Long-term environmental modifications affect BDNF concentrations in rat hippocampus, but not in serum.

The role of mBDNF on the beneficial effects of cognitive stimulation on the brain remains controversial, as well as the potential of peripheral mBDNF as a biomarker of environmental effects on its central status. We investigated the effect of different environmental conditions on recognition memory, proBDNF, mBDNF and synaptophysin levels in the hippocampus, and on mBDNF levels in blood. Male Wistar rats (6 and 17 months-old) were assigned to cognitively enriched (EE), standard (SE) and impoverished (IE) environmental conditions for twelve weeks. Novel object recognition was performed at week 10. When the animals were 9 and 20-months old, hippocampus was collected for mBDNF, proBDNF and synaptophysin analysis; serum was analyzed for mBDNF levels. The cognitively EE improved recognition memory, resulted in a trend to increased hippocampal mBDNF and augmented synaptophysin levels. Accordingly, hippocampal mBDNF, proBDNF and synaptophysin were significantly higher in EE than IE animals. Hippocampal mBDNF was positively correlated to proBDNF, cellular and behavioral plasticity markers. No effect of age was seen on the studied variables. Moreover, no significant effects of EE or IE on serum mBDNF were observed. Serum mBDNF also failed to correlate with hippocampal mBDNF, proBDNF and with the cellular and behavioral plasticity markers. These findings indicate that mBDNF is involved in neuronal and behavioral plasticity mechanisms induced by cognitively enriched environments, and that peripheral mBDNF may not always be a reliable biomarker of the effects of environmental settings on central mBDNF and plasticity, which is of special interest from a translational research perspective.

Social isolation and social support at adulthood affect epigenetic mechanisms, brain-derived neurotrophic factor levels and behavior of chronically stressed rats.

Epigenetic modulation of brain-derived neurotrophic factor (BDNF) provides one possible explanation for the dysfunctions induced by stress, such as psychiatric disorders and cognitive decline. Interestingly, social support can be protective against some of these effects, but the mechanisms of social buffering are poorly understood. Conversely, early isolation exacerbates the responses to stressors, although its effects in adulthood remain unclear. This study investigated the effects of social isolation and social buffering on hippocampal epigenetic mechanisms, BDNF levels and behavioral responses of chronically stressed young adult rats. Male Wistar rats (3 months) were assigned to accompanied (paired) or isolated housing. After one-month half of each group was submitted to a chronic unpredictable stress (CUS) protocol for 18 days. Among accompanied animals, only one was exposed to stress. Behavioral analysis encompassed the Open field, plus maze and inhibitory avoidance tasks. Hippocampal H3K9 and H4K12 acetylation, HDAC5 expression and BDNF levels were evaluated. Isolated housing increased HDAC5 expression, decreased H3K9 and H4K12 acetylation, reduced BDNF levels, and impaired long-term memory. Stress affected weight gain, induced anxiety-like behavior and decreased AcK9H3 levels. Interactions between housing conditions and social stress were seen only for HDAC5 expression, which showed a further increase in the isolated + CUS group but remained constant in accompanied animals. In conclusion, social isolation at adulthood induced epigenetic alterations and exacerbated the effects of chronic stress on HDAC5. Notwithstanding, social support counteracted the adverse effects of stress on HDAC5 expression.

Acesso vascular para hemodiálise / Hemodialysis vascular hemodialysis vascular access

Introdução: A Doença Renal Crônica (DRC) acomete um grande número de pacientes em todo o mundo, sendo a hemodiálise um dos recursos terapêuticos mais frequentes para as fases mais avançadas de falência renal. Uma vez que o acesso vascular é essencial para a terapia, o presente artigo tem como objetivo revisar a literatura relacionada às indicações, técnica e complicações dos acessos temporários e permanentes. Métodos: A busca nas bases de dados Pubmed e LILACS foi realizada através da combinação de termos relacionados à hemodiálise ou diálise renal, acesso vascular e vasos sanguíneos. Foram selecionados 20 artigos conforme os critérios de inclusão e de exclusão e adequação ao tema proposto. Resultados: Os acessos temporários são o cateter de Shilley e o permcath. O primeiro se destina a situações agudas, inserido preferencialmente na veia jugular direita e tem a infecção como principal complicação. O permcath proporciona um período mais longo de utilização, com implante subcutâneo preferencialmente em veia jugular interna direita, tendo como principal complicação a punção arterial inadvertida. A fístula representa o acesso vascular definitivo, sendo o acesso de primeira escolha para pacientes que serão submetidos à hemodiálise por longo prazo. Suas maiores complicações são infecção, sangramento e alteração de fluxo sanguíneo arterial. Conclusão: Acesso vascular para hemodiálise é fundamental para instituição e manutenção da terapia. Dentre as opções atuais, o tempo de permanência, as potenciais complicações e as condições do pacientes guiarão a escolha.

