811 resultados para ISCHEMIC-HEART-DISEASE


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Durante o tratamento radioterápico para tumores localizados na região torácica, parte do coração frequentemente é incluída no campo de tratamento e pode receber doses de radiação ionizante, significativas em relação à terapêutica. A irradiação do coração é capaz de causar importantes complicações cardíacas ao paciente, caracterizadas por alterações funcionais progressivas cerca de 10 a 20 anos após a exposição do órgão. Devido ao seu alto grau de contração e grande consumo energético, o tecido cardíaco é altamente dependente do metabolismo oxidativo que ocorre nas mitocôndrias. Danos as estas organelas podem levar ao decréscimo da produção de energia, tendo um impacto direto sobre a performance cardíaca. Ainda, ao interagir com as células, a radiação ionizante pode gerar uma série de eventos bioquímicos que conduzem a uma resposta celular complexa, em que muitas proteínas parecem estar envolvidas. Tendo em vista tais conhecimentos, o objetivo do estudo foi avaliar o aspecto ultraestrutural do tecido cardíaco, a bioenergética mitocondrial e a expressão diferencial de proteínas após irradiação. Os ensaios foram realizados em amostras de tecido cardíaco de ratos Wistar irradiados com dose única de 20 Gy direcionada ao coração. As análise tiveram início 4 e 32 semanas após irradiação. A análise ultraestrutural foi realizada através de microscopia eletrônica de transmissão. A respiração mitocondrial foi mensurada em oxígrafo, a partir das taxas de consumo de oxigênio pelas fibras cardíacas. A identificação de proteínas diferencialmente expressas foi investigada através de duas técnicas proteômicas: 2D-DIGE (2-D Fluorescence Difference Gel Electrophoresis) e uma abordagem label-free seguida de espectrometria de massas. Os resultados mostraram que os efeitos tardios da radiação incluem a degeneração das mitocôndrias e das unidades contráteis do tecido cardíaco, disfunções na cadeia respiratória mitocondrial e expressão diferencial de proteínas envolvidas no metabolismo energético de carboidratos, lipídeos e da fosfocreatina. De forma geral, o estudo mostrou que a irradiação cardíaca prejudica o processo de síntese energética, conduzindo a um déficit da taxa respiratória mitocondrial como efeito tardio. Tal evento pode culminar em disfunções mecânicas no coração, caracterizando o desenvolvimento de doenças cardíacas radioinduzidas.

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O papel dos polimorfismos genéticos da ECA (PGECA) na insuficiência cardíaca (IC) como preditor de desfechos clínicos e ecocardiográficos ainda não está estabelecido. É necessário identificar o perfil genotípico local para se observar se o impacto clínico desses genótipos é igual entre populações estrangeiras e a brasileira. O objetivo deste trabalho foi determinar a frequência das variantes do PGECA e sua relação com a evolução clínica de pacientes com IC de etiologia não isquêmica de uma população do Rio de Janeiro, utilizando desfechos clínicos, ecocardiográficos e do Seattle Heart Failure Model (SHFM).Para isso, realizou-se análise secundária de prontuários de 111 pacientes, acompanhados de forma prospectiva e retrospectiva, além da análise genética com identificação da variante do PGECA e sua classificação. Os pacientes foram acompanhados em média por 64,93,9 meses, tinham 59,51,3 (26-89) anos, predomínio do sexo masculino (60,4%) e da cor da pele branca (51,4 %), mas com alta prevalência de pretos (36 %). A distribuição do PGECA observada foi: 51,4 % DD, 44,1 % DI e apenas 4,5 % II. Hipertensão arterial foi a comorbidade mais frequentemente observada (70,3 %). O tratamento farmacológico estava bastante otimizado: 98,2 % em uso de betabloqueadores e 89,2 % em uso de inibidores da ECA ou losartana. Nenhuma das características clínicas ou do tratamento medicamentoso variou entre os grupos. Cerca de metade da coorte (49,5 %) apresentou fração de ejeção de VE (FEVE) ≤35 %. O diâmetro sistólico do VE (DSVE) final foi a única variável ecocardiográfica isolada significativamente diferente entre os PGECA: 59,21,8 DD x 52,31,9 DI x 59,25,2 (p=0,029). Quando analisadas de maneira evolutiva, todas as variáveis (FEVE, DSVE e DDVE) diferiram de maneira significativa entre os genótipos: p=0,024 para ∆FE, p=0,002 para ∆DSVE e p=0,021 para ∆DDVE. O genótipo DI se associou ao melhor parâmetro ecocardiográfico (aumento de FEVE e diminuição de diâmetros de VE), enquanto que o DD e II apresentaram padrão inverso. Os valores derivados do SHFM (expectativa de vida, mortalidade em um ano e mortalidade em cinco anos) não variaram de forma significativa entre os genótipos, mas notou-se um padrão com o DD associado a piores estimativas, DI a estimativas intermediárias e II a valores mais benignos. Não houve diferença significativa entre desfechos clínicos isolados (óbitos: p=0,552; internação por IC: p=0,602 e PS por IC: p=0,119) ou combinados (óbitos + internação por IC: p=0,559). Na análise multivariada, o peso alelo D foi preditor independente da variação do DSVE (p=0,023). Em relação aos preditores independentes de óbito + internação por IC, foram identificados classe funcional NYHA final (p=0,018), frequência cardíaca final (p=0,026) e uso de furosemida (p=0,041). Em suma, a frequência alélia e das variantes do PGECA foram diferentes da maioria do estudos internacionais. O alelo D foi associado de forma independente à pior evolução ecocardiográfica. Não houve diferenças significativas em relação aos parâmetros derivados do SHFM, embora o genótipo II pareça estar associado com o melhor perfil clínico. Por último, não houve diferenças em relação aos desfechos clínicos entre os PGECA.

