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1.
Drug Res (Stuttg) ; 71(4): 193-198, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33184808

RESUMO

BACKGROUND: Lead is a hazardous heavy metal, which causes many problems in the human body. Unfortunately, recent reports showed that smugglers and opium sellers add lead to drugs during the production procedure in order to increase its weight and cost. PURPOSE: The aim of this study was development of a rapid and accurate method for measurement of blood lead levels (BLL) in the oral and inhaled opiate abuser people. METHODS: BLL in samples obtained from the oral and inhaled opium addicted patients referring to Sina Hospital in Tabriz, Iran, during 2017 was compared with healthy control group (N=15). The wet digestion method was used to prepare whole blood and Mercury Droplet Electrode Polarography (MDEP) method was utilized for measurement of the lead content of digested samples. RESULTS: Results showed that there were significant differences between the BLL of samples obtained from oral (17.12±74.61 µg/dL, p<0.0003) and inhaled (19.33±2.257 µg/dL, p<0.0001) opium addicted groups in comparison with healthy control group (4.669±0.3367 µg/dL). CONCLUSION: Based on the results of this study it was observed that BLL in opium addicted people needs to be measured as soon as possible. Furthermore, screening of blood lead concentrations in opium-addicted people with a rapid and accurate MDEP method is very necessary and important.


Assuntos
Contaminação de Medicamentos , Intoxicação por Chumbo/diagnóstico , Chumbo/sangue , Dependência de Ópio/sangue , Polarografia/instrumentação , Adolescente , Adulto , Idoso , Eletrodos , Estudos de Viabilidade , Feminino , Humanos , Irã (Geográfico) , Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/etiologia , Masculino , Mercúrio , Pessoa de Meia-Idade , Ópio/química , Dependência de Ópio/complicações , Sensibilidade e Especificidade , Adulto Jovem
2.
Braz J Med Biol Res ; 48(5): 408-14, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25714891

RESUMO

Liver fibrosis occurring as an outcome of non-alcoholic steatohepatitis (NASH) can precede the development of cirrhosis. We investigated the effects of sorafenib in preventing liver fibrosis in a rodent model of NASH. Adult Sprague-Dawley rats were fed a choline-deficient high-fat diet and exposed to diethylnitrosamine for 6 weeks. The NASH group (n=10) received vehicle and the sorafenib group (n=10) received 2.5 mg·kg(-1)·day(-1) by gavage. A control group (n=4) received only standard diet and vehicle. Following treatment, animals were sacrificed and liver tissue was collected for histologic examination, mRNA isolation, and analysis of mitochondrial function. Genes related to fibrosis (MMP9, TIMP1, TIMP2), oxidative stress (HSP60, HSP90, GST), and mitochondrial biogenesis (PGC1α) were evaluated by real-time quantitative polymerase chain reaction (RT-qPCR). Liver mitochondrial oxidation activity was measured by a polarographic method, and cytokines by enzyme-linked immunosorbent assay (ELISA). Sorafenib treatment restored mitochondrial function and reduced collagen deposition by nearly 63% compared to the NASH group. Sorafenib upregulated PGC1α and MMP9 and reduced TIMP1 and TIMP2 mRNA and IL-6 and IL-10 protein expression. There were no differences in HSP60, HSP90 and GST expression. Sorafenib modulated PGC1α expression, improved mitochondrial respiration and prevented collagen deposition. It may, therefore, be useful in the treatment of liver fibrosis in NASH.


Assuntos
Cirrose Hepática/tratamento farmacológico , Mitocôndrias Hepáticas/efeitos dos fármacos , Niacinamida/análogos & derivados , Hepatopatia Gordurosa não Alcoólica/complicações , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Chaperonina 60/análise , Chaperonina 60/genética , Dieta Hiperlipídica/métodos , Dietilnitrosamina , Modelos Animais de Doenças , Colágenos Fibrilares/efeitos dos fármacos , Glutationa Transferase/análise , Glutationa Transferase/genética , Proteínas de Choque Térmico HSP90/análise , Proteínas de Choque Térmico HSP90/genética , Interleucina-10/análise , Interleucina-10/genética , Interleucina-6/análise , Interleucina-6/genética , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Metaloproteinase 9 da Matriz/análise , Metaloproteinase 9 da Matriz/genética , Mitocôndrias Hepáticas/metabolismo , Niacinamida/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Polarografia , RNA Mensageiro/isolamento & purificação , Ratos Sprague-Dawley , Sorafenibe , Inibidor Tecidual de Metaloproteinase-1/análise , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-2/análise , Inibidor Tecidual de Metaloproteinase-2/genética , Fatores de Transcrição/análise , Fatores de Transcrição/genética
3.
Sci Total Environ ; 466-467: 898-905, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23973552

