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1.
Clin Biochem ; 95: 49-53, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34077758

RESUMO

BACKGROUND: The management of affected results in haemolysed samples (HS) is debated. In an infant-maternity setting, for reporting interfered test results, we provided the result itself, the degree of haemolysis (as free haemoglobin concentration), and a warning recommending sample recollection. We investigated the impact of this approach on sample quality and clinicians' decision-making. METHODS: Free haemoglobin was measured on Beckman Coulter AU680 as haemolytic index. We estimated the total HS number, the clinical wards more affected by HS, the most interfered analytes, and the retesting rate of interfered tests, by comparing data from Apr-Dec 2017, the period just after the introduction of the new policy, vs. Apr-Dec 2018. RESULTS: One year after the new report introduction, a significant HS decrease (5.8% vs. 7.8%, P < 0.001) was detected, together with a reduction of the frequency by which haemolysis affected results. The most affected wards, i.e., Paediatric and Neonatal Intensive Care Units, showed an improvement in sample quality (HS rate, 30.6% to 16.1%, P < 0.001, and 25.2% to 20.9%, P = 0.048, respectively). We noted a significant decrease in retesting after an alerted result for aspartate aminotransferase, magnesium, potassium, conjugated bilirubin, and lactate dehydrogenase. CONCLUSIONS: Our approach led to a HS decrease, suggesting that the provided report could be a driving force for improvement of phlebotomy quality, also helping clinicians in deciding if retesting is essential or not.


Assuntos
Análise Química do Sangue/normas , Coleta de Amostras Sanguíneas/normas , Química Clínica/métodos , Química Clínica/normas , Hemólise , Maternidades , Manejo de Espécimes/normas , Coleta de Amostras Sanguíneas/estatística & dados numéricos , Hemoglobinas/análise , Humanos , Obstetrícia , Quartos de Pacientes , Manejo de Espécimes/estatística & dados numéricos
2.
J Clin Lab Anal ; 34(4): e23130, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31876061

RESUMO

BACKGROUND: Coenzyme Q10 (CoQ10) supplementation can improve cognition in patients with Alzheimer's disease (AD) and AD transgenic model mice. To ameliorate the discomfort that patients with AD suffer after several blood extractions, a non-invasive method for detecting urine CoQ10 levels needs to be established. METHODS: Here, we developed a new technique of fluorescence spectrophotometry with ethyl cyanoacetate (FS-ECA), on the basis of the principle that the chemical derivative obtained from the interaction between CoQ10 and ECA was detected by a fluorescence detector at λex/em  = 450/515 nm. As a standard reference method, the same batches of the clinical samples were analyzed by high-performance liquid chromatography with an ultraviolet detector (HPLC-UV) at 275 nm. RESULTS: The limits of detection (LOD) and limits of quantization (LOQ) (serum: 0.021 and 0.043 mg/L; urine: 0.012 and 0.025 mg/L) determined by the FS-ECA method were similar to that obtained through HPLC-UV (serum: 0.017 and 0.035 mg/L; urine: 0.012 and 0.025 mg/L). More importantly, this new FS-ECA technique as well as the conventional HPLC-UV method could detect a marked difference in urine CoQ10 levels between AD and controls. CONCLUSION: Our findings suggest that this non-invasive method for quantifying urine CoQ10 potentially replaces HPLC to detect blood CoQ10.


Assuntos
Química Clínica/métodos , Ubiquinona/análogos & derivados , Acetatos/química , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/urina , Cromatografia Líquida de Alta Pressão , Fluorescência , Humanos , Limite de Detecção , Espectrometria de Fluorescência , Temperatura , Fatores de Tempo , Ubiquinona/sangue , Ubiquinona/urina
3.
J Zhejiang Univ Sci B ; 20(3): 264-272, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30829013

RESUMO

ß-Glucosidase activity assays constitute an important indicator for the early diagnosis of neonatal necrotizing enterocolitis and qualitative changes in medicinal plants. The drawbacks of the existing methods are high consumption of both time and reagents, complexity in operation, and requirement of expensive instruments and highly trained personnel. The present study provides a simplified, highly selective, and miniaturized glucometer-based strategy for the detection of ß-glucosidase activity. Single-factor experiments showed that optimum ß-glucosidase activity was exhibited at 50 °C and pH 5.0 in a citric acid-sodium citrate buffer when reacting with 0.03 g/mL salicin for 30 min. The procedure for detection was simplified without the need of a chromogenic reaction. Validation of the analytical method demonstrated that the accuracy, precision, repeatability, stability, and durability were good. The linear ranges of ß-glucosidase in a buffer solution and rat serum were 0.0873-1.5498 U/mL and 0.4076-2.9019 U/mL, respectively. The proposed method was free from interference from ß-dextranase, snailase, ß-galactosidase, hemicellulase, and glucuronic acid released by baicalin. This demonstrated that the proposed assay had a higher selectivity than the conventional dinitrosalicylic acid (DNS) assay because of the specificity for salicin and unique recognition of glucose by a personal glucose meter. Miniaturization of the method resulted in a microassay for ß-glucosidase activity. The easy-to-operate method was successfully used to detect a series of ß-glucosidases extracted from bitter almonds and cultured by Aspergillus niger. In addition, the simplified and miniaturized glucometer-based assay has potential application in the point-of-care testing of ß-glucosidase in many fields, including medical diagnostics, food safety, and environmental monitoring.


Assuntos
Química Clínica/instrumentação , Glucose/análise , beta-Glucosidase/análise , Animais , Aspergillus niger , Calibragem , Celulase/análise , Química Clínica/métodos , Dextranase/análise , Enterocolite Necrosante/sangue , Enterocolite Necrosante/diagnóstico , Desenho de Equipamento , Flavonoides/análise , Ácido Glucurônico/análise , Glucuronidase/análise , Glicosídeo Hidrolases/análise , Concentração de Íons de Hidrogênio , Modelos Lineares , Complexos Multienzimáticos/análise , Plantas Medicinais , Poligalacturonase/análise , Ratos , Reprodutibilidade dos Testes , beta-Galactosidase/análise
4.
J Ethnopharmacol ; 210: 242-253, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-28648929

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The dried ripe seeds of Nux Vomica (Strychnos nux-vomica L.), a traditional Chinese medicine, have been used to treat multifarious symptoms. However, the clinical applications of Nux Vomica are limited by its severe toxicity. In this study, Nux Vomica was subjected to nuclear magnetic resonance (NMR) metabonomics and pathological examination to determine relevant biomarkers in target organs and to explain the underlying toxicity mechanism. MATERIALS AND METHOD: Thirty-six male Sprague-Dawley rats were randomly divided into three groups of twelve rats. The control group was oral gavaged with distilled water, and two experiment groups were treated with Nux Vomica at a dose of 0.315 and 0.630g/kg body weight. On days 14 and 21, serum, urine, liver and kidney tissues were collected for histopathological examination, biochemical analysis and 1H-NMR analysis. RESULTS: The metabolites changes of rats treated with Nux Vomica are obviously differ from that of controls. In serum, low-dose group compared with control shows the significantly changes included elevated concentration of glucose, TMAO, and creatine, with decreased lipids, 3-HB, lactate, and unsaturated fatty acid. Change in taurine was only observed in the separation comparison of high-dose group and control. In urine, the variation metabolites included elevations in glucose, creatine, and TMAO as well as decreased lactate, succinate, α-ketoglutaric acid, citrate and hippurate in low-dose group compared with control. Only alanine and creatine were decreased significantly in high-dose group compared with control. CONCLUSION: Nux Vomica induced disruptions in glycolysis, lipid and amino acid metabolism, and toxic effects were aggravated in liver and kidney tissues as dosing time was prolonged. 1H NMR-based metabonomics combined with biochemical and histopathological methods can be applied to elucidate the toxicity mechanism of Nux Vomica decoction that caused liver and kidney injuries in rats.


Assuntos
Medicamentos de Ervas Chinesas/toxicidade , Metabolômica/métodos , Extratos Vegetais/toxicidade , Strychnos nux-vomica/química , Aminoácidos/efeitos dos fármacos , Aminoácidos/metabolismo , Animais , Química Clínica/métodos , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Glicólise/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Medicina Tradicional Chinesa/efeitos adversos , Extratos Vegetais/administração & dosagem , Espectroscopia de Prótons por Ressonância Magnética , Ratos , Ratos Sprague-Dawley , Sementes , Fatores de Tempo
5.
PLoS One ; 7(9): e44331, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22984493

RESUMO

OBJECTIVE: The aim is to characterize subgroups or phenotypes of rheumatoid arthritis (RA) patients using a systems biology approach. The discovery of subtypes of rheumatoid arthritis patients is an essential research area for the improvement of response to therapy and the development of personalized medicine strategies. METHODS: In this study, 39 RA patients are phenotyped using clinical chemistry measurements, urine and plasma metabolomics analysis and symptom profiles. In addition, a Chinese medicine expert classified each RA patient as a Cold or Heat type according to Chinese medicine theory. Multivariate data analysis techniques are employed to detect and validate biochemical and symptom relationships with the classification. RESULTS: The questionnaire items 'Red joints', 'Swollen joints', 'Warm joints' suggest differences in the level of inflammation between the groups although c-reactive protein (CRP) and rheumatoid factor (RHF) levels were equal. Multivariate analysis of the urine metabolomics data revealed that the levels of 11 acylcarnitines were lower in the Cold RA than in the Heat RA patients, suggesting differences in muscle breakdown. Additionally, higher dehydroepiandrosterone sulfate (DHEAS) levels in Heat patients compared to Cold patients were found suggesting that the Cold RA group has a more suppressed hypothalamic-pituitary-adrenal (HPA) axis function. CONCLUSION: Significant and relevant biochemical differences are found between Cold and Heat RA patients. Differences in immune function, HPA axis involvement and muscle breakdown point towards opportunities to tailor disease management strategies to each of the subgroups RA patient.


Assuntos
Artrite Reumatoide/diagnóstico , Artrite Reumatoide/metabolismo , Metabolômica/métodos , Adulto , Idoso , Artrite Reumatoide/classificação , Proteína C-Reativa/biossíntese , Química Clínica/métodos , Temperatura Baixa , Feminino , Temperatura Alta , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Medicina Tradicional Chinesa , Pessoa de Meia-Idade , Análise Multivariada , Fenótipo , Sistema Hipófise-Suprarrenal/fisiopatologia , Medicina de Precisão/métodos , Fator Reumatoide/sangue , Reumatologia/métodos , Inquéritos e Questionários
6.
Curr Pharm Des ; 18(21): 2996-3006, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22564294

RESUMO

The 'omics' technologies represent analytical approaches that have a holistic view on molecules such as genes, transcripts, proteins and metabolites constituting a cell, tissue or organism. The profiling of genes, transcripts and proteins has been referred to as genomics, transcriptomics and proteomics. Finally, there is the youngest and most rapidly increasing of the "omics" disciplines: metabolomics. Metabolomics appears to be a new, very useful tool in neonatology, especially in the fields of pharma-metabolomics and nutri- metabolomics. Since it appears to be predictive and preventive, it can be considered the 'new clinical chemistry' for personalized neonatal medicine. At present, the use of metabolomics in neonatology is still in the pioneering phase. In clinical practice, only a limited number of metabolites are routinely measured in the biofluids of newborns by conventional analytical methods to study the metabolic status of the organism. However, the management of sick or preterm newborns might be improved if more information on perinatal/ neonatal maturational processes and their metabolic background were available. The aim of this review, after a general introduction on pharma-metabolomics, is to present the potential of NMR-based metabolomic analysis of newbom urine in neonatology in the field of pharmacology.


Assuntos
Descoberta de Drogas/tendências , Doenças do Recém-Nascido/tratamento farmacológico , Metabolômica/tendências , Neonatologia/métodos , Medicina de Precisão/tendências , Química Clínica/métodos , Química Clínica/tendências , Descoberta de Drogas/métodos , Tratamento Farmacológico/tendências , Previsões , Humanos , Recém-Nascido , Doenças do Recém-Nascido/metabolismo , Neonatologia/tendências , Teoria de Sistemas
7.
Biochem Med (Zagreb) ; 21(2): 160-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22135856

RESUMO

INTRODUCTION: Lipemic specimens are a common and frequent, but yet unresolved problem in clinical chemistry, and may produce significant interferences in the analytical results of different biochemical parameters. MATERIAL AND METHODS: The aim of this study was to examine the effect of lipid removal using ultracentrifugation of lipemic samples, on some routine biochemistry parameters. Among all the samples obtained daily in our laboratory, the ones which were visibly muddy were selected and underwent to a process of ultracentrifugation, being determined a variety of biochemical tests before and after ultracentrifugation. A total of 110 samples were studied. RESULTS: We found significant differences in all the parameters studied except for total bilirubin, glucose, gamma-glutamyl transferase (GGT) and aspartate aminotransferase (AST). The greatest differences in the parameters analyzed were found in the concentration of alanine aminotransferase (ALT) (7.36%) and the smallest ones in the concentration of glucose (0.014%). Clinically significant interferences were found for phosphorus, creatinine, total protein and calcium. CONCLUSION: Lipemia causes clinically significant interferences for phosphorus, creatinine, total protein and calcium measurement and those interferences could be effectively removed by ultracentrifugation.


Assuntos
Química Clínica/métodos , Hiperlipidemias/sangue , Triglicerídeos/sangue , Ultracentrifugação/métodos , Bilirrubina/sangue , Proteínas Sanguíneas/análise , Cálcio/sangue , Creatinina/sangue , Enzimas/sangue , Humanos , Fósforo/sangue
8.
Clin Biochem ; 44(12): 1000-4, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21635881

RESUMO

OBJECTIVES: To investigate the analytical interference of drugs in urinary protein and to estimate the lowest interfering concentrations. DESIGN AND METHODS: Drug supplemented urine samples were compared to the control with two reagent strips and the total protein was determined using Pyrogallol Red-Molybdate (PRM). RESULTS: False-positive interferences occurred with Multistix 10 SG for hydroxychloroquine, levofloxacin and ofloxacin. No interference was observed with Combur 10 Test M. Statistically significant false-positive interferences were observed in the PRM assay with all tested drugs, and lowest interfering concentrations were mostly above estimated therapeutic concentrations. The PRM assay "confirmed" the results of the Multistix dipstick, so a real proteinuria could be presumed from the double analytical interference. CONCLUSIONS: This is the first report of analytical interference by quinolone and quinine derivatives in the PRM assay. Special attention to patients using these drugs is needed to minimize errors in the interpretation of urinary protein results.


Assuntos
Antibacterianos , Proteinúria/urina , Quinina , Quinolonas , Fitas Reagentes , Adulto , Estudos de Casos e Controles , Química Clínica/métodos , Reações Falso-Positivas , Feminino , Humanos , Masculino , Molibdênio/análise , Pirogalol/análogos & derivados , Adulto Jovem
9.
Ther Drug Monit ; 33(1): 128-31, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21079546

RESUMO

Spironolactone, which is metabolized to canrenone, is often used in combination with digoxin. Potassium canrenoate is a similar drug that is also metabolized to canrenone. As a result of reported interference of spironolactone, potassium canrenoate, and their common metabolite canrenone with digoxin immunoassays, we investigated potential interference of these compounds with two relatively new digoxin assays for application on ARCHITECT clinical chemistry platforms (cDig, particle-enhanced turbidimetric inhibition immunoassay) and ARCHITECT immunoassay platforms (iDig, chemiluminescent microparticle immunoassay), both from Abbott Diagnostics. When aliquots of drug-free serum pool were supplemented with various amounts of spironolactone, potassium canrenoate, and canrenone, no apparent digoxin concentration was observed using cDig assay on ARCHITECT c4000, c8000, and c16000 or iDig assay on i1000SR and i2000SR analyzers. In addition, we observed no false increase in serum digoxin value when aliquots of a digoxin pool were further supplemented with various amounts of spironolactone, potassium canrenoate, or canrenone. We conclude that both the cDig and iDig assays on the ARCHITECT analyzers are free from interferences by spironolactone, potassium canrenoate, and canrenone.


