Increased oxidative stress and severe arterial remodeling induced by permanent high-flow challenge in experimental pulmonary hypertension

Atopic asthma is a chronic inflammatory pulmonary disease characterised by recurrent episodes of wheezy, laboured breathing with an underlying Th2 cell-mediated inflammatory response in the airways. It is currently treated and, more or less, controlled depending on severity, with bronchodilators e.g. long-acting beta agonists and long-acting muscarinic antagonists or anti-inflammatory drugs such as corticosteroids (inhaled or oral), leukotriene modifiers, theophyline and anti-IgE therapy. Unfortunately, none of these treatments are curative and some asthmatic patients do not respond to intense anti-inflammatory therapies. Additionally, the use of long-term oral steroids has many undesired side effects. For this reason, novel and more effective drugs are needed. In this review, we focus on the CD4+ Th2 cells and their products as targets for the development of new drugs to add to the current armamentarium as adjuncts or as potential stand-alone treatments for allergic asthma. We argue that in early disease, the reduction or elimination of allergen-specific Th2 cells will reduce the consequences of repeated allergic inflammatory responses such as lung remodelling without causing generalised immunosuppression.     

A Cyclophilin Homology Domain-Independent Role for Nup358 in HIV-1 Infection

The large nucleoporin Nup358/RanBP2 forms eight filaments that project from the nuclear pore into the cytoplasm where they function as docking platforms for nucleocytoplasmic transport receptors. RNAi screens have implicated Nup358 in the HIV-1 life cycle. The 164 C-terminal amino acids of this 3,224 amino acid protein are a cyclophilin homology domain (Nup358Cyp), which has potential to bind the HIV-1 capsid and regulate viral progress to integration. Here we examined the virological role of Nup358 in conditional knockout mouse cells and in RNAi-depleted human CD4+ T cells. Cre-mediated gene knockout was toxic and diminished HIV-1 infectivity. However, cellular health and HIV-1 susceptibility were coordinately preserved if, prior to gene inactivation, a transposon was used to express all of Nup358 or only the N-terminal 1340 amino acids that contain three FG repeats and a Ran-binding domain. HIV-1, but not N74D capsid-mutant HIV-1, was markedly sensitive to TNPO3 depletion, but they infected 1–1340 segment-complemented Nup358 knockout cells equivalently. Human and mouse CypA both rescued HIV-1 in CypA gene −/− Jurkat cells and TRIM-Nup358Cyp fusions derived from each species were equally antiviral; each also inhibited both WT and N74D virus. In the human CD4+ T cell line SupT1, abrupt Nup358 depletion reduced viral replication but stable Nup358-depleted cells replicated HIV-1 normally. Thus, human CD4+ T cells can accommodate to loss of Nup358 and preserve HIV-1 susceptibility. Experiments with cylosporine, viruses with capsids that do not bind cyclophilins, and growth arrest did not uncover viral dependency on the C-terminal domains of Nup358. Our data reinforce the virological importance of TNPO3 and show that Nup358 supports nuclear transport functions important for cellular homeostasis and for HIV-1 nuclear import. However, the results do not suggest direct roles for the Nup358 cyclophilin or SUMO E3 ligase domains in engaging the HIV-1 capsid prior to nuclear translocation.     

Serum netrin and VCAM-1 as biomarker for Egyptian patients with type IΙ diabetes mellitus

ObjectiveThis study aimed to evaluate the serum level of netrin and soluble vascular cell adhesion molecule 1 (VCAM-I) in patients with type IΙ diabetes mellitus (T2DM) and evaluate the association of their levels with the development of a diabetic complication.Patients and methodsThis study was carried out on type II diabetic patients with and without complications and healthy individuals served as controls. All subjects were submitted to the estimation of serum lipid profile, serum creatinine, urinary albumin/creatinine ratio (ACR), fasting blood glucose (FBG), glycated hemoglobin (HbA1c), visceral adiposity index (VAI), atherogenic index of plasma (AIP), lipid accumulation product (LAP) and detection of serum level of netrin1 and VCAM1.ResultsDiabetic patients with complications had significantly higher serum levels of creatinine, ACR, cholesterol, Triglyceride, low-density lipoprotein, netrin1, and VCAM1 than diabetic patients without complications. Likewise, the level of VAI and LAP as markers of excessive body fat were significantly higher in diabetic patients with complications than diabetic patients without complications. The netrin1 and VCAM1 were a significant discriminator of T2DM renal complications with a sensitivity of 96%, 90%, and specificity of 82.7%, 91.3% respectively.ConclusionIt can be concluded that serum netrin1 and VCAM1 correlated significantly with markers of excessive body fat, a renal complication in the patient with type 2 diabetes mellitus.     

Preliminary cryocrystallography analysis of an eumenine mastoparan toxin isolated from the venom of the wasp Anterhynchium flavomarginatum micado

Mastoparans are tetradecapeptides found to be the major component of vespid venoms. These peptides present a wide spectrum of biological activities, such as mast cell degranulation, hemolytic activity and also reveals antimicrobial activity. A mastoparan toxin isolated from the venom of Anterhynchium flavomarginatum micado has been crystallized. At room temperature these crystals diffracted to 2.8 A resolution. However, upon cooling to cryogenic temperature around 85 K, the original resolution limit could be improved to 2.0 A. Crystals were determined to belong to the space group P3(1) (P3(2)). This is the first mastoparan to be crystallized and it will provide further insights in the conformational significance of mastoparan toxins, with respect to their potency and activity in G protein regulation.     

