Terapêuticas alternativas para redução do colesterol como fator de risco cardiovascular

Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas MonizAs Doenças Cardiovasculares (DCV) representam a maior causa de morte no mundo, incluindo Portugal. Incluem diversas patologias, sendo uma das principais causas a aterosclerose, um processo patológico que possui, entre outros, a hipercolesterolémia como fator de risco. Apesar do facto de alterações da dieta e do estilo de vida poderem reduzir de forma significativa o risco destas patologias, a prevalência e incidência das mesmas continuam a ser elevadas. Como tal, o tratamento é uma estratégia fundamental e, quanto mais abordagens terapêuticas houver, maior a probabilidade de controlarmos uma camada mais alargada da população, onde se incluem os indivíduos com comportamentos de risco e os pacientes com DCV. Nesse sentido, existe uma procura crescente de terapias alternativas às farmacológicas, uma vez que estas últimas são, na sua maioria, pertencentes à classe de fármacos estatinas, que podem produzir efeitos adversos significativos. O destaque das terapêuticas alternativas vai para os suplementos alimentares (SA), que aparentemente são mais bem tolerados que os fármacos, atuam por vários mecanismos e alguns apresentam resultados promissores. São, portanto, uma alternativa válida a explorar, existindo já vários estudos acerca do seu papel nas DCV. No entanto, nem todos apresentam resultados conclusivos e dos que o fazem, apenas os esteróis e estanóis vegetais, a levedura do arroz vermelho, as fibras solúveis e os ácidos gordos ómega-3 apresentam evidência científica de qualidade elevada. Ainda assim, é necessário que se façam mais ensaios clínicos para se entender melhor o papel destes SA na prevenção e tratamento destas patologias, com vista à definição das doses terapêuticas, margens de segurança, efeitos adversos e eventuais interações com medicamentos. O objetivo desta monografia é rever os vários mecanismos fisiopatológicos envolvidos nas DCV e analisar a evidência científica para o uso de SA na prevenção e tratamento das mesmas, com destaque para o seu papel na hipercolesterolémia

Palaeolithic diet decreases fasting plasma leptin concentrations more than a diabetes diet in patients with type 2 diabetes:A randomised cross-over trial

BACKGROUND: We have previously shown that a Palaeolithic diet consisting of the typical food groups that our ancestors ate during the Palaeolithic era, improves cardiovascular disease risk factors and glucose control compared to the currently recommended diabetes diet in patients with type 2 diabetes. To elucidate the mechanisms behind these effects, we evaluated fasting plasma concentrations of glucagon, insulin, incretins, ghrelin, C-peptide and adipokines from the same study. METHODS: In a randomised, open-label, cross-over study, 13 patients with type 2 diabetes were randomly assigned to eat a Palaeolithic diet based on lean meat, fish, fruits, vegetables, root vegetables, eggs and nuts, or a diabetes diet designed in accordance with current diabetes dietary guidelines during two consecutive 3-month periods. The patients were recruited from primary health-care units and included three women and 10 men [age (mean ± SD) 64 ± 6 years; BMI 30 ± 7 kg/m(2); diabetes duration 8 ± 5 years; glycated haemoglobin 6.6 ± 0.6 % (57.3 ± 6 mmol/mol)] with unaltered diabetes treatment and stable body weight for 3 months prior to the start of the study. Outcome variables included fasting plasma concentrations of leptin, adiponectin, adipsin, visfatin, resistin, glucagon, insulin, C-peptide, glucose-dependent insulinotropic polypeptide, glucagon-like peptide-1 and ghrelin. Dietary intake was evaluated by use of 4-day weighed food records. RESULTS: Seven participants started with the Palaeolithic diet and six with the diabetes diet. The Palaeolithic diet resulted in a large effect size (Cohen’s d = −1.26) at lowering fasting plasma leptin levels compared to the diabetes diet [mean difference (95 % CI), −2.3 (−5.1 to 0.4) ng/ml, p = 0.023]. No statistically significant differences between the diets for the other variables, analysed in this study, were observed. CONCLUSIONS: Over a 3-month study period, a Palaeolithic diet resulted in reduced fasting plasma leptin levels, but did not change fasting levels of insulin, C-peptide, glucagon, incretins, ghrelin and adipokines compared to the currently recommended diabetes diet. Trial registration: ClinicalTrials.gov NCT00435240 ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12933-016-0398-1) contains supplementary material, which is available to authorized users

Improving sperm quality and spermatogenesis through a bioactive marine compound : an experimental study

Dietary lipids may affect sperm membrane structure, fluidity and its susceptibility to oxidative phenomena which may lead to altered sperm viability and proper binding to eggs.Given the recently demonstrated beneficial effects of fish oil diets on turkey fertility and embryo viability, the aim of this study was to test a caviar-derived marine product on spermatogenesis and sperm quality. Sixty mice were divided into four different groups and fed for 3 weeks with normal chow (group A), added with LD-1227 at the dosage of either 5 mg/day (B1) or 10 mg/day (B2) while Group C received standard chow added with 10 mg of a DHArich mixture. At sacrifice tests/body weight ration and spermatogenesis was checked. No toxicity, histological sign or body or testes growth abnormality was noted, irrespective of the treatment. As compared to control, all supplements showed to increase sperm counting and motility although the effect of LD-1227 10 mg was significantly higher than DHA alone (p<0.05). Viability was improved by DHA (p<0.05) but not by low LD-1227 dosage while higher dosage performed better than DHA (p<0.05).Morphology was unaffected by any of the employed supplements. Taken altogether, these data suggest that LD-1227 has a remarkable effect on quali-quantitative parameters of spermiogenesis, some of them being more effective than high dosage DHA. These findings may prove to be of interest in clinical practice

The Human–Nature Relationship and Its Impact on Health: A Critical Review

Within the past four decades, research has been increasingly drawn toward understanding whether there is a link between the changing human–nature relationship and its impact on people’s health. However, to examine whether there is a link requires research of its breadth and underlying mechanisms from an interdisciplinary approach. This article begins by reviewing the debates concerning the human–nature relationship, which are then critiqued and redefined from an interdisciplinary perspective. The concept and chronological history of “health” is then explored, based on the World Health Organization’s definition. Combining these concepts, the human–nature relationship and its impact on human’s health are then explored through a developing conceptual model. It is argued that using an interdisciplinary perspective can facilitate a deeper understanding of the complexities involved for attaining optimal health at the human–environmental interface

The Puzzle of Altruism: Why do ‘Selfish Genes’ Behave so Unselfishly?

There are sound evolutionary and philosophical reasons for believing that human beings have a powerful innate disposition towards pure altruism—an altruism that is not a form of disguised selfishness, a survival strategy, or limited to those with whom we are closely genetically related. An overview of archaeological and anthropologic evidence suggests that the so-called 'environment of evolutionary adaptedness' was very different to the brutal, competitive struggle typically depicted by evolutionary psychologists. It is false to assume that competitiveness and selfishness are inevitable and fundamental human traits. An alternative view that altruism and co-operation are fundamental traits could more justifiably be drawn from archaeological and anthropological evidence. The philosophy of ‘panspiritism’ suggests that pure altruism is the result of the human capacity for empathy, which itself is the result of our fundamental interconnectedness

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum