973 resultados para Anderson, Erick
Resumo:
The article by Kretzschmar et al 1 in this issue of Menopause details a study investigating the effect of a mild-intensity aerobic exercise training program on markers of mortality risk in both pre- and post-menopausal African American women. The findings of this study showed that aerobic exercise training was successful in improving some markers of cardiovascular disease (CVD) and mortality in post-menopausal women. The premise of this study, however, does suggest that increased exercise intensity may be required in post-menopausal women as opposed to pre-menopausal women to achieve the same decreased changes in CVD markers. The outcome of the study is thus of interest to the readers of Menopause and to all those who provide health care to postmenopausal women, as it suggests that higher levels of exercise intensity or perhaps additional interventions may need to be considered in this population to further decrease mortality risk. The study therefore, has greater implications than simply the suggestion of tailoring exercise interventions generally; rather, the publication highlights the importance of prescribing exercise as medicine in a tailored fashion for women depending on their menopausal status.
Resumo:
Background Poor mental health is a significant cause of morbidity and mortality, yet debate continues about factors most likely to predict poor mental health outcomes. Objective This cohort study examines the influence of modifiable lifestyle factors, menopausal symptoms, and physical health on the mental health of midlife and older Australian women. Methods: Random sampling was used to recruit women aged 40-55, from rural and urban areas of Queensland, Australia. Overall, 340 women completed mailed surveys on socio-demographic characteristics, midlife symptoms (Greene Climacteric Scale©), modifiable lifestyle factors, and mental health (SF-12©) in 2001, 2004 and 2011. Hierarchical repeated-measure models were used to explore the correlates of poor mental health over time. Results The mean age [SD] at baseline was 55 [2.7] years, most were married (73%, n=248) and 18% were pre-menopausal. The model suggested that variance in mental health widened and showed a non-linear increase with age. Decrements in mental health were associated with an increase in midlife symptoms (Greene psychological scale, P <0.01; Greene somatic scale, P <0.05), time (P <0.01), poor physical health (P <0.01) and individual variance (P <0.01). Socio-demographics and lifestyle factors had little influence on mental health over time. Conclusion Findings suggest that while women’s mental health may decline during midlife, the effect is temporary; in older women, physical health and individual factors seem to be increasingly significant. This research highlights the importance of active health promotion as a means of enhancing both physical and mental health in midlife women.
Resumo:
Bond characteristics of masonry are partly affected by the type of mortar used, the techniques of dispersion of mortar and the surface texture of the concrete blocks. Additionally it is understood from the studies on conventional masonry, the bond characteristics are influenced by masonry age and curing methods as well as dryness/dampness at the time of testing. However, all these effects on bond for thin bed masonry containing polymer cement mortar are not well researched. Therefore, the effect of ageing and curing method on bond strength of masonry made with polymer cement mortar was experimentally investigated as part of an ongoing bond strength research program on thin bed concrete masonry at Queensland University of technology. This paper presents the experimental investigation of the flexural and shears bond characteristics of thin bed concrete masonry of varying age/ curing methods. Since, the polymer cement mortar is commonly used in thin bed masonry; bond development through two different curing conditions (dry/wet) was investigated in this research work. The results exhibit that the bond strength increases with the age under the wet and dry curing conditions; dry curing produce stronger bond and is considered as an advantage towards making this form of thin bed masonry better sustainable.
Resumo:
There is emerging evidence for the important role of metacognitions in the presentation of eating disorders (EDs); however it is unclear to what extent these metacognitions are transdiagnostic. This study used a mixed methods convergent design to explore this question by triangulating both qualitative and quantitative data from 27 women, aged 18–55 years, with diagnoses of anorexia nervosa, bulimia nervosa, or eating disorders not otherwise specified. The results indicated that metacognitions in EDs may be transdiagnostic and may in part explain temporal migration between diagnoses and the degree of comorbidity associated with EDs.
Resumo:
The book is mostly designed for students of echocardiography, teachers of echocardiography and cardiac sonographers working in routine clinical practice, but will also be very useful to echocardiologists and cardiac registrars. The goal of the text is to provide a comprehensive review of transthoracic echocardiography in the assessment of various cardiac pathologies. Refresher notes on cardiac anatomy and the relevant cardiac physiology and pathophysiology are included to expand the cardiac sonographer’s knowledge in this area and further their understanding of various diseases, disease processes and associated findings.
