Infestation and Quantification of Ochratoxigenic Fungi in Barley and Wheat Naturally Contaminated with Ochratoxin A.

PubMed

Kuruc, Julie; Hegstad, Justin; Lee, Hyun Jung; Simons, Kristin; Ryu, Dojin; Wolf-Hall, Charlene

2015-07-01

Cereal grains are a significant source of ochratoxin A (OTA) in the human diet. Multiple ochratoxigenic Aspergillus and Penicillium spp. have been reported as contaminants on various cereal grains around the world, although relatively few species dominate in any given location. Efforts to mitigate the risk of fungal contamination and OTA accumulation can be made pre- and postharvest. Still, a rapid and reliable screening method is sought that can be used to predict the OTA level of a sample and to inform risk assessments prior to processing. In this study, we assessed the efficacy of two OTA-related indices for OTA level prediction. Infestation rates were determined by direct plating for freshly harvested and stored barley, durum, and hard red spring wheat samples (n = 139) with known OTA levels. Presumptive ochratoxigenic isolates were tested for their ability to produce OTA. The nonribosomal peptide synthase (otanpsPN) involved in OTA biosynthesis was used to quantify ochratoxigenic fungi in barley and wheat. Viable Penicillium verrucosum was present in 45% of the samples. In total, 62.7% (n = 110) of the P. verrucosum isolates tested produced OTA on dichloran yeast extract sucrose 18% glycerol agar. Both OTA level and infestation rate (r = 0.30), as well as OTA level and otanpsPN concentration (r = 0.56), were weakly correlated. Neither infestation rate nor otanpsPN concentration is a reliable predictor of OTA level in a sample.

Ochratoxin A and human health risk: a review of the evidence.

PubMed

Bui-Klimke, Travis R; Wu, Felicia

2015-01-01

Ochratoxin A (OTA) is a mycotoxin produced by several fungal species including Aspergillus ochraceus, A. carbonarius, A. niger, and Penicillium verrucosum. OTA causes nephrotoxicity and renal tumors in a variety of animal species; however, human health effects are less well-characterized. Various studies have linked OTA exposure with the human diseases Balkan endemic nephropathy (BEN) and chronic interstitial nephropathy (CIN), as well as other renal diseases. This study reviews the epidemiological literature on OTA exposure and adverse health effects in different populations worldwide, and assesses the potential human health risks of OTA exposure. Epidemiological studies identified in a systematic review were used to calculate unadjusted odds ratios for OTA associated with various health endpoints. With one exception, there appears to be no statistically significant evidence for human health risks associated with OTA exposure. One Egyptian study showed a significantly higher risk of nephritic syndrome in those with very high urinary OTA levels compared with relatively unexposed individuals; however, other potential risk factors were not controlled for in the study. Larger cohort or case-control studies are needed in the future to better establish potential OTA-related human health effects, and further duplicate-diet studies are needed to validate biomarkers of OTA exposure in humans.

A New Ochratoxin A Biodegradation Strategy Using Cupriavidus basilensis Őr16 Strain

PubMed Central

Krifaton, Csilla; Szoboszlay, Sándor; Kukolya, József; Szőke, Zsuzsanna; Kőszegi, Balázs; Albert, Mihály; Barna, Teréz; Mézes, Miklós; Kovács, Krisztina J.; Kriszt, Balázs

2014-01-01

Ochratoxin-A (OTA) is a mycotoxin with possibly carcinogenic and nephrotoxic effects in humans and animals. OTA is often found as a contaminant in agricultural commodities. The aim of the present work was to evaluate OTA-degrading and detoxifying potential of Cupriavidus basilensis ŐR16 strain. In vivo administration of OTA in CD1 male mice (1 or 10 mg/kg body weight for 72 hours or 0.5 mg/kg body weight for 21 days) resulted in significant elevation of OTA levels in the blood, histopathological alterations- and transcriptional changes in OTA-dependent genes (annexinA2, clusterin, sulphotransferase and gadd45 and gadd153) in the renal cortex. These OTA-induced changes were not seen in animals that have been treated with culture supernatants in which OTA was incubated with Cupriavidus basilensis ŐR16 strain for 5 days. HPLC and ELISA methods identified ochratoxin α as the major metabolite of OTA in Cupriavidus basilensis ŐR16 cultures, which is not toxic in vivo. This study has demonstrated that Cupriavidus basilensis ŐR16 efficiently degrade OTA without producing toxic adventitious metabolites. PMID:25302950

[Determination of ochratoxin A by ELISA I. Study on the preparation of ochratoxin a antigen].

PubMed

Chen, Xuelan; Xu, Yang; Wu, Chenggang

2002-02-01

Ochratoxin A (OTA) antigen was prepared by activated ester method. Factors influencing OTA antigen were discussed and the optimum conditions was found by L9(3(4)) orthogonal design. The results showed that when the mole ratio was OTA:BSA = 20:1, OTA:NHS(N-hydroxy-succinamide):DCC(dicyclohexylcarbodiimide) = 1:2:4, the activate time was 120 min and the conjugation time was 90 min, the utilization of OTA could reach 48.2% and the best conjugation ratio of OTA and BSA was 9.64.

Detection of ochratoxin A contamination in stored wheat using near-infrared hyperspectral imaging

NASA Astrophysics Data System (ADS)

Senthilkumar, T.; Jayas, D. S.; White, N. D. G.; Fields, P. G.; Gräfenhan, T.

2017-03-01

Near-infrared (NIR) hyperspectral imaging system was used to detect five concentration levels of ochratoxin A (OTA) in contaminated wheat kernels. The wheat kernels artificially inoculated with two different OTA producing Penicillium verrucosum strains, two different non-toxigenic P. verrucosum strains, and sterile control wheat kernels were subjected to NIR hyperspectral imaging. The acquired three-dimensional data were reshaped into readable two-dimensional data. Principal Component Analysis (PCA) was applied to the two dimensional data to identify the key wavelengths which had greater significance in detecting OTA contamination in wheat. Statistical and histogram features extracted at the key wavelengths were used in the linear, quadratic and Mahalanobis statistical discriminant models to differentiate between sterile control, five concentration levels of OTA contamination in wheat kernels, and five infection levels of non-OTA producing P. verrucosum inoculated wheat kernels. The classification models differentiated sterile control samples from OTA contaminated wheat kernels and non-OTA producing P. verrucosum inoculated wheat kernels with a 100% accuracy. The classification models also differentiated between five concentration levels of OTA contaminated wheat kernels and between five infection levels of non-OTA producing P. verrucosum inoculated wheat kernels with a correct classification of more than 98%. The non-OTA producing P. verrucosum inoculated wheat kernels and OTA contaminated wheat kernels subjected to hyperspectral imaging provided different spectral patterns.

Identification and characterization of the polyketide synthase involved in ochratoxin A biosynthesis in Aspergillus carbonarius

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gallo, Antonia; Knox, Benjamin P.; Bruno, Kenneth S.

2014-06-02

Ochratoxin A (OTA) is a potent mycotoxin produced by Aspergillus and Penicillium species and is a common contaminant of a wide variety of food commodities, with Aspergillus carbonarius being the main producer of OTA contamination in grapes and wine. The molecular structure of OTA is composed of a dihydroisocoumarin ring linked to phenylalanine and, as shown in different producing fungal species, a polyketide synthase (PKS) is a component of the OTA biosynthetic pathway. Similar to observations in other filamentous ascomycetes, the genome sequence of A. carbonarius contains a large number of genes predicted to encode PKSs. In this work amore » pks gene identified within the putative OTA cluster of A. carbonarius, designated as AcOTApks, was inactivated and the resulting mutant strain was unable to produce OTA, confirming the role of AcOTApks in this biosynthetic pathway. AcOTApks protein is characteristic of the highly reduced (HR)-PKS family, and also contains a putative methyltransferase domain likely responsible for the addition of the methyl group to the OTA polyketide structure. AcOTApks is different from the ACpks protein that we previously described which showed an expression profile compatible with OTA production. We performed phylogenetic analyses of the β-ketosynthase and acyl-transferase domains of the OTA PKSs which had been identified and characterized in different OTA producing fungal species. The phylogenetic results were similar for both the two domains analyzed and showed that OTA PKS of A. carbonarius, Aspergillus niger, and Aspergillus ochraceus clustered in a monophyletic group with 100% bootstrap support suggesting a common origin, while the other OTA PKSs analyzed were phylogenetically distant. A qRT-PCR assay monitored AcOTApks expression during fungal growth and concomitant production of OTA by A. carbonarius in synthetic grape medium. A clear correlation between the expression profile of AcOTApks and kinetics of OTA production was observed with AcOTApks which reached its maximum level of transcription before OTA accumulation in mycelium reached its highest level, confirming the fact that gene transcription always precedes phenotypic production.« less

Effects of δ-tocotrienol on ochratoxin A-induced nephrotoxicity in rats.

PubMed

Damiano, Sara; Navas, Luigi; Lombari, Patrizia; Montagnaro, Serena; Forte, Iris M; Giordano, Antonio; Florio, Salvatore; Ciarcia, Roberto

2018-05-18

Ochratoxin A (OTA), is a natural contaminant of the food chain worldwide involved in the development of different type of cancers in animals and humans. Several studies suggested that oxidative damage might contribute to increase the cytotoxicity and carcinogenicity capabilities of OTA. The aim of this study was to evaluate the possible protective effect of δ-tocotrienol (Delta), a natural form of vitamin E, against OTA-induced nephrotoxicity. Male Sprague-Dawley rats were treated with OTA and/or Delta by gavage for 14 days. Our results shown that OTA treatment induced the increase of reactive oxigen species production correlated to a strong reduction of Glomerular Filtration Rate (GFR) and absoluted fluid reabsorption (Jv) with conseguent significant increase in blood pressure. Consistent, we noted in the kidney of rats treated with OTA, an increase in malondialdheyde and dihydroethidium production and a reduction of the activity of the catalase, superoxide dismutase, and glutathione peroxidase. Conversly, in the rat group subjected to the concomitant treatment OTA plus Delta, we observed the restored effect, compared the OTA treatment group, on blood pressure, GFR, Jv, and all activities of renal antioxidant enzymes. Finally, as far as concern the tissue damage induced by OTA and measured evaluating fibronectin protein levels, we observed that in OTA plus Delta group this effect is not restored. Our findings releval that a mechanism underlying the renal toxicity induced by OTA is the oxidative stress and provide a new rationale to use a Delta in order to protect, at least in part, against OTA-induced nephrotoxicity. © 2018 Wiley Periodicals, Inc.

Studies on carcinogenic and toxic effects of ochratoxin A in chicks.

PubMed

Stoev, Stoycho D

2010-04-01

Carcinogenic/toxic effects of ochratoxin A (OTA) in various internal organs of Plymouth Rock chicks were determined. The number of OTA-induced neoplasms was similar in chicks given 25 ppm L-β-phenylalanine (PHE) in addition to 5 ppm OTA compared to chicks given only 5 ppm OTA, which showed that PHE cannot be used as a real protector against the carcinogenic or toxic effects of OTA in chicks. OTA was found to provoke strong degenerative changes in liver and kidneys, degenerative changes and depletion of cells in lymphoid organs, oedematous and degenerative changes in the brain, muscular haemorrhages and fatty changes in the bone marrow. The target organs for carcinogenic effect of OTA in chicks were found to be kidneys and liver.

Label-Free G-Quadruplex Aptamer Fluorescence Assay for Ochratoxin A Using a Thioflavin T Probe.

PubMed

Wu, Kefeng; Ma, Changbei; Zhao, Han; He, Hailun; Chen, Hanchun

2018-05-12

Ochratoxin A (OTA) is one of the most common mycotoxins contaminating feed and foodstuffs. Therefore, a great deal of concern is associated with AFB1 toxicity. In this work, a fast and sensitive fluorescence aptamer biosensor has been proposed for the OTA assay. In the absence of OTA, the OTA aptamer can form a G-quadruplex structure with thioflavin T (ThT) dye, which results in increased fluorescence. After joining OTA, OTA aptamer combines with OTA and the G-quadruplex can be formed. Only faint fluorescence was finally observed when ThT weakly reacts with the quadruplex. Through this test method, the entire reaction and analysis process of OTA can be completed in 10 min. Under optimal experimental conditions (600 nM OTA-APT, 7 μM ThT, and 3 min incubation time), this proposed assay has a good limit of detection (LOD) of 0.4 ng/mL and shows a good linear relationship within the range of 1.2⁻200 ng/mL under the best experimental conditions. This method has a high specificity for OTA relative to Ochratoxin B (23%) and Aflatoxin B₁ (13%). In addition, the quantitative determination of this method in real samples has been validated using a sample of red wine supplemented with a range of OTA concentrations (1.2 ng/mL, 12 ng/mL, and 40 ng/mL) with recoveries of 96.5% to 107%.

Ochratoxin A induces rat renal carcinogenicity with limited induction of oxidative stress responses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qi, Xiaozhe; Yu, Tao; Zhu, Liye

Ochratoxin A (OTA) has displayed nephrotoxicity and renal carcinogenicity in mammals, however, no clear mechanisms have been identified detailing the relationship between oxidative stress and these toxicities. This study was performed to clarify the relationship between oxidative stress and the renal carcinogenicity induced by OTA. Rats were treated with 70 or 210 μg/kg b.w. OTA for 4 or 13 weeks. In the rats administrated with OTA for 13 weeks, the kidney was damaged seriously. Cytoplasmic vacuolization was observed in the outer stripe of the outer medulla. Karyomegaly was prominent in the tubular epithelium. Kidney injury molecule-1 (Kim-1) was detected inmore » the outer stripe of the outer medulla in both low- and high-dose groups. OTA increased the mRNA levels of clusterin in rat kidneys. Interestingly, OTA did not significantly alter the oxidative stress level in rat liver and kidney. Yet, some indications related to proliferation and carcinogenicity were observed. A dose-related increase in proliferating cell nuclear antigen (PCNA) was observed at 4 weeks in both liver and kidney, but at 13 weeks, only in the kidney. OTA down-regulated reactive oxygen species (ROS) and up-regulated vimentin and lipocalin 2 in rat kidney at 13 weeks. The p53 gene was decreased in both liver and kidney at 13 weeks. These results suggest that OTA caused apparent kidney damage within 13 weeks but exerted limited effect on oxidative stress parameters. It implies that cell proliferation is the proposed mode of action for OTA-induced renal carcinogenicity. - Highlights: • We studied OTA toxicities in both the rat liver and kidney for 13 weeks. • OTA exerts limited effects on oxidative stress in the rat liver and kidney. • OTA induced renal carcinogenicity resulting from cell proliferation.« less

The influence of ochratoxin A on DNA adduct formation by the carcinogen aristolochic acid in rats.

PubMed

Stiborová, Marie; Bárta, František; Levová, Kateřina; Hodek, Petr; Frei, Eva; Arlt, Volker M; Schmeiser, Heinz H

2015-11-01

Exposure to the plant nephrotoxin and carcinogen aristolochic acid (AA) leads to the development of AA nephropathy, Balkan endemic nephropathy (BEN) and upper urothelial carcinoma (UUC) in humans. Beside AA, exposure to ochratoxin A (OTA) was linked to BEN. Although OTA was rejected as a factor for BEN/UUC, there is still no information whether the development of AA-induced BEN/UUC is influenced by OTA exposure. Therefore, we studied the influence of OTA on the genotoxicity of AA (AA-DNA adduct formation) in vivo. AA-DNA adducts were formed in liver and kidney of rats treated with AA or AA combined with OTA, but no OTA-related DNA adducts were detectable in rats treated with OTA alone or OTA combined with AA. Compared to rats treated with AA alone, AA-DNA adduct levels were 5.4- and 1.6-fold higher in liver and kidney, respectively, of rats treated with AA combined with OTA. Although AA and OTA induced quinone oxidoreductase (NQO1) activating AA to DNA adducts, their combined treatment did not lead to either higher NQO1 enzyme activity or higher AA-DNA adduct levels in ex vivo incubations. Oxidation of AA I (8-methoxy-6-nitrophenanthro[3,4-d]-1,3-dioxole-5-carboxylic acid) to its detoxification metabolite, 8-hydroxyaristolochic acid, was lower in microsomes from rats treated with AA and OTA, and this was paralleled by lower activities of cytochromes P450 1A1/2 and/or 2C11 in these microsomes. Our results indicate that a decrease in AA detoxification after combined exposure to AA and OTA leads to an increase in AA-DNA adduct formation in liver and kidney of rats.

SeMet attenuates OTA-induced PCV2 replication promotion by inhibiting autophagy by activating the AKT/mTOR signaling pathway.

PubMed

Qian, Gang; Liu, Dandan; Hu, Junfa; Gan, Fang; Hou, Lili; Zhai, Nianhui; Chen, Xingxiang; Huang, Kehe

2018-02-13

Porcine circovirus type 2 (PCV2) is recognized as the causative agent of porcine circovirus-associated diseases. PCV2 replication could be promoted by low doses of ochratoxin A (OTA) as in our previous study and selenium has been shown to attenuate PCV2 replication. However, the underlying mechanism remains unclear. The aim of the study was to investigate the effects of selenomethionine (SeMet), the major component of organic selenium, on OTA-induced PCV2 replication promotion and its potential mechanism. The present study demonstrates that OTA could promote PCV2 replication as measured by cap protein expression, viral titer, viral DNA copies and the number of infected cells. In addition, OTA could activate autophagy as indicated by up-regulated light chain 3 (LC3)-II and autophagy-related protein 5 expressions and autophagosome formation. Further, OTA could down-regulate p-AKT and p-mTOR expressions and OTA-induced autophagy was inhibited when insulin was applied. SeMet at 2, 4 and 6 μM had significant inhibiting effects against OTA-induced PCV2 replication promotion. Furthermore, SeMet could attenuate OTA-induced autophagy and up-regulate OTA-induced p-AKT and p-mTOR expression inhibition. Rapamycin, an inhibitor of AKT/mTOR, could reverse the effects of SeMet on OTA-induced autophagy and the PCV2 replication promotion. In conclusion, SeMet could block OTA-induced PCV2 replication promotion by inhibiting autophagy by activating the AKT/mTOR pathway. Therefore, SeMet supplementation could be an effective prophylactic strategy against PCV2 infections and autophagy may be a potential marker to develop novel anti-PCV2 drugs.

Direct detection of OTA by impedimetric aptasensor based on modified polypyrrole-dendrimers.

PubMed

Mejri-Omrani, Nawel; Miodek, Anna; Zribi, Becem; Marrakchi, Mouna; Hamdi, Moktar; Marty, Jean-Louis; Korri-Youssoufi, Hafsa

2016-05-12

Ochratoxin A (OTA) is a carcinogenic mycotoxin that contaminates food such as cereals, wine and beer; therefore it represents a risk for human health. Consequently, the allowed concentration of OTA in food is regulated by governmental organizations and its detection is of major agronomical interest. In the current study we report the development of an electrochemical aptasensor able to directly detect trace OTA without any amplification procedure. This aptasensor was constructed by coating the surface of a gold electrode with a film layer of modified polypyrrole (PPy), which was thereafter covalently bound to polyamidoamine dendrimers of the fourth generation (PAMAM G4). Finally, DNA aptamers that specifically binds OTA were covalently bound to the PAMAM G4 providing the aptasensor, which was characterized by using both Atomic Force Microscopy (AFM) and Surface Plasmon Resonance (SPR) techniques. The study of OTA detection by the constructed electrochemical aptasensor was performed using Electrochemical Impedance Spectroscopy (EIS) and revealed that the presence of OTA led to the modification of the electrical properties of the PPy layer. These modifications could be assigned to conformational changes in the folding of the aptamers upon specific binding of OTA. The aptasensor had a dynamic range of up to 5 μg L(-1) of OTA and a detection limit of 2 ng L(-1) of OTA, which is below the OTA concentration allowed in food by the European regulations. The efficient detection of OTA by this electrochemical aptasensor provides an unforeseen platform that could be used for the detection of various small molecules through specific aptamer association. Copyright © 2016 Elsevier B.V. All rights reserved.

Ochratoxin A Concentrations in a Variety of Grain-Based and Non-Grain-Based Foods on the Canadian Retail Market from 2009 to 2014.

PubMed

Kolakowski, Beata; O'Rourke, Sarah M; Bietlot, Henri P; Kurz, Karl; Aweryn, Barbara

2016-12-01

The extent of ochratoxin A (OTA) contamination of domestically produced foods sold across Canada was determined from 2009 to 2014 with sampling and testing occurring each fiscal year. Cereal-based, fruit-based, and soy-based food samples (n = 6,857) were analyzed. Almost half of the samples (3,200; 47%) did not contain detectable concentrations of OTA. The remaining 3,657 samples contained OTA at 0.040 to 631 ng/g. Wheat, oats, milled products of other grains (such as rye and buckwheat), and to a lesser extent corn products and their derived foods were the most significant potential sources of OTA exposure for the Canadian population. Wine, grape juice, soy products, beer, dairy-based infant formula, and licorice candy were not significant contributors to OTA consumption. Spices had the highest OTA concentrations; but because so little is ingested, these foods are not considered to be a significant source of OTA. In contrast, infant formulas and cereals can be important dietary sources of OTA. Infant cereals containing oats and infant formulas containing soy had detectable concentrations of OTA, some of which exceeded the proposed Canadian guidelines. The prevalence and concentrations of OTA in major crops (wheat, corn, and oats) varied widely across years. Because these foods were purchased at retail stores, no information was available on the OTA concentrations in the raw materials, the storage conditions before purchase of the samples, or the origin of the ingredients (may include blends of raw materials from different years and/or different geographical regions of Canada); therefore, impact of these factors could not be assessed. Overall, 2.3% of the samples exceeded the proposed Canadian OTA regulatory limits and 2.7% exceeded the current European Union (EU) OTA regulatory limits. These results are consistent with a Health Canada exposure assessment published in 2010, despite the inclusion of a wider range of products and confirm the safety of foods widely available across Canada.

Mycotoxin production by different ochratoxigenic Aspergillus and Penicillium species on coffee- and wheat-based media.

PubMed

Muñoz, Katherine; Vega, Mario; Rios, Gisela; Geisen, Rolf; Degen, Gisela H

2011-11-01

Ochratoxin A (OTA) is one of the most widespread mycotoxins, and is produced by several Aspergillus or Penicillium species. Human exposure to OTA is mainly by intake of contaminated food, with cereal products, followed by coffee and red wine as the main sources of OTA. In this study, the OTA production of four ochratoxigenic fungi (two Aspergillus and two Penicillium species) was investigated in four different media, i.e. wheat and coffee model media as food-based media and two standard laboratory media (malt extract glucose agar, MEA and yeast extract sucrose agar, YES). Colony growth was documented and OTA concentrations in cultures were determined at day 2, 4 and 8 of incubation at 25°C by high-performance thin-layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC). OTA production clearly depended upon time of incubation, fungal species, and medium composition. On coffee based medium, moderate OTA levels were produced by A. ochraceus BFE635 (9.8 μg/g) and by A. niger BFE632 (10.6 μg/g) on day 8 of incubation. In wheat-based medium, these strains produced much more OTA than in coffee. The highest OTA concentration (83.8 μg/g on day 8) was formed by A. ochraceus BFE635 followed by the other Aspergillus niger BFE632 (49 μg/g). Lower OTA levels were produced by P. verrucosum BFE550 and P. nordicum BFE487, in both wheat and in YES medium, whilst OTA was hardly detectable in coffee and in MEA in case of P. nordicum. Colony growth of the tested strains on different media was not indicative of OTA production. Guttation droplets developed on wheat-based medium with the Aspergillus strains within a week, and this phenomenon coincided with the high OTA amounts formed by these species. Results from this study add to our knowledge on the behaviour of ochratoxigenic fungal species when cultured on food based media.

Ochratoxin a and mitotic disruption: mode of action analysis of renal tumor formation by ochratoxin A.

PubMed

Mally, Angela

2012-06-01

The mycotoxin and food contaminant ochratoxin A (OTA) is a potent renal carcinogen in rodents, but its mode of action (MoA) is still poorly defined. In 2006, the European Food Safety Authority concluded that there is a "lack of evidence for the existence of OTA-DNA adducts" and thus insufficient evidence to establish DNA reactivity as a MoA for tumor formation by OTA. In reviewing the available database on OTA toxicity, a MoA for renal carcinogenicity of OTA is developed that involves a combination of genetic instability and increased proliferative drive as consequences of OTA-mediated disruption of mitosis, whereby the organ- and site-specificity of tumor formation by OTA is determined by selective renal uptake of OTA into the proximal tubule epithelium. The proposed MoA is critically assessed with respect to concordance of dose-response of the suggested key events and tumor formation, their temporal association, consistency, and biological plausibility. Uncertainties, data gaps and needs for further research are highlighted.

Zinc protects HepG2 cells against the oxidative damage and DNA damage induced by ochratoxin A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Juanjuan; Zhang, Yu; Xu, Wentao, E-mail: xuwentaoboy@sina.com

Oxidative stress and DNA damage are the most studied mechanisms by which ochratoxin A (OTA) induces its toxic effects, which include nephrotoxicity, hepatotoxicity, immunotoxicity and genotoxicity. Zinc, which is an essential trace element, is considered a potential antioxidant. The aim of this paper was to investigate whether zinc supplement could inhibit OTA-induced oxidative damage and DNA damage in HepG2 cells and the mechanism of inhibition. The results indicated that that exposure of OTA decreased the intracellular zinc concentration; zinc supplement significantly reduced the OTA-induced production of reactive oxygen species (ROS) and decrease in superoxide dismutase (SOD) activity but did notmore » affect the OTA-induced decrease in the mitochondrial membrane potential (Δψ{sub m}). Meanwhile, the addition of the zinc chelator N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) strongly aggravated the OTA-induced oxidative damage. This study also demonstrated that zinc helped to maintain the integrity of DNA through the reduction of OTA-induced DNA strand breaks, 8-hydroxy-2′-deoxyguanosine (8-OHdG) formation and DNA hypomethylation. OTA increased the mRNA expression of metallothionein1-A (MT1A), metallothionein2-A (MT2A) and Cu/Zn superoxide dismutase (SOD1). Zinc supplement further enhanced the mRNA expression of MT1A and MT2A, but it had no effect on the mRNA expression of SOD1 and catalase (CAT). Zinc was for the first time proven to reduce the cytotoxicity of OTA through inhibiting the oxidative damage and DNA damage, and regulating the expression of zinc-associated genes. Thus, the addition of zinc can potentially be used to reduce the OTA toxicity of contaminated feeds. - Highlights: ► OTA decreased the intracellular zinc concentration. ► OTA induced the formation of 8-OHdG in HepG2 cells. ► It was testified for the first time that OTA induced DNA hypomethylation. ► Zinc protects against the oxidative damage and DNA damage induced by OTA in vitro.« less

Biodegradation of Ochratoxin A for Food and Feed Decontamination

PubMed Central

Abrunhosa, Luís; Paterson, Robert R. M.; Venâncio, Armando

2010-01-01

Ochratoxin A (OTA) is one of the most important mycotoxins that is found in food and feed products. It has proven toxic properties, being primarily known for its nephrotoxicity and carcinogenicity to certain animal species. OTA is produced by several species of Aspergillus and Penicillium that can be found in a wide variety of agricultural products, which makes the presence of OTA in these products common. Many countries have statutory limits for OTA, and concentrations need to be reduced to as low as technologically possible in food and feed. The most important measures to be taken to control OTA are preventive in order to avoid fungal growth and OTA production. However, these measures are difficult to implement in all cases with the consequence of OTA remaining in agricultural commodities. Remediation processes are often used to eliminate, reduce or avoid the toxic effects of OTA. Biological methods have been considered increasingly as an alternative to physical and chemical treatments. However, examples of practical applications are infrequent. This review will focus on the (i) known microorganisms and enzymes that are able to biodegrade OTA; (ii) mode of action of biodegradation and (iii) current applications. A critical discussion about the technical applicability of these strategies is presented. PMID:22069627

Detection of ochratoxin A (OTA) in coffee using chemiluminescence resonance energy transfer (CRET) aptasensor.

PubMed

Jo, Eun-Jung; Mun, Hyoyoung; Kim, Su-Ji; Shim, Won-Bo; Kim, Min-Gon

2016-03-01

We report a chemiluminescence resonance energy transfer (CRET) aptasensor for the detection of ochratoxin A (OTA) in roasted coffee beans. The aptamer sequences used in this study are 5'-DNAzyme-Linker-OTA aptamer-3'-dabcyl. Dabcyl at the end of the OTA aptamer region plays as a quencher in CRET aptasensor. When hemin and OTA are added, the dabcyl-labeled OTA aptamer approaches to the G-quadruplex-hemin complex by formation of the G-quadruplex-OTA complex. The G-quadruplex-hemin complexes possess horseradish peroxidase (HRP)-like activity, and therefore, the HRP-mimicking DNAzyme (HRPzyme) catalyzes peroxidation in the presence of luminol and H2O2. Resonance energy transfer between luminol (donor) and dabcyl (acceptor) enables quenching of chemiluminescence signals. The signal decreases with increasing the concentration of OTA within the range of 0.1-100ngmL(-1) (limit of detection 0.22ngmL(-1)), and the level of recovery of the respective 1ngmL(-1) and 10ngmL(-1) spiked coffee samples was 71.5% and 93.3%. These results demonstrated the potential of the proposed method for OTA analysis in diverse foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

Seed-borne fungi and ochratoxin A contamination of dry beans (Phaseolus vulgaris L.) in the Republic of Croatia.

PubMed

Domijan, A-M; Peraica, M; Zlender, V; Cvjetković, B; Jurjević, Z; Topolovec-Pintarić, S; Ivić, D

2005-03-01

The study was designed to identify seed-borne fungi on bean (Phaseolus vulgaris L.) crops grown in 13 counties of the Republic of Croatia and their association with ochratoxin A (OTA) production. Bean samples (N=45) were collected in Croatia in 2001 shortly after the harvest and were stored at -20 degrees C for mycological and mycotoxin analyses. The most common fungi isolated were Cladosporium spp. (98%) Alternaria spp. (75%), Aspergillus spp. (73%), Rhizopus spp. (73%), Penicillium spp. (69%), Fusarium spp. (38%), Botrytis spp. (27%), Trichothecium spp. (24%), and Chaetomium spp. (18%). OTA was found only in samples contaminated with Penicillium and Aspergillus spp. Using HPLC (detection limit 0.25 microg/kg), OTA was found in 17 out of 45 samples (38%), and the mean concentration in positive samples was 0.41+/-0.21 microg OTA/kg. Beans from south Croatia (Adriatic coast) were OTA-free and the least mould-infected, while the mean OTA concentration and mould infection of samples from other regions were similar. The OTA contamination of beans in our country is low. Although beans are not severely contaminated with OTA, their consumption may contribute to the exposure to OTA from other commodities.

Initial Spore Density Has an Influence on Ochratoxin A Content in Aspergillus ochraceus CGMCC 3.4412 in PDB and Its Interaction with Seeds.

PubMed

Li, Caiyan; Song, Yanmin; Xiong, Lu; Huang, Kunlun; Liang, Zhihong

2017-04-21

The morphology and secondary metabolism of Aspergillus spp. are associated with initial spore density (ISD). Fatty acids (FA) are involved in the biosynthesis of aflatoxins (AF) through Aspergillus quorum sensing (QS). Here, we studied how ochratoxin A (OTA) was regulated by spore density in Aspergillus ochraceus CGMCC 3.4412. The results contribute to understanding the role of spore density in morphogenesis, OTA biosynthesis, and host-pathogen interactions. When A. ochraceus was grown in Potato Dextrose Broth (PDB) media at different spore densities (from 10¹ to 10⁶ spores/mL), more OTA was produced when ISD were increased, but a higher level of ISD inhibited OTA biosynthesis. Seed infection studies showed that peanuts ( Arachis hypogaea ) and soybeans ( Glycine max ) with high FA content were more susceptible to OTA production when infected by A. ochraceus and reactive oxygen species (ROS)-induced OTA biosynthesis. These results suggested that FA was vital for OTA biosynthesis, and that oxidative stress was closely related to OTA biosynthesis in A. ochraceus .

Transfer of Ochratoxin A into Tea and Coffee Beverages

PubMed Central

Malir, Frantisek; Ostry, Vladimir; Pfohl-Leszkowicz, Annie; Toman, Jakub; Bazin, Ingrid; Roubal, Tomas

2014-01-01

Ochratoxin A (OTA) is nephrotoxic, hepatotoxic, immunotoxic, neurotoxic, reprotoxic, teratogenic, and carcinogenic (group 2B), being characterized by species and sex differences in sensitivity. Despite the fact that OTA is in some aspects a controversial topic, OTA is the most powerful renal carcinogen. The aim of this study was to make a small survey concerning OTA content in black tea, fruit tea, and ground roasted coffee, and to assess OTA transfer into beverages. OTA content was measured using a validated and accredited HPLC-FLD method with a limit of quantification (LOQ) of 0.35 ng/g. The OTA amount ranged from LOQ up to 250 ng/g in black tea and up to 104 ng/g in fruit tea. Black tea and fruit tea, naturally contaminated, were used to prepare tea infusions. The transfer from black tea to the infusion was 34.8% ± 1.3% and from fruit tea 4.1% ± 0.2%. Ground roasted coffee naturally contaminated at 0.92 ng/g was used to prepare seven kinds of coffee beverages. Depending on the type of process used, OTA transfer into coffee ranged from 22.3% to 66.1%. OTA intakes from fruit and black tea or coffee represent a non-negligible human source. PMID:25525684

Further aspects of ochratoxin A-cation interactions: complex formation with zinc ions and a novel analytical application of ochratoxin A-magnesium interaction in the HPLC-FLD system.

PubMed

Poór, Miklós; Kuzma, Mónika; Matisz, Gergely; Li, Yin; Perjési, Pál; Kunsági-Máté, Sándor; Kőszegi, Tamás

2014-04-10

Ochratoxin A (OTA) is a mycotoxin produced by different Aspergillus and Penicillium species. Since its mechanism of action is not fully understood yet, it is important to gain further insight into different interactions of OTA at the molecular level. OTA is found worldwide in many foods and drinks. Moreover, it can also be detected in human and animal tissues and body fluids, as well. Therefore, the development of highly sensitive quantitative methods for the determination of OTA is of utmost importance. OTA most likely forms complexes with divalent cations, both in cells and body fluids. In the present study, the OTA-zinc interaction was investigated and compared to OTA-magnesium complex formation using fluorescence spectroscopy and molecular modeling. Our results show that zinc(II) ion forms a two-fold higher stable complex with OTA than magnesium(II) ion. In addition, based on the enhanced fluorescence emission of OTA in its magnesium-bound form, a novel RP-HPLC-fluorescence detector (FLD) method was also established. Our results highlight that the application of magnesium chloride in alkaline eluents results in an approximately two-fold increase in sensitivity using the HPLC-FLD technique.

Impact of pH on the stability and the cross-reactivity of ochratoxin A and citrinin.

PubMed

Bazin, Ingrid; Faucet-Marquis, Virginie; Monje, Marie-Carmen; El Khoury, Micheline; Marty, Jean-Louis; Pfohl-Leszkowicz, Annie

2013-11-28

Mycotoxins are secondary metabolites produced by several fungi contaminating crops. In several countries, the maximum permitted levels of mycotoxins are found in foodstuffs and feedstuffs. The common strategy of mycotoxin analysis involves extraction, clean-up and quantification by chromatography. In this paper, we analyzed the reasons of underestimation of ochratoxin A (OTA) content in wine, and overestimation of OTA in wheat, depending on the pH of the clean-up step and the simultaneous presence of citrinin (CIT). We demonstrated that the increase of pH by adding polyethylene glycol (PEG) to wine led to an underestimation of OTA by conversion of OTA into open ring ochratoxin A OP-OA. In comparing three methods of extraction and clean-up for the determination of OTA and CIT in wheat--(i) an inter-laboratory validated method for OTA in cereals using immunoaffinity column clean-up (IAC) and extraction by acetonitrile/water; (ii) a validated method using IAC and extraction with 1% bicarbonate Na; and (iii) an in-house validated method based on acid liquid/liquid extraction--we observed an overestimation of OTA after immunoaffinity clean-up when CIT is also present in the sample, whereas an underestimation was observed when OTA was alone. Under neutral and alkaline conditions, CIT was partially recognized by OTA antibodies.

New Insight into the Ochratoxin A Biosynthetic Pathway through Deletion of a Nonribosomal Peptide Synthetase Gene in Aspergillus carbonarius

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gallo, A.; Bruno, K. S.; Solfrizzo, M.

