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1.
Planta Med ; 87(12-13): 1069-1079, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34243208

RESUMO

The presence of plant toxins and/or cyanotoxins in food supplements implies consumer health risks. Therefore, a targeted ultra-high performance liquid chromatographic-tandem mass spectrometric method to detect/quantify 25 toxins simultaneously in food supplement formulations was developed and validated. Full validation for tablets/powders and secondary validation for a liquid and soft gel capsule indicated that most compounds were efficiently extracted (≥ 75%), while others were only partly extracted (18 - 61%). Trueness was fulfilled (70 - 120%), with some exceptions (mostly at the lowest validation level). Intralaboratory repeatability, intra- and interlaboratory reproducibility values of ≤ 20%, ≤ 25%, and ≤ 25% were obtained for most, respectively. Matrix effects were found to be significant for most compounds. Good sensitivity (µg/kg level) was observed for galegin(e), lycopsamine, lycorine, rubiadin, skimmiamine, and vascin(e), in contrast to helveticoside, lucidin, lucidin-3-primveroside, plumbagin(e), and thujone, which were detected at the mg/kg level. The other compounds were characterized by a sensitivity between 10 to 1000 µg/kg. The validated methodology was applied for 52 food supplements (tablets, capsules, liquids/syrup, etc.) purchased from the Belgian market. In more than 25% of the samples, one or more toxins were detected (concentrations determined using standard addition). Lycopsamine, microcystin LR, solamargine, thujone, and vasicin(e) were the most frequently detected toxins. A clear link between the toxins detected and the plant species on the food supplement ingredient list could not always be established. This generic "dilute-and-shoot" procedure can be used for further research on toxins in food supplements and by extension other plant/algae-based food/feed commodities (herbs, edible flowers, etc.).


Assuntos
Suplementos Nutricionais , Toxinas Biológicas/análise , Bélgica , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
2.
Artigo em Inglês | MEDLINE | ID: mdl-33861158

RESUMO

An analytical workflow including mass spectral library, generic sample preparation, chromatographic separation, and analysis by high-resolution mass spectrometry (HRMS) was developed to gain insight into the occurrence of plant toxins, mycotoxins and phytoestrogens in plant-based food. This workflow was applied to 156 compounds including 90 plant toxins (pyrrolizidine alkaloids, tropane alkaloids, glycoalkaloids, isoquinoline alkaloids and aristolochic acids), 54 mycotoxins (including ergot alkaloids and Alternaria toxins) and 12 phytoestrogens (including isoflavones, lignans and coumestan) in plant-based protein ingredients, cereal and pseudo-cereal products. A mass spectral library was built based on fragmentation spectra collected at 10 different collision energies in both positive and negative ionisation modes for each toxin. Emphasis was put on a generic QuEChERS-like sample preparation followed by ultra-high-pressure liquid chromatography using alkaline mobile phase allowing the separation of more than 50 toxic pyrrolizidine alkaloids. HRMS acquisition comprised a full-scan event for toxins detection followed by data-dependent MS2 for toxin identification against mass spectrum. Method performance was evaluated using fortified samples in terms of sensitivity, repeatability, reproducibility and recovery. All toxins were positively identified at levels ranging from 1 µg kg-1 to 100 µg kg-1. Quantitative results obtained by a standard addition approach met SANTE/12682/2019 criteria for 132 out of 156 toxins. Such a workflow using generic, sensitive and selective multi-residue method allows a better insight into the occurrence of regulated and non-regulated toxins in plant-based foods and to conduct safety evaluation and risk assessments when needed.


Assuntos
Contaminação de Alimentos/análise , Fitoestrógenos/análise , Toxinas Biológicas/análise , Alcaloides/análise , Técnicas Biossensoriais , Cromatografia Líquida de Alta Pressão , Grão Comestível/química , Humanos , Extração Líquido-Líquido , Pisum sativum/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glycine max/química , Espectrometria de Massas em Tandem , Fluxo de Trabalho
3.
Toxins (Basel) ; 12(8)2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32707815

RESUMO

Food, by nature, is a biological substrate and is therefore capable of supporting the growth of microbials that are potential producers of toxic compounds [...].


