Suicide attempts among children and adolescents: partial or total injury? / Tentativa de suicídio infanto-juvenil: lesão da parte ou do todo?

This study sought to verify the records on file and the number of cases of attempted suicide among children and adolescents who were attended by Emergency Care health professionals in the municipality of Matozinhos, Minas Gerais, Brazil. Documentary and descriptive research was conducted, the data for which was collected by means of an investigation of Outpatient Records from 2008 to 2010. Of the 73,000 files evaluated, those dealing with cases of attempted suicide among children and adolescents between the age of 3 and 18 years were selected. It was revealed that the health professionals, particularly physicians and nurses, fail to register the cases appropriately, invalidating information about the problem and potential prevention measures. The conclusion reached was that underreporting and the discrepancy of the diagnoses which were not duly referred to the competent agencies require rethinking and reviewing medical practices, and taking a systematic and careful look to address the individual as a complex whole.

Neste estudo procurou-se verificar o registro e o número de casos de tentativa de suicídio entre crianças e adolescentes do município de Matozinhos, Minas Gerais, Brasil, que foram atendidos pelos profissionais de saúde do Pronto-Atendimento. Trata-se de uma pesquisa documental e descritiva, cuja coleta dos dados ocorreu por meio de investigação nas Fichas Ambulatoriais, no período de 2008 a 2010. Das 73.000 fichas levantadas, selecionaram-se aquelas que tratavam de casos de tentativa de suicídio entre crianças e adolescentes do município, com idades entre três e 18 anos. Percebeu-se que os profissionais de saúde, mais especificamente os médicos e enfermeiros, não registram os casos de forma adequada, inviabilizando a informação sobre o problema e as medidas de prevenção. Concluiu-se que a subnotificação, a discrepância dos diagnósticos e o não encaminhamento aos órgãos competentes exigem repensar e rever a prática médica e dirigir um olhar sistematizado e cuidadoso para perceber o sujeito como um todo complexo.

Purification and characterization of an invertase produced by Aspergillus ochraceus TS.

Purification and characterization of an extracellular invertase produced by Aspergillus ochraceus TS are reported. The enzyme was purified (42-fold) from culture filtrate by salt precipitation, ion-exchange and gel filtration. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) of the purified enzyme showed a single band of molecular mass 66 kDa. The molecular mass of the native enzyme was found to be 130 kDa by gel filtration. The purity of the protein was also checked against its antiserum raised in rabbits by two-dimensional immunodiffusion in agarose gel and Western blot that showed a single band. It is a glycoprotein with mannose as its carbohydrate residue. The enzyme showed high affinity for sucrose with a Km of 3.5 mM. The amino acid analysis revealed a high proportion of acidic residues but it had a low content of cysteine, histidine and arginine comparable to other fungal invertases.

Addition of C-terminal histidyl tags to PsaL and PsaK1 proteins of cyanobacterial photosystem I.

In vitro mutagenesis was used to produce two photosystem I mutants of the cyanobacterium Synechocystis sp. PCC 6803. The mutant HK and HL contained hexahistidyl tags at the C-termini of the PsaK1 and PsaL subunits, respectively. The HK mutant contained wild-type amounts of trimeric PS I complexes, but the level of hexahistidine-tagged PsaK1 was found only ten per cent in the PS I complexes and membranes of the wild type level. Therefore, attachment of a tag at the C-terminus interferes with the expression or assembly of PsaK1. In contrast, the HL mutant contained a similar level of tagged PsaL as that in the wild type. However, trimeric PS I complexes could not be obtained from this strain, indicating that the C-terminus of PsaL is involved in the formation of PS I trimers. Hexahistidine-tagged complexes of the HL and HK strains could not be purified with Nickel-affinity chromatography, unless photosystem I was denatured with urea, demonstrating that tagged C-termini of PsaK1 and PsaL were embedded inside of the PS I complex. Protection of the C-terminus from trypsin cleavage further supported this conclusion. Thus, histidine tagging allowed us to demonstrate role of C-termini of two proteins of photosystem I.

Electrostatic interactions of charged ionizable groups with the single histidine residue in lysozyme

Foram calculadas as interaçöes eletrostáticas de grupos ionizáveis carregados positiva e negativamente com o resíduo único de histidina, em lisozima de clara de ovo, por meio de um modelo dielétrico uniforme. Na medida em que os átomos envolvidos säo expostos a um solvente ou se localizam próximo à superfície da proteína, foram consideradas somente as interaçöes mediadas pelo solvente (E=80). Foi calculada também a energia total de interaçäo G=1,84 Kcal.mol-1, equivalendo a pK=-1,34. Admitindo-se um pK=7,0 näo pertubado (intrínseco) para o resíduo de histidina, obtém-se um pK aparente de 5,7, valor de acordo com o de 5,8 encontrado na literatura. Esse procedimento simplificado é aplicável a outras proteínas que possuem grupos ionizáveis carregados expostos a solventes, com o intuito de calcular as interaçöes eletrostáticas e determinar sua influência na ionizaçäo de resíduos de aminoácidos nessas proteínas