however, a lot of annoying side effects (ie, belching, halitosis, diarrhea, etc) affect patient compliance. We carried out a study of patient tolerance in a group of Crohn's disease (CD) patients with a new fish oil derivative consisting of 500-mg capsules of eicosapentaenoic-docosahexaenoic (EPA 40%-DHA 20%), a free fatty acid mixture (Purepa), and we also evaluated its incorporation into phospholipids, both in plasma and in red cell membranes. Five groups of 10 CD patients in remission received nine Purepa capsules daily in four different preparations (A: uncoated, B: coated, pH 5.5; C: coated, pH 5.5, 60 min time release; D: coated, pH 6.9) and 12 × 1-g capsules daily of a triglyceride preparation (Max-EPA, EPA 18%-DHA 10%), respectively. We coated three of the four Purepa preparations in order to delay the release of contents in an attempt to minimize the side effects. After six weeks of treatment, the group taking Purepa capsules, coated, pH 5.5, 60 min time release (group C) showed the best incorporation of EPA and DHA in red blood cell phospholipid membranes (EPA from 0.2 to 4.4%, DHA from 3.7 to 6.3%), and no side effects were registered, whereas in all other groups side effects were experienced in 50% or more of subjects. This new preparation will make it possible to treat patients for long periods.