Assuntos
Antiarrítmicos/sangue , Ácido Canrenoico/sangue , Canrenona/sangue , Química Clínica/métodos , Digoxina/sangue , Imunoensaio/métodos , Espironolactona/sangue , Antiarrítmicos/metabolismo , Ácido Canrenoico/metabolismo , Canrenona/metabolismo , Reações Cruzadas , Digoxina/metabolismo , Antagonistas de Receptores de Mineralocorticoides/sangue , Espironolactona/metabolismo
10.
J Clin Lab Anal ; 24(6): 413-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21089173

RESUMO

Spironolactone, a potassium sparing diuretic metabolized to canrenone, is often used with digoxin to treat various conditions including congestive heart failure. Potassium canrenoate is a similar drug that is also metabolized to canrenone. Due to reported interference of spironolactone, potassium canrenoate, and their common metabolite canrenone with digoxin immunoassays, we investigated potential interference of these compounds with Dimension Vista Digoxin immunoassay using Flex reagent cartridge. Aliquots of a drug-free serum pool were supplemented with various amounts of spironolactone, potassium canrenoate, or canrenone and apparent digoxin values were measured using Dimension Vista digoxin assay, we observed none-detected value except when aliquots were supplemented with higher amounts of spironolactone or canrenone. Similarly, when aliquots of a serum digoxin pool (prepared by pooling specimens from patients receiving digoxin) where further supplemented with various amounts of spironolactone, potassium canrenoate, or canrenone, we observed moderately falsely elevated digoxin values only in specimens containing higher amounts of spironolactone or canrenone. We conclude that spironolactone and canrenone but not potassium canrenoate may cause modest interference with Dimension Vista digoxin assay but such interferences may not be clinically significant except with very high amounts of canrenone.


Assuntos
Ácido Canrenoico/química , Ácido Canrenoico/farmacologia , Canrenona/sangue , Canrenona/química , Cardiotônicos/farmacologia , Digoxina/sangue , Digoxina/química , Imunoensaio , Antagonistas de Receptores de Mineralocorticoides/sangue , Antagonistas de Receptores de Mineralocorticoides/química , Espironolactona/sangue , Espironolactona/química , Bioensaio , Ácido Canrenoico/sangue , Ácido Canrenoico/imunologia , Canrenona/imunologia , Cardiotônicos/sangue , Química Clínica/métodos , Reações Cruzadas , Digoxina/imunologia , Interações Medicamentosas , Monitoramento de Medicamentos , Humanos , Imunoensaio/métodos , Antagonistas de Receptores de Mineralocorticoides/imunologia , Antagonistas de Receptores de Mineralocorticoides/metabolismo , Concentração Osmolar , Kit de Reagentes para Diagnóstico , Espironolactona/imunologia , Espironolactona/metabolismo
12.
Lipids Health Dis ; 7: 19, 2008 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18489792

RESUMO

Dyslipidemia, and inflammatory markers: high-sensitivity C-reactive protein (hs-CRP), myeloperoxidase (MPO), lipoprotein associated phospholipase A2(Lp-PLA2), and lipid peroxides (LP) are insufficient to predict the onset, extent, and prognosis of CHD. Lipoxins (LXs), resolvins, and protectins are derived from omega-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and omega-6 arachidonic acid in the presence of aspirin; whereas nitrolipids are formed due to the interaction between polyunsaturated fatty acids and nitric oxide (NO). LXs, resolvins, protectins, and nitrolipids are endogenous anti-inflammatory lipid molecules that inhibit production of interleukin-6 (IL-6) and tumor necrosis factor- alpha (TNF-alpha), suppress free radical generation, enhance NO generation; and accelerate tissue repair. Thus, beneficial actions of EPA/DHA and aspirin in CHD could be attributed to the formation of LXs, resolvins, protectins, and nitrolipids and suggest that their plasma levels aid in the prediction and prognosis of CHD.