2012-09-14

Ochratoxin A (OTA), a mycotoxin produced by Aspergillus and Penicillium species, is composed of a dihydroisocoumarin ring linked to phenylalanine and its biosynthetic pathway has not yet been completely elucidated. Most of the knowledge regarding the genetic and enzymatic aspects of OTA biosynthesis has been obtained in Penicillium species. In Aspergillus species only pks genes involved in the initial steps of the pathway have been partially characterized. In our study, the inactivation of a gene encoding a nonribosomal peptide synthetase in OTA producing A. carbonarius ITEM 5010 has removed the ability of the fungus to produce OTA. This is themore » first report on the involvement of an nrps gene product in OTA biosynthetic pathway in Aspergillus species. The absence of OTA and ochratoxin α-the isocoumaric derivative of OTA, and the concomitant increase of ochratoxin β- the dechloro analog of ochratoxin α- were observed in the liquid culture of transformed strain. The data provide the first evidence that the enzymatic step adding phenylalanine to polyketide dihydroisocoumarin precedes the chlorination step to form OTA in A. carbonarius, and that ochratoxin α is a product of hydrolysis of OTA, giving an interesting new insight in the biosynthetic pathway of the toxin.« less

Impact of pH on the Stability and the Cross-Reactivity of Ochratoxin A and Citrinin

PubMed Central

Bazin, Ingrid; Faucet-Marquis, Virginie; Monje, Marie-Carmen; El Khoury, Micheline; Marty, Jean-Louis; Pfohl-Leszkowicz, Annie

2013-01-01

Mycotoxins are secondary metabolites produced by several fungi contaminating crops. In several countries, the maximum permitted levels of mycotoxins are found in foodstuffs and feedstuffs. The common strategy of mycotoxin analysis involves extraction, clean-up and quantification by chromatography. In this paper, we analyzed the reasons of underestimation of ochratoxin A (OTA) content in wine, and overestimation of OTA in wheat, depending on the pH of the clean-up step and the simultaneous presence of citrinin (CIT). We demonstrated that the increase of pH by adding polyethylene glycol (PEG) to wine led to an underestimation of OTA by conversion of OTA into open ring ochratoxin A OP-OA. In comparing three methods of extraction and clean-up for the determination of OTA and CIT in wheat—(i) an inter-laboratory validated method for OTA in cereals using immunoaffinity column clean-up (IAC) and extraction by acetonitrile/water; (ii) a validated method using IAC and extraction with 1% bicarbonate Na; and (iii) an in-house validated method based on acid liquid/liquid extraction—we observed an overestimation of OTA after immunoaffinity clean-up when CIT is also present in the sample, whereas an underestimation was observed when OTA was alone. Under neutral and alkaline conditions, CIT was partially recognized by OTA antibodies. PMID:24287570

A Saccharomyces cerevisiae Wine Strain Inhibits Growth and Decreases Ochratoxin A Biosynthesis by Aspergillus carbonarius and Aspergillus ochraceus

PubMed Central

Cubaiu, Loredana; Abbas, Hamid; Dobson, Alan D. W.; Budroni, Marilena; Migheli, Quirico

2012-01-01

The aim of this study was to select wine yeast strains as biocontrol agents against fungal contaminants responsible for the accumulation of ochratoxin A (OTA) in grape and wine and to dissect the mechanism of OTA detoxification by a Saccharomyces cerevisiae strain (DISAABA1182), which had previously been reported to reduce OTA in a synthetic must. All of the yeast strains tested displayed an ability to inhibit the growth of Aspergillus carbonarius both in vivo and in vitro and addition of culture filtrates from the tested isolates led to complete inhibition of OTA production. S. cerevisiae DISAABA1182 was selected and further tested for its capacity to inhibit OTA production and pks (polyketide synthase) transcription in A. carbonarius and Aspergillus ochraceus in vitro. In order to dissect the mechanism of OTA detoxification, each of these two fungi was co-cultured with living yeast cells exposed to yeast crude or to autoclaved supernatant: S. cerevisiae DISAABA1182 was found to inhibit mycelial growth and OTA production in both Aspergilli when co-cultured in the OTA-inducing YES medium. Moreover, a decrease in pks transcription was observed in the presence of living cells of S. cerevisiae DISAABA1182 or its supernatant, while no effects were observed on transcription of either of the constitutively expressed calmodulin and β-tubulin genes. This suggests that transcriptional regulation of OTA biosynthetic genes takes place during the interaction between DISAABA1182 and OTA-producing Aspergilli. PMID:23223175

Managing ochratoxin A risk in the grape-wine food chain.

PubMed

Visconti, Angelo; Perrone, Giancarlo; Cozzi, Giuseppe; Solfrizzo, Michele

2008-02-01

The main source of ochratoxin A (OTA) in the wine food chain is the infection of grapes by "black aspergilli" in the field. OTA-producing black aspergilli include principally Aspergillus carbonarius, followed by A. niger and possibly A. tubingensis. They are opportunistic fungi that develop particularly on damaged berries at ripening, although they may occur and form OTA on grapes from veraison to harvest. Climatic conditions (high humidity and temperature) and geographical location are important factors favouring OTA accumulation in grape berries. The severity of aspergillus rot is influenced by excessive irrigation and rainfall prior to harvest, which causes berry splitting. In addition, berry wounds caused by insect attack provide preferential entries for black aspergilli. High OTA levels occur in grapes severely damaged by the grape moth, Lobesia botrana, particularly in Mediterranean areas. Some grape varieties display greater susceptibility to aspergillus rot due to intrinsic genetic characteristics and bunch conformation (i.e. compact>sparse). Control measures for toxigenic mycoflora in the vineyards must consider these critical control points. Proper fungicidal and insecticidal treatments can reduce OTA contamination. Nevertheless, knowledge about the fate of OTA and its distribution in wine and winery by-products is important to manage OTA risk in contaminated stock. In our wine-making experiments, only 4% of the OTA present in grapes remained in the wine--the majority is retained in pressed grape pomaces. OTA concentration remained unchanged in wine after a 1-year aging as well as in all liquid fractions collected during vinification (i.e. must, free run wine, and wine after first and second decantation). Activated carbon can reduce OTA levels in wine but negatively affects wine quality.

The role of oxidative stress in the ochratoxin A-mediated toxicity in proximal tubular cells.

PubMed

Schaaf, G J; Nijmeijer, S M; Maas, R F M; Roestenberg, P; de Groene, E M; Fink-Gremmels, J

2002-11-20

Balkan endemic nephropathy (BEN), a disease characterized by progressive renal fibrosis in human patients, has been associated with exposure to ochratoxin A (OTA). This mycotoxin is a frequent contaminant of human and animal food products, and is toxic to all animal species tested. OTA predominantly affects the kidney and is known to accumulate in the proximal tubule (PT). The induction of oxidative stress is implicated in the toxicity of this mycotoxin. In the present study, primary rat PT cells and LLC-PK(1) cells, which express characteristics of the PT, were used to investigate the OTA-mediated oxidative stress response. OTA exposure of these cells resulted in a concentration-dependent elevation of reactive oxygen species (ROS) levels, depletion of cellular glutathione (GSH) levels and an increase in the formation of 8-oxoguanine. The OTA-induced ROS response was significantly reduced following treatment with alpha-tocopherol (TOCO). However, this chain-braking anti-oxidant did not reduce the cytotoxicity of OTA and was unable to prevent the depletion of total GSH levels in OTA-exposed cells. In contrast, pre-incubation of the cell with N-acetyl-L-cysteine (NAC) completely prevented the OTA-induced increase in ROS levels as well as the formation of 8-oxoguanine and completely protected against the cytotoxicity of OTA. In addition, NAC treatment also limited the GSH depletion in OTA-exposed PT- and LLC-PK(1) cells. From these data, we conclude that oxidative stress contributes to the tubular toxicity of OTA. Subsequently, cellular GSH levels play a pivotal role in limiting the short-term toxicity of this mycotoxin in renal tubular cells.

Cytotoxic Effects of Ochratoxin A in Neuro-2a Cells: Role of Oxidative Stress Evidenced by N-acetylcysteine.

PubMed

Bhat, Pratiksha V; Pandareesh; Khanum, Farhath; Tamatam, Anand

2016-01-01

Ochratoxin-A (OTA), is toxic secondary metabolite and is found to be a source of vast range of toxic effects like hepatotoxicity, nephrotoxicity. However, the information available currently regarding neurotoxic effects exerted by OTA is scanty. Hence, the present study was aimed to evaluate the neurotoxic effects of OTA and the possible mechanisms of toxicity as well as the role of cytotoxic oxidative stress on neuronal (Neuro-2a) cell line was evaluated in vitro. Results of the MTT and LDH assay showed that, OTA induced dose-dependent cell death in Neuro-2a cells and EC50 value was determined as 500 nM. OTA induced high levels of reactive oxygen species (ROS) and elevated levels of malondialdehyde, also loss of mitochondrial membrane potential was observed in a dose depended manner. Effects of OTA on ROS induced chromosomal DNA damage was assessed by Comet assay and plasmid DNA damage assay in which increase in DNA damage was observed in Neuro-2a cells by increasing the OTA concentration. Further western blotting analysis of OTA treated Neuro-2a cells indicated elevated expression levels of c-Jun, JNK3 and cleaved caspase-3 leading to apoptotic cell death. Other hand realtime-Q-PCR analysis clearly indicates the suppressed expression of neuronal biomarker genes including AChE, BDNF, TH and NOS2. Further N-acetylcysteine (NAC) pretreatment to Neuro-2a cells followed by OTA treatment clearly evidenced that, the significant reversal of toxic effects exerted by OTA on Neuro-2a cells. In the present study, results illustrate that ROS a principle event in oxidative stress was elevated by OTA toxicity in Neuro-2a cells. However, further in vivo, animal studies are in need to conclude the present study reports and the use of NAC as a remedy for OTA induced neuronal stress.

[Toxicological characteristics of Ochratoxin A and its impact on male reproduction].

PubMed

Zhang, Tian-Yu; Zhao, Yong; Li, Lan; Shen, Wei

2017-08-01

Ochratoxin A (OTA) is found not only nephrotoxic, teratogenic, neurotoxic, and immunotoxic, but also reprotoxic for human and animals. In the recent decade, more attention has been paid to the impact of OTA on human reproduction and the studies of its underlying mechanisms. Many studies show that OTA affects the function of the reproductive system by acting as an endocrine disrupter and, as a testicular toxin, decreases sperm quality and even induces testis cancer. This review summarizes the toxicological characteristics and toxicokinetic process of OTA as well as recent progress in the studies of various toxic effects of OTA and their underlying mechanisms, hoping to call the attention from more people to the toxicity of OTA to male reproductive health.

International Competitiveness in Electronics.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. Office of Technology Assessment.

This assessment continues the Office of Technology Assessment's (OTA) exploration of the meaning of industrial policy in the United States context, while also examining the industrial policies of several U.S. economic rivals. The major focus is on electronics, an area which virtually defines "high technology" of the 1980's. The…

Ultrasensitive electrochemiluminescent aptasensor for ochratoxin A detection with the loop-mediated isothermal amplification.

PubMed

Yuan, Yali; Wei, Shiqiang; Liu, Guangpeng; Xie, Shunbi; Chai, Yaqin; Yuan, Ruo

2014-02-06

In this study, we for the first time presented an efficient, accurate, rapid, simple and ultrasensitive detection system for small molecule ochratoxin A (OTA) by using the integration of loop-mediated isothermal amplification (LAMP) technique and subsequently direct readout of LAMP amplicons with a signal-on electrochemiluminescent (ECL) system. Firstly, the dsDNA composed by OTA aptamer and its capture DNA were immobilized on the electrode. After the target recognition, the OTA aptamer bond with target OTA and subsequently left off the electrode, which effectively decreased the immobilization amount of OTA aptamer on electrode. Then, the remaining OTA aptamers on the electrode served as inner primer to initiate the LAMP reaction. Interestingly, the LAMP amplification was detected by monitoring the intercalation of DNA-binding Ru(phen)3(2+) ECL indictors into newly formed amplicons with a set of integrated electrodes. The ECL indictor Ru(phen)3(2+) binding to amplicons caused the reduction of the ECL intensity due to the slow diffusion of Ru(phen)3(2+)-amplicons complex to the electrode surface. Therefore, the presence of more OTA was expected to lead to the release of more OTA aptamer, which meant less OTA aptamer remained on electrode for producing LAMP amplicons, resulting in less Ru(phen)3(2+) interlaced into the formed amplicons within a fixed Ru(phen)3(2+) amount with an obviously increased ECL signal input. As a result, a detection limit as low as 10 fM for OTA was achieved. The aptasensor also has good reproducibility and stability. Copyright © 2013 Elsevier B.V. All rights reserved.

OTA-Grapes: A Mechanistic Model to Predict Ochratoxin A Risk in Grapes, a Step beyond the Systems Approach

PubMed Central

Battilani, Paola; Camardo Leggieri, Marco

2015-01-01

Ochratoxin A (OTA) is a fungal metabolite dangerous for human and animal health due to its nephrotoxic, immunotoxic, mutagenic, teratogenic and carcinogenic effects, classified by the International Agency for Research on Cancer in group 2B, possible human carcinogen. This toxin has been stated as a wine contaminant since 1996. The aim of this study was to develop a conceptual model for the dynamic simulation of the A. carbonarius life cycle in grapes along the growing season, including OTA production in berries. Functions describing the role of weather parameters in each step of the infection cycle were developed and organized in a prototype model called OTA-grapes. Modelling the influence of temperature on OTA production, it emerged that fungal strains can be shared in two different clusters, based on the dynamic of OTA production and according to the optimal temperature. Therefore, two functions were developed, and based on statistical data analysis, it was assumed that the two types of strains contribute equally to the population. Model validation was not possible because of poor OTA contamination data, but relevant differences in OTA-I, the output index of the model, were noticed between low and high risk areas. To our knowledge, this is the first attempt to assess/model A. carbonarius in order to predict the risk of OTA contamination in grapes. PMID:26258791

Occurrence of ochratoxin a contamination and detection of ochratoxigenic Aspergillus species in retail samples of dried fruits and nuts.

PubMed

Palumbo, Jeffrey D; O'Keeffe, Teresa L; Ho, Yvonne S; Santillan, Carlo J

2015-04-01

Ochratoxin A (OTA) is a mycotoxin produced by several species of Aspergillus and Penicillium and is a potential contaminant of a wide variety of food products. To determine the incidence of OTA contamination in dried fruits and tree nuts, retail packaged and bulk raisins, dates, figs, prunes, almonds, pistachios, and walnuts were collected from small and large supermarkets in seven areas of the United States between 2012 and 2014. Of the 665 samples analyzed, OTA was detected in 48 raisin samples, 4 fig samples, 4 pistachio samples, and 1 date sample. OTA contamination levels ranged from 0.28 to 15.34 ng/g in dried fruits and 1.87 to 890 ng/g in pistachios; two raisin samples and one pistachio sample exceeded the European Union regulatory limit of 10 ng/g. PCR detection of potential OTA-producing Aspergillus species revealed the presence of A. niger, A. welwitschiae, and A. carbonarius in 20, 7, and 7 of the 57 OTA-contaminated samples, respectively. However, OTA-producing A. carbonarius was isolated from only one raisin sample, and no other OTA-producing Aspergillus species were found. These results suggest that raisins are more frequently contaminated with low levels of OTA than are other dried fruits and nuts and that Aspergillus species are the likely source of that contamination.

Producers and Important Dietary Sources of Ochratoxin A and Citrinin

PubMed Central

Ostry, Vladimir; Malir, Frantisek; Ruprich, Jiri

2013-01-01

Ochratoxin A (OTA) is a very important mycotoxin, and its research is focused right now on the new findings of OTA, like being a complete carcinogen, information about OTA producers and new exposure sources of OTA. Citrinin (CIT) is another important mycotoxin, too, and its research turns towards nephrotoxicity. Both additive and synergistic effects have been described in combination with OTA. OTA is produced in foodstuffs by Aspergillus Section Circumdati (Aspergillus ochraceus, A. westerdijkiae, A. steynii) and Aspergillus Section Nigri (Aspergillus carbonarius, A. foetidus, A. lacticoffeatus, A. niger, A. sclerotioniger, A. tubingensis), mostly in subtropical and tropical areas. OTA is produced in foodstuffs by Penicillium verrucosum and P. nordicum, notably in temperate and colder zones. CIT is produced in foodstuffs by Monascus species (Monascus purpureus, M. ruber) and Penicillium species (Penicillium citrinum, P. expansum, P. radicicola, P. verrucosum). OTA was frequently found in foodstuffs of both plant origin (e.g., cereal products, coffee, vegetable, liquorice, raisins, wine) and animal origin (e.g., pork/poultry). CIT was also found in foodstuffs of vegetable origin (e.g., cereals, pomaceous fruits, black olive, roasted nuts, spices), food supplements based on rice fermented with red microfungi Monascus purpureus and in foodstuffs of animal origin (e.g., cheese). PMID:24048364

Screening and Identification of Novel Ochratoxin A-Producing Fungi from Grapes

PubMed Central

Zhang, Xiaoyun; Li, Yulin; Wang, Haiying; Gu, Xiangyu; Zheng, Xiangfeng; Wang, Yun; Diao, Junwei; Peng, Yaping; Zhang, Hongyin

2016-01-01

Ochratoxin A (OTA) contamination has been established as a world-wide problem. In this study, the strains with the ability of OTA production were screened by analyzing the green fluorescence of the isolates colonies from the grapes in Zhenjiang with 365 nm UV light and confirmed by HPLC with fluorescent detection (HPLC-FLD). The results showed that seven isolates acquired the characteristic of the fluorescence, of which only five showed the ability of OTA production as confirmed by HPLC-FLD analysis. The five OTA-producing strains were identified based on comparative sequence analysis of three conserved genes (ITS, BenA and RPB2) of the strains, and they are Talaromyces rugulosus (O1 and Q3), Penicillium commune (V5-1), Penicillium rubens (MQ-5) and Aspergillus aculeatus (MB1-1). There are two Penicillium species of the five OTA-producing strains and our study is the first to report that P. rubens, T. rugulosus and A. aculeatus can produce OTA. This work would contribute to comprehensively understanding the fungi with an OTA-producing ability in grapes before harvest and then take effective measures to prevent OTA production. PMID:27845758

Fluorometric aptamer based assay for ochratoxin A based on the use of exonuclease III.

PubMed

Liu, Renjie; Wu, Hua; Lv, Lei; Kang, Xiaojiao; Cui, Chengbi; Feng, Jin; Guo, Zhijun

2018-04-14

This study describes an aptamer based assay for the mycotoxin ochratoxin A (OTA). The method is based on the use of an OTA-specific aptamer, exonuclease (Exo) III, SYBR Gold as a fluorescent probe, and a complementary strand that specifically combines with the aptamer. In the presence of OTA, the aptamer and OTA hybridize, thereby resulting in the formation of ssDNA, which is not digested by Exo III. Intense fluorescence is observed after addition of SYBR Gold (best measured at excitation/emission wavelengths of 495/540 nm). Fluorescence increases linearly with the log of the OTA concentration in the range from 8 to 1000 ng·mL -1 . The detection limit is 4.7 ng·mL -1 . The assay was applied to the determination of OTA in diluted [2%(v/v)] red wine, and recoveries and RSDs ranged between 93.5% and 113.8%, and between 3.2% and 5.7%, respectively. Graphical abstract In the presence of ochratoxin A (OTA), specific combinations of aptamer and OTA may occur and result in DNA double strands being untied, which avoids being digested by Exo III. Intense fluorescence is observed after SYBR Gold addition.

Ochratoxin A reduction in meat sausages using processing methods practiced in households.

PubMed

Pleadin, Jelka; Perši, Nina; Kovačević, Dragan; Vulić, Ana; Frece, Jadranka; Markov, Ksenija

2014-01-01

The aim of this study was to investigate the possibilities of ochratoxin A (OTA) reduction in home-made meat products. Meat sausages (n = 50) produced from raw materials coming from pigs exposed to OTA-contaminated feed, were subject to common heat processes practiced in households (cooking, frying and baking). Concentrations of OTA in pre- and post-processed products were quantified using a validated immunoassay method, enzyme-linked immunosorbent assay, and confirmed using a high-performance liquid chromatography with fluorescence detection. In line with the differences in recipes used and the degree of OTA accumulation in raw materials, OTA concentrations established in Mediterranean and roast sausages were lower than those found in liver and blood sausages. Baking of contaminated sausages at the temperatures of 190-220°C (for 60 min) resulted in significant reduction of OTA levels (75.8%), while 30-min cooking (at 100°C) and frying (at 170°C) proved to be significantly less effective (e.g. yielding OTA reductions of 7.4% and 12.6%, respectively). The results pointed out that despite high OTA stability, heat processes are capable of reducing its concentration in home-made meat products, depending on the processing modality used.

Novel highly-performing immunosensor-based strategy for ochratoxin A detection in wine samples.

PubMed

Prieto-Simón, Beatriz; Campàs, Mònica; Marty, Jean-Louis; Noguer, Thierry

2008-02-28

The increasing concern about ochratoxin A (OTA) contamination of different food and feedstuffs demands high-performing detection techniques for quality assessment. Two indirect competitive enzyme-linked immunosorbent assay (ELISA) strategies were investigated for the development of OTA electrochemical immunosensors based on different OTA immobilisation procedures. Immunosensors based on avidin/biotin-OTA showed enhanced performance characteristics compared to those based on the adsorption of bovine serum albumin (BSA)-OTA conjugate. Performance of polyclonal (PAb) and monoclonal (MAb) antibodies against OTA was compared, showing at least one-order of magnitude lower IC(50) values when working with MAb. Alkaline phosphatase (ALP)- and horseradish peroxidase (HRP)-labelled secondary antibodies were evaluated. Both conjugates led to similar results when working with OTA standard solutions in buffer. However, whereas electroactive interferences present in spiked wine samples did not affect HRP-labelled immunosensors (4% slope deviation), they were likely oxidised at 0.225 V versus Ag/AgCl, the working potential for ALP-labelled immunosensors (25% slope deviation). Considering 80% of antibody binding as the limit of detection, values of 0.7 and 0.3 ng/mL for HRP- and ALP-labelled immunosensors respectively, validate these immunosensors as useful screening tools to assess OTA levels in wine.

Ochratoxin A Producing Species in the Genus Penicillium

PubMed Central

Cabañes, Francisco Javier; Bragulat, Maria Rosa; Castellá, Gemma

2010-01-01

Ochratoxin A (OTA) producing fungi are members of the genera Aspergillus and Penicillium. Nowadays, there are about 20 species accepted as OTA producers, which are distributed in three phylogenetically related but distinct groups of aspergilli of the subgenus Circumdati and only in two species of the subgenus Penicillium. At the moment, P. verrucosum and P. nordicum are the only OTA producing species accepted in the genus Penicillium. However, during the last century, OTA producers in this genus were classified as P. viridicatum for many years. At present, only some OTA producing species are known to be a potential source of OTA contamination of cereals and certain common foods and beverages such as bread, beer, coffee, dried fruits, grape juice and wine among others. Penicillium verrucosum is the major producer of OTA in cereals such as wheat and barley in temperate and cold climates. Penicillium verrucosum and P. nordicum can be recovered from some dry-cured meat products and some cheeses. PMID:22069629

Mycotoxins as human carcinogens-the IARC Monographs classification.

PubMed

Ostry, Vladimir; Malir, Frantisek; Toman, Jakub; Grosse, Yann

2017-02-01

Humans are constantly exposed to mycotoxins (e.g. aflatoxins, ochratoxins), mainly via food intake of plant and animal origin. The health risks stemming from mycotoxins may result from their toxicity, in particular their carcinogenicity. In order to prevent these risks, the International Agency for Research on Cancer (IARC) in Lyon (France)-through its IARC Monographs programme-has performed the carcinogenic hazard assessment of some mycotoxins in humans, on the basis of epidemiological data, studies of cancer in experimental animals and mechanistic studies. The present article summarizes the carcinogenic hazard assessments of those mycotoxins, especially aflatoxins (aflatoxin B 1 , B 2 , G 1 , G 2 and M 1 ), fumonisins (fumonisin B 1 and B 2 ) and ochratoxin A (OTA). New information regarding the genotoxicity of OTA (formation of OTA-DNA adducts), the role of OTA in oxidative stress and the identification of epigenetic factors involved in OTA carcinogenesis-should they indeed provide strong evidence that OTA carcinogenicity is mediated by a mechanism that also operates in humans-could lead to the reclassification of OTA.

Occurrence of ochratoxin A in wine and beer samples from China.

PubMed

Wu, Jianwei; Tan, Yinfeng; Wang, Yuqi; Xu, Rong

2011-01-01

A total of 125 wine and beer samples, including 42 white, 63 red wine and 20 beer samples, originating from several areas of China were analyzed for ochratoxin A (OTA). An analytical method based on immunoaffinity column (IAC) for clean-up and high performance liquid chromatography with fluorescence detection (HPLC-FD) was used to determine OTA. Positive results were further confirmed by LC-MS-MS. OTA was detected in 22 (17.6%) samples at levels of 0.02-1.18 ng/ml, which were below the EU maximum limit. The mean OTA concentration in red wine was slightly higher than in white wine. This study showed that OTA occurs in wine and beer in China but at levels that pose no danger of significant human exposure to OTA from this source.

Assessment and characterisation of yeast-based products intended to mitigate ochratoxin exposure using in vitro and in vivo models.

PubMed

Pfohl-Leszkowicz, A; Hadjeba-Medjdoub, K; Ballet, N; Schrickx, J; Fink-Gremmels, J

2015-01-01

The aim of this paper was to evaluate the capacity of several yeast-based products, derived from baker's and brewer's yeasts, to sequester the mycotoxin ochratoxin A (OTA) and to decrease its rate of absorption and DNA adduct formation in vivo. The experimental protocol included in vitro binding studies using isotherm models, in vivo chicken experiments, in which the serum and tissue concentrations of OTA were analysed in the absence and presence of the test compounds, and the profile of OTA-derived metabolites and their associated DNA adducts were determined. Additionally in vitro cell culture studies (HK2 cells) were applied to assess further the effects for yeast cell product enriched with glutathione (GSH) or selenium. Results of the in vitro binding assay in a buffer system indicated the ability of the yeast-based products, as sequester of OTA, albeit at a different level. In the in vitro experiments in chickens, decreased serum and tissue concentrations of treated animals confirmed that yeast-based products are able to prevent the absorption of OTA. A comparison of the binding affinity in a standard in vitro binding assay with the results obtained in an in vivo chicken experiment, however, showed a poor correlation and resulted in a different ranking of the products. More importantly, we could show that yeast-based products actively modulate the biotransformation of OTA in vivo as well as in vitro in a cell culture model. This effect seems to be attributable to residual enzymatic activities in the yeast-based products. An enrichment of yeast cell wall products with GSH or selenium further modulated the profile of the generated OTA metabolites and the associated pattern of OTA-induced DNA adducts by increasing the conversion of OTA into less toxic metabolites such as OTA, OTB and 4-OH-OTA. A reduced absorption and DNA adduct formation was particularly observed with GSH-enriched yeast, whereas selenium-enriched yeasts could counteract the OTA-induced decrease in cell viability, but at the same time increased the OTA-DNA adducts formation. These findings indicate the need for an in-depth characterisation of yeast-based products used as mycotoxin-mitigating feed additives, in in vivo models with target animal species taking into account not only their ability to sequester toxins in the gastrointestinal tract but also their potential effects on the biotransformation of mycotoxins.

Exposure of infants to ochratoxin A with breast milk.

PubMed

Muñoz, K; Blaszkewicz, M; Campos, V; Vega, M; Degen, G H

2014-03-01

The nephrotoxic and carcinogenic mycotoxin ochratoxin A (OTA) is a worldwide contaminant in food commodities and also found frequently in human biological fluids. Dietary contaminants ingested by nursing mothers can appear in breast milk. But the rate of lactational transfer of OTA has not been investigated so far at various stages of breastfeeding. Therefore, and to investigate OTA exposure of Chilean infants, we conducted a longitudinally designed study in mother-child pairs (n = 21) with parallel collection of maternal blood, milk and of infant urine samples over a period of up to 6 months. Validated analytical methods were applied to determine OTA concentrations in all biological samples (n = 134). OTA was detected in almost all maternal blood plasma, at concentrations ranging between 72 and 639 ng/L. The OTA concentrations in breast milk were on average one quarter of those measured in plasma (M/P ratio 0.25). Interestingly, a higher fraction of circulating OTA was excreted in colostrum (M/P 0.4) than with mature milk (M/P ≤ 0.2). Infants exposure was calculated as daily intake from our new data for OTA levels in breast milk, and taking into account milk consumption and body weight as additional variables: Chilean infants have an average intake of 12.7 ± 9.1 ng/kg bw during the first 6 days after delivery while intake with mature milk results in average values close to 5.0 ng/kg bw/day. Their OTA exposure is discussed in the context of tolerable intake values suggested by different scientific bodies. Moreover, the study design enabled a comparison of OTA intake and infant urine concentrations over the breastfeeding period. The statistical analysis of n = 27 paired values showed a good correlation (r = 0.57) for this type of studies and thereby confirms that urinary OTA analysis in infants is a valid biomarker of exposure.

Detoxification of zearalenone and ochratoxin A by ozone and quality evaluation of ozonised corn.

PubMed

Qi, Lijun; Li, Yulin; Luo, Xiaohu; Wang, Ren; Zheng, Ruihang; Wang, Li; Li, Yongfu; Yang, Dan; Fang, Wenmiao; Chen, Zhengxing

2016-11-01

Zearalenone (ZEN) and ochratoxin A (OTA) are secondary toxic metabolites of fungi that can contaminate a wide range of food and feedstuff. In this study, the effects of ozone treatment on ZEN and OTA and the quality of ozonised corn are investigated. Ozone significantly affects ZEN and OTA solutions. ZEN was undetectable 5 s after being treated with 10 mg l -1 ozone. However, OTA was resistant to ozonation with a degradation rate of 65.4% after 120 s of treatment. Moreover, ZEN and OTA solutions were difficult to degrade after being dried by a nitrogen stream. Results showed that ozone effectively degraded ZEN and OTA in corn. The degradation rates of ZEN and OTA in corn increased with ozone concentration and treatment time. The degradation of ZEN and OTA at different ozone concentrations appropriately conformed to first-order kinetics with an R 2 value > 0.8749. Furthermore, under the same conditions, corn with increased moisture content (MC) (19.6%) was more sensitive to ozone than corn with a low MC (14.1%). When treated with 100 mg l -1 ozone for 180 min, ZEN and OTA in corn with 19.6% MC decreased by 90.7% and 70.7%, respectively. To evaluate the quality of ozonised corn, subsequent quality experiments were conducted using corn samples treated at different times with 100 mg l -1 ozone. The MC of corn decreased after ozone treatment. The whiteness and yellowness of the corn increased and decreased with increasing time, respectively. The fatty acid value of the corn increased significantly (p ≤ 0.05) after 180 min of treatment. This study verified that ozone can effectively degrade ZEN and OTA in corn, but slightly affected corn quality.

Design of a sampling plan to detect ochratoxin A in green coffee.

PubMed

Vargas, E A; Whitaker, T B; Dos Santos, E A; Slate, A B; Lima, F B; Franca, R C A

2006-01-01

The establishment of maximum limits for ochratoxin A (OTA) in coffee by importing countries requires that coffee-producing countries develop scientifically based sampling plans to assess OTA contents in lots of green coffee before coffee enters the market thus reducing consumer exposure to OTA, minimizing the number of lots rejected, and reducing financial loss for producing countries. A study was carried out to design an official sampling plan to determine OTA in green coffee produced in Brazil. Twenty-five lots of green coffee (type 7 - approximately 160 defects) were sampled according to an experimental protocol where 16 test samples were taken from each lot (total of 16 kg) resulting in a total of 800 OTA analyses. The total, sampling, sample preparation, and analytical variances were 10.75 (CV = 65.6%), 7.80 (CV = 55.8%), 2.84 (CV = 33.7%), and 0.11 (CV = 6.6%), respectively, assuming a regulatory limit of 5 microg kg(-1) OTA and using a 1 kg sample, Romer RAS mill, 25 g sub-samples, and high performance liquid chromatography. The observed OTA distribution among the 16 OTA sample results was compared to several theoretical distributions. The 2 parameter-log normal distribution was selected to model OTA test results for green coffee as it gave the best fit across all 25 lot distributions. Specific computer software was developed using the variance and distribution information to predict the probability of accepting or rejecting coffee lots at specific OTA concentrations. The acceptation probability was used to compute an operating characteristic (OC) curve specific to a sampling plan design. The OC curve was used to predict the rejection of good lots (sellers' or exporters' risk) and the acceptance of bad lots (buyers' or importers' risk).

Development of sandwich dot-ELISA for specific detection of Ochratoxin A and its application on to contaminated cereal grains originating from India

PubMed Central

Venkataramana, M.; Rashmi, R.; Uppalapati, Siva R.; Chandranayaka, S.; Balakrishna, K.; Radhika, M.; Gupta, Vijai K.; Batra, H. V.

2015-01-01

In the present study, generation and characterization of a highly specific monoclonal antibody (mAb) against Ochratoxin A (OTA) was undertaken. The generated mAb was further used to develop a simple, fast, and sensitive sandwich dot-ELISA (s-dot ELISA) method for detection of OTA from contaminated food grain samples. The limit of detection (LOD) of the developed enzyme-linked immunosorbent assay (ELISA) method was determined as 5.0 ng/mL of OTA. Developed method was more specific toward OTA and no cross reactivity was observed with the other tested mycotoxins such as deoxynivalenol, fumonisin B1, or aflatoxin B1. To assess the utility and reliability of the developed method, several field samples of maize, wheat and rice (n = 195) collected from different geographical regions of southern Karnataka region of India were evaluated for the OTA occurrence. Seventy two out of 195 samples (19 maize, 38 wheat, and 15 rice) were found to be contaminated by OTA by s-dot ELISA. The assay results were further co-evaluated with conventional analytical high-performance liquid chromatography (HPLC) method. Results of the s-dot ELISA are in concordance with HPLC except for three samples that were negative for OTA presence by s-dot ELISA but found positive by HPLC. Although positive by HPLC, the amount of OTA in the three samples was found to be lesser than the accepted levels (>5 μg/kg) of OTA presence in cereals. Therefore, in conclusion, the developed s-dot ELISA is a better alternative for routine cereal based food and feed analysis in diagnostic labs to check the presence of OTA over existing conventional culture based, tedious analytical methods. PMID:26074899

Occurrence of Ochratoxin A in Grape Juice of Iran

PubMed Central

Yusefi, Jamal; Valaee, Mehran; Nazari, Firouzeh; Maleki, Javad; Mottaghianpour, Ehsan; Khosrokhavar, Roya; Hosseini, Mir-Jamal

2018-01-01

Ochratoxin A (OTA) is one of the most important mycotoxins that contaminate a broad range of agricultural and food products. In this study, the occurrence of OTA in available brands of grape juice in Iran purchased from retail outlets or producer were determined for the first time using high-performance liquid chromatography (HPLC) with immunoaffinity columns(IAC) as the clean-up step. The average recoveries for OTA in grape juice ranged from 54.2 to 86.6% with the coefficient of variation lower than 17.3% in lowest spiked level (0.5 µg/L). The estimated LOD and LOQ of OTA were 0.04 µg/L and 0.125 µg/L, respectively. In our study, 70 samples of grape juice evaluated for OTA content. The results showed that in 39 out of 70 samples (55.7%) OTA levels were above the LOQ with the maximum level of 2.6 µg/L and the mean contamination was 0.5 µg/L. Although the mean contamination of OTA in analyzing samples was lower than the MRL set by EU, the high incidence of contamination in these products is worried. Considering the importance of OTA in public health, control of pre- and post-harvest, storage and grape juice manufacturing process, such as HACCP, GAP, and GMP recommended preventive measures are required. PMID:29755546

Determination of ochratoxin A in tissues of wild boar (Sus scrofa L.) by enzymatic digestion (ED) coupled to high-performance liquid chromatography with a fluorescence detector (HPLC-FLD).

PubMed

Luci, Giacomo; Intorre, Luigi; Ferruzzi, Guido; Mani, Danilo; Giuliotti, Lorella; Pretti, Carlo; Tognetti, Rosalba; Bertini, Simone; Meucci, Valentina

2018-03-01

Ochratoxin A (OTA) is a secondary toxic metabolite synthesized by Aspergillus or Penicillium species, which can contaminate various crops. The International Agency for Research on Cancer (IARC) classified OTA as a group 2B possible human carcinogen. The aim of the present study was to assess OTA concentrations in tissues of wild boar (Sus scrofa L.) from Tuscany (Italy). Over a period of 2 years, samples of muscle, liver, and kidney from 48 wild boars were collected and concentrations of OTA were determined by enzymatic digestion (ED) coupled to high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The highest concentrations of OTA were found in the kidneys of the 48 wild boars analyzed. No difference in concentrations was found based on years of collection and sex while a significantly higher OTA concentration was found in the kidney of the young wild boars with respect to the adult one. Monitoring the quality of meat destined for transformation is a priority in order to decrease the possibility of toxin carry-over to humans. The present study showed that contamination of wild boar meat products by OTA represents a potential emerging source of OTA.

Effect of oxidant stressors and phenolic antioxidants on the ochratoxigenic fungus Aspergillus carbonarius.

PubMed

Crespo-Sempere, Ana; Selma-Lázaro, Cristina; Palumbo, Jeffrey D; González-Candelas, Luis; Martínez-Culebras, Pedro V

2016-01-15

There are few studies dealing with the relationship between oxidative stress and ochratoxin A (OTA) biosynthesis. In this work, we analyzed the effect of the oxidant stressor menadione and the antioxidants 3,5-di-tert-butyl-4-hydroxytoluene (BHT), catechin, resveratrol and a polyphenolic extract on growth, generation of reactive oxygen species (ROS), OTA production and gene expression of antioxidant enzymes of Aspergillus carbonarius. Exposure to menadione concentrations higher than 20 µmol L(-1) led to increases in ROS and OTA levels and a decrease in growth rate. Exposure to 2.5-10 mmol L(-1) BHT also led to higher ROS and OTA levels, although growth rate was only affected above 5 mmol L(-1). Naturally occurring concentrations of catechin, resveratrol and polyphenolic extract barely affected growth rate, but they produced widely different effects on OTA production level depending on the antioxidant concentration used. In general, gene expression of antioxidant enzymes superoxide dismutase (SOD) and peroxiredoxin (PRX) was downregulated after exposure to oxidant and antioxidant concentrations that enhanced OTA production level. Aspergillus carbonarius responds to oxidative stress, increasing OTA production. Nevertheless, the use of naturally occurring concentrations of antioxidant phenolic compounds to reduce oxidative stress is not a valid approach by itself for OTA contamination control in grapes. © 2015 Society of Chemical Industry.

Aspergillus steynii and Aspergillus westerdijkiae as potential risk of OTA contamination in food products in warm climates.

