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41.
42.
In this study, the acute toxicity of the organophosphorous pesticide (OP) dichlorvos and both in vitro and in vivo effects of dichlorvos on cholinesterase (ChE) activity of the European sea bass (Dicentrarchus labrax) were investigated. The characterisation of ChE and the “normal” range of activity in brain and muscle of non-exposed fish were determined in a first phase of the study. Acetylthiocholine was the substrate preferred of both brain and muscle ChE. Eserine sulphate and BW284C51 significantly inhibited the brain and muscle enzyme activity at low concentrations (μM range). Iso-OMPA had a significant effect in muscle, but not in brain tissue. These results suggest that acetylcholinesterase (AChE) is the predominant ChE form in brain tissue. In contrast, both acetylcholinesterase and butyrylcholinesterase seem to exist in muscle. Using acetylthiocholine as substrate, the “normal” range of fingerling head and muscle ChE were 58.05±2.11 and 118.03±8.67 U/mg protein, respectively. Corresponding values for juveniles were 43.32±4.42 and 19.44±2.44 U/mg protein for brain and muscle, respectively. Dichlorvos significantly inhibited the activity of ChE in the selected tissues, both in vitro and in vivo conditions. Differences in ChE sensitivity were found in relation to the age of the fish and the tissue analysed. The present study also showed that fingerlings of the European sea bass are relatively resistant to in vivo acute (96 h) dichlorvos exposure to concentrations between 0.125 and 1 mg/L, being able to tolerate high percentages of head ChE inhibition (37% and 76%) without lethal effects.  相似文献   
43.
Elevations in the plasma concentrations of natriuretic peptides correlate with increased severity of myxomatous mitral valve disease (MMVD) in dogs. This study correlates the severity of MMVD with the plasma concentrations of the biomarkers N-terminal fragment of the pro-brain-natriuretic peptide (NT-proBNP) and its second messenger, cyclic guanosine monophosphate (cGMP). Furthermore, the l-arginine:asymmetric dimethylarginine (ADMA) ratio was measured as an index of nitric oxide availability. The study included 75 dogs sub-divided into five groups based on severity of MMVD as assessed by clinical examination and echocardiography.Plasma NT-proBNP and cGMP concentrations increased with increasing valve dysfunction and were significantly elevated in dogs with heart failure. The cGMP:NT-proBNP ratio decreased significantly in dogs with heart failure, suggesting the development of natriuretic peptide resistance. Although the l-arginine:ADMA ratio decreased with increasingly severe MMVD, this was largely due to the older age of the dogs with heart failure.  相似文献   
44.

Background

Few previous studies have investigated the association between biomarkers and cardiac disease findings in dogs with naturally occurring myxomatous mitral valve disease (MMVD).

Aim

To investigate if histopathological changes at necropsy could be reflected by in vivo circulating concentrations of cTnI and aldosterone, and renin activity, in dogs with naturally occurring congestive heart failure because of MMVD.

Animals

Fifty privately owned dogs with MMVD and heart failure.

Methods

Longitudinal Study. Dogs were prospectively recruited and examined by clinical and echocardiographical examination twice yearly until time of death. Blood was stored for batched analysis of concentrations of cTnI and aldosterone, and renin activity. All dogs underwent a standardized necropsy protocol.

Results

cTnI were associated with echocardiographic left ventricular end‐diastolic dimension (P < .0001) and proximal isovolumetric surface area radius (< .004). Furthermore, in vivo cTnI concentrations reflected postmortem findings of global myocardial fibrosis (P < .001), fibrosis in the papillary muscles (P < .001), and degree of arterial luminal narrowing (< .001) Aldosterone or renin activity did not reflect any of the cardiac disease variables investigated.