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A periodontite é uma doença infecciosa, crônica e altamente prevalente causando uma resposta inflamatória. A infecção e a inflamação são consideradas a base etiológica para o desenvolvimento da aterosclerose. Recentes estudos indicam que a periodontite severa pode influenciar o aumento de marcadores inflamatórios e de disfunção endotelial associados com o aumento de risco da doença coronariana e o acidente vascular cerebral. Embora alguns estudos tenham sugerido esta associação, os reais efeitos do tratamento da doença periodontal sobre a rede complexa de marcadores envolvidos na aterosclerose são pouco conhecidos. O objetivo deste estudo foi avaliar o efeito da terapia periodontal nos biomarcadores inflamatórios (TNF-α, fibrinogênio, PCRus, INFγ, IL-1β, IL-6 e IL-10), perfil lipídico (CT, HDL, LDL, TG, oxLDL e anti-oxLDL) e função endotelial (IMT) das artérias carótidas. Um total de trinta e dois indivíduos saudáveis sistemicamente e afetados pela periodontite severa (16 mulheres, 16 homens; 51,87 anos de idade), incluindo 17 sujeitos para o grupo teste e 15 sujeitos para o grupo controle foram recrutados para o estudo. A ultrassonografia das artérias carótidas e os níveis séricos inflamatórios foram avaliados no início, 40 e 100 dias após o tratamento periodontal não-cirúrgico, comparando tempo e grupos. O tratamento periodontal resultou em significante redução dos parâmetros da doença periodontal. O grupo que recebeu tratamento mostrou decréscimos significativos de oxLDL (P<0.0001), anti-oxLDL (P<0,0001), TNF-α (P<0,0001), fibrinogênio (P=0,008), INFγ (P<0,0001), IL-1β (P<0,0001), IL-6 (P<0,0001), IMT (P=0,006) e significante aumento de IL-10 (P<0,0001) após 100 dias do tratamento periodontal comparando com grupo controle. Entretanto, os resultados não foram significativos para PCRu (P=0,109), colesterol total (P=0,438), HDL (P=0,119), LDL (P=0,425) e triglicerídeos (P=0,939). Com base nestes resultados, o tratamento da periodontite pode melhorar o perfil inflamatório e a função endotelial, sendo uma importante ferramenta adicional para a prevenção das doenças cardiovasculares.