PubMed

Gil-Serna, Jessica; Patiño, Belén; Cortes, Laura; Gonzalez-Jaen, Maria Teresa; Vazquez, Covadonga

2015-04-01

Aspergillus steynii and Aspergillus westerdijkiae are the main ochratoxin A (OTA) producing species of Aspergillus section Circumdati. Due to its recent description, few data are available about the influence of ecophysiological factors on their growth and OTA production profiles. In this work, the effect of temperature (20, 24 and 28 °C) and water activity (aw) (0.928, 0.964 and 0.995) on growth, sporulation and OTA production by these fungi was examined in CYA and media prepared from paprika, green coffee, anise, grapes, maize and barley. Growth was positively affected by the highest temperature and aw values indicating that both species might be expected in warm climates or storage conditions. However, optimal growth conditions showed differences depending on the medium. OTA production was markedly affected by substrate and showed qualitative and quantitative differences. Both species, especially A. steynii, represent a great potential risk of OTA contamination due to their high production in a variety of conditions and substrates, in particular in barley and paprika-based media. Additionally, neither growth nor sporulation did result good indicators of OTA production by A. steynii or A. westerdijkiae; therefore, specific and highly-sensitive detection methods become essential tools for control strategies to reduce OTA risk by these species. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ochratoxin A production by Penicillium thymicola.

PubMed

Nguyen, Hai D T; McMullin, David R; Ponomareva, Ekaterina; Riley, Robert; Pomraning, Kyle R; Baker, Scott E; Seifert, Keith A

2016-08-01

Ochratoxin A (OTA) is a mycotoxin produced by some Aspergillus and Penicillium species that grow on economically important agricultural crops and food products. OTA is classified as Group 2B carcinogen and is potently nephrotoxic, which is the basis for its regulation in some jurisdictions. Using high resolution mass spectroscopy, OTA and ochratoxin B (OTB) were detected in liquid culture extracts of Penicillium thymicola DAOMC 180753 isolated from Canadian cheddar cheese. The genome of this strain was sequenced, assembled and annotated to probe for putative genes involved in OTA biosynthesis. Known OTA biosynthetic genes from Penicillium verrucosum or Penicillium nordicum, two related Penicillium species that produce OTA, were not found in P. thymicola. However, a gene cluster containing a polyketide synthase (PKS) and PKS-nonribosomal peptide synthase (NRPS) hybrid encoding genes were located in the P. thymicola genome that showed a high degree of similarity to OTA biosynthetic enzymes of Aspergillus carbonarius and Aspergillus ochraceus. This is the first report of ochratoxin from P. thymicola and a new record of the species in Canada. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

A Polyketide Synthase Encoded by the Gene An15g07920 Is Involved in the Biosynthesis of Ochratoxin A in Aspergillus niger.

PubMed

Zhang, Jian; Zhu, Liuyang; Chen, Haoyu; Li, Min; Zhu, Xiaojuan; Gao, Qiang; Wang, Depei; Zhang, Ying

2016-12-28

The polyketide synthase gene An15g07920 was known in Aspergillus niger CBS 513.88 as putatively involved in the production of ochratoxin A (OTA). Genome resequencing analysis revealed that the gene An15g07920 is also present in the ochratoxin-producing A. niger strain 1062. Disruption of An15g07920 in A. niger 1062 removed its capacity to biosynthesize ochratoxin β (OTβ), ochratoxin α (OTα), and OTA. These results indicate that the polyketide synthase encoded by An15g07920 is a crucial player in the biosynthesis of OTA, in the pathway prior to the phenylalanine ligation step. The gene An15g07920 reached its maximum transcription level before OTA accumulation reached its highest level, confirming that gene transcription precedes OTA production. These findings will not only help explain the mechanism of OTA production in A. niger but also provide necessary information for the development of effective diagnostic, preventive, and control strategies to reduce the risk of OTA contamination in foods.

Rolling chain amplification based signal-enhanced electrochemical aptasensor for ultrasensitive detection of ochratoxin A.

PubMed

Huang, Lin; Wu, Jingjing; Zheng, Lei; Qian, Haisheng; Xue, Feng; Wu, Yucheng; Pan, Daodong; Adeloju, Samuel B; Chen, Wei

2013-11-19

A novel electrochemical aptasensor is described for rapid and ultrasensitive detection of ochratoxin A (OTA) based on signal enhancement with rolling circle amplification (RCA). The primer for RCA was designed to compose of a two-part sequence, one part of the aptamer sequence directed against OTA while the other part was complementary to the capture probe on the electrode surface. In the presence of target OTA, the primer, originally hybridized with the RCA padlock, is replaced to combine with OTA. This induces the inhibition of RCA and decreases the OTA sensing signal obtained with the electrochemical aptasensor. Under the optimized conditions, ultrasensitive detection of OTA was achieved with a limit of detection (LOD) of 0.065 ppt (pg/mL), which is much lower than previously reported. The electrochemical aptasensor was also successfully applied to the determination of OTA in wine samples. This ultrasensitive electrochemical aptasensor is of great practical importance in food safety and could be widely extended to the detection of other toxins by replacing the sequence of the recognition aptamer.

Recent Advances for the Detection of Ochratoxin A.

PubMed

Ha, Tai Hwan

2015-12-04

Ochratoxin A (OTA) is one of the mycotoxins secreted by Aspersillus and Penicillium that can easily colonize various grains like coffee, peanut, rice, and maize. Since OTA is a chemically stable compound that can endure the physicochemical conditions of modern food processing, additional research efforts have been devoted to develop sensitive and cost-effective surveillance solutions. Although traditional chromatographic and immunoassays appear to be mature enough to attain sensitivity up to the regulation levels, alternative detection schemes are still being enthusiastically pursued in an attempt to meet the requirements of rapid and cost-effective detections. Herein, this review presents recent progresses in OTA detections with minimal instrumental usage, which have been facilitated by the development of OTA aptamers and by the innovations in functional nanomaterials. In addition to the introduction of aptamer-based OTA detection techniques, OTA-specific detection principles are also presented, which exclusively take advantage of the unique chemical structure and related physicochemical characteristics.

Occurrence of ochratoxin A in cocoa products and chocolate.

PubMed

Serra Bonvehí, Josep

2004-10-06

In this work, the occurrence of ochratoxin A (OTA) in 170 samples of cocoa products of different geographical origins was studied. An immunoaffinity column with HPLC separation was developed to quantify low levels of OTA in cocoa bean, cocoa cake, cocoa mass, cocoa nib, cocoa powder, cocoa shell, cocoa butter, chocolate, and chocolate cream with >80% recoveries. The method was validated by performing replicate analyses of uncontaminated cocoa material spiked at three different levels of OTA (1, 2, and 5 microg/kg). The data obtained were related on the acceptable safe daily exposure for OTA. The highest levels of OTA were detected in roasted cocoa shell and cocoa cake (0.1-23.1 microg/kg) and only at minor levels in the other cocoa products. Twenty-six cocoa and chocolate samples were free from detectable OTA (<0.10 microg/kg). In roasted cocoa powder 38.7% of the samples analyzed contained OTA at levels ranging from 0.1 to 2 microg/kg, and 54.8% was contaminated at >2 microg/kg (and 12 samples at >3 microg/kg). Ochratoxin A was detected in cocoa bean at levels from 0.1 to 3.5 microg/kg, the mean concentration being 0.45 microg/kg; only one sample exceeded 2 microg/kg (4.7%). In contrast, 51.2% of cocoa cake samples contained OTA at levels > or =2 microg/kg, among which 16 exceeded 5 microg/kg (range of 5-9 microg/kg). These results indicate that roasted cocoa powder is not a major source of OTA in the diet.

Simply amplified electrochemical aptasensor of ochratoxin A based on exonuclease-catalyzed target recycling.

PubMed

Tong, Ping; Zhang, Lan; Xu, Jing-Juan; Chen, Hong-Yuan

2011-11-15

A new "signal-on" aptasensor for ultrasensitive detection of Ochratoxin A (OTA) in wheat starch was developed based on exonuclease-catalyzed target recycling. To construct the aptasensor, a ferrocene (Fc) labeled probe DNA (S1) was immobilized on a gold electrode (GE) via Au-S bonding for the following hybridization with the complementary OTA aptamer, with the labeled Fc on S1 far from the GE surface. In the presence of analyte OTA, the formation of aptamer-OTA complex would result in not only the dissociation of aptamer from the double-strand DNA but also the transformation of the probe DNA into a hairpin structure. Subsequently, the OTA could be liberated from the aptamer-OTA complex for analyte recycling due to the employment of exonuclease, which is a single-stranded DNA specific exonuclease to selectively digest the appointed DNA (aptamer). Owing to the labeled Fc in close proximity to the electrode surface caused by the formation of the hairpin DNA and to the analyte recycling, differential pulse voltammetry (DPV) signal could be produced with enhanced signal amplification. Based on this strategy, an ultrasensitive aptasensor for the detection of OTA could be exhibited with a wide linear range of 0.005-10.0ngmL(-1) with a low detection limit (LOD) of 1.0pgmL(-1) OTA (at 3σ). The fabricated biosensor was then applied for the measurement of OTA in real wheat starch sample and validated by ELISA method. Copyright © 2011 Elsevier B.V. All rights reserved.

Effects of Ochratoxin A on Livestock Production

PubMed Central

Battacone, Gianni; Nudda, Anna; Pulina, Giuseppe

2010-01-01

Ochratoxin A (OTA) contamination often causes large economic losses on livestock production. The intake of feed contaminated by OTA also represents a potential risk for animal health and a food safety issue due to the transfer of the toxin through the food chain to humans. The aim of this paper is to review the available literature on: (1) the frequency and degree of occurrence of OTA in different feedstuffs; (2) the toxicological effects of OTA intake on the performance of the main livestock (i.e., poultry, swine, cattle, goats and sheep); and (3) the transfer of OTA, or its metabolites, from animal feed into animal products such as milk, meat and eggs. PMID:22069661

Method for analysis dried vine fruits contaminated with ochratoxin A.

PubMed

Galvis-Sánchez, Andrea C; Barros, Antonio S; Delgadillo, Ivonne

2008-06-09

The EU maximum limit of 10 microg kg(-1) of OTA for dried vine fruits has been established since 2002 (European Commission, 2005). The presented work explore the capability of using Fourier infrared spectroscopy attenuated total reflection (FTIR-ATR) for the detection of ochratoxin A (OTA) in dried vine fruits in a range of concentration between 2 and 50 microg kg(-1) OTA. The method developed included a sample pretreatment using a C18 cartridge which was efficient for the isolation of the mycotoxin. The PLS1 analysis of the spectrum of sultanas spiked with different OTA concentrations showed a good correlation between the spectral data and reference concentration for OTA (R(2)=0.85).

Quercetin protects human peripheral blood mononuclear cells from OTA-induced oxidative stress, genotoxicity, and inflammation.

PubMed

Periasamy, Ramyaa; Kalal, Iravathy Goud; Krishnaswamy, Rajashree; Viswanadha, VijayaPadma

2016-07-01

Ochratoxin A (OTA) is one of the most abundant food-contaminating mycotoxins world wide, and is detrimental to human and animal health. This study evaluated the protective effect of quercetin against OTA-induced cytotoxicity, genotoxicity, and inflammatory response in lymphocytes. Cytotoxicity determined by MTT assay revealed IC20 value of OTA to be 20 µM, which was restored to near control values by pretreatment with quercetin. Oxidative stress parameters such as antioxidant enzymes, LPO and PCC levels indicated that quercetin exerted a protective effect on OTA-induced oxidative stress. Quercetin exerted an antigenotoxic effect on OTA-induced genotoxicity, by significantly reducing the number of structural aberrations in chromosomes and comet parameters like, % olive tail moment from 2.76 ± 0.02 to 0.56 ± 0.02 and % tail DNA from 56.23 ± 2.56 to 12.36 ± 0.56 as determined by comet assay. OTA-induced NO, TNF-α, IL-6, and IL-8 were significantly reduced in the quercetin pretreated samples indicating its anti-inflammatory role. Our results demonstrate for the first time that quercetin exerts a cytoprotective effect against OTA-induced oxidative stress, genotoxicity, and inflammation in lymphocytes. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 855-865, 2016. © 2014 Wiley Periodicals, Inc.

Ochratoxin A in grain dust--estimated exposure and relations to agricultural practices in grain production.

PubMed

Halstensen, Anne Straumfors; Nordby, Karl-Christian; Elen, Oleif; Eduard, Wijnand

2004-01-01

Ochratoxin A (OTA) is a nephrotoxin frequently contaminating grains. OTA inhalation during grain handling may therefore represent a health risk to farmers, and was the subject of this study. Airborne and settled grain dust was collected during grain work on 84 Norwegian farms. Climate and agricultural practices on each farm were registered. Penicillium spp., Aspergillus spp. and OTA in settled dust were measured. Settled dust contained median 4 microg OTA/kg dust (range 2-128), correlating with Penicillium spp. (median 40 cfu/mg; range 0-32000, rs =0.33; p < 0.01). Similar levels were found across grain species, districts and agricultural practices. Penicillium levels, but not OTA levels, were higher in storage than in threshing dust (p=0.003), and increased with storage time (rs =0.51, p < 0.001). Farmers were exposed to median 1 mg/m3 (range 0.2-15) dust during threshing and median 7 mg/m3 (range 1-110) dust during storage work, equalling median 3.7 pg/m3 (range 0.6-200) and median 40 pg/m3 (range 2-14000) OTA, respectively (p < 0.001). Agricultural practices could not predict OTA, Penicillium or Aspergillus contamination. Compared to oral intake of OTA, the inhalant exposure during grain work was low, although varying by more than 1,000-fold. However, the farmers may occasionally be highly exposed, particularly during handling of stored grain.

Surface plasmon resonance biosensor for the detection of ochratoxin A in cereals and beverages.

PubMed

Yuan, Jing; Deng, Dawei; Lauren, Denis R; Aguilar, Marie-Isabel; Wu, Yinqiu

2009-12-10

Ochratoxins are a group of mycotoxins produced as secondary metabolites by fungi which contaminate a large variety of food and feed commodities. Due to their teratogenic and carcinogenic properties, ochratoxins present a serious hazard to human and animal health. There is an increasing need to establish a simple sensitive method to detect these toxins. Here we report a rapid and highly sensitive surface plasmon resonance (SPR) assay of ochratoxin A (OTA) using Au nanoparticles for signal enhancement on a mixed self-assembled monolayer (mSAM) surface. A competitive immunoassay format was used for the development of the OTA immunoassay, which is based on the immobilization of target OTA through its ovalbumin (OVA) conjugate with a polyethylene glycol (PEG) linker. The new OTA conjugate (OTA-PEG-OVA) showed remarkably enhanced performance characteristics compared with those based on the immobilization of a commercial bovine serum albumin BSA-OTA conjugate without a PEG linker. Although OTA concentrations as low as 1.5 ng mL(-1) could be directly detected on this surface, the limit of detection (LOD) can be dramatically improved to 0.042 ng mL(-1) for OTA by applying large gold nanoparticles (40 nm) for signal enhancement. Various chemical conditions to minimize the influence of the food matrix on assay performance were also investigated. Grain samples were simply extracted with 50% methanol and liquid samples treated with poly(vinylpyrrolidone) (PVP) (3 or 5%), without any sample clean-up or pre-concentration step prior to analysis. The LODs for OTA in oats and corn were 0.3 and 0.5 ng g(-1), respectively, while in wine and other beverages, LODs ranged from 0.058 to 0.4 ng mL(-1). No cross-reactivity was observed with three other common mycotoxins. In addition, the mSAM/OTA-PEG-OVA surface exhibited high stability with over 600 binding/regeneration cycles. This approach with simple sample preparation provides a powerful tool for the rapid and sensitive quantitative determination of OTA in food matrices.

Luminescence resonance energy transfer (LRET) aptasensor for ochratoxin A detection using upconversion nanoparticles

NASA Astrophysics Data System (ADS)

Jo, Eun-Jung; Byun, Ju-Young; Mun, Hyoyoung; Kim, Min-Gon

2017-07-01

We report an aptasensor for homogeneous ochratoxin A (OTA) detection based on luminescence resonance energy transfer (LRET). This system uses upconversion nanoparticles (UCNPs), such as NaYF4:Yb3+, Er 3+, as the donor. The aptamer includes the optimum-length linker (5-mer-length DNA) and OTA-specific aptamer sequences. Black hole quencher 1 (BHQ1), as the acceptor, was modified at the 3' end of the aptamer sequence. BHQ1 plays as a quencher in LRET aptasensor and shows absorption at 543 nm, which overlaps with well the emission of the UCNPs. When OTA is added, the BHQ1-labeled OTA aptamer was folded due to the formation of the G-quadruplex-OTA complex, which induced the BHQ1 close to the UCNPs. Consequently, resonance energy transfer between UCNPs (donor) and BHQ1 (acceptor) enables quenching of upconversion luminescence signals under laser irradiation of 980 nm. Our results showed that the LRET-based aptasensor allows specific OTA analysis with a limit of detection of 0.03 ng/mL. These results demonstrated that the OTA in diverse foods can be detected specifically and sensitively in a homogeneous manner.

Qualitative and quantitative analysis of ochratoxin A contamination in green coffee beans using Fourier transform near infrared spectroscopy.

PubMed

Taradolsirithitikul, Panchita; Sirisomboon, Panmanas; Dachoupakan Sirisomboon, Cheewanun

2017-03-01

Ochratoxin A (OTA) contamination is highly prevalent in a variety of agricultural products including the commercially important coffee bean. As such, rapid and accurate detection methods are considered necessary for the identification of OTA in green coffee beans. The goal of this research was to apply Fourier transform near infrared spectroscopy to detect and classify OTA contamination in green coffee beans in both a quantitative and qualitative manner. PLSR models were generated using pretreated spectroscopic data to predict the OTA concentration. The best model displayed a correlation coefficient (r) of 0.814, a standard error of prediction (SEP and bias of 1.965 µg kg -1 and 0.358 µg kg -1 , respectively. Additionally, a PLS-DA model was also generated, displaying a classification accuracy of 96.83% for a non-OTA contaminated model and 80.95% for an OTA contaminated model, with an overall classification accuracy of 88.89%. The results demonstrate that the developed model could be used for detecting OTA contamination in green coffee beans in either a quantitative or qualitative manner. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Influence of Fermentation and Drying Materials on the Contamination of Cocoa Beans by Ochratoxin A

PubMed Central

Dano, Sébastien Djédjé; Manda, Pierre; Dembélé, Ardjourma; Abla, Ange Marie-Joseph Kouassi; Bibaud, Joel Henri; Gouet, Julien Zroh; Sika, Charles Bruno Ze Maria

2013-01-01

Ochratoxin A (OTA) is a mycotoxin produced mainly by species of Aspergillus and Penicillium. Contamination of food with OTA is a major consumer health hazard. In Côte d’Ivoire, preventing OTA contamination has been the subject of extensive study. The current study was conducted to evaluate the influence of fermentation and drying materials on the OTA content in cocoa. For each test, 7000 intact cocoa pods were collected, split open to remove the beans, fermented using 1 of 3 different materials, sun-dried on 1 of 3 different platform types and stored for 30 days. A total of 22 samples were collected at each stage of post-harvesting operations. The OTA content in the extracted samples was then quantified by high-performance liquid chromatography. OTA was detected in beans at all stages of post-harvesting operations at varying levels: pod-opening (0.025 ± 0.02 mg/kg), fermentation (0.275 ± 0.2 mg/kg), drying (0.569 ± 0.015 mg/kg), and storage (0.558 ± 0.04 mg/kg). No significant relationships between the detected OTA level and the materials used in the fermentation and drying of cocoa were observed. PMID:24287569

Impedimetric Label-Free Immunosensor on Disposable Modified Screen-Printed Electrodes for Ochratoxin A

PubMed Central

Malvano, Francesca; Albanese, Donatella; Crescitelli, Alessio; Pilloton, Roberto; Esposito, Emanuela

2016-01-01

An impedimetric label-free immunosensor on disposable screen-printed carbon electrodes (SPCE) for quantitative determination of Ochratoxin A (OTA) has been developed. After modification of the SPCE surface with gold nanoparticles (AuNPs), the anti-OTA was immobilized on the working electrode through a cysteamine layer. After each coating step, the modified surfaces were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The capacitance was chosen as the best parameter that describes the reproducible change in electrical properties of the electrode surface at different OTA concentrations and it was used to investigate the analytical parameters of the developed immunosensor. Under optimized conditions, the immunosensor showed a linear relationship between 0.3 and 20 ng/mL with a low detection limit of 0.25 ng/mL, making it suitable to control OTA content in many common food products. Lastly, the immunosensor was used to measure OTA in red wine samples and the results were compared with those registered with a competitive ELISA kit. The immunosensor was sensitive to OTA lower than 2 μg/kg, which represents the lower acceptable limit of OTA established by European legislation for common food products. PMID:27376339

Impedimetric Label-Free Immunosensor on Disposable Modified Screen-Printed Electrodes for Ochratoxin A.

PubMed

Malvano, Francesca; Albanese, Donatella; Crescitelli, Alessio; Pilloton, Roberto; Esposito, Emanuela

2016-06-30

An impedimetric label-free immunosensor on disposable screen-printed carbon electrodes (SPCE) for quantitative determination of Ochratoxin A (OTA) has been developed. After modification of the SPCE surface with gold nanoparticles (AuNPs), the anti-OTA was immobilized on the working electrode through a cysteamine layer. After each coating step, the modified surfaces were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The capacitance was chosen as the best parameter that describes the reproducible change in electrical properties of the electrode surface at different OTA concentrations and it was used to investigate the analytical parameters of the developed immunosensor. Under optimized conditions, the immunosensor showed a linear relationship between 0.3 and 20 ng/mL with a low detection limit of 0.25 ng/mL, making it suitable to control OTA content in many common food products. Lastly, the immunosensor was used to measure OTA in red wine samples and the results were compared with those registered with a competitive ELISA kit. The immunosensor was sensitive to OTA lower than 2 μg/kg, which represents the lower acceptable limit of OTA established by European legislation for common food products.

Effect of rMnSOD on Sodium Reabsorption in Renal Proximal Tubule in Ochratoxin A-Treated Rats.

PubMed

Damiano, Sara; Puzio, Maria V; Squillacioti, Caterina; Mirabella, Nicola; Zona, Enrica; Mancini, Aldo; Borrelli, Antonella; Astarita, Carlo; Boffo, Silvia; Giordano, Antonio; Avallone, Luigi; Florio, Salvatore; Ciarcia, Roberto

2018-01-01

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium that represent toxic real threat for human beings and animal health. In this study we evaluated the effect of a new recombinant mitochondrial manganese containing superoxide dismutase (rMnSOD) on oxidative stress and on the alterations of fluid reabsorption in renal proximal tubule (PT) as possible causes of OTA nephrotoxicity. Finally, we have measured the concentration of O 2 - in the kidney through dihydroethidium assay (DHE) and nitric oxide (NO) concentration through nitrites and nitrates assay. Male Sprague Dawley rats weighing 120-150 g were treated for 14 days by gavage, as follows: Control group, 12 rats received a corresponding amount of saline solution (including 10% DMSO); rMnSOD group, 12 rats treated with rMnSOD (10 µg/kg bw); OTA group, 12 rats treated with OTA (0.5 mg/kg bw) dissolved in 10% DMSO and then scaled to required volume with corn oil; rMnSOD + OTA, 12 rats treated with rMnSOD (10 µg/kg bw) plus OTA (0.5 mg/kg bw). Our results have shown that rMnSOD restores the alteration of reabsorption in PT in rats treated with OTA plus rMnSOD, probably through the response to pressure natriuresis, where nitric oxide plays a key role. Moreover, rMnSOD prevents the nephrotoxicity induced by OTA probably restoring the balance between superoxide and NO that is most probably the cause of hypertension and renal functional alterations through the inhibition of NO synthase. In conclusion these data provide important information for understanding of mechanism of toxic action of OTA. J. Cell. Biochem. 119: 424-430, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Inhibitory Effect of Essential Oils on Aspergillus ochraceus Growth and Ochratoxin A Production

PubMed Central

Selvaraj, Jonathan Nimal; Wang, Yan; Zhao, Yueju; Zhou, Lu; Liu, Xiao; Liu, Yang

2014-01-01

Ochratoxin A (OTA) is a mycotoxin which is a common contaminant in grains during storage. Aspergillus ochraceus is the most common producer of OTA. Essential oils play a crucial role as a biocontrol in the reduction of fungal contamination. Essential oils namely natural cinnamaldehyde, cinnamon oil, synthetic cinnamaldehyde, Litsea citrate oil, citral, eugenol, peppermint, eucalyptus, anise and camphor oils, were tested for their efficacy against A. ochraceus growth and OTA production by fumigation and contact assays. Natural cinnamaldehyde proved to be the most effective against A. ochraceus when compared to other oils. Complete fungal growth inhibition was obtained at 150–250 µL/L with fumigation and 250–500 µL/L with contact assays for cinnamon oil, natural and synthetic cinnamaldehyde, L. citrate oil and citral. Essential oils had an impact on the ergosterol biosynthesis and OTA production. Complete inhibition of ergosterol biosynthesis was observed at ≥100 µg/mL of natural cinnamaldehyde and at 200 µg/mL of citral, but total inhibition was not observed at 200 µg/mL of eugenol. But, citral and eugenol could inhibit the OTA production at ≥75 µg/mL and ≥150 µg/mL respectively, while natural cinnamaldehyde couldn’t fully inhibit OTA production at ≤200 µg/mL. The inhibition of OTA by natural cinnamaldehyde is mainly due to the reduction in fungal biomass. However, citral and eugenol could significant inhibit the OTA biosynthetic pathway. Also, we observed that cinnamaldehyde was converted to cinnamic alcohol by A. ochraceus, suggesting that the antimicrobial activity of cinnamaldehyde was mainly attributed to its carbonyl aldehyde group. The study concludes that natural cinnamaldehyde, citral and eugenol could be potential biocontrol agents against OTA contamination in storage grains. PMID:25255251

Pathology of ochratoxin A-induced nephrotoxicity in Japanese quail and its protection by sea buckthorn (Hippophae rhamnoides L.).

PubMed

Patial, V; Asrani, R K; Patil, R D; Ledoux, D R; Rottinghaus, G E

2013-12-01

The present study was designed to study the protective effect of sea buckthorn (SBT) against renal damage induced by ochratoxin A (OTA) in Japanese quail. Day-old quail chicks were divided into six groups and fed a basal quail chick mash containing 2% SBT leaf powder (group SX), OTA at a dietary level of 3 ppm (group OX), 25 ppm L-beta-phenylalanine (Phe) plus 3 ppm OTA (group OP), 2% dietary level of SBT leaf powder plus 3 ppm OTA (group OS), SBT leaf extract at a level of 10%/L of drinking water plus 3 ppm OTA (group OSS), and a standard toxin-free feed (group CX, control) for 21 days. OTA at 3 ppm level in diet grossly revealed mild to moderate renal swelling in OX birds, and the severity was less in the case of OS, OSS, and OP birds. Microscopically, degenerative, necrotic, and inflammatory changes were observed in OX birds, but the changes were less severe in OS, OSS, and OP birds. Ultrastructural studies revealed remarkable and consistent changes in the proximal convoluted tubules (PCTs), with severe damage of mitochondria and endoplasmic reticulum in OX birds, whereas SBT-treated birds (groups OS, OSS) had mild changes in mitochondria. A moderate to marked increase in number of peroxisomes in the cytoplasm of PCTs was a consistent finding in the Phe- and SBT-treated groups kept on OTA in comparison to the group fed OTA alone. In conclusion, the inclusion of 2% SBT leaf powder in feed and SBT leaf extract in water provided partial protection against OTA-induced nephropathy in Japanese quail.

[Health technology assessment: a multidisciplinary approach for selecting innovations in the health service].

PubMed

Cavallo, Maria Caterina

2013-01-01

Technological evolution and the increasing requests of a more qualified health care have challenged politicians to evaluate the economical sustainability of proposed innovations. The objective of government health policies is to guarantee real advances in the quality of care to all citizens. Since 1965, independent research centers have analyzed this issue for the US Congress. In 1973, Congress endorsed the establishment of an Office of Technology Assessment (OTA) to discover the best strategies for evaluating such advances. OTA have proposed the following criteria to identify possible beneficial innovations to be introduced into routine health care: effectiveness, safeness, worth, costs, cost-effectiveness ratio and cost patient-benefit ratio. This review analyzes in detail the pathway that each medical innovation follows in order to identify which technological evolutions might prove to be truly beneficial and sustainable for the community.

Assessment of soil and water contaminants from selected locations in and near the Idaho Army National Guard Orchard Training Area, Ada County, Idaho, 2001-2003

USGS Publications Warehouse

Parliman, D.J.

2004-01-01

In 2001, the National Guard Bureau and the U.S. Geological Survey began a project to compile hydrogeologic data and determine presence or absence of soil, surface-water, and ground-water contamination at the Idaho Army National Guard Orchard Training Area in southwestern Idaho. Between June 2002 and April 2003, a total of 114 soil, surface-water, ground-water, precipitation, or dust samples were collected from 68 sample sites (65 different locations) in the Orchard Training Area (OTA) or along the vehicle corridor to the OTA. Soil and water samples were analyzed for concentrations of selected total trace metals, major ions, nutrients, explosive compounds, semivolatile organics, and petroleum hydrocarbons. Water samples also were analyzed for concentrations of selected dissolved trace metals and major ions. Distinguishing naturally occurring large concentrations of trace metals, major ions, and nutrients from contamination related to land and water uses at the OTA was difficult. There were no historical analyses for this area to compare with modern data, and although samples were collected from 65 locations in and near the OTA, sampled areas represented only a small part of the complex OTA land-use areas and soil types. For naturally occurring compounds, several assumptions were made?anomalously large concentrations, when tied to known land uses, may indicate presence of contamination; naturally occurring concentrations cannot be separated from contamination concentrations in mid- and lower ranges of data; and smallest concentrations may represent the lowest naturally occurring range of concentrations and (or) the absence of contaminants related to land and water uses. Presence of explosive, semivolatile organic (SVOC), and petroleum hydrocarbon compounds in samples indicates contamination from land and water uses. In areas along the vehicle corridor and major access roads within the OTA, most trace metal, major ion, and nutrient concentrations in soil samples were not in the upper 10th percentile of data, but concentrations of 25 metals, ions, or nutrients were in the upper 10th percentile in a puddle sample near the heavy equipment maneuvering area, MPRC-H. The largest concentrations of tin, ammonia, and nitrite plus nitrate (as nitrogen) in water from the OTA were detected in a sample from this puddle. Petroleum hydrocarbons were the most common contaminant, detected in all soil and surface-water samples. An SVOC, bis (2-ethylhexyl) phthalate, a plasticizer, was detected at a site along the vehicle corridor. In Maneuver Areas within the OTA, many soil samples contained at least one trace metal, major ion, or nutrient in the upper 10th percentile of data, and the largest concentrations of cobalt, iron, mercury, titanium, sodium, ammonia, or total phosphorus were detected in 6 of 13 soil samples outside the Tadpole Lake area. The largest concentrations of aluminum, arsenic, beryllium, nickel, selenium, silver, strontium, thallium, vanadium, chloride, potassium, sulfate, and nitrite plus nitrate were detected in soil samples from the Tadpole Lake area. Water from Tadpole Lake contained the largest total concentrations of 19 trace metals, 4 major ions, and 1 nutrient. Petroleum hydrocarbons were detected in 5 soil samples and water from Tadpole Lake. SVOCs related to combustion of fuel or plasticizers were detected in 1 soil sample. Explosive compounds were detected in 1 precipitation sample.In the Impact Area within the OTA, most soil samples contained at least one trace metal, major ion, or nutrient in the upper 10th percentile of data, and the largest concentrations of barium, chromium, copper, manganese, lead, or orthophosphate were detected in 6 of the 18 soil samples. Petroleum hydrocarbons were detected in 4 soil samples, SVOCs in 6 samples, and explosive compounds in 4 samples. In the mobilization and training equipment site (MATES) compound adjacent to the OTA, all soil and water samples contained at lea

FTIR-ATR infrared spectroscopy for the detection of ochratoxin A in dried vine fruit.

PubMed

Galvis-Sánchez, Andrea C; Barros, Antonio; Delgadillo, Ivonne

2007-11-01

A method of screening sultanas for ochratoxin A (OTA) contamination, using mid-infrared spectroscopy/Golden Gate single-reflection ATR (attenuated total reflection), is described. The main spectral characteristics of sultanas from different sources were identified in a preliminary acquisition and spectral analysis study. Principal component analysis (PCA) showed that samples of various origins had different spectral characteristics, especially in water content and the fingerprint region. A lack of reproducibility was observed in the spectra acquired on different days. However, spectral repeatability was greatly improved when water activity of the sample was set at 0.62. A calibration curve of OTA was constructed in the range 10-40 microg OTA kg(-1). Samples with OTA levels higher than 20 microg kg(-1) were separated from samples contaminated with a lower concentration (10 microg OTA kg(-1)) and from uncontaminated samples. The reported methodology is a reliable and simple technique for screening dried vine fruit for OTA.

Ochratoxin A in Moroccan foods: occurrence and legislation.

PubMed

Zinedine, Abdellah

2010-05-01

Ochratoxin A (OTA) is secondary metabolite naturally produced in food and feed by toxigenic fungi, especially some Aspergillus species and Penicillium verucosum. OTA is one of the most studied mycotoxins and is of great interest due to its toxic effects on human and animals. OTA is produced in different food and feed matrices and contaminates a large range of base foods including cereals and derivatives, spices, dried fruits, wine and coffee, etc. Morocco, a North African country, has a climate characterized by high humidity and temperature, which probably favors the growth of molds. This contribution gives an overview of principal investigations about the presence of OTA in foods available in Morocco. Due to its toxicity, OTA presence is increasingly regulated worldwide, especially in countries of the European Union. However, up until now, no regulation limits were in force in Morocco, probably due to the ignorance of the health and economic problems resulting from OTA contamination. Finally, recommendations and future research directions are given required to assess the situation completely.

Ochratoxin A in Moroccan Foods: Occurrence and Legislation

PubMed Central

Zinedine, Abdellah

2010-01-01

Ochratoxin A (OTA) is secondary metabolite naturally produced in food and feed by toxigenic fungi, especially some Aspergillus species and Penicillium verucosum. OTA is one of the most studied mycotoxins and is of great interest due to its toxic effects on human and animals. OTA is produced in different food and feed matrices and contaminates a large range of base foods including cereals and derivatives, spices, dried fruits, wine and coffee, etc. Morocco, a North African country, has a climate characterized by high humidity and temperature, which probably favors the growth of molds. This contribution gives an overview of principal investigations about the presence of OTA in foods available in Morocco. Due to its toxicity, OTA presence is increasingly regulated worldwide, especially in countries of the European Union. However, up until now, no regulation limits were in force in Morocco, probably due to the ignorance of the health and economic problems resulting from OTA contamination. Finally, recommendations and future research directions are given required to assess the situation completely. PMID:22069630

Polyvinylpolypyrrolidone reduces cross-reactions between antibodies and phenolic compounds in an enzyme-linked immunosorbent assay for the detection of ochratoxin A.

PubMed

Robinson, Andrew L; Lee, Hyun Jung; Ryu, Dojin

2017-01-01

Ochratoxin A (OTA) is a fungal metabolite and putative carcinogen which can contaminate a variety of foods such as cereals, wine, and nuts. Commercial ELISA kits are known to give false-positive results for OTA concentrations when phenolic compounds are present. Pistachios represent a food matrix rich in phenolic compounds potentially contaminated with OTA, and were used to model OTA cross-reactivity. Polyvinylpolypyrrolidone (PVPP) was incorporated during extraction of OTA using a commercial ELISA protocol. HPLC methods were used to confirm that PVPP does not interact with OTA and levels of gallic acid and catechin remaining in pistachio extracts decreased with increasing PVPP application. Cross-reactivity of extracts also decreased with increasing PVPP application, and color loss was used as an indicator of anthocyanin removal. Incorporating PVPP into ELISA protocols allows for the continued use of rapid immunological methods in food matrices containing phenolic compounds. Copyright © 2016 Elsevier Ltd. All rights reserved.

Amplified impedimetric immunosensor based on instant catalyst for sensitive determination of ochratoxin A.

PubMed

Tang, Juan; Huang, Yapei; Zhang, Cengceng; Liu, Huiqiong; Tang, Dianping

2016-12-15

A new impedimetric immunosensor for the fast determination of ochratoxin A (OTA) in food samples was developed based on the instant catalyst as enhancer. Initially, the signal tags were prepared via co-immobilization of anti-OTA antibody and amine-terminated dendrimer (PAMAM) on the graphene oxide nanosheets through the covalent interaction, which were utilized as a good platform for combining manganese ion (anti-OTA-GO-PAMAM-Mn(2+)). Upon target OTA introduction, a competitive-type immunoreaction was implemented between the analyte and the immobilized OTA-BSA on the electrode for the anti-OTA antibody on the graphene oxide nanosheets labels. After a competitive immunoassay format, the anti-OTA-GO-PAMAM-Mn(2+) were captured onto the electrode surface, which could induce the in situ formation of MnO2via classical redox reaction between Mn(2+) and KMnO4 on the immunesensing platform. Moreover, the generated MnO2 nanoparticles act as efficient catalyst could catalyze the 4-chloro-1-naphthol (4-CN) oxidation without H2O2 to generate an insoluble precipitation on the platform. Under the optimal conditions, the instant catalyst based impedimetric immunosensor displayed a wide dynamic working range between 0.1pgmL(-1) and 30ngmL(-1). The detection limit (LOD) of the assay was 0.055pgmL(-1). The developed method exhibited high selectivity and can be used for the determination of OTA in real red wine samples. Copyright © 2016 Elsevier B.V. All rights reserved.

PCV2 infection aggravates ochratoxin A-induced nephrotoxicity via autophagy involving p38 signaling pathway in vivo and in vitro.