Conclusion and clinical importance

Cardiac fibrosis and arteriosclerosis in dogs with MMVD are reflected by circulating cTnI concentration, but not by aldosterone concentration or renin activity. Cardiac troponin I could be a valuable biomarker for myocardial fibrosis in dogs with chronic cardiac diseases.  相似文献   
45.
Saliva contains a number of proteins that may be useful as biomarkers of health and disease and can be easily obtained from large numbers of animals in a non-invasive, stress-free way. The objective of this study was to explore the protein composition of porcine saliva from 10 specific pathogen free pigs using first one-dimensional SDS–PAGE and then two-dimensional electrophoresis and mass spectrometry. A reference proteome pattern for porcine saliva was established with the identification of 13 different, mainly saliva-specific, proteins. These reference data will facilitate the investigation of salivary proteins potentially altered in disease and could serve as novel diagnostic biomarkers.  相似文献   
46.
The objective of this study was to evaluate the serum proteinogram, identifying and quantifying the acute-phase proteins (APPs) of horses used in show jumping activity with obstacles of a meter in height. As it is an equestrian sport that involves high intensity and excessive impact, the possibility of injury is relevant. The serum of 10 horses was evaluated in a competition for beginners. The material was collected at rest (T0), immediately after exercise (T1), 30 minutes after the effort (T2), 1 hour after the effort (T3), and 24 hours after the effort. Acute-phase proteins were separated by polyacrylamide gel electrophoresis and their concentrations determined by computerized densitometry. Protein identification was performed using mass spectrometry. The data were evaluated using analysis of variance for repeated measures, considering the level of significance of P < .05. Eight APPs were identified: α2-macroglobulin (α2-macro), ceruloplasmin (Cp), transferrin (Trf), albumin (Alb), α1-antitrypsin (α1-atp), haptoglobin (Hp), acid glycoprotein (AGP), and apolipoprotein A1 (Apo A1). There was a difference in Cp, AGP, and Apo A1 between moments. As the other proteins were not influenced by exercise, they were established as a valuable resource in the monitoring of inflammatory processes and an important complementary element in controlling the impact of training on the animals, thus guaranteeing their welfare.  相似文献   
47.
蛋白质组学作为后基因组学时代研究的重要课题,已经广泛深入到了生命科学的各个领域,应用蛋白质学技术寻到敏感性、特异性的癌症标志物,为更好地进行癌症诊断研究提供了良好平台。本文对蛋白质组学的现状和相关研究技术进行了介绍,并概括了蛋白质组学在癌症方面的研究进展。  相似文献   
48.

Background

Cardiac biomarkers provide objective data that augments clinical assessment of heart disease (HD).

Hypothesis/Objectives

Determine the utility of plasma N‐terminal pro‐brain natriuretic peptide concentration [NT‐proBNP] measured by a 2nd generation canine ELISA assay to discriminate cardiac from noncardiac respiratory distress and evaluate HD severity.

Animals

Client‐owned dogs (n = 291).

Methods

Multicenter, cross‐sectional, prospective investigation. Medical history, physical examination, echocardiography, and thoracic radiography classified 113 asymptomatic dogs (group 1, n = 39 without HD; group 2, n = 74 with HD), and 178 with respiratory distress (group 3, n = 104 respiratory disease, either with or without concurrent HD; group 4, n = 74 with congestive heart failure [CHF]). HD severity was graded using International Small Animal Cardiac Health Council (ISACHC) and ACVIM Consensus (ACVIMHD) schemes without knowledge of [NT‐proBNP] results. Receiver‐operating characteristic curve analysis assessed the capacity of [NT‐proBNP] to discriminate between dogs with cardiac and noncardiac respiratory distress. Multivariate general linear models containing key clinical variables tested associations between [NT‐proBNP] and HD severity.

Results

Plasma [NT‐proBNP] (median; IQR) was higher in CHF dogs (5,110; 2,769–8,466 pmol/L) compared to those with noncardiac respiratory distress (1,287; 672–2,704 pmol/L; < .0001). A cut‐off >2,447 pmol/L discriminated CHF from noncardiac respiratory distress (81.1% sensitivity; 73.1% specificity; area under curve, 0.84). A multivariate model comprising left atrial to aortic ratio, heart rate, left ventricular diameter, end‐systole, and ACVIMHD scheme most accurately associated average plasma [NT‐proBNP] with HD severity.

Conclusions and Clinical Importance

Plasma [NT‐proBNP] was useful for discriminating CHF from noncardiac respiratory distress. Average plasma [NT‐BNP] increased significantly as a function of HD severity using the ACVIMHD classification scheme.  相似文献   
49.
The potential use of acetylcholinesterase (AChE) and metallothionein (MT) responses as biomarker of organophosphorous (OPs) and trace metal were assessed in fish Seriola dumerilli exposed to 0, 4, 6 mg/kg of malathion for 2, 7 and 13 days, and to 0, 50, 100, 250 μg/kg of Cd for 2 days. Brain AChE was significantly inhibited after 2 and 7 days of malathion exposure, in a dose–response manner, but no inhibition was observed after 13 days of exposure. When exposed to Cd for 2 days, S. dumerelli presented an increase in AChE activity at a concentration of 50 μg/kg, but a strong and dose-dependent AChE inhibition at 100 and 250 μg/kg. Cd treatment also caused a rapid increase in MTs concentration in liver, even at the lower concentration. Our experiments indicate that the measurement of hepatic MT concentration and brain AChE activity in S. dumerilli would be useful biomarkers of OP and Cd exposure and/or effects.  相似文献   
50.
Depression is a kind of common mental disorder, which seriously endangers people's health and life. Its pathogenesis is complex and still not completely clear. Metabolomics is an emerging method of systematic biology research that is systematic and holistic. These characteristics are consistent with the complexity of depression. Therefore, more and more studies have been carried out on depression based on metabolomics, which provide us with a wealth of data and information. This paper reviewed researches of depression based on metabolomics, and summarized biomarkers and metabolic pathways related to depression patients and depression model animals, in order to provide more information and direction for the study of depression.  相似文献   
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