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1.
Food Chem ; 302: 125373, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442706

RESUMO

The aim of this work was to investigate and compare the phenolic profile of 15 wild growing blackthorn (Prunus spinosa L.) genotypes from the slopes of Fruska Gora mountain in north Serbia. Their effect in inhibiting i) α-amylase and α-glucosidase activities and ii) colorectal cancer cell line (HT29) growth was also studied. Blackthorn fruit extracts exhibited high phenolic content being enrich in anthocyanins. Principal component analysis was used to correlate the bioactive response with phenolic composition. It was found that derivatives quercetin and anthocyanin peonidin are the major contributors of the inhibition of carbohydrates hydrolyzing enzymes as well as with the antiproliferative effect of blackthorn. Among all samples, the genotype from Beska locality showed the higher capacity in inhibiting alpha-amylase, alpha-glucosidase and HT29 cell growth. Because of high anthocyanin content and higher bioactive response, these genotypes could be recommended for the further cultivation and investigation.


Assuntos
Polifenóis/análise , Prunus/química , Prunus/genética , Antocianinas/análise , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/análise , Ácido Clorogênico/análogos & derivados , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/estatística & dados numéricos , Frutas/química , Genótipo , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Células HT29 , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Análise de Componente Principal , Quercetina/análise , Ácido Quínico/análogos & derivados , Ácido Quínico/análise , Sérvia , alfa-Amilases/antagonistas & inibidores
2.
Clin Breast Cancer ; 19(6): e731-e740, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31522958

RESUMO

Atrophic vaginitis is a relatively common adverse effect of aromatase inhibitors used as an adjunctive treatment for breast cancer. Vaginal estrogen therapy is a treatment option, but the safety of its use in estrogen receptor-positive breast cancer remains understudied. The aim of our study was to determine the safety of local hormonal treatment of vulvovaginal atrophy in women treated with aromatase inhibitors. Our meta-analysis was based on a systematic search of the literature and selection of high-quality evidence. The safety of local hormonal therapy of vaginal atrophy in women on aromatase inhibitors were summarized using calculators built by the authors; heterogeneity was assessed by the Cochrane Q test and I2 values. Several types of bias were assessed; publication bias was calculated by a funnel plot and the Egger regression. Eleven studies fulfilled the inclusion criteria for our study. After 8 weeks of local hormonal treatment, there was no change in the serum levels of luteinizing hormone and estradiol, whereas sex hormone binding globulins were low, and follicle stimulating hormone was almost doubled compared with the baseline. Adverse effect rates of vaginal discharge, facial hair growth, urinary tract or yeast infection, and vaginal or vulvar itching and/or irritation did not show significant changes in the sensitivity analysis, with exception of a single trial. Current evidence suggests that vaginal estrogen administration in postmenopausal women with a history of breast cancer is not associated with systemic absorption of sex hormones and may provide indirect evidence for the safety of their use.


Assuntos
Inibidores da Aromatase/efeitos adversos , Atrofia/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Terapia de Reposição Hormonal/métodos , Receptores de Estrogênio/metabolismo , Doenças Vaginais/tratamento farmacológico , Doenças da Vulva/tratamento farmacológico , Atrofia/induzido quimicamente , Atrofia/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Prognóstico , Doenças Vaginais/induzido quimicamente , Doenças Vaginais/patologia , Doenças da Vulva/induzido quimicamente , Doenças da Vulva/patologia
3.
J Plant Res ; 130(3): 559-570, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28243831

RESUMO

In this study, poplar tissue culture (hybrid black poplar, M1 genotype) was subjected to water stress influenced by polyethyleneglycol 6000 (100 and 200 mOsm PEG 6000). The aim of the research was to investigate the biochemical response of poplar tissue culture on water deficit regime. Antioxidant status was analyzed including antioxidant enzymes, superoxide-dismutase (SOD), catalase (CAT), guiacol-peroxidase (GPx), glutathione-peroxidase (GSH-Px), glutathione-reductase, reduced glutathione, total phenol content, Ferric reducing antioxidant power and DPPH radical antioxidant power. Polyphenol oxidase and phenylalanine-ammonium-lyase were determined as enzymatic markers of polyphenol metabolism. Among oxidative stress parameters lipid peroxidation, carbonyl-proteins, hydrogen-peroxide, reactive oxygen species, nitric-oxide and peroxynitrite were determined. Proline, proline-dehydrogenase and glycinebetaine were measured also as parameters of water stress. Cell viability is finally determined as a biological indicator of osmotic stress. It was found that water stress induced reactive oxygen and nitrogen species and lipid peroxidation in leaves of hybrid black poplar and reduced cell viability. Antioxidant enzymes including SOD, GPx, CAT and GSH-Px were induced but total phenol content and antioxidant capacity were reduced by PEG 6000 mediated osmotic stress. The highest biochemical response and adaptive reaction was the increase of proline and GB especially by 200 mOsm PEG. While long term molecular analysis will be necessary to fully address the poplar potentials for water stress adaptation, our results on hybrid black poplar suggest that glycine-betaine, proline and PDH enzyme might be the most important markers of poplar on water stress and that future efforts should be focused on these markers and strategies to enhance their concentration in poplar.


