996 resultados para Lea, Langdon "Biff"


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The current study investigated the relationship between career-related mentoring, psychosocial mentoring, business success, and self-esteem in participants of a program that was designed to assist in the establishment of a new business. Seventy-seven protégés and their matched mentors were included in the study. A comparison of mentor and protégé perceptions revealed that mentors considered themselves to provide higher levels of psychosocial support than did the protégés. Protégé perceptions of business success were predicted by the frequency of mentor contact and the level of career-related support provided by their mentor.

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The isolated Langendorff-mode perfused heart has become a valuable experimental model, used extensively to examine cardiac function, pathophysiology and pharmacology. For the clinical cardiologist an ECG is often a simple practicality, however in experimental circumstances, particularly with ex vivo murine hearts it is not always possible to obtain an ECG due to experimental recording constraints. However, the mechanical record of ventricular contractile function can be highly informative in relation to electrical state. It is difficult though to achieve consistency in these evaluations of arrhythmia as a validated common reference framework is lacking. In 1988, a group of investigators developed the ‘Lambeth Conventions’—a standardised reference for the definition and classification of arrhythmias in animal experimental models of ischaemia, infarction and reperfusion in vivo. Now, two decades later it is timely to revisit the Lambeth Conventions, and to update the guidelines in the context of the marked increase in murine heart study in experimental cardiac pathophysiology. Here we describe an adjunct to the Lambeth Conventions for the reporting of ventricular arrhythmias post-ischaemia in ex vivo mouse hearts when ECG recordings are not employed. Of seven discrete and identifiable patterns of mechanical dysrhythmia observed in reperfusion, five could be classified using conventional ECG terminology: ventricular premature beat, bigeminy, trigeminy, ventricular tachycardia and ventricular fibrillation. Two additional rhythm variations detected from the pressure record are described (potentiated contraction and alternans).

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Important sex differences in cardiovascular disease outcomes exist, including conditions of hypertrophic cardiomyopathy and cardiac ischemia. Studies of sex differences in the extent to which load-independent (primary) hypertrophy modulates the response to ischemia-reperfusion (I/R) damage have not been characterized. We have previously described a model of primary genetic cardiac hypertrophy, the hypertrophic heart rat (HHR). In this study the sex differences in HHR cardiac function and responses to I/R [compared to control normal heart rat (NHR)] were investigated ex vivo. The ventricular weight index was markedly increased in HHR female (7.82 ± 0.49 vs. 4.80 ± 0.10 mg/g; P < 0.05) and male (5.76 ± 0.22 vs. 4.62 ± 0.07 mg/g; P < 0.05) hearts. Female hearts of both strains exhibited a reduced basal contractility compared with strain-matched males [maximum first derivative of pressure (dP/dtmax): NHR, 4,036 ± 171 vs. 4,258 ± 152 mmHg/s; and HHR, 3,974 ± 160 vs. 4,540 ± 259 mmHg/s; P < 0.05]. HHR hearts were more susceptible to I/R (I = 25 min, and R = 30 min) injury than NHR hearts (decreased functional recovery, and increased lactate dehydrogenase efflux). Female NHR hearts exhibited a significantly greater recovery (dP/dtmax) post-I/R relative to male NHR (95.0 ± 12.2% vs. 60.5 ± 9.4%), a resistance to postischemic dysfunction not evident in female HHR (29.0 ± 5.6% vs. 25.9 ± 6.3%). Ventricular fibrillation was suppressed, and expression levels of Akt and ERK1/2 were selectively elevated in female NHR hearts. Thus the occurrence of load-independent primary cardiac hypertrophy undermines the intrinsic resistance of female hearts to I/R insult, with the observed abrogation of endogenous cardioprotective signaling pathways consistent with a potential mechanistic role in this loss of protection.

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Introduction
Angiotensin II (Ang II) is known to induce cardiac growth and modulate myocardial contractility. It has been reported that elevated levels of endogenous Ang II contribute to the development of cardiac hypertrophy in hypertensives. However, the long-term functional effects of cardiac exposure to Ang II in normotensives is unclear.

A recently developed transgenic mouse (TG1306/1R), in which cardiac-specific overproduction of Ang II produces primary hypertrophy, provides a new experimental model for investigation of this phenotype. The aim of the present study was to use this model to investigate whether there is a functional deficit in primary hypertrophy that may predispose to cardiac failure and sudden death. We hypothesised that primary cardiac hypertrophy is associated with mechanical dysfunction in the basal state.