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Access to robust and information-rich human cardiac tissue models would accelerate drug-based strategies for treating heart disease. Despite significant effort, the generation of high-fidelity adult-like human cardiac tissue analogs remains challenging. We used computational modeling of tissue contraction and assembly mechanics in conjunction with microfabricated constraints to guide the design of aligned and functional 3D human pluripotent stem cell (hPSC)-derived cardiac microtissues that we term cardiac microwires (CMWs). Miniaturization of the platform circumvented the need for tissue vascularization and enabled higher-throughput image-based analysis of CMW drug responsiveness. CMW tissue properties could be tuned using electromechanical stimuli and cell composition. Specifically, controlling self-assembly of 3D tissues in aligned collagen, and pacing with point stimulation electrodes, were found to promote cardiac maturation-associated gene expression and in vivo-like electrical signal propagation. Furthermore, screening a range of hPSC-derived cardiac cell ratios identified that 75% NKX2 Homeobox 5 (NKX2-5)+ cardiomyocytes and 25% Cluster of Differentiation 90 OR (CD90)+ nonmyocytes optimized tissue remodeling dynamics and yielded enhanced structural and functional properties. Finally, we demonstrate the utility of the optimized platform in a tachycardic model of arrhythmogenesis, an aspect of cardiac electrophysiology not previously recapitulated in 3D in vitro hPSC-derived cardiac microtissue models. The design criteria identified with our CMW platform should accelerate the development of predictive in vitro assays of human heart tissue function.

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Heart disease is one of the main factor causing death in the developed countries. Over several decades, variety of electronic and computer technology have been developed to assist clinical practices for cardiac performance monitoring and heart disease diagnosis. Among these methods, Ballistocardiography (BCG) has an interesting feature that no electrodes are needed to be attached to the body during the measurement. Thus, it is provides a potential application to asses the patients heart condition in the home. In this paper, a comparison is made for two neural networks based BCG signal classification models. One system uses a principal component analysis (PCA) method, and the other a discrete wavelet transform, to reduce the input dimensionality. It is indicated that the combined wavelet transform and neural network has a more reliable performance than the combined PCA and neural network system. Moreover, the wavelet transform requires no prior knowledge of the statistical distribution of data samples and the computation complexity and training time are reduced.

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Coronary heart disease (CHD)is a common cardiovascular disease in the elderly, is also a typical psychosomatic disease. Personality factors are very important in many psychological factors impacting on the prognosis of patients with CHD. The most influential personality factors to CHD are Type A and Type D personality. The previous research has shown that although Type A personality increased the prevalence of CHD, it cannot predict the development and prognosis after diagnosis. In contradict, Type D personality can predict prognosis. There is still no clinic-based or theory-based answer to the question: Why Type A personality cannot predict the outcome while Type D personality could predict the prognosis independently. The current research conducted a systematic investigation to the above question, which included one comparison study between CHD patients and control group, and four studies on reaction experiment and answered the question: why Type A personality cannot predict whereas Type D personality could effectively predict prognosis of CHD. The findings of the current research were: Type A and Type D personality influence CHD prognosis through different psychological mechanisms: both dimensions of Type D personality have direct influence on social support, whereas neither dimensions of Type A personality related to social support, directly of indirectly. Negative affection component of Type D personality significantly related to anxiety and depression, Social repression significantly related to anxiety but not depression. Both dimensions of Type A personality significantly related to anxiety but not depression. Neither under rest or diaphragmatic breathing conditions, Type A personality had no significant influence on vestibular autonomic reaction among healthy young males. Neither Type A nor Type D personality had significant influence on vestibular autonomic reaction among old CHD patients under rest condition. Type D personality predicted lower sympathetic excitation under rest condition, and lower cardiac vagal tone under diaphragmatic breathing condition among healthy young males. When actively reacted to stimuli (math calculation) under rest condition, Type A personality increased sympathetic excitation among healthy young males. When actively reacted to stimuli (math calculation) under diaphragmatic breathing condition, Type A personality increased cardiac vagal tone among the same group of subjects. When actively reacted to stimuli under neither condition, Type D personality showed no significant influence on vestibular autonomic reaction among young males. When passively reacted to stimuli under neither condition, Type A personality showed no significant influence on vestibular autonomic reaction among young males. When passively stimulated followed rest, Type D personality increased sympathetic excitation and decreased cardiac vagal tone among young males. When passively stimulated followed diaphragmatic breathing, Typed showed no significant influence on vestibular autonomic reaction among young males. The above results indicated that Type A and Type D personalities had different psychological mechanisms to the outcome of CHD treatment: neither dimensions of Type A personality had direct or indirect effects on social support; both dimensions of Type D personality had direct and indirect effects on social support. Negative affection component of Type D personality significantly related to anxiety and depression, Social repression significantly related to anxiety but not depression. Both dimensions of Type A personality significantly related to anxiety but not depression. Social support positively related to the outcome after CHD treatment. The biological mechanisms of Type A and Type B personality to CHD prognosis differed in the following ways: Type A personality increased sympathetic excitation when actively stimulated, but had no influence when passively stimulated among young male subjects. When passively stimulated after rest, Type D personality predicted high sympathetic excitation and low cardiac vagal tone among young males, but not vestibular autonomic reaction among young males. Key words: Type A personality, Type D personality, Coronary Heart Disease (CHD), Prognosis, Psychobiological Mechanisms