Assuntos
Desidratação , Populus/química , Populus/enzimologia , Populus/metabolismo , Técnicas de Cultura de Tecidos , Água/metabolismo , Antioxidantes/análise , Betaína/metabolismo , Fenômenos Bioquímicos , Biomarcadores , Catalase/metabolismo , Catecol Oxidase/metabolismo , Sobrevivência Celular , Ensaios Enzimáticos , Enzimas/metabolismo , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , Óxido Nítrico/metabolismo , Pressão Osmótica , Estresse Oxidativo , Oxirredutases/metabolismo , Peroxidases/metabolismo , Ácido Peroxinitroso/metabolismo , Fenol/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Prolina/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
4.
Drug Test Anal ; 9(4): 561-570, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27448217

RESUMO

Under European legislation, the use of growth promoters is forbidden in food-producing livestock. The application of unofficial protocols with diverse combinations of veterinary drugs, administered in very low concentrations, hinders reliable detection and subsequent operative prevention. It was observed that nandrolone (anabolic steroid) and ractopamine (ß-adrenergic agonist) are occasionally administered to animals, but little is known about their synergic action when they are administered together. Two specific analytical methods based on liquid chromatography-tandem mass spectrometry have been developed, both of which include hydrolysis of the corresponding conjugates. For the nandrolone method, solid-phase extraction was necessary for the complete elimination of the interferences, while employment of the Quantitation Enhanced Data-Dependent scan mode during MS acquisition of ractopamine enabled the utilization of simple liquid-liquid extraction. The nandrolone method was linear in the range of 0.5-25 ng/mL, while the ractopamine calibration curve was constructed from 0.5 to 1000 ng/mL. The corresponding coefficients of correlations were >0.9907. The lower limit of quantification for both methods was 0.5 ng/mL, followed by overall recoveries >81%. Precisions expressed as relative standard deviations were <17%, while matrix effects were minimal. Urine samples taken at the slaughterhouse from veal calves enrolled in an experimental treatment consisting of intramuscular administration of ß-nandrolone-phenylpropionate accompanied with a ractopamine-enriched diet were analysed. Those methods might be useful for studying the elimination patterns of the administered compounds along with characterization of the main metabolic pathways. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Anabolizantes/urina , Bovinos/urina , Substâncias de Crescimento/urina , Nandrolona/urina , Fenetilaminas/urina , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Inocuidade dos Alimentos , Limite de Detecção , Masculino , Detecção do Abuso de Substâncias/métodos
5.
J Anim Physiol Anim Nutr (Berl) ; 101(5): 893-903, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27080058

RESUMO

The Chianina, one of the oldest and most important cattle breeds of Italy, is now reared all over the world. The Chianina has been known and appreciated since ancient times because, from a nutritional point of view, its meat has no proper rivals. To date, studies have been performed to evaluate the genetic profile of the breed, but knowledge about the chemical profile is generally lacking. Due to the increased interest from farmers regarding breeding of the Chianina, this study proposes a preliminary evaluation of main endogenous urinary corticosteroids (cortisol and cortisone) and most commonly used synthetic one (dexamethasone). Moreover, after recent findings regarding the presence of endogenous prednisolone in the urine of more popular breeds, particular attention was given to analysis of the presence of prednisolone and prednisone, as well. For this aim, the urine samples of 12 young cows and 30 young bulls was collected at the farms and analysed using a fit-for-purpose LC-MS/MS method. The preliminary results of this study show that prednisolone was found only in Chianina females (3 out of 12). Cortisol and cortisone were found at concentrations that showed a high inter-individual variability, and that were higher in female urine compared to that of males.


Assuntos
Bovinos/fisiologia , Cortisona/urina , Hidrocortisona/urina , Prednisolona/urina , Animais , Bovinos/genética , Bovinos/urina , Cromatografia Líquida , Cortisona/química , Feminino , Hidrocortisona/química , Masculino , Estrutura Molecular , Prednisolona/química , Espectrometria de Massas em Tandem
6.
Plant Physiol Biochem ; 105: 242-250, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27116372

