Análise funcional in silico das variantes no gene da APOB em pacientes com hipercolesterolemia familial / In silico functional analysis of variants in the APOB gene in patients with familial hypercholesterolemia

INTRODUÇÃO: O diagnóstico molecular da hipercolesterolemia familial (HF) é atribuído principalmente as variantes nos genes LDLR, LDLRAP1, APOB e PCSK9. O objetivo deste estudo foi realizar análise in silico para investigar o impacto de variantes sem descrição na literatura no gene APOB observado em pacientes com HF. MÉTODOS: Foram selecionados 141 indivíduos com diagnóstico clínico de HF. As variantes no gene da APOB foram selecionadas após sequenciamento dos éxons de 61 genes utilizando a plataforma MiSeq (Illumina). Os dados foram analisados nos programas Real Time Analysis, MiSeq Reporter, BaseSpace Sequence Hub e VariantStudio. Para a análise in silico, as sequências molde das moléculas da apoB-100 e o LDLr foram selecionadas por modelagem comparativa considerando o maior grau de identidade. As sequências proteicas foram alinhadas e os modelos 3D foram construídos utilizando os programas SEAVIEW e MODELLER v9.21. O gráfico de Ramachandran do modelo de menor energia apresenta 0,5% de outliers e análise de regiões de desordem, como principal validação. Os resultados das conformações de ancoragem foram analisados no software PyMol 2.1. Os estudos de docking molecular foram realizados para identificar o melhor complexo de conformação usando o servidor web clusPRO. RESULTADOS: Após a análise molecular dos 141 pacientes foram identificadas 7 variantes missenses sem descrição na literatura no gene APOB (c.433C>T, c.2630C>T, c.2950G>A, c.5743G>A, c.7367C>A, c.9880T>C e c.10780T>C). Os estudos de docking das variantes demonstraram uma maior afinidade entre o LDLr e a apoB-100 (c.2630C> T; Pro877Leu) em comparação com a proteína não mutada. A troca dos resíduos permaneceu como propriedade físico-química, e comparando as distâncias de ligação das proteínas não-mutadas (5Å) e mutadas (3,5Å), sugere-se uma maior afinidade do complexo (LDLr-apoB-100) para a leucina, tal fato é afirmado pela análise da região de desordens da apoB-100, onde a posição 877 está em uma região desorganizada e flexível. Esta maior afinidade poderia levar a uma menor dissociação intracelular deste complexo, resultando em uma alta taxa de degradação do LDLr pelas enzimas lisossômicas, levando ao aumento da concentração plasmática de LDLc. Para as outras variantes não houve alterações significativas. CONCLUSÃO: Os resultados sugerem que estudos in silico baseados na ferramenta de docking molecular podem melhorar o conhecimento da contribuição genética no desenvolvimento da doença HF. Além disso, a variante APOB c.2630C> T deve ser avaliada in vitropara validação do mecanismo proposto. (AU)

Metas lipídicas: mundo real / Lipid goals: real world

INTRODUÇÃO: Frente à crescente evidência da redução de eventos cardiovasculares relacionados à redução do LDL colesterol (LDL-c), a Sociedade Brasileira de Cardiologia (SBC) propôs em 2017 metas mais agressivas de LDL-c. OBJETIVO: Avaliar em um centro terciário de cardiologia a proporção de pacientes que atingiram metas de LDL-c propostas pela Atualização da Diretriz Brasileira de Dislipidemias e Prevenção da Aterosclerose da SBC conforme estratificação de risco cardiovascular. METODOLOGIA: Foram analisados 2180 pacientes consecutivos em controle ambulatorial quanto à fatores de risco cardiovascular e terapia medicamentosa vigente. Conforme a diretriz, foram classificados em risco baixo, intermediário, alto e muito alto com metas de LDL-c < 130, 100, 70 e 50 mg/dL, respectivamente. RESULTADOS: A média de idade foi de 65 anos, sendo 53% dos pacientes do sexo feminino. Do total, 1225 (56.2%) eram de risco muito alto, 900 (41.3%) alto, 50 (2.3%) intermediário e 5 (0.2%) de baixo risco. Trezentos e noventa e nove pacientes (18.3%) atingiram as metas de LDL-c estabelecidas pela diretriz, sendo 11.1%, 26.2%, 46% e 80% de cada faixa de risco, respectivamente. Destes, 74.5% dos pacientes de muito alto risco, 56.2% de alto risco, 86% de risco intermediário e 40% de baixo risco estavam em uso de estatinas na intensidade e doses preconizadas pela diretriz. Apenas 148 (6.8%) pacientes não usavam estatina. (AU)

An ergonomic approach to reorganize parking inspection agents' work productivity, health and safety in São Paulo, Brazil.

