The effects of chronic administration of alpha-tocopherol or melatonin, or acute ascorbic acid administration on the convulsant action of methylmalonic acid (MMA) were investigated in adult male rats. Animals were chronically injected with alpha-tocopherol (40 mg kg(-1), i.p.), melatonin (5 mg kg(-1), i.p.) or vehicle for 7 days. Buffered MMA (6 micromol/2 microl) or NaCl (9 micromol/2 microl) was injected intrastriatally and the animals were observed for the appearance of clonic or tonic-clonic convulsions and rotational behavior. Ascorbic acid (100 mg kg(-1), s.c.) was administered 30 min before MMA injection. Alpha-tocopherol and ascorbic acid pretreatment decreased the duration of the convulsive episodes and the rotational behavior elicited by MMA. This study provides evidence that free radical generation may participate in the convulsant effects of methylmalonic acid.

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Guanidino compounds play specific physiological and pathological roles in the central nervous system. We investigated the effect of an intrahippocampal infusion of GMP (a guanidino compound) administered immediately post-training on the inhibitory avoidance learning paradigm in rats. Bilateral intrahippocampal micro-injection of GMP (0-30 nmol) caused a dose-dependent increase in test step-down latencies which was completely reversed by intrahippocampal co-administration of muscimol or baclofen (GABA agonists) or preadministration (15 min pre-training, i.p.) of MK-801 (an NMDA antagonist). These results provide evidence for a participation of GABA and NMDA receptors in the GMP-induced increase in the test step-down latencies.

27 Background: Zika virus (ZIKV) was recently introduced in the American continent, 28 probably transmitted by Aedes aegypti and possibly by Ae. albopictus and Culex 29 quinquefasciatus in urban environments. ZIKV represents a known public health 30 problem as it has been involved in newborn cases of congenital microcephaly in South 31 America since 2005. The transmission of this virus in forested areas of other countries 32 and its relative ubiquity in relation to its vectors and reservoirs raises suspicions of its 33 adaptation to non-human modified environments (i.e., natural forests reserve) or on this 34 continent, similar to those seen for Yellow fever virus (YFV). The objective of this 35 work was to have an epidemiological monitoring tool mapping insects as well as 36 circulating arboviruses in wild areas with low human interference. This study was based 37 on the history of the insect flavivirus spreading cycle. Methods/Principal Findings: 38 Using a previously described sensitive PCR-based assay to assess the conserved NS5 39 region of the Flavivirus genus, both YFV partial genome and ZIKV were found in pools 40 of Aedes albopictus, a sylvatic mosquito adapted to human-modified environments, and 41 in Haemagogus leucocelaenus, a sylvatic mosquito. Conclusions: This is the first report 42 of natural infection by ZIKV in mosquitoes in a sylvatic environment on the American 43 continent. The wide distribution of these mosquitoes is probably important in the 44 transmission of ZIKV. Vertical transmission indicates a higher efficiency for the 45 maintenance and transmission of the virus in nature as well as the presence of the ZIKV 46 in permanent character in the forest areas as it occurs with the YFV thus making more 47 difficult the prevention of new cases of Zika in humans.48 49 50 3 51 Author Summary 52 Arboviruses are diseases transmitted by arthropod vectors, hence the origin of the term 53 ARthropod BOrne VIRUS, which is adopted since 1942. This work had as objective to 54 survey the circulating insects as well as to detect the presence of viruses in them. 55 Arboviruses circulate between insects and vertebrate hosts, having importance for 56 promoting diseases in humans and animals. The diseases most known at the time, due to 57 the recent cases reported by South America, are Dengue, Zika, Yellow Fever and 58 Chikungunya. For this study, we used appropriate traps to collect the insects and their 59 eggs in wild areas where there is little human interference. After collection, mosquitoes 60 and / or eggs were identified and separated as to the source and species. The eggs were 61 kept in laboratory conditions for the hatching of new insects. All the insects obtained 62 were separated into pools to be macerated and thus extract the RNA from the viruses to 63 be studied. Using molecular biology techniques, in our case the RT-PCR (Reverse 64 Transcriptase Polymerase Chain Reaction), we amplified the RNA and in sequentially, 65 we performed the sequencing reaction. With sequencing, it is possible to iden...