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1.
Foods ; 12(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37048333

RESUMO

Morphine and codeine are the two principal opiates found in the opium poppy (Papaver somniferum L.) and are therapeutically used for pain management. Poppy seeds with low opiates are primarily used for culinary purposes due to their nutritional and sensory attributes. Intentional adulteration of poppy seeds is common, often combined with immature, less expensive, exhausted, or substituted with morphologically similar seeds, viz., amaranth, quinoa, and sesame. For a safer food supply chain, preventive measures must be implemented to mitigate contamination or adulteration. Moreover, the simultaneous analysis of P. somniferum and its adulterants is largely unknown. Pre- and post-processing further complicate the alkaloid content and may pose a significant health hazard. To address these issues, two independent methods were investigated with eight botanically verified and fifteen commercial samples. Microscopical features were established for the authenticity of raw poppy seeds. Morphine, codeine, and thebaine quantities ranged from 0.8-223, 0.2-386, and 0.1-176 mg/kg, respectively, using LC-QToF. In most cases, conventional opiates have a higher content than papaverine and noscapine. The analytical methodology provided a chemical profile of 47 compounds that can be effectively applied to distinguish poppy seeds from their adulterants and may serve as an effective tool to combat ongoing adulteration.

2.
Molecules ; 25(6)2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32213805

RESUMO

Avocado oil is prized for its high nutritional value due to the substantial amounts of triglycerides (TGs) and unsaturated fatty acids (FAs) present. While avocado oil is traditionally extracted from mature fruit flesh, alternative sources such as avocado seed oil have recently increased in popularity. Unfortunately, sufficient evidence is not available to support the claimed health benefit and safe use of such oils. To address potential quality issues and identify possible adulteration, authenticated avocado oils extracted from the fruit peel, pulp and seed by supercritical fluid extraction (SFE), as well as commercial avocado pulp and seed oils sold in US market were analyzed for TGs and FAs in the present study. Characterization and quantification of TGs were conducted using UHPLC/ESI-MS. Thirteen TGs containing saturated and unsaturated fatty acids in avocado oils were unambiguously identified. Compared to traditional analytical methods, which are based only on the relative areas of chromatographic peaks neglecting the differences in the relative response of individual TG, our method improved the quantification of TGs by using the reference standards whenever possible or the reference standards with the same equivalent carbon number (ECN). To verify the precision and accuracy of the UHPLC/ESI-MS method, the hydrolysis and transesterification products of avocado oil were analyzed for fatty acid methyl esters using a GC/MS method. The concentrations of individual FA were calculated, and the results agreed with the UHPLC/ESI-MS method. Although chemical profiles of avocado oils from pulp and peel are very similar, a significant difference was observed for the seed oil. Principal component analysis (PCA) based on TG and FA compositional data allowed correct identification of individual avocado oil and detection of possible adulteration.


Assuntos
Persea/química , Óleos de Plantas/química , Cromatografia Líquida de Alta Pressão , Ácidos Graxos Insaturados/análise , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas por Ionização por Electrospray , Triglicerídeos/análise
3.
Infect Dis Poverty ; 9(1): 14, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32019611

RESUMO

BACKGROUND: Despite the availability of free tuberculosis (TB) diagnosis and treatment, TB care still generates substantial costs that push people into poverty. We investigated out-of-pocket (OOP) payments for TB care and assessed the resulting economic burden and economic consequences for those with varying levels of household income in eastern China. METHODS: A cross-sectional study was conducted among TB patients in the national TB programme networks in eastern China. TB-related direct OOP costs, time loss, and coping strategies were investigated across households in different economic strata. Analysis of Variance was used to examine the differences in various costs, and Kruskal-Wallis tests were used to compare the difference in total costs as a percentage of annual household income. RESULTS: Among 435 patients, the mean OOP total costs of TB care were USD 2389.5. In the lower-income quartile, OOP payments were lower, but costs as a percentage of reported annual household income were higher. Medical costs and costs prior to treatment accounted for 66.4 and 48.9% of the total costs, respectively. The lower the household income was, the higher the proportion of medical costs to total costs before TB treatment, but the lower the proportion of medical costs patients spent in the intensive phase. TB care caused 25.8% of TB-affected households to fall below the poverty line and caused the poverty gap (PG) to increase by United States Dollar (USD) 145.6. Patients in the poorest households had the highest poverty headcount ratio (70.2%) and PG (USD 236.1), but those in moderately poor households had the largest increase in the poverty headcount ratio (36.2%) and PG (USD 177.8) due to TB care. Patients from poor households were more likely to borrow money to cope with the costs of TB care; however, there were fewer social consequences, except for food insecurity, in poor households. CONCLUSIONS: Medical and pretreatment costs lead to high costs of TB care, especially among patients from the poorest households. It is necessary to train health system staff in general hospitals to promptly identify and refer TB patients. Pro-poor programmes are also needed to protect TB patients from the medical poverty trap.


