Background: Human Respiratory Syncytial Virus (HRSV) is a major viral pathogen associated with acute lower respiratory tract infections (ALRTI) in children. Using monoclonal antibodies against virus proteins, it is categorized into two distinct major groups, A and B. The second hypervariable region of the G protein ectodomain gene provides a reliable surrogate for phylogenetical studies. We carried out a phylogenetic analysis of the HRSV strains isolated from children hospitalized with ALRTI in Malaysia.Methods: Nasopharyngeal aspirates (NPA) were taken from children less than five years of age hospitalized with ALRTI to Hospital Serdang, Malaysia. RT-PCR was used to detect HRSV. The second hypervariable region at the carboxyl-terminal of the G gene was amplified and sequenced using primer sets GPA/F1 and GPB/F1. Neucleotide sequences were edited and aligned with Bioedite software and Clustal X program. The phylogenetic relationships of the samples were determined separately for group A and B using neighbor joining (NJ), maximum parsimony (MP) and Bayesian methods (BI).Results: HRSV was detected in 83 of 165 (50.3%) patients studied. Sequence analysis of 32 isolates showed that multiple lineages of HRSV group A and B serotypes co-circulated. The topologies resulting from the different methods (NJ, MP and BI) congruent with each other. Phylogenetic analysis of nine retrieved sequences showed that all the HRSV-A strains were clustered into the NA1 genotype. All the 23 HRSV-B strains belonged to BA genotypes consisted of a 60-nucleotide duplication region. They were classified into three different genotypes of BA10, BA9 and BA4, respectively.Conclusion: HRSV played a prominent role for hospitalization of children in our study. The sequences of the second hypervariable region of G protein ectodomain gene from HRSV A and B demonstrated remarkable genetic diversity. The present finding seems to be consistent with other studies which found the newly emerged HRSV genotypes of NA1 and BA genotypes are replacing the previously dominant genotypes. This is the first documentation of the phylogenetic relationship and genetic diversity of HRSV isolates among hospitalized children diagnosed with ALRTI in Malaysia.

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Plasma ADMA levels were significantly higher in the ERA patients. A statistically significant negative effect of ADMA levels on CFR value was observed. The effect of ADMA levels on IMT is not significant.

Background and purpose: Phosphodiesterase-5 inhibitors are beneficial in pulmonary hypertension and congestive heart failure, the two conditions associated with coronary heart disease and ischaemia. We investigated whether sildenafil counteracts the cardiovascular alterations induced by N o -nitro-L-arginine methyl ester (L-NAME) in the rat. Experimental approach: Sildenafil was given orally to rats at doses of 0.37, 0.75 or 1.5 mg kg À1 day À1 for four weeks, either alone or with L-NAME (35-40 mg kg À1 day À1 in the drinking water). Systolic blood pressure and urinary parameters (6-ketoprostaglandin F 1a , thromboxane B 2 , 8-isoprostane-prostaglandin F 2a and nitrite/nitrate) were measured in conscious rats. Isolated hearts were subjected to low flow ischaemia-reperfusion, and myocardial levels of guanosine 3', 5'cyclic monophosphate (cGMP) were determined. Endothelial vascular dysfunction was examined in aortic rings. Key results: Sildenafil dose-dependently prevented the rise in systolic blood pressure in L-NAME-treated rats. This activity was associated with a normalization of urinary 8-isoprostane-prostaglandin F 2a and other biochemical parameters. In perfused hearts, the post-ischaemic ventricular dysfunction was worse in preparations from L-NAME-treated rats than in controls. Sildenafil dose-dependently reduced this effect, and creatine kinase and lactate dehydrogenase release were lower too. cGMP levels, which were low in myocardial tissue from L-NAME-treated rats, were restored by sildenafil. In noradrenalineprecontracted aortic rings from L-NAME-treated rats acetylcholine lost its vasorelaxant effect, and sildenafil restored it. Conclusion and implications: In a rat model of chronic nitric oxide deprivation, where hypertension and aggravation of postischaemic ventricular dysfunction are associated with loss of vascular endothelium-relaxant function, sildenafil provided significant cardiovascular protection, primarily by maintaining tissue cGMP levels.

Rheumatoid arthritis (RA) is associated with enhanced atherosclerosis and impaired endothelial function early after the onset of the disease and cardiovascular (CV) disease represents one of the leading causes of morbidity and mortality. It is well known that disease modifying antirheumatic drugs (DMARDs) are able to improve the course of the disease and the quality of life of these patients, but little is known about the effects of DMARDs on CV risk and endothelial dysfunction. Our goal was to examine the effects of long‐term therapy with DMARDs on endothelial function and disease activity in early RA (ERA). Twenty‐five ERA patients (mean age 52 ± 14.6 years, disease duration 6.24 ± 4.10 months) without evidence of CV involvement were evaluated for disease activity score (DAS‐28), 2D‐echo derived coronary flow reserve (CFR), common carotid intima‐media thickness (IMT) and plasma asymmetric dimethylarginine (ADMA) levels at baseline and after 18 months of treatment with DMARDs (10 patients with methotrexate and 10 with adalimumab). DMARDs significantly reduced DAS‐28 (6.0 ± 0.8 vs. 2.0 ± 0.7; P < 0.0001) and improved CFR (2.4 ± 0.2 vs. 2.7 ± 0.5; P < 0.01). Common carotid IMT and plasma ADMA levels did not show significant changes. The present study shows that DMARDs, beyond the well known antiphlogistic effects, are able to improve coronary microcirculation without a direct effect on IMT and ADMA, clinical markers of atherosclerosis. Treatment strategies in ERA patients with high inflammatory activity must be monitored to identify beneficial effects on preclinical markers of vascular function.