Assuntos
Biomarcadores/metabolismo , Doença das Coronárias/sangue , Doença das Coronárias/diagnóstico , Lipídeos/química , Proteína C-Reativa/biossíntese , Química Clínica/métodos , Ácidos Graxos/metabolismo , Humanos , Inflamação , Interleucina-6/biossíntese , Modelos Teóricos , Peroxidase/biossíntese , Fosfolipases A2/biossíntese , Prognóstico , Fatores de Risco , Fator de Necrose Tumoral alfa/biossíntese
13.
Int J Toxicol ; 26(5): 475-90, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17963134

RESUMO

Rats were fed diets containing 0%, 1%, 3%, or 5% mixed tocopheryl phosphates for 90 days. No abnormal clinical signs related to treatment appeared. Some statistically significant changes in hematology and clinical chemistry parameters appeared, but the majority were not dose dependent, occurred in only one sex or group, and/or remained within the historical control range for this strain of rat. A statistically significant apparent reduction in blood protein was observed in animals treated with the tocopheryl phosphates, but further investigation showed that the test substance interfered with the protein assay. Repeat analysis using a method unaffected by plasma test substance levels showed no difference in plasma proteins among all groups. Gross necropsy revealed no abnormalities; reduced relative heart and epididymal weights were observed, but were not dose dependent and were considered incidental. Histopathological changes occurred only in the mesenteric lymph node and small intestine. Foreign material in a crystal-like form appeared in macrophages in both organs, and increased in a dose-related fashion. In the lymph node, sinus histiocytosis increased with dose, but the severity was similar between the control and low-dose groups. Foreign-body granulomatous inflammation, associated with Maltese cross birefringence of the crystals was seen in the mid- and high-dose animals, but not the low-dose group. Similarly, the small intestine showed increasing amounts of foreign material and inflammation in the mid- and high-dose but not in the 1% diet. The 1% diet (equivalent to 587 and 643 mg mixed tocopheryl phosphates/kg body weight/day for male and female rats, respectively) was considered the no observed adverse effect level.


Assuntos
Testes de Toxicidade Crônica/métodos , alfa-Tocoferol/análogos & derivados , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Química Clínica/métodos , Cristalização , Dieta , Relação Dose-Resposta a Droga , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Epididimo/efeitos dos fármacos , Epididimo/patologia , Feminino , Coração/efeitos dos fármacos , Hematologia/métodos , Fígado/efeitos dos fármacos , Fígado/patologia , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Masculino , Mesentério/efeitos dos fármacos , Mesentério/patologia , Miocárdio/patologia , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Baço/efeitos dos fármacos , Baço/patologia , Urinálise/métodos , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/química , alfa-Tocoferol/toxicidade
14.
Ann Clin Lab Sci ; 36(4): 409-20, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17127727

RESUMO

Selenium poisoning in humans is reviewed from the perspective of the clinical laboratory. While evaluation of selenium poisoning is straightforward when the analytic results are markedly elevated and the patient is acutely symptomatic, distinguishing toxic from non-toxic elevations is a more frequent issue and more challenging. A significant problem is that selenium is determined as its total concentration in spite of the fact that different chemical forms of selenium have different toxic potentials. In the published reports reviewed herein, serum selenium concentrations span the following ranges: 400-30,000 micro g/L associated with acute toxicity, 500-1400 micro g/L associated with chronic toxicity, and <1400 micro g/L free of toxicity; the category is determined by signs and symptoms in the patient. Most reports that describe acute selenium poisoning involve ingestion of inorganic compounds such as selenious acid, found in gun-bluing agents, and fatalities that occur within the first day are associated with postmortem blood selenium levels >1400 micro g/L. Tissue selenium levels show a complex pattern and significant elevations in organs such as kidney are not always indicative of toxicity. As with many trace elements, measuring selenium concentrations in body fluids and tissues tends to be easier than understanding what the results mean.


