Maria M González | PubMed Health

PubMed2006

[Detecting poliovirus in wastewater from Armenia, Colombia].

OBJECTIVES: Implementing environmental surveillance for poliovirus circulating from wastewater. METHODS: Six wastewater samples were collected from each final site within a wastewater collection system in Armenia, Quindío. Virus was extracted and concentrated by a method using polyethylenglycol and sodium chloride as concentrating agent. Polioviruses were identified by polymerase chain reaction assay with group-specific, serotype-specific and Sabin vaccine-specific primers. RESULTS: It was confirmed that the viral detection method is highly efficient. Poliovirus was detected in 5 of 6 (83%) samples collected. Serotype-specific identification revealed the presence of type 1 and type 3 polioviruses in the samples. All of them were of the vaccine type, which provided evidence regarding the non-circulation of wild poliovirus in the country. CONCLUSION: Wastewater surveillance can be a sensitive tool for detecting poliovirus circulation.

Colombia↗

PubMed2005

Endothelial hypoxic preconditioning in rat hypoxic isolated aortic segments.

Our aim was to analyse endothelial hypoxic preconditioning after hypoxia-reperfusion (HR). Endothelial functionality was analysed through the vasorelaxation responses to acetylcholine (Ach) and the level of serine1177 phosphorylated endothelial nitric oxide synthase (eNOS) (ser1177-eNOS) measured by Western blot in in vitro hypoxic preconditioned (P + HR) isolated rat aortic segments. Relaxation in response to Ach was reduced in phenylephrine-precontracted aortic segments after HR (control: IC50, 5 +/- 2.5 x 10(-8) mol l(-1); HR: IC50, 3 +/- 1.2 x 10(-7) mol l(-1); P < 0.05). Ach-dependent vasodilatation was improved by P + HR. The content of ser1177-eNOS in the HR segments was 1.5-fold lower than in P + HR. Confocal microscopy showed an increased content of both superoxide anion and peroxynitrite in the vascular wall of HR aortic segments, which it was reduced by P + HR. Geldanamycin (10 microg ml(-1)), an agent known to inhibit heat shock protein 90 (hsp90), reduced the level of ser1177-eNOS in P + HR aortic segments. However in the presence of geldanamycin, endothelial hypoxic preconditioning persisted. We conclude that short periods of hypoxia induced endothelial hypoxic preconditioning that was accompanied by enhanced levels of ser1177-eNOS in the vascular wall. The fact that endothelial hypoxic preconditioning persisted in the presence of geldanamycin suggests that other molecular mechanisms are involved in the endothelial adaptation to HR injury.

Acetylcholine↗