Assuntos
Contaminação de Alimentos/análise , Toxinas Biológicas/análise , Bioensaio , Cromatografia Líquida , Suplementos Nutricionais/análise , Imunoensaio , Espectrometria de Massas em Tandem , Toxinas Biológicas/metabolismo
4.
Toxicon ; 172: 53-60, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31704310

RESUMO

"Chiniy-tref" (CT) is a traditional preparation used in folk medicine in Martinique Island (French West Indies) that is nowadays mainly taken orally to prevent or act against any "manifestation of evil". CT is easily prepared at home by macerating larvae of the endemic swallowtail Battus polydamas (ssp.) cebriones (Dalman, 1823), sometimes accompanied by a leaf of its host-plant Aristolochia trilobata L., in commercial rum. We have previously reported the detection of nephrotoxic and carcinogenic aristolochic acids (AAs) I and II in CT, leading the Regional Health Agency (ARS) of Martinique to issue an alert regarding the potential risks associated with its consumption in 2015. In order to complete the toxicity risk assessment for oral consumption of CT, a full qualitative analysis of AAs and their analogues (AAAs) was performed, as well as a quantitative determination of the major AAs, namely AAs I and II. The phytochemical profiling of AAAs present in CT, that also corresponds to that of B. polydamas cebriones larvae feeding on A. trilobata, has been established for the first time by ultra-high performance liquid chromatography/electrospray ionization quadrupole time of-flight tandem mass spectrometry. AAs I and II were quantified in a small panel of tinctures by using a validated UHPLC/UV method, allowing us to estimate the probable daily intakes of these toxins by CT consumers. The results proved the existence of a real risk of renal toxicity and carcinogenicity associated with the chronic oral consumption of CT in Martinique, and more generally of similar "snake bottles" throughout the Caribbean.


Assuntos
Aristolochia/química , Ácidos Aristolóquicos/análise , Borboletas/química , Medicina Tradicional , Animais , Ácidos Aristolóquicos/química , Larva/química , Martinica , Toxinas Biológicas/análise , Toxinas Biológicas/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-31294678

RESUMO

The use of food supplements is increasing. They are marketed as beneficial for health, well-being, physical or mental condition and performance, or to prevent diseases. Producers add synthetic compounds or illicit herbal material to food supplements to claim desired effects. Claims made to support marketing without scientific evidence are, however, illegal. Intake of adulterated food supplements may lead to serious adverse effects. The aim of this paper is to report the results of analyses of (adulterated) food supplements conducted by the Netherlands Food and Consumer Product Safety Authority between October 2013 and October 2018. In total, 416 supplements were analysed of which 264 (64%) contained one or more pharmacological active substances or plant toxins, such as caffeine, synephrine, sildenafil, icariin, sibutramine, higenamine, hordenine, phenethylamine, methylsynephrine, DMAA, phenolphthalein, octopamine and ephedrine. When compared to dose levels that are considered safe, daily doses of the substances in the food supplements were sometimes much higher, causing a risk for consumers who are unaware of the presence of these pharmacologically active substances. In many cases, neither food nor medicines legislation (easily) enables enforcement actions. This means that some products containing pharmacologically active substances (i.e. synthetic medicines and their illicit analogues), stay available on the market. An undesirable situation because for many of these substances no detailed toxicity data are available.


Assuntos
Suplementos Nutricionais/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Preparações Farmacêuticas/análise , Toxinas Biológicas/análise , Cromatografia Líquida , Humanos , Países Baixos , Medição de Risco , Espectrometria de Massas em Tandem
6.
J Food Drug Anal ; 27(2): 415-427, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987713

RESUMO

The unintentional ingestion of toxic compounds in herbs is not uncommon in many parts of the world. To provide timely and life-saving care in the emergency department, it is essential to develop a point-of-care analytical method that can rapidly identify these toxins in herbs. Since electrospray laser desorption ionization mass spectrometry (ELDI/MS) has been successfully used to characterize non-volatile chemical compounds without sample preparation, it was used to identify toxic herbal compounds in this study. The herbal toxins were collected either by sweeping a metallic probe across the surface of a freshly cut herb section or by directly sampling extracts of ground herbal powder. The analytes on the probe were then desorbed, ionized and detected using ELDI/MS, wherein analysis of the herbal toxins was completed within 30 s. This approach allows for the rapid morphological recognition of herbs and early point-of-care identification of herbal toxins for emergency management and is promising in providing important toxicological information to ensure appropriate medical treatment.


