Abstract-Day/night rhythms are recognized as important to normal cardiovascular physiology and timing of adverse cardiovascular events; however, their significance in disease has not been determined. We demonstrate that day/night rhythms play a critical role in compensatory remodeling of cardiovascular tissue, and disruption exacerbates disease pathophysiology. We use a murine model of pressure overload cardiac hypertrophy (transverse aortic constriction) in a rhythm-disruptive 20-hour versus 24-hour environment. Echocardiography reveals increased left ventricular end-systolic and -diastolic dimensions and reduced contractility in rhythm-disturbed transverse aortic constriction animals. Furthermore, cardiomyocytes and vascular smooth muscle cells exhibit reduced hypertrophy, despite increased pressure load. Microarray and real-time PCR demonstrate altered gene cycling in transverse aortic constriction myocardium and hypothalamic suprachiasmatic nucleus. With rhythm disturbance, there is a consequent altered cellular clock mechanism ( per2 and bmal), whereas key genes in hypertrophic pathways (ANF, BNP, ACE, and collagen) are downregulated paradoxical to the increased pressure. Phenotypic rescue, including reversal/attenuation of abnormal pathology and genes, only occurs when the external rhythm is allowed to correspond with the animals' innate 24-hour internal rhythm. Our study establishes the importance of diurnal rhythm as a vital determinant in heart disease. Disrupted rhythms contribute to progression of organ dysfunction; restoration of normal diurnal schedules appears to be important for effective treatment of disease. Key Words: cardiac hypertrophy Ⅲ renin-angiotensin-aldosterone system pathway Ⅲ remodeling Ⅲ gene expression microarrays Ⅲ circadian C ardiovascular disease is a major and increasing cause of death worldwide. Epidemiological studies suggest an important role for day/night rhythms in the cyclic variation of heart rate and blood pressure, 1,2 timing of endocrine hormone secretion, 3,4 temporal variations of cardiac vulnerability, 5 and susceptibility to adverse cardiovascular events (including myocardial infarction, 6,7 stroke, 8 angina, 9 ventricular arrhythmias, 10 dissection/rupture of aortic aneurysm, 11 and sudden cardiac death 12 ). Shift workers and patients with sleep disorders are at increased risk of adverse cardiovascular events and poorer prognosis. 13,14 However, there are no experimental data actually linking disturbed diurnal rhythms with cardiovascular pathophysiology and remodeling postinjury. Thus, relevance of diurnal rhythms is routinely ignored in clinical medicine; for example, diurnal rhythms are disturbed when multibedded rooms are used in intensive care units, and time of day is infrequently considered relevant for drug treatment or the efficacy of contemporary interventional procedures.Daily behavioral and physiological rhythms in mammals are driven by the circadian pacemaker in the suprachiasmatic nucleus (SCN) of the hypothalamus, 15,16 which orchestrates a hierarch...
These findings indicate that acute lipid and chronic HFD feeding in vivo, as well as acute palmitate and TNF-α exposure in vitro, induce markers of inflammation or ER stress in the hypothalamic appetite-stimulating NPY/AgRP neurons over time, which may contribute to a dramatic alteration in NPY/AgRP content or expression. Acute and chronic HFD feeding in vivo temporally regulates arcuate TNF-α expression with reactive astrocytosis, which suggests a time-dependent neurotrophic or neurotoxic role of lipids.
Herbivore-induced plants responses can affect the preference and performance of herbivores and their natural enemies. These responses may vary depending on the identity and number of herbivore species feeding on the plant so that when herbivores from different guilds feed on plants, the interactions between plants, herbivores, and natural enemies may be disrupted. Tomato plants were damaged either by the caterpillar Spodoptera exigua, or the aphid Macrosiphum euphorbiae, or damaged by both herbivores, or undamaged controls. We measured the preference and performance of S. exigua and its parasitoid Cotesia marginiventris, and activity of proteinase inhibitors (PI) as an indicator of induced resistance. Compared to undamaged plants, caterpillar damage reduced the number of eggs laid by S. exigua adults, reduced growth, consumption, and survival of larval S. exigua and C. marginiventris, and increased activity of PIs 43%; but did not increase attraction of C. marginiventris. While pupal mass of S. exigua was not affected, the pupal mass of C. marginiventris decreased on caterpillar-damaged plants compared to controls. In contrast, plants damaged by aphids were preferred for oviposition by S. exigua, and had increased larval consumption and survival, compared to controls. Aphid feeding did not affect the preference or performance of C. marginiventris, or PI activity, compared to controls. While oviposition was deterred on caterpillar-damaged plants, plants damaged by both herbivores received the same amount of oviposition as controls. The attraction of C. marginiventris to plants damaged by caterpillars and aphids was increased compared to controls. However, plants damaged by both herbivores had similar PI activity, larval growth and survival of S. exigua and C. marginiventris, as plants singly damaged by caterpillars. Overall, the preference component for both the herbivore and parasitoid was more strongly affected by damage due to multiple herbivores than the performance component.
A small but growing number of analysts of criminal activity have used social network analysis (SNA) to characterise criminal organisations and produce valuable insights into the operation of illicit markets. The successful conduct of SNA requires data that informs about links or relationships between pairs of individuals within the group. To date analyses have been undertaken with data extracted from offender databases, transcripts of physical or electronic surveillance, written summaries of police interrogations, and transcripts of court proceedings. These data can be expensive, time-consuming and complicated to access and analyse. This paper presents findings from a study which aimed to determine the feasibility and utility of conducting SNA using a novel source of data: judges' sentencing comments. Free of charge, publically accessible without the need for ethics clearance, available at the completion of sentencing and summary in nature, this data offers a more accessible and less expensive alternative to the usual forms of data used. The judges' sentencing comments were drawn from a series of Australian court cases involving members of a criminal group involved in the manufacture and distribution of methamphetamine during the 1990s. Feasibility is evaluated in terms of the ability to produce a network map and generate the types of quantitative measures produced in studies using alternate data sources. The utility of the findings is Crime Law Soc Change (2012) 57:151-176
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