RESUMO

Seven deep-sea fish species were sampled in the Blanes Canyon area (NW Mediterranean) at a depth of 1200 m during winter. The concentrations of nine metals were determined in the liver of these species by ICP-MS. Furthermore, the metal detoxification potential was determined for each species by analysing the hepatic metallothionein (MT) content, relations between metals and the molar ratio between MT and/or selected metals. The potential effect of metal content on their physiology was assessed using general stress markers such as the enzyme activities of acetylcholinesterase (AChE) and lactate dehydrogenase (LDH) in muscle. Levels of metals in the seven Mediterranean deep-sea fish species studied were intermediate to equivalent species of fish either from Atlantic waters or hydrothermal vents. The metal detoxification potential varied among species depending on MT, selenium (Se) or zinc (Zn) as reliable mechanisms to handle potential metal toxicity. The role of Se was especially relevant when the liver content of mercury (Hg) was higher. AChE and LDH activities did seem to be affected by metal loads and thus the activities reported would correspond to baseline activities of the selected species.


Assuntos
Peixes/metabolismo , Fígado/metabolismo , Metalotioneína/metabolismo , Metais Pesados/farmacologia , Selênio/metabolismo , Poluentes Químicos da Água/farmacologia , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/metabolismo , Monitoramento Ambiental , Feminino , Proteínas de Peixes/metabolismo , Inativação Metabólica , L-Lactato Desidrogenase/metabolismo , Masculino , Espectrometria de Massas , Mar Mediterrâneo , Músculo Esquelético/enzimologia , Polarografia , Espanha
4.
Age (Dordr) ; 36(1): 167-81, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23852618

RESUMO

To clarify age-related histological and Zn content changes in nonhyperplastic adult prostate glands, a quantitative morphometric and energy-dispersive X-ray fluorescence analyses were performed. The prostates were obtained from autopsies of 63 subjects aged 21-70 years who died mainly from trauma. It was found that histologically normal prostate tissue undergoes substantial changes throughout aging. These changes are reflected in an increase of the percent volume of the glandular lumen for the third to fifth decades, reaching a maximum for the decade 41-50 years. Over the same period, the percent volume of the stroma remains steady, but the percent volume of epithelium decreases, approximately, linearly with age. The percent volume of glandular lumen (reflects the volume of prostatic fluid) in the prostate gland of men aged 41 to 50 years is 1.5-fold higher than that in men aged 21 to 30 years, but the epithelium/lumen (prostatic fluid) ratio is approximately twofold lower. This suggests that accumulation of the prostatic fluid develops from 30 to 50 years of age. This accumulation of the prostatic fluid results in an increase of the Zn mass fraction in the prostate. In turn, when the intraprostatic Zn level exceeds a certain level by the end of the fifth decade, it begins to work as a trigger for different factors, all of which increase the proliferation of stromal cells. Deductions from these results allow possible partial explanations of both relevant prostatic aging mechanisms and the effects of dietary interventions using supplementary Zn.


