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Status epilepticus (SE) is one of the recognized primary precipitating events that can lead to temporal lobe epilepsy (TLE) associated with hippocampal sclerosis. This type of epilepsy is characterized by poor response to drug treatment, often requiring surgical intervention to remove the mesial temporal regions involved in the seizure onset. However, even neurosurgery may not be completely successful. Thus, the prevention of hippocampal damage and epileptogenesis is currently evaluated as a possible alternative therapeutic approach to prevent the development of pharmacoresistant TLE. Lines of evidence suggest that ischemic-hypoxic lesions might occur in different brain regions, including the hippocampus, during SE. Especially in the hippocampal CA3 region, an ischemic-like lesion develops in the stratum lacunosum-moleculare and is mainly characterized by a loss of astrocytes and neuronal processes and increased immunostaining of pimonidazole which probes areas exposed to hypoxia. Interestingly, these mechanisms can contribute to neuronal cell loss and may be counteracted by drugs that can afford vascular protection, as in the case of ligands of the ghrelin receptor. Notably, some of the ghrelin receptor ligands possess a double edge effect, since they are anticonvulsant and vascular-protective, thus, potentially representing new tools to counteract the consequences of SE. This article is part of a Special Issue entitled "Status Epilepticus"., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Alterations in the intracellular levels of calcium are a common response to cell death stimuli in animals and fungi and, particularly, in the Neurospora crassa response to staurosporine. We highlight the importance of the extracellular availability of Ca 2+ for this response. Limitation of the ion in the culture medium further sensitizes cells to the drug and results in increased accumulation of reactive oxygen species (ROS). Conversely, an approximately 30-fold excess of external Ca 2+ leads to increased drug tolerance and lower ROS generation. In line with this, distinct staurosporine-induced cytosolic Ca 2+ signaling profiles were observed in the absence or presence of excessive external Ca 2+ . High-throughput RNA sequencing revealed that different concentrations of extracellular Ca 2+ define distinct transcriptional programs. Our transcriptional profiling also pointed to two putative novel Ca 2+ -binding proteins, encoded by the NCU08524 and NCU06607 genes, and provides a reference dataset for future investigations on the role of Ca 2+ in fungal biology., Competing Interests: Conflict of interest: The authors declare no conflict of interest.

In models of status epilepticus ghrelin displays neuroprotective effects mediated by the growth hormone secretagogue-receptor 1a (GHS-R1a). This activity may be explained by anticonvulsant properties that, however, are controversial. We further investigated neuroprotection and the effects on seizures by comparing ghrelin with a more effective GHS-R1a agonist, JMV-1843. Rats were treated either with ghrelin, JMV-1843 or saline 10 min before pilocarpine, which was used to induce status epilepticus. Status epilepticus, developed in all rats, was attenuated by diazepam. No differences were observed among the various groups in the characteristics of pilocarpine-induced seizures. In saline group the area of lesion, characterized by lack of glial fibrillary acidic protein immunoreactivity, was of 0.45 ± 0.07 mm(2) in the hippocampal stratum lacunosum-moleculare, and was accompanied by upregulation of laminin immunostaining, and by increased endothelin-1 expression. Both ghrelin (P<0.05) and JMV-1843 (P<0.01) were able to reduce the area of loss in glial fibrillary acidic protein immunostaining. In addition, JMV-1843 counteracted (P<0.05) the changes in laminin and endothelin-1 expression, both increased in ghrelin-treated rats. JMV-1843 was able to ameliorate neuronal survival in the hilus of dentate gyrus and medial entorhinal cortex layer III (P<0.05 vs saline and ghrelin groups). These results demonstrate diverse protective effects of growth hormone secretagogues in rats exposed to status epilepticus.

Neurosteroids (NSs) are well known modulators of neuronal activity and by binding to different neuronal receptors are responsible for a broad spectrum of biological and pathophysiological conditions. Here, a sensitive liquid chromatographic-electrospray ionization-tandem mass spectrometric method (LC-ESI-MS/MS) has been developed and validated for the simultaneous determination in rat brain areas of three NSs, i.e. pregnenolone sulphate (PS), dehydroepiandrosterone (DHEA) and allopregnanolone (AP). NSs were extracted with methanol-formic acid, purified by Hybrid-SPE cartridges and subjected to LC-ESI-MS/MS without any preliminary derivatization or deconjugation procedure. Quantitation was performed by multiple reaction monitoring mode with the internal standard method, using deuterium-labelled analogues of the analyzed NSs. The proposed method provided for the first time a direct quantitative determination of PS without hydrolysis; in particular, PS concentrations were found significantly (p<0.01) higher in hippocampus, the brain area associated primarily with memory, than in cortical tissue of control rats, suggesting the important role of this NS in the process of memory formation. The developed method could be successfully applied to quantify simultaneously PS, DHEA and AP levels in brain tissue in order to study their changes during various neurodegenerative diseases and to investigate the role of PS in the brain., (Copyright © 2013 Elsevier B.V. All rights reserved.)