Arterial baroreflex control of sympathetic nerve activity during acute hypotension: effect of fitness

We examined arterial baroreflex control of muscle sympathetic nerve activity (MSNA) during abrupt decreases in mean arterial pressure (MAP) and evaluated whether endurance training alters baroreflex function. Acute hypotension was induced nonpharmacologically in 14 healthy subjects, of which 7 were of high fitness (HF) and 7 were of average fitness (AF), by releasing a unilateral arterial thigh cuff after 9 min of resting ischemia under two conditions: control, which used aortic and carotid baroreflex (ABR and CBR, respectively) deactivation; and suction, which used ABR deactivation alone. The application of neck suction to counteract changes in carotid sinus transmural pressure during cuff release significantly attenuated the MSNA response (which increased 134 +/- 32 U/14 s) compared with control (which increased 195 +/- 43 U/14 s) and caused a greater decrease in MAP (19 +/- 2 vs. 15 +/- 2 mmHg; P < 0.05). Furthermore, during both trials, the HF subjects exhibited a greater decrease in MAP compared with AF subjects despite an augmented baroreflex control of MSNA. These data indicate that the CBR contributes importantly to the MSNA response during acute systemic hypotension. Additionally, we suggest that an impaired control of vascular reactivity hinders blood pressure regulation in HF subjects.     

Neurotensin: dual roles in psychostimulant and antipsychotic drug responses

Central administration of neurotensin (NT) results in a variety of neurobehavioral effects which, depending upon the administration site, resemble the effects of antipsychotic drugs (APDs) and psychostimulants. All clinically effective APDs exhibit significant affinities for dopamine D(2) receptors, supporting the hypothesis that an increase in dopaminergic tone contributes to schizophrenic symptoms. Psychostimulants increase extracellular dopamine (DA) levels and chronics administration can produce psychotic symptoms over time. APDs and psychostimulants induce Fos and NT expression in distinct striatal subregions, suggesting that changes in gene expression underlie some of their effects. To gain insight into the functions of NT, we analyzed APD and psychostimulant induction of Fos in NT knockout mice and rats pretreated with the NT antagonist SR 48692. In both NT knockout mice and rats pretreated with SR 48692, haloperidol-induced Fos expression was markedly attenuated in the dorsolateral striatum; amphetamine-induced Fos expression was reduced in the medial striatum. These results indicate that NT is required for the activation of specific subpopulations of striatal neurons in distinct striatal subregions in response to both APDs and psychostimulants. This review integrates these new findings with previous evidence implicating NT in both APD and psychostimulant responses.     

Adenosine and its nucleotides activate wild-type and R117H CFTR through an A2B receptor-coupled pathway

ATP and itsmetabolites stimulate Clsecretion in human epithelium in vitro and in vivo. The specificpurinergic receptor subtypes that govern these effects have beendifficult to separate, in part due to multiple parallel pathways forCl secretion in respiratoryand intestinal epithelia. In a simplified model using COS-7 cells, wedemonstrate acquisition of an ATP-, ADP-, AMP-, and adenosine(ADO)-regulated halide permeability specifically following expressionof wild-type (wt) cystic fibrosis transmembrane conductance regulator(CFTR). This halide permeability is blocked by theP₁ purinergic receptor antagonist8-phenyl theophylline, sensitive to the protein kinase A inhibitorH-89, and associated with a modest, dose-dependent increase in cellularcAMP concentration. Phorbol esters poorly activate halide permeabilitycompared with ADO, and ADO-stimulated efflux was not affected bytreatment with the protein kinase C inhibitor bisindolylmaleimide I. The A₂ ADO receptor (AR) agonists5'-N-ethylcarboxamide adenosineand ADO were strong activators, whereas theA₁ AR agonistR-phenylisopropyladenosine failed toactivate halide permeability. Metabolic conversion of ADO nucleotidesby surface ecto-5'-nucleotidase to more active (lessphosphorylated) forms contributes to anion transport activation inthese cells. Immunoprecipitation withanti-A_2B AR antibody identified a31-kDa protein in both COS-7 and human bronchial epithelial cells.Together, these findings indicate that ADO and its nucleotides arecapable of activating wtCFTR-dependent halide permeability throughA_2B AR and that this AR subtype ispresent in human bronchial epithelium. We also present data showingthat this pathway can activate clinically significant mutant CFTRmolecules such as R117H.     

Facility Delivery,Postnatal Care and Neonatal Deaths in India: Nationally-Representative Case-Control Studies

Objective

Clinical studies demonstrate the efficacy of interventions to reduce neonatal deaths, but there are fewer studies of their real-life effectiveness. In India, women often seek facility delivery after complications arise, rather than to avoid complications. Our objective was to quantify the association of facility delivery and postnatal checkups with neonatal mortality while examining the “reverse causality” in which the mothers deliver at a health facility due to adverse perinatal events.

Methods

We conducted nationally representative case-control studies of about 300,000 live births and 4,000 neonatal deaths to examine the effect of, place of delivery and postnatal checkup on neonatal mortality. We compared neonatal deaths to all live births and to a subset of live births reporting excessive bleeding or obstructed labour that were more comparable to cases in seeking care.

Findings

In the larger study of 2004–8 births, facility delivery without postnatal checkup was associated with an increased odds of neonatal death (Odds ratio = 2.5; 99% CI 2.2–2.9), especially for early versus late neonatal deaths. However, use of more comparable controls showed marked attenuation (Odds ratio = 0.5; 0.4–0.5). Facility delivery with postnatal checkup was associated with reduced odds of neonatal death. Excess risks were attenuated in the earlier study of 2001–4 births.

Conclusion

The combined effect of facility deliveries with postnatal checks ups is substantially higher than just facility delivery alone. Evaluation of the real-life effectiveness of interventions to reduce child and maternal deaths need to consider reverse causality. If these associations are causal, facility delivery with postnatal check up could avoid about 1/3 of all neonatal deaths in India (~100,000/year).