Introduction: Chronic Kidney Disease (CKD) affects a large number of patients worldwide, with hemodialysis being one of the most frequent therapeutic resources for the more advanced phases of renal failure. As vascular access is paramount for this therapy, we aimed reviewing the literature regarding indications, technique and complications of temporary and permanent vascular accesses for hemodialysis. Methods: Pubmed and LILACS databases were searched combining terms refered to hemodialysis or renal dialysis, vascular access and blood vessels. It were selected 20 articles according inclusion and exclusion criteria as well as related to the proposed theme. Results: Temporary accesses are Shilley catheter and permcath. Shilley is indicated for acute situations, inserted preferably in the right jugular vein and the main complication is infection. Permcath allows a longer period of use, subcutaneously implanted preferably in the right internal jugular vein. The main complication is arterial puncture. Arteriovenous fistula represents the definitive vascular access, constituing the first choice for patients needing long term hemodialysis. The technique is based on the anastomosis between the artery and vein walls or between its extremities and the main complication is related to infection, bleeding and decreased artery blood flow. Conclusion: Hemodialysis vascular access is paramount in order to start and maintain the therapy. The option will be guided by therapy length, complications and clinical conditions.

Cessação do tabagismo: revisão dos diferentes métodos / Tobacco cessation: a review of different methods

Objetivos: O artigo revisa os métodos de tratamento atualmente mais indicados para cessação do tabagismo. Métodos: Uma busca nas bases Medline/Pubmed e Lilacs foi realizada com termos referentes a cessação do tabagismo, produtos utilizados para cessar o tabagismo e taxa de abstinência. Foram selecionadas revisões sistemáticas e ensaios clínicos em texto completo, publicados nos últimos 5 anos, em língua inglesa ou portuguesa, tendo como participantes humanos adultos. Após análise foram incluídos 10 artigos para revisão. Resultados: Em relação à terapia comportamental, o emprego de aconselhamento telefônico teve pior desfecho em comparação aos contatos pessoais (p=0.01) e à combinação de ambos (p=0.01). A abordagem proativa favorece a taxa de abstinência (p<0.001). O incentivo financeiro, no entanto, não teve efeitos sobre a taxa de abstinência a longo prazo (p=0.95). Quanto à terapia farmacológica, a bupropiona (OR 1.84) e a vareniclina (OR 2.88), isoladamente, aumentaram a taxa de abstinência comparadas ao placebo, tendo a vareniclina demonstrado resultados superiores (OR 1.57). A Terapia de Reposição Nicotínica combinada com bupropiona ou nortriptilina não resultou em aumento na taxa de abstinência quando comparada à Terapia de Reposição de Nicotina em monoterapia (OR 0.99). A nortriptilina também aumentou a taxa de abstinência, com poucos efeitos adversos (RR 2.03). A associação de bupropiona e vareniclina gerou maior taxa de abstinência em um mês comparada à monoterapia com vareniclina (p=0.029). Não houve diferença significativa entre Terapia de Reposição de Nicotina por goma comparada ao adesivo transdérmico em relação à redução do tabagismo (p>0.05). Conclusões: Diversos medicamentos são eficazes e estão disponíveis para auxílio à cessação do tabagismo. Deve-se avaliar o contexto clínico de cada paciente, ofertando a terapia mais adequada a cada caso. Abordagens proativas e motivacionais, além da facilitação do acesso aos recursos de tratamento também melhoram as taxas de abstinência.