Resumo:
It is well established that calcitonin is a potent inhibitor of bone resorption; however, a physiological role for calcitonin acting through its cognate receptor, the calcitonin receptor (CTR), has not been identified. Data from previous genetically modified animal models have recognized a possible role for calcitonin and the CTR in controlling bone formation; however, interpretation of these data are complicated, in part because of their mixed genetic background. Therefore, to elucidate the physiological role of the CTR in calcium and bone metabolism, we generated a viable global CTR knockout (KO) mouse model using the Cre/loxP system, in which the CTR is globally deleted by >94% but <100%. Global CTRKOs displayed normal serum ultrafiltrable calcium levels and a mild increase in bone formation in males, showing that the CTR plays a modest physiological role in the regulation of bone and calcium homeostasis in the basal state in mice. Furthermore, the peak in serum total calcium after calcitriol [1,25(OH)2D3]-induced hypercalcemia was substantially greater in global CTRKOs compared with controls. These data provide strong evidence for a biological role of the CTR in regulating calcium homeostasis in states of calcium stress.
Resumo:
Gene expression profiling using microarrays and xenograft transplants of human cancer cell lines are both popular tools to investigate human cancer. However, the undefined degree of cross hybridization between the mouse and human genomes hinders the use of microarrays to characterize gene expression of both the host and the cancer cell within the xenograft. Since an increasingly recognized aspect of cancer is the host response (or cancer-stroma interaction), we describe here a bioinformatic manipulation of the Affymetrix profiling that allows interrogation of the gene expression of both the mouse host and the human tumour. Evidence of microenvironmental regulation of epithelial mesenchymal transition of the tumour component in vivo is resolved against a background of mesenchymal gene expression. This tool could allow deeper insight to the mechanism of action of anti-cancer drugs, as typically novel drug efficacy is being tested in xenograft systems.
Accelerometer data reduction : a comparison of four reduction algorithms on select outcome variables
Resumo:
Purpose Accelerometers are recognized as a valid and objective tool to assess free-living physical activity. Despite the widespread use of accelerometers, there is no standardized way to process and summarize data from them, which limits our ability to compare results across studies. This paper a) reviews decision rules researchers have used in the past, b) compares the impact of using different decision rules on a common data set, and c) identifies issues to consider for accelerometer data reduction. Methods The methods sections of studies published in 2003 and 2004 were reviewed to determine what decision rules previous researchers have used to identify wearing period, minimal wear requirement for a valid day, spurious data, number of days used to calculate the outcome variables, and extract bouts of moderate to vigorous physical activity (MVPA). For this study, four data reduction algorithms that employ different decision rules were used to analyze the same data set. Results The review showed that among studies that reported their decision rules, much variability was observed. Overall, the analyses suggested that using different algorithms impacted several important outcome variables. The most stringent algorithm yielded significantly lower wearing time, the lowest activity counts per minute and counts per day, and fewer minutes of MVPA per day. An exploratory sensitivity analysis revealed that the most stringent inclusion criterion had an impact on sample size and wearing time, which in turn affected many outcome variables. Conclusions These findings suggest that the decision rules employed to process accelerometer data have a significant impact on important outcome variables. Until guidelines are developed, it will remain difficult to compare findings across studies
Common origins of MDA-MB-435 cells from various sources with those shown to have melanoma properties
Resumo:
Recently, the tissue origin of MDA-MB-435 cell line has been the subject of considerable debate. In this study, we set out to determine whether MDA-MB-435-DTP cells shown to express melanoma-specific genes were identical to various other MDA-MB-435 cell stocks worldwide. CGH-microarray, genetic polymorphism genotyping, microsatellite fingerprint analysis and/or chromosomal number confirmed that the MDA-MB-435 cells maintained at the Lombardi Comprehensive Cancer Center (MDA-MB-435-LCC) are almost identical to the MDA-MB-435-DTP cells, and showed a very similar profile to those obtained from the same original source (MD Anderson Cancer Center) but maintained independently (MDA-MB-435-PMCC). Gene expression profile analy-sis confirmed common expression of genes among different MDA-MB-435-LCC cell stocks, and identified some unique gene products in MDA-MB-435-PMCC cells. RT-PCR analysis confirmed the expression of the melanoma marker tyrosinase across multiple MDA-MB-435 cell stocks. Collectively, our results show that the MDA-MB-435 cells used widely have identical origins to those that exhibit a melanoma-like gene expression signature, but exhibit a small degree of genotypic and phenotypic drift.
