Brazilian psychiatric brain bank: a new contribution tool to network studies.

There is an urgent need for expanding the number of brain banks serving psychiatric research. We describe here the Psychiatric Disorders arm of the Brain Bank of the Brazilian Aging Brain Study Group (Psy-BBBABSG), which is focused in bipolar disorder (BD) and obsessive compulsive disorder (OCD). Our protocol was designed to minimize limitations faced by previous initiatives, and to enable design-based neurostereological analyses. The Psy-BBBABSG first milestone is the collection of 10 brains each of BD and OCD patients, and matched controls. The brains are sourced from a population-based autopsy service. The clinical and psychiatric assessments were done by an expert team including psychiatrists, through an informant. One hemisphere was perfused-fixed to render an optimal fixation for conducting neurostereological studies. The other hemisphere was comprehensively dissected and frozen for molecular studies. In 20 months, we collected 36 brains. A final report was completed for 14 cases: 3 BDs, 4 major depressive disorders, 1 substance use disorder, 1 mood disorder NOS, 3 obsessive compulsive spectrum symptoms, 1 OCD and 1 schizophrenia. The majority were male (64%), and the average age at death was 67.2 ± 9.0 years. The average postmortem interval was 16 h. Three matched controls were collected. The pilot stage confirmed that the protocols are well fitted to reach our goals. Our unique autopsy source makes possible to collect a fairly number of high quality cases in a short time. Such a collection offers an additional to the international research community to advance the understanding on neuropsychiatric diseases.

Ontogenetic development of Loxosceles intermedia spider venom.

Envenomation by Loxosceles spider has become a public health problem in the South region of Brazil, mainly due to high levels of domiciliary infestation by Loxosceles intermedia spiders. The toxic effects of L. intermedia venom are mostly associated with a 35 kDa protein (F35) which presents complement-dependent haemolytic and dermonecrotic activities. The aim of this study was to detect, through biological and immunochemical assays, the appearance of the main toxic component, F35, during the ontogenetic development of L. intermedia spiders. The toxin appeared in its fully active form in venom of third instar spiderlings; from then on its activity increased throughout development until adulthood. On the other hand, F35 was not detected in extracts of either eggs or spiderlings of the first and second instars.