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In order to study the role of inherited factors and Type A Behavior Pattern (TABP) in the development of CHD, the present study chose the angiotensin I-converting enzyme (ACE) gene as the target gene, and investigated the associations of TABP, the polymorphism of ACE gene with susceptibility to development of CHD in the healthy population and CHD patients from Northern China. 1. Correlation Analysis Between TABP and serum level of ACE in Chinese healthy individuals TABP and serum of ACE were determined in 137 Chinese healthy individuals. The results showed that there was a significant correlation between the scores of CH in TABP invertory and the serum level of ACE. 2 The distribution charicteristics of ACE gene polymorphism frequencies and association with serum level of ACE in Chinese healthy individuals population The polymorphism of ACE gene and serum of ACE were determined in 137 Chinese healthy individuals. The results showed that: the ethnic differences in I/D polymorphism of ACE gene are obvious; deletion polymorphism of the ACE gene is associated with serum ACE level. 3. The relationship between insertion/deletion polymorphism of ACE gene and CHD in a Chinese population I/D polymorphism in intron 16 of the ACE gene was determined by polymerase chain reaction(PCR) in a study of 109 patients with CHD. The results showed: The frequencies of DD genotype(0.39) and D allele(0.63) were higher among the CHD group than among the control subjects(0.12 and 0.42 respectively, P < 0.01). Furthermore, MI and multivessel disease was more strongly associated with (P < 0.01). It is indicated that D allele and DD gentype of ACE might be an important risk factor for CHD, especially for MI or multivessel disease in Chinese population. 4. Correlation Analysis Between Type A Behavior Pattern and the Polymorphism of ACE Gene The polymorphism of ACE gene and type A behavior pattern (TABP) survey were determined in 291 Chinese healthy individuals. The result showed that the higher frequency of rare D allele of an insertion/deletion (I/D) polymorphism of the angiotensin I-converting enzyme (ACE) gene was found in type A behavior individuals compared with type B behavior individuals in 291 healthy individuals; there was a significant correlation between the scores of CH in TABP invertory and DD genotype of the ACE gene. It is suggested that the behavioral attributes of competitiveness, achievement striving, hostility, being irritated easily and impatience may be associated with heredity. 5. Correlation Analysis Between Angiotensin I-Converting Enzyme Gene Polymorphism, Type A Behavior Pattern and Coronary Heart Disease in Chinese The polymorphism of ACE gene and type A behavior pattern (TABP) survey were determined in 109 patients with CHD. The results showed the development of coronary heart disease(CHD) is influenced mainly by the behavioral attributes of competitiveness, achievement striving, hostility, being irritated easily and impatience; the deletion polymorphism of ACE gene may be play a important role in the process of it. 6. Correlation Analysis Between Type A Behavior Pattern Core Components and the Polymorphism of ACE Gene The polymorphism of ACE gene and type A behavior pattern (TABP) survey were determined in1306 Chinese healthy individuals. The results showed that there was a significant correlation between the scores of CH in TABP invertory and DD genotype of the ACE gene. Furthermore, the behavioral attributes of hostility, being irritated easily and impatience may be associated with heredity. At the end of this research, in terms of theory, the research approaches of TABP and the factors influenced the relationship between TABP and CHD were explored and discussed. Furthermore, several new opinions were put forward.