Assuntos
Próstata/química , Zinco/análise , Adulto , Fatores Etários , Idoso , Autopsia , Humanos , Masculino , Pessoa de Meia-Idade , Polarografia , Espectrometria por Raios X , Espectrofotometria Atômica
5.
J Agric Food Chem ; 60(38): 9573-80, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22950743

RESUMO

Hydrogen peroxide scavenging (HPS) activity of unfermented (green, yellow, and white), partially fermented (oolong), and completely fermented (black) tea ( Camellia sinensis ), maté ( Ilex paraguariensis ), and various herbal infusions, as well as individual compounds (flavan-3-ols, flavonols, cinnamic and benzoic acids, and methylxanthines), was assessed by recently developed direct current (DC) polarographic assay. Correlations of tea and herbal infusion HPS activity with total phenolic content determined using the Folin-Ciocalteu assay (FC-GAE) (0.81 and 0.93), ferric reducing/antioxidant power (FRAP) (0.97 and 0.92), 1,1-diphenyl-2-picrylhydrazyl (DPPH) (0.77 and 0.80), and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) scavenging (0.86 and 0.86) were statistically significant. Correlations between relative antioxidant capacity index (RACI), calculated by assigning all applied assays equal weight, and HPS (0.98), FRAP (0.97), ABTS (0.89), and DPPH (0.89) confirmed DC polarographic assay reliability when applied individually. Correlation analysis, ANOVA, and Levene and Tukey's HSD tests unequivocally confirmed this reliable, rapid, and low-cost assay validity, clearly demonstrating its advantages over spectrophotometric assays applied.


Assuntos
Antioxidantes/análise , Bebidas/análise , Polarografia/métodos , Chá/química , Ácido Benzoico/análise , Benzotiazóis/química , Compostos de Bifenilo/química , Camellia sinensis/química , Cinamatos/análise , Flavonóis/análise , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/química , Peróxido de Hidrogênio/análise , Ilex paraguariensis/química , Fenóis/análise , Picratos/química , Reprodutibilidade dos Testes , Ácidos Sulfônicos/química , Xantinas/análise , Xantinas/química
6.
J Food Sci ; 77(6): C574-82, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22582811

RESUMO

UNLABELLED: Gelatinized water yam starch was subjected to hydrothermal treatment (25, 30, and 35% moisture content for 1, 8, 16, and 24 h at 100 °C) and characterized by X-ray diffractometry, solid-state ¹³C cross-polarization and magic-angle spinning nuclear magnetic resonance, differential scanning calorimetry, and digestibility analysis. The slowly digestible starch (SDS) content of the starch treated at 30% moisture content for 24 h reached 49.1%, 31.9% higher than that of the control starch. The B-type pattern of native starch was re-crystallized to the A-type by hydrothermal treatment. The SDS content showed negative correlations with T(o), T(p), T(c), and T(r), but showed a positive correlation with melting enthalpy. Furthermore, SDS was positively correlated with hydrothermal reaction time, moisture content, relative crystallinity, and the double-helix proportion. The structural changes in hydrothermally treated water yam starches resulted in the enhancement of SDS. PRACTICAL APPLICATION: The hydrothermally treated water yam starch could be used as a food ingredient for slow-energy supply or dietary fiber.


Assuntos
Fibras na Dieta/análise , Digestão , Dioscorea/química , Manipulação de Alimentos/métodos , Tubérculos/química , Amido/química , Água/análise , Varredura Diferencial de Calorimetria , Configuração de Carboidratos , Fenômenos Químicos , Fibras na Dieta/metabolismo , Alimentos Fortificados/análise , Géis , Temperatura Alta , Ressonância Magnética Nuclear Biomolecular , Transição de Fase , Polarografia , República da Coreia , Amido/isolamento & purificação , Amido/metabolismo , Fatores de Tempo , Vietnã , Difração de Raios X
7.
Phytochem Anal ; 22(3): 189-98, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21341339

RESUMO

INTRODUCTION: It is estimated that about 70-80% of the world's population relies on non-conventional medicine, mainly of herbal origin. However, owing to the nature and sources of herbal medicines, they are sometimes contaminated with toxic heavy metals such as lead, arsenic, mercury and cadmium, which impose serious health risks to consumers. It is critical to analyse source materials for heavy metals in order to ensure that their concentrations meet the related standards or regulations limiting their concentrations in herbal medicines. In this review, different analytical methods for analysis of heavy metals in herbal medicines are discussed. OBJECTIVE: To provide a comprehensive review of the current state of the art in analytical methods used to detect heavy metals in herbal medicines. METHODOLOGY: We systematically searched and reviewed the research articles regarding analytical methods for heavy metals in herbal medicine from various databases, such as Medline/PubMed, ScienceDirect, SciFinder, Google Scholar, EBSCO, Gale InfoTrac, Ingenta, Ovid, ProQuest and ISI Web of Knowledge. RESULTS: In this review, we discuss in detail several commonly used and sensitive analytical techniques, including atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry or mass spectrometry, X-ray fluorescence spectrometry, high-performance liquid chromatography, differential pulse polarography, neutron activation analysis and anodic stripping voltammetry. We also provide some application examples of these analytical techniques for heavy metals in herbal medicines.