Assuntos
Serviços Médicos de Emergência , Plantas Tóxicas/química , Toxinas Biológicas/análise , Aconitina/análogos & derivados , Aconitina/análise , Flavanonas/análise , Humanos , Piridoxina/análogos & derivados , Piridoxina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
7.
Mikrochim Acta ; 186(4): 219, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30847660

RESUMO

The authors describe an aptamer based assay for the mycotoxin T-2. The method is making use of exponential isothermal amplification reaction (EXPAR) and fluorescent silver nanoclusters (AgNCs). Free T-2 and cDNA (which is a DNA that is partially complementary to the aptamer) compete for binding to aptamer-modified magnetic beads. The cDNA collected by magnetic separation can be used as a primer to trigger EXPAR to obtain ssDNA. The C-base-rich ssDNA binds and reduces Ag(I) ion to form fluorescent AgNCs. Fluorescence is measured at excitation/emission wavelengths of 480/525 nm. T-2 can be detected by fluorometry with a detection limit as low as 30 fg·mL-1. The method was applied to analyse spiked oat and corn, and the average recoveries ranged from 97.3 to 102.3% and from 95.9 to 107.5%, respectively. The results were in good agreement with data of the commercial ELISA kit. The assay is highly sensitive, has a wide analytical range, good specificity and reliable operation. It provides a promising alternative for the standard method for quantitative detection of T-2. Graphical abstract Schematic presentation of fluorometric assay for T-2 based on aptamer-functionalized magnetic beads exponential, isothermal amplification reaction (EXPAR) and fluorescent silver nanoclusters (AgNCs).


Assuntos
Aptâmeros de Nucleotídeos/química , DNA/química , Óxido Ferroso-Férrico/química , Nanopartículas Metálicas/química , Prata/química , Toxinas Biológicas/análise , Avena/química , Corantes Fluorescentes/química , Fluorometria/métodos , Limite de Detecção , Microesferas , Tamanho da Partícula , Propriedades de Superfície , Temperatura , Zea mays/química
8.
Environ Sci Pollut Res Int ; 25(32): 31971-31986, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30229484

RESUMO

Some of pathogenic bacteria and fungi have the ability to produce fetal toxins which may be the direct causes of cytotoxicity or cellular dysfunction in the colonization site. Biological and non-biological environmental factors, challenge and microbes influence the effect of toxins on these pathogens. Modern research mentions that many natural materials can reduce the production of toxins in pathogenic microbes. However, researches that explain the mechanical theories of their effects are meager. This review aimed to discuss the ameliorative potential role of plant-derived compounds and probiotics to reduce the toxin production of food-borne microbes either in poultry bodies or poultry feedstuff. Moreover, studies that highlight their own toxicological mechanisms have been discussed. Adding natural additives to feed has a clear positive effect on the enzymatic and microbiological appearance of the small intestine without any adverse effect on the liver. Studies in this respect were proposed to clarify the effects of these natural additives for feed. In conclusion, it could be suggested that the incorporation of probiotics, herbal extracts, and herbs in the poultry diets has some beneficial effects on productive performance, without a positive impact on economic efficiency. In addition, the use of these natural additives in feed has a useful impact on the microbiological appearance of the small intestine and do not have any adverse impacts on intestinal absorption or liver activity as evidenced by histological examination.


Assuntos
Ração Animal/análise , Anti-Infecciosos/farmacologia , Extratos Vegetais/farmacologia , Plantas/química , Probióticos/farmacologia , Toxinas Biológicas/metabolismo , Ração Animal/microbiologia , Animais , Anti-Infecciosos/análise , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Fungos/efeitos dos fármacos , Fungos/metabolismo , Extratos Vegetais/análise , Aves Domésticas/crescimento & desenvolvimento , Probióticos/análise , Toxinas Biológicas/análise
9.
Chin J Integr Med ; 24(6): 403-405, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29752692

RESUMO

Chronic kidney disease (CKD) is a major disease that threatens human health. With the progression of CKD, the risk of cardiovascular death increases, which is associated with the elevated levels of uremic toxins (UTs). Representative toxins such as indoxyl sulfate and p-cresyl sulfate are involed in CKD progression and cardiovascular events inseparable from the key role of endothelial dysfunction. The therapeutic strategies of UTs are aimed at signaling pathways that target the levels and damage of toxins in modern medicine. There is a certain relevance between toxins and "turbid toxin" in the theory of Chinese medicine (CM). CM treatments have been demonstrated to reduce the damage of gut-derived toxins to the heart, kidney and blood vessels. Modern medicine still lacks evidence-based therapies, so it is necessary to explore the treatments of CM.