Assuntos
Gastos em Saúde , Seguro Saúde/economia , Pobreza , Tuberculose/economia , Adulto , China , Feminino , Financiamento Pessoal , Custos de Cuidados de Saúde , Humanos , Renda , Masculino , Fatores Socioeconômicos , Fatores de Tempo
4.
J Pharm Sci ; 108(12): 3923-3931, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31562869

RESUMO

Because voriconazole metabolism is highly influenced by liver function, the dose regimen of voriconazole should be carefully assessed in patients with liver cirrhosis. We aimed to identify significant factors associated with plasma concentrations. Blood samples were collected from patients with liver cirrhosis who received voriconazole, and voriconazole concentrations were determined. One-compartment model with first-order absorption and elimination appropriately characterized the in vivo process of voriconazole. The typical population value of voriconazole clearance (CL) was 1.45 L/h and the volume of distribution (V) was 132.12 L. The covariate analysis identified that CYP2C19 gene phenotype and Child-Pugh classification were strongly associated with CL and body weight had a significant influence on V. The results of the Monte Carlo simulation suggested that CYP2C19 gene phenotype was a critical factor for determining voriconazole dosage in patients with liver cirrhosis. The extensive metabolizer patients with Aspergillus fumigatus infections could be treated effectively with a recommended dose of 75 mg twice daily in mild to moderate liver cirrhosis and 100 mg once daily in moderate severe liver cirrhosis. However, the recommended dosage for Candida albicans infections patients was not achieved in present study.


Assuntos
Antifúngicos/farmacocinética , Cirrose Hepática/metabolismo , Voriconazol/farmacocinética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Citocromo P-450 CYP2C19/metabolismo , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Método de Monte Carlo , Fenótipo , Estudos Retrospectivos , Adulto Jovem
5.
J Appl Toxicol ; 39(2): 398-408, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30325045

RESUMO

Twenty-four pure fragrance ingredients of concern as potential skin sensitizers were previously subjected to degradation studies and evaluated using the high throughput with dansyl cysteamine (HTS-DCYA) method. The experimental results showed that two-thirds of the 24 fragrance ingredients underwent chemical degradation. In some cases, such degradation was accompanied by an increase in thio-reactivity. These results prompted us to investigate the reactivity of the same ingredients using the direct peptide reactivity assay (DPRA). In the present work, the 24 chemicals were subjected to forced degradation for 150 days, and evaluated with both DPRA and HTS-DCYA methods. At the end of the study, four and eight compounds remained non-reactive in the DPRA and DCYA assay, respectively. Coumarin, benzyl salicylate, benzyl cinnamate and hexyl cinnamal were found unreactive in both assays, while cinnamal, cinnamyl alcohol, hydroxycitronellal and lilial were found negative in the DCYA but positive in the DPRA method. The incongruity in reactivity of these four compounds was attributed to a possible role of pro-oxidants formed upon degradation, resulting in depletion of peptide without formation of apparent covalent adducts with the test chemical. To validate this hypothesis, the effect of hydrogen peroxide as model pro-oxidant on both lysine- and cysteine-heptapeptide depletion in the DPRA method was thus investigated. The obtained results showed little effect of oxidative conditions on lysine depletion, while cysteine depletion was significantly affected by concentrations above 1.1 mg/L of hydrogen peroxide. Overall, both in chemico methods confirmed chemical instability should be considered when assessing the skin sensitization potential of (un)known chemicals with alternative methods.


Assuntos
Alternativas aos Testes com Animais/métodos , Cosméticos/toxicidade , Odorantes , Peptídeos/química , Pele/efeitos dos fármacos , Cisteamina/química , Compostos de Dansil/química , Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/metabolismo , Humanos , Oxirredução
6.
Shanghai Kou Qiang Yi Xue ; 27(4): 382-385, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30483705