Assuntos
Técnicas de Química Analítica/métodos , Metais Pesados/análise , Preparações de Plantas/química , Plantas Medicinais/química , Arsênio/análise , Cádmio/análise , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Medicamentos , Técnicas Eletroquímicas/métodos , Humanos , Chumbo/análise , Espectrometria de Massas/métodos , Mercúrio/análise , Análise de Ativação de Nêutrons/métodos , Polarografia/métodos , Espectrometria por Raios X/métodos , Espectrofotometria Atômica/métodos
8.
J Appl Physiol (1985) ; 109(3): 804-19, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20558753

RESUMO

Breathing hyperbaric oxygen (HBO) is common practice in hyperbaric and diving medicine. The benefits of breathing HBO, however, are limited by the risk of central nervous system O2 toxicity, which presents as seizures. We tested the hypothesis that excitability increases in CA1 neurons of the rat hippocampal slice (400 microm) over a continuum of hyperoxia that spans normobaric and hyperbaric pressures. Amplitude changes of the orthodromic population spike were used to assess neuronal O2 sensitivity before, during, and following exposure to 0, 0.6, 0.95 (control), 2.84, and 4.54 atmospheres absolute (ATA) O2. Polarographic O2 electrodes were used to measure tissue slice PO2 (PtO2). In 0.95 ATA O2, core PtO2 at 200 microm deep was 115±16 Torr (mean±SE). Increasing O2 to 2.84 and 4.54 ATA increased core PtO2 to 1,222±77 and 2,037±157 Torr, respectively. HBO increased the orthodromic population spike amplitude and usually induced hyperexcitability (i.e., secondary population spikes) and, in addition, a long-lasting potentiation of the orthodromic population spike that we have termed "oxygen-induced potentiation" (OxIP). Exposure to 0.60 ATA O2 and hypoxia (0.00 ATA) decreased core PtO2 to 84±6 and 20±4 Torr, respectively, and abolished the orthodromic response. Reoxygenation from 0.0 or 0.6 ATA O2, however, usually produced a response similar to that of HBO: hyperexcitability and activation of OxIP. We conclude that CA1 neurons exhibit increased excitability and neural plasticity over a broad range of PtO2, which can be activated by a single, hyperoxic stimulus. We postulate that transient acute hyperoxia stimulus, whether caused by breathing HBO or reoxygenation following hypoxia (e.g., disordered breathing), is a powerful stimulant for orthodromic activity and neural plasticity in the CA1 hippocampus.


Assuntos
Região CA1 Hipocampal/metabolismo , Oxigenoterapia Hiperbárica , Hiperóxia/metabolismo , Plasticidade Neuronal , Neurônios/metabolismo , Oxigênio/metabolismo , Potenciais de Ação , Animais , Região CA1 Hipocampal/fisiopatologia , Hiperóxia/fisiopatologia , Técnicas In Vitro , Eletrodos Seletivos de Íons , Masculino , Polarografia/instrumentação , Pressão , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
9.
J Agric Food Chem ; 58(2): 744-51, 2010 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-20014862

RESUMO

A novel antioxidative assay based on direct current polarography has been developed. Quantification of antioxidative (AO) activity has been based on a decrease of hydrogen peroxide anodic current in the presence of antioxidants. An efficient experimental procedure, without any special pretreatment of analyzed samples, has been applied. Antioxidative activity of different kinds of commercial beers (dark, blond, and alcohol-free), some small-scale made special beers with medicinal herbs and mushroom extracts, extracts themselves, as well as individual phenolic components present in beer has been measured. In addition, changes of AO activity during the full-scale industrial process of beer production have been monitored. A strong correlation between results obtained and total phenolics content has been observed. The assay can be recommended for application in brewing industry, either to survey a process with the aim to optimize relevant technological factors or to analyze quality of final product.


