Impact of polyploidy on plant tolerance to abiotic and biotic stresses.

Polyploidy, defined as the coexistence of three or more complete sets of chromosomes in an organism's cells, is considered as a pivotal moving force in the evolutionary history of vascular plants and has played a major role in the domestication of several crops. In the last decades, improved cultivars of economically important species have been developed artificially by inducing autopolyploidy with chemical agents. Studies on diverse species have shown that the anatomical and physiological changes generated by either natural or artificial polyploidization can increase tolerance to abiotic and biotic stresses as well as disease resistance, which may positively impact on plant growth and net production.

Effect of probiotic supplementation on immunoglobulins, isoagglutinins and antibody response in children of low socio-economic status.

Background: Antigen exposure is one of the major exogenous factors modulating human immunocompetence acquisition. Decline in family size and improvements in public health and hygiene in developed countries, may deprive the immune system of appropriate antigen input by diminishing infectious stimuli. Probiotics are a large group of microorganisms defined by their beneficial effects on human health and with stimulating effects on different functions of the immune system.

[Blood lead levels in children from the city of La Plata, Argentina. Relationship with iron deficiency and lead exposure risk factors].

Introduction: Environmental exposure to lead and the subsequent poisoning are a main public health concern worldwide. Children have a higher vulnerability to lead toxic effects, and many reports have shown the association between iron deficiency and lead poisoning. In Argentina, reports about lead levels in children are scarce.

[Age-related loss of maternal antibodies against measles in children in La Plata].

Measles outbreaks every 3-4 years have occurred in Argentina. The vaccine was introduced in 1978 as part of a regular program, and the age for the first vaccination was changed to one year old. The optimal age for first measles vaccination is defined as that age with the highest proportion of infants responding to the vaccine.