247 resultados para J. A. F. Nicholls


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Adrenomedullin may provide a compensatory mechanism to attenuate left ventricular hypertrophy (LVH). Nitric oxide synthase inhibition, induced by chronic administration of N(omega)-nitro-L-arginine methyl ester (L-NAME) to rats, induces cardiac hypertrophy in some, but not all cases; there are few reports of direct assessment of cardiomyocyte parameters. The objective was to characterize hypertrophic parameters in left (LV) and right ventricular (RV) cardiomyocytes after administration of L-NAME to rats for 8 wk and to determine whether adrenomedullin and its receptor components were upregulated. After treatment with L-NAME (20 and 50 mg x kg(-1) x day(-1)), compared with nontreated animals, 1) systolic blood pressure increased (by 34.2 and 104.9 mmHg), 2) heart weight-to-body wt ratio increased 24.1% at the higher dose (P

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Adrenomedullin (AM) and intermedin (IMD; adrenomedulln-2) are vasodilator peptides related to calcitonin gene-related peptide (CGRP). The actions of these peptides are mediated by the calcitonin receptor-like receptor (CLR) in association with one of three receptor activity-modifying proteins. CGRP is selective for CLR/receptor activity modifying protein (RAMP)1, AM for CLR/RAMP2 and -3, and IMD acts at both CGRP and AM receptors. In a model of pressure overload induced by inhibition of nitric-oxide synthase, up-regulation of AM was observed previously in cardiomyocytes demonstrating a hypertrophic phenotype. The current objective was to examine the effects of blood pressure reduction on cardiomyocyte expression of AM and IMD and their receptor components. Nomega-nitro-L-arginine methyl ester (L-NAME) (35 mg/kg/day) was administered to rats for 8 weeks, with or without concurrent administration of hydralazine (50 mg/kg/day) and hydrochlorothiazide (7.5 mg/kg/day). In left ventricular cardiomyocytes from L-NAME-treated rats, increases (-fold) in mRNA expression were 1.6 (preproAM), 8.4 (preproIMD), 3.4 (CLR), 4.1 (RAMP1), 2.8 (RAMP2), and 4.4 (RAMP3). Hydralazine/hydrochlorothiazide normalized systolic blood pressure (BP) and abolished mRNA up-regulation of hypertrophic markers sk-alpha-actin and BNP and of preproAM, CLR, RAMP2, and RAMP3 but did not normalize cardiomyocyte width nor preproIMD or RAMP1 mRNA expression. The robust increase in IMD expression indicates an important role for this peptide in the cardiac pathology of this model but, unlike AM, IMD is not associated with pressure overload upon the myocardium. The concordance of IMD and RAMP1 up-regulation indicates a CGRP-type receptor action; considering also a lack of response to BP reduction, IMD may, like CGRP, have an anti-ischemic function.

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Background Natriuretic peptides are frequently measured in patients with chronic cardiac failure (CCF). We set out to compare the variability of atrial natriuretic peptide (C-ANP) and its precursor N-terminal pro-ANP (Nt-proANP) to decide which would be more suitable for routine use.

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Recent evidence suggests that HDL can directly inhibit LDL oxidation, a key early stage in atherogenesis. Patients with chronic renal failure are at increased cardiovascular risk, have reduced HDL levels and altered HDL composition. We have therefore investigated whether compositional changes in HDL lead to decreased HDL antioxidant capacity in these patients. In comparison to control subject HDL, patient HDL contained less total cholesterol, cholesterol esters, phospholipids and alpha-tocopherol. LDL, HDL and LDL + HDL were standardised for protein and oxidised in the presence of Cu2+. The rate of propagation during HDL oxidation was reduced in the patient group (3.28 +/- 0.65 x 10(-5) vs. 4.60 +/- 0.97 x 10(-5) abs. U/min, P

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Modern scientific world-view has undermined traditional myths, the functional survival of which seems to depend today in the West on a positivist justification. This would place them in the field of real History, through their study and revitalization by pseudoscientific disciplines such as the Atlantis and the ancient astronaut hypotheses. These have inspired new epic poems in (regular) verse that combine classic and/or biblical myths with a (pseudo)scientific modern world-view. For example, the critical rewriting of Noah’s myth by using the ancient astronaut hypothesis as a fictional device to produce a contemporary kind of plausibility allowed Abel Montagut to renew epic poetry, updating it also by adopting science fiction chronotopes in order to structure his fictional construction and to generate a high ethical sense for our time. Thus, his Poemo de Utnoa (1993) / La gesta d’Utnoa (1996), which has become a major classic of the literature in Esperanto thanks to its original version in this language, is a landmark of both science fiction and neo-biblical epics. This poem is written from a secular and purely literary perspective.

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Background: Bleomycin pulmonary toxicity (BPT) has been known since the early clinical trials of bleomycin in the 1960s. Postulated risk factors include cumulative bleomycin dose, reduced glomerular filtration rate (GFR), raised creatinine, older age and supplemental oxygen exposure.

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A diagnostic system for ICD-11 is proposed which commences with broad reorganization and simplification of the current categories and the use of clinically relevant specifiers. Such changes have implications for the positioning of diagnostic groups and lead to a range of possibilities for improving terminology and the juxtaposition of individual conditions. The development of ICD-11 provides the first opportunity in almost two decades to improve the validity and reliability of the international classification system. Widespread change in broad categories and criteria cannot be justified by research that has emerged since the last revision. It would also be disruptive to clinical practice and might devalue past research work. However, the case for reorganization of the categories is stronger and has recently been made by an eminent international group of researchers (Andrews et al., 2009). A simpler, interlinked diagnostic system is proposed here which is likely to have fewer categories than its predecessor. There are major advantages of such a system for clinical practice and research and it could also produce much needed simplification for primary care (Gask et al., 2008) and the developing world (Wig, 1990; Kohn et al., 2004).

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