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas

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Introduction: There is accumulating evidence of an increased risk of cardiovascular morbidity and mortality in rheumatoid arthritis patients. A combination of both traditional cardiovascular risks and rheumatoid specific factors appear to be responsible for driving this phenomenon. Rheumatoid arthritis has been an orphan of cardiologists in the past and rheumatologists themselves are not good at CVD screening. Identifying the extent of preclinical atherosclerosis in RA patients will help us to appreciate the magnitude of this serious problem in an Irish population. Methods: We undertook a cross-sectional study of 63 RA patients and 48 OA controls and compared the 2 groups with respect to 1) traditional CV risks factors, 2) serum biomarkers of inflammation, including CRP, TNFα, IL6 and PAI-1, 3) carotid intima-media thickness (cIMT), carotid plaque and ankle-brachial index (ABI) as markers of pre-clinical atherosclerosis, 4) biochemical and ultrasonic measures of endothelial dysfunction and 5) serum and echocardiographic measures of diastolic dysfunction. Within the RA group, we also investigated for associations between markers of inflammation, subclinical atherosclerosis and diastolic dysfunction. Results: Prevalence of traditional CV risks was similar in the RA and OA groups. A number of biomarkers of inflammation were significantly higher in the RA group: CRP, fibrinogen, IL- 2, -4, -6, TNFα. PAI-1, a marker of thrombosis, correlated with disease activity and subclinical atherosclerosis in RA patients. With regard to subclinical atherosclerosis measures, RA patients had a significantly lower ABI than OA patients. Carotid plaque and cIMT readings were similar in RA and OA patients. Assessment of endothelial function revealed that RA patients had significantly higher concentrations of adhesion molecules, in particular sero-positive RA patients and RA smokers. Adhesion molecule concentrations were associated with markers of diastolic dysfunction in RA. Urine PCR, another marker of endothelial dysfunction also correlated with diastolic dysfunction in RA. Assessment of endothelial function with flow mediated dilatation (FMD) found no difference between the RA and OA groups. Disease activity scores in RA patients were associated with endothelial dysfunction, as assessed by FMD. Conclusions: We did not find significant differences in measures of subclinical atherosclerosis, flow mediated dilatation or diastolic function between RA and OA patients. This is most likely in part due to the fact that there is increasing evidence that OA has an inflammatory component to its pathogenesis and is associated with metabolic syndrome and increased CV risk. We reported a significant association between urinary PCR and measures of diastolic dysfunction. Urinary PCR may be a useful screening tool for diastolic dysfunction in RA. The association between RA disease activity and measures of vascular function supports the theory that the excess cardiovascular burden in RA is linked to uncontrolled inflammation.

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This study investigates the effect of serious health events including new diagnoses of heart attacks, strokes, cancers, chronic lung disease, chronic heart failure, diabetes, and heart disease on future smoking status up to 6 years postevent. Data come from the Health and Retirement Study, a nationally representative longitudinal survey of Americans aged 51-61 in 1991, followed every 2 years from 1992 to 1998. Smoking status is evaluated at each of three follow-ups, (1994, 1996, and 1998) as a function of health events between each of the four waves. Acute and chronic health events are associated with much lower likelihood of smoking both in the wave immediately following the event and up to 6 years later. However, future events do not retrospectively predict past cessation. In sum, serious health events have substantial impacts on cessation rates of older smokers. Notably, these effects persist for as much as 6 years after a health event.

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Relationships between aging, disease risks, and longevity are not yet well understood. For example, joint increases in cancer risk and total survival observed in many human populations and some experimental aging studies may be linked to a trade-off between cancer and aging as well as to the trade-off(s) between cancer and other diseases, and their relative impact is not clear. While the former trade-off (between cancer and aging) received broad attention in aging research, the latter one lacks respective studies, although its understanding is important for developing optimal strategies of increasing both longevity and healthy life span. In this paper, we explore the possibility of trade-offs between risks of cancer and selected major disorders. First, we review current literature suggesting that the trade-offs between cancer and other diseases may exist and be linked to the differential intensity of apoptosis. Then we select relevant disorders for the analysis (acute coronary heart disease [ACHD], stroke, asthma, and Alzheimer disease [AD]) and calculate the risk of cancer among individuals with each of these disorders, and vice versa, using the Framingham Study (5209 individuals) and the National Long Term Care Survey (NLTCS) (38,214 individuals) data. We found a reduction in cancer risk among old (80+) men with stroke and in risk of ACHD among men (50+) with cancer in the Framingham Study. We also found an increase in ACHD and stroke among individuals with cancer, and a reduction in cancer risk among women with AD in the NLTCS. The manifestation of trade-offs between risks of cancer and other diseases thus depended on sex, age, and study population. We discuss factors modulating the potential trade-offs between major disorders in populations, e.g., disease treatments. Further study is needed to clarify possible impact of such trade-offs on longevity.