Assuntos
Química Clínica/métodos , Selênio/intoxicação , Oligoelementos/intoxicação , Doença Aguda , Animais , Doença Crônica , Feminino , Humanos , Masculino , Valores de Referência , Selênio/sangue , Selênio/classificação , Oligoelementos/sangue , Oligoelementos/classificação
15.
J Lipid Res ; 47(11): 2515-24, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16943517

RESUMO

Isoprostanes (iPs) are prostaglandin-like molecules derived from autoxidation of polyunsaturated fatty acids (PUFAs). Urinary iP levels have been used as indices of in vivo lipid peroxidation. Thus far, it has only been possible to measure iPs derived from arachidonic acid in urine, because levels of iPs/neuroprostanes (nPs) derived from omega 3-PUFAs have been found to be below detection limits of available assays. Because of the interest in omega3-PUFA dietary supplementation, we developed specific methods to measure nPF4 alpha-VI and iPF3 alpha-VI [derived from 4,7,10,13,16,19-docosahexaenoic acid (DHA) and 5,8,11,14,17-eicosapentaenoic acid (EPA)] using a combination of chemical synthesis, gas chromatography/mass spectrometry (GC/MS), and liquid chromatography tandem mass spectrometry (LC/MS/MS). Although nPF4 alpha-VI was below the detection limit of the assay, we conclusively identified iPF3 alpha-VI in human urine by GC/MS and LC/MS/MS. The mean levels in 26 subjects were approximately 300 pg/mg creatinine. Our failure to detect nPF4 alpha-VI may have been due to its rapid metabolism by beta-oxidation to iPF3 alpha-VI, which we showed to occur in rat liver homogenates. In contrast, iPF3 alpha-VI is highly resistant to beta-oxidation in vitro. Thus iPF3 alpha-VI can be formed by two mechanisms: i) direct autoxidation of EPA, and ii) beta-oxidation of nPF4 alpha-VI, formed by autoxidation of DHA. This iP may therefore serve as an excellent marker for the combined in vivo peroxidation of EPA and DHA.


Assuntos
Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-3/urina , Isoprostanos/urina , Animais , Química Clínica/métodos , Ácidos Graxos/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fígado/metabolismo , Masculino , Modelos Químicos , Oxigênio/química , Oxigênio/metabolismo , Ratos , Fatores de Tempo
16.
Am J Clin Pathol ; 119(2): 298-303, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12580002

RESUMO

Asian and Siberian ginsengs contain glycosides with structural similarities to digoxin. We studied potential interference of ginseng in 5 digoxin immunoassays in 3 Asian (2 liquid extracts, 1 capsule) and 3 Siberian ginseng preparations (1 liquid extract, 2 capsules). With the fluorescence polarization immunoassay (FPIA), we observed apparent digoxin activity in 1 Asian liquid preparation and in the liquid extract and 1 capsule form of Siberian ginseng. In mice fed ginseng, we observed digoxin activities in the serum (Asian, 0.48-0.68 ng/mL [0.6-0.9 nmol/L]; Siberian, 0.20-0.47 ng/mL [0.3-0.6 nmol/L]), indicating that such interferences also occur in vivo. Serum pools prepared from samples from patients receiving digoxin and then supplemented with Asian or Siberian ginseng showed falsely increased digoxin values using the FPIA (e.g., for Asian ginseng, 1.54 ng/mL [2.0 nmol/L] vs control value, 1.10 ng/mL [1.4 nmol/L]) and falsely decreased values using the microparticle enzyme immunoassay (MEIA; 0.73 ng/mL [0.9 nmol/L] vs control value, 1.04 ng/mL [1.3 nmol/L]). Digoxin-like immunoreactive substances (DLISs) showed synergistic effects with ginsengs in interfering with the FPIA and MEIA for digoxin. No interference was observed with 3 other digoxin assays, even in the presence of elevated DLISs.