RESUMO

PURPOSE: To compare the effect on enamel demineralization following fluoride rinse or casein phosphopeptide calcium phosphate complex (CPP-ACP) after fixed appliance orthodontic treatment. METHODS: The study population consisted of 21 post-orthodontic patients (13 females, 8 males, 84 affected teeth) with white spot lesions (WSL). They were divided into 3 groups with 28 affected teeth in each group. Participants in the control group were brushed with fluoride toothpaste twice a day. Participants in the fluoride group were instructed to rinse the mouth with 20mL 0.01% sodium fluoride rinse in addition to brushing twice a day. Participants in CPP-ACP group were instructed to use tooth moss after brushing their teeth twice a day for 6 months. SPSS 17.0 software package was used to analyze the data. RESULTS: Within 6 months after orthodontic treatment, white spot lesions areas of the three groups caused by enamel demineralization were all reduced in different degrees, and the differences of success rate were significant among three groups (P<0.05). CPP-ACP group achieved the highest success rate (51%) than the other group, the fluoride group (44%) and the control group (42%). CONCLUSIONS: Brushing teeth, fluoride rinse and CPP-ACP have certain effect on remineralization of demineralized teeth in 6 months after orthodontic treatment. Compared with brushing and fluoride rinse, CPP-ACP can reduce the area of enamel demineralization more effectively.


Assuntos
Fosfatos de Cálcio , Cariostáticos , Caseínas , Remineralização Dentária , Fosfatos de Cálcio/farmacologia , Cariostáticos/farmacologia , Caseínas/farmacologia , Esmalte Dentário , Feminino , Humanos , Masculino , Fosfopeptídeos
7.
Anal Bioanal Chem ; 408(17): 4649-60, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27129974

RESUMO

Supercritical fluid chromatography was used to resolve and determine ginkgolic acids (GAs) and terpene lactones concurrently in ginkgo plant materials and commercial dietary supplements. Analysis of GAs (C13:0, C15:0, C15:1, and C17:1) was carried out by ESI (-) mass detection. The ESI (-) spectra of GAs simply displayed only the [M-H](-) pseudo-molecular ions, and selected ion monitoring (SIM) for those ions was used for the quantification. Analysis of terpene lactones (ginkgolides A, B, C, J and bilobalide) was complicated by in-source collision-induced dissociation (IS-CID) in the ESI source. Thus, MS analysis could be influenced by the fragmentation pattern produced by the IS-CID. However, it was established that the fragmentation pattern, measured by ion survival yield (ISY), was independent of analyte concentration or matrix at a fixed cone voltage in the ESI source. Therefore, MS with SIM mode was applicable for the analysis of these analytes. The reported method provided consistent and sensitive analysis for the analytes of interest. The LOQs and LODs were determined to be below 100 and 40 ng/mL for GAs and 1 µg/mL and 400 ng/mL for terpene lactones, respectively. Intra- and inter-day precisions were found to be satisfactory with RSDs being below 5.2 %. Analyte recoveries ranged from 87 to 109 %. The developed method was successfully applied to the analysis of 11 ginkgo plant samples and 8 dietary supplements with an analysis time of less than 12 min.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Suplementos Nutricionais/análise , Ginkgo biloba/química , Lactonas/análise , Extratos Vegetais/química , Salicilatos/análise , Terpenos/análise , Cromatografia Gasosa , Cromatografia Líquida
8.
Neurochem Int ; 93: 26-39, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26723542

RESUMO

Glycolysis, mitochondrial substrate oxidation, and the pentose phosphate pathway (PPP) are critical for neuronal bioenergetics and oxidation-reduction homeostasis, but quantitating their fluxes remains challenging, especially when processes such as hexose phosphate (i.e., glucose/fructose-6-phosphate) recycling in the PPP are considered. A hexose phosphate recycling model was developed which exploited the rates of glucose consumption, lactate production, and mitochondrial respiration to infer fluxes through the major glucose consuming pathways of adherent cerebellar granule neurons by replicating [(13)C]lactate labeling from metabolism of [1,2-(13)C2]glucose. Flux calculations were predicated on a steady-state system with reactions having known stoichiometries and carbon atom transitions. Non-oxidative PPP activity and consequent hexose phosphate recycling, as well as pyruvate production by cytoplasmic malic enzyme, were optimized by the model and found to account for 28 ± 2% and 7.7 ± 0.2% of hexose phosphate and pyruvate labeling, respectively. From the resulting fluxes, 52 ± 6% of glucose was metabolized by glycolysis, compared to 19 ± 2% by the combined oxidative/non-oxidative pentose cycle that allows for hexose phosphate recycling, and 29 ± 8% by the combined oxidative PPP/de novo nucleotide synthesis reactions. By extension, 62 ± 6% of glucose was converted to pyruvate, the metabolism of which resulted in 16 ± 1% of glucose oxidized by mitochondria and 46 ± 6% exported as lactate. The results indicate a surprisingly high proportion of glucose utilized by the pentose cycle and the reactions synthesizing nucleotides, and exported as lactate. While the in vitro conditions to which the neurons were exposed (high glucose, no lactate or other exogenous substrates) limit extrapolating these results to the in vivo state, the approach provides a means of assessing a number of metabolic fluxes within the context of hexose phosphate recycling in the PPP from a minimal set of measurements.