Aims: This article aims to present a review of tobacco cessation methods currently most indicated in order to update health professionals. Methods: It was performed a search in Medline/Pubmed and Lilacs using terms referring to smoking cessation, smoking cessation products and Abstinence Rate. Systematic reviews and clinical trials in full text articles, published in the last five years in English or Portuguese, having human adults as participants, were selected. After analysing adequacy to the subject, 10 articles were included to be reviewed. Results: Regarding to non-pharmacological therapies, telephone counselling showed worse results in comparison to personal therapy (p=0.01) and also comparing to the combination of them (p=0.01). Besides, a proactive approach enhances abstinence rate when compared to usual approach (p<0.001). Cash incentive did not result in a higher abstinences rates in long term when compared to control group (p=0.95). In relation to pharmacological therapy, bupropion (OR 1.84) and varenicline (OR 2.88), separately, increased abstinence rate in comparison to placebo, although varenicline showed superior results (OR 1.57). Nicotine Replacement Therapy in combination with bupropion or nortriptilin did not result in a higher abstinence rate when compared to Nicotine Replacement Therapy as monotherapy (OR 0.99). Nortriptilin enhances abstinence rate, with little adverse events (RR 2.03). Combination of bupropion and varenicline resulted in an increased abstinence rate in one month in comparison to varenicline as single therapy (p=0.029). There was no significant difference between Nicotine Replacement Therapy with nicotine gum and patch in relation to smoking reduction (p>0.05). Conclusions: Many medications were found to be effective and are available for smoking cessation. Clinical context of each patient should be evaluated, offering the most appropriate therapy. Proactive approaches and simplified access to resources also improve abstinence rates.

Exercício físico e diabetes mellitus: explorando efeitos e implicações / Physical exercise and diabetes mellitus: exploring effects and implications

Objetivos: Este estudo tem como objetivo realizar uma revisão da literatura sobre a efetividade do exercício físico no controle glicêmico de indivíduos portadores de Diabetes Mellitus (DM). Métodos: A revisão foi conduzida no mês de maio de 2018 nas bases Pubmed/Medline e Lilacs com o cruzamento dos termos "Diabetes Mellitus" e "Exercise", sendo selecionadas apenas publicações de textos completos - guidelines ou revisões - escritos em língua inglesa ou língua portuguesa, considerando participantes humanos adultos durante o período de 2016 até o momento da busca. Resultados: Sete revisões sistemáticas que examinaram o efeito de atividade física em pacientes diabéticos estavam de acordo com os critérios de inclusão. Técnicas de mudança no comportamento como o acompanhamento com profissionais da saúde e educação acerca da doença foram intervenções associadas a uma maior adesão à prática de atividade física, assim como dieta e exercício físico trouxeram melhorias ao controle glicêmico. Conclusão: O estudo identifica que a prescrição de exercício físico, sendo este de moderada à alta intensidade, é um dos pilares para a melhora na qualidade de vida de indivíduos diabéticos. Caso a atividade física seja adequada à realidade do paciente, haverá a regressão não só dos indicadores do DM, tal como o nível de Hemoglobina Glicosilada (Hb1AC), mas também dos fatores de risco, como, por exemplo, doenças cardiovasculares.

Aims: This study aims to review the effect of physical exercise in the glycemic control in individuals with Diabetes Mellitus (DM). Methods: The review was conducted in May 2018, using the terms "Diabetes Mellitus" and "Exercise" in two electronic databases: Pubmed/Medline and Lilacs. There were only included full-term studies, such as guidelines or reviews, written in english and in portuguese, considering human adults participants during the period between 2016 and May 2018. Studies that did not meet this criteria were not picked. Results: Seven systematic reviews examining the effect of physical activity in diabetic patients met the eligibility criteria. Behavioral change techniques such as follow-up with health professionals and education about the disease were interventions associated with a better adherence to physical activity, as well as diet and physical exercise had improvements in glycemic control. Conclusion: The study identifies that the prescription of physical exercise, from moderate to high intensity, improves the quality of life in people with DM. If the physical activity is adequate to the patient's particularities, there will be decrease not only of diabetes indicators, such as glycosylated hemoglobin (HbA1C), but also of the risk factors, as cardiovascular diseases.