RESUMO

This paper is aimed to characterize young poplar plants under the influence of water stress provoked by polyethileneglycol 6000 (PEG 6000). Three polar genotypes (M1, B229, and PE19/66) were grown in hydroponics and subjected to 100 and 200 mOsm PEG 6000 during six days. Polyphenol characterization, two enzymatic markers and antioxidant capacity in leaves and roots were investigated in stressed plants. Total phenol content, ferric reducing antioxidant capacity (FRAP) and DPPH antiradical power (DPPH ARP) were determined for estimating total antioxidant capacity. Polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) were determined as enzymatic markers. Polyphenol characterization of poplar samples was performed by HPLC-PDA analysis. All results were subjected to correlation analysis and principal component analysis (PCA). Inspite of the decrease of total phenol content in investigated genotypes, as well as total antioxidant capacity, some of polyphenols were affected by stress like flavonoids chrysin, myricetine, kaempferol and isoferulic acid in roots of B229 genotype (Populus deltoides). Genotype B229 also showed the increase of antioxidant capacity and PAL activity in root and leaves under stress what could be the indicator of the adaptability of poplar plants to water stress. Significant positive correlations were obtained between PAL, antioxidant capacity as well as phenolic acids among themselves. Chemometric evaluation showed close interdependence between flavonoids, FRAP, DPPH antiradical power and both investigated enzymes of polyphenol metabolism, PAL and PPO.


Assuntos
Antioxidantes/metabolismo , Polifenóis/metabolismo , Populus/metabolismo , Compostos de Bifenilo/química , Desidratação , Recuperação de Fluorescência Após Fotodegradação , Fenilalanina Amônia-Liase/metabolismo , Picratos/química , Extratos Vegetais/química , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Polietilenoglicóis/farmacologia , Populus/efeitos dos fármacos , Populus/enzimologia , Análise de Componente Principal
7.
Chemosphere ; 154: 482-490, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27085062

RESUMO

Bee products, such as honey, are widely consumed as food and consumer interest is currently oriented towards organic foods. Regarding this, the European Commission establishes that the qualification of organic honey and other beekeeping products as being from organic production is closely bound with the characteristics of hive treatments as well as the quality of the environment. Agricultural contamination with pesticides is a challenging problem that needs to be fully addressed, in particular in the field of organic production systems. In this study, the occurrence of different classes of contaminants selected as representative of potential contamination sources were investigated in 59 organic honeys: organochlorines, OCs; organophosphates, OPs; polychlorobiphenyls, PCBs and polybromodiphenylethers, PBDEs. A method based on Accelerated Solvent Extraction with "in line" clean-up and GC-MS/MS detection was developed to detect contaminants. Residues of many pesticides were found in most of the samples investigated. The majority of honey samples contained at least one of the pesticides, even if their concentrations were found to be lower than its MRL. Diazinon, Mevinphos, Coumaphos, Chlorpyrifos and Quinoxyfen were the residues frequently detected in samples coming from the apple and citrus orchard areas. Furthermore, the results of the present study show that the presence of the residue in organic honey may also be affected by the geographical area (e.g. the presence of an agricultural system) confirming honey bee and beehive matrices as appropriate sentinels for monitoring contamination in the environment. The optimised method proved to be simple and rapid, requiring small sample sizes and minimising solvent consumption, due to the ASE having an "in line" clean-up step.


Assuntos
Abelhas , Poluentes Ambientais/análise , Contaminação de Alimentos , Mel/análise , Praguicidas/análise , Compostos Orgânicos Voláteis/análise , Agricultura , Animais , Monitoramento Ambiental/métodos , Itália , Espectrometria de Massas em Tandem/métodos
8.
Chemosphere ; 153: 162-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27016811

RESUMO

Residues of environmental contaminants in food represent a concern in food safety programs. In this study, the distribution of persistent organic pollutants (POPs) were evaluated in 79 tuna samples from FAO areas 51 (Indian Ocean), 71 (Pacific Ocean), 34 (Atlantic Ocean), and 37 (Mediterranean Sea). 6 polychlorinated biphenyls (PCBs), 16 organochlorines (OCs) and 7 polybrominated biphenyl ethers (PBDEs) were selected as representative compounds according to EFSA POPs monitoring guidelines. An analytical method, based on Accelerated Solvent Extraction (ASE), with an "in-line" clean-up step and GC-MS/MS detection, was developed, validated and applied. PCBs were detected in all FAO areas, with a prevalence of 100% for most of them. In the FAO area 37, only, all PBDEs were detected. Only 5 OCs were detected. The results showed that POPs contamination of tuna reflects FAO area contamination; in particular FAO area 37 was the most polluted. Moreover, tuna muscle was an appropriate matrix for monitoring contamination and for obtaining information about food safety.