Assuntos
Mucosa Intestinal/metabolismo , Medicina Tradicional Chinesa , Insuficiência Renal Crônica/tratamento farmacológico , Toxinas Biológicas/metabolismo , Uremia/metabolismo , Humanos , Transdução de Sinais/efeitos dos fármacos , Toxinas Biológicas/análise
10.
PLoS One ; 12(10): e0186010, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29016645

RESUMO

BACKGROUND AND AIM: Numerous outcome studies and interventional trials in hemodialysis (HD) patients are based on uremic toxin concentrations determined at one single or a limited number of time points. The reliability of these studies however entirely depends on how representative these cross-sectional concentrations are. We therefore investigated the variability of predialysis concentrations of uremic toxins over time. METHODS: Prospectively collected predialysis serum samples of the midweek session of week 0, 1, 2, 3, 4, 8, 12, and 16 were analyzed for a panel of uremic toxins in stable chronic HD patients (N = 18) while maintaining dialyzer type and dialysis mode during the study period. RESULTS: Concentrations of the analyzed uremic toxins varied substantially between individuals, but also within stable HD patients (intra-patient variability). For urea, creatinine, beta-2-microglobulin, and some protein-bound uremic toxins, Intra-class Correlation Coefficient (ICC) was higher than 0.7. However, for phosphorus, uric acid, symmetric and asymmetric dimethylarginine, and the protein-bound toxins hippuric acid and indoxyl sulfate, ICC values were below 0.7, implying a concentration variability within the individual patient even exceeding 65% of the observed inter-patient variability. CONCLUSION: Intra-patient variability may affect the interpretation of the association between a single concentration of certain uremic toxins and outcomes. When performing future outcome and interventional studies with uremic toxins other than described here, one should quantify their intra-patient variability and take into account that for solutes with a large intra-patient variability associations could be missed.


Assuntos
Soluções para Hemodiálise/química , Diálise Renal , Insuficiência Renal Crônica/terapia , Toxinas Biológicas/análise , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Arginina/análogos & derivados , Arginina/análise , Creatinina/análise , Feminino , Hipuratos/análise , Humanos , Indicã/análise , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Fósforo/análise , Ureia/análise , Ácido Úrico/análise , Microglobulina beta-2/análise
11.
Food Res Int ; 99(Pt 1): 155-165, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28784472

RESUMO

A deeper knowledge of the chemical composition of coffee silverskin (CS) is needed due to the growing interest in its use as a food additive or an ingredient of dietary supplements. Accordingly, the aim of this paper was to investigate the metabolic profile of aqueous extracts of two varieties of CS, Coffee arabica (CS-A), Coffee canephora var. robusta (CS-R) and of a blend of the two (CS-b) and to compare it to the profile of Coffee arabica green coffee (GC). Chlorogenic acids, caffeine, furokauranes, and atractyligenins, phytotoxins not previously detected in CS, were either identified or tentatively assigned. An unknown compound, presumably a carboxyatractyligenin glycoside was detected only in GC. Caffeine and chlorogenic acids were quantified while the content of furokauranes and atractyligens was estimated. GC and CS were also characterized in terms of total polyphenols and antioxidant capacity. Differences in the metabolites distribution, polyphenols and antioxidant capacity in GC and CS were detailed.


Assuntos
Antioxidantes/análise , Cromatografia Líquida de Alta Pressão , Coffea/química , Análise de Alimentos/métodos , Metabolômica/métodos , Compostos Fitoquímicos/análise , Sementes/química , Espectrometria de Massas por Ionização por Electrospray , Toxinas Biológicas/análise , Atractilosídeo/análogos & derivados , Atractilosídeo/análise , Cafeína/análise , Ácido Clorogênico/análise , Coffea/classificação , Sementes/classificação
12.
Toxins (Basel) ; 9(7)2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28661437

RESUMO

Canadian milkvetch (Astragalus canadensis) is a North American plant species in the legume family and some of this plant is fatally poisonous to livestock. The poisoning is attributed to the natural occurrence of notrotoxins, i.e., 3-nitropropanoic acid and 3-nitropropanol, present as aglycones and conjugated forms in the plant. Those compounds cause nitrite oxidization of hemoglobin and inhibition of cellular metabolism. To determine the toxicity of the plant, it is very important to develop an analytical method for the contents of the compounds in the plant. In this study, we have successfully developed an extraction procedure followed by HPLC-UV analysis to simultaneously analyze notrotoxins. The aglycones could be released from its conjugated forms in the freeze dried plant and extracted by water at room temperature. An HPLC-UV method using a Phenomenex Kinetex 2.6 µ F5 100 Å 100 × 4.6 mm column with pH 3.5 phosphonate buffer as mobile phase have been developed and validated for the detection of the two compounds at 210 nm. This developed procedure for the analysis of 3-nitropropanoic acid and 3-nitropropanol has proven simple and efficient and it has been successfully applied for batch sample analysis.