Assuntos
Antioxidantes/análise , Cerveja/análise , Manipulação de Alimentos , Polarografia/métodos , Fermentação
10.
Z Naturforsch C J Biosci ; 64(5-6): 350-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19678537

RESUMO

A hitherto unidentified endophytic strain of the genus Chaetomium, isolated from the medicinal plant Otanthus maritimus, yielded a new tetrahydrofuran derivative, aureonitolic acid (1), along with 5 known natural products, 2-6. The structure of 1 was determined by extensive spectroscopic analysis and comparison with reported data. Extracts of the fungus, grown either in liquid culture or on solid rice media, exhibited considerable cytotoxic activity when tested in vitro against L5178Y mouse lymphoma cells. Compounds 2 and 6 showed significant growth inhibition against L5178Y cells with EC50 values of 7.0 and 2.7 microg/mL, respectively, whereas 1 was inactive.


Assuntos
Asteraceae/microbiologia , Chaetomium/química , Furanos/isolamento & purificação , Furanos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Chaetomium/isolamento & purificação , Furanos/química , Leucemia L5178/tratamento farmacológico , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Camundongos , Plantas Medicinais/microbiologia , Polarografia
11.
Ann Chim ; 96(11-12): 647-56, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17217169

RESUMO

This paper deals with determination of selenium and analysis of its speciation in some Italian mineral waters. Selenium was determined by differential pulse cathodic stripping voltammetry (DPCSV) even if square wave cathodic stripping voltammetry (SWCSV) was also taken into consideration. The selenium determined in the mineral waters here investigated is not over 600 ng L(-1); in three samples, it was found below the detection limit. Analysis of speciation revealed that Se(VI) is the highly prevailing form present: only two of the examined samples revealed a detectable amount (few ng L(-1)) of Se(IV). DPCSV made possible to detect, in two of the samples, the presence of a specie(s) able to interact with Se(IV). The apparent interaction constant for the adduct formation was evaluated and the species concentration determined. However, the nature of such compound(s) remains unknown.


Assuntos
Bebidas/análise , Selênio/análise , Água/análise , Itália , Polarografia
12.
J Pharm Pharmacol ; 56(6): 813-8, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15231048

RESUMO

Although the number of prescriptions for psychotropic drugs has decreased in recent years, prescriptions for antidepressants are still increasing (Fritze 2002). Hypericum perforatum (St John's wort) is the main psychotherapeutic herbal medicinal product used for treatment of mild-to-moderate depression. The lipophilic constituent hyperforin (2-5% of the extract) demonstrated, similarly to chemical antidepressants, a significant effect on the synaptosomal uptake inhibition of several neurotransmitters in in-vitro assays. In Germany, St John's wort products are distributed via two different markets: products that are pharmacy restricted are only allowed to be distributed in pharmacies; traditionally used products, which do not claim to have a curative character, are allowed to be sold in supermarkets. Depending on the market wherein a St John's wort product is offered, it needs to fulfill the legal requirements regarding pharmaceutical quality, safety and efficacy. Our goal was to compare the quality of St John's wort products distributed in pharmacies with that of those available from supermarkets. Therefore, the quantity of the pharmaceutical active ingredients (the phloroglucinol derivate hyperforin, the flavonoids rutin, hyperoside, isoquercitrin, quercitrin and the biflavonoid biapigenin) was determined by high-performance liquid chromatography (HPLC). The naphthodianthrones hypericines and pseudohypericines were quantified by differential pulse polarography (DPP). The efficacy of the products was investigated by measuring their activity to inhibit serotonin (5-HT) uptake in-vitro using a radio ligand uptake assay. It could be demonstrated that the products were different not only in the concentration of pharmaceutically relevant ingredients but also in showing individual IC50 values (concentration producing half-maximal inhibition) in the serotonin reuptake assay (IC50 values between 3.07 and 17.9 microg extract mL(-1)). The results of our study confirm the assumption that the potency of St John's wort products in inhibiting the uptake of serotonin depends on the amount of hyperforin in their dosage forms. St John's wort products having greater hyperforin content and potency on synaptosomal serotonin uptake inhibition are restricted to be sold only in pharmacies.