Assuntos
Éteres Difenil Halogenados/metabolismo , Hidrocarbonetos Clorados/metabolismo , Atum/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Oceanos e Mares , Bifenilos Policlorados/metabolismo , Espectrometria de Massas em Tandem
9.
Anal Chim Acta ; 852: 137-45, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25441890

RESUMO

The presence of ß-boldenone II phase metabolites and prednisolone in urine samples, owing to endogenous or natural origin or illicit treatment, is under debate within the European Union. The detection of ß-boldenone conjugates, α-boldenone conjugates at concentrations higher than 2 ng mL(-1) and prednisolone above the cut-off level of 5 ng mL(-1) in urine have been, until now, critical in deciding if illegal drug use has occurred. The use of urine sometimes is not entirely satisfactory, especially when the drug is administrated at low doses or when its metabolic conversion is very fast. This subsequently would hamper its detection in urine. The introduction of a new, advantageous matrix where the illicit treatment can be investigated would be highly appreciated. In this study, we have developed and validated a simple and unique immunoaffinity clean-up procedure, which was applied to bovine bile samples, followed by two different analytical liquid chromatography-electrospray-tandem mass spectrometry methods. The first method tests androstadienedione, α- and ß-boldenone sulphate, glucuronate and related free forms, while the other method assays prednisolone, prednisone, dexamethasone, cortisone, and cortisol. The methods were validated according to European Commission Decision 2002/657/EC. The evaluated parameters were linearity, specificity, precision (repeatability and intra-laboratory reproducibility), recovery, decision limit and detection capability. The decision limits (CCα) were between 0.38 and 0.45 ng mL(-1) for anabolic steroids, and 0.13 and 0.15 ng mL(-1) as far as corticosteroids were concerned. Intra- and inter-day repeatability was below 15.8 and 19.9% for all analytes, respectively. The methods were applied to the analysis of some bile samples collected from untreated young bulls in order to investigate the presence of the studied steroids in this matrix.


Assuntos
Corticosteroides/análise , Androstadienos/análise , Bile/química , Bovinos , Espectrometria de Massas em Tandem/métodos , Testosterona/análogos & derivados , Animais , Bovinos/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Glucuronídeos/análise , Técnicas de Imunoadsorção , Limite de Detecção , Masculino , Testosterona/análise
10.
J Dairy Sci ; 97(7): 4029-42, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24835972

RESUMO

Hyperuricemia is a biochemical hallmark of gout, renal urate lithiasis, and inherited purine disorders, and may be a result of enormous ATP breakdown or purine release as a result of cardiovascular disease, hypertension, kidney disease, eclampsia, obesity, metabolic syndrome, psoriasis, tumor lysis syndrome, or intense physical training. The beneficial role of dairy products on hyperuricemia management and prevention is well documented in the literature. The primary aim of our experimental study was to examine the effect of milk dietary regimen (commercial 1.5% fat UHT milk or patented depurinized milk) compared with allopurinol therapy on experimental hyperuricemia induced by oxonic acid in rats. Principal component analysis was applied on a data set consisting of 11 variables for 8 different experimental groups. Among the 11 parameters measured (plasma uric acid and the liver parameters NFκB-p65, Akt kinase/phospho-Akt kinase, ERK kinase/phospho-ERK kinase, IRAK kinase/phospho IRAK kinase, p38/phospho-p38, and DNase), Akt/phospho Akt and ERK/phospho-ERK signaling were extracted as the most discriminating. We also compared the content of various potentially toxic compounds (sulfur compounds, ketones, aldehydes, alcohols, esters, carboxylic acids, and phthalates) in untreated commercial milk and depurinized milk. Of all the compounds investigated in this study that were observed in commercial milk (24 volatile organic compounds and 4 phthalates), 6 volatile organic compounds were not detected in depurinized milk. For almost all of the other compounds, significant decreases in concentration were observed in depurinized milk compared with commercial milk. In conclusion, a depurinized milk diet may be recommended in nutritional treatment of primary and secondary hyperuricemia to avoid uric acid and other volatile, potentially toxic compounds that may slow down liver regeneration and may induce chronic liver diseases.


Assuntos
Alopurinol/farmacologia , Alopurinol/uso terapêutico , Endonucleases/metabolismo , Hiperuricemia/dietoterapia , Fígado/enzimologia , Leite/metabolismo , NF-kappa B/metabolismo , Ração Animal/análise , Animais , Dieta , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Hiperuricemia/induzido quimicamente , Hiperuricemia/tratamento farmacológico , Hiperuricemia/enzimologia , Fígado/efeitos dos fármacos , Masculino , Leite/química , Ácido Oxônico/toxicidade , Distribuição Aleatória , Ratos , Ratos Wistar
11.
Int Arch Allergy Immunol ; 160(1): 47-55, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22948171

RESUMO

BACKGROUND: Anti-sperm antibodies (ASA) have been described to be involved in immunological infertility. A possible antigen for ASA is the human cysteine-rich secretory protein 2 (CRISP-2), a sperm surface protein important in sperm-oocyte interaction. Furthermore, anti-CRISP-2 antibodies were shown to decrease fertility rates in vitro. Recently, we have reported cross-reacting antibodies recognizing CRISP-2 and antigen 5 from yellow jacket venom (Ves v 5) in human serum. METHODS: Here, we investigated anti-Ves v 5 and CRISP-2 antibodies in sera from two groups of donors: MAR+ and MAR- patients. RESULTS: A higher incidence of allergy against hymenoptera venom was found in MAR+ patients. Interestingly, affinity-purified ASA from MAR+ patients' sera reacted against both Ves v 5 and CRISP-2, leading to sperm immobilization. Immunofluorescence analysis showed that ASA bound to the sperm surface, including the head part where CRISP-2 is localized. CONCLUSION: Taken together, these results showed a higher incidence of antibodies cross-reacting with Ves v 5 and CRISP-2 in MAR+ patients. This leads to the hypothesis that MAR+ patients may have a higher risk to develop wasp allergy.