Resumo:
We have investigated the gelatinase profiles and invasiveness of clonal tumour sublines derived from a spontaneously arising mammary tumour in a Balb/cfC3H mouse. The 67NR, 66c14 and 4T1.2 sublines have low, intermediate and high metastatic potential respectively. In Boyden chamber studies, Matrigel invasion was seen to be progressively higher in the more metastatic lines 4T1.2>66c14>67NR, consistent with MMP-2 activation potential, MMP-9 secretion, and migration over either type I or IV collagen, which were low in both 67NR and 66c14 cells compared to 4T1.2 cells. These attributes are consistent with those seen in human breast cancer cell lines which appear to have undergone an epithelial-mesenchymal transition (EMT) as indicated by vimentin expression. We were, however, surprised to find vimentin expression, MT1-MMP expression and stellate Matrigel outgrowth in the non-invasive, non-metastatic 67NR cells, indicating that they had undergone an EMT despite not being invasive. We conclude that the EMT is manifested to differing degrees in these three clonal cell lines, and that the 67NR cells have either undergone a partial EMT or have since lost certain important attributes of the EMT-derived phenotype. This model should prove useful in further characterizing the regulation of MT1-MMP mediated MMP-2 activation and delineating the EMT in breast cancer progression.
Resumo:
Recently, two landmark reports on antiangiogenic therapy were published: Paez-Ribes and colleagues and Ebos and colleagues . The Board of the Metastasis Research Society (MRS) congratulates the authors for their informative articles that help to explain the puzzle of why antiangiogenic agents have had a relatively minor or no significant impact on patient survival. Using four model systems and several different strategies, these researchers showed that inhibition of angiogenesis reduced primary tumor growth and microvessel density in keeping with many earlier reports, but strikingly, accelerated invasion and metastasis.
Resumo:
Human alterations to nutrient cycles1, 2 and herbivore communities3, 4, 5, 6, 7 are affecting global biodiversity dramatically2. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems8, 9. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light.
Resumo:
Multiple lines of evidence have provided compelling evidence for the existence of a tumor suppressor gene (TSG) on chromosome 7q31.1. ST7 may be the target of this genetic instability but its designation as a TSG is controversial. In this study, we show that, functionally, ST7 behaves as a tumor suppressor in human cancer. ST7 suppressed growth of PC-3 prostate cancer cells inoculated subcutaneously into severe combined immunodeficient mice, and increased the latency of tumor detection from 13 days in control tumors to 23 days. Re-expression of ST7 was also associated with suppression of colony formation under anchorage-independent conditions in MDA-MB-231 breast cancer cells and ST7 mRNA expression was downregulated in 44% of primary breast cancers. Expression profiling of PC-3 cells revealed that ST7 predominantly induces changes in genes involved in re-modeling the extracellular matrix such as SPARC, IGFBP5 and several matrix metalloproteinases. These data indicate that ST7 may mediate tumor suppression through modification of the tumor microenvironment.
Resumo:
Background Participation in regular physical activity is among the most promising and cost effective strategies to reduce physical and cognitive decline and premature death. However, confusion remains about the amount, frequency, and duration of physical activity that is likely to provide maximum benefit as well as the way in which interventions should be delivered. Aims This paper aimed to review research on the impact of leisure-time and general physical activity levels on physical and cognitive decline in postmenopausal women. In a systematic review of the literature, empirical literature from 2009-2013 is reviewed to explore the potential impact of either commencing or sustaining physical activity on older women’s health. Results All studies found that physical activity was associated with lower rates of cognitive and physical decline and a significant reduction in all-cause mortality. In this review we found that exercise interventions (or lifestyle activities) that improved cardiorespiratory exercise capacity showed the most positive impact on physical health. Conclusions Findings suggest that programs should facilitate and support women to participate in regular exercise by embedding physical activity programs in public health initiatives, by developing home-based exercise programs that require few resources and by creating interventions that can incorporate physical activity within a healthy lifestyle. The review also suggests that clinicians should consider prescribing exercise in a tailored manner for older women to ensure that it is of a high enough intensity to obtain the positive sustained effects of exercise.