Recubrimientos para heridas con Aloe-gel combinado con alginato, pectina y quitosano: aplicaciones in vivo

La recuperación de las heridas en la piel es un proceso complejo e interrelacionado que se desarrolla a través de varias fases (hemostasia, inflamatoria, proliferativa y remodelación). El Aloe-gel (AG) ha sido considerado un biomaterial que puede coadyuvar en la modulación, regeneración y aceleración de la recuperación del tejido celular dañado e incluso se ha recomendado para su aplicación en heridas o quemaduras superficiales de tipo cutáneas.Debido a lo anterior, se ha promovido el uso del AG como un importante biomaterial que puede ser utilizado en la fabricación de recubrimientos para heridas (RH). Sin embargo, su aplicación directa sobre las heridas presenta desventajas, ya que puede inducir a deshidratación en la zona, rápida oxidación de sus fitoconstituyentes y baja proporción de solutos. Una estrategia que puede ayudar a conservar su actividad biológica y a sus componentes inalterados y funcionales, es su incorporación hacia matrices de polisacáridos como el alginato, pectina y quitosano. Aunque existen ya algunos biomateriales de esta mezcla que se han propuestos como RH, su aplicación en modelos in vivo es aún limitado. Por lo anterior, la presente revisión pretende documentar el desarrollo de RH con AG incorporado en polisacáridos y sus efectos en la recuperación de heridas in vivo.

Human intestinal protozoa in fresh asparagus from different types of markets in northwest Mexico

Caborca is one of the most productive asparagus-growing regions in the state of Sonora in northwest Mexico, an area where some fresh fruits and vegetables are sold at unregulated open-air street markets. This is a cross-sectional study in which fifty bundles of asparagus for exportation, 50 bundles of sub-standard asparagus, and 50 bundles of asparagus from open-air markets were selected randomly and then subjected to Faust, Kinyoun and ELISA testing to detect intestinal parasites. Pearson's chi-square (χ2) and Student-NewmanKeuls tests were used to estimate differences among the sampling site groups (P < 0.05). The pathogens Cryptosporidium spp. (29%) G. intestinalis (5%) and Cyclospora spp. (3%) were found in the asparagus sold in the region. The prevalence of Cryptosporidium spp. was higher in both the sub-standard asparagus and the product sampled from the open-air markets than in the samples for exportation (P < 0.05). This is the first study to demonstrate contamination by intestinal parasites in asparagus sold in different markets in northwest Mexico.

Cromatografía de interacción hidrofóbica como método de separación de proteasas alcalinas de vísceras de Scomberomorus sierra

Este estudio se enfocó en recuperar proteasas alcalinas de vísceras de Scomberomorus sierra  mediante cromatografía de interacción hidrofóbica. Tres proteasas alcalinas se lograron separar parcialmente usando esta técnica cromatográfica; dos de ellas con pesos moleculares de 19 y 31 kDa fueron identificadas como enzimas tipo tripsina de acuerdo a ensayos de inhibición. La proteasa alcalina con peso molecular de 31 kDa, única enzima aislada, fue purificada bajo las siguientes condiciones cromatográficas: sulfato de amonio l3% (p/v) y etilenglicol al 27% (p/v); esta enzima mostró actividad máxima a pH 9 – 10 y 50 – 60 °C y fue fuertemente inhibida por el inhibidor de tripsina de soya (SBTI) como por el inhibidor de tripsina porcina (TPI). Una tercera proteasa alcalina con peso molecular de 20 kDa fue parcialmente separada e inhibida por tosil fenilalanil clorometil cetona (TPCK), la cual mostró actividad óptima a pH 9 – 11 y 60 °C. Estos resultados muestran que las vísceras de Scomberomorus sierra podrían ser de utilidad como fuente de proteasas.

Prevalence and associated risk factors for Giardia and Cryptosporidium infections among children of northwest Mexico: a cross-sectional study

BACKGROUND

G. intestinalis and Cryptosporidium spp. are responsible for gastrointestinal infections worldwide. Contaminated food, feces, drinking water and predictors such as poverty, cultural and behavioral aspects have been involved in their transmission. Published studies about these infections are limited in Mexico. Cananea, Sonora is located in northwest Mexico and is one of the regions with the lowest marginalization index in the Sonora state. However, its rate of gastrointestinal infections increased from 48.7/1000 in 2003 to 77.9/1000 in 2010 in the general population. It was estimated that the prevalence of giardiasis can range from 20 to 30% in the Sonoran childhood population. However, the prevalence of giardiasis and cryptosporidiosis are unknown in Cananea, Sonora and they are likely contributing to its gastrointestinal infections rates.

METHODS

A total of 173 children (average age 8.8 ± 2.8 years) participated in this cross-sectional study. Anthropometric measurements and stool analysis were performed. Socioeconomic, cultural and symptomatology information were collected. The association between the risk factors and intestinal parasitic infections was analyzed by multivariate analysis using the STATA/SE package at a significance level of p ≤ 0.05.

RESULTS

More than half of the children (n = 103, 60%) had intestinal parasitic infections. Cryptosporidium spp. showed the highest prevalence (n = 47, 27%), which was followed by G. intestinalis (n = 40, 23%). Children with giardiasis and cryptosporidiosis had lower H/A and BMI/A Z scores than children who were free of these infections. Children with giardiasis were at higher risk (OR = 4.0; 95%CI = 1.11-13.02; p = 0.030) of reporting abdominal pain, and children who drank tap water were at higher risk (OR = 5.0; 95% CI = 1.41-17.20; p = 0.012) of cryptosporidiosis.

CONCLUSIONS

This was the first epidemiological study conducted in children in the region of Cananea, Sonora in northwest Mexico. The findings revealed a high prevalence of cryptosporidiosis and giardiasis, and their interactions with multiple risk factors were investigated. This study suggested that giardiasis and cryptosporidiosis may play an important role as causative factors of gastrointestinal diseases in the study region. Regional authorities must analyze water for human consumption to search for Cryptosporidium spp. and G. intestinalis.