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BACKGROUND: Coronary artery bypass grafting (CABG) is often used to treat patients with significant coronary heart disease (CHD). To date, multiple longitudinal and cross-sectional studies have examined the association between depression and CABG outcomes. Although this relationship is well established, the mechanism underlying this relationship remains unclear. The purpose of this study was twofold. First, we compared three markers of autonomic nervous system (ANS) function in four groups of patients: 1) Patients with coronary heart disease and depression (CHD/Dep), 2) Patients without CHD but with depression (NonCHD/Dep), 3) Patients with CHD but without depression (CHD/NonDep), and 4) Patients without CHD and depression (NonCHD/NonDep). Second, we investigated the impact of depression and autonomic nervous system activity on CABG outcomes. METHODS: Patients were screened to determine whether they met some of the study's inclusion or exclusion criteria. ANS function (i.e., heart rate, heart rate variability, and plasma norepinephrine levels) were measured. Chi-square and one-way analysis of variance were performed to evaluate group differences across demographic, medical variables, and indicators of ANS function. Logistic regression and multiple regression analyses were used to assess impact of depression and autonomic nervous system activity on CABG outcomes. RESULTS: The results of the study provide some support to suggest that depressed patients with CHD have greater ANS dysregulation compared to those with only CHD or depression. Furthermore, independent predictors of in-hospital length of stay and non-routine discharge included having a diagnosis of depression and CHD, elevated heart rate, and low heart rate variability. CONCLUSIONS: The current study presents evidence to support the hypothesis that ANS dysregulation might be one of the underlying mechanisms that links depression to cardiovascular CABG surgery outcomes. Thus, future studies should focus on developing and testing interventions that targets modifying ANS dysregulation, which may lead to improved patient outcomes.

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Climate change induced by anthropogenic warming of the earth's atmosphere is a daunting problem. This review examines one of the consequences of climate change that has only recently attracted attention: namely, the effects of climate change on the environmental distribution and toxicity of chemical pollutants. A review was undertaken of the scientific literature (original research articles, reviews, government and intergovernmental reports) focusing on the interactions of toxicants with the environmental parameters, temperature, precipitation, and salinity, as altered by climate change. Three broad classes of chemical toxicants of global significance were the focus: air pollutants, persistent organic pollutants (POPs), including some organochlorine pesticides, and other classes of pesticides. Generally, increases in temperature will enhance the toxicity of contaminants and increase concentrations of tropospheric ozone regionally, but will also likely increase rates of chemical degradation. While further research is needed, climate change coupled with air pollutant exposures may have potentially serious adverse consequences for human health in urban and polluted regions. Climate change producing alterations in: food webs, lipid dynamics, ice and snow melt, and organic carbon cycling could result in increased POP levels in water, soil, and biota. There is also compelling evidence that increasing temperatures could be deleterious to pollutant-exposed wildlife. For example, elevated water temperatures may alter the biotransformation of contaminants to more bioactive metabolites and impair homeostasis. The complex interactions between climate change and pollutants may be particularly problematic for species living at the edge of their physiological tolerance range where acclimation capacity may be limited. In addition to temperature increases, regional precipitation patterns are projected to be altered with climate change. Regions subject to decreases in precipitation may experience enhanced volatilization of POPs and pesticides to the atmosphere. Reduced precipitation will also increase air pollution in urbanized regions resulting in negative health effects, which may be exacerbated by temperature increases. Regions subject to increased precipitation will have lower levels of air pollution, but will likely experience enhanced surface deposition of airborne POPs and increased run-off of pesticides. Moreover, increases in the intensity and frequency of storm events linked to climate change could lead to more severe episodes of chemical contamination of water bodies and surrounding watersheds. Changes in salinity may affect aquatic organisms as an independent stressor as well as by altering the bioavailability and in some instances increasing the toxicity of chemicals. A paramount issue will be to identify species and populations especially vulnerable to climate-pollutant interactions, in the context of the many other physical, chemical, and biological stressors that will be altered with climate change. Moreover, it will be important to predict tipping points that might trigger or accelerate synergistic interactions between climate change and contaminant exposures.

