Effect of parasitism of Lernaea cyprinacea on tadpoles of the invasive species Lithobates catesbeianus.

The introduction of invasive species is one of the greatest threats currently faced by natural ecosystems, causing ecological imbalances between native populations and transmission of a variety of diseases. We reported the interaction between two exotic species given by the parasitic infestation of the copepod Lernaea cyprinacea in the early stages of the development of the American bullfrog Lithobates catesbeianus in the central area of Argentina. In this paper we analysed the leukocyte profile of parasitized and non-parasitized tadpoles of L. catesbeianus with L. cyprinacea and their body condition (BC) as biomarkers of the health status of organisms. A total of 27 tadpoles of L. catesbeianus were analysed (12 non-parasitized and 15 parasitized). The lower BC recorded in parasitized organisms show a lower health status in these tadpoles, which could be affecting the metamorphosis and therefore impact at the population level. Leukocyte response of L. catesbeianus tadpoles to the parasitism of L. cyprinacea was found. Mature and immature lymphocyte frequencies and hematocrit were higher in parasitized compared to non-parasitized tadpoles, which is a typical response to the presence of parasites. However, eosinophils and monocytes were recorded at high frequencies in not parasitized tadpoles, which could be due to the important role played by these leucocytes in the metamorphosis of frogs. The results of this study constitute a first antecedent on leukocyte profile in aquatic stages of anurans during an ectoparasitosis and its possible implications for environmental health. The parasitism of L. cyprinacea influences the biology of the American bullfrog at both the individual and population levels. Parasitized individuals are not killed directly by the parasite, but they can create conditions for secondary infections, growth retardation, behavioral changes and, ultimately, reduce populations.

Intraoperative neurophysiological monitoring for the resection of brain tumors in pediatric patients.

Intraoperative neurophysiology (ION) is the gold standard to map and monitor brain functions during supratentorial surgery in critical areas. This is of great value for the surgery of brain gliomas in adults, but the same ION techniques can be used in the pediatric population with respect to both epilepsy and brain tumor surgery. While the principles of most ION techniques are the same for adults and children, the developing nervous system has peculiar characteristics in terms of anatomical and physiological maturation of afferent and efferent pathways within the brain and the spinal cord. Accordingly, some adjustments, particularly with regards to stimulation parameters, are needed in younger children. This paper will review current ION techniques to assist during the resection of brain tumors in children, focusing on the aspects peculiar to mapping and monitoring of sensori-motor functions in the pediatric population. On the other hand, awake surgery, of common use in adult patients when aiming to identify cortical and subcortical cognitive functions, is of very limited use in children and will not be discussed here.

Nonalcoholic fatty liver disease and the metabolic syndrome.

In the last 15 years evidence has been accumulating suggesting that hepatic steatosis may be the starting point for a progressive liver disease. Nonalcoholic steatosis (nonalcoholic fatty liver disease, NAFLD) is now considered a metabolic pathway to advanced liver disease, cirrhosis and hepatocellular carcinoma. Liver disease of other etiology, namely hepatitis C virus, may interact with NAFLD, although the underlying mechanism(s) have not been fully elucidated. Type 2 diabetes mellitus, obesity and dyslipidemia are the principal factors associated with NAFLD, which is now considered the hepatic expression of metabolic syndrome (MS). Several studies have dealt with the relationship of NAFLD and MS, the risk of liver disease associated with the classical features of MS, the importance of insulin resistance as the common soil of different diseases. We still need to clarify the mechanism(s) responsible for liver disease progression from pure fatty liver, to steatohepatitis and to cirrhosis, and the reason(s) why only a few NAFLD cases progress to terminal liver failure while others (the majority) will have a cardiovascular outcome. The epidemics of obesity and diabetes of Western countries is expected to produce a significant increase of metabolic liver disease in the next years. Prevention and intervention programs based on lifestyle are therefore mandatory to reduce the burden of metabolic liver disease.