PubMed

Gan, Fang; Zhou, Yajiao; Qian, Gang; Huang, Da; Hou, Lili; Liu, Dandan; Chen, Xingxiang; Wang, Tian; Jiang, Ping; Lei, Xingen; Huang, Kehe

2018-07-01

Ochratoxin A (OTA) is reported to induce nephrotoxicity in animals and humans. Porcine circovirus type 2 (PCV2) could induce porcine dermatitis and nephropathy syndrome. To date, little is known whether virus infection aggravates mycotoxin-induced toxicity. This work aimed to study the effects of PCV2 infection on OTA-induced nephrotoxicity and its mechanism in vivo and vitro. The results in vivo showed that PCV2 infection aggravated OTA-induced poor growth performance, nephrotoxicity, p38 phosphorylation and autophagy as demonstrated by Atg5, LC3 II and p62 protein expressions in kidney of pigs. The results in vitro indicated that PCV2 infection significantly aggravated OTA-induced nephrotoxicity as demonstrated by cell viabilities, annexin V/PI binding and caspase 3 activities, and induced p38 phosphorylation and autophagy in PK15 cells. p38 inhibitor decreased Atg5 and LC3 protein expression induced by PCV2 infection and OTA combined treatment. Adding autophagy inhibitor 3-MA or CQ alleviated the aggravating effects of PCV2 infection on OTA-induced nephrotoxicity. Atg5-specific siRNA eliminated the aggravating effects of PCV2 infection on OTA-induced nephrotoxicity. Taken together, these data indicate that in vivo and in vitro PCV2 infection aggravated OTA-induced nephrotoxicity via p38-mediated autophagy. Copyright © 2018 Elsevier Ltd. All rights reserved.

A risk assessment of dietary ochratoxin A in the United States

USDA-ARS?s Scientific Manuscript database

Background: Ochratoxin A (OTA) is a mycotoxin (fungal toxin) found in multiple foodstuffs. Because OTA has been shown to cause kidney disease in multiple species, several governmental bodies around the world have set maximum allowable levels of OTA in different foods and beverages. Objectives: In ...

Rapid high-throughput analysis of ochratoxin A by the self-assembly of DNAzyme-aptamer conjugates in wine.

PubMed

Yang, Cheng; Lates, Vasilica; Prieto-Simón, Beatriz; Marty, Jean-Louis; Yang, Xiurong

2013-11-15

We report a new label-free colorimetric aptasensor based on DNAzyme-aptamer conjugate for rapid and high-throughput detection of Ochratoxin A (OTA, a possible human carcinogen, group 2B) in wine. Two oligonucleotides were designed for this detection. One is N1 for biorecognition, which includes two adjacent sequences: the OTA-specific aptamer sequence and the horseradish peroxidase (HRP)-mimicking DNAzyme sequence. The other is a blocking DNA (B2), which is partially complementary to a part of the OTA aptamer and partially complementary to a part of the DNAzyme. The existence of OTA reduces the hybridization between N1 and B2. Thus, the activity of the non-hybridized DNAzyme is linearly correlated with the concentration of OTA up to 30 nM with a limit of detection of 4 nM (3σ). Meanwhile, a double liquid-liquid extraction (LLE) method is accordingly developed to purify OTA from wine. Compared with the existing HPLC-FD or immunoassay methods, the proposed strategy presents the most appropriate balance between accuracy and facility, resulting in a considerable improvement of real-time quality control, and thereby, preventing chronic poisoning caused by OTA contained red wine. Copyright © 2013 Elsevier B.V. All rights reserved.

Teratogenicity of Ochratoxin A and the Degradation Product, Ochratoxin α, in the Zebrafish (Danio rerio) Embryo Model of Vertebrate Development

PubMed Central

Haq, Mehreen; Gonzalez, Nelson; Mintz, Keenan; Jaja-Chimedza, Asha; De Jesus, Christopher Lawrence; Lydon, Christina; Welch, Aaron Z.; Berry, John P.

2016-01-01

Ochratoxins, and particularly ochratoxin A (OTA), are toxic fungal-derived contaminants of food and other agricultural products. Growing evidence supports the degradation of OTA by chemical, enzymatic and/or microbial means as a potential approach to remove this mycotoxin from food products. In particular, hydrolysis of OTA to ochratoxin α (OTα) and phenylalanine is the presumptive product of degradation in most cases. In the current study, we employed the zebrafish (Danio rerio) embryo, as a model of vertebrate development to evaluate, the teratogenicity of OTA and OTα. These studies show that OTA is potently active in the zebrafish embryo toxicity assay (ZETA), and that toxicity is both concentration- and time-dependent with discernible and quantifiable developmental toxicity observed at nanomolar concentrations. On the other hand, OTα had no significant effect on embryo development at all concentrations tested supporting a decreased toxicity of this degradation product. Taken together, these results suggest that ZETA is a useful, and highly sensitive, tool for evaluating OTA toxicity, as well as its degradation products, toward development of effective detoxification strategies. Specifically, the results obtained with ZETA, in the present study, further demonstrate the toxicity of OTA, and support its degradation via hydrolysis to OTα as an effective means of detoxification. PMID:26861395

Ochratoxin A determination in swine muscle and liver from French conventional or organic farming production systems.

PubMed

Hort, Vincent; Nicolas, Marina; Minvielle, Brice; Maleix, Corentin; Desbourdes, Caroline; Hommet, Frédéric; Dragacci, Sylviane; Dervilly-Pinel, Gaud; Engel, Erwan; Guérin, Thierry

2018-05-28

Consumers generally considered organic products to be healthier and safer but data regarding the contamination of organic products are scarce. This study evaluated the impact of the farming system on the levels of ochratoxin A (OTA) in the tissues of French pigs (muscle and liver) reared following three different types of production (organic, Label Rouge and conventional). Because OTA is present at trace levels in animal products, a sensitive ultra-high performance liquid chromatography-tandem mass spectrometry method using stable isotope dilution assay was developed and validated. OTA was detected or quantified (LOQ of 0.10 μg kg -1 ) in 67% (n = 47) of the 70 pig liver samples analysed, with concentrations ranging from <0.10 to 3.65 μg kg -1 . The maximum concentration was found in a sample from organic production but there were no significant differences in the content of OTA between farming systems. OTA was above the LOQ in four out of 25 samples of the pork muscles. A good agreement was found between OTA levels in muscle and liver (liver concentration = 2.9 × OTA muscle concentration, r = 0.981). Copyright © 2018 Elsevier B.V. All rights reserved.

Teratogenicity of Ochratoxin A and the Degradation Product, Ochratoxin α, in the Zebrafish (Danio rerio) Embryo Model of Vertebrate Development.

PubMed

Haq, Mehreen; Gonzalez, Nelson; Mintz, Keenan; Jaja-Chimedza, Asha; De Jesus, Christopher Lawrence; Lydon, Christina; Welch, Aaron; Berry, John P

2016-02-05

Ochratoxins, and particularly ochratoxin A (OTA), are toxic fungal-derived contaminants of food and other agricultural products. Growing evidence supports the degradation of OTA by chemical, enzymatic and/or microbial means as a potential approach to remove this mycotoxin from food products. In particular, hydrolysis of OTA to ochratoxin α (OTα) and phenylalanine is the presumptive product of degradation in most cases. In the current study, we employed the zebrafish (Danio rerio) embryo, as a model of vertebrate development to evaluate, the teratogenicity of OTA and OTα. These studies show that OTA is potently active in the zebrafish embryo toxicity assay (ZETA), and that toxicity is both concentration- and time-dependent with discernible and quantifiable developmental toxicity observed at nanomolar concentrations. On the other hand, OTα had no significant effect on embryo development at all concentrations tested supporting a decreased toxicity of this degradation product. Taken together, these results suggest that ZETA is a useful, and highly sensitive, tool for evaluating OTA toxicity, as well as its degradation products, toward development of effective detoxification strategies. Specifically, the results obtained with ZETA, in the present study, further demonstrate the toxicity of OTA, and support its degradation via hydrolysis to OTα as an effective means of detoxification.

Adsorption of ochratoxin A from grape juice by yeast cells immobilised in calcium alginate beads.

PubMed

Farbo, Maria Grazia; Urgeghe, Pietro Paolo; Fiori, Stefano; Marceddu, Salvatore; Jaoua, Samir; Migheli, Quirico

2016-01-18

Grape juice can be easily contaminated with ochratoxin A (OTA), one of the known mycotoxins with the greatest public health significance. Among the different approaches to decontaminate juice from this mycotoxin, microbiological methods proved efficient, inexpensive and safe, particularly the use of yeast or yeast products. To ascertain whether immobilisation of the yeast biomass would lead to successful decontamination, alginate beads encapsulating Candida intermedia yeast cells were used in our experiments to evaluate their OTA-biosorption efficacy. Magnetic calcium alginate beads were also prepared by adding magnetite in the formulation to allow fast removal from the aqueous solution with a magnet. Calcium alginate beads were added to commercial grape juice spiked with 20 μg/kg OTA and after 48 h of incubation a significant reduction (>80%), of the total OTA content was achieved, while in the subsequent phases (72-120 h) OTA was slowly released into the grape juice by alginate beads. Biosorption properties of alginate-yeast beads were tested in a prototype bioreactor consisting in a glass chromatography column packed with beads, where juice amended with OTA was slowly flowed downstream. The adoption of an interconnected scaled-up bioreactor as an efficient and safe tool to remove traces of OTA from liquid matrices is discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

Double-probe signal enhancing strategy for toxin aptasensing based on rolling circle amplification.

PubMed

Tong, Ping; Zhao, Wei-Wei; Zhang, Lan; Xu, Jing-Juan; Chen, Hong-Yuan

2012-03-15

On the basis of aptamer-based rolling circle amplification (RCA) and magnetic beads (MBs), a highly sensitive electrochemical method was developed for the determination of Ochratoxin A (OTA). Initially, an amino-modified capture DNA was immobilized onto MBs for the following hybridization with an OTA aptamer and a phosphate labeled padlock DNA. In the presence of OTA, the aptamer would dissociate from the bioconjugate, and the padlock DNA would subsequently hybridize with the capture DNA to form a circular template with the aid of the T4 ligase. Next, capture DNA would act as primer to initiate a linear RCA reaction and hence generate a long tandem repeated sequences by phi29 DNA polymerase and dNTPs. Then, two quantum dots (QDs) labeled DNA probes were tagged on the resulted RCA product to indicate the OTA recognition event by electrochemical readout. This strategy, based on the novel design of OTA-mediated DNA circularization, the combination of RCA and double signal probes introduction, could detect OTA down to the level of 0.2 pg mL(-1) with a dynamic range spanning more than 4 orders of magnitude. The proposed approach is tested to determine OTA in red wines and shows good application potential in real samples. Copyright © 2011 Elsevier B.V. All rights reserved.

Inhibition of A. carbonarius growth and reduction of ochratoxin A by bacteria and yeast composites of technological importance in culture media and beverages.

PubMed

Kapetanakou, A E; Kollias, J N; Drosinos, E H; Skandamis, P N

2012-01-16

Five composites of yeast and six of bacterial isolates from fermented products were studied, in order to assess their ability to inhibit Aspergillus carbonarius growth and reduce OTA concentration in culture media and beverages. The antagonistic effect of the above composites against A. carbonarius growth was studied in synthetic grape medium of pH 3.5 and a(w) 0.98, 0.95, 0.92 after incubation at 25°C. Different combinations of initial inocula of bacteria or yeast composites and fungi were used (10(2)cfu/mL vs 10(5)spores/mL; 10(5)cfu/mL vs 10(2)spores/mL; and 10(5)cfu/mL vs 10(5)spores/mL). Regarding the OTA reduction experiment, 10(3) and 10(7)cfu/mL of the bacteria and yeast composites were inoculated in liquid media of different pH (3.0, 4.0, 5.0, and 6.1 or 6.5) and initial OTA concentration (50 and 100μg/L) and incubated at 30°C. Moreover, grape juice, red wine, and beer were supplemented with 100μg/L of OTA and inoculated with composites of 16 yeasts (16YM) and 29 bacterial (29BM) strains (10(7)cfu/mL) to estimate the kinetics of OTA reduction at 25°C for 5days. Fungal inhibition and OTA reduction were calculated in comparison to control samples. None of the bacterial composites inhibited A. carbonarius growth. The high inoculum of yeast composites (10(5) cfu/mL) showed more efficient fungal inhibition compared to cell density of 10(2) cfu/mL. All yeast composites showed higher OTA reduction (up to 65%) compared to bacteria (2-25%), at all studied assays. The maximum OTA reduction was obtained at pH 3.0 by almost all yeast composites. For all studied beverages the decrease in OTA concentration was higher by yeasts (16YM) compared to bacteria (29BM). The highest OTA reduction was observed in grape juice (ca 32%) followed by wine (ca 22%), and beer (ca 12%). The present findings may assist in the control of A. carbonarius growth and OTA production in fermented foodstuffs by the use of proper strains of technological importance. Copyright © 2011 Elsevier B.V. All rights reserved.

Design and synthesis of target-responsive aptamer-cross-linked hydrogel for visual quantitative detection of ochratoxin A.

PubMed

Liu, Rudi; Huang, Yishun; Ma, Yanli; Jia, Shasha; Gao, Mingxuan; Li, Jiuxing; Zhang, Huimin; Xu, Dunming; Wu, Min; Chen, Yan; Zhu, Zhi; Yang, Chaoyong

2015-04-01

A target-responsive aptamer-cross-linked hydrogel was designed and synthesized for portable and visual quantitative detection of the toxin Ochratoxin A (OTA), which occurs in food and beverages. The hydrogel network forms by hybridization between one designed DNA strand containing the OTA aptamer and two complementary DNA strands grafting on linear polyacrylamide chains. Upon the introduction of OTA, the aptamer binds with OTA, leading to the dissociation of the hydrogel, followed by release of the preloaded gold nanoparticles (AuNPs), which can be observed by the naked eye. To enable sensitive visual and quantitative detection, we encapsulated Au@Pt core-shell nanoparticles (Au@PtNPs) in the hydrogel to generate quantitative readout in a volumetric bar-chart chip (V-Chip). In the V-Chip, Au@PtNPs catalyzes the oxidation of H2O2 to generate O2, which induces movement of an ink bar to a concentration-dependent distance for visual quantitative readout. Furthermore, to improve the detection limit in complex real samples, we introduced an immunoaffinity column (IAC) of OTA to enrich OTA from beer. After the enrichment, as low as 1.27 nM (0.51 ppb) OTA can be detected by the V-Chip, which satisfies the test requirement (2.0 ppb) by the European Commission. The integration of a target-responsive hydrogel with portable enrichment by IAC, as well as signal amplification and quantitative readout by a simple microfluidic device, offers a new method for portable detection of food safety hazard toxin OTA.

T Cell Activation in South African HIV-Exposed Infants Correlates with Ochratoxin A Exposure

PubMed Central

Wood, Lianna Frances; Wood, Matthew P.; Fisher, Bridget S.; Jaspan, Heather B.; Sodora, Donald L.

2017-01-01

The introduction of non-breastmilk foods to HIV-infected infants is associated with increased levels of immune activation, which can impact the rate of HIV disease progression. This is particularly relevant in countries where mother-to-child transmission of HIV still occurs at unacceptable levels. The goal of this study was to evaluate the levels of the toxic food contaminant ochratoxin A (OTA) in HIV-exposed South African infants that are either breastfed or consuming non-breast milk foods. OTA is a common mycotoxin, found in grains and soil, which is toxic at high doses but has immunomodulatory properties at lower doses. Samples from HIV-exposed and HIV-unexposed infants enrolled in prospective observational cohort studies were collected and analyzed at birth through 14 weeks of age. We observed that infants consuming non-breast milk foods had significantly higher plasma levels of OTA at 6 weeks of age compared to breastfed infants, increasing until 8 weeks of age. The blood levels of OTA detected were comparable to levels observed in OTA-endemic communities. OTA plasma levels correlated with HIV target cell activation (CCR5 and HLADR expression on CD4+ T cells) and plasma levels of the inflammatory cytokine CXCL10. These findings provide evidence that elevated OTA levels in South African infants are associated with the consumption of non-breastmilk foods and activation of the immune system. Reducing infant OTA exposure has the potential to reduce immune activation and provide health benefits, particularly in those infants who are HIV-exposed or HIV-infected. PMID:29312338

Four-year surveillance for ochratoxin a and fumonisins in retail foods in Japan.

PubMed

Aoyama, Koji; Nakajima, Masahiro; Tabata, Setsuko; Ishikuro, Eiichi; Tanaka, Toshitsugu; Norizuki, Hiroko; Itoh, Yoshinori; Fujita, Kazuhiro; Kai, Shigemi; Tsutsumi, Toru; Takahashi, Masanori; Tanaka, Hiroki; Iizuka, Seiichiro; Ogiso, Motoki; Maeda, Mamoru; Yamaguchi, Shigeaki; Sugiyama, Kei-Ichi; Sugita-Konishi, Yoshiko; Kumagai, Susumu

2010-02-01

Between 2004 and 2007 we examined foods from Japanese retail shops for contamination with ochratoxin A (OTA) and fumonisins B(1), B(2), and B(3). A total of 1,358 samples of 27 different products were examined for OTA, and 831 samples of 16 different products were examined for fumonisins. The limits of quantification ranged from 0.01 to 0.5 microg/kg for OTA and 2 to 10 microg/kg for the fumonisins. OTA was detected in amounts higher than limits of quantification in wheat flour, pasta, oatmeal, rye, buckwheat flour and dried buckwheat noodles, raisins, wine, beer, coffee beans and coffee products, chocolate, cocoa, and coriander. OTA was found in more than 90% of the samples of instant coffee and cocoa, and the highest concentration of OTA, 12.5 microg/kg, was detected in raisins. The concentration of OTA in oatmeal, rye, raisins, wine, and roasted coffee beans varied remarkably from year to year. Fumonisins were detected in frozen and canned corn, popcorn grain, corn grits, cornflakes, corn soups, corn snacks, beer, soybeans, millet, and asparagus. The highest concentrations of fumonisins B(1), B(2), and B(3) were detected in corn grits (1,670, 597, and 281 microg/kg, respectively). All of the samples of corn grits were contaminated with fumonisins, and more than 80% of the samples of popcorn grain and corn snacks contained fumonisins. OTA and fumonisins were detected in several food products in Japan; however, although Japan has not set regulatory levels for these mycotoxins, their concentrations were relatively low.

Aminobacterium thunnarium sp. nov., a mesophilic, amino acid-degrading bacterium isolated from an anaerobic sludge digester, pertaining to the phylum Synergistetes.

PubMed

Hamdi, Olfa; Ben Hania, Wajdi; Postec, Anne; Bouallagui, Hassib; Hamdi, Moktar; Bonin, Patricia; Ollivier, Bernard; Fardeau, Marie-Laure

2015-02-01

A new Gram-staining-positive, non-sporulating, mesophilic, amino acid-degrading anaerobic bacterium, designated strain OTA 102(T), was isolated from an anaerobic sequencing batch reactor treating wastewater from cooking tuna. The cells were curved rods (0.6-2.5×0.5 µm) and occurred singly or in pairs. The strain was motile by means of one lateral flagellum. Strain OTA 102(T) grew at temperatures between 30 and 45 °C (optimum 40 °C), between pH 6.0 and 8.4 (optimum pH 7.2) and NaCl concentrations between 1 and 5 % (optimum 2 %, w/v). Strain OTA 102(T) required yeast extract for growth. Serine, threonine, glycine, cysteine, citrate, fumarate, α-ketoglutarate and pyruvate were fermented. When co-cultured with Methanobacterium formicicum as the hydrogen scavenger, strain OTA 102(T) oxidized alanine, valine, leucine, isoleucine, aspartate, tyrosine, methionine, histidine and asparagine. The genomic DNA G+C content of strain OTA 102(T) was 41.7 mol%. The main fatty acid was iso-C15 : 0. Phylogenetic analysis of the 16S rRNA gene sequence indicated that strain OTA 102(T) was related to Aminobacterium colombiense and Aminobacterium mobile (95.5 and 95.2 % similarity, respectively), of the phylum Synergistetes. On the basis of phylogenetic, genetic and physiological characteristics, strain OTA 102(T) is proposed to represent a novel species of the genus Aminobacterium, Aminobacterium thunnarium sp. nov. The type strain is OTA 102(T) ( = DSM 27500(T) = JCM 19320(T)). © 2015 IUMS.

Amplified fluorescent aptasensor through catalytic recycling for highly sensitive detection of ochratoxin A.

PubMed

Wei, Yin; Zhang, Ji; Wang, Xu; Duan, Yixiang

2015-03-15

This paper describes a novel approach utilizing nano-graphite-aptamer hybrid and DNase I for the amplified detection of ochratoxin A (OTA) for the first time. Nano-graphite can effectively quench the fluorescence of carboxyfluorescein (FAM) labeled OTA specific aptamer due to their strong π-π; stacking interactions; while upon OTA addition, it will bind with aptamer to fold into an OTA-aptamerG-quadruplex structure, which does not adsorb on the surface of nano-graphite and thus retains the dye fluorescence. Meanwhile, the G-quadruplex structure can be cleaved by DNase I, and in such case OTA is delivered from the complex. The released OTA then binds other FAM-labeled aptamers on the nano-graphite surface, and touches off another target recycling, resulting in the successive release of dye-labeled aptamers from the nano-graphite, which leads to significant amplification of the signal. Under the optimized conditions, the present amplified sensing system exhibits high sensitivity toward OTA with a limit of detection of 20nM (practical measurement), which is about 100-fold higher than that of traditional unamplified homogeneous assay. Our developed method also showed high selectivity against other interference molecules and can be applied for the detection of OTA in real red wine samples. The proposed assay is simple, cost-effective, and might open a door for the development of new assays for other biomolecules. This aptasensor is of great practical importance in food safety and could be widely extended to the detection of other toxins by replacing the sequence of the recognition aptamer. Copyright © 2014 Elsevier B.V. All rights reserved.

A survey of spontaneous occurrence of ochratoxin A residues in chicken tissues and concurrence with histopathological changes in liver and kidneys

USGS Publications Warehouse

Milicevic, Dragan; Jovanovic, Milijan; Matekalosverak, Vesna; Radicevic, Tatjana; Petrovic, Milan M.; Lilic, Slobodan

2011-01-01

Toxicological and histopathological investigations of tissues of commercially slaughtered chickens were carried out to provide a preliminary evaluation of the incidence of occurrence of ochratoxin A (OTA) in chicken sold in Serbian retail market. In addition, the etiology of nephropathies of these chickens was elucidated. The majority of these tissue samples were not found to contain measurable amounts of OTA. Moreover, the OTA levels found in analyzed tissues were generally low and there was no positive correlation between the presence of OTA and the frequency of histopathological changes. Histopathological changes such as degenerative changes in the kidneys and liver differed from the classical description of the mycotoxic nephropathy, indicating that the chicken nephropathy observed in Serbia may have a multitoxic etiology with possible synergistic effect between microorganisms and natural toxins, usually present in low concentrations. The low OTA results also suggested that chicken meat available in the retail market in Serbia are unlikely to pose any significant adverse health risk to the consumers with respect to OTA toxicity.

A competitive aptamer chemiluminescence assay for ochratoxin A using a single silica photonic crystal microsphere.

PubMed

Shen, Peng; Li, Wei; Ding, Zhi; Deng, Yang; Liu, Yan; Zhu, Xuerui; Cai, Tingting; Li, Jianlin; Zheng, Tiesong

2018-08-01

We designed a competitive aptamer chemiluminescence assay for ochratoxin A (OTA) on the surface of a single silica photonic crystal microsphere (SPCM) in cereal samples. The structural color of SPCMs is used to recognize and trace the microspheres during process of detection. Anti-aptamer was immobilized on the surface of SPCM. OTA and anti-aptamer competed to bind to aptamer when OTA and its aptamer (labeled by biotin at 5'end) were added in the system. The chemiluminescence signal was developed by the horseradish peroxidase (HRP), luminol and H 2 O 2 . The molecules on the single SPCM can produce enough chemiluminescence signal intensity for quantitative detection for OTA. The linear detection range for OTA was from 1 pg/mL to 1 ng/mL and recovery rates were 89%-95%, 81%-92% and 94%-105% in rice, wheat and corn, respectively. The results showed that the developed method for OTA using a single SPCM has a great application potential in cereal samples. Copyright © 2018 Elsevier Inc. All rights reserved.

Food coloring agents and plant food supplements derived from Vitis vinifera: a new source of human exposure to ochratoxin A.

PubMed

Solfrizzo, Michele; Piemontese, Luca; Gambacorta, Lucia; Zivoli, Rosanna; Longobardi, Francesco

2015-04-08

Grape pomaces are increasingly being used as starting material in the industrial production of plant food supplements (PFS), food coloring, and tartrates, but they are at risk of ochratoxin A (OTA) contamination, a mycotoxin with nephrotoxic and carcinogenic effects. We analyzed 24 commercial PFS and 13 food coloring samples derived from Vitis vinifera, mainly pomaces, using a HPLC-FLD method for OTA determination. OTA was found in 75% of PFS samples and 69% of food coloring samples at levels of <1.16-20.23 μg/kg and <1.16-32.00 μg/kg, respectively. The four commercial leavening agents containing tartrates were found to be negative for OTA. All eight samples collected in two distilleries that use grape pomaces and wine lees to produce tartrates and other byproducts contained OTA at levels of <1.16-240.93 μg/kg. The high incidence of OTA contamination in PFS and food coloring agents derived from V. vinifera suggests that maximum permitted level(s) should be established for this mycotoxin in these products.

Ochratoxin degradation and adsorption caused by astaxanthin-producing yeasts.

PubMed

Péteri, Z; Téren, J; Vágvölgyi, C; Varga, J

2007-05-01

Ochratoxin degrading and adsorbing activities of Phaffia rhodozyma and Xanthophyllomyces dendrorhous isolates were tested. P. rhodozyma CBS 5905 degraded more than 90% of ochratoxin A (OTA) in 15 days at 20 degrees C. The data presented indicate that P. rhodozyma is able to convert OTA to ochratoxin alpha, and this conversion is possibly mediated by an enzyme related to carboxypeptidases. Chelating agents like EDTA and 1,10-phenanthroline inhibited OTA degradation caused by P. rhodozyma indicating that the carboxypeptidase is a metalloprotease, similarly to carboxypeptidase A. The temperature optimum of this enzyme was found to be above 30 degrees C, which is much higher than the temperature optimum for growth of P. rhodozyma cells, which is around 20 degrees C. The enzyme responsible for ochratoxin degradation was found to be cell-bound. Besides, both viable and heat-treated (dead) P. rhodozyma cells were also able to adsorb significant amounts (up to 250 ng ml(-1)) of OTA. Heat treatment enhanced OTA adsorbing activities of the cells. Further studies are in progress to identify the enzyme responsible for OTA degradation in P. rhodozyma.

Ochratoxin A removal by Saccharomyces cerevisiae strains: effect of wine-related physicochemical factors.

PubMed

Petruzzi, Leonardo; Sinigaglia, Milena; Corbo, Maria Rosaria; Beneduce, Luciano; Bevilacqua, Antonio

2013-07-01

This study investigated the effect of some physicochemical parameters on the removal of ochratoxin A (OTA) by yeasts. Two wild strains of Saccharomyces cerevisiae (W47 and Y28) were used to assess OTA removal under various conditions of temperature, pH, ethanol content and incubation time. All samples were analysed for OTA concentration by enzyme-linked immunosorbent assay (ELISA). In addition, yeast oenological traits were investigated: qualitative and technological traits were assessed on appropriate laboratory media, while the main products of microfermentation (sugars, ethanol, glycerol, acetic acid) were evaluated by Fourier transform infrared spectroscopy (FTIR). The results showed OTA reduction by 36-42% in cultures containing 100 g L⁻¹ ethanol incubated at pH 3.5 and 37 °C. OTA removal was affected by contact time, pH and ethanol content, as it was increased at low pH and by 100 g L⁻¹ ethanol. Moreover, the phenomenon was reversible, as OTA was lowest after 4 days, then it was partially released in the medium. © 2012 Society of Chemical Industry.

Ochratoxin A Detection on Antibody- Immobilized on BSA-Functionalized Gold Electrodes.

PubMed

Badea, Mihaela; Floroian, Laura; Restani, Patrizia; Cobzac, Simona Codruta Aurora; Moga, Marius

2016-01-01

Ochratoxin A (OTA)-a toxin produced by Aspergillus carbonarius, Aspergillus ochraceus, and Penicillium verrucosum-is one of the most-abundant food-contaminating mycotoxins. To avoid the risk of OTA consumption for humans and animals, the rapid detection and quantitation of OTA level in different commodities are of great importance. In this work, an impedimetric immunosensor for ochratoxin A (OTA) detection, a common toxic botanical contaminant, was developed via the immobilization of anti-OTA antibody on bovine serum albumin modified gold electrodes. A four-step reaction protocol was tested to modify the gold electrode and obtain the sensing substrate. All the steps of the immunosensor elaboration and also the immunochemical reaction between surface-bound antibody and ochratoxin A were analyzed using cyclic voltammetry and electrochemical impedance spectroscopy. Modification of the impedance due to the specific antigen-antibody reaction at immunosensor surface, was used in order to detect ochratoxin A. Linear proportionality of the charge transfer resistance to the concentration of OTA allows ochratoxin A detection in the range of 2.5-100 ng/mL.

Gold Nanoparticle-Aptamer-Based LSPR Sensing of Ochratoxin A at a Widened Detection Range by Double Calibration Curve Method

NASA Astrophysics Data System (ADS)

Liu, Boshi; Huang, Renliang; Yu, Yanjun; Su, Rongxin; Qi, Wei; He, Zhimin

2018-04-01

Ochratoxin A (OTA) is a type of mycotoxin generated from the metabolism of Aspergillus and Penicillium, and is extremely toxic to humans, livestock, and poultry. However, traditional assays for the detection of OTA are expensive and complicated. Other than OTA aptamer, OTA itself at high concentration can also adsorb on the surface of gold nanoparticles (AuNPs), and further inhibit AuNPs salt aggregation. We herein report a new OTA assay by applying the localized surface plasmon resonance effect of AuNPs and their aggregates. The result obtained from only one single linear calibration curve is not reliable, and so we developed a “double calibration curve” method to address this issue and widen the OTA detection range. A number of other analytes were also examined, and the structural properties of analytes that bind with the AuNPs were further discussed. We found that various considerations must be taken into account in the detection of these analytes when applying AuNP aggregation-based methods due to their different binding strengths.

Ultrasensitive one-step rapid detection of ochratoxin A by the folding-based electrochemical aptasensor.

PubMed

Wu, Jingjing; Chu, Huaqin; Mei, Zhanlong; Deng, Yi; Xue, Feng; Zheng, Lei; Chen, Wei

2012-11-13

A one-step electrochemical aptasensor using the thiol- and methylene blue- (MB-) dual-labeled aptamer modified gold electrode for determination of ochratoxin A (OTA) was presented in this research. The aptamer against OTA was covalently immobilized on the surface of the electrode by the self-assembly effect and used as recognition probes for OTA detection by the binding induced folding of the aptamer. Under the optimal conditions, the developed electrochemical aptasensor demonstrated a wide linear range from 0.1 pg mL(-1) to 1000 pg mL(-1) with the limit of detection (LOD) of 0.095 pg mL(-1), which was an extraordinary sensitivity compared with other common methods for OTA detection. Moreover, as a practical application, this proposed electrochemical aptasensor was used to monitor the OTA level in red wine samples without any special pretreatment and with satisfactory results obtained. Study results showed that this electrochemical aptasensor could be a potential useful platform for on-site OTA measurement in real complex samples. Copyright © 2012 Elsevier B.V. All rights reserved.

Potential of yeasts isolated from dry-cured ham to control ochratoxin A production in meat models.

PubMed

Peromingo, Belén; Núñez, Félix; Rodríguez, Alicia; Alía, Alberto; Andrade, María J

2018-03-02

The environmental conditions reached during the ripening of dry-cured meat products favour the proliferation of moulds on their surface. Some of these moulds are hazardous to consumers because of their ability to produce ochratoxin A (OTA). Biocontrol using Debaryomyces hansenii could be a suitable strategy to prevent the growth of ochratoxigenic moulds and OTA accumulation in dry-cured meat products. The aim of this work was to evaluate the ability of two strains of D. hansenii to control the growth and OTA production of Penicillium verrucosum in a meat model under water activities (a w ) values commonly reached during the dry-cured meat product ripening. The presence of D. hansenii strains triggered a lengthening of the lag phase and a decrease of the growth rate of P. verrucosum in meat-based media at 0.97 and 0.92 a w . Both D. hansenii strains significantly reduced OTA production (between 85.16 and 92.63%) by P. verrucosum in the meat-based medium at 0.92 a w . Neither absorption nor detoxification of OTA by D. hansenii strains seems to be involved. However, a repression of the expression of the non-ribosomal peptide synthetase (otanpsPN) gene linked to the OTA biosynthetic pathway was observed in the presence of D. hansenii. To confirm the protective role of D. hansenii strains, they were inoculated together with P. verrucosum Pv45 in dry-fermented sausage and dry-cured ham slices. Although P. verrucosum Pv45 counts were not affected by the presence of D. hansenii in both meat matrices, a reduction of OTA amount was observed. Therefore, the effect of D. hansenii strains on OTA accumulation should be attributed to a reduction at transcriptional level. Consequently, native D. hansenii can be useful as biocontrol agent in dry-cured meat products for preventing the hazard associated with the presence of OTA. Copyright © 2018 Elsevier B.V. All rights reserved.

A Label-Free Aptasensor for Ochratoxin a Detection Based on the Structure Switch of Aptamer.

PubMed

Liu, Feng; Ding, Ailing; Zheng, Jiushang; Chen, Jiucun; Wang, Bin

2018-06-01

A label-free sensing platform is developed based on switching the structure of aptamer for highly sensitive and selective fluorescence detection of ochratoxin A (OTA). OTA induces the structure of aptamer, transforms into G-quadruplex and produces strong fluorescence in the presence of zinc(II)-protoporphyrin IX probe due to the specific bind to G-quadruplex. The simple method exhibits high sensitivity towards OTA with a detection limit of 0.03 nM and excellent selectivity over other mycotoxins. In addition, the successful detection of OTA in real samples represents a promising application in food safety.

Approach for ochratoxin A fast screening in spices using clean-up tandem immunoassay columns with confirmation by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).

PubMed

Goryacheva, I Yu; De Saeger, S; Lobeau, M; Eremin, S A; Barna-Vetró, I; Van Peteghem, C

2006-09-01

An approach for ochratoxin A (OTA) fast cost-effective screening based on clean-up tandem immunoassay columns was developed and optimized for OTA detection with a cut-off level of 10 microg kg(-1) in spices. Two procedures were tested and applied for OTA detection. Column with bottom detection immunolayer was optimized for OTA determination in Capsicum ssp. spices. A modified clean-up tandem immunoassay procedure with top detection immunolayer was successfully applied for all tested spices. Its main advantages were decreasing of the number of analysis steps and quantity of antibody and also minimizing of matrix effects. The total duration of the extraction and analysis was about 40 min for six samples. Chilli, red pepper, pili-pili, cayenne, paprika, nutmeg, ginger, white pepper and black pepper samples were analyzed for OTA contamination by the proposed clean-up tandem immunoassay procedures. Clean-up tandem immunoassay results were confirmed by HPLC-MS/MS with immunoaffinity column clean-up. Among 17 tested Capsicum ssp. spices, 6 samples (35%) contained OTA in a concentration exceeding the 10 microg kg(-1) limit discussed by the European Commission. All tested nutmeg (n=8), ginger (n=5), white pepper (n=7) and black pepper (n=6) samples did not contain OTA above this action level.

Role of grapevine vegetative expression on Aspergillus spp. incidence and OTA accumulation in wines produced in a temperate humid climate.

PubMed

Ferrari, Virginia; Dellacassa, Eduardo; Coniberti, Andrés; Disegna, Edgardo

2017-02-01

Aspergillus spp. and Penicillium spp. are the main producers of ochratoxin A (OTA), a mycotoxin responsible for fatal human diseases. Some authorities have established a maximum of 2 μg/L of OTA in wine. Although the incidence and occurrence of OTA in grapes and wine is highly related to climate conditions, as has been extensively documented, there is no conclusive information on the effects of cultivation systems on the presence of OTA. This study focuses on determining the effect of the trellis system, planting density and cordon height on plant microclimate and thus on Aspergillus spp. contamination and OTA production in Tannat wines in Southern Uruguay. Two experiments were conducted during the 2010-2011 growing season: (1) a strip split plot design with five replicates and two cordon heights (CH) (0.5 m and 1.0 m above the soil) were compared in two planting densities (PD) (0.8 and 1.5 m between plants); (2) a randomised complete block design, vertical shoot positioning (VSP) versus Lyra trellis systems were evaluated. The results suggest that, even the macro- and micro-climate growing conditions play an important part in Aspergillus developing on grapes. Agronomical practices also have an undoubted impact on the risk and control of OTA accumulation in wine.

Analyzing Reasons for Non-Adoption of Distance Delivery Formats in Occupational Therapy Assistant (OTA) Education

ERIC Educational Resources Information Center

Gergen, Theresa; Roblyer, M. D.

2013-01-01

Though distance education formats could help address an urgent need for growth in the occupational therapy assistant (OTA) workforce, distance methods are not as accepted in these programs as they are in other professional and clinical programs. This study investigated whether beliefs and levels of experience of OTA program directors shaped their…

Relationship between ecophysiological factors, growth and ochratoxin A contamination of dry-cured sausage based matrices.