Assuntos
Astrágalo/química , Nitrocompostos/análise , Extratos Vegetais/análise , Plantas Tóxicas/química , Propanóis/análise , Propionatos/análise , Toxinas Biológicas/análise , Cromatografia Líquida de Alta Pressão/métodos , Liofilização , Espectrofotometria Ultravioleta
13.
Toxins (Basel) ; 8(12)2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27999389

RESUMO

Latrodectus tredecimguttatus is a kind of highly venomous black widow spider, with toxicity coming from not only venomous glands but also other parts of its body as well as newborn spiderlings and eggs. Up to date, although L. tredecimguttatus eggs have been demonstrated to be rich in proteinaceous toxins, there is no systematic investigation on such active components at transcriptome level. In this study, we performed a high-throughput transcriptome sequencing of L. tredecimguttatus eggs with Illumina sequencing technology. As a result, 53,284 protein-coding unigenes were identified, of which 14,185 unigenes produced significant hits in the available databases, including 280 unigenes encoding proteins or peptides homologous to known proteinaceous toxins. GO term and KEGG pathway enrichment analyses of the 280 unigenes showed that 375 GO terms and 18 KEGG pathways were significantly enriched. Functional analysis indicated that these unigene-coded toxins have the bioactivities to degrade tissue proteins, inhibit ion channels, block neuromuscular transmission, provoke anaphylaxis, induce apoptosis and hyperalgesia, etc. No known typical proteinaceous toxins in L. tredecimguttatus venomous glands, such as latrotoxins, were identified, suggesting that the eggs have a different toxicity mechanism from that of the venom. Our present transcriptome analysis not only helps to reveal the gene expression profile and toxicity mechanism of the L. tredecimguttatus eggs, but also provides references for the further related researches.


Assuntos
Proteínas de Artrópodes/análise , Viúva Negra , Óvulo/química , Toxinas Biológicas/análise , Animais , Proteínas de Artrópodes/genética , DNA Complementar/genética , Perfilação da Expressão Gênica , Ontologia Genética , Toxinas Biológicas/genética
14.
Toxicon ; 114: 28-30, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26879332

RESUMO

"Chiniy-trèf" is a traditional medicinal preparation used in Martinique, French West Indies, for the prevention of all kinds of attempted poisoning and hex. It is produced by the maceration in alcohol (mostly rum) of larvae (caterpillars) of the butterfly Battus polydamas ssp. cebriones, feeding on the leaves of Aristolochia trilobata. Aristolochic acids I and II that are well-known nephrotoxic and carcinogenic substances were identified on two samples of "chiniy-trèfl" by chromatographic methods.


Assuntos
Ácidos Aristolóquicos/isolamento & purificação , Borboletas/química , Medicina Tradicional , Toxinas Biológicas/isolamento & purificação , Animais , Aristolochia/química , Ácidos Aristolóquicos/análise , Ácidos Aristolóquicos/química , Borboletas/fisiologia , Comportamento Alimentar , Larva/química , Larva/fisiologia , Martinica , Toxinas Biológicas/análise , Toxinas Biológicas/química
15.
Toxicon ; 99: 36-43, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25772859

RESUMO

Larkspurs (Delphinium spp.) are poisonous plants on rangelands throughout the Western United States and Canada. Larkspur-induced poisoning in cattle is due to norditerpene alkaloids that are represented by two main structural groups of norditerpene alkaloids, the N-(methylsuccinimido) anthranoyllycoctonine type (MSAL-type) and the non-MSAL type. Information on the alkaloid composition and resulting toxicity in mice and cattle is lacking for a number of Delphinium species, including Delphinium stachydeum. The objective of this study was to determine the alkaloid composition of D. stachydeum and to characterize its relative toxicity in mice and cattle compared to two reference species Delphinium barbeyi and Delphinium occidentale. D. stachydeum contains the non-MSAL-type alkaloids but not the MSAL-type alkaloids. D. stachydeum was less toxic than D. barbeyi and D. occidentale in the mouse model. D. stachydeum was less toxic than the MSAL-containing D. barbeyi but much more toxic than the non-MSAL-containing D. occidentale in cattle as measured by heart rate and time of exercise. These results indicate that predictions of Delphinium toxicity can't be accurately made based solely on results from the mouse model or the absence of the MSAL-type alkaloids in the plant.