Methods
Normotensive heterozygous TG1306/1R mice harbouring multiple copies of a cardiac-specific rat angiotensinogen gene were studied at age 30—40 weeks and compared with age-matched wild-type littermates. Left ventricular function was measured ex vivo in bicarbonate buffer-perfused, Langendorffmounted hearts ( at a perfusion pressure of 80 mmHg, 37°C) using a fluid-filled PVC balloon interfaced to a pressure transducer and digital data acquisition system.

Results
There was no difference in the mean (±SEM) intrinsic heart rate of TG1306/1R and wild-type control mice (357.4±11.8 vs. 367.5±20.9 bpm, n=9 & 7). Under standardised end-diastolic pressure conditions, TG1306/1R hearts exhibited a significant reduction in peak developed pressure (132.2±9.4 vs. 161.5±3.1 mmHg, n=9 & 7, p<0.05) and maximum rate of pressure development (3566.7±323.7 vs. 4486.3±109.4 mmHg, n=9 & 7, p<0.05). TG1306/1R mice show a significant correlation between incidence of arrhythmia and increasing heart size (Spearman's correlation coefficient 0.61).

Conclusion
These data demonstrate that chronic in vivo exposure to elevated levels of intra-cardiac Ang II is associated with significant contractile abnormalities evident in the ex vivo intact heart. Our findings suggest that endogenous overproduction of cardiac Ang II, independent of changes in blood pressure, is sufficient to induce ventricular remodelling that culminates in impaired cardiac function which may precede failure.

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The Hypertrophic Heart Rat (HHR) displays spontaneous cardiomyocyte hypertrophy in association with an apparent reduction in myocyte number in adulthood. This suggests the possibility of reduced hyperplasia or increased apoptosis during early cardiac development. The angiotensin AT1 and AT2 receptor subtypes have been implicated in both cellular growth and apoptosis, but the precise mechanisms are unclear. The aim of this study was to determine the relationship between cardiac AngII receptor expression levels and neonatal cardiomyocyte growth and apoptotic responses in the HHR compared with the Normal Heart Rat (NHR) control strain. Cardiac tissues were freshly harvested from male HHR and NHR at several developmental stages (p2 and 4, 6, 8, 12wks). HHR cardiac weight indices were considerably smaller than NHR at day 2 (4.330.19 vs 5.010.08 mg/g), but ‘caught-up’ to NHR by 4 weeks (5.100.15 vs 5.160.11 mg/g). By 12 weeks, HHR hearts were 27% larger than NHR. Tissue AT1A and AT2 mRNA expression levels were quantified by real-time RT-PCR. Relative to NHR, HHR neonatal hearts exhibited a 4.6-fold higher AT2/AT1 mRNA expression ratio. Cultured neonatal cardiomyocytes were infected with AT1A and/or AT2 receptor-expressing adenoviruses to achieve a physiological level of receptor expression (150 fmol receptor protein/mg total cell protein). In addition, to emulate receptor expression in neonatal HHR hearts, cells were co-infected with AT1A and AT2 receptors at a 4:1 ratio. Apoptosis incidence was studied by morphological analysis after 72 hours exposure to 0.1 M AngII. When infected with the AT1A receptor alone, a higher proportion of HHR myocytes appeared apoptotic than NHR (22.7 4.1% vs 1.1 0.6%, P 0.001). This implies that intrinsic differences predispose HHR cells to accentuated AT1-mediated apoptosis. Interestingly, the bax-1/bcl-2 mRNA expression ratio was significantly higher (50%) in HHR neonatal hearts. When cells were co-infected with AT1A and AT2 receptors, evidence of apoptosis in HHR cells virtually disappeared (0.4 0.1%). These findings suggest a novel capacity of AT2 receptors to counteract accentuated AT1A receptor-induced apoptosis in the HHR in early cardiac growth.

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Bacteriophage NCIMB-10645 of Serratia marcescens (NCIMB-10644) was assessed as a tracer of aquatic contamination with the intention of using it at the Black Rock ocean outfall in South Eastern Australia. Growth conditions and a liquid culture growth curve were assessed. The bacteriophage was subjected to survival trials and a method of concentrating NCIMB-10645 developed. NCIMB-10645 was assessed as a tracer at Deakin University then released from the Black Rock Sewage Treatment Plant. Contamination movement away from the treatment plant was found to be predominantly affected by Easterly wind conditions.

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Investigates alternative solutions to promoting psychological health during unemployment. Unemployed people who engage in meaningful leisure activity, who had a pro-active approach to coping, and utilised more social support networks, demonstrated better psychological adjustment. Suggests that such activities may contribute to re-employment.