Assuntos
Alérgenos/imunologia , Anticorpos/sangue , Glicoproteínas/imunologia , Espermatozoides/imunologia , Venenos de Vespas/imunologia , Adulto , Animais , Moléculas de Adesão Celular , Teste de Coombs , Reações Cruzadas , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Vespas/imunologia
12.
Neuroscience ; 219: 175-82, 2012 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-22677204

RESUMO

UNLABELLED: Multiple sclerosis (MS) is characterized by inflammatory process associated with nitric oxide (NO) and the related species production in CNS, which can nitrosylate protein thiols and modulate their structure and functions, also reducing the CNS content of redox active compounds, such as glutathione (GSH). We have evaluated the relationships between S-nitrosothiols (RSNO) and GSH in the experimental model of MS - experimental autoimmune encephalomyelitis (EAE), during the treatment with inducible NO synthase inhibitor - aminoguanidine (AG) and thiol donor molecule - N-acetyl-L-cysteine (NAC). MATERIAL AND METHODS: EAE was induced by myelin basic protein, dissolved in phosphate-buffered saline (PBS), emulsified in the complete Freund's adjuvant (CFA) followed by injections of Pertussis toxin. Animals assigned to the control (PBS), EAE, CFA, EAE+AG, AG, EAE+NAC and NAC groups were scored daily for the clinical signs of EAE. RSNO and GSH were evaluated in whole encephalitic mass and cerebellum. RESULTS: RSNO concentration was increased in EAE-untreated animals compared to the AG and NAC-treated EAE animals (p<0.05). Also, during the treatment with AG and NAC, GSH concentration was increased compared to the untreated animals (p<0.05). The EAE clinical signs were reduced in EAE-treated animals compared to the other groups (p<0.05). CONCLUSION: The findings of our work suggest a potential role of RSNO and GSH in early clinical presentation of experimental MS, that might be also useful as predictive parameters for MS treatment directed to increased GSH and thiol pool in CNS.


Assuntos
Encefalomielite Autoimune Experimental/metabolismo , Glutationa/metabolismo , S-Nitrosotióis/metabolismo , Animais , Biomarcadores , Encéfalo/metabolismo , Encéfalo/patologia , Encefalomielite Autoimune Experimental/patologia , Inibidores Enzimáticos/farmacologia , Feminino , Sequestradores de Radicais Livres/farmacologia , Imuno-Histoquímica , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley
13.
Amino Acids ; 43(6): 2293-300, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22555650

RESUMO

Elevated plasma concentrations of asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) were found in various clinical settings including coronary heart disease. To assess ADMA and SDMA diagnostic validity in patients with different stages of ischemic heart disease, we studied these markers in patients having stable angina pectoris (SAP), unstable angina (USAP), and acute myocardial infarction (AMI). The results were compared with the values of healthy individuals. Plasma ADMA and SDMA levels were measured by high-performance liquid chromatography. In all patient groups both markers were significantly elevated in comparison with control ones (p < 0.001). In SAP patients, the median ADMA value was 0.75 (0.31-2.73) µmol/L, and SDMA 1.11 (0.69-0.1.42) µmol/L, in USAP patients, the marker values were 0.94 (0.34-3.13) µmol/L and 1.23 (0.88-4.72) µmol/L, and in AMI patients, 0.98 (0.48-2.01) µmol/L and 1.26 (0.75-2.93) µmol/L, while in healthy subjects they were 0.31 (0.17-0.87) µmol/L and 0.29 (0.20-0.83) µmol/L, respectively. SDMA was found significantly different in SAP and AMI patients (p < 0.05). Diagnostic accuracy was determined by receiver operating characteristic (ROC) curve analysis. The highest area under the ROC (AUC) for ADMA was obtained in AMI patients (0.976), while for SDMA in USAP patients (1.000). There was no significant difference between the AUCs. The greatest sensitivity and specificity were found in the USAP group (95.65 and 96.30 % for ADMA, and 100 % for each characteristic of SDMA). Considering these results, SDMA showed better clinical accuracy in assessing ischemic disease, where it could be used as a valid marker and a therapeutic target.


