Identification of serologically active Helicobacter pylori antigens related to alterations in serum pepsinogen levels / Identificación de antígenos de Helicobacter pylori serológicamente activos relacionados con alteraciones en los niveles de pepsinógenos en suero

Resumen El adenocarcinoma gástrico se asocia con la infección por Helicobacter pylori. La transición a un proceso de carcinogénesis está precedida por atrofia glandular, y los niveles séricos de pepsinógeno I y II (PGI y PGII) se correlacionan con este tipo de lesiones gástricas. El objetivo del trabajo fue estudiar posibles asociaciones de los niveles de pepsinógenos (PG) en suero en relación con la frecuencia de actividad serológica hacia antígenos de H. pylori. Se utilizaron muestras de suero de pacientes con patología gástrica asociada a H. pylori (n = 26) y de individuos asintomáticos como controles (n = 37). Los antígenos seroactivos se identificaron mediante inmunoblot utilizando un extracto proteico de H. pylori. Los títulos de anticuerpos anti-H. pylori y la concentración de PG en suero se determinaron por ELISA. De los 31 antígenos seroactivos identificados, 9 presentaron una frecuencia diferencial entre ambos grupos (116,7; 68,8; 61,9; 54,9; 45,6; 38,3; 36,5; 33,8 y 30,1 kDa) y solo 3 se relacionaron con niveles alterados de PG en suero. En el grupo control, la seropositividad del antígeno de 33,8 kDa se relacionó con un aumento de PGII, mientras que el antígeno de 68,8kDa se relacionó con valores normales de PG (PGII disminuido y PGI/PGII elevado), sugiriendo que la seropositividad a este antígeno podría ser un factor protector frente a patologías gástricas. La seropositividad del antígeno de 54,9 kDa se relacionó con valores alterados de PG indicadores de inflamación y atrofia gástrica (aumento de PGII y disminución de PGI/PGII). La identificación de alteraciones séricas en los niveles de pepsinógeno relacionadas con la seropositividad a los antígenos de 33,8; 54,9 y 68,8 kDa de H. pylori sienta un precedente para futuros estudios como posibles biomarcadores serológicos pronósticos.

Identification of serologically active Helicobacter pylori antigens related to alterations in serum pepsinogen levels.

Gastric adenocarcinoma is associated with Helicobacter pylori infection. The transition to a carcinogenic process is preceded by glandular atrophy and serum levels of pepsinogen I and II (PGI and PGII) correlate with this type of gastric lesions. Possible associations of serum PG levels in relation to the frequency of serological activity against H. pylori antigens were studied. Serum samples from patients with gastric pathology associated with H. pylori (n=26) and asymptomatic individuals as controls (n=37) were used. Seroactive antigens were identified by immunoblot using a protein extract of H. pylori. The antibody titers anti-H. pylori and the concentration of PGs in serum was determined by ELISA. Thirty-one seroactive antigens were identified, nine of which exhibited a differential frequency between both groups (116.7, 68.8, 61.9, 54.9, 45.6, 38.3, 36.5, 33.8 and 30.1kDa) and only 3 were related to altered levels of PGs in serum. In the control group, the seropositivity of the 33.8kDa antigen was related to an increase in PGII, while the 68.8kDa antigen was related to normal PG values (decreased PGII and elevated PGI/PGII levels) indicating that seropositivity to this antigen could be a protective factor to gastric pathology. The seropositivity of the 54.9kDa antigen was related to altered values of PGs indicative of inflammation and gastric atrophy (increased in PGII and decreased in PGI/PGII). The identification of serum alterations in pepsinogen levels related to seropositivity to H. pylori 33.8, 54.9 and 68.8kDa antigens sets a precedent for further study as possible prognostic serological biomarkers.

Characterisation by Excitation-Emission Matrix Fluorescence Spectroscopy of Pigments in Mucus Secreted of Earthworm Eisenia foetida Exposed to Lead.

The earthworm exposed to toxics shows physiological responses as: avoidance and mucus secretion. Heavy metals are particularly toxic to earthworms and the mucus secretion has been considered as a defence mechanism against undesirable substance. The chromophores present in the mucus secretion of Eisenia foetida have been poorly studied. Mucus secretion of E. foetida was induced by PbCl2. High PbCl2 concentrations provoked abundant mucus secretion which showed fluorescence when illuminated by UV light. Dialysis membrane separation, UV Visible and Excitation-Emission Matrix Fluorescence (EEM) spectroscopy were used to characterise the fluorescent pigments. EEM spectroscopy analysis of the mucus secretion signalled three excitation-emission peaks at: 310/380 nm, 370/520 nm and 440/520 nm. Two fluorophores were separated by dialysis. One of them matched the fluorescent compound riboflavin excitation-emission profile; the other is a protein with a peak 290/350 nm. Native-PAGE electrophoresis was conducted to assess the riboflavin-biding ability of the coelomic fluid protein produced by Eisenia foetida showing a high riboflavin-biding ability.

Amoebicidal Activity of Essential Oil of Dysphania ambrosioides (L.) Mosyakin & Clemants in an Amoebic Liver Abscess Hamster Model.

Amebiasis is a parasitic disease that extends worldwide and is a public health problem in developing countries. Metronidazole is the drug recommended in the treatment of amebiasis, but its contralateral effects and lack of continuity of treatment induce low efficiency, coupled with the appearance of resistant amoebic strains. Therefore, the search of new compounds with amoebicidal activity is urgent and important. In this study, we evaluated the in vitro and in vivo antiamoebic activity of the essential oil Dysphania ambrosioides (L.) Mosyakin & Clemants. It exhibited an IC50 = 0.7 mg/mL against trophozoites. The oral administration of essential oil (8 mg/kg and 80 mg/kg) to hamster infected with Entamoeba histolytica reverted the infection. Ascaridole was identified as the main component of essential oil of D. ambrosioides. The identification of amoebicidal activity of Ascaridole gives support to the traditional use. Further studies with Ascaridole will be carried out to understand the mechanism involved.