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Familial hypercholesterolemia (FH) is a genetic disorder characterized by abnormally high concentrations of low-density lipoprotein-cholesterol (LDLcholesterol) in the blood that can contribute to heart disease. FH can result from a defect in the gene for the LDL receptor (LDL-R). FH patients lacking functional LDL-R may benefit from viral-mediated transfer of a functional copy of the open reading frame (ORF) of the LDL-R. Since a recombinant adeno-associated virus (rAAV) is not immunogenic and can be mass-produced, it shows promise for gene therapy applications. AAV6 and AAV8 have been shown to specifically transduce hepatocytes in several species, which normally remove the majority of LDL-cholesterol from the blood via LDL-R-mediated endocytosis. Because of the potential of rAAV to treat FH by delivery of a correct LDL-R ORF to hepatocytes, the liver specificity of these two AAV serotypes was evaluated. Additionally, rabbits were chosen as the animal model for this study because a specific strain of rabbits, Watanabe heritable hyperlipidemic (WHHL), adequately mimics the pathology of FH in humans. Exposure of rabbit liver to rAAV with the marker LacZ and subsequent inspection of liver tissue showed that AAV8 transduced rabbit liver more efficiently than AAV6. To assess the feasibility of producing a rAAV capable of transferring the LDL-R ORF to rabbit hepatocytes in vivo, rAAV8-LDL-R was mass-produced by a baculovirus system in suspension grown insect cells.

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The objective of this cross-sectional study was a comprehensive nutrition and health assessment to provide a basis for future intervention strategies for an elderly population attending a day-care centre. Socio-demographic, health and 24-hour recall dietary intake questionnaires were administered and anthropometric and biochemical measurements taken. The results indicate that the majority of respondents had an income of between R501 and R1 000 (South African rand) per month and most of them reported an occasional lack of funds to meet basic household needs, confirming the presence of food insecurity. Daily dietary intakes (mean [+ or -] Standard Deviation [SD]) of the women were 5 395 [+ or -] 2 946 kJ energy, 47 [+ or -] 27 g protein, 28 [+ or -] 21 g fat and 196 [+ or -] 123 g carbohydrates compared to 8 641 [+ or -] 3 799 kJ, 86 [+ or -] 48 g, 49 [+ or -] 32 g and 301 [+ or -] 139 g of the men, respectively. The majority (83.6%) of the women were overweight (body mass index [BMI] [greater than or equal to] 25) or obese (BMI [greater than or equal to] 30) whilst 78% had a mid-upper arm circumference (MUAC) of [greater than or equal to] 21.7 cm. Mean intakes of micronutrients were low in comparison to reference standards and serum zinc levels were suboptimal. Obesity, hypertension and raised total serum cholesterol levels indicated an increased risk for coronary heart disease. It can be concluded that a low income, household food insecurity and risk factors associated with malnutrition and non-communicable diseases were prevalent in this elderly population. OPSOMMING Die doelwit van hierdie dwarssnitstudie was ‘n omvattende bepaling van voeding- en gesondheidstatus om as basis te dien vir toekomstige intervensiestrategieë vir ’n groep bejaardes wat ’n dagsentrum besoek. Sosiodemografiese, gesondheid- en 24-uur herroep-dieetinname vraelyste is voltooi en antropometriese en biochemiese metings is geneem. Die resultate het bevestig dat die meerderheid respondente ‘n maandelikse inkomste van tussen R501 en R1 000 (Suid-Afrikaanse rand) gehad het. Die meeste het ‘n geldtekort vir basiese huishoudelike behoeftes gerapporteer wat dui op huishoudelike voedselinsekuriteit. Daaglikse dieetinnames (gemiddeld±standaardafwyking [SA]) van die vroue was onderskeidelik 5 395±2 946 kJ energie, 47±27 g proteïen, 28±21 g vet en 196±123 g koolhidrate in vergelyking met 8 641±3 799 kJ, 86±48 g, 49±32 g en 301±139 g vir die mans. Die meerderheid (83.6%) van die vroue was oorgewig (liggaamsmassa-indeks [LMI] >25) of vetsugtig (LMI > 30) en 78% het ’n middel-bo-armomtrek (MUAC) van > 21.7 cm gehad. Gemiddelde mikronutriëntinnames was laag in vergelyking met die verwysingstandaarde en serumsink was suboptimaal. Vetsug, hipertensie en verhoogde totale serumcholesterolvlakke het op ‘n verhoogde risiko van kardiovaskulêre siekte gedui. Die resultate het dus bewys dat lae inkomste, huishoudelike voedselinsekuriteit en die risikofaktore wat met wanvoeding en leefstylsiektes geassosieer word, teenwoordig was.