Assuntos
Isótopos de Carbono/metabolismo , Hexoses/metabolismo , Modelos Biológicos , Neurônios/metabolismo , Via de Pentose Fosfato , Animais , Cerebelo/citologia , Cerebelo/metabolismo , Cromatografia Líquida , Grânulos Citoplasmáticos/metabolismo , Método de Monte Carlo , Ratos , Ratos Wistar , Espectrometria de Massas em Tandem
9.
Artigo em Inglês | MEDLINE | ID: mdl-25822696

RESUMO

Stevia products are advertised as a zero-calorie sweetener. Glucose should not be an intrinsic component of this product, but it has been identified from some of stevia products in a preliminary study. An UHPLC-UV method was developed for the quantitative determination of glucose from stevia products. After stevia products reacted with 1-phenyl-3-methyl-5-pyrazolone (PMP), PMP derivatives were analysed and glucose was found in seven out of 35 products in the range 0.3-91.5% (w/w). Two products, SPR-12 and SPR-27, showed remarkable amounts of glucose at 61.6% and 91.5%, respectively. In addition, an UHPLC-UV-evaporative light-scattering detector (ELSD) method was developed for the quantitative determination of rebaudioside A, stevioside, rebaudioside D, dulcoside A and steviolbioside from Stevia rebaudiana and related products. In a 12 min run, five steviol glycosides were baseline-separated. ELSD and ultraviolet (UV) detections showed comparable results. The LC methods were validated for linearity, repeatability, accuracy, limits of detection (LOD) and limits of quantification (LOQ). For steviol glycosides, the LODs and LOQs were found to be less than 10 and 30 µg ml(-1), respectively. The RSD for intra- and inter-day analyses was less than 2.5%, and the recovery was 90-94%. For PMP derivative of glucose, the LOD and LOQ were 0.01 and 0.05 µg ml(-1), respectively. Repeatability (RSD) was less than 2.6%; recovery was 98.6-101.7%. The methods are useful for the identification, quality assurance, and adulterant assessment of S. rebaudiana and steviol glycosides sweeteners (stevia products).


Assuntos
Diterpenos do Tipo Caurano/análise , Contaminação de Alimentos/análise , Adoçantes não Calóricos/análise , Antipirina/análogos & derivados , Antipirina/química , Cromatografia Líquida de Alta Pressão , Edaravone , Análise de Alimentos , Glucose/química , Glucosídeos/análise , Glicosídeos/análise , Limite de Detecção , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Stevia/química
10.
J Agric Food Chem ; 63(10): 2674-82, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25727364

RESUMO

GC/MS, chiral GC/MS, and chemometric techniques were used to evaluate a large set (n=104) of tea tree oils (TTO) and commercial products purported to contain TTO. Twenty terpenoids were determined in each sample and compared with the standards specified by ISO-4730-2004. Several of the oil samples that were ISO compliant when distilled did not meet the ISO standards in this study primarily due to the presence of excessive p-cymene and/or depletion of terpinenes. Forty-nine percent of the commercial products did not meet the ISO specifications. Four terpenes, viz., α-pinene, limonene, terpinen-4-ol, and α-terpineol, present in TTOs with the (+)-isomer predominant were measured by chiral GC/MS. The results clearly indicated that 28 commercial products contained excessive (+)-isomer or contained the (+)-isomer in concentrations below the norm. Of the 28 outliers, 7 met the ISO standards. There was a substantial subset of commercial products that met ISO standards but displayed unusual enantiomeric+/-ratios. A class predictive model based on the oils that met ISO standards was constructed. The outliers identified by the class predictive model coincided with the samples that displayed an abnormal chiral ratio. Thus, chiral and chemometric analyses could be used to confirm the identification of abnormal commercial products including those that met all of the ISO standards.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleo de Melaleuca/química , Terpenos/química , Austrália , Isomerismo , Controle de Qualidade , Óleo de Melaleuca/economia
11.
J Pharm Biomed Anal ; 52(2): 173-80, 2010 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-20122811