We have studied the changes in the fatty acid profiles of red blood cell membrane phospholipids in 47 infants who were exclusively fed human milk from birth to 1 month of life. Twenty blood samples were obtained from cord, 15 at 7 days and 12 at 30 days after birth. Membrane phospholipids were obtained from erythrocyte ghosts by thin-layer chromatography and fatty acid composition was determined by gas liquid chromatography. Phosphatidylcholine showed the most important changes during early life; stearic, w6 eicosatrienoic and arachidonic acids decreased whereas oleic and linoleic acids increased. In phosphatidylethanolamine, palmitic and stearic acid declined and oleic, linoleic and docosahexenoic acids increased with advancing age. Small changes were noted for individual fatty acids in phosphatidylserine. In sphingomyelin stearic acid increased from birth to 1 month and linoleic, arachidonic and nervonic acids decreased. Total polyunsaturated fatty acids of the w6 series greater than 18 carbon atoms increased with advancing age in phosphatidylethanolamine and decreased in choline and serine phosphoglycerides and in sphingomyelin. Long chain fatty acids derived from linoleic acid decreased in phosphatidylcholine but increased in ethanolamine and serine phosphoglycerides. The different behavior in the changes observed in fatty acid patterns for each erythrocyte membrane phospholipid may be a consequence of its different location in the cell membrane bilayer and specific exchange with plasma lipid fractions.

The fatty acid and cholesterol contents of tissue membranes are the determinants of membrane stability and functionality. This study was designed to evaluate the influence of a high monounsaturated fatty acid diet on the fatty acid composition of rat liver microsomes and on their cholesterol and lipid phosphorus content. Weanling animals were fed for 5 weeks with high fat diets containing olive oil or corn oil. Saturated fatty acids were increased and oleic acid decreased in microsomal total phospholipids and in the three major phosphoglycerides, phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI), of rats fed corn oil as compared to the olive oil group. The percentage of linoleic acid was higher in the corn oil group, but only for total phospholipids and PC. Linoleic and alpha-linolenic metabolites were significantly increased in total phospholipids of olive oil-fed animals with respect to those fed corn oil. These changes were responsible for the low unsaturation index found in microsomal phospholipids of the corn oil group. The diet did not affect the microsome cholesterol or the lipid phosphorus content. These results show that, in olive oil-fed rats, the cholesterol content and the degree of unsaturation of liver microsomes was similar to that observed in weanling animals; this probably suggests an adequate maintenance of functionality of membranes in olive oil-fed animals.

This study was designed to determine the polyunsaturated fatty acid (PUFA) composition of plasma lipid fractions in newborn infants fed human milk (HM), milk formula (MF) or nucleotide-supplemented milk formula (NMF) during the first month of life. Linoleic acid was increased in infants fed formulas in all plasma lipid fractions with respect to those fed HM. Plasma phospholipids in MF-fed infants had lower percentages of PUFA of both omega 6 and omega 3 series, namely arachidonic and docosahexaenoic acids, than those fed HM or NMF; the unsaturation index was decreased in infants fed MF as compared to those fed HM or NMF. Arachidonic acid showed a similar behaviour in plasma cholesteryl esters as in phospholipids. No changes for long chain PUFA among the groups studied were observed for plasma triglycerides and free fatty acids. These results support previous findings that dietary nucleotides are involved in the regulation of desaturation and elongation of linoleic and linolenic acid to their longer superior homologous fatty acids. We suggest that dietary nucleotides may reverse the partial inhibition of delta 5-desaturase caused by an excess of linoleic acid in the diet during early postnatal life.

Additional evidence is given that in Streptomyces strains R39, R61, and K11 the same enzyme performs dd-carboxypeptidase and transpeptidase activities and that this enzyme is the killing site of beta-lactam antibiotics. With strain R61, it was found that the exocellular enzyme has a sensitivity towards some antibiotics different from that of the membrane-bound enzyme. Under the growth conditions used in the present investigations, beta-lactamase activity was not involved in susceptibility to beta-lactam antibiotics.