Assuntos
Alcaloides/toxicidade , Doenças dos Bovinos/fisiopatologia , Delphinium/toxicidade , Componentes Aéreos da Planta/toxicidade , Extratos Vegetais/toxicidade , Intoxicação por Plantas/veterinária , Toxinas Biológicas/toxicidade , Alcaloides/análise , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Bovinos , Doenças dos Bovinos/etiologia , Delphinium/química , Delphinium/crescimento & desenvolvimento , Diterpenos/análise , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/toxicidade , Humanos , Coxeadura Animal/etiologia , Dose Letal Mediana , Masculino , Camundongos , Debilidade Muscular/etiologia , Nevada , Oregon , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/crescimento & desenvolvimento , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Intoxicação por Plantas/etiologia , Intoxicação por Plantas/fisiopatologia , Especificidade da Espécie , Taquicardia/etiologia , Toxinas Biológicas/análise , Toxinas Biológicas/química , Toxinas Biológicas/isolamento & purificação , Tremor/etiologia , Utah
16.
Macromol Biosci ; 15(5): 589-99, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25654999

RESUMO

Since the birth of tissue engineering, it has been redefined to include not only the development of tissues for clinical use, but also in vitro models for the study of tissue physiology and pathology. Great strides have been accomplished in the design of in vitro tissue models, yet one area in which they are underrepresented, but where they can have an immediate impact, is the development of platforms for drug screening. By providing more in vivo-like cell environments, such models could address the growing concerns about drug failures due to lack of efficacy or unexpected side effects. This review aims to address the interface between substrate compliance and cell responsiveness to toxins and drugs since compliance has been established as a major determinate of overall cell fate. Here, results from 2D substrates and 3D matrices are discussed. Additionally, examples of biomaterial-based high-throughput stiffness assays in drug screening are presented.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Matriz Extracelular/metabolismo , Preparações Farmacêuticas/análise , Toxinas Biológicas/análise , Animais , Materiais Biocompatíveis/farmacologia , Humanos , Teste de Materiais
17.
J Sci Food Agric ; 95(8): 1577-83, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25156477

RESUMO

Labrador tea is a name for the dried leaves of Rhododendron groenlandicum, R. tomentosum or R. neoglandulosum (family Ericaceae, previously genus Ledum) as well as for the beverage native to North America, which is made from them. The above species are rich in the essential oil, which gives a conifer aroma to the tisane. Labrador tea is a valuable source of ascorbic acid, with tonic, improving digestion and relaxing activity. However, this beverage should not be drunk more than once daily because of the ledol and grayanotoxin toxicity. The common recipe for making Labrador tea is to add one teaspoonful of dried leaves to one cup of boiling water and to brew for 5 min. It is often sweetened or enriched with other flavors. Additionally, Labrador tea dried leaves are used to spice meat, soups, sauces, salads, beer, cakes and other dishes. In agriculture, its insecticidal properties can be useful for controlling pests.


Assuntos
Bebidas , Manipulação de Alimentos , Inocuidade dos Alimentos , Ledum , Diterpenos/análise , Diterpenos/toxicidade , Flavonoides/análise , Manipulação de Alimentos/métodos , Humanos , Inseticidas , Ledum/química , Ledum/toxicidade , América do Norte , Óleos Voláteis/análise , Fitoterapia , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Sesquiterpenos/análise , Sesquiterpenos/toxicidade , Especiarias , Toxinas Biológicas/análise
18.
Anal Chem ; 87(2): 967-74, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25496503