Assuntos
Hypericum/química , Inibidores Seletivos de Recaptação de Serotonina/química , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Sinaptossomos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Controle de Medicamentos e Entorpecentes , Lobo Frontal/ultraestrutura , Alemanha , Técnicas In Vitro , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/normas , Polarografia , Inibidores Seletivos de Recaptação de Serotonina/normas
13.
Physiol Res ; 52(6): 781-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14640901

RESUMO

Inherited disturbances of the mitochondrial energy generating system represent a heterogeneous group of disorders associated with a broad spectrum of metabolic abnormalities and clinical symptoms. We used the polarographic and spectrophotometric method for detection of mitochondrial disorders, because these two techniques provide a different insight into mitochondrial function. In six patients suspected of mitochondrial disease we found defects of complex I (two patients), complex III (one patient), complex IV (two patients) and a combination of defect of complex III and IV (one patient). Citrate synthase activity, used as the reference enzyme, was not changed. A comparison of the two methods showed several differences in evaluation of mitochondrial enzymes activity due to the fact that both methods used different conditions for enzyme activity measurements. In contrast to oxygen consumption measurements, where the function of the whole-integrated respiratory chain is characterized, spectrophotometric measurements characterize activities of isolated complexes in disintegrated membranes. However, it may be concluded from our experiments that both methods provide useful and complementary data about mitochondrial energetic functions. Whereas spectrophotometric data are suitable for evaluation of maximal enzyme activities of mitochondrial enzyme complexes, polarographic data provide better information about enzyme activities in cells with mitochondrial defects under in situ conditions.


Assuntos
Doenças Genéticas Inatas/metabolismo , Mitocôndrias Musculares/enzimologia , Doenças Mitocondriais/metabolismo , Músculo Esquelético/enzimologia , Polarografia/métodos , Adolescente , Adulto , Permeabilidade da Membrana Celular/efeitos dos fármacos , Criança , Pré-Escolar , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Complexo II de Transporte de Elétrons/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Doenças Genéticas Inatas/fisiopatologia , Humanos , Lactente , Síndrome de Kearns-Sayre/metabolismo , Síndrome de Kearns-Sayre/fisiopatologia , Síndrome MELAS/genética , Síndrome MELAS/metabolismo , Síndrome MELAS/fisiopatologia , Mitocôndrias Musculares/metabolismo , Doenças Mitocondriais/fisiopatologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Espectrofotometria
14.
Phytochem Anal ; 14(4): 224-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12892418

RESUMO

A reliable and simple differential pulse polarographic method is described for the determination of thymoquinone in black seed oil. The polarographic behaviour of thymoquinone was examined in various buffer systems over the pH range 5.0-10.0. Thymoquinone is reduced in a single, reversible peak at the dropping mercury electrode. The differential pulse polarogram showed a distinct peak in Sörensen buffer:methanol (3:7, v/v; pH 8.5) at a peak potential of -0.095 V (vs. silver/silver chloride electrode), and a plot of peak height against concentration was found to be linear over the range 0.2-15.0 microg/mL (R = 0.9998). The limit of detection was calculated to be 0.054 microg/mL. The polarographic method has been applied to determine thymoquinone in two black seed oil preparations available on the Austrian pharmaceutical market.


Assuntos
Benzoquinonas/análise , Nigella sativa/química , Óleos de Plantas/química , Polarografia/métodos , Sementes/química , Concentração de Íons de Hidrogênio , Modelos Biológicos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Óleos de Plantas/isolamento & purificação
15.
Biomed Sci Instrum ; 39: 554-60, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12724951

