Beneficial effects of the n-3 long-chain polyunsaturated fatty acids in surgical patients: updating the evidence

The use of n-3 polyunsaturated fatty acids in surgical patients has risen by the fact that this may attenuate systemic and acute inflammatory responses secondary to surgical trauma through modulation of inflammatory mediators and cell membrane interactions. Moreover, the inclusion of n-3 fatty acids in clinical trials as part of the therapy in patients, who expect to undergo a surgical stress, suggests benefits on clinical progress. Therefore, the objective of this article is to review data from n-3 polyunsaturated fatty acid effects on biochemical parameters and on reduced length of hospitalization, number of infections, and mortality as main clinical outcomes in human surgical patients.

For ischemic brain damage, is preclinical evidence of neuroprotection by presynaptic blockade of glutamate release enough?

Some drugs blocking glutamate release produce reduced brain injury in some animal models of cerebral ischemia whereas others lack a clear effect. Meta-analysis is a widely used technique in clinical and epidemiological studies. However, it has never been used in the analysis of preclinical studies. In order to estimate quantitatively the current state of the knowledge concerning the neuroprotective effect of drugs inhibiting glutamate release and to attempt to resolve the apparent controversy in relation to the neuroprotective properties of these drugs, a meta-analysis was performed. It identified a significant difference between drugs blocking glutamate release and controls. Therefore, we hypothesize that inhibition of presynaptic glutamate release could be a major goal in neuroprotection when ischemic brain damage is present and that meta-analysia could be a useful tool for preclinical studies,

Dendritic spine pathology in infants with severe protein-calorie malnutrition

BACKGROUND

Experimental undernutrition in animals, during the critical brain development period, produces retardation of brain growth as well as a number of different morphologic and functional abnormalities in neurons, mainly in the dendritic synaptic apparatus. These alterations are the cause of the poor neurointegrative development that occurs in experimental malnutrition. Severe malnutrition during early postnatal life in humans is known to produce similar neurointegrative disorders as well as mental retardation, but there are very few studies describing the morphology of the dendritic apparatus in infants suffering from this condition.

OBJECTIVE

To study the dendritic spine density and morphology in dendrites from cortical neurons in infants dying from severe malnutrition.

METHODOLOGY

Brain sections from the somestesic, motor, and occipital cortical areas of 13 infants who died of severe malnutrition and 7 eutrophic infants who died of other causes were studied by means of the rapid Golgi method. Apical dendritic spines from neurons of the fifth cortical layer were studied and counted in all sections.

RESULTS

Apical dendrites were significantly shorter in malnourished infants than in the control group (581.54 +/- 54.32 microm in severe malnutrition vs 846.3 microm in normal infants). The number of dendritic spines per dendrite was also significantly diminished (185.3 +/- 36.1 in malnourished vs 374.3 +/- 41.6 in eutrophic infants). There were marked morphologic abnormalities in the dendritic spines of infants dying of severe malnutrition that were classified as dysplastic.

CONCLUSIONS

Short apical dendrites, fewer spines, and dendritic spine abnormalities occur in severe infant malnutrition. These anatomic anomalies might be related to the neuropsychological deficits that occur in these children.