Assuntos
Arginina/análogos & derivados , Isquemia Miocárdica/sangue , Arginina/sangue , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico
14.
J Fluoresc ; 22(4): 1189-99, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22534954

RESUMO

In this study, we have investigated the fluorescence properties of SYBR Green I (SG) dye and its interaction with double-stranded DNA (dsDNA). SG/dsDNA complexes were studied using various spectroscopic techniques, including fluorescence resonance energy transfer and time-resolved fluorescence techniques. It is shown that SG quenching in the free state has an intrinsic intramolecular origin; thus, the observed >1,000-fold SG fluorescence enhancement in complex with DNA can be explained by a dampening of its intra-molecular motions. Analysis of the obtained SG/DNA binding isotherms in solutions of different ionic strength and of SG/DNA association in the presence of a DNA minor groove binder, Hoechst 33258, revealed multiple modes of interaction of SG inner groups with DNA. In addition to interaction within the DNA minor groove, both intercalation between base pairs and stabilization of the electrostatic SG/DNA complex contributed to increased SG affinity to double-stranded DNA. We show that both fluorescence and the excited state lifetime of SG dramatically increase in viscous solvents, demonstrating an approximate 200-fold enhancement in 100 % glycerol, compared to water, which also makes SG a prospective fluorescent viscosity probe. A proposed structural model of the SG/DNA complex is compared and discussed with results recently reported for the closely related PicoGreen chromophore.


Assuntos
DNA/metabolismo , Fluorescência , Compostos Orgânicos/química , Compostos Orgânicos/metabolismo , Benzotiazóis , DNA/química , Diaminas , Conformação de Ácido Nucleico , Quinolinas , Soluções , Espectrometria de Fluorescência , Eletricidade Estática , Termodinâmica , Viscosidade
15.
J Anim Physiol Anim Nutr (Berl) ; 96(4): 640-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21740468

RESUMO

Hyperuricaemia and gout are closely related, but hyperuricaemia is an independent risk factor for endothelial damage, autoinflammation and haemodynamic abnormalities. Milk, generally known as a 'purine-free diet', is an essential protein source for patients suffering from hyperuricaemia and gout. As milk still contains different purine ribonucleotides, the new product, depurinized milk, almost free of purine nucleotides and uric acid, was produced. The potential effect of depurinized milk diet on serum uric acid (SUA) level, lipid parameters and blood haematological parameters was explored in rats after 72 h and 15 days, in relation to standard laboratory chow or the untreated milk diet. The beneficial effect on SUA was achieved when depurinized milk draught was given instead of standard chow for 72 h [28.39 ± 4.76 µm; p < 0.001 vs. standard diet (STD) 47.6 ± 6.12, vs. untreated milk diet 31.55 ± 8.50; p < 0.05] or as a supplement for STD for 15 days experiment (35.38 ± 6.40 µm; p < 0.05 vs. STD only 48.05 ± 4.32; vs. untreated milk + STD 46.02 ± 9.48). Depurinized milk diet significantly decreased the low density lipoproteins/high density lipoproteins (LDL/HDL) ratio (p < 0.001), triglycerides (p < 0.05) and leucocyte count (p < 0.001), while both milk draughts enhanced haemoglobin concentration (p < 0.01). In conclusion, considering the detrimental effect of persisting hyperuricaemia, the depurinized milk draught may meet the demand of healthy dairy product for population under hyperuricaemic risk.


Assuntos
Ração Animal/análise , Dieta/veterinária , Lipídeos/sangue , Leite/química , Purinas/química , Ácido Úrico/sangue , Animais , Feminino , Proteínas do Leite , Ratos , Ratos Wistar
16.
Minerva Anestesiol ; 76(5): 325-33, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20395894

RESUMO

AIM: Asymmetric and symmetric dimethylarginines (ADMA and SDMA, respectively) are protein breakdown markers; both compete with arginine for cellular transport and both are excreted in urine. Moreover, ADMA is a non-selective inhibitor of nitric oxide (NO) synthase that is metabolized by a specific hydrolase in which the activity during stress remains controversial. While an increase in ADMA is known to be associated with adverse events, little is known about SDMA. We investigated plasma ADMA and SDMA levels during ICU stay to reveal the time course of endogenous NO inhibition in patients with sepsis. METHODS: A post hoc analysis from a prospective random controlled trial conducted in three ICUs was performed to study the pathophysiological pathways of sepsis. ADMA, SDMA, the ratio of ADMA/SDMA (a marker of ADMA catabolism), arginine, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and C reactive protein (CRP) were measured on days 1, 3, 6, 9, 12 and at discharge in 72 consecutive severely septic patients. RESULTS: Fasting basal glycemia, creatinine, IL-6, TNF-alpha, CRP, ADMA, and SDMA were higher than normal. The ADMA/SDMA ratio was decreased by 50%, and arginine levels were low. ADMA levels were related to the total Sequential Organ Failure Assessment (SOFA) scores and arginine levels, and inversely related to IL-6 and CRP levels. SDMA levels were related to Simplified Acute Physiologic Scores II (SAPS II), SOFA scores, blood urea, creatinine, and arginine levels. The ADMA/SDMA ratio was inversely related to IL-6 levels. In 58 ICU survivors, creatinine, IL-6, and CRP levels decreased over time; ADMA levels increased, SDMA levels remained stable, and the ADMA/SDMA ratio increased. In 14 non-survivors, creatinine, IL-6, TNF-alpha, CRP, and ADMA levels were stable, whereas the SDMA levels increased and the ADMA/SDMA ratio remained low. In both ICU survivors and non-survivors, the levels on the last ICU day confirmed the data trends. SDMA, but not ADMA, was associated with ICU mortality. CONCLUSION: ADMA catabolism appears to be activated by inflammation; its increase during the advanced septic phase in surviving patients may suggest an endogenous inhibition of NO synthesis during the full-blown septic phase. In severe sepsis, SDMA, but not ADMA, appears to be a marker of alterations in vital functions and mortality.


