Potts Anastomosis for Children with Idiopathic Pulmonary Hypertension

Mortality in children with idiopathic pulmonary arterial hypertension is high, emphasizing the need for novel therapeutic approaches. A surgical approach consisting in the creation of anastomosis between descending aorta and left pulmonary artery, the Potts shunt, has been proposed to decompress right ventricle. We reported two cases of severe idiopathic pulmonary hypertension in children with right heart failure refractory to medical treatment who benefited of Potts shunt.     

Full length MHC IIβ exon 2 primers for salmonids: a new resource for next generation sequencing

Major histocompatibility complex (MHC) genes are often implicated in disease resistance, sexual selection and local adaptation in salmonids, a highly studied and socio-economically important taxa. However, genotyping highly polymorphic genes is difficult, expensive, and prone to PCR and cloning artifacts that can result in false alleles. With the advent of next generation sequencing, it is possible to effectively “clone” PCR products in a massively parallel fashion with the use of individually-tagged fusion primers. Primers that amplify a gene of interest across a variety of taxa, a single set of 50–150 primers can facilitate cost efficient genotyping and become a common lab resource. Here we developed MHC IIβ exon 2 primers for full-length amplification, including an additional PBR region, and demonstrate effectiveness with representatives from five genera of salmonids. These primers may facilitate parallel next generation sequencing for efficient, cost effective, and accurate genotyping of this complex locus.     

Inhibition of the binding of HCV serum particles to human hepatocytes by E1E2‐specific D32.10 monoclonal antibody

The aim of this study was to determine the inhibition of binding activity of the monoclonal antibody (mAb) D32.10 which recognizes a highly conserved discontinuous antigenic determinant (E1:297–306, E2:480–494, and E2:613–621) expressed on the surface of serum‐derived HCV particles (HCVsp) of genotypes 1a, 1b, 2a, and 3a. To this end, an in vitro direct cell‐binding assay based on the attachment of radiolabeled HCVsp was developed, and Scatchard plots were used to analyze ligand–receptor binding data. HCV adsorption was also assessed by quantitating cell‐associated viral RNA by a real‐time RT‐PCR method. Saturable concentration‐dependent specific binding of HCVsp to Huh‐7 or HepaRG cells was demonstrated. The Scatchard transformed data showed two‐site interaction for Huh‐7 and proliferative HepaRG cells: the high‐affinity binding sites (K_d1 = 0.1–0.5 µg/ml) and the low‐affinity binding sites (K_d1 = 5–10 µg/ml), and one‐site high‐affinity binding model between E1E2/D32.10‐positive HCVsp and hepatocyte‐like differentiated HepaRG cells. The E1E2‐specific mAb D32.10 inhibited efficiently (>60%) and selectively the binding with an IC₅₀ ≤0.5 µg/ml in all the experimental approaches using serum HCV of genotype either 3 or 1b. This supports the involvement of the E1E2/D32.10 discontinuous antigenic determinant in the interactions between human hepatocytes and HCVsp, and suggests that D32.10‐like antibodies present in sera from patients infected with HCV could play a protective role. J. Med. Virol. 81:1726–1733, 2009. © 2009 Wiley‐Liss, Inc.     

Effect of chronic pre‐treatment with angiotensin converting enzyme inhibition on skeletal muscle mitochondrial recovery after ischemia/reperfusion

Impaired skeletal muscle energetic participates in peripheral arterial disease (PAD) patient’s morbidity and mortality. Angiotensin converting enzyme inhibition (ACEi), cornerstone for pharmacologic risk factor management in PAD patients, might also be interesting by protecting skeletal muscle energetic. We therefore determined whether chronic ACEi might reduce ischemia‐induced mitochondrial respiratory chain dysfunction in the frequent setting of hindlimb ischemia–reperfusion. Ischemic legs of rats submitted to 5 h ischemia induced by a rubber band tourniquet applied on the root of the hindlimb followed by reperfusion without (IR, n = 11) or after ACEi (n = 14; captopril 40 mg/kg per day during 28 days before surgery) were studied and compared to that of sham‐operated animals (n = 11). The effect of ACEi on the non‐ischemic contralateral leg was also determined in the ACEi group. Maximal oxidative capacities (V_max) and complexes I, II and IV activities of the mitochondrial respiratory chain of the gastrocnemius muscle were determined using glutamate–malate, succinate and TMPD–ascorbate substrates. Arterial blood pressure was significantly decreased after ACEi (124 ± 2.8 vs. 108 ± 4.19 mmHg; P = 0.01). Ischemia–reperfusion reduced V_max (4.4 ± 0.4 vs. 8.7 ± 0.5 μmol O₂/min/g dry weight, ?49%, P < 0.001), affecting mitochondrial complexes I, II and IV activities. ACEi failed to modulate ischemia‐induced dysfunction (V_max 5.1 ± 0.7 μmol O₂/min/g dry weight) or the non‐ischemic contralateral muscle respiratory rate. Ischemia–reperfusion significantly impaired the mitochondrial respiratory chain I, II and IV complexes of skeletal muscle. Pharmacologic pre‐treatment with ACEi did not prevent or increase such alterations. Further studies might be useful to improve the pharmacologic conditioning of PAD patients needing arterial revascularization.