OBJECTIVE: The Traffic Engineering Company of the City of São Paulo (Brazil) observed a decrease in productivity, and an increase in sick leave, accidents and psychological distress among their parking inspection agents. To document this situation, qualitative research was undertaken to obtain an in-depth comprehension of work activity. PARTICIPANTS: Workers, managers and health and safety professionals contributed to the documentation of the problem and to the proposal of possible solutions. METHODS: Ergonomic work analysis focusing on real work activity, as well as interviews with individual or groups of stakeholders, were conducted. RESULTS: This research revealed that political-economic factors gradually contributed to: 1) an increasing work load; 2) growing fatigue throughout the day, increasing the workers' vulnerability to incidents and accidents and their tendency to react inappropriately to violence experienced on the street; and 3) excessive individual responsibility to manage dangerous situations. CONCLUSIONS: Recommendations to ameliorate the situation are proposed. These suggestions are discussed in terms of feasibility given the impact of macro social factors upon micro work activity, and the associated potential expansion of the ergonomist's role.

Population dynamics of genetically diverse Plasmodium falciparum lineages: community-based prospective study in rural Amazonia.

Temporal changes in the prevalence of antigenic variants in Plasmodium falciparum populations have been interpreted as evidence of immune-mediated frequency-dependent selection, but evolutively neutral processes may generate similar patterns of serotype replacement. Over 4 years, we investigated the population dynamics of P. falciparum polymorphisms at the community level by using 11 putatively neutral microsatellite markers. Plasmodium falciparum populations were less diverse than sympatric P. vivax isolates, with less multiple-clone infections, lower number of alleles per locus and lower virtual heterozygosity, but both species showed significant multilocus linkage disequilibrium. Evolutively neutral P. falciparum polymorphisms showed a high turnover rate, with few lineages persisting for several months in the population. Similar results had previously been obtained, in the same community, for sympatric P. vivax isolates. In contrast, the prevalence of the 2 dimorphic types of a major antigen, MSP-2, remained remarkably stable throughout the study period. We suggest that the relatively fast turnover of parasite lineages represents the typical population dynamics of neutral polymorphisms in small populations, with clear implications for the detection of frequency-dependent selection of polymorphisms.

Antidepressant-like and antinociceptive-like actions of 4-(4'-chlorophenyl)-6-(4''-methylphenyl)-2-hydrazinepyrimidine Mannich base in mice.

This study investigated the possible antidepressant and antinociceptive action of CPMPH Mannich base, as well as the involvement of serotonergic, dopaminergic, noradrenergic and opioid systems and the L-arginine-nitric oxide pathway in the antidepressant-like effect of CPMPH in the forced swimming test (FST) in mice. The immobility time in the FST was significantly reduced by CPMPH (0.1-10 mg/kg, i.p.), without accompanying changes in the ambulation in an open-field. CPMPH at high doses (i.p. or s.c. routes) produced a significant inhibition of acetic acid-induced writhing. The antidepressant-like effect of CPMPH (1 mg/kg, i.p.) in the FST was prevented by pre-treatment of mice with methysergide (2 mg/kg, i.p., a non-selective serotonin receptor antagonist), sulpiride (32 mg/kg, i.p., a D2 receptor antagonist) or yohimbine (1 mg/kg, i.p., an alpha2-adrenoceptor antagonist). In contrast, the antidepressant-like effect of CPMPH was not affected by pre-treatment (i.p.) with naloxone (1 mg/kg, a non-selective opioid receptor antagonist) or L-arginine (750 mg/kg, a nitric oxide precursor). The results demonstrate that CPMPH had an antidepressant-like action that appears to be mediated through its interaction with serotonergic, dopaminergic and noradrenergic systems.

Influence of physical exercise and sodium intake on arterial pressure and cardiac hypertrophy in rats.

Evidence shows that cardiac hypertrophy (CH) is a risk factor for many cardiovascular diseases. Several stimuli may cause CH-like manifestations and promote volume or pressure overload. Exercise-induced cardiac hypertrophy is an expected adaptation to regular exercise training. Salt intake has been shown to be the most important determinant of blood pressure in different populations. The purpose of the present work was to verify the influence of physical exercise and sodium intake on the blood pressure and myocardium. The study was performed on 36 rats divided into six groups: Group I (diet without salt overload), Group II (diet without salt overload and swimming), Group III (diet with 2.5% NaCl solution and swimming), Group IV (diet with 5% NaCl solution and swimming), Group V (diet with 2.5% NaCl solution without exercise), Group VI (diet with 5% NaCl solution without exercise). The arterial pressure was significantly lower in Group I when compared with Group IV. The ratio of cardiac mass/body mass was increased in Groups III and IV. In conclusion, there was evidence that exercise training and NaCl intake promotes arterial hypertension and cardiac hypertrophy.