Number of risky lifestyle behaviors and breast cancer risk

Background Lifestyle factors are associated with overall breast cancer risk, but less is known about their associations, alone or jointly, with risk of specific breast cancer subtypes. Methods We conducted a case–control subjects study nested within a cohort of women who participated in the Norwegian Breast Cancer Screening Program during 2006–2014 to examine associations between risky lifestyle factors and breast cancer risk. In all, 4402 breast cancer cases subjects with information on risk factors and hormone receptor status were identified. Conditional logistic regression was used to estimate odds ratios (ORs), with 95% confidence intervals (CIs), in relation to five risky lifestyle factors: body mass index (BMI) of 25 kg/m² or greater, three or more glasses of alcoholic beverages per week, ever smoking, fewer than four hours of physical activity per week, and ever use of menopausal hormone therapy. Analyses were adjusted for education, age at menarche, number of pregnancies, and menopausal status. All statistical tests were two-sided. Results Compared with women with no risky lifestyle behaviors, those with five had 85% (OR = 1.85, 95% CI = 1.42 to 2.42, Ptrend  .18 for all). Conclusions Number of risky lifestyle factors was positively associated with increased risk for luminal A–like and luminal B–like HER2-positive breast cancer

Photosynthetic quantum efficiency in south‐eastern Amazonian trees may be already affected by climate change

Tropical forests are experiencing unprecedented high‐temperature conditions due to climate change that could limit their photosynthetic functions. We studied the high‐temperature sensitivity of photosynthesis in a rainforest site in southern Amazonia, where some of the highest temperatures and most rapid warming in the Tropics have been recorded. The quantum yield (F v /F m ) of photosystem II was measured in seven dominant tree species using leaf discs exposed to varying levels of heat stress. T 50 was calculated as the temperature at which F v /F m was half the maximum value. T 5 is defined as the breakpoint temperature, at which F v /F m decline was initiated. Leaf thermotolerance in the rapidly warming southern Amazonia was the highest recorded for forest tree species globally. T 50 and T 5 varied between species, with one mid‐storey species, Amaioua guianensis , exhibiting particularly high T 50 and T 5 values. While the T 50 values of the species sampled were several degrees above the maximum air temperatures experienced in southern Amazonia, the T 5 values of several species are now exceeded under present‐day maximum air temperatures

Fatores de risco e complicações em hipertensos/diabéticos de uma regional sanitária do nordeste brasileiro

Objetivou-se com este estudo identificar os fatores de risco e a complicações associadas em usuários com hipertensão/diabetes, cadastrados no HIPERDIA da Secretaria Executiva Regional VI em Fortaleza, CE. O estudo documental analítico abordou 2.691 pessoas. Do total, 73,6% eram mulheres; 44,6% tinham 60-79 anos, com média de 60,8 anos; 87,4% eram brancos, amarelos ou pardos; 63,7% tinham até oito anos de estudo; 79,7% não eram fumantes; 56,6% sedentários; 59,6% apresentavam sobrepeso/obesidade; 48,4% possuíam antecedente familiar de doença cardiovascular. Verificou-se associação entre sedentarismo e sobrepeso/obesidade com diabéticos e diabéticos hipertensos; antecedente familiar de doença cardiovascular com os hipertensos e diabéticos hipertensos; acidente vascular encefálico, doença arterial coronariana e insuficiência renal crônica com hipertensos e diabéticos hipertensos; infarto e acidente vascular encefálico com diabéticos. O antecedente familiar cardiovascular associou-se com doença arterial coronariana e infarto. Evidenciou-se a presença relevante de fatores de risco e complicações, destacando a necessidade da educação em saúde com os usuários

Influence of ischemic core muscle fibers on surface depolarization potentials in superfused cardiac tissue preparations: a simulation study

Thin-walled cardiac tissue samples superfused with oxygenated solutions are widely used in experimental studies. However, due to decreased oxygen supply and insufficient wash out of waste products in the inner layers of such preparations, electrophysiological functions could be compromised. Although the cascade of events triggered by cutting off perfusion is well known, it remains unclear as to which degree electrophysiological function in viable surface layers is affected by pathological processes occurring in adjacent tissue. Using a 3D numerical bidomain model, we aim to quantify the impact of superfusion-induced heterogeneities occurring in the depth of the tissue on impulse propagation in superficial layers. Simulations demonstrated that both the pattern of activation as well as the distribution of extracellular potentials close to the surface remain essentially unchanged. This was true also for the electrophysiological properties of cells in the surface layer, where most relevant depolarization parameters varied by less than 5.5 %. The main observed effect on the surface was related to action potential duration that shortened noticeably by 53 % as hypoxia deteriorated. Despite the known limitations of such experimental methods, we conclude that superfusion is adequate for studying impulse propagation and depolarization whereas repolarization studies should consider the influence of pathological processes taking place at the core of tissue sample