Assuntos
Química Clínica/métodos , Digoxina/química , Eleutherococcus/química , Imunoensaio/métodos , Panax/química , Animais , Digoxina/sangue , Digoxina/farmacocinética , Interações Medicamentosas , Monitoramento de Medicamentos , Eleutherococcus/imunologia , Eleutherococcus/metabolismo , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Camundongos , Panax/imunologia , Panax/metabolismo , Preparações de Plantas/farmacologia , Reprodutibilidade dos Testes
18.
Biol Trace Elem Res ; 79(2): 107-14, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11330516

RESUMO

This article describes a study in which four trace elements (Se, Mn, Cu, and Fe) were analyzed in the blood serum of the patients with colorectal cancer from the Moravian region of the Czech Republic. Atomic absorption spectrometry with graphite furnace atomization was used for analysis of selenium and manganese and with flame atomization for analysis of copper and iron. The observed serum concentrations in adenocarcinoma colorectal patients of selenium were significantly lower (41:8 +/- 11.6 microg/L) and those of manganese (16.3 +/- 4.5 microg/L) and iron (2.89 +/- 1.23 mg/L) were significantly higher as compared to the age-matched control group. Copper serum content (0.95 +/- 0.28 mg/L) did not significantly differ as compared to healthy population.


Assuntos
Neoplasias Colorretais/sangue , Cobre/sangue , Ferro/sangue , Manganês/sangue , Selênio/sangue , Adenocarcinoma/sangue , Antioxidantes/farmacologia , Calibragem , Estudos de Casos e Controles , Química Clínica/métodos , Humanos , Espectrofotometria Atômica , Temperatura
19.
Biol Trace Elem Res ; 79(2): 115-20, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11330517

RESUMO

Previous studies showed low selenium (Se) concentrations in Belgian children. Serum alpha-tocopherol, retinol, total cholesterol, high-density lipoprotein and low-density lipoprotein cholesterol, selenium (Se), and thiobarbituric acid-reactive substances were examined. In order to obtain further information on the Se status in Belgian children, Se, alpha-tocopherol, retinol, and lipid concentrations were examined and signs of peroxidative lipid damage were evaluated in a subgroup. The study was performed in 524 children (0-14 yr old) during vaccination campaigns. Three age groups were analyzed: 0-1, 1-4, and 4-14 yr. In 87 of them, where sufficient amounts of serum were available, analysis of thiobarbituric acid-reactive substances was done. Infants have high serum alpha-tocopherol concentrations: (23.2 micromol/L [median and interquartile range: 18.6-30.2]) and low Se concentrations (0.37 mol/L [0.27-0.47]). Se concentrations rise significantly during the first 4 yr (p < 0.0001) (Mann-Whitney U-test, tied p-values): 0.70 micromol/L (0.59-0.82); in the 4-14 yr olds, it was 0.75 micromol/L (0.67-0.86). These values remain low compared to results coming from other parts of the world. Alpha-tocopherol concentrations decrease significantly after infancy (p < 0.0001). The ratio alpha-tocopherol/total cholesterol is higher in infants. This is induced by the high vitamin E content of infant formulas. Signs of serum lipid peroxidation could not be detected by analysis of serum malondialdehyde concentrations. High alpha-tocopherol concentrations, as those observed in infant serum lipids, could be one of the protective mechanisms from the peroxidative lipid damages, sometimes observed in a low-Se status.


Assuntos
Selênio/sangue , Vitamina E/sangue , Adolescente , Fatores Etários , Bélgica , Química Clínica/métodos , Criança , Pré-Escolar , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
20.
Biol Trace Elem Res ; 79(2): 97-105, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11330526

RESUMO

In this work, we report on a relationship between urinary selenium and the development of cervical uterine cancer. A simple chemical method was developed to concentrate trace amounts of selenium from relatively large urine samples by use of small activated carbon filters. When these filters are irradiated with thermal neutrons, selenium can be determined either by 77mSe (t1/2 = 17.5 s) or 75Se (t1/2 = 120 d). In this article, we report the results for 82 urine samples from women with cervical uterine cancer in several stages of development and from healthy controls. These results show a statistically significant increase of selenium excretion in cancer patients as compared to controls. Urinary selenium excretion is highest for patients in the intermediate stages of the disease.


Assuntos
Selênio/urina , Neoplasias do Colo do Útero/urina , Adulto , Idoso , Estudos de Casos e Controles , Química Clínica/métodos , Feminino , Filtração , Humanos , Concentração de Íons de Hidrogênio , Pessoa de Meia-Idade , Modelos Estatísticos , Radioisótopos de Selênio/metabolismo , Fatores de Tempo , Distribuição Tecidual
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