Assuntos
Arginina/análogos & derivados , Óxido Nítrico/antagonistas & inibidores , Sepse/tratamento farmacológico , Idoso , Arginina/efeitos adversos , Arginina/sangue , Arginina/uso terapêutico , Biomarcadores , Análise Química do Sangue , Cuidados Críticos , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Sobrevida
17.
Pharmazie ; 64(10): 656-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19947168

RESUMO

Quantitative analyses and investigation of antioxidant activity of herb and dry ethanolic extracts of five species from Ericaceae family (Arbutus unedo L., Bruckentalia spiculifolia Rchb., Calluna vulgaris Salisb., Erica arborea L. and Erica carnea L.) were performed. Total polyphenols, tannins and flavonoids were determined spectrophotometrically and arbutin content was measured both spectrophotometrically and by HPLC coupled with DAD detection. Antioxidative properites of the ethanolic extracts were tested by means of FRAP (total antioxidant capacity), lipid peroxidation and DPPH free radical scavenging activity. A significant amount of arbutin was detected only in Arbutus unedo. All samples investigated showed excellent antioxidant activity. The best inhibition of lipid peroxidation has been shown by Bruckentalia spiculifolia herb extract (62.5 microg/ml; more than 95%), which contained the highest amount of flavonoids (11.79%). The highest scavenging activity was obtained with leave extract of Arbutus unedo (IC50 = 7.14 microg/ml). The leaves of A. unedo contained a small amount of flavonoids but high content of non-tannins polyphenols.


Assuntos
Antioxidantes/análise , Arbutina/análise , Ericaceae/química , Antioxidantes/farmacologia , Arbutina/farmacologia , Compostos de Bifenilo , Cromatografia Líquida de Alta Pressão , Compostos Férricos/química , Flavonoides/análise , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Hidroquinonas/química , Peroxidação de Lipídeos/efeitos dos fármacos , Oxidantes/química , Fenóis/análise , Fenóis/farmacologia , Picratos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis , Espectrofotometria Ultravioleta , Taninos/análise , Taninos/química
18.
Exp Clin Endocrinol Diabetes ; 117(9): 480-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19358092

RESUMO

The immune response can be triggered by molecules derived from microorganisms (PAMP) or from molecules derived from damaged or dead host cells, known as the damage-associated molecular-pattern molecules (DAMP). Their immune effects are accompanied by altered redox environment. The level of stable end products of nitric oxide (NO)- plasma nitrate and nitrite (NOx), carbonyl groups (PCO) and nitrotyrosine (NTY), in relation to the metabolism of dsRNAs (poly I:C and poly A:U) and xanthine oxidase (XO activity), in plasma of type2 diabetic patients was determined. Thirty-six patients with type 2 diabetes (age group 34-66 years, 19 male and 17 female) were allocated to the study. Diabetic patients had a significantly higher level of plasma NOx products, NTY and PCO, fructosamine (FA) and XO activity indicating about altered redox environment. The concentration of circulating ribonucleic acids (CNAs) was significantly higher in type 2 diabetic patients, which was accompanied by a significantly decreased activity of RNase against double stranded RNA forms (poly I:C and poly A:U), compared to control samples. To determine whether CNAs, as possible DAMP molecules, are capable of exerting effect on inflammatory and host antiviral response, the effect of isolated CNAs on NF-kappaB, Bcl-2, Bax, MDA-5 and IRF-3 regulation was evaluated in culture of fresh isolated thymocytes. Circulating nucleic acids isolated from type 2 diabetic patients were able to upregulate NF-kappaB more than control RNA samples. In the same experimental conditions the mild Bcl-2 upregulation, followed by the marked Bax upregulation, was demonstrated. Since the Bcl-2/Bax ratio was lower in type 2 diabetic samples, obtained results may implicate that CNAs may exert proapoptotic response in type 2 diabetes. The CNAs isolated from diabetic patients were able to downregulate MDA-5 and IRF-3, very important subjects of the surveillance and cellular anti-viral response. The major findings of the present study are that impaired dsRNA metabolism may lead to increased level of different sized RNAs in type 2 diabetic patients. Acting as possible DAMP molecules, they may contribute to higher susceptibility of immune cells to inflammatory cascade via NF-kappaB activation, and possible MDA-5/IRF-3 axis downregulation, what may have an influence on further ineffective response against different pathogens.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Inflamação/metabolismo , Estabilidade de RNA/genética , RNA de Cadeia Dupla/metabolismo , Adulto , Idoso , Animais , Glicemia/metabolismo , Células Cultivadas , RNA Helicases DEAD-box/metabolismo , Diabetes Mellitus Tipo 2/genética , Feminino , Imunofluorescência , Humanos , Inflamação/genética , Fator Regulador 3 de Interferon/metabolismo , Helicase IFIH1 Induzida por Interferon , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Nitritos/sangue , Ácidos Nucleicos/sangue , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA de Cadeia Dupla/genética , Ratos , Timo/citologia , Timo/metabolismo , Tirosina/análogos & derivados , Tirosina/sangue , Xantina Oxidase/sangue , Proteína X Associada a bcl-2/metabolismo
19.
Amino Acids ; 32(1): 127-31, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16699819