RESUMO

It was recently shown that antibodies catalyze a reaction between water and ultraviolet light (UV) creating singlet oxygen and ultimately H2O2. Although the in vivo relevance of these antibody reactions is unclear, it is interesting that among a wide variety of non-antibody proteins tested, the T cell receptor is the only protein with similar capabilities. In clinical settings UV is believed to exert therapeutic effects by eliminating inflammatory epidermal T cells and we hypothesized that UV-triggered H2O2 production is involved in this process. To test the hypothesis we developed tools to study production of H2O2 by T cell receptors with the long-term goal of understanding, and improving, UV phototherapy. Here, we report the development of an inexpensive, real time H2O2 monitoring system having broad applicability. The detector is a Clark oxygen electrode (Pt, Ag/AgCl) modified to detect UV-driven H2O2 production. Modifications include painting the electrode black to minimize UV effects on the Ag/AgCl electrode and the use of hydrophilic, large pore Gelnots electrode membranes. Electrode current was converted to voltage and then amplified and recorded using a digital multimeter coupled to a PC. A reaction vessel with a quartz window was developed to maintain constant temperature while permitting UV irradiation of the samples. The sensitivity and specificity of the system and its use in cell-free and cell-based assays will be presented. In a cellfree system, production of H2O2 by CD3 antibodies was confirmed using our real time H2O2 monitoring method. Additionally we report the finding that splenocytes and Jurkat T cells also produce H2O2 when exposed to UV light.


Assuntos
Anticorpos Catalíticos/metabolismo , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/metabolismo , Polarografia/instrumentação , Água/metabolismo , Animais , Anticorpos/análise , Anticorpos/metabolismo , Anticorpos Catalíticos/química , Anticorpos Catalíticos/efeitos da radiação , Complexo CD3/metabolismo , Complexo CD3/efeitos da radiação , Calibragem , Sistema Livre de Células/metabolismo , Eletrodos , Desenho de Equipamento , Humanos , Células Jurkat/metabolismo , Células Jurkat/efeitos da radiação , Masculino , Membranas Artificiais , Oxirredução , Ratos , Ratos Sprague-Dawley , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/efeitos da radiação , Sensibilidade e Especificidade , Baço/química , Baço/metabolismo , Baço/efeitos da radiação , Temperatura , Raios Ultravioleta , Água/química
16.
Chem Pharm Bull (Tokyo) ; 51(5): 595-8, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12736464

RESUMO

According to the traditional usage of the plant for antiinflammation and analgesia, Leucas aspera was tested for its prostaglandin (PG) inhibitory and antioxidant activities. The extract showed both activities, i.e., inhibition at 3 x 10(-4) g/ml against PGE(1)- and PGE(2)-induced contractions in guinea pig ileum and a 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect. The separation guided by the activities in these dual assay methods provided eight lignans and four flavonoids, LA-1- -12, among which LA-1- -7 and LA-10- -12 were identified as nectandrin B, meso-dihydroguaiaretic acid, macelignan, acacetin, apigenin 7-O-[6"-O-(p-coumaroyl)-beta-D-glucoside], chrysoeriol, apigenin, erythro-2-(4-allyl-2, 6-dimethoxyphenoxy)-1-(4-hydroxy-3-methoxyphenyl)propan-1-ol, myristargenol B, and machilin C, respectively. LA-8 was determined to be (-)-chicanine, the new antipode of the (+) compound, by spectroscopic methods including CD and ORD. Chiral-HPLC analysis of LA-9 showed that it was a mixture of two enantiomers, (7R, 8R)- and (7S, 8S)-licarin A. All of these components were first isolated from L. aspera. PG inhibition was observed in LA-1, LA-2, and LA-5, and antioxidant activity in LA-1- -3 and LA-8- -12.


Assuntos
Antioxidantes/química , Plantas Medicinais/química , Antagonistas de Prostaglandina/química , Alprostadil/antagonistas & inibidores , Alprostadil/farmacologia , Animais , Antioxidantes/isolamento & purificação , Bangladesh , Compostos de Bifenilo , Cromatografia em Camada Fina , Dicroísmo Circular , Dinoprostona/antagonistas & inibidores , Dinoprostona/farmacologia , Cobaias , Íleo/efeitos dos fármacos , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Polarografia , Antagonistas de Prostaglandina/isolamento & purificação
18.
East Mediterr Health J ; 9(1-2): 28-36, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15562730

RESUMO

Trace element concentrations in khat were investigated as they can disturb trace element levels in the body. Cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) levels in khat and 6 leafy vegetables commonly consumed in the Republic of Yemen were determined by differential pulse anodic stripping voltammetry after wet digestion of the organic matter. Khat had significantly higher concentrations of Cu and Zn than did the leafy vegetables, but similar amounts of Cd and Pb. The average daily intake of khat consumers of Cd, Pb, Cu and Zn from khat only was estimated to be 2.0-10.2 microg/day, 23.6-118.0 microg/day, 530-2654 microg/day and 662-3311 microg/day respectively. Although high, these values were within Food and Agriculture Organization/World Health Organization tolerance limits.