RESUMO

Type 2 ribosome-inactivating protein toxins (RIP-II toxins) were enriched and purified prior to enzymatic digestion and LC-MS analysis. The enrichment of the RIP-II family of plant proteins, such as ricin, abrin, viscumin, and volkensin was based on their affinity for galactosyl moieties. A macroporous chromatographic material was modified with a galactose-terminated substituent and packed into miniaturized columns that were used in a chromatographic system to achieve up to 1000-fold toxin enrichment. The galactose affinity of the RIP-II proteins enabled their selective enrichment from water, beverages, and extracts of powder and wipe samples. The enriched fractions were digested with trypsin and RIP-II peptides were identified based on accurate mass LC-MS data. Their identities were unambiguously confirmed by LC-MS/MS product ion scans of peptides unique to each of the toxins. The LC-MS detection limit achieved for ricin target peptides was 10 amol and the corresponding detection limit for the full method was 10 fmol/mL (0.6 ng/mL). The affinity enrichment method was applied to samples from a forensic investigation into a case involving the illegal production of ricin and abrin toxins.


Assuntos
Cromatografia de Afinidade/métodos , Cromatografia Líquida/métodos , Galactose/metabolismo , Extratos Vegetais/química , Proteínas Inativadoras de Ribossomos Tipo 2/análise , Espectrometria de Massas em Tandem/métodos , Tripsina/metabolismo , Abrina/análise , Abrina/isolamento & purificação , Abrina/metabolismo , Adulto , Humanos , Masculino , Fragmentos de Peptídeos/análise , Proteínas Inativadoras de Ribossomos Tipo 2/isolamento & purificação , Proteínas Inativadoras de Ribossomos Tipo 2/metabolismo , Ricina/análise , Ricina/isolamento & purificação , Ricina/metabolismo , Toxinas Biológicas/análise , Toxinas Biológicas/isolamento & purificação , Toxinas Biológicas/metabolismo
19.
Zhongguo Zhong Yao Za Zhi ; 40(18): 3515-23, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26983192

RESUMO

Cytometric bead array (CBA) is a new analytical technique, which can achieve real-time and rapid detection of targeted components in a small amount of sample. With many advantages of high throughput screening, high specificity and sensitivity, low cost, easy operation and good repeatability, this CBA technique has been widely used for the detection of various components in foods, agricultural products and environmental samples. Recently, it has got significant development in rapid detection of small molecules. This review briefly introduced the theory of CBA technique, summarized the application in the analysis of small molecules, such as mycotoxins, pesticide residues, shellfish toxins, and then prospected the application of trace small molecules detection in the complex matrices of traditional Chinese medicine and the development trend of it.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Imunoensaio/métodos , Praguicidas/análise , Toxinas Biológicas/análise , Contaminação de Medicamentos , Ensaios de Triagem em Larga Escala/instrumentação , Imunoensaio/instrumentação , Microesferas
20.
Toxins (Basel) ; 6(2): 539-55, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24476713

RESUMO

Raw or dried gallbladders of cyprinid fish have long been ingested as a traditional medicine in the Asian countries, particularly in China, for ameliorating visual acuity, rheumatism, and general health; however, sporadic poisoning incidences have occurred after their ingestion. The poisoning causes complex symptoms in patients, including acute renal failure, liver dysfunction, paralysis, and convulsions of limbs. The causative substance for the poisoning was isolated, and its basic properties were examined. The purified toxin revealed a minimum lethal dose of 2.6 mg/20 g in mouse, when injected intraperitoneally. The main symptoms were paralysis and convulsions of the hind legs, along with other neurological signs. Liver biopsy of the euthanized mice clearly exhibited hepatocytes necrosis and infiltration of neutrophils and lymphocytes, suggesting the acute dysfunction of the liver. Blood tests disclosed the characteristics of acute renal failure and liver injury. Infrared (IR) spectrometry, fast atom bombardment (FAB) mass spectrometry, and 1H- and 13C-nuclear magnetic resonance (NMR) analysis indicated, a molecular formula of C27H48O8S, containing a sulfate ester group for the toxin. Thus, we concluded that the structure of carp toxin to be 5α-cyprinol sulfate (5α-cholestane-3α, 7α, 12α, 26, 27-pentol 26-sulfate). This indicated that carp toxin is a nephro- and hepato- toxin, which could be the responsible toxin for carp bile poisoning in humans.


Assuntos
Cyprinidae , Doenças Transmitidas por Alimentos , Animais , Bile/química , Colestanóis/análise , Colestanóis/química , Colestanóis/toxicidade , Ingestão de Alimentos , Vesícula Biliar , Humanos , Toxinas Biológicas/análise , Toxinas Biológicas/química , Toxinas Biológicas/toxicidade
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