PubMed

Rodríguez, Alicia; Capela, Daniela; Medina, Ángel; Córdoba, Juan J; Magan, Naresh

2015-02-02

Dry-cured sausages are colonised by moulds during the ripening process. The temperature and the salt content (which affects water activity, aw) predispose the surface to colonisation by Penicillium species, including Penicillium nordicum and Penicillium verrucosum which can lead to contamination of the sausages with ochratoxin A (OTA). The objective of this work was to obtain scientific data on the impact that interaction between ionic water stress (aw; 0.97, 0.94, 0.90, 0.87 and 0.84) and temperature (30, 25, 20, 15 and 10°C) may have on lag phases prior to growth, growth and OTA production by some P. verrucosum and P. nordicum strains isolated from dry-cured meat products on a dry-cured sausage-based medium over a period of 12days. Although P. nordicum had shorter lag phases than P. verrucosum, the latter grew faster than P. nordicum in most conditions tested. For both species, there was no growth and OTA production at 0.84 aw at all the temperatures tested. The fungi were more tolerant at moderate ionic aw conditions (0.94 and 0.90) and 20 and 25°C. In contrast, the patterns of production of OTA were very different from those for growth. Different OTA production profiles between the two OTA-producing species were found. While P. nordicum began producing OTA in most of the conditions tested by day 6, P. verrucosum only produced the toxin in these conditions when the temperature and aw were >10°C and >0.90, respectively. However, the P. verrucosum strain produced much higher concentrations of OTA than the P. nordicum strain in all conditions. We developed contour maps of the optimum and marginal aw×temperature conditions for growth/OTA production on dry-cured sausage-based medium for the first time. This suggests that these interacting conditions during the early phases of production must be effectively controlled as these favour growth of the toxigenic Penicillia. Knowledge on the ecophysiology of these two important Penicillium species on these matrices could help to make appropriate technological modifications during the sausage ripening process. Thus, our findings may help in informed decision-making in relation to temperature and salt additions at the beginning of processing/curing. Such changes may favour colonisation of starter cultures over OTA producing Penicillia and minimise OTA contamination risks in dry-cured sausages. This may be then effectively incorporated into the hygienic production system in the framework of HACCP. Copyright © 2014 Elsevier B.V. All rights reserved.

Variation in Fumonisin and Ochratoxin Production Associated with Differences in Biosynthetic Gene Content in Aspergillus niger and A. welwitschiae Isolates from Multiple Crop and Geographic Origins

PubMed Central

Susca, Antonia; Proctor, Robert H.; Morelli, Massimiliano; Haidukowski, Miriam; Gallo, Antonia; Logrieco, Antonio F.; Moretti, Antonio

2016-01-01

The fungi Aspergillus niger and A. welwitschiae are morphologically indistinguishable species used for industrial fermentation and for food and beverage production. The fungi also occur widely on food crops. Concerns about their safety have arisen with the discovery that some isolates of both species produce fumonisin (FB) and ochratoxin A (OTA) mycotoxins. Here, we examined FB and OTA production as well as the presence of genes responsible for synthesis of the mycotoxins in a collection of 92 A. niger/A. welwitschiae isolates from multiple crop and geographic origins. The results indicate that (i) isolates of both species differed in ability to produce the mycotoxins; (ii) FB-nonproducing isolates of A. niger had an intact fumonisin biosynthetic gene (fum) cluster; (iii) FB-nonproducing isolates of A. welwitschiae exhibited multiple patterns of fum gene deletion; and (iv) OTA-nonproducing isolates of both species lacked the ochratoxin A biosynthetic gene (ota) cluster. Analysis of genome sequence data revealed a single pattern of ota gene deletion in the two species. Phylogenetic analysis suggest that the simplest explanation for this is that ota cluster deletion occurred in a common ancestor of A. niger and A. welwitschiae, and subsequently both the intact and deleted cluster were retained as alternate alleles during divergence of the ancestor into descendent species. Finally, comparison of results from this and previous studies indicate that a majority of A. niger isolates and a minority of A. welwitschiae isolates can produce FBs, whereas, a minority of isolates of both species produce OTA. The comparison also suggested that the relative abundance of each species and frequency of FB/OTA-producing isolates can vary with crop and/or geographic origin. PMID:27667988

Variation in Fumonisin and Ochratoxin Production Associated with Differences in Biosynthetic Gene Content in Aspergillus niger and A. welwitschiae Isolates from Multiple Crop and Geographic Origins.

PubMed

Susca, Antonia; Proctor, Robert H; Morelli, Massimiliano; Haidukowski, Miriam; Gallo, Antonia; Logrieco, Antonio F; Moretti, Antonio

2016-01-01

The fungi Aspergillus niger and A. welwitschiae are morphologically indistinguishable species used for industrial fermentation and for food and beverage production. The fungi also occur widely on food crops. Concerns about their safety have arisen with the discovery that some isolates of both species produce fumonisin (FB) and ochratoxin A (OTA) mycotoxins. Here, we examined FB and OTA production as well as the presence of genes responsible for synthesis of the mycotoxins in a collection of 92 A. niger/A. welwitschiae isolates from multiple crop and geographic origins. The results indicate that (i) isolates of both species differed in ability to produce the mycotoxins; (ii) FB-nonproducing isolates of A. niger had an intact fumonisin biosynthetic gene (fum) cluster; (iii) FB-nonproducing isolates of A. welwitschiae exhibited multiple patterns of fum gene deletion; and (iv) OTA-nonproducing isolates of both species lacked the ochratoxin A biosynthetic gene (ota) cluster. Analysis of genome sequence data revealed a single pattern of ota gene deletion in the two species. Phylogenetic analysis suggest that the simplest explanation for this is that ota cluster deletion occurred in a common ancestor of A. niger and A. welwitschiae, and subsequently both the intact and deleted cluster were retained as alternate alleles during divergence of the ancestor into descendent species. Finally, comparison of results from this and previous studies indicate that a majority of A. niger isolates and a minority of A. welwitschiae isolates can produce FBs, whereas, a minority of isolates of both species produce OTA. The comparison also suggested that the relative abundance of each species and frequency of FB/OTA-producing isolates can vary with crop and/or geographic origin.

Deleterious Effects of Mycotoxin Combinations Involving Ochratoxin A

PubMed Central

Klarić, Maja Šegvić; Rašić, Dubravka; Peraica, Maja

2013-01-01

Ochratoxin A (OTA) is a nephrotoxic mycotoxin with carcinogenic properties. Its presence was detected in various foodstuffs all over the world but with significantly higher frequency and concentrations in areas with endemic nephropathy (EN). Even though food is often contaminated with more than one mycotoxin, earlier studies focused on the occurrence and toxicology of only OTA. Only a limited number of surveys showed that OTA co-occurs in food with mycotoxins (citrinin-CIT, penicilic acid, fumonisin B1-FB1, aflatoxins-AF) which exert nephrotoxic, carcinogenic or carcinogen-promoting activity. This review summarises the findings on OTA and its co-occurrence with the mentioned mycotoxins in food as well as experimental data on their combined toxicity. Most of the tested mycotoxin mixtures involving OTA produced additive or synergistic effects in experimental models suggesting that these combinations represent a significant health hazard. Special attention should be given to mixtures that include carcinogenic and cancer-promoting mycotoxins. PMID:24189375

Molecularly imprinted polymer-based solid phase clean-up for analysis of ochratoxin A in beer, red wine, and grape juice.

PubMed

Cao, Jiliang; Kong, Weijun; Zhou, Shujun; Yin, Lihui; Wan, Li; Yang, Meihua

2013-04-01

A simple, reliable, and low-cost method based on molecularly imprinted polymer as a selective sorbent of SPE was proposed for the determination of ochratoxin A (OTA) in beer, red wine, and grape juice by HPLC coupled with fluorescence detection (HPLC-FLD). Samples were diluted with water and cleaned up with an AFFINIMIP® SPE OTA column. After washing and eluting, the analyte was analyzed by HPLC-FLD. Under the optimized conditions, LOD and LOQ for OTA were 0.025 and 0.08 ng/mL, respectively. The recoveries of OTA from beer, red wine, and grape spiked at 0.1, 2, and 5 ng/mL ranged from 91.6 to 101.7%. Furthermore, after a simple regenerated procedure, the molecularly imprinted polymer based SPE column could be reused at least 14 times to achieve more than 80% recoveries of OTA in real samples. The developed method was applied to the detection of 30 beer, red wine, and grape juice samples and only four samples were contaminated by OTA with levels below the legal limits. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Differential Adsorption of Ochratoxin A and Anthocyanins by Inactivated Yeasts and Yeast Cell Walls during Simulation of Wine Aging

PubMed Central

Petruzzi, Leonardo; Baiano, Antonietta; De Gianni, Antonio; Sinigaglia, Milena; Corbo, Maria Rosaria; Bevilacqua, Antonio

2015-01-01

The adsorption of ochratoxin A (OTA) by yeasts is a promising approach for the decontamination of musts and wines, but some potential competitive or interactive phenomena between mycotoxin, yeast cells, and anthocyanins might modify the intensity of the phenomenon. The aim of this study was to examine OTA adsorption by two strains of Saccharomyces cerevisiae (the wild strain W13, and the commercial isolate BM45), previously inactivated by heat, and a yeast cell wall preparation. Experiments were conducted using Nero di Troia red wine contaminated with 2 μg/L OTA and supplemented with yeast biomass (20 g/L). The samples were analyzed periodically to assess mycotoxin concentration, chromatic characteristics, and total anthocyanins over 84 days of aging. Yeast cell walls revealed the highest OTA-adsorption in comparison to thermally-inactivated cells (50% vs. 43% toxin reduction), whilst no significant differences were found for the amount of adsorbed anthocyanins in OTA-contaminated and control wines. OTA and anthocyanins adsorption were not competitive phenomena. Unfortunately, the addition of yeast cells to wine could cause color loss; therefore, yeast selection should also focus on this trait to select the best strain. PMID:26516913

Modified magnetic nanoparticles in an electrochemical method for the ochratoxin A determination in Vitis vinifera red grapes tissues.

PubMed

Fernández-Baldo, Martín A; Bertolino, Franco A; Messina, Germán A; Sanz, Maria I; Raba, Julio

2010-12-15

This work described the development and characterization of an electrochemical method using square wave voltammetry (SWV) combined with the use of modified magnetic nanoparticles (MNPs), which had shown a rapid and sensitive determination of ochratoxin A (OTA) in wine grapes (Cabernet Sauvignon, Malbec and Syrah) post-harvest tissues. The wine grapes were inoculated with Aspergillus ochraceus to obtain OTA in artificially infected samples. The OTA was directly determined using square-wave voltammetry. The current obtained is directly proportional to the concentration of OTA present in the samples. This method has been used for OTA determination in wine grapes and it was validated against a commercial ELISA test kit. The limits of detection calculated for electrochemical detection and the ELISA were 0.02 and 1.9 μg kg(-1), respectively and the coefficients of variation for accuracy and precision dates were below 5.5%. This method promises to be suitable for the detection and quantification of OTA in apparently healthy fruits post-harvest for assuring safety and quality of food as well as consumer's health. Copyright © 2010 Elsevier B.V. All rights reserved.

Colorimetric Analysis of Ochratoxin A in Beverage Samples

PubMed Central

Bueno, Diana; Valdez, Luis F.; Gutiérrez Salgado, Juan Manuel; Marty, Jean Louis; Muñoz, Roberto

2016-01-01

This manuscript describes the use of a portable and low cost fluorescence setup to quantify the concentration of ochratoxin A (OTA) in beverage samples using an in-house developed system and different color models. It is reported that OTA is naturally fluorescent, for that reason an ultraviolet light at 365 nm was used to excite the samples and a Complementary Metal Oxide Semiconductor (CMOS) sensor was used to get a photograph of the OTA under excitation conditions, which is controlled by an executable interface designed in MATLAB. For each concentration of OTA, the coordinates with respect to each model color were obtained and plotted to quantify the mycotoxin present in the sample. It was possible to observe that despite the fact no extraction column was employed, the Red, Green, Blue (RGB) model shows a proportional relation to the evaluated concentrations. Despite the fact more analysis and other methods are required to quantify the OTA concentration, the brightness and a,b for the color-opponent dimensions (L*a*b) and Hue, Saturation, Value (HSV) tests provide results whereby it is possible to identify the concentration of OTA in beverage samples such as beer and wine. PMID:27834900

A regeneratable, label-free, localized surface plasmon resonance (LSPR) aptasensor for the detection of ochratoxin A.

PubMed

Park, Jin-Ho; Byun, Ju-Young; Mun, Hyoyoung; Shim, Won-Bo; Shin, Yong-Beom; Li, Taihua; Kim, Min-Gon

2014-09-15

Binding of an analyte on the surface of a nanoparticle typically promotes a change in the local refractive index, which gives rise to a shift in the wavelength of the localized surface plasmon resonance (LSPR) absorption band. The magnitude of the LSPR wavelength change is dependent on both the location of the analyte relative to the surface of the nanoparticle and the degree of alteration of the refractive index. We have employed this phenomenon as the basis for designing a new, label-free approach for the detection of the toxic mold mycotoxin, ochratoxin A (OTA) that employs a gold nanorod (GNR) and an aptamer target binding mechanism. In this system, binding of OTA causes an accumulation of OTA and G-quadruplex structure of the aptamer. This process results in a longitudinal wavelength shift of the LSPR peak associated with a change in the local refractive index near the GNR surface. By using this method, OTA can be quantitatively detected at concentrations lower than 1 nM. In addition, the results of this effort show that aptamer functionalized GNR substrate is robust in that it can be regenerated for reuse over seven times by heating in methanol at 70 °C to remove OTA. Moreover, the proposed biosensor system exhibits high selectivity for OTA over other mycotoxins. Finally, the sensor can be employed to detect OTA in ground corn samples with excellent recovery levels. Copyright © 2014 Elsevier B.V. All rights reserved.

An electrochemical immunosensor for ochratoxin A determination in wines based on a monoclonal antibody and paramagnetic microbeads.

PubMed

Vidal, Juan C; Bonel, Laura; Ezquerra, Alba; Duato, Patricia; Castillo, Juan R

2012-06-01

We report a direct competitive immunosensor for the rapid determination of ochratoxin A (OTA) in wine samples. Magnetic beads (1 ± 0.5 μm diameter) covered with streptavidin were functionalized with a monoclonal antibody against OTA, and then left to incubate in a solution of tracer (ochratoxin conjugated to the enzyme peroxidase) and a range of OTA concentrations (10(-4) to 1,000 ng mL(-1)). After washing and separation steps helped with a magnetic field, a volume of the dispersion was put on screen-printed electrodes under a magnet, and after adding the substrate the p-benzoquinone generated enzymatically was detected by differential-pulse voltammetry. Wine samples (2 mL) were easily prepared simply by adjusting to pH = 7.5 with diluted NaOH and by adding polyvinylpyrrolidone for complexing polyphenols, without any other clean-up or preconcentration steps. The limit of detection for detecting OTA in wines was of 0.11 ± 0.01 ng L(-1), well below the permitted content of the mycotoxin by the European Union (<2 ng mL(-1)). Spiked wines were subjected to immunosensor calibrations to study the matrix effects. OTA concentrations measured with the immunosensor were compared with those obtained by high-performance liquid chromatography coupled to fluorescence detection (AOAC official method 2001.01). The OTA levels from two red wines of "Campo de Borja", Spain, ranged from about 0.027 to 0.033 ng mL(-1) of OTA.

Risk management of ochratoxigenic fungi and ochratoxin A in maize grains by bioactive EVOH films containing individual components of some essential oils.

PubMed

Tarazona, Andrea; Gómez, José V; Gavara, Rafael; Mateo-Castro, Rufino; Gimeno-Adelantado, José V; Jiménez, Misericordia; Mateo, Eva M

2018-03-23

Aspergillus steynii and Aspergillus tubingensis are possibly the main ochratoxin A (OTA) producing species in Aspergillus section Circumdati and section Nigri, respectively. OTA is a potent nephrotoxic, teratogenic, embryotoxic, genotoxic, neurotoxic, carcinogenic and immunosuppressive compound being cereals the first source of OTA in the diet. In this study bioactive ethylene-vinyl alcohol copolymer (EVOH) films containing cinnamaldehyde (CINHO), linalool (LIN), isoeugenol (IEG) or citral (CIT) which are major components of some plant essential oils (EOs) were produced and tested against A. steynii and A. tubingensis growth and OTA production in partly milled maize grains. Due to the favourable safety profile, these bioactive compounds are considered in the category "GRAS". The study was carried out under different water activity (0.96 and 0.99 a w ), and temperature (24 and 32 °C) conditions. ANOVA showed that class of film, fungal species, a w and temperature and their interactions significantly affected growth rates (GR), ED 50 and ED 90 and the doses for total fungal growth inhibition and OTA production. The most effective EVOH films against both species were those containing CINHO. ED 50 , ED 90 and doses for total growth and OTA inhibition were 165-405, 297-614, 333-666 μg of EVOH-CINHO/plate (25 g of maize grains), respectively, depending on environmental conditions. The least efficient were EVOH-LIN films. ED 50 , ED 90 and doses for total growth and OTA inhibition were 2800->3330, >3330 and >3330 μg of EVOH-LIN/plate (25 g of maize grains), respectively. The effectiveness of the bioactive films increased with increasing doses. Overall, A. tubingensis was less sensitive to treatments than A. steynii. Depending on the species, a w and temperature affected GR and OTA production in a different way. In A. steynii cultures, optimal growth occurred at 0.96 a w and 32 °C while optimal OTA production happened at 0.99 a w and 32 °C. In A. tubingensis cultures optimal growth happened at 0.99 a w and 32 °C, although the best conditions for OTA production were 0.99 a w and 24 °C. Thus, these species can be very competitive in warm climates and storage conditions. The EVOH-CINHO films followed by EVOH-IEG and EVOH-CIT films, designed in this study and applied in vapour phase, can be potent antifungal agents against A. steynii and A. tubingensis and strong inhibitors of OTA biosynthesis in maize grains at very low doses. This is the first study on the impact that interacting environmental conditions and bioactive films containing individual components of EOs have on the growth of these ochratoxigenic fungi and on OTA production in maize grains. Copyright © 2018 Elsevier B.V. All rights reserved.

The Effect of Implementing Knowledge Management System in Supplier Selection Content to Improve Learning Performance of Online Travel Agencies Staff

ERIC Educational Resources Information Center

Ariya, Pakinee; Chakpitak, Nopasit; Sureepong, Pradorn

2016-01-01

Supplier selection knowledge of OTAs businesses is one of the most valuable and significant knowledge since OTAs now operate businesses that gain their benefits from having many kinds of tourism products and services for customers to browse from in their own online booking systems. The better the suppliers, the more successful will OTAs be. The…

Impedimetric Aptasensor for Ochratoxin A Determination Based on Au Nanoparticles Stabilized with Hyper-Branched Polymer

PubMed Central

Evtugyn, Gennady; Porfireva, Anna; Stepanova, Veronika; Kutyreva, Marianna; Gataulina, Alfiya; Ulakhovich, Nikolay; Evtugyn, Vladimir; Hianik, Tibor

2013-01-01

An impedimetric aptasensor for ochratoxin A (OTA) detection has been developed on the base of a gold electrode covered with a new modifier consisting of electropolymerized Neutral Red and a mixture of Au nanoparticles suspended in the dendrimeric polymer Botlorn H30®. Thiolated aptamer specific to OTA was covalently attached to Au nanoparticles via Au-S bonding. The interaction of the aptamer with OTA induced the conformational switch of the aptamer from linear to guanine quadruplex form followed by consolidation of the surface layer and an increase of the charge transfer resistance. The aptasensor makes it possible to detect from 0.1 to 100 nM of OTA (limit of detection: 0.02 nM) in the presence of at least 50 fold excess of ochratoxin B. The applicability of the aptasensor for real sample assay was confirmed by testing spiked beer samples. The recovery of 2 nM OTA was found to be 70% for light beer and 78% for dark beer. PMID:24287535

Rapid genome resequencing of an atoxigenic strain of Aspergillus carbonarius

DOE PAGES

Cabañes, F. Javier; Sanseverino, Walter; Castellá, Gemma; ...

2015-03-13

In microorganisms, Ion Torrent sequencing technology has been proved to be useful in whole-genome sequencing of bacterial genomes (5 Mbp). In our study, for the first time we used this technology to perform a resequencing approach in a whole fungal genome (36 Mbp), a non-ochratoxin A producing strain of Aspergillus carbonarius. Ochratoxin A (OTA) is a potent nephrotoxin which is found mainly in cereals and their products, but it also occurs in a variety of common foods and beverages. Due to the fact that this strain does not produce OTA, we focused some of the bioinformatics analyses in genes involvedmore » in OTA biosynthesis, using a reference genome of an OTA producing strain of the same species. This study revealed that in the atoxigenic strain there is a high accumulation of nonsense and missense mutations in several genes. Importantly, a two fold increase in gene mutation ratio was observed in PKS and NRPS encoding genes which are suggested to be involved in OTA biosynthesis.« less

Rapid genome resequencing of an atoxigenic strain of Aspergillus carbonarius

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cabañes, F. Javier; Sanseverino, Walter; Castellá, Gemma

In microorganisms, Ion Torrent sequencing technology has been proved to be useful in whole-genome sequencing of bacterial genomes (5 Mbp). In our study, for the first time we used this technology to perform a resequencing approach in a whole fungal genome (36 Mbp), a non-ochratoxin A producing strain of Aspergillus carbonarius. Ochratoxin A (OTA) is a potent nephrotoxin which is found mainly in cereals and their products, but it also occurs in a variety of common foods and beverages. Due to the fact that this strain does not produce OTA, we focused some of the bioinformatics analyses in genes involvedmore » in OTA biosynthesis, using a reference genome of an OTA producing strain of the same species. This study revealed that in the atoxigenic strain there is a high accumulation of nonsense and missense mutations in several genes. Importantly, a two fold increase in gene mutation ratio was observed in PKS and NRPS encoding genes which are suggested to be involved in OTA biosynthesis.« less

Antifungal and Antiochratoxigenic Activities of Essential Oils and Total Phenolic Extracts: A Comparative Study

PubMed Central

EL Khoury, Rachelle; Atoui, Ali; Mathieu, Florence; Kawtharani, Hiba; EL Khoury, Anthony; Maroun, Richard G.; EL Khoury, Andre

2017-01-01

This study is intended to prevent ochratoxin A (OTA) production by Aspergillus carbonarius S402 using essential oils (EOs) and total phenolic compounds extracted from plants and herbs. The EOs used in this study are the following: bay leaves, cumin, fenugreek, melissa, mint, and sage. As for the phenolic compounds, they were extracted from bay leaves, cumin, fenugreek, melissa, mint, sage, anise, chamomile, fennel, rosemary, and thyme. The experiments were conducted on Synthetic Grape Medium (SGM) medium at 28 °C for 4 days. OTA was extracted from the medium with methanol and quantified using HPLC (High Performance Liquid Chromatography). Results showed that EOs had a greater impact than the total phenolic extracts on the OTA production. Reduction levels ranged between 25% (sage) and 80% (melissa) for the EOs at 5 µL mL−1, and 13% (thyme) and 69% (mint) for the phenolic extracts. Although they did not affect the growth of A. carbonarius, total phenolic extracts and EOs were capable of partially reducing OTA production. Reduction levels depended on the nature of the plants and the concentration of the EOs. Reducing OTA with natural extracts could be a solution to prevent OTA production without altering the fungal growth, thus preserving the natural microbial balance. PMID:28698493

PVP-coated gold nanoparticles for the selective determination of ochratoxin A via quenching fluorescence of the free aptamer.

PubMed

Lv, Lei; Jin, Yongdong; Kang, Xiaojiao; Zhao, Yangyang; Cui, Chengbi; Guo, Zhijun

2018-05-30

This paper describes an aptamer/gold nanoparticle-based assay for ochratoxin A (OTA) detection. This assay is based on the use of an aptamer labeled with carboxyfluorescein (FAM) at its 5'-end and gold nanoparticles (AuNPs) that act as quenchers of fluorescence. When OTA is absent in the system, the fluorescently labeled aptamers are adsorbed on the surface of AuNPs. The fluorescence signal of the fluorescein-labeled OTA aptamer generated is quenched by the fluorescence resonance energy transfer effect of AuNPs. When OTA is present in the system, the fluorescently labeled aptamer binds to OTA and forms a folded structure, which can resist the adsorption of AuNPs. Thus, the fluorescent signal can be retained. The detection limit of this sensing platform is 5 nM, and the linear detection range is 10-1000 nM (R 2  = 0.994). The procedure was validated by the quantitation of OTA in spiked ginger powder samples and were found to be free of interference by the sample matrix. The recoveries and the relative standard deviation varied from 89.0% to 117.8% and from 1.9% to 6.3%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ochratoxin A Contamination of Food from Croatia

PubMed Central

Peraica, Maja; Flajs, Dubravka; Domijan, Ana-Marija; Ivić, Dario; Cvjetković, Bogdan

2010-01-01

Ochratoxin A (OTA) is a mycotoxin with nephrotoxic, genotoxic and carcinogenic properties produced by Penicillium and Aspergillus moulds under different climatic conditions. Humans and animals are exposed to this compound mainly via ingestion of contaminated food. In Croatia, research on mycotoxins focused on OTA when the mycotoxin theory of endemic nephropathy (EN) was postulated. Ochratoxin A was more frequent and at higher concentration in foods from EN than those from the control regions. Subsequently, OTA concentrations were determined in some commodities intended for human consumption such as maize, wheat, beans and wine. Samples from all parts of Croatia were analyzed and OTA was found in all types of commodities. It was frequently found together with other mycotoxins (fumonisin B1, fumonisin B2 and zearalenone). In general, OTA concentration in foods from Croatia is low, but the frequency of positive samples shows considerable variations from year to year depending also on sampling location. Although low levels of OTA were found in a large proportion of analyzed food samples, its persistent co-occurrence with other significant mycotoxins should raise serious public health concerns as there interactions may be synergistic or additive in causing toxicity in humans and animals. There is need to establish control measures through which such contaminations in foods can be managed. PMID:22069674

Application of isotope dilution mass spectrometry: determination of ochratoxin A in the Canadian Total Diet Study

PubMed Central

Tam, J.; Pantazopoulos, P.; Scott, P.M.; Moisey, J.; Dabeka, R.W.; Richard, I.D.K.

2011-01-01

Analytical methods are generally developed and optimized for specific commodities. Total Diet Studies, representing typical food products ‘as consumed’, pose an analytical challenge since every food product is different. In order to address this technical challenge, a selective and sensitive analytical method was developed suitable for the quantitation of ochratoxin A (OTA) in Canadian Total Diet Study composites. The method uses an acidified solvent extraction, an immunoaffinity column (IAC) for clean-up, liquid chromatography-tandem mass spectrometry (LC-MS/MS) for identification and quantification, and a uniformly stable isotope-labelled OTA (U-[13C20]-OTA) as an internal recovery standard. Results are corrected for this standard. The method is accurate (101% average recovery) and precise (5.5% relative standard deviation (RSD)) based on 17 duplicate analysis of various food products over 2 years. A total of 140 diet composites were analysed for OTA as part of the Canadian Total Diet Study. Samples were collected at retail level from two Canadian cities, Quebec City and Calgary, in 2008 and 2009, respectively. The results indicate that 73% (102/140) of the samples had detectable levels of OTA, with some of the highest levels of OTA contamination found in the Canadian bread supply. PMID:21623499

Estimated exposure to zearalenone, ochratoxin A and aflatoxin B1 through the consume of bakery products and pasta considering effects of food processing.

PubMed

Bol, Emilli Keller; Araujo, Letícia; Veras, Flávio Fonseca; Welke, Juliane Elisa

2016-03-01

The objective of this research was to estimate the processing effect on mycotoxins levels and the exposure to zearalenone (ZEA), ochratoxin (OTA) and aflatoxin B1 (AFB1) through the consumption of pasta and bakery products. The higher reduction percentage of mycotoxins was observed in cake production (95, 90 and 70% for ZEA, OTA and AFB1, respectively). Bread and biscuit showed similar reduction in mycotoxins levels (89 and 90% for ZEA; 80 and 85% for OTA; 36 and 40% for AFB1, respectively). The lower reduction in the levels of mycotoxins has been observed for pasta (75, 65 and 10% for ZEA, OTA and AFB1, respectively). The consumption of these products could represent 12.6% of the maximum tolerable daily intake of ZEA and 30.5% of the tolerable weekly intake of OTA. The margin of exposure value related to the exposure to AFB1 was 24.6. The exposure to ZEA and OTA through the consumption of bakery products and pasta would not represent risk for consumer health, (although conjugated forms were not determined). However, the exposure to AFB1 represents a risk (even without considering the AFB1-conjugated forms). Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of potassium sorbate (E-202) and the antifungal PgAFP protein on Aspergillus carbonarius growth and ochratoxin A production in raisin simulating media.

PubMed

Fodil, Sihem; Delgado, Josué; Varvaro, Leonardo; Yaseen, Thaer; Rodríguez, Alicia

2018-05-13

Ochratoxin A (OTA) is a mycotoxin produced by several species of Aspergillus and Penicillium fungi. The presence of OTA in raisins is mainly related to the black Aspergillus spp. contamination. This toxin poses risks to human and animal health due to their high toxicity and carcinogenicity. Therefore, new strategies to avoid the risk associated to OTA are necessary. In the present study, a comparison between the effects of the antifungal protein PgAFP and potassium sorbate (E-202), on the growth of Aspergillus carbonarius, biosynthetic- and stress-related gene expression and its OTA production at two water activity (a w ) levels 0.95 and 0.93 a w , was carried out. The results showed that PgAFP successfully controlled OTA production, whereas E-202, although was able to decrease Aspergillus carbonarius growth, caused a significant increase in OTA production by the fungus. PgAFP protein, a biological compound with an antifungal activity, is safer to use compared to E-202 and may be proposed as a food preservative and a useful biocontrol strategy to control ochratoxigenic A. carbonarius in raisins. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Overexpression of pig selenoprotein S blocks OTA-induced promotion of PCV2 replication by inhibiting oxidative stress and p38 phosphorylation in PK15 cells.

PubMed

Gan, Fang; Hu, Zhihua; Huang, Yu; Xue, Hongxia; Huang, Da; Qian, Gang; Hu, Junfa; Chen, Xingxiang; Wang, Tian; Huang, Kehe

2016-04-12

Porcine circovirus type 2 (PCV2) is the primary cause of porcine circovirus disease, and ochratoxin A (OTA)-induced oxidative stress promotes PCV2 replication. In humans, selenoprotein S (SelS) has antioxidant ability, but it is unclear whether SelS affects viral infection. Here, we stably transfected PK15 cells with pig pCDNA3.1-SelS to overexpress SelS. Selenium (Se) at 2 or 4 μM and SelS overexpression blocked the OTA-induced increases of PCV2 DNA copy number and infected cell numbers. SelS overexpression also increased glutathione (GSH), NF-E2-related factor 2 (Nrf2) mRNA, and γ-glutamyl-cysteine synthetase mRNA levels; decreased reactive oxygen species (ROS) levels; and inhibited p38 phosphorylation in PCV2-infected PK15 cells, regardless of OTA treatment. Buthionine sulfoximine reversed all of the above SelS-induced changes. siRNA-mediated SelS knockdown decreased Nrf2 mRNA and GSH levels, increased ROS levels, and promoted PCV2 replication in OTA-treated PK15 cells. These data indicate that pig SelS blocks OTA-induced promotion of PCV2 replication by inhibiting the oxidative stress and p38 phosphorylation in PK15 cells.

Overexpression of pig selenoprotein S blocks OTA-induced promotion of PCV2 replication by inhibiting oxidative stress and p38 phosphorylation in PK15 cells

PubMed Central

Gan, Fang; Hu, Zhihua; Huang, Yu; Xue, Hongxia; Huang, Da; Qian, Gang; Hu, Junfa; Chen, Xingxiang; Wang, Tian; Huang, Kehe

2016-01-01

Porcine circovirus type 2 (PCV2) is the primary cause of porcine circovirus disease, and ochratoxin A (OTA)-induced oxidative stress promotes PCV2 replication. In humans, selenoprotein S (SelS) has antioxidant ability, but it is unclear whether SelS affects viral infection. Here, we stably transfected PK15 cells with pig pCDNA3.1-SelS to overexpress SelS. Selenium (Se) at 2 or 4 μM and SelS overexpression blocked the OTA-induced increases of PCV2 DNA copy number and infected cell numbers. SelS overexpression also increased glutathione (GSH), NF-E2-related factor 2 (Nrf2) mRNA, and γ-glutamyl-cysteine synthetase mRNA levels; decreased reactive oxygen species (ROS) levels; and inhibited p38 phosphorylation in PCV2-infected PK15 cells, regardless of OTA treatment. Buthionine sulfoximine reversed all of the above SelS-induced changes. siRNA-mediated SelS knockdown decreased Nrf2 mRNA and GSH levels, increased ROS levels, and promoted PCV2 replication in OTA-treated PK15 cells. These data indicate that pig SelS blocks OTA-induced promotion of PCV2 replication by inhibiting the oxidative stress and p38 phosphorylation in PK15 cells. PMID:26943035

Cross-reactivity of antibodies with phenolic compounds in pistachios during quantification of ochratoxin A by commercial enzyme-linked immunosorbent assay kits.

PubMed

Lee, Hyun Jung; Meldrum, Alexander D; Rivera, Nicholas; Ryu, Dojin

2014-10-01

Ochratoxin A (OTA), a nephrotoxic mycotoxin, naturally occurs in wide range of agricultural commodities. Typical screening of OTA involves various enzyme-linked immunosorbent assay (ELISA) methods. Pistachio (Pistacia vera L.) is a rich source of phenolic compounds that may result in a false positive due to structural similarities to OTA. The present study investigated the cross-reactivity profiles of phenolic compounds using two commercial ELISA test kits. High-performance liquid chromatography was used to confirm the concentration of OTA in the pistachio samples and compared with the results obtained from ELISA. When the degree of interaction and 50 % inhibitory concentration of phenolic compounds were determined, the cross-reactivity showed a pattern similar to that observed with the commercial ELSIA kits, although quantitatively different. In addition, the degree of interaction increased with the increasing concentration of phenolic compounds. The ELISA value had stronger correlations with the content of total phenolic compound, gallic acid, and catechin (R(2) = 0.757, 0.732, and 0.729, respectively) compared with epicatechin (R(2) = 0.590). These results suggest that phenolic compounds in pistachio skins may cross-react with the OTA antibody and lead to a false positive or to an overestimation of OTA concentration in ELISA-based tests.

Occurrence of ochratoxin A in spices commercialized in Abidjan (Côte d'Ivoire).

PubMed

Manda, Pierre; Adanou, Ketty Michele; Ardjouma, Dembelé; Adepo, Aholia Jean Baptiste; Dano, Djédjé Sébastien

2016-08-01

Ochratoxin A (OTA) is a mycotoxin produced mostly by several species of Aspergillus and Penicillium. OTA is nephrotoxic in all animal species in which it has been tested and is cancerogenic in rodents. It is associated with Balkan endemic nephropathy. It is naturally present in many crop products such as cereals (barley, wheat, maize) and dried fruits, spices, coffee, wine, olives, and cocoa. The aim of this study was to assess the contamination of three Ivoirian spices with OTA (ginger, chili, and pepper) widely consumed by the population. A total of 90 spice samples (ginger: n = 30; chili: n = 30; pepper n = 30) was taken from various sales outlets of Abidjan. OTA was quantified using an HPLC apparatus coupled with a fluorimetric detector. The chili and ginger samples were contaminated with OTA at a mean concentration of 57.48 ± 174 and 0.12 ± 0.15 μg/kg, respectively. No contamination of the pepper samples was detected. Eight (26.67 %) of the chili samples exceeded the maximum limit of 15 μg/kg established by European regulation. These results should serve as an alert on the risk to the consumer population of these products that are highly contaminated with OTA.

Combination of Metagenomics and Culture-Based Methods to Study the Interaction Between Ochratoxin A and Gut Microbiota

PubMed Central

Guo, Mingzhang; Huang, Kunlun; Chen, Siyuan; Qi, Xiaozhe; He, Xiaoyun; Cheng, Wen-Hsing; Luo, Yunbo; Xia, Kai; Xu, Wentao

2014-01-01

Gut microbiota represent an important bridge between environmental substances and host metabolism. Here we reported a comprehensive study of gut microbiota interaction with ochratoxin A (OTA), a major food-contaminating mycotoxin, using the combination of metagenomics and culture-based methods. Rats were given OTA (0, 70, or 210 μg/kg body weight) by gavage and fecal samples were collected at day 0 and day 28. Bacterial genomic DNA was extracted from the fecal samples and both 16S rRNA and shotgun sequencing (two main methods of metagenomics) were performed. The results indicated OTA treatment decreased the within-subject diversity of the gut microbiota, and the relative abundance of Lactobacillus increased considerably. Changes in functional genes of gut microbiota including signal transduction, carbohydrate transport, transposase, amino acid transport system, and mismatch repair were observed. To further understand the biological sense of increased Lactobacillus, Lactobacillus selective medium was used to isolate Lactobacillus species from fecal samples, and a strain with 99.8% 16S rRNA similarity with Lactobacillus plantarum strain PFK2 was obtained. Thin-layer chromatography showed that this strain could absorb but not degrade OTA, which was in agreement with the result in metagenomics that no genes related to OTA degradation increased. In conclusion, combination of metagenomics and culture-based methods can be a new strategy to study intestinal toxicity of toxins and find applicable bacterial strains for detoxification. When it comes to OTA, this kind of mycotoxin can cause compositional and functional changes of gut microbiota, and Lactobacillus are key genus to detoxify OTA in vivo. PMID:24973096

Effects of feeding bentonite clay upon ochratoxin A-induced immunosuppression in broiler chicks.