RESUMO

This paper describes the first analytical method for the determination of four flavonoids (sutherlandins A-D) and four cycloartanol glycosides (sutherlandiosides A-D) from the aerial parts of Sutherlandia frutescens (L.) R. Br. A separation by HPLC was achieved by using a reversed phase (RP-18) column, PDA with ELS detection, and a water/acetonitrile gradient as the mobile phase. The wavelength used for quantification of four flavonoids with the diode array detector was 260 nm. Owing to their low UV absorption, the cycloartanol glycosides were detected by evaporative light scattering. The method was validated for linearity, repeatability, limits of detection (LOD) and limits of quantification (LOQ). The limits of detection and limits of quantification of eight compounds were found to be in the range from 0.1 to 7.5 microg/mL and 0.5 to 25 microg/mL, respectively. The analysis of products showed considerable variation of 1.099-5.224 mg/average weight for the major compound, sutherlandioside B. The eight compounds in plant sample and products of S. frutescens were further confirmed by LC-ESI-TOF. This method involved the use of the [M+H](+) and [M+Na](+) ions in the positive ion mode with extractive ion monitoring (EIM).


Assuntos
Cromatografia Líquida/métodos , Fabaceae , Flavonoides/análise , Glicosídeos/análise , Componentes Aéreos da Planta/química , Calibragem , Cromatografia de Fase Reversa/métodos , Flavonoides/química , Glicosídeos/química , Glicosídeos/classificação , Luz , Limite de Detecção , Espectrometria de Massas/métodos , Estrutura Molecular , Folhas de Planta/química , Caules de Planta/química , Padrões de Referência , Reprodutibilidade dos Testes , Espalhamento de Radiação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Ultravioleta/métodos
12.
J AOAC Int ; 92(2): 633-44, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19485225

RESUMO

A simple and specific analytical method for the quantitative determination of flavonoids from the aerial parts of the Artemisia afra plant samples was developed. By column high-performance liquid chromatography (HPLC) with UV absorption and mass spectrometry (MS) detection, separation was achieved on a reversed-phase octadecylsilyl (C18) column with water, methanol, and acetonitrile, all containing 0.1% acetic acid, as the mobile phase. These methods were used to analyze various species of Artemisia plant samples. The wavelength used for quantification of flavonoids with the diode array detector was 335 nm. The limits of detection (LOD) by HPLC/MS were found to be 7.5, 7.5, 10, 2.0, and 2.0 ng/mL; and by LC-UV the LODs were 500, 500, 500, 300, and 300 ng/mL for apigenin, chrysoeriol, tamarixetin, acacetin, and genkwanin, respectively. The HPLC/MS method was found to be 50-150 times more sensitive than the HPLC-UV method. HPLC/MS coupled with an electrospray ionization interface is described for the identification and quantification of flavonoids in various plant samples. This method involved the use of the [M+H]+ ions of the compounds at mass-to-charge ratio of 1.0606, 301.0712, 317.0661, 285.0763, and 285.0763 (calculated mass), respectively, in the positive ion mode with extractive ion monitoring.


Assuntos
Artemisia/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Apigenina/análise , Cromatografia Líquida de Alta Pressão/estatística & dados numéricos , Dissacarídeos/análise , Flavonas/análise , Espectrometria de Massas/métodos , Plantas Medicinais/química , Quercetina/análogos & derivados , Quercetina/análise , Especificidade da Espécie , Espectrofotometria Ultravioleta
13.
Commun Agric Appl Biol Sci ; 73(4): 841-51, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19226834

RESUMO

A rapid multi-residue method for the simultaneous analysis of 3 herbicides and 8 organochlorine pesticides (OCPs) in agricultural soils has been developed, using ultrasonic solvent extraction coupled with gas chromatography-mass spectrometry (GC-MS). The recoveries ranged from 81% to 117% with a relative standard deviation (R.S.D) lower than 15%. The limits of quantification (LOQs) ranged from 0.03 to 1.06 microg x kg(-1) dry weight for different pesticides studied. The proposed method has been applied to investigate the 11 pesticide residues in agricultural soils collected from Liaoning Province, northeast of China. 3 OCPs and 3 herbicides were identified. Acetochlor, atrazine, butachtor were measured in the relatively high level with values ranging from 0.53 to 203.18 microg x kg(-1), 0.14 to 21.20 microg x kg(-1), <0.05 to 30.87 microg x kg(-1), respectively. All the OCPs residue levels were below 10 microg x kg(-1). The concentration of the eleven pesticides in this study was compared with the date of other countries reported and the corresponding limiting values used in Netherland, USA, Canada, Vietnam and Thailand. Among the herbicide residues, there was a significant relativity between soil utilizing types and their residue concentration. It seems that the monitoring action for soil contamination caused by commonly-used herbicides should be enhanced according to soil utilizing types, especially acetochlor in maize field.


Assuntos
Agricultura , Cromatografia Gasosa-Espectrometria de Massas/métodos , Herbicidas/análise , Praguicidas/análise , Poluentes do Solo/análise , China , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise
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