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Background
There is an urgent need for more carefully developed public health measures in order to curb the obesity epidemic among youth. The overall aim of the "EuropeaN Energy balance Research to prevent excessive weight Gain among Youth" (ENERGY)-project is the development and formative evaluation of a theory-informed and evidence-based multi-component school-based and family-involved intervention program ready to be implemented and evaluated for effectiveness across Europe. This program aims at promoting the adoption or continuation of health behaviors that contribute to a healthy energy balance among school-aged children. Earlier studies have indicated that school and family environments are key determinants of energy-balance behaviors in schoolchildren. Schools are an important setting for health promotion in this age group, but school-based interventions mostly fail to target and involve the family environment.

Methods

Led by a multidisciplinary team of researchers from eleven European countries and supported by a team of Australian experts, the ENERGY-project is informed by the Environmental Research Framework for Weight gain Prevention, and comprises a comprehensive epidemiological analysis including 1) systematic reviews of the literature, 2) secondary analyses of existing data, 3) focus group research, and 4) a cross European school-based survey.

Results and discussion
The theoretical framework and the epidemiological analysis will subsequently inform stepwise intervention development targeting the most relevant energy balance-related behaviors and their personal, family-environmental and school-environmental determinants applying the Intervention Mapping protocol. The intervention scheme will undergo formative and pilot evaluation in five countries. The results of ENERGY will be disseminated among key stakeholders including researchers, policy makers and the general population.

Conclusions
The ENERGY-project is an international, multidisciplinary effort to develop and test an evidence-based and theory-informed intervention program for obesity prevention among school-aged children.

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Purpose – Aims to investigate the relationships between consumers' food concerns and their personal values and demographic characteristics.

Design/methodology/approach – A questionnaire was administered in a cross sectional random population survey conducted among a sample of 1,000 adults in South Australia. The questionnaire elicited information about respondents' concerns about 20 food and health issues, the perceived importance of 23 values items derived from the Schwartz values inventory, and their demographic characteristics.

Findings –
Principal components analyses derived four food concerns factors and six personal values factors. Respondents' safety concerns scores were positively associated with devout-tradition, order-discipline, and moderate-independent values. Their disease concerns score was positively linked to beauty-nature, devout-tradition, and order-discipline. Multiple regression and chi-square automatic interaction detection (CHAID) analyses showed that individual values items were strong predictors of consumers; specific concerns such as food and heart disease, and, genetic modification of foods.

Research limitations/implications – The research was based on a cross sectional study. More refined indices of food concerns and personal values should be used in replications of this preliminary study.

Practical implications – The findings support the use of psychographic market segmentation approaches in communication programs about food and health issues.

Originality/value – The findings suggest that personal values, may be stronger predictors of consumers' concerns about food and health issues than demographics. They also show that measurement level of values and concerns influence the observed strength of their relationships.

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The aim of this study was to examine Australians’ food-related environmental beliefs and behaviours. Questionnaires were posted to 500 randomly selected adults, with 223 questionnaires completed (58% response rate). Decreased use of packaging by food manufacturers was viewed as being the most important item to help the environment, while lower meat consumption was seen as least likely to help. Composting food scraps and purchase or consumption of locally produced foods were the most commonly performed food-related environmental behaviours, while use of organic products was the least commonly performed. Moderate consistency (rs=0.54) was found between reported beliefs and behaviours. Older people were more likely to perform certain food-related environmental behaviours, such as composting. Awareness of the impact on the environment of meat production, organic compared to conventional farming, and food packaging was low even among those who were found to already believe that food-related actions are important to help the environment, suggesting widespread consciousness raising is needed.

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Purpose – The aim of this exploratory study was to examine and compare a range of business values held by farmers and food processors.

Design/methodology/approach – Questionnaires with a section on business values were posted to 200 farmers and 200 food processing businesses in Victoria, Australia, with response rates of 44 per cent (n=69) and 31 per cent (n=48), respectively, achieved.

Findings – The most important of the 28 value items for farmers were high quality produce, honesty, and caring for employees. For processors, the most important values were quality products, customer value, and caring for employees. Between group differences reached statistical significance for one-third of the items. In particular, processor businesses valued innovation and convenience products more highly and had a stronger process orientation than did farming businesses. Environmental sustainability, caring for the community, and providing healthy products were more integral to farming than processing businesses.

Research limitations/implications –
The main limitation was the small sample sizes, although it is likely that response bias was not high. Future research could survey a larger sample of food industry representatives and examine the values held by other food industry sectors.

Practical implications –
This information could increase the effectiveness of communications with industry groups on a range of issues and in the formulation of appropriate health and environmental policies.

Originality/value – To the authors' knowledge, this is the first study to compare the values of farmers and food processors. This information is particularly important for those in the food industry and health and environmental policy makers.

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