PubMed

Khatoon, Aisha; Khan, Muhammad Zargham; Abidin, Zain Ul; Bhatti, Sheraz Ahmed

2018-03-01

A presence of mycotoxins in feed is one of the most alarming issues in the poultry feed industry. Ochratoxins, produced by several Aspergillus and Penicillium species, are important mycotoxin regarding the health status of poultry birds. Ochratoxins are further classified into to several subtypes (A, B, C, etc) depending on their chemical structures, but ochratoxin A (OTA) is considered the most important and toxic. Bentonite clay, belonging to phyllosilicates and formed from weathering of volcanic ashes, has adsorbent ability for several mycotoxins. The present study was designed to study the effects of bentonite clay upon OTA-induced immunosuppression in broiler chicks. For this, 480 day-old broiler chicks were procured from a local hatchery and then different combinations of OTA (0.15, 0.3, or 1.0 mg/kg) and bentonite clay (5, 10, and 20 g/kg) were incorporated into their feed. At 13, 30, and 42 days of age, parameters such as antibody responses to sheep red blood cells, in situ lymphoproliferative responses to mitogen (PHA-P), and in situ phagocytic activity (i.e., via carbon clearance) were determined respectively. The results indicated there was a significant reduction of total antibody and immunoglobulin titres, lymphoproliferative responses, and phagocytic potential in OTA-treated birds, suggesting clear immunosuppression by OTA in birds in a dose-dependent manner. These results were also significantly lower in all combination groups (OTA with bentonite clay), suggesting few to no effects of feeding bentonite clay upon OTA- induced alterations in different immune parameters.

Homogeneous electrochemical detection of ochratoxin A in foodstuff using aptamer-graphene oxide nanosheets and DNase I-based target recycling reaction.

PubMed

Sun, Ai-Li; Zhang, Yan-Fang; Sun, Guo-Peng; Wang, Xuan-Nian; Tang, Dianping

2017-03-15

A simple and feasible homogeneous electrochemical sensing protocol was developed for the detection of ochratoxin A (OTA) in foodstuff on the immobilization-free aptamer-graphene oxide nanosheets coupling with DNase I-based cycling signal amplification. Thionine-labeled OTA aptamers were attached to the surface of nanosheets because of the strong noncovalent binding of graphene oxide nanosheets with nucleobases and aromatic compounds. The electronic signal was acquired via negatively charged screen-printed carbon electrode (SPCE) toward free thionine molecules. Initially, the formed thionine-aptamer/graphene nanocomposites were suspended in the detection solution and far away from the electrode, thereby resulting in a weak electronic signal. Upon addition of target OTA, the analyte reacted with the aptamer and caused the dissociation of thionine-aptamer from the graphene oxide nanosheets. The newly formed thionine-aptamer/OTA could be readily cleaved by DNase I and released target OTA, which could retrigger thionine-aptamer/graphene nanocomposites with target recycling to generate numerous free thionine molecules. Free thionine molecules were captured by negatively charged SPCE, each of which could produce an electrochemical signal within the applied potentials. Under optimal conditions, graphene-based aptasensing platform could exhibit good electrochemical responses for the detection of OTA at a concentration as low as 5.6pg/mL. The reproducibility, precision and selectivity of the system were acceptable. Importantly, the method accuracy was comparable with commercialized OTA ELISA kit when using for quantitative monitoring of contaminated wheat samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Exposure assessment to ochratoxin A in Chinese wine.

PubMed

Zhong, Qi Ding; Li, Guo Hui; Wang, Dao Bing; Shao, Yi; Li, Jing Guang; Xiong, Zheng He; Wu, Yong Ning

2014-09-03

A rapid, sensitive, reproducible, and inexpensive method of high-performance liquid chromatography with fluorescence detection after an anion-exchange solid-phase extraction cleanup step for the analysis of ochratoxin A (OTA) in Chinese wine was developed. The average recovery rate and the average RSD of recovery were 97.47% and about 4%. The relative standard deviations of both the interday and intraday precision were 6.7 and 12.6%, respectively. The limits of detection and quantitation were determined to be 0.01 and 0.03 μg/L, respectively. A total of 223 samples from the major wine-producing areas of China were analyzed for OTA. OTA was detected at levels of 0.01-0.98 μg/L. The mean was 0.15 μg/L. Then, participants as representative inhabitants were invited to answer the designed questionnaire about the quantity and frequency of wine consumption. All data were simulated by the point evaluation for the risk assessment of OTA contamination from wine. Those results indicated that daily intake (DI) of OTA for the average adult consumer varies between 0.86 and 1.08 ng/kg bw per week, which was lower than all the reference standards. However, the DI value (4.38-5.54 ng/kg bw per week) in the high percentile (97.5) was slightly above 5% PTWI (100 ng kg(-1) week(-1)) of the JECFA. In conclusion, OTA exposure from Chinese wine has no risk of harm. This research will provide the scientific basis for determining the maximum limit of OTA content in Chinese wine.

Content Validation and Evaluation of an Endovascular Teamwork Assessment Tool.

PubMed

Hull, L; Bicknell, C; Patel, K; Vyas, R; Van Herzeele, I; Sevdalis, N; Rudarakanchana, N

2016-07-01

To modify, content validate, and evaluate a teamwork assessment tool for use in endovascular surgery. A multistage, multimethod study was conducted. Stage 1 included expert review and modification of the existing Observational Teamwork Assessment for Surgery (OTAS) tool. Stage 2 included identification of additional exemplar behaviours contributing to effective teamwork and enhanced patient safety in endovascular surgery (using real-time observation, focus groups, and semistructured interviews of multidisciplinary teams). Stage 3 included content validation of exemplar behaviours using expert consensus according to established psychometric recommendations and evaluation of structure, content, feasibility, and usability of the Endovascular Observational Teamwork Assessment Tool (Endo-OTAS) by an expert multidisciplinary panel. Stage 4 included final team expert review of exemplars. OTAS core team behaviours were maintained (communication, coordination, cooperation, leadership team monitoring). Of the 114 OTAS behavioural exemplars, 19 were modified, four removed, and 39 additional endovascular-specific behaviours identified. Content validation of these 153 exemplar behaviours showed that 113/153 (73.9%) reached the predetermined Item-Content Validity Index rating for teamwork and/or patient safety. After expert team review, 140/153 (91.5%) exemplars were deemed to warrant inclusion in the tool. More than 90% of the expert panel agreed that Endo-OTAS is an appropriate teamwork assessment tool with observable behaviours. Some concerns were noted about the time required to conduct observations and provide performance feedback. Endo-OTAS is a novel teamwork assessment tool, with evidence for content validity and relevance to endovascular teams. Endo-OTAS enables systematic objective assessment of the quality of team performance during endovascular procedures. Copyright © 2016. Published by Elsevier Ltd.

Holding the Edge: Maintaining the Defense Technology Base

DTIC Science & Technology

1989-04-01

report. OTA assumes full responsibility for the report and the accuracy of its contents . tv OTA Project Staff-Defense Technology Base Lionel S. Johns...necessarily approve, disapprove, or endorse this report. OTA assumes full responsibility for the report and the accuracy of its contents . vii • L ,1 Contents ...along with original research contractors) having to buy from companies that and analysis . Moreover, while DoD management do not need its business

Reduction of Ochratoxin A in Oat Flakes by Twin-Screw Extrusion Processing.

PubMed

Lee, Hyun Jung; Dahal, Samjhana; Perez, Enrique Garcia; Kowalski, Ryan Joseph; Ganjyal, Girish M; Ryu, Dojin

2017-10-01

Ochratoxin A (OTA) is one of the most important mycotoxins owing to its widespread occurrence and toxicity, including nephrotoxicity and potential carcinogenicity to humans. OTA has been detected in a wide range of agricultural commodities, including cereal grains and their processed products. In particular, oat-based products show a higher incidence and level of contamination. Extrusion cooking is widely used in the manufacturing of breakfast cereals and snacks and may reduce mycotoxins to varying degrees. Hence, the effects of extrusion cooking on the stability of OTA in spiked (100 μg/kg) oat flake was investigated by using a laboratory-scale twin-screw extruder with a central composite design. Factors examined were moisture content (20, 25, and 30% dry weight basis), temperature (140, 160, and 180°C), screw speed (150, 200, and 250 rpm), and die size (1.5, 2, and 3 mm). Both nonextruded and extruded samples were analyzed for reductions of OTA by high-performance liquid chromatography, coupled with fluorescence detection. The percentage of reductions in OTA in the contaminated oat flakes upon extrusion processing were in the range of 0 to 28%. OTA was partially stable during extrusion, with only screw speed and die size having significant effect on reduction (P < 0.005). The highest reduction of 28% was achieved at 180°C, 20% moisture, 250 rpm screw speed, and a 3-mm die with 193 kJ/kg specific mechanical energy. According to the central composite design analyses, up to 28% of OTA can be reduced by a combination of 162°C, 30% moisture, and 221 rpm, with a 3-mm die.

Post-harvest practices linked with ochratoxin A contamination of coffee in three provinces of Cordillera Administrative Region, Philippines.

PubMed

Barcelo, Jonathan M; Barcelo, Racquel C

2018-02-01

One of the emerging concerns in the Cordillera Administrative Region, Philippines is ochratoxin A (OTA) contamination in coffee. During 2015 to 2016, a total of 51 Arabica (Coffea arabica) coffee samples from Benguet province and 71 Robusta (Coffea canephora var. Robusta) coffee samples from the provinces of Ifugao and Kalinga were analysed for OTA contamination. The OTA-producing fungal contaminants during drying and storage of Arabica and Robusta coffee were Aspergillus niger and Aspergillus ochraceus. Ochratoxin A was more commonly detected in Robusta coffee (36.6%) than in Arabica coffee (21.6%). Among the contaminated samples, Robusta coffee cherries in the drying yard had the highest mean OTA level (120.2 μg kg -1 , n = 10) while roasted Robusta coffee beans had the lowest mean level (4.8 μg kg -1 , n = 9). The onset of contamination of Arabica coffee occurred during storage, with a mean OTA level of 46.7 μg kg -1 (n = 9). Roasted coffee had lower OTA content although five samples had levels >5.0 μg kg -1 . Pearson Chi-square analysis (χ 2 ) and Fisher's exact test revealed that several post-harvest practices involving non-removal of the husk or hull and mixing of defective coffee were significantly associated with the occurrence of OTA during drying and storage (p < 0.05). No significant associations, however, were identified during roasting. This study suggests that the post-harvest practices in Cordillera Administrative Region should focus on the removal of defective coffee in all stages of post-harvest and rapid reduction of moisture content particularly during drying.

Mycotoxin co-occurrence in rice, oat flakes and wheat noodles used as staple foods in Ecuador.

PubMed

Ortiz, Johana; Van Camp, John; Mestdagh, Frédéric; Donoso, Silvana; De Meulenaer, Bruno

2013-01-01

The co-occurrence of aflatoxin B₁ (AFB₁), B₂ (AFB₂), G₁ (AFG₁) and G₂ (AFG₂), ochratoxin A (OTA), deoxynivalenol (DON), fumonisin B₁ (FB₁), zearalenone (ZEN), and HT-2 and T-2 toxins in the main Ecuadorian staple cereals (rice, oat flakes, and yellow and white wheat noodles) was evaluated. A ultra high performance liquid chromatography/time-of-flight mass spectrometry (UHPLC/TOFMS) method was developed and validated to screen for the presence of these mycotoxins in those cereal matrices. Matrix-matched calibration curves were used to compensate for ion suppression and extraction losses and the recovery values were in agreement with the minimum requirements of Regulation 401/2006/EC (70-110%). For most mycotoxins, the LODs obtained allowed detection in compliance with the maximum permitted levels set in Regulation EC/2006/1881, with the exception of OTA in all cereals and AFB1 in yellow noodles. Extra target analysis of OTA in oat flakes and wheat noodles was performed by HPLC with fluorescence detection. High rates of contamination were observed in paddy rice (23% DON, 23% FB₁, 7% AFB₁, 2% AFG₁ and 2% AFG₂), white wheat noodles (33% DON and 5% OTA) and oat flakes (17% DON, 2% OTA and 2% AFB₁), whereas the rates of contamination were lower in polished rice (2% AFG₁ and 4% HT-2 toxin) and yellow noodles (5% DON). Low rates of co-occurrence of several mycotoxins were observed only for white wheat noodles (5%) and paddy rice (7%). White noodles were contaminated with DON and/or OTA, while combinations of AFG₁, AFB₁, DON and FB₁ were found in paddy rice. Yellow noodles were contaminated with DON only; oat flakes contained DON, OTA or AFB₁, and polished rice was contaminated with AFG₁ and HT-2 toxin.

Exposure risk assessment to ochratoxin A through consumption of juice and wine considering the effect of steam extraction time and vinification stages.

PubMed

Dachery, Bruna; Veras, Flávio Fonseca; Dal Magro, Lucas; Manfroi, Vitor; Welke, Juliane Elisa

2017-11-01

The goals of this study were (i) to verify the effect of steam extraction used in juice production and the stages of vinification on the ochratoxin A (OTA) levels found in grapes naturally contaminated, and (ii) evaluate the risk of exposure to this toxin when the daily consumption of juice and wine is followed to prevent cardiovascular disease. OTA-producing fungi were isolated from Cabernet Sauvignon, Moscato Itálico and Concord grapes harvested from the same vineyard and intended to produce red wine, white wine and juice, respectively. The highest levels of this toxin were found in the Concord grapes used for juice production. Although greater reduction in OTA levels occurred during juice production (73%) compared to winemaking (66 and 44%, for red and white, respectively), the estimated OTA exposure through juice was higher than the tolerable intake established for this toxin by JECFA. The risk associated with juice consumption, rather than wine, can be explained by (i) higher OTA levels found in Concord must than those of Cabernet and Moscato, indicating that Concord grapes appear to be more susceptible to OTA production by toxigenic fungi; and (ii) the daily recommended juice consumption is higher than those proposed to red wine. Copyright © 2017 Elsevier Ltd. All rights reserved.

1H NMR Spectroscopy-Based Metabolomic Assessment of Uremic Toxicity, with Toxicological Outcomes, in Male Rats Following an Acute, Mid-Life Insult from Ochratoxin A

PubMed Central

Mantle, Peter G.; Nicholls, Andrew W.; Shockcor, John P.

2011-01-01

Overt response to a single 6.25 mg dose of ochratoxin A (OTA) by oral gavage to 15 months male rats was progressive loss of weight during the following four days. Lost weight was restored within one month and animals had a normal life-span without OTA-related terminal disease. Decline in plasma OTA concentration only commenced four days after dosing, while urinary excretion of OTA and ochratoxin alpha was ongoing. During a temporary period of acute polyuria, a linear relationship between urine output and creatinine concentration persisted. Elimination of other common urinary solutes relative to creatinine was generally maintained during the polyuria phase, except that phosphate excretion increased temporarily. 1H NMR metabolomic analysis of urine revealed a progressive cyclic shift in the group principal components data cluster from before dosing, throughout the acute insult phase, and returning almost completely to normality when tested six months later. Renal insult by OTA was detected by 1H NMR within a day of dosing, as the most sensitive early indicator. Notable biomarkers were trimethylamine N-oxide and an aromatic urinary profile dominated by phenylacetylglycine. Tolerance of such a large acute insult by OTA, assessed by rat natural lifetime outcomes, adds a new dimension to toxicology of this xenobiotic. PMID:22069722

Determination of ochratoxin A in wine by means of immunoaffinity and aminopropyl solid-phase column cleanup and fluorometric detection.

PubMed

Longobardi, Francesco; Iacovelli, Vito; Catucci, Lucia; Panzarini, Giuseppe; Pascale, Michelangelo; Visconti, Angelo; Agostiano, Angela

2013-02-27

A new analytical method for the determination of ochratoxin A (OTA) in red wine has been developed by using a double-extract cleanup and a fluorometric measurement after spectral deconvolution. Wine samples were diluted with a solution containing 1% polyethylene glycol and 5% sodium hydrogencarbonate, filtered, and purified by immunoaffinity and aminopropyl solid-phase column. OTA contents in the purified extract were determined by a spectrofluorometer (excitation wavelength, 330 nm; emission wavelength, 470 nm) after deconvolution of fluorescence spectra. Average recoveries from wine samples spiked with OTA at levels ranging from 0.5 to 3.0 ng/mL were 94.5-105.4% with relative standard deviations (RSD) of <15% (n = 4). The limit of detection (LOD) was 0.2 ng/mL, and the total time of analysis was 30 min. The developed method was tested on 18 red wine samples (naturally contaminated and spiked with OTA at levels ranging from 0.4 to 3.0 ng/mL) and compared with AOAC Official Method 2001.01, based on immunoaffinity column cleanup and HPLC with fluorescence detector. A good correlation (r(2) = 0.9765) was observed between OTA levels obtained with the two methods, highlighting the reliability of the proposed method, the main advantage of which is the simple OTA determination by a benchtop fluorometer with evident reductions of cost and time of analysis.

Biocontrol activity of four non- and low-fermenting yeast strains against Aspergillus carbonarius and their ability to remove ochratoxin A from grape juice.

PubMed

Fiori, Stefano; Urgeghe, Pietro Paolo; Hammami, Walid; Razzu, Salvatorico; Jaoua, Samir; Migheli, Quirico

2014-10-17

Aspergillus spp. infection of grape may lead to ochratoxin A (OTA) contamination in processed beverages such as wine and grape juice. The aim of the current study was to evaluate the biocontrol potential of two non-fermenting (Cyberlindnera jadinii 273 and Candida friedrichii 778) and two low-fermenting (Candida intermedia 235 and Lachancea thermotolerans 751) yeast strains against the pathogenic fungus and OTA-producer Aspergillus carbonarius, and their ability to remove OTA from grape juice. Two strains, 235 and 751, showed a significant ability to inhibit A. carbonarius both on grape berries and in in vitro experiments. Neither their filtrate nor their autoclaved filtrate culture broth was able to prevent consistently pathogen growth. Volatile organic compounds (VOCs) produced by all four selected yeasts were likely able to consistently prevent pathogen sporulation in vitro. VOCs produced by the non-fermenting strain 778 also significantly reduced A. carbonarius vegetative growth. Three yeast strains (235, 751, and 778) efficiently adsorbed artificially spiked OTA from grape juice, while autoclaving treatment improved OTA adsorption capacity by all the four tested strains. Biological control of A. carbonarius and OTA-decontamination using yeast is proposed as an approach to meet the Islamic dietary laws concerning the absence of alcohol in halal beverages. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Transfer of ochratoxin A from raw black tea to tea infusions prepared according to the Turkish tradition.

PubMed

Toman, Jakub; Malir, Frantisek; Ostry, Vladimir; Kilic, Mehmet Akif; Roubal, Tomas; Grosse, Yann; Pfohl-Leszkowicz, Annie

2018-01-01

Ochratoxin A (OTA) is a natural contaminant of food including tea with multiple toxic effects, which poses a threat to human health. In terms of lifestyle, the Turkish population is a frequent visitor of tearooms, and the traditional Turkish tea preparation is one of the most popular ways of preparing tea infusion. The aim of this study was to investigate OTA transfer from raw black tea to the tea infusion prepared according to the Turkish tradition. A high-performance liquid chromatography method with a limit of quantification of 0.35 ng g -1 was used for OTA determination. The OTA amount in raw black teas from Turkey ranged from ≤0.35 ng g -1 up to 56.7 ng g -1 . An homogenised sample of black tea naturally contaminated with 55.0 ng g -1 was used to prepare infusions. The OTA transfer from the black tea to the infusion was found to be 41.5% ± 7%. These data are important for the realisation of a 'Total Diet study' (TDS). The TDS can be a complementary tool to estimate the population dietary exposure to OTA across the entire diet by analysing main foods prepared 'as consumed' (tea infusions) and not 'as purchased' (raw tea). © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Decontamination of poultry feed from ochratoxin A by UV and sunlight radiations.

PubMed

Ameer Sumbal, Gul; Hussain Shar, Zahid; Hussain Sherazi, Syed Tufail; Sirajuddin; Nizamani, Shafi Muhammad; Mahesar, Safaraz Ahmed

2016-06-01

Mycotoxin-contaminated feed is very dangerous for the growth and even life of poultry. The objective of the current study was to investigate the efficacy of ultra-violet irradiation for decontamination of ochratoxin A (OTA) in spiked and naturally contaminated poultry feed samples. Spiked and naturally contaminated feed samples were irradiated with ultra-violet light (UV) at distance of 25 cm over the feed samples. In vitro, the effect of UV intensity (0.1 mW cm(-2) at 254 nm UV-C) on different types of poultry feeds contaminated with OTA was evaluated. The same samples were also irradiated with sunlight and analysed for OTA by an indirect enzyme linked immunosorbent assay method. Poultry feed samples containing 500 µg kg(-1) were 100% decontaminated in 180 min with UV radiation while OTA was decreased to 70-95 µg kg(-1) using the same poultry feed samples after 8 h sunlight irradiation. Therefore, UV light was found to be more effective. Only 1 h of UV irradiation was found to be sufficient to bring the OTA level to the maximum regulatory limit suggested for poultry feeds (100 µg kg(-1) ), while 8 h were needed to obtain this level using sunlight radiations. The proposed approach is a viable option to reduce the level of OTA in contaminated poultry feeds. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Prof. Masao Ota.

PubMed

Ono, Tomomichi

2017-01-01

Masao Ota was a Professor of Dermatology at Tokyo Imperial University. He is known to dermatologists around the world as the researcher who identified Nevus of Ota. He is also known for his research on Hansen's Disease. He was critical of the forced isolation policy and the sterilization law. He dreamt of developing chemotherapeutic measures and dedicated himself to cultivating Mycobacterium leprae. Among his accomplishments, those in the area of medical mycology are particularly remarkable. His discovery of Microsporum ferrugineum, his proposal for Trichophytia pompholyciformis, and his work on Ota-Langeron taxonomy based on the findings on fungus colonies are highly regarded and earned him the Ordre Royale de la Legion D'honneur. His accomplishments in the field of mycology are numerous; he has published a total of 39 research papers mostly in foreign languages. He was a leading world-class medical mycologist of his day. This review introduces some of his accomplishments and some episodes in his life.Furthermore, Masao Ota had a detailed knowledge of art and culture. Under the pseudonym of Kinoshita Mokutaro, he wrote poems, plays, and novels. He was also a painter. Particularly, his paintings in botany during his later years were published in the book "One Hundred Flower Sketches" after his death.Ota said, "The consequence of both science and art is global and humanitarian." He was one of the greatest men of culture in his time.

A fluorescent aptasensor based on a DNA pyramid nanostructure for ultrasensitive detection of ochratoxin A.

PubMed

Nameghi, Morteza Alinezhad; Danesh, Noor Mohammad; Ramezani, Mohammad; Hassani, Faezeh Vahdati; Abnous, Khalil; Taghdisi, Seyed Mohammad

2016-08-01

Analytical techniques for detection of ochratoxin A (OTA) in food products and blood serum are of great significance. In this study, a fluorescent aptasensor was developed for sensitive and specific detection of OTA, based on a DNA pyramid nanostructure (DPN) and PicoGreen (PG) dye. The designed aptasensor inherits characteristics of DPN, such as high stability and capacity for PG loading. PG, as a fluorescent dye, could bind to double-stranded DNA (dsDNA). In the absence of OTA, the pyramid structure of DPN remains intact, leading to a very strong fluorescence emission. Because of higher affinity of aptamer for its target relative to its complementary strand, upon addition of target, the pyramid structure of DPN is disassembled, leading to a weak fluorescence emission. The presented aptasensor showed high specificity toward OTA with a limit of detection (LOD) as low as 0.135 nM. Besides, the designed sensing strategy was successfully utilized to recognize OTA in serum and grape juice with LODs of 0.184 and 0.149 nM, respectively.

Mycobiota and concentration of ochratoxin A in concentrated poultry feed from Venezuela.

PubMed

Figueroa, S; Centeno, S; Calvo, M A; Rengel, A; Adelantado, C

2009-04-01

The main objective of this study was to evaluate the frequency distribution of mycobiota and the concentration of Ochratoxin A (OTA) in 50 samples from one company of commercial brand poultry feed produced in Venezuela. The concentration of OTA in the samples analyzed was determined using the competitive ELISA method. The most frequently isolated genera of moulds were Aspergillus (36%) and Penicillium (20%). Of these genera, the most frequently isolated species were Aspergillus flavus, Aspergillus terreus and Penicillium citrinum. Ochratoxigenic species such as Eurotium herbariorum, Aspergillus niger, Aspergillus ochraceus and Aspergillus glaucus, were also found with lower frequency. Rhodotorula mucilaginosa was the only yeast isolated. 94% of the samples presented contamination by OTA in a range between 2.558 and 31.978 microg kg(-1) feed and 42% of them presented OTA levels from 10 up to 20 microg kg(-1). The findings of this investigation show that 84% of the samples of concentrated feed for meat poultry surpass the maximum permitted limit for OTA of 5 microg kg(-1), established in the majority of countries in which regulations are placed.

The influence of salt (NaCl) on ochratoxin A biosynthetic genes, growth and ochratoxin A production by three strains of Penicillium nordicum on a dry-cured ham-based medium.

PubMed

Rodríguez, Alicia; Medina, Ángel; Córdoba, Juan J; Magan, Naresh

2014-05-16

Iberian dry-cured ham is colonised by moulds during the ripening process. The environmental conditions occurring during the process including the salt content predisposes the surface to colonisation by Penicillium species, including Penicillium nordicum which can contaminate the curing ham with ochratoxin A (OTA). The objective of this study was to examine the effect of NaCl (10% and 22%=0.94 and 0.87 water activity (aw)) on the activation of two genes involved in the biosynthetic pathway for OTA production, otapksPN and otanpsPN, relative growth and phenotypic OTA production by three strains of P. nordicum (CBS 110.769, FHSCC1 and FHSCC2) on a ham-based medium over a period of 12days at 25°C. Growth of the three strains was faster at 0.87 than 0.94 aw on the ham-based media. However, some intra- and inter-strain differences were observed. Of the three strains, only two (CBS 110.789; FHSCC2) were able to express the two genes involved in the biosynthesis of OTA in the two salt treatments. RT-qPCR showed that the temporal expression of the two genes (otapksPN and otanpsPN) was relatively similar for the wild type strain (FHSCC2) at both 0.94 and 0.87 aw over the 12day period. However, in the type strain (CBS 110.769) expression increased rapidly at 0.94 aw but was significantly lower at 0.87 aw. Expression of these two genes occurred after 3day incubation, while phenotypic OTA production was observed only after 6days in the two toxigenic strains. The other strain did not produce any OTA. The OTA concentrations confirmed the results observed with the molecular tools. This suggests that the RT-qPCR gene expression of these two genes may be a good early indicator of potential contamination of dry-cured ham with OTA during dry-cured ham ripening. Copyright © 2014 Elsevier B.V. All rights reserved.

Ochratoxin A and its metabolites in urines of German adults-An assessment of variables in biomarker analysis.

PubMed

Ali, Nurshad; Muñoz, Katherine; Degen, Gisela H

2017-06-05

Ochratoxin A (OTA), a mycotoxin known for its nephrotoxic and carcinogenic properties, is a worldwide occurring contaminant in a variety of food commodities. Biomonitoring (i.e. analysis in biological fluids) can serve to assess human internal exposure from all consumed foods and beverages. We now determined the concentration of OTA and its metabolite ochratoxin alpha (OTα) in plasma and in urine of two male volunteers with different food habits, in order to assess intra-individual temporal fluctuations and inter-individual differences in their biomarker levels. Moreover, the urinary levels of both OTA and OTα were analyzed in a cohort of German adults (23 males, 27 females) on their regular diet. All samples were subjected to an enzymatic hydrolysis of biomarker conjugates prior to clean-up by liquid-liquid extraction and HPLC-FD analysis. The profile in the first individual showed small fluctuations over time: mean levels in plasma were 0.42 and 0.45ng/mL for OTA and OTα, respectively, and in urine means of 0.06ng/mL for both analytes. The other individual had mean levels of 1.64 and 0.20ng/mL for OTA and OTα in plasma, and 0.24 and 2.22ng/mL for these analytes in urine. It is concluded that inter-individual differences in biomarker levels reflect dissimilar dietary exposure and/or disposition of ingested mycotoxin, with an apparently more efficient detoxification of OTA to OTα in the second individual. In the German cohort (n=50), analytes were detected in 100% (OTA: range 0.02-1.82ng/mL mean level 0.21±0.31ng/mL) and 78% (OTα: range 0.01-14.25ng/mL, mean level 1.33±2.63ng/mL) of all urines. Parameters such as gender, age and body mass index did not show a significant association with urine biomarker levels. This study indicates frequent exposure to OTA among German adults. The new results are discussed in the context of biomarker data from other countries and some methodological issues. Copyright © 2017 Elsevier B.V. All rights reserved.

T-2 Toxin/HT-2 Toxin and Ochratoxin A ELISAs Development and In-House Validation in Food in Accordance with Commission Regulation (EU) No 519/2014

PubMed Central

Oplatowska-Stachowiak, Michalina; Sajic, Nermin; Haasnoot, Willem; Campbell, Katrina; Elliott, Christopher T.; Salden, Martin

2017-01-01

T-2 toxin/HT-2 toxin (T-2/HT-2) and ochratoxin A (OTA) are mycotoxins that can contaminate a variety of agricultural commodities. To protect consumers’ health, indicative limits for T-2/HT-2 and maximum limits for OTA have been set by the European Commission, requiring food business operators and controlling agencies to conduct routine checks for the presence of these harmful contaminants. Screening methods are increasingly used for monitoring purposes. Due to the demand for new and improved screening tools, two individual detection methods, T-2/HT-2 and OTA enzyme-linked immunosorbent assays (ELISAs), were developed in this study. The T-2/HT-2 ELISA was based on a T-2 monoclonal antibody with an IC50 (50% inhibitory concentration) of 0.28 ng/mL and 125% cross-reactivity with HT-2. As regards the OTA ELISA, a new sensitive monoclonal antibody specific to OTA with an IC50 of 0.13 ng/mL was produced. Both developed ELISA tests were then validated in agricultural commodities in accordance with the new performance criteria guidelines for the validation of screening methods for mycotoxins included in Commission Regulation (EU) No 519/2014. The T-2/HT-2 ELISA was demonstrated to be suitable for the detection of T-2/HT-2 in cereals and baby food at and above the screening target concentration (STC) of 12.5 μg/kg and 7.5 μg/kg, respectively. The OTA ELISA was shown to be applicable for the detection of OTA in cereals, coffee, cocoa and wine at and above the STC of 2 μg/kg, 2.5 μg/kg, 2.5 μg/kg and 0.4 ng/mL, respectively. The accuracy of both ELISAs was further confirmed by analysing proficiency test and reference samples. The developed methods can be used for sensitive and high-throughput screening for the presence of T-2/HT-2 and OTA in agricultural commodities. PMID:29189752

T-2 Toxin/HT-2 Toxin and Ochratoxin A ELISAs Development and In-House Validation in Food in Accordance with the Commission Regulation (EU) No 519/2014.

PubMed

Oplatowska-Stachowiak, Michalina; Kleintjens, Tim; Sajic, Nermin; Haasnoot, Willem; Campbell, Katrina; Elliott, Christopher T; Salden, Martin

2017-11-30

T-2 toxin/HT-2 toxin (T-2/HT-2) and ochratoxin A (OTA) are mycotoxins that can contaminate a variety of agricultural commodities. To protect consumers' health, indicative limits for T-2/HT-2 and maximum limits for OTA have been set by the European Commission, requiring food business operators and controlling agencies to conduct routine checks for the presence of these harmful contaminants. Screening methods are increasingly used for monitoring purposes. Due to the demand for new and improved screening tools, two individual detection methods, T-2/HT-2 and OTA enzyme-linked immunosorbent assays (ELISAs), were developed in this study. The T-2/HT-2 ELISA was based on a T-2 monoclonal antibody with an IC 50 (50% inhibitory concentration) of 0.28 ng/mL and 125% cross-reactivity with HT-2. As regards the OTA ELISA, a new sensitive monoclonal antibody specific to OTA with an IC 50 of 0.13 ng/mL was produced. Both developed ELISA tests were then validated in agricultural commodities in accordance with the new performance criteria guidelines for the validation of screening methods for mycotoxins included in Commission Regulation (EU) No 519/2014. The T-2/HT-2 ELISA was demonstrated to be suitable for the detection of T-2/HT-2 in cereals and baby food at and above the screening target concentration (STC) of 12.5 μg/kg and 7.5 μg/kg, respectively. The OTA ELISA was shown to be applicable for the detection of OTA in cereals, coffee, cocoa and wine at and above the STC of 2 μg/kg, 2.5 μg/kg, 2.5 μg/kg and 0.4 ng/mL, respectively. The accuracy of both ELISAs was further confirmed by analysing proficiency test and reference samples. The developed methods can be used for sensitive and high-throughput screening for the presence of T-2/HT-2 and OTA in agricultural commodities.

Nonproliferation vs. Industrial Competitiveness: U.S. Export Controls and the Dual-Use Machine Tool Industry

DTIC Science & Technology

1995-06-01

Economic Foundations of the Next Security System, Berkeley Roundtable on the International Economy (BRIE), (Oxford: Oxford University Press , 1992), pp...former Eastern bloc." 9Michael Mastanduno, Economic Containment: COCOM and the Politics of East-West Trade. (Ithaca: Cornell University Press , 1992...Environment (Washington, DC: National Academy Press , 1991), pp. 61-105. ŕOTA, 1994, p. 49. 6 The United States participates in several multilateral regimes

Ochratoxin A at nanomolar concentration perturbs the homeostasis of neural stem cells in highly differentiated but not in immature three-dimensional brain cell cultures.

PubMed

Zurich, Marie-Gabrielle; Honegger, Paul

2011-08-28

Ochratoxin A (OTA), a fungal contaminant of basic food commodities, is known to be highly cytotoxic, but the pathways underlying adverse effects at subcytotoxic concentrations remain to be elucidated. Recent reports indicate that OTA affects cell cycle regulation. Therefore, 3D brain cell cultures were used to study OTA effects on mitotically active neural stem/progenitor cells, comparing highly differentiated cultures with their immature counterparts. Changes in the rate of DNA synthesis were related to early changes in the mRNA expression of neural stem/progenitor cell markers. OTA at 10nM, a concentration below the cytotoxic level, was ineffective in immature cultures, whereas in mature cultures it significantly decreased the rate of DNA synthesis together with the mRNA expression of key transcriptional regulators such as Sox2, Mash1, Hes5, and Gli1; the cell cycle activator cyclin D2; the phenotypic markers nestin, doublecortin, and PDGFRα. These effects were largely prevented by Sonic hedgehog (Shh) peptide (500ngml(-1)) administration, indicating that OTA impaired the Shh pathway and the Sox2 regulatory transcription factor critical for stem cell self-renewal. Similar adverse effects of OTA in vivo might perturb the regulation of stem cell proliferation in the adult brain and in other organs exhibiting homeostatic and/or regenerative cell proliferation. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Description of an orthologous cluster of ochratoxin A biosynthetic genes in Aspergillus and Penicillium species. A comparative analysis.

PubMed

Gil-Serna, Jessica; García-Díaz, Marta; González-Jaén, María Teresa; Vázquez, Covadonga; Patiño, Belén

2018-03-02

Ochratoxin A (OTA) is one of the most important mycotoxins due to its toxic properties and worldwide distribution which is produced by several Aspergillus and Penicillium species. The knowledge of OTA biosynthetic genes and understanding of the mechanisms involved in their regulation are essential. In this work, we obtained a clear picture of biosynthetic genes organization in the main OTA-producing Aspergillus and Penicillium species (A. steynii, A. westerdijkiae, A. niger, A. carbonarius and P. nordicum) using complete genome sequences obtained in this work or previously available on databases. The results revealed a region containing five ORFs which predicted five proteins: halogenase, bZIP transcription factor, cytochrome P450 monooxygenase, non-ribosomal peptide synthetase and polyketide synthase in all the five species. Genetic synteny was conserved in both Penicillium and Aspergillus species although genomic location seemed to be different since the clusters presented different flanking regions (except for A. steynii and A. westerdijkiae); these observations support the hypothesis of the orthology of this genomic region and that it might have been acquired by horizontal transfer. New real-time RT-PCR assays for quantification of the expression of these OTA biosynthetic genes were developed. In all species, the five genes were consistently expressed in OTA-producing strains in permissive conditions. These protocols might favour futures studies on the regulation of biosynthetic genes in order to develop new efficient control methods to avoid OTA entering the food chain. Copyright © 2018 Elsevier B.V. All rights reserved.

Ochratoxin A in cocoa and chocolate sampled in Canada.

PubMed

Turcotte, A-M; Scott, P M

2011-06-01

In order to determine the levels of ochratoxin A (OTA) in cocoa and cocoa products available in Canada, a previously published analytical method, with minor modifications to the extraction and immunoaffinity clean-up and inclusion of an evaporation step, was initially used (Method I). To improve the low method recoveries (46-61%), 40% methanol was then included in the aqueous sodium bicarbonate extraction solvent (pH 7.8) (Method II). Clean-up was on an Ochratest™ immunoaffinity column and OTA was determined by liquid chromatography (LC) with fluorescence detection. Recoveries of OTA from spiked cocoa powder (0.5 and 5 ng g(-1)) were 75-84%; while recoveries from chocolate were 93-94%. The optimized method was sensitive (limit of quantification (LOQ) = 0.07-0.08 ng g(-1)), accurate (recovery = 75-94%) and precise (coefficient of variation (CV) < 5%). It is applicable to cocoa and chocolate. Analysis of 32 samples of cocoa powder (16 alkalized and 16 natural) for OTA showed an incidence of 100%, with concentrations ranging from 0.25 to 7.8 ng g(-1); in six samples the OTA level exceeded 2 ng g(-1), the previously considered European Union limit for cocoa. The frequency of detection of OTA in 28 chocolate samples (21 dark or baking chocolate and seven milk chocolate) was also 100% with concentrations ranging from 0.05 to 1.4 ng g(-1); one sample had a level higher than the previously considered European Union limit for chocolate (1 ng g(-1)).

Evaluation of extraction methods for ochratoxin A detection in cocoa beans employing HPLC.