Assuntos
Cádmio/análise , Catha/química , Cobre/análise , Chumbo/análise , Preparações de Plantas/química , Polarografia/métodos , Zinco/análise , Brassica/química , Brassicaceae/química , Calibragem , Monitoramento Ambiental/métodos , Manipulação de Alimentos/métodos , Humanos , Lactuca/química , Política Nutricional , Cebolas/química , Petroselinum/química , Polarografia/instrumentação , Polarografia/normas , Raphanus/química , Sensibilidade e Especificidade , Verduras/química , Iêmen
19.
J Pharmacol Exp Ther ; 304(1): 277-83, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12490602

RESUMO

Amiodarone (AM) is an efficacious antidysrhythmic agent that can cause numerous adverse effects, including potentially life-threatening pulmonary fibrosis. The current study was undertaken to investigate potential protective mechanisms of vitamin E against AM-induced pulmonary toxicity (AIPT) in the hamster. Three weeks after intratracheal administration of AM (1.83 micromol), increased pulmonary hydroxyproline content and histological damage were observed, indicative of fibrosis. These effects were preceded by increased pulmonary levels of transforming growth factor (TGF)-beta1 mRNA at 1 week post-AM, which remained elevated 3 weeks post-AM. Dietary supplementation with vitamin E resulted in rapid pulmonary accumulation of the vitamin, and prevention of AM-induced increases in TGF-beta1, hydroxyproline, and histological damage. Although dietary supplementation also markedly elevated lung mitochondrial vitamin E content, it did not attenuate AM-induced inhibition of mitochondrial respiration or disruption of mitochondrial membrane potential in vitro, or lung mitochondrial respiratory inhibition resulting from in vivo AM administration. These results suggest that vitamin E reduces the extent of pulmonary damage after AM administration via down-regulating TGF-beta1 overexpression but that it does not modify AM-induced mitochondrial dysfunction, a potential initiating event in AIPT.


Assuntos
Amiodarona/análogos & derivados , Amiodarona/antagonistas & inibidores , Amiodarona/toxicidade , Antiarrítmicos/antagonistas & inibidores , Antiarrítmicos/toxicidade , Antioxidantes/farmacologia , Expressão Gênica/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Fibrose Pulmonar/prevenção & controle , Fator de Crescimento Transformador beta/biossíntese , Vitamina E/farmacologia , Animais , Cricetinae , Sondas de DNA , Dieta , Hidroxiprolina/metabolismo , Hibridização In Situ , Pulmão/química , Pulmão/patologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Mesocricetus , Consumo de Oxigênio , Polarografia , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , RNA Mensageiro/biossíntese , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta1
20.
Ars pharm ; 44(3): 271-279, 2003. tab, graf
Artigo em En | IBECS | ID: ibc-25372

RESUMO

El objeto del estudio es la selección de las condiciones adecuadas para la preparación de la muestra y las instrumentales para la determinación de ácido ascórbico en fórmulas de base láctea para lactantes por polarografía diferencial de impulsos. La bondad del método se estima determinando los parámetros analíticos. Se obtiene un límite de detección equivalente a 15 mg de ácido ascórbico por 100 g de fórmula, una respuesta lineal en el intervalo de 15 a 550 mg de ácido ascórbico por 100g de muestra, una precisión interdía del 4,33 por ciento y una recuperación del 95 por ciento, valores que indican la bondad del método para el fin propuesto (AU)


Assuntos
Lactente , Humanos , Ácido Ascórbico/análise , Alimentos Formulados/análise , Polarografia/métodos , Polarografia/normas , Fenômenos Fisiológicos da Nutrição do Lactente
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