RESUMO

The existing interrelation in metabolic pathways of L-arginine to polyamines, nitric oxide (NO) and urea synthesis could be affected in sepsis, inflammation, intoxication and other conditions. The role of polyamines and NO in the toxic effect of mercury chloride on rat liver function was studied. Administration of mercury chloride for 24 h led to significantly elevated plasma activities of Alanine transaminase (ALT) and Aspartate transaminase (AST). Malondyaldehyde (MDA) levels were unaffected (p > 0.05) and arginase activity was significantly decreased (p < 0.05) while nitrate/nitrite production was significantly elevated (p < 0.001) in liver tissue. Polyamine oxidase (PAO) and diamine oxidase (DAO) activities, enzymes involved in catabolism of polyamines, were decreased. L-arginine supplementation to intoxicated rats potentiated the effect of mercury chloride on NO production and it was ineffective on arginase activity. Results obtained in this study show that mercury chloride-induced toxicity leads to abnormally high levels of ALT and AST that may indicate liver damage with the involvement of polyamine catabolic enzymes and NO.


Assuntos
Amina Oxidase (contendo Cobre)/metabolismo , Arginase/metabolismo , Arginina/farmacologia , Falência Hepática/enzimologia , Cloreto de Mercúrio/toxicidade , Óxido Nítrico Sintase/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Animais , Arginina/agonistas , Sinergismo Farmacológico , Falência Hepática/induzido quimicamente , Falência Hepática/patologia , Masculino , Cloreto de Mercúrio/agonistas , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley , Ureia/metabolismo , Poliamina Oxidase
20.
Allergy ; 60(11): 1446-50, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16197480

RESUMO

BACKGROUND: Differential leukocyte counts are of proven clinical value, but information about basophil counts in normal and disease conditions is scarce although basophils are regarded as key effector cells in allergy. AIMS: To establish and validate flowcytometric methods for counting basophils in peripheral human blood, to determine reference values, and to examine the accuracy of two widely used hematology analyzers. METHODS: Basophils were measured in whole blood by flowcytometry after staining with antibodies against the IL-3-receptor (CD123) or the eotaxin-receptor (CCR3) combined with other markers used for gating or validation purposes. RESULTS: The basophil percentages in 95 healthy adults showed an excellent correlation between the two independent flowcytometric methods, demonstrating that both are accurate and precise. The most robust maker is CCR3, which seems to be sufficient to specifically identify basophils. Normal values of relative and absolute blood basophils counts were 0.22-1.28% and 0.014-0.087 G/L (95% reference intervals), respectively. Basophil counts measured with two hematology analyzers Coulter GEN-S and ADVIA-120 showed no correlation between these instruments. Comparing the data obtained by flowcytometry and the analyzers demonstrate that basophil counts of the GEN-S are erratic, while the ADVIA-120 gives at least an estimation of true basophil numbers. CONCLUSIONS: We provide a solid description and validation of a novel and rapid method for the flowcytometric enumeration of basophil in whole blood. The fact that the most heavily used Hematology autoanalyzer gives completely erroneous results could explain why basophils counts have not yet received recognition as a clinically useful diagnostic marker.


Assuntos
Basófilos/imunologia , Citometria de Fluxo/métodos , Testes Hematológicos/normas , Contagem de Leucócitos/métodos , Adolescente , Adulto , Anticorpos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores de Interleucina-3/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Coloração e Rotulagem
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