PubMed

Mishra, Rupesh K; Catanante, Gaëlle; Hayat, Akhtar; Marty, Jean-Louis

2016-01-01

Cocoa is an important ingredient for the chocolate industry and for many food products. However, it is prone to contamination by ochratoxin A (OTA), which is highly toxic and potentially carcinogenic to humans. In this work, four different extraction methods were tested and compared based on their recoveries. The best protocol was established which involves an organic solvent-free extraction method for the detection of OTA in cocoa beans using 1% sodium hydrogen carbonate (NaHCO3) in water within 30 min. The extraction method is rapid (as compared with existing methods), simple, reliable and practical to perform without complex experimental set-ups. The cocoa samples were freshly extracted and cleaned-up using immunoaffinity column (IAC) for HPLC analysis using a fluorescence detector. Under the optimised condition, the limit of detection (LOD) and limit of quantification (LOQ) for OTA were 0.62 and 1.25 ng ml(-1) respectively in standard solutions. The method could successfully quantify OTA in naturally contaminated samples. Moreover, good recoveries of OTA were obtained up to 86.5% in artificially spiked cocoa samples, with a maximum relative standard deviation (RSD) of 2.7%. The proposed extraction method could determine OTA at the level 1.5 µg kg(-)(1), which surpassed the standards set by the European Union for cocoa (2 µg kg(-1)). In addition, an efficiency comparison of IAC and molecular imprinted polymer (MIP) column was also performed and evaluated.

The food contaminant and nephrotoxin ochratoxin A enhances Wnt1 inducible signaling protein 1 and tumor necrosis factor-α expression in human primary proximal tubule cells.

PubMed

Hennemeier, Isabell; Humpf, Hans-Ulrich; Gekle, Michael; Schwerdt, Gerald

2012-09-01

The underlying molecular mechanisms of nanomolar ochratoxin A (OTA) concentrations, especially those on pathophysiological relevant gene expression in target tissue and underlying signaling mechanisms are unknown. qPCR arrays showed that 14 days exposure of human primary proximal tubule cells to 10 nM OTA influences the expression of genes that are related to inflammation, malignant transformation, and epithelial-to-mesenchymal transition. Wnt1 inducible signaling protein 1 (WISP1), an oncogenic, and profibrotic growth factor, turned out to be the gene with the strongest upregulation. Its expression, and that of TNF-α, an important inflammatory mediator, was further investigated in human renal cells and in primary human lung fibroblasts. OTA-induced upregulation of WISP1 and TNF-α occurs only in renal cells. Inhibition of ERK1/2 activation reverses the effect of OTA on WISP1 and TNF-α expression. Wnt or other signaling pathways were not involved. Upregulation of WISP1 and TNF-α occured independently of each other. Long-term exposure of human kidney cells with OTA concentrations expectable in renal tissue due to average dietary intake leads in an ERK1/2-dependent manner to pathogenetic alterations of gene expression, notably WISP1 and TNF-α. Renal long-term risk by OTA is actually not excludable and argues for low but rational safety levels. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Blocking oxytocin receptors inhibits vaginal marking to male odors in female Syrian hamsters.

PubMed

Martinez, Luis A; Albers, H Elliott; Petrulis, Aras

2010-12-02

In Syrian hamsters (Mesocricetus auratus), precopulatory behaviors such as vaginal scent marking are essential for attracting a suitable mate. Vaginal marking is dependent on forebrain areas implicated in the neural regulation of reproductive behaviors in rodents, including the medial preoptic/anterior hypothalamus (MPOA-AH). Within MPOA-AH, the neuropeptide oxytocin (OT) acts to facilitate copulation (lordosis), as well as ultrasonic vocalizations towards males. It is not known, however, if OT in this area also facilitates vaginal marking. In the present study, a specific oxytocin receptor antagonist (OTA) was injected into MPOA-AH of intact female Syrian hamsters to determine if oxytocin receptor-dependent signaling is critical for the normal expression of vaginal marking elicited by male, female, and clean odors. OTA injections significantly inhibited vaginal marking in response to male odors compared with vehicle injections. There was no effect of OTA on marking in response to either female or clean odors. When injected into the bed nucleus of the stria terminalis (BNST), a nearby region to MPOA-AH, OTA was equally effective in decreasing marking. Finally, the effects of OTA appear to be specific to vaginal marking, as OTA injections in MPOA-AH or BNST did not alter general locomotor activity, flank marking, or social odor investigation. Considered together, these results suggest that OT in MPOA-AH and/or BNST normally facilitates male odor-induced vaginal marking, providing further evidence that OT generally supports prosocial interactions among conspecifics. Copyright © 2010 Elsevier Inc. All rights reserved.

Determination of ochratoxin A in traditional Chinese medicinal plants by HPLC-FLD.

PubMed

Yang, Lei; Wang, Linan; Pan, Jianyu; Xiang, Lan; Yang, Meihua; Logrieco, Antonio F

2010-07-01

Traditional Chinese medicinal plants (TCMPs), commonly used as spices, additives or foods, are also widely used in China to prevent and cure human disease. Due to their provenance, TCMPs may be contaminated by various fungal species, including ochratoxigenic fungi, during growth, collection, transportation and, especially, storage. A reliable method for the determination of ochratoxin A (OTA) in TCMPs of different origins was developed to monitor OTA levels in China. Analyses involved the extraction of OTA by methanol/water, immunoaffinity column (IAC) clean-up and HPLC quantification with fluorescence detection (FLD). Positive results were further confirmed by LC-ESI-MS/MS. The limit of detection (LOD) was 0.3 microg kg(-1), based on a signal-to-noise ratio of 3 : 1. Among the total of 57 TCMPs samples collected from six different areas, 31 were visibly moldy due to inappropriate storage; 26 sample, purchased from local TCMPs markets, were not visibly moldy. The results showed that 23 of the visibly moldy samples and two of the not visibly moldy were contaminated with OTA at levels ranging 1.2-158.7 and 2.5-5.6 microg kg(-1), respectively. This is the first report of the natural occurrence of OTA in TCMPs.

Gasohol : A Technical Memorandum

DOT National Transportation Integrated Search

1979-09-01

The Office of Technology Assessment (OTA) is preparing an assessment of energy from biological processes. In the course of this study OTA has carried out an extensive analysis of alcohol fuels from agricultural products. The purpose of this memorandu...

Ochratoxin A Contamination of Red Chili Peppers from Chile, Bolivia and Peru, Countries with a High Incidence of Gallbladder Cancer.

PubMed

Ikoma, Toshikazu; Tsuchiya, Yasuo; Asai, Takao; Okano, Kiyoshi; Ito, Naoko; Endoh, Kazuo; Yamamoto, Masaharu; Nakamura, Kazutoshi

2015-01-01

Our previous study detected aflatoxins in red chili peppers from Chile, Bolivia, and Peru, each of which have a high incidence of gallbladder cancer (GBC). Since the aflatoxin B1 concentration was not so high in these peppers, it is important to clarify the presence of other mycotoxins. Here we attempted to determine any associations between the concentrations of aflatoxins and ochratoxin A (OTA) in red chili peppers, and the corresponding GBC incidences. We collected red chili peppers from three areas in Peru: Trujillo (a high GBC incidence area), Cusco (an intermediate GBC incidence area), and Lima (a low GBC incidence rate), and from Chile and Bolivia. Aflatoxins and OTA were extracted with organic solvents. The concentrations of aflatoxins B1, B2, G1, and G2, and OTA were measured by high-performance liquid chromatography. The values obtained were compared with the incidence of GBC in each area or country. All of the red chili peppers from the three areas showed contamination with aflatoxins below the Commission of the European Communities (EC) recommended limits (5 μg/kg), but the OTA contamination of two samples was above the EC recommended limit (15 μg/kg). The mean concentrations of OTA in the peppers from Chile (mean 355 μg/kg, range <5-1,059 μg/kg) and Bolivia (mean 207 μg/kg, range 0.8-628 μg/kg), which has a high incidence of GBC, were higher than that in Peru (14 μg/kg, range <5-47 μg/kg), which has an intermediate GBC incidence. The OTA contamination in the red chili peppers from Chile, Bolivia, and Peru was stronger than that of aflatoxins. Our data suggest that OTA in red chili peppers may be associated with the development of GBC.

Effect of temperature, water activity, and pH on growth and production of ochratoxin A by Aspergillus niger and Aspergillus carbonarius from Brazilian grapes.

PubMed

Passamani, Fabiana Reinis Franca; Hernandes, Thais; Lopes, Noelly Alves; Bastos, Sabrina Carvalho; Santiago, Wilder Douglas; Cardoso, Maria das Graças; Batista, Luís Roberto

2014-11-01

The growth of ochratoxigenic fungus and the presence of ochratoxin A (OTA) in grapes and their derivatives can be caused by a wide range of physical, chemical, and biological factors. The determination of interactions between these factors and fungal species from different climatic regions is important in designing models for minimizing the risk of OTA in wine and grape juice. This study evaluated the influence of temperature, water activity (aw), and pH on the development and production of OTA in a semisynthetic grape culture medium by Aspergillus carbonarius and Aspergillus niger strains. To analyze the growth conditions and production of OTA, an experimental design was conducted using response surface methodology as a tool to assess the effects of these abiotic variables on fungal behavior. A. carbonarius showed the highest growth at temperatures from 20 to 33°C, aw between 0.95 and 0.98, and pH levels between 5 and 6.5. Similarly, for A. niger, temperatures between 24 and 37°C, aw greater than 0.95, and pH levels between 4 and 6.5 were optimal. The greatest toxin concentrations for A. carbonarius and A. niger (10 μg/g and 7.0 μg/g, respectively) were found at 15°C, aw 0.99, and pH 5.35. The lowest pH was found to contribute to greater OTA production. These results show that the evaluated fungi are able to grow and produce OTA in a wide range of temperature, aw, and pH. However, the optimal conditions for toxin production are generally different from those optimal for fungal growth. The knowledge of optimal conditions for fungal growth and production of OTA, and of the stages of cultivation in which these conditions are optimal, allows a more precise assessment of the potential risk to health from consumption of products derived from grapes.

Analysis of cocoa products for ochratoxin A and aflatoxins.

PubMed

Turcotte, Anne-Marie; Scott, Peter M; Tague, Brett

2013-08-01

Eighty-five samples of cocoa products sampled in Canada were analysed for ochratoxin A (OTA) and aflatoxins in 2011-2012. Inclusion of the aflatoxins in this survey required additional method development. Chocolate was extracted with methanol-water plus NaCl, while for cocoa two successive extractions with methanol and methanol-water were made. Extracts were cleaned on an AflaOchra immunoaffinity column (IAC). Determination was by reversed phase high performance liquid chromatography (HPLC). Detection of the aflatoxins was with a post-column photochemical reactor and of OTA by fluorescence detection. Mean limits of quantification (LOQ) of chocolate and cocoa powders were 0.16 ng/g (OTA) and 0.07 ng/g (aflatoxin B1), respectively. Survey results showed that the incidences of OTA above the LOQ in natural cocoa were 15/15 (mean 1.17 ng/g), 20/21 for alkalized cocoa (mean 1.06 ng/g), 9/9 for baking chocolate (mean 0.49 ng/g), 20/20 for dark chocolate (mean 0.39 ng/g), 7/10 for milk chocolate (mean 0.19 ng/g), 5/5 for cocoa liquor (mean 0.43 ng/g), and 0/5 for cocoa butter. These results confirm our previous work with OTA. In the same samples, incidences of aflatoxin B1 above the LOQ were 14/15 for natural cocoa (mean 0.86 ng/g), 20/21 for alkalized cocoa (mean 0.37 ng/g), 7/9 for baking chocolate (mean 0.22 ng/g), 16/20 for dark chocolate (mean 0.19 ng/g), 7/10 for milk chocolate (mean 0.09 ng/g), 4/5 for cocoa liquor (mean 0.43 ng/g), and 0/5 for cocoa butter. Both aflatoxins and OTA were confirmed by HPLC-MS/MS when OTA or aflatoxin levels found were above 2 ng/g in cocoa.

Method validation for the determination of ochratoxin A in green and soluble coffee by immunoaffinity column cleanup and liquid chromatography.

PubMed

Diaz, G J; Ariza, D; Perilla, N S

2004-06-01

A method was validated for the determination of ochratoxin A (OTA) in soluble and green coffee. Performance parameters evaluated included selectivity, accuracy, intermediate precision, linearity, limit of detection, limit of quantitation, and ruggedness. The method was found to be selective for OTA in both matrices tested. Recovery rates from soluble coffee samples ranged from 73.5 to 91.2%, and from green coffee samples from 68.7 to 84.5%. The intermediate precision (RSDr) was between 9.1 and 9.4% for soluble coffee and between 14.3 and 15.5% for green coffee analysis. The linearity of the standard calibration curve (r(2)) was <0.999 for OTA levels of 1.0-20.0 μg/kg in coffee samples. The limit of detection was determined to be 0.01 ng of OTA on column, while the limit of quantitation was found to be 0.03 ng on column. The limit of quantitation is equivalent to 0.6 μg/kg in soluble coffee samples and 0.3 μg/kg in green coffee samples. The results of the ruggedness trial showed two factors are critical for soluble coffee analysis: the extraction method, and the flow rate of the mobile phase. For green coffee analysis two critical factors detected were the extraction method and the storage temperature of the immunoaffinity column.Five samples of soluble coffee and 42 of green coffee were analysed using the validated method. All soluble coffee samples contained OTA at levels that ranged from 8.4 to 13.9 μg/kg. Six of the 42 green coffee samples analysed (14.3%) contained OTA at levels ranging from 0.9 to 19.4 μg/kg. The validated method can be used to monitor OTA levels in Colombian coffee for export or for local consumption.

Two New Fluorogenic Aptasensors Based on Capped Mesoporous Silica Nanoparticles to Detect Ochratoxin A

PubMed Central

Ribes, Àngela; Santiago‐Felipe, Sara; Bernardos, Andrea; Marcos, M. Dolores; Pardo, Teresa; Sancenón, Félix; Aznar, Elena

2017-01-01

Abstract Aptamers have been used as recognition elements for several molecules due to their great affinity and selectivity. Additionally, mesoporous nanomaterials have demonstrated great potential in sensing applications. Based on these concepts, we report herein the use of two aptamer‐capped mesoporous silica materials for the selective detection of ochratoxin A (OTA). A specific aptamer for OTA was used to block the pores of rhodamine B‐loaded mesoporous silica nanoparticles. Two solids were prepared in which the aptamer capped the porous scaffolds by using a covalent or electrostatic approach. Whereas the prepared materials remained capped in water, dye delivery was selectively observed in the presence of OTA. The protocol showed excellent analytical performance in terms of sensitivity (limit of detection: 0.5–0.05 nm), reproducibility, and selectivity. Moreover, the aptasensors were tested for OTA detection in commercial foodstuff matrices, which demonstrated their potential applicability in real samples. PMID:29046860

Ochratoxin A levels in spices and dried nuts consumed in Tunisia.

PubMed

Zaied, Chiraz; Abid, Salwa; Bouaziz, Chayma; Chouchane, Salwa; Jomaa, Mohamed; Bacha, Hassen

2010-01-01

A total of 112 samples of spices (24 caraway, 20 coriander, 25 curcuma, 20 black pepper and 23 red pepper) and 110 samples of dried nuts (44 almonds, 42 peanuts and 24 pistachio) purchased from popular markets in 24 regions of Tunisia were analyzed for ochratoxin A (OTA) by fluorescence HPLC. The average levels of contamination of OTA found in spice samples were 244, 206, 290, 274 and 203 µg/kg, respectively, for caraway, coriander, curcuma, black pepper and red pepper. Concerning dried nut samples, the average levels were 61, 60 and 89 µg/kg, respectively, for almonds, peanuts and pistachio. Contamination levels were higher than the usual norms (10.0 OTA µg/kg) established by the European Commission in 2005 . This survey is the first to be carried out on the natural occurrence of OTA in the main spices and dried nuts consumed by the Tunisian population.

A study on the clinical characteristics of treating nevus of Ota by Q-switched Nd:YAG laser.

PubMed

Yan, Liu; Di, Li; Weihua, Wang; Feng, Liu; Ruilian, Li; Jun, Zhou; Hui, Su; Zhaoxia, Ying; Weihui, Zeng

2018-01-01

The purpose of this study was to retrospectively analyze the clinical characteristics of treating nevus of Ota by Q-switched Nd:YAG laser in Laser Cosmetology Center of Department of Dermatology, the Second Hospital, Xi'an Jiaotong University. The data of 1168 patients of nevus of Ota were analyzed retrospectively, which included the correlation among lesion color, treatment sessions, sex, age, lesion types, and effect. The Q-switched (QS) Nd:YAG laser system had a higher number of treatment sessions which were positively associated with a better response to treatment. Other variables, including gender, age, the categorization of the lesion according to Tanino's classification, and the color of the lesion, were not associated with the response to treatment. The treatment of nevus of Ota with QS Nd:YAG laser is safe and effective, with rare complications.

An optical fiber-based LSPR aptasensor for simple and rapid in-situ detection of ochratoxin A.

PubMed

Lee, Bobin; Park, Jin-Ho; Byun, Ju-Young; Kim, Joon Heon; Kim, Min-Gon

2018-04-15

Label-free biosensing methods that rely on the use of localized surface plasmon resonance (LSPR) have attracted great attention as a result of their simplicity, high sensitivity, and relatively low cost. However, in-situ analysis of real samples using these techniques has remained challenging because colloidal nanoparticles (NPs) can be unstable at certain levels of pH and salt concentration. Even in the case of a chip-type LSPR sensor that can resolve the instability problem by employing NPs immobilized on the substrate, loading of a sample to sensor chip with exact volume control can be difficult for unskilled users. Herein, we report an optical-fiber-based LSPR aptasensor that can avoid these problems and serve as a portable and simple system for sensitive detection of a small mycotoxin, ochratoxin A (OTA), in real samples. The optical fiber coated with aptamer-modified gold nanorods (GNRs) is simply dipped into a solution containing OTA and subjected to LSPR analysis. Quantitative analysis of OTA is performed by measuring the spectral red shift of the LSPR peak of GNRs. Under optimized conditions, the LSPR peak shift displays a linear response (R 2 = 0.9887) to OTA in the concentration range from 10pM to 100nM, with a limit of detection of 12.0pM (3S). The developed sensor shows a high selectivity for OTA over other mycotoxins such as zearalenone (ZEN) and ochratoxin B (OTB), and shows an accurate detection capability for OTA in real grape juice samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of the Content and Accessibility of Web Sites for Accredited Orthopaedic Trauma Surgery Fellowships.

PubMed

Shaath, M Kareem; Yeranosian, Michael G; Ippolito, Joseph A; Adams, Mark R; Sirkin, Michael S; Reilly, Mark C

2018-05-02

Orthopaedic trauma fellowship applicants use online-based resources when researching information on potential U.S. fellowship programs. The 2 primary sources for identifying programs are the Orthopaedic Trauma Association (OTA) database and the San Francisco Match (SF Match) database. Previous studies in other orthopaedic subspecialty areas have demonstrated considerable discrepancies among fellowship programs. The purpose of this study was to analyze content and availability of information on orthopaedic trauma surgery fellowship web sites. The online databases of the OTA and SF Match were reviewed to determine the availability of embedded program links or external links for the included programs. Thereafter, a Google search was performed for each program individually by typing the program's name, followed by the term "orthopaedic trauma fellowship." All identified fellowship web sites were analyzed for accessibility and content. Web sites were evaluated for comprehensiveness in mentioning key components of the orthopaedic trauma surgery curriculum. By consensus, we refined the final list of variables utilizing the methodology of previous studies on the topic. We identified 54 OTA-accredited fellowship programs, offering 87 positions. The majority (94%) of programs had web sites accessible through a Google search. Of the 51 web sites found, all (100%) described their program. Most commonly, hospital affiliation (88%), operative experiences (76%), and rotation overview (65%) were listed, and, least commonly, interview dates (6%), selection criteria (16%), on-call requirements (20%), and fellow evaluation criteria (20%) were listed. Programs with ≥2 fellows provided more information with regard to education content (p = 0.0001) and recruitment content (p = 0.013). Programs with Accreditation Council for Graduate Medical Education (ACGME) accreditation status also provided greater information with regard to education content (odds ratio, 4.0; p = 0.0001). Otherwise, no differences were seen by region, residency affiliation, medical school affiliation, or hospital affiliation. The SF Match and OTA databases provide few direct links to fellowship web sites. Individual program web sites do not effectively and completely convey information about the programs. The Internet is an underused resource for fellow recruitment. The lack of information on these sites allows for future opportunity to optimize this resource.

Changing by degrees : steps to reduce greenhouse gases

DOT National Transportation Integrated Search

1991-02-01

The six congressional committees requesting this assessment asked OTA to focus on a very specific question: "Can the United States reduce carbon dioxide emissions in the near term?" To answer the question Congress posed, OTA focuses specifically on p...

The brownfields program: Reclaiming inner-city sites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, B.

Over the past 25 years, enormous environmental resources have been directed through the Comprehensive Environmental Response Compensation and Liability Act (CERCLA), or Superfund, at cleaning up past environmental abuses, while the Resource Conservation and Recovery Act (RCRA) has been the principal federal statute to prevent future abuses to public health and the environment. Only recently, however, has attention turned to a third general area of concern, the redevelopment of abandoned or underutilized land and buildings in many central cities and inner suburbs of US metropolitan areas. In June of this year, the Office of Technology Assessment (OTA) released a reportmore » called State of the State on Brownfields: Program for Clean-up and Reuse of Contaminated Sites (OTA Report), in which it was estimated that the size of the problem varies from tens of thousands to nearly 450,000 sites. Many brownfield sites are located in the Northeast and Midwest where, historically, much of the economy was based on heavy industrial activity, although in actuality these brownfields are scattered throughout the entire country.« less

Ochratoxin A in Portugal: A Review to Assess Human Exposure

PubMed Central

Duarte, Sofia C.; Pena, Angelina; Lino, Celeste M.

2010-01-01

In Portugal, the climate, dietary habits, and food contamination levels present the characteristics for higher population susceptibility to ochratoxin A (OTA), one of the known mycotoxins with the greatest public health and agro-economic importance. In this review, following a brief historical insight on OTA research, a summary of the available data on OTA occurrence in food (cereals, bread, wine, meat) and biological fluids (blood, urine) is made. With this data, an estimation of intake is made to ascertain and update the risk exposure estimation of the Portuguese population, in comparison to previous studies and other populations. PMID:22069635

A Review of the Diagnosis and Treatment of Ochratoxin A Inhalational Exposure Associated with Human Illness and Kidney Disease including Focal Segmental Glomerulosclerosis

PubMed Central

Hope, Janette H.; Hope, Bradley E.

2012-01-01

Ochratoxin A (OTA) exposure via ingestion and inhalation has been described in the literature to cause kidney disease in both animals and humans. This paper reviews Ochratoxin A and its relationship to human health and kidney disease with a focus on a possible association with focal segmental glomerulosclerosis (FSGS) in humans. Prevention and treatment strategies for OTA-induced illness are also discussed, including cholestyramine, a bile-acid-binding resin used as a sequestrant to reduce the enterohepatic recirculation of OTA. PMID:22253638

Titanium Dioxide Nanoparticles (TiO₂) Quenching Based Aptasensing Platform: Application to Ochratoxin A Detection.

PubMed

Sharma, Atul; Hayat, Akhtar; Mishra, Rupesh K; Catanante, Gaëlle; Bhand, Sunil; Marty, Jean Louis

2015-09-22

We demonstrate for the first time, the development of titanium dioxide nanoparticles (TiO₂) quenching based aptasensing platform for detection of target molecules. TiO₂ quench the fluorescence of FAM-labeled aptamer (fluorescein labeled aptamer) upon the non-covalent adsorption of fluorescent labeled aptamer on TiO₂ surface. When OTA interacts with the aptamer, it induced aptamer G-quadruplex complex formation, weakens the interaction between FAM-labeled aptamer and TiO₂, resulting in fluorescence recovery. As a proof of concept, an assay was employed for detection of Ochratoxin A (OTA). At optimized experimental condition, the obtained limit of detection (LOD) was 1.5 nM with a good linearity in the range 1.5 nM to 1.0 µM for OTA. The obtained results showed the high selectivity of assay towards OTA without interference to structurally similar analogue Ochratoxin B (OTB). The developed aptamer assay was evaluated for detection of OTA in beer sample and recoveries were recorded in the range from 94.30%-99.20%. Analytical figures of the merits of the developed aptasensing platform confirmed its applicability to real samples analysis. However, this is a generic aptasensing platform and can be extended for detection of other toxins or target analyte.

A novel fluorescent aptasensor based on gold and silica nanoparticles for the ultrasensitive detection of ochratoxin A

NASA Astrophysics Data System (ADS)

Taghdisi, Seyed Mohammad; Danesh, Noor Mohammad; Beheshti, Hamed Reza; Ramezani, Mohammad; Abnous, Khalil

2016-02-01

Analytical approaches for the detection and quantitation of ochratoxin A (OTA) in blood serum and food products are high in demand. In this study, a fluorescent aptamer-based sensor (aptasensor) is developed for the selective and sensitive detection of OTA, based on a complementary strand of aptamer (CS) and two types of nanoparticles, gold nanoparticles (AuNPs) and silica nanoparticles (SNPs) coated with streptavidin. The fabricated aptasensor inherits the characteristics of SNPs, as enhancers of fluorescence intensity; AuNPs, such as large surface area and unique optical properties; and high affinity of the aptamer toward its target compared to its CS. In the absence of OTA, no FAM and biotin-labeled CS is in the environment of the SNPs coated with streptavidin, which leads to no fluorescence emission. In the presence of the target, an FAM and biotin-labeled CS-SNPs coated with streptavidin conjugate is formed, thus resulting in a very strong fluorescence emission. The designed fluorescent aptasensor exhibits high selectivity toward OTA with a limit of detection (LOD) as low as 0.098 nM. Furthermore, the fabricated aptasensor was successfully applied for the detection of OTA in grape juice and serum with LODs of 0.113 and 0.152 nM, respectively.

A label free aptasensor for Ochratoxin A detection in cocoa beans: An application to chocolate industries.

PubMed

Mishra, Rupesh K; Hayat, Akhtar; Catanante, Gaëlle; Ocaña, Cristina; Marty, Jean-Louis

2015-08-19

Contamination of food by mycotoxin occurs in minute/trace quantities. Nearly 92.5% of the cocoa samples present Ochratoxin A (OTA) levels at trace quantity. Hence, there is a necessity for a highly sensitive and selective device that can detect and quantify these organic toxins in various matrices such as cocoa beans. This work reports for the first time, a facile and label-free electrochemical impedimetric aptasensor for rapid detection and quantitation of OTA in cocoa beans. The developed aptasensor was constructed based on the diazonium-coupling reaction mechanism for the immobilization of anti-OTA-aptamer on screen printed carbon electrodes (SPCEs). The aptasensor exhibited a very good limit of detection (LOD) as low as 0.15 ng/mL, with added advantages of good selectivity and reproducibility. The increase in electron transfer resistance was linearly proportional to the OTA concentration in the range 0.15-2.5 ng/mL, with an acceptable recovery percentage (91-95%, RSD = 4.8%) obtained in cocoa samples. This work can facilitate a general model for the detection of OTA in cocoa beans based on the impedimetric aptasensor. The analysis can be performed onsite with pre-constructed and aptamer modified electrodes employing a portable EIS set up. Copyright © 2015 Elsevier B.V. All rights reserved.

Identification of ochratoxin A producing Aspergillus carbonarius and A. niger clade isolated from grapes using the loop-mediated isothermal amplification (LAMP) reaction.

PubMed

Storari, M; von Rohr, R; Pertot, I; Gessler, C; Broggini, G A L

2013-04-01

To develop two assays based on the loop-mediated isothermal amplification (LAMP) of DNA for the quick and specific identification of Aspergillus carbonarius and ochratoxigenic strains of the Aspergillus niger clade isolated from grapes. Two sets of primers were designed based on the polyketide synthase genes involved or putatively involved in ochratoxin A (OTA) biosynthesis in A. carbonarius and A. niger clade. Hydroxynaphthol blue was used as indirect method to indicate DNA amplification. The limit of detection of both assays was comparable to that of a PCR reaction. Specificities of the reactions were tested using DNA from different black aspergilli isolated from grapes. The two LAMP assays were then used to identify A. carbonarius and ochratoxigenic A. niger and A. awamori grown in pure cultures without a prior DNA extraction. The two LAMP assays permitted to quickly and specifically identify DNA from OTA-producing black aspergilli, as well as isolates grown in pure culture. Monitoring vineyards for the presence of OTA-producing strains is part of the measures to minimize the occurrence of OTA in grape products. The two LAMP assays developed here could be potentially used to speed the screening process of vineyards for the presence of OTA-producing black aspergilli. © 2013 The Society for Applied Microbiology.

Characterization of nonochratoxigenic strains of Aspergillus carbonarius from grapes.

PubMed

Cabañes, F J; Bragulat, M R; Castellá, G

2013-12-01

Aspergillus carbonarius is the main responsible source of ochratoxin A (OTA) in food commodities such as wine, grapes or dried vine fruits from main viticultural regions worldwide. Besides, OTA production is a very consistent property of this species and for this reason atoxigenic isolates of A. carbonarius are very rarely found in natural environments. In the present study, for the first time, three nonochratoxigenic wild strains of A. carbonarius have been discovered, unambiguously identified, characterized in deep and compared to ochratoxigenic strains of the same species. In addition, polyketide synthase (pks) genes suggested to be involved in OTA biosynthesis were also screened in these strains. The identification of the strains was confirmed by ITS-5.8S rRNA, β-tubulin and calmodulin gene sequencing. The three atoxigenic strains did not produce OTA in a conducive culture medium at any of the temperatures and times of incubation tested. Five ketosynthase domains from pks genes previously described in A. carbonarius were detected both in ochratoxigenic and in nonochratoxigenic strains. Atoxigenic strains of A. carbonarius could be useful as biotechnological agents to be used in food industry and as biological agents for control of OTA production in vineyards and other crops. Copyright © 2013 Elsevier Ltd. All rights reserved.

Oxytocin receptor antagonist treatments alter levels of attachment to mothers and central dopamine activity in pre-weaning mandarin vole pups.

PubMed

He, Zhixiong; Hou, Wenjuan; Hao, Xin; Dong, Na; Du, Peirong; Yuan, Wei; Yang, Jinfeng; Jia, Rui; Tai, Fadao

2017-10-01

Oxytocin (OT) is known to be important in mother-infant bonding. Although the relationship between OT and filial attachment behavior has been studied in a few mammalian species, the effects on infant social behavior have received little attention in monogamous species. The present study examined the effects of OT receptor antagonist (OTA) treatment on attachment behavior and central dopamine (DA) activity in male and female pre-weaning mandarin voles (Microtus mandarinus). Our data showed that OTA treatments decreased the attachment behavior of pups to mothers, measured using preference tests at postnatal day 14, 16, 18 and 20. OTA treatments reduced serum OT concentration in pre-weaning pups and decreased tyrosine hydroxylase (TH) levels in the ventral tegmental area (VTA), indicating a decrease in central DA activity. In male and female pups, OTA reduced DA levels, DA 1-type receptor (D1R) and DA 2-type receptor (D2R) protein expression in the nucleus accumbens (NAcc). Our results indicate that OTA treatment inhibits the attachment of pre-weaning pups to mothers. This inhibition is possibly associated with central DA activity and levels of two types of dopamine receptor in the NAcc. Copyright © 2017 Elsevier Ltd. All rights reserved.

Natural occurrence of ochratoxin A contamination in commercial black and white pepper products.

PubMed

Jalili, M; Jinap, S; Radu, S

2010-10-01

The concentration of ochratoxin A (OTA) in 120 commercial pepper (84 pre-packed and 36 bulk samples), which consist of local and imported white and black pepper in powder and seed form in Malaysia were determined. The objective of the study was to investigate and compare OTA concentration in black pepper and white pepper being commercialized in Malaysia. Determination method was based on HPLC with fluorescence detection coupled with immunoaffinity column clean-up step. Mobile phase consisted of acetonitrile-water-acetic acid (49.5:49.5:1.0, v/v/v), and flow rate was 1 ml/min. The LOD was 0.02 ng/g, and the average recovery values of OTA ranged from 79.5 to 92.0% in black pepper and 81.2-90.3% in white pepper. A total of 57 samples (47.5%) were contaminated with OTA ranging from 0.15 to 13.58 ng/g. The results showed that there was a significant difference between type of pepper and brands. OTA concentration in black pepper was significantly higher than white pepper (p < 0.05). The highest concentration of ochratoxin, 13.58 ng/g, was detected in a sample of black pepper seed followed by 12.64 ng/g in a sample of black pepper powder, both were bulk samples purchased from open market.

Designing an Inverter-based Operational Transconductance Amplifier-capacitor Filter with Low Power Consumption for Biomedical Applications

PubMed Central

Yousefinezhad, Sajad; Kermani, Saeed; Hosseinnia, Saeed

2018-01-01

The operational transconductance amplifier-capacitor (OTA-C) filter is one of the best structures for implementing continuous-time filters. It is particularly important to design a universal OTA-C filter capable of generating the desired filter response via a single structure, thus reducing the filter circuit power consumption as well as noise and the occupied space on the electronic chip. In this study, an inverter-based universal OTA-C filter with very low power consumption and acceptable noise was designed with applications in bioelectric and biomedical equipment for recording biomedical signals. The very low power consumption of the proposed filter was achieved through introducing bias in subthreshold MOSFET transistors. The proposed filter is also capable of simultaneously receiving favorable low-, band-, and high-pass filter responses. The performance of the proposed filter was simulated and analyzed via HSPICE software (level 49) and 180 nm complementary metal-oxide-semiconductor technology. The rate of power consumption and noise obtained from simulations are 7.1 nW and 10.18 nA, respectively, so this filter has reduced noise as well as power consumption. The proposed universal OTA-C filter was designed based on the minimum number of transconductance blocks and an inverter circuit by three transconductance blocks (OTA). PMID:29535925

An OTA-C filter for ECG acquisition systems with highly linear range and less passband attenuation

NASA Astrophysics Data System (ADS)

Jihai, Duan; Chuang, Lan; Weilin, Xu; Baolin, Wei

2015-05-01

A fifth order operational transconductance amplifier-C (OTA-C) Butterworth type low-pass filter with highly linear range and less passband attenuation is presented for wearable bio-telemetry monitoring applications in a UWB wireless body area network. The source degeneration structure applied in typical small transconductance circuit is improved to provide a highly linear range for the OTA-C filter. Moreover, to reduce the passband attenuation of the filter, a cascode structure is employed as the output stage of the OTA. The OTA-based circuit is operated in weak inversion due to strict power limitation in the biomedical chip. The filter is fabricated in a SMIC 0.18-μm CMOS process. The measured results for the filter have shown a passband gain of -6.2 dB, while the -3-dB frequency is around 276 Hz. For the 0.8 VPP sinusoidal input at 100 Hz, a total harmonic distortion (THD) of -56.8 dB is obtained. An electrocardiogram signal with noise interference is fed into this chip to validate the function of the designed filter. Project supported by the National Natural Science Foundation of China (Nos. 61161003, 61264001, 61166004) and the Guangxi Natural Science Foundation (No. 2013GXNSFAA019333).

Designing an Inverter-based Operational Transconductance Amplifier-capacitor Filter with Low Power Consumption for Biomedical Applications.

PubMed

Yousefinezhad, Sajad; Kermani, Saeed; Hosseinnia, Saeed

2018-01-01

The operational transconductance amplifier-capacitor (OTA-C) filter is one of the best structures for implementing continuous-time filters. It is particularly important to design a universal OTA-C filter capable of generating the desired filter response via a single structure, thus reducing the filter circuit power consumption as well as noise and the occupied space on the electronic chip. In this study, an inverter-based universal OTA-C filter with very low power consumption and acceptable noise was designed with applications in bioelectric and biomedical equipment for recording biomedical signals. The very low power consumption of the proposed filter was achieved through introducing bias in subthreshold MOSFET transistors. The proposed filter is also capable of simultaneously receiving favorable low-, band-, and high-pass filter responses. The performance of the proposed filter was simulated and analyzed via HSPICE software (level 49) and 180 nm complementary metal-oxide-semiconductor technology. The rate of power consumption and noise obtained from simulations are 7.1 nW and 10.18 nA, respectively, so this filter has reduced noise as well as power consumption. The proposed universal OTA-C filter was designed based on the minimum number of transconductance blocks and an inverter circuit by three transconductance blocks (OTA).

Malignant melanoma of the choroid in a naevus of Ota.

PubMed

Singh, M; Kaur, B; Annuar, N M

1988-02-01

A rare case of choroidal malignant melanoma in a naevus of Ota is described. This is the first reported case from Asia outside the Japanese population. This case illustrates the need for close observation of all pigmented lesions of the eye.

Efficacy of different caffeine concentrations on growth and ochratoxin A production by Aspergillus species.

PubMed

Akbar, A; Medina, A; Magan, N

2016-07-01

The objective of this study was to evaluate the effect of different caffeine concentrations (0-4%) on (i) lag phase prior to growth, (ii) growth rates and (iii) ochratoxin A (OTA) production by strains from the Aspergillus section Circumdati and Aspergillus section Nigri groups, isolated from coffee, when grown on a conducive medium at 0·98 water activity and 30°C. The lag phases prior to growth increased with caffeine concentration. A strain of Aspergillus niger and Aspergillus carbonarius were the most sensitive to caffeine with growth being inhibited by <1% caffeine. For strains of Aspergillus westerdijkiae, Aspergillus ochraceus and Aspergillus steynii, although growth was inhibited significantly, some growth (10-15% of controls) occurred in 4% caffeine. OTA production was significantly inhibited by only 0·5% caffeine for strains of A. westerdijkiae, A. niger and A. carbonarius. For A. steynii at least 1·5% caffeine was required to inhibit OTA production. In contrast, for the strain of A. ochraceus there was a stimulation of OTA at 3% with a reduction at 4% caffeine. These results are discussed in the context of the different concentrations of caffeine found in Arabica and Robusta coffee and the development of minimization strategies. Arabic (0·6%) and Robusta coffee (4%) have significantly different amounts of endogenous caffeine. The growth of six ochratoxigenic fungi which contaminate coffee with ochratoxin A (OTA) had differential tolerance/sensitivity to concentrations of caffeine in vitro in this range. However, low concentrations of caffeine (<0·5%) was inhibitory to OTA production. These results are discussed in the context of the potential for using such information for the design of minimization strategies to control mycotoxin production in such products. © 2016 The Society for Applied Microbiology.

