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Evasio Pasini Anna Cargnioni Fiorella Pastore Roberta Razzetti Stefano Bongrani Gian Luca Gitti Roberto Ferrari 《Pharmacological research》2004,49(1):1-5
Neurohormonal activation has been shown to be a major factor in congestive heart failure progression and mortality. The beneficial effects obtained in clinical trials with angiotensin converting enzyme (ACE) inhibitors, beta-blockers and aldosterone antagonists have confirmed this hypothesis. 5,6-Diisobutirroyloxy-2-methyl-aminotetraline hydrochloride (nolomirole) is a selective agonist of prejunctional D(2)-dopaminergic and alpha(2)-adrenergic receptors. The stimulation of these receptors inhibits catecholamine release from sympathetic nerve endings. To confirm that this mechanism can be useful in congestive heart failure, we studied the effects of nolomirole on monocrotaline-induced congestive heart failure. The ACE inhibitor trandolapril was used as reference compound. Rats were given single intraperitoneal injection of either saline (control group; n=20) or monocrotaline (50 mg kg(-1)). Three days later, the monocrotaline-treated animals were randomly allocated (n=50 per group) to oral treatment with distilled water (vehicle group), nolomirole (0.25 mg kg(-1)) twice a day, or trandolapril (0.3 mg kg(-1)) once a day up to sacrifice. On the fourth week after monocrotaline injection, animals with signs of congestive heart failure were sacrificed for evaluation of heart hypertrophy and neuroendocrine alterations. Atrial natriuretic peptide (ANP) and alderosterone were determined by radioimmunoassay in plasma. Tissue norepinephrine concentration was quantified by high-pressure liquid chromatography. Nolomirole and trandolapril significantly reduced (a) hypertrophy of right atria and ventricles, (b) plasma levels of ANP and presence of pleural/peritoneal effusions and (c) norepinephrine depletion of right ventricle. These findings confirmed that nolomirole, like trandolapril, is able to attenuate the heart failure signs in the monocrotaline-induced congestive heart failure model. 相似文献
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Metabolomics is one of the newer omics fields, and has enabled researchers to complement genomic and protein level analysis of disease with both semi-quantitative and quantitative metabolite levels, which are the chemical mediators that constitute a given phenotype. Over more than a decade, methodologies have advanced for both targeted (quantification of specific analytes) as well as untargeted metabolomics (biomarker discovery and global metabolite profiling). Untargeted metabolomics is especially useful when there is no a priori metabolic hypothesis. Liquid chromatography coupled to mass spectrometry (LC-MS) has been the preferred choice for untargeted metabolomics, given the versatility in metabolite coverage and sensitivity of these instruments. Resolving and profiling many hundreds to thousands of metabolites with varying chemical properties in a biological sample presents unique challenges, or pitfalls. In this review, we address the various obstacles and corrective measures available in four major aspects associated with an untargeted metabolomics experiment: (1) experimental design, (2) pre-analytical (sample collection and preparation), (3) analytical (chromatography and detection), and (4) post-analytical (data processing). 相似文献
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Sheffali Gulati 《Indian journal of pediatrics》2018,85(11):1000-1005
About one-third of childhood epilepsy ultimately becomes drug resistant epilepsy. Only about one-third of drug resistant epilepsy is amenable for epilepsy surgery. Epilepsy surgery and vagal nerve stimulation is still beyond the reach of huge proportion of children with pharmacoresistant epilepsy. Ketogenic diet (KD) has been in use for almost a century now all over the world for drug resistant epilepsy, although in between there was a decline in its popularity with advent of newer antiepileptic drugs like valproate, phenytoin and carbamazepine. Again from 1990s there was resurgence of interest in KD for pharmacoresistant epilepsy and in the last two decades several randomized controlled trials and systemic reviews have proved its efficacy beyond any suspicion. Ketogenic diet is a high fat low carbohydrate and low protein diet, which has been found to reduce epileptogenesis in body most probably by production of ketone bodies. Modified Atkin’s Diet (MAD) first introduced in 2003 and Low Glycemic Index Treatment (LGIT) first introduced in 2005 are another two dietary therapies, which are less restrictive, more palatable with fewer adverse effects and comparable efficacy. MAD is also a high fat, low carbohydrate diet, in which high sugar foods are discouraged and protein and fluids are unrestricted. In LGIT, only carbohydrates with Glycemic Index <50 are allowed and carbohydrate intake is restricted to 40–60 g per day. Medium Chain Triglyceride KD (MCT KD) is another alternative, in which there are more food choices as compared to classic KD, with comparable efficacy. 相似文献