Toxicological interactions between mycotoxins from ubiquitous fungi: Impact on hepatic and intestinal human epithelial cells.

PubMed

Sobral, M Madalena C; Faria, Miguel A; Cunha, Sara C; Ferreira, Isabel M P L V O

2018-07-01

Aflatoxin B1 (AFB1), deoxynivalenol (DON), fumonisin B1 (FB1) and ochratoxin A (OTA) are toxic fungal metabolites co-occurring naturally in the environment. This study aimed to evaluate the toxicological interactions of these mycotoxins concerning additive, antagonistic and synergistic toxicity towards human cells. The theoretical biology-based Combination index-isobologram method was used to evaluate the individual and binary effect of these toxins and determine the type of the interaction using as models Caco-2 (intestinal) and HepG2 (hepatic) cells. Cytotoxicity was assessed using the MTT test at the concentrations of 0.625-20 μM for all the compounds. DON exerted the highest toxicity toward both cells, OTA and AFB1 also showed a dose-effect response, whereas no toxicity was verified for FB1. Synergism or antagonism effects occurred when exposing AFB1-DON and AFB1-OTA on Caco-2 cells at higher or lower concentrations, respectively; while DON-OTA showed synergism throughout all inhibition levels. Concerning HepG2, AFB1-DON exerted a strong synergism, regardless of the level; whereas AFB1-OTA had slight synergism/nearly additive effect; and, OTA-DON had a moderate antagonism/nearly additive effect. Synergistic strengths as high as a dose reduction index of 10 for AFB1-DON were observed in hepatic cells. Taken together our findings indicate that the toxicological effects differ regarding the type of mycotoxins used for combinations and the stronger synergistic effect was observed for mixtures containing DON in both cells. Therefore, even though DON has not been classified as to its carcinogenicity to humans, this mycotoxin may present a serious threat to health, mainly when co-occurring in the environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Proteome analysis of the fungus Aspergillus carbonarius under ochratoxin A producing conditions.

PubMed

Crespo-Sempere, A; Gil, J V; Martínez-Culebras, P V

2011-06-30

Aspergillus carbonarius is an important ochratoxin A producing fungus that is responsible for mycotoxin contamination of grapes and wine. In this study, the proteomes of highly (W04-40) and weakly (W04-46) OTA-producing A. carbonarius strains were compared to identify proteins that may be involved in OTA biosynthesis. Protein samples were extracted from two biological replicates and subjected to two dimensional gel electrophoresis analysis and mass spectrometry. Expression profile comparison (PDQuest software), revealed 21 differential spots that were statistically significant and showed a two-fold change in expression, or greater. Among these, nine protein spots were identified by MALDI-MS/MS and MASCOT database and twelve remain unidentified. Of the identified proteins, seven showed a higher expression in strain W04-40 (high OTA producer) and two in strain W04-46 (low OTA producer). Some of the identified amino acid sequences shared homology with proteins involved in regulation, amino acid metabolism, oxidative stress and sporulation. It is worth noting the presence of a protein with 126.5 fold higher abundance in strain W04-40 showing homology with protein CipC, a protein with unknown function related with pathogenesis and mycotoxin production by some authors. Variations in protein expression were also further investigated at the mRNA level by real-time PCR analysis. The mRNA expression levels from three identified proteins including CipC showed correlation with protein expression levels. This study represents the first proteomic analysis for a comparison of two A. carbonarius strains with different OTA production and will contribute to a better understanding of the molecular events involved in OTA biosynthesis. Copyright © 2011 Elsevier B.V. All rights reserved.

Bibliography on Cold Regions Science and Technology. Volume 52. Part 2,

DTIC Science & Technology

1998-12-01

eng] 52-5087 spheric gases from antarctic ice cores. Gillaik, T., et al, in sediments and biota from four US arctic lakes. Allen-Gil, Study of the...1996,eng] 52-2678 52-690 Solomon , S., et at, [1997,eng] 52-879 Studies of cloud ice water path and optical thickness during Homogeneous ice...of clouds: a wave ota, D., et al, [1995,eng] 52-5364 flash rate. Solomon , R.C., [1997,eng] 52-1070 cloud case study . Ackerman, S.A., et al, [1998,eng

Zeolite Linde Type L as micro-solid phase extraction sorbent for the high performance liquid chromatography determination of ochratoxin A in coffee and cereal.

PubMed

Lee, Tien Ping; Saad, Bahruddin; Ng, Eng Poh; Salleh, Baharuddin

2012-05-11

Zeolite Linde Type L (LTL) crystals with different length, diameter and particle size (nanosized LTL, rod LTL, cylinder LTL and needle LTL) were synthesized, characterized and were used as sorbent in the micro-solid phase extraction of ochratoxin A (OTA) before the high performance liquid chromatography detection. Under the optimized conditions, the detection limits of OTA for coffee and cereal were 0.09 ng g(-1) and 0.03 ng g(-1), respectively, while the quantification limits were 0.28 ng g(-1) and 0.08 ng g(-1), respectively. The recoveries of OTA of coffee and cereal spiked at 0.5, 10 and 25 ng g(-1) ranged from 91.7 to 101.0%. The proposed method was applied to forty-five samples of coffee and cereal. The presence of OTA was found in twenty-five samples, ranging from 0.28 to 9.33 ng g(-1). Copyright © 2012 Elsevier B.V. All rights reserved.

Label-Free QCM Immunosensor for the Detection of Ochratoxin A

PubMed Central

Ertekin, Özlem; Laguna, Duygu Ercan; Özen, Fehime Şeyma; Öztürk, Zafer Ziya; Öztürk, Selma

2018-01-01

Ochratoxin A (OTA) is a potent mycotoxin that poses a risk in food and feed moieties and subject to worldwide regulation. Laboratory-based analytical methods are traditionally employed for reliable OTA quantification, but these methods cannot provide rapid and on-site analysis, where biosensors fill this gap. In this study a label-free quartz crystal microbalance (QCM)-based immunosensor for the detection of OTA, which is one of the most important small molecule contaminants, was developed by direct immobilization of OTA to amine-bearing sensor surfaces using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)/N-Hydroxysuccinimide (NHS) chemistry. The protein-free sensor surface enabled regeneration of sensor surface with 50 mM NaOH and 1% SDS up to 13 times without loss of performance, which would disrupt a protein-containing sensor surface. We developed a QCM immunosensor using the developed sensor surface with a 17.2–200 ng/mL detection range which can be used for on-site detection of feedstuffs. PMID:29641432

Label-Free QCM Immunosensor for the Detection of Ochratoxin A.

PubMed

Pirinçci, Şerife Şeyda; Ertekin, Özlem; Laguna, Duygu Ercan; Özen, Fehime Şeyma; Öztürk, Zafer Ziya; Öztürk, Selma

2018-04-11

Ochratoxin A (OTA) is a potent mycotoxin that poses a risk in food and feed moieties and subject to worldwide regulation. Laboratory-based analytical methods are traditionally employed for reliable OTA quantification, but these methods cannot provide rapid and on-site analysis, where biosensors fill this gap. In this study a label-free quartz crystal microbalance (QCM)-based immunosensor for the detection of OTA, which is one of the most important small molecule contaminants, was developed by direct immobilization of OTA to amine-bearing sensor surfaces using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)/N-Hydroxysuccinimide (NHS) chemistry. The protein-free sensor surface enabled regeneration of sensor surface with 50 mM NaOH and 1% SDS up to 13 times without loss of performance, which would disrupt a protein-containing sensor surface. We developed a QCM immunosensor using the developed sensor surface with a 17.2-200 ng/mL detection range which can be used for on-site detection of feedstuffs.

Coffee silverskin: characterization, possible uses, and safety aspects.

PubMed

Toschi, Tullia Gallina; Cardenia, Vladimiro; Bonaga, Giorgio; Mandrioli, Mara; Rodriguez-Estrada, Maria Teresa

2014-11-05

The reuse of coffee silverskin (CS), the main waste product of the coffee-roasting industry, could be an alternative to its environmental disposal. However, CS could also contain undesirable compounds, such as ochratoxin A (OTA) and phytosterol oxidation products (POPs). A study on the composition of CS (caffeine, moisture, dietary fibers, carbohydrates, and polyphenol contents) was carried out, with emphasis on OTA and POPs for safety reasons. The lipid fraction showed significant amounts of linoleic acid and phytosterols (7.0 and 12.1% of lipid fraction). Noticeable levels of POPs (114.11 mg/100 g CS) were found, and the phytosterol oxidation rate varied from 27.6 to 48.1%. The OTA content was 18.7-34.4 μg/kg CS, which is about 3 times higher than the European Commission limits for coffee products. The results suggest that CS could be used as a source of cellulose and/or bioactive compounds; however, the contents of POPs and OTA might represent a risk for human safety if intended for human or livestock use.

The WIYN One Degree Imager - Status and Performance

NASA Astrophysics Data System (ADS)

Boroson, Todd A.

2013-06-01

A preliminary version of the WIYN One Degree Imager (ODI) has been commissioned and put into scientific operation. ODI was designed to take advantage of the excellent image quality and wide field of view of the WIYN 3.5m telescope. It will do this by covering a one square degree focal plane with orthogonal transfer array (OTA) detectors, which have the capability to correct for image motion during the exposure in regions approximately the size of the isokinetic patch. The partial ODI (pODI) differs from the complete ODI in two ways - only 13 of the 64 OTAs populate the focal plane, and only coherent image motion correction is enabled. However, this implementation has allowed the commissioning of the instrument with all subsystems except the additional detectors in place. The 13 OTAs are configured as a 24 X 24 arcminute “science field”, plus 4 outer OTAs, allowing the sampling of all radii within the one square degree field. pODI is now in use for science observations as we prepare to upgrade the focal plane. The performance of pODI is excellent. Image quality is site seeing limited, and, on good seeing nights, we can achieve images around 0.4 arcsec FWHM over the entire field. The guide signal, from selected regions in the outer OTAs, can be passed to the telescope exclusively, or the high frequency component can be applied as a global shift to the OTAs. We are still in the process of characterizing the gains from this coherent correction, but the detectors perform well in this mode. Data are immediately transferred to an archive at Indiana University, where they are pipeline-processed to remove instrumental signature. The OTA detectors perform adequately in terms of read noise, full well, sensitivity, and dark current. They show 2 anomalies: (1) regions in the circuitry outside the imaging area glow under certain circumstances, and (2) a low level degradation of charge transfer efficiency is present between the imaging area and the serial registers. We have found ways to address both of these effects in operation, calibration, and post-processing, and the instrument is producing valuable scientific observations.

Topical application of ochratoxin A causes DNA damage and tumor initiation in mouse skin.

PubMed

Kumar, Rahul; Ansari, Kausar M; Chaudhari, Bhushan P; Dhawan, Alok; Dwivedi, Premendra D; Jain, Swatantra K; Das, Mukul

2012-01-01

Skin cancer is one of the most common forms of cancer and 2-3 million new cases are being diagnosed globally each year. Along with UV rays, environmental pollutants/chemicals including mycotoxins, contaminants of various foods and feed stuffs, could be one of the aetiological factors of skin cancer. In the present study, we evaluated the DNA damaging potential and dermal carcinogenicity of a mycotoxin, ochratoxin A (OTA), with the rationale that dermal exposure to OTA in workers may occur during their involvement in pre and post harvest stages of agriculture. A single topical application of OTA (20-80 µg/mouse) resulted in significant DNA damage along with elevated γ-H2AX level in skin. Alteration in oxidative stress markers such as lipid peroxidation, protein carbonyl, glutathione content and antioxidant enzymes was observed in a dose (20-80 µg/mouse) and time-dependent (12-72 h) manner. The oxidative stress was further emphasized by the suppression of Nrf2 translocation to nucleus following a single topical application of OTA (80 µg/mouse) after 24 h. OTA (80 µg/mouse) application for 12-72 h caused significant enhancement in- (a) reactive oxygen species generation, (b) activation of ERK1/2, p38 and JNK MAPKs, (c) cell cycle arrest at G0/G1 phase (37-67%), (d) induction of apoptosis (2.0-11.0 fold), (e) expression of p53, p21/waf1, (f) Bax/Bcl-2 ratio, (g) cytochrome c level, (h) activities of caspase 9 (1.2-1.8 fold) and 3 (1.7-2.2 fold) as well as poly ADP ribose polymerase cleavage. In a two-stage mouse skin tumorigenesis protocol, it was observed that a single topical application of OTA (80 µg/mouse) followed by twice weekly application of 12-O-tetradecanoylphorbol-13-acetate for 24 week leads to tumor formation. These results suggest that OTA has skin tumor initiating property which may be related to oxidative stress, MAPKs signaling and DNA damage.

Nevus of Ota (oculodermal melanocytosis) in a dog.

PubMed

Malho, Pedro; Shea, Anita; Donaldson, David

2018-05-01

A 5-year-old, female, spayed Rhodesian Ridgeback presented with ocular melanocytosis and skin hyperpigmentation involving the distribution of the first and second divisions of the trigeminal nerve on the right side of the face. The dermatomal pattern of the hyperpigmentation was similar to nevus of Ota or oculodermal melanocytosis reported in humans. This condition has been associated with increased risk of developing secondary glaucoma and melanoma transformation in skin, ocular, orbital tissues, and the central nervous system. The clinical investigation and description of oculodermal melanocytosis (nevus of Ota) are presented for the first time in the dog. © 2017 American College of Veterinary Ophthalmologists.

Malignant melanoma of the choroid in a naevus of Ota.

PubMed Central

Singh, M.; Kaur, B.; Annuar, N. M.

1988-01-01

A rare case of choroidal malignant melanoma in a naevus of Ota is described. This is the first reported case from Asia outside the Japanese population. This case illustrates the need for close observation of all pigmented lesions of the eye. Images PMID:3349013

Co-occurrence of citrinin and ochratoxin A in rice in Asia and its implications for human health.

PubMed

Ali, Nurshad

2018-04-01

Citrinin (CIT) and ochratoxin A (OTA) are nephrotoxic mycotoxins, produced by several Aspergillus and Penicillium species and their co-occurrence in rice may cause health effects in humans. Rice is an important food crop worldwide and is a major staple food in Asia which may be invaded by CIT and OTA producing fungal spores in the field, during harvest and storage. Humans are exposed to these mycotoxins through ingestion of contaminated rice and other food commodities. Yet, data on the combined presence to these food contaminants are still insufficient to estimate human exposure in Asia. This review describes the prevalence of CIT and OTA in rice in Asia and its implications on human health, which may help in establishing and carrying out proper management strategies against mould development on rice. From the health point of view, combined exposition of CIT and OTA should be a public concern as both are nephrotoxic and long-term exposure can pose detrimental health effects. Thus, it is necessary for local farmers and food factories to implement strict measures and to improve methods for rice preservation during the distribution to consumers, particularly in the markets. Moreover, regular surveys for CIT and OTA occurrence in rice and human biomonitoring are recommended to reduce the health effects in Asian population. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Polyaniline Langmuir-Blodgett film based aptasensor for ochratoxin A detection.

PubMed

Prabhakar, Nirmal; Matharu, Zimple; Malhotra, B D

2011-06-15

Ochratoxin A (OTA) produced by Aspergillus Ochraceus and Penicillium verrucosum is a very dangerous toxin due to its toxic effects in human beings and its presence in a wide range of food products and cereals. A Langmuir-Blodgett (polyaniline (PANI)-stearic acid (SA)) film based highly sensitive and robust impedimetric aptasensor has been developed for ochratoxin A (OTA) detection. DNA Aptamer (Apt-DNA) specific to OTA has been covalently immobilized onto mixed Langmuir-Blodgett (LB) monolayer comprising of PANI-SA deposited onto indium tin-oxide (ITO) coated glass plates. This Apt-DNA/PANI-SA/ITO aptaelectrode has been characterized using scanning electron microscopy, Fourier transform-infrared spectroscopy, contact angle measurements, cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The Apt-DNA/PANI-SA/ITO aptasensor shows detection of OTA by electrochemical impedance spectroscopy in the linear range of 0.0001 μg/ml (0.1 ng/ml) to 0.01 μg/ml (10 ng/ml) and 1 μg/ml-25 μg/ml with detection limit of 0.1 ng/ml in 15 min. The Apt-DNA/PANI-SA/ITO aptasensor can be reused ∼13 times. The binding or affinity constant (K(a)) of aptamer with OTA, calculated using Langmuir adsorption isotherm, is found be 1.21×10(7) M(-1). Copyright © 2011 Elsevier B.V. All rights reserved.

Comparison of Clean-Up Methods for Ochratoxin A on Wine, Beer, Roasted Coffee and Chili Commercialized in Italy

PubMed Central

Prelle, Ambra; Spadaro, Davide; Denca, Aleksandra; Garibaldi, Angelo; Gullino, Maria Lodovica

2013-01-01

The most common technique used to detect ochratoxin A (OTA) in food matrices is based on extraction, clean-up, and chromatography detection. Different clean-up cartridges, such as immunoaffinity columns (IAC), molecular imprinting polymers (MIP), Mycosep™ 229, Mycospin™, and Oasis® HLB (Hydrophilic Lipophilic balance) as solid phase extraction were tested to optimize the purification for red wine, beer, roasted coffee and chili. Recovery, reproducibility, reproducibility, limit of detection (LOD) and limit of quantification (LOQ) were calculated for each clean-up method. IAC demonstrated to be suitable for OTA analysis in wine and beer with recovery rate >90%, as well as Mycosep™ for wine and chili. On the contrary, MIP columns were the most appropriate to clean up coffee. A total of 120 samples (30 wines, 30 beers, 30 roasted coffee, 30 chili) marketed in Italy were analyzed, by applying the developed clean-up methods. Twenty-seven out of 120 samples analyzed (22.7%: two wines, five beers, eight coffees, and 12 chili) resulted positive to OTA. A higher incidence of OTA was found in chili (40.0%) more than wine (6.6%), beers (16.6%) and coffee (26.6%). Moreover, OTA concentration in chili was the highest detected, reaching 47.8 µg/kg. Furthermore, three samples (2.5%), two wines and one chili, exceeded the European threshold. PMID:24152987

Effect of dissolved oxygen on the corrosion behavior of 304 SS in 0.1 N nitric acid containing chloride

NASA Astrophysics Data System (ADS)

Khobragade, Nilay N.; Bansod, Ankur V.; Patil, Awanikumar P.

2018-04-01

A study was undertaken in several selected mixed nitric acid/chloride ({{{{NO}}}3}-/{{{Cl}}}- ratio) electrolytes with the nitric acid concentration of 0.1 N and chloride concentration of 0, 10, 100, 1000 and 10 000 ppm. Electrochemical tests like potentiodynamic polarization test, electrochemical impedance spectroscopy (EIS) and Mott-Schottky analysis (M-S) were carried out when the electrolytes were in deaerated condition and were in open to air (OTA) condition, and the effect of dissolved oxygen was evaluated on the corrosion behavior of 304 SS. It was found that at a critical {{{{NO}}}3}-/{{{Cl}}}- ratio, a passive state is attained at the earliest in OTA condition. Also, the passive film resistance showed higher values in OTA condition than in deaerated condition exhibiting the effect of dissolved oxygen. The results of EIS results confirmed the results obtained by potentiodynamic polarization wherein the low passive current densities were obtained in OTA condition. Mott-Schottky analysis revealed the lowest defect densities in 100 ppm Cl‑ solution in OTA condition and in 10 ppm Cl‑ solution in deaerated condition indicating less defective films formed in these solutions. XPS analysis showed that the film was bilayer in nature in confirmation with M-S analysis. The results were discussed with point defect model (PDM) and by competitive surface adsorption.

Medial posterior choroidal artery territory infarction associated with tumor removal in the pineal/tectum/thalamus region through the occipital transtentorial approach.

PubMed

Saito, Ryuta; Kumabe, Toshihiro; Kanamori, Masayuki; Sonoda, Yukihiko; Mugikura, Shunji; Takahashi, Shoki; Tominaga, Teiji

2013-08-01

Damage to the deep venous system, occipital lobe, and/or corpus callosum is well known to cause complications associated with the occipital transtentorial approach (OTA), but ischemic complications are not well documented. The authors investigated the high incidences of ischemic complications associated with removal of pineal/tectal/thalamic tumors through the OTA. Clinical records of 29 patients who underwent 31 surgeries using the OTA from December 2001 to May 2011 were retrospectively studied. Tumor locations were the pineal/tectal/thalamic region for 19, cerebellum for 7, and medial temporal lobe for 3. Postoperative diffusion-weighted magnetic resonance images obtained within 72 h after surgery detected infarction in the tectal/splenial/thalamic region, presumably representing the medial posterior choroidal artery (MPChA) territory, in 10 patients. All these patients had tumor in the pineal/tectal/thalamic region. Deteriorated or newly developed eye symptoms including vertical gaze palsy tended to persist in these patients compared to those without ischemic complications. A relatively high incidence of MPChA territory infarction was associated with removal of tumors in the pineal/tectal/thalamic region through the OTA. Eye symptoms often occurred post-surgery and tended to persist in these patients. Neurosurgeons must be aware of the possibility of MPChA territory infarction to further increase the safety of the OTA. Copyright © 2012 Elsevier B.V. All rights reserved.

Silver Nanoparticle-Based Fluorescence-Quenching Lateral Flow Immunoassay for Sensitive Detection of Ochratoxin A in Grape Juice and Wine.

PubMed

Jiang, Hu; Li, Xiangmin; Xiong, Ying; Pei, Ke; Nie, Lijuan; Xiong, Yonghua

2017-02-28

A silver nanoparticle (AgNP)-based fluorescence-quenching lateral flow immunoassay with competitive format (cLFIA) was developed for sensitive detection of ochratoxin A (OTA) in grape juice and wine samples in the present study. The Ru(phen) 3 2 + -doped silica nanoparticles (RuNPs) were sprayed on the test and control line zones as background fluorescence signals. The AgNPs were designed as the fluorescence quenchers of RuNPs because they can block the exciting light transferring to the RuNP molecules. The proposed method exhibited high sensitivity for OTA detection, with a detection limit of 0.06 µg/L under optimized conditions. The method also exhibited a good linear range for OTA quantitative analysis from 0.08 µg/L to 5.0 µg/L. The reliability of the fluorescence-quenching cLFIA method was evaluated through analysis of the OTA-spiked red grape wine and juice samples. The average recoveries ranged from 88.0% to 110.0% in red grape wine and from 92.0% to 110.0% in grape juice. Meanwhile, less than a 10% coefficient variation indicated an acceptable precision of the cLFIA method. In summary, the new AgNP-based fluorescence-quenching cLFIA is a simple, rapid, sensitive, and accurate method for quantitative detection of OTA in grape juice and wine or other foodstuffs.

Estimation of water balance in two forests dominated, steep catchments of western Japan, using SWAT model

NASA Astrophysics Data System (ADS)

Admajaya, F. T.; Onodera, S. I.; Shimizu, Y.; Saito, M.

2017-12-01

To estimate hydrological responses under various meteorological conditions in forests dominated, steep catchments, it is necessary to apply the model approach. The purpose of this study is to estimate water balance in Ota river and Gonokawa river watersheds, using SWAT Model. SWAT-CUP SUFI2 was used for model calibration for five years (2006-2010) and validation periods of four years (2011-2014). Evapotranspiration was estimated by the Penman-Monteith method. The water balance of the Ota river and Gonokawa river have been analyzed for last nine years. The results of the daily calibration period were ranging between satisfactory to very good. The mean annual water balance for long-term period and monthly seasonal variation in two catchments were similar as follows, precipitation, evapotranspiration, discharge, and groundwater recharge were 1,852.7 mm, 718.8 mm (38.8% of the precipitation), 776.3 mm (41.9%), and 358.2 mm (19.2%), and seasonal variation pattern of water balance which summer season was high, respectively. The difference of seasonal variations and annual variation between a flood and a drought year of Ota river and Gono river was slightly big. Decreasing rates of precipitation during a drought year was 23% in Ota river as compared with 18% in Gono river catchments. In addition, the decreasing rate in river discharge was 43% in Ota river, but 36% in Gono river

Silver Nanoparticle-Based Fluorescence-Quenching Lateral Flow Immunoassay for Sensitive Detection of Ochratoxin A in Grape Juice and Wine

PubMed Central

Jiang, Hu; Li, Xiangmin; Xiong, Ying; Pei, Ke; Nie, Lijuan; Xiong, Yonghua

2017-01-01

A silver nanoparticle (AgNP)-based fluorescence-quenching lateral flow immunoassay with competitive format (cLFIA) was developed for sensitive detection of ochratoxin A (OTA) in grape juice and wine samples in the present study. The Ru(phen)32+-doped silica nanoparticles (RuNPs) were sprayed on the test and control line zones as background fluorescence signals. The AgNPs were designed as the fluorescence quenchers of RuNPs because they can block the exciting light transferring to the RuNP molecules. The proposed method exhibited high sensitivity for OTA detection, with a detection limit of 0.06 µg/L under optimized conditions. The method also exhibited a good linear range for OTA quantitative analysis from 0.08 µg/L to 5.0 µg/L. The reliability of the fluorescence-quenching cLFIA method was evaluated through analysis of the OTA-spiked red grape wine and juice samples. The average recoveries ranged from 88.0% to 110.0% in red grape wine and from 92.0% to 110.0% in grape juice. Meanwhile, less than a 10% coefficient variation indicated an acceptable precision of the cLFIA method. In summary, the new AgNP-based fluorescence-quenching cLFIA is a simple, rapid, sensitive, and accurate method for quantitative detection of OTA in grape juice and wine or other foodstuffs. PMID:28264472

A retrospective analysis of the clinical efficacies of Q-switched Alexandrite and Q-switched Nd:YAG lasers in the treatment of nevus of Ota in Korean patients.

PubMed

Choi, Jae Eun; Lee, Joo Bong; Park, Ki Beom; Kim, Bang Soon; Yeo, Un-Cheol; Huh, Chang Hun; Kim, Jie Hoon; Kye, Young Chul

2015-06-01

While the Q-switched Alexandrite laser (QSAL) and the Q-switched neodymium: yttrium-aluminum-garnet (QSNY) laser have been widely used in treating nevus of Ota, few studies compared them. To compare the efficacies of the QSAL and the QSNY laser in the treatment of nevus of Ota in Korean patients. A retrospective multicenter study was conducted in 76 patients with nevus of Ota. Thirty-one patients were treated with a QSAL (5.5-8.0 J/cm(2), 4-mm spot size) and 45 patients were treated with QSNY laser (6.0-12.0 J/cm(2), 2-mm spot size). Treatment outcomes were categorized into five grades and the results were compared with the relevant variables taken into account using multivariate logistic regression analysis. QSAL treatment was more likely to achieve a better response compared with that with QSNY laser treatment. The odds ratio of achieving an excellent response, compared with the odds ratio of having a poor response, was 12.213-times more likely when a QSAL was used than when a QSNY laser was used (p = 0.026). The QSAL tends to be more efficient than the QSNY laser in the treatment of nevus of Ota in Korean patients. Further controlled, prospective comparison studies are needed.

Gel-based immunotest for simultaneous detection of 2,4,6-trichlorophenol and ochratoxin A in red wine.

PubMed

Beloglazova, N V; Goryacheva, I Yu; Rusanova, T Yu; Yurasov, N A; Galve, R; Marco, M-P; De Saeger, S

2010-07-05

A new rapid method which allows simultaneous one step detection of two analytes of different nature (2,4,6,-trichlorophenol (TCP) and ochratoxin A (OTA)) in red wine was developed. It was based on a column test with three separate immunolayers: two test layers and one control layer. Each layer consisted of sepharose gel with immobilized anti-OTA (OTA test layer), anti-TCP (TCP test layer) or anti-HRP (control layer) antibodies. Analytes bind to the antibodies in the corresponding test layer while sample flows through the column. Then a mixture of OTA-HRP and TCP-HRP in appropriate dilutions was used, followed by the application of chromogenic substrate. Colour development of the test layer occurred when the corresponding analyte was absent in the sample. HRP-conjugates bound to anti-HRP antibody in the control layer independently of presence or absence of analytes and a blue colour developed in the control layer. Cut-off values for both analytes were 2 microg L(-1). The described method was applied to the simultaneous detection of TCP and OTA in wine samples. To screen the analytes in red wine samples, clean-up columns were used for sample pre-treatment in combination with the test column. Results were confirmed by chromatographic methods. Copyright 2010 Elsevier B.V. All rights reserved.

Detection of Ochratoxin a Using Molecular Beacons and Real-Time PCR Thermal Cycler

PubMed Central

Sanzani, Simona Marianna; Reverberi, Massimo; Fanelli, Corrado; Ippolito, Antonio

2015-01-01

We developed a simple and cheap assay for quantitatively detecting ochratoxin A (OTA) in wine. A DNA aptamer available in literature was used as recognition probe in its molecular beacon form, i.e., with a fluorescence-quenching pair at the stem ends. Our aptabeacon could adopt a conformation allowing OTA binding, causing a fluorescence rise due to the increased distance between fluorophore and quencher. We used real-time PCR equipment for capturing the signal. With this assay, under optimized conditions, the entire process can be completed within 1 h. In addition, the proposed system exhibited a good selectivity for OTA against other mycotoxins (ochratoxin B and aflatoxin M1) and limited interference from aflatoxin B1 and patulin. A wide linear detection range (0.2–2000 µM) was achieved, with LOD = 13 nM, r = 0.9952, and R2 = 0.9904. The aptabeacon was also applied to detect OTA in red wine spiked with the same dilution series. A linear correlation with a LOD = 19 nM, r = 0.9843, and R2 = 0.9708 was observed, with recoveries in the range 63%–105%. Intra- and inter-day assays confirmed its reproducibility. The proposed biosensor, although still being finalized, might significantly facilitate the quantitative detection of OTA in wine samples, thus improving their quality control from a food safety perspective. PMID:25760080

Effect of oxidant stressors and phenolic antioxidants on the ochratoxigenic fungus aspergillus carbonarius

USDA-ARS?s Scientific Manuscript database

In this work, the effect of oxidant stressors (hydrogen peroxide, menadione) and antioxidants (BHT, phenolic antioxidants) on growth, ROS generation, OTA production and gene expression of antioxidant enzymes of A. carbonarius was studied. In comparison to a nontoxigenic strain, an OTA-producing A. c...

Performance Standards for Secondary School Vocational Education. Background Paper.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. Office of Technology Assessment.

To assist Congress in preparing for the reauthorization of the Carl D. Perkins Vocational Education Act, the Office of Technology Assessment (OTA) examined the technical feasibility and utility of instituting specific requirements for performance measurement of secondary school vocational programs. The OTA examined two types of performance…

pH-Signaling Transcription Factor AopacC Regulates Ochratoxin A Biosynthesis in Aspergillus ochraceus.

PubMed

Wang, Yan; Liu, Fei; Wang, Liuqing; Wang, Qi; Selvaraj, Jonathan Nimal; Zhao, Yueju; Wang, Yun; Xing, Fuguo; Liu, Yang

2018-05-02

In Aspergillus and Penicillium species, an essential pH-response transcription factor pacC is involved in growth, pathogenicity, and toxigenicity. To investigate the connection between ochratoxin A (OTA) biosynthesis and ambient pH, the AopacC in Aspergillus ochraceus was functionally characterized using a loss-of-function mutant. The mycelium growth was inhibited under pH 4.5 and 10.0, while the sporulation increased under alkaline condition. A reduction of mycelium growth and an elevation of sporulation was observed in Δ AopacC mutant. Compared to neutral condition, OTA contents were respectively reduced by 71.6 and 79.8% under acidic and alkaline conditions. The expression of AopacC increased with the elevated pH, and deleting AopacC dramatically decreased OTA production and biosynthetic genes Aopks expression. Additionally, the Δ AopacC mutant exhibited attenuated infection ability toward pear fruits. These results suggest that AopacC is an alkaline-induced regulator responsible for growth and OTA biosynthesis in A. ochraceus and this regulatory mechanism might be pH-dependent.

Effect of Antioxidant Mixtures on Growth and Ochratoxin A Production of Aspergillus Section Nigri Species under Different Water Activity Conditions on Peanut Meal Extract Agar

PubMed Central

Barberis, Carla; Astoreca, Andrea; Fernandez-Juri, María Guillermina; Dalcero, Ana María; Magnoli, Carina

2010-01-01

The effect of mixtures of antioxidants butylated hydroxyanisol (BHA) and propyl paraben (PP) on lag phase, growth rate and ochratoxin A (OTA) production by four Aspergillus section Nigri strains was evaluated on peanut meal extract agar (PMEA) under different water activities (aw). The antioxidant mixtures used were: BHA + PP (mM), M1 (0.5 + 0.5), M2 (1.0 + 0.5), M3 (2.5 + 0.5), M4 (0.5 + 1.0), M5 (1.0 + 1.0), M6 (2.5 + 1.0), M7 (5.0 + 2.5) and M8 (10 + 2.5). The mixture M8 completely suppressed mycelial growth for all strains. A significant stimulation in OTA production was observed with mixtures M1 to M5 mainly at the highest aw; whereas M6, M7 and M8 completely inhibited OTA production in all strains assayed; except M6 in A. carbonarius strain (RCP G). These results could enable a future intervention strategy to minimize OTA contamination. PMID:22069644

In vitro genotoxicity of mycotoxins ochratoxin A and fumonisin B(1) could be prevented by sodium copper chlorophyllin--implication to their genotoxic mechanism.

PubMed

Domijan, Ana-Marija; Gajski, Goran; Novak Jovanović, Ivana; Gerić, Marko; Garaj-Vrhovac, Vera

2015-03-01

The aim of this study was to investigate the possible protective effect of sodium copper chlorophyllin (CHL) against cytotoxicity and DNA damage induced by mycotoxins ochratoxin A (OTA) and fumonisin B1 (FB1). CHL (0.1-100 μg/ml) alone had no impact on cell viability and genome damage in the primary human peripheral blood lymphocytes (HPBLs) and exhibited free radical scavenging activity in the DPPH assay. Both mycotoxins, OTA (4 μmol/l) and FB1 (20 μg/ml), induced DNA damage in HPBLs already after 1 h exposure. When the HPBLs were co-exposed to CHL (10 and 100 μg/ml) and OTA (4 μmol/l) or FB1 (20 μg/ml) for 1 h, CHL protected against cell and DNA damage induced by both mycotoxins, implying that OTA and FB1 cytogenotoxicity mechanisms function at least partially through oxidative stress. Therefore, CHL could be a perfect candidate for possible use as an antioxidant. Copyright © 2014 Elsevier Ltd. All rights reserved.

Acute toxicity of ochratoxin-A in marine water-reared sea bass (Dicentrarchus labrax L.).

PubMed

El-Sayed, Yasser Said; Khalil, Riad Hassan; Saad, Talaat Talaat

2009-05-01

The toxic effects of ochratoxin-A (OTA) on sea bass, Dicentrarchus labrax L., have not been previously documented. A flow-through bioassay test system was conducted in two series and a total 180 of adult marine-reared sea bass was used to estimate the acute oral 96 h median lethal concentration (LC(50)) value and behavioral changes of OTA. The data obtained were statistically evaluated using Finney's Probit Analysis Method developed by EPA. The 96 h LC(50) value for adult D. labrax was found to be 277 microg kg(-1)bwt with 95% confidence limits of 244-311 microg kg(-1)bwt. This value was calculated to be 285 microg kg(-1) bwt with Behrens-Karber's method. The two methods were relatively comparable. The acute dietary 96 h LC(50) of OTA is 9.23 mg kg(-1) diet. Additionally, the behavioral changes of sea bass were primarily observed as nervous and respiratory manifestations. We concluded that sea bass is a species highly sensitive to OTA making them a useful experimental model for aquatic mycotoxigenic problems.

Use of enzyme-linked immunosorbent assay to screen for aflatoxins, ochratoxin A, and deoxynivalenol in dry pet foods.

PubMed

Okuma, Tara A; Huynh, Thu P; Hellberg, Rosalee S

2018-03-01

The objective of this study was to perform a market survey on dry pet foods using enzyme-linked immunosorbent assay (ELISA) to detect total aflatoxins (AFs), ochratoxin A (OTA), and deoxynivalenol (DON). Pet food products (n = 58) marketed for dogs, cats, birds, and rabbits were tested in duplicate with ELISA, and results above the limit of quantitation were confirmed using liquid chromatography tandem mass spectrometry (LC-MS/MS). OTA was detected in one product (rabbit food) and AFs were detected in two products (one dog treat and one bird treat). In contrast, DON was detected in the majority (74%) of products tested. Bird and rabbit products were the most affected by DON, with levels above 0.5 μg/g in 50 and 80% of samples, respectively. One rabbit sample tested positive for both OTA and DON. Overall, the findings of this study revealed a low incidence of AFs and OTA in commercial pet food. Although DON was detected in numerous products, the levels were well below those associated with acute toxic effects.

Screening of European coffee final products for occurrence of ochratoxin A (OTA).

PubMed

vd Stegen, G; Jörissen, U; Pittet, A; Saccon, M; Steiner, W; Vincenzi, M; Winkler, M; Zapp, J; Schlatter, C

1997-04-01

Samples (633) of final coffee products were drawn from the markets of different European countries relative to the market share of each product type and brand. These samples were analysed in a cooperative action with nine different laboratories. With low limits of detection (mean detection limit approximately 0.5 ng/g) no OTA was found in over half of the samples (334 negatives). In the remaining samples occurrence of OTA at a rather low level was seen. Only four samples (all instants) exceeded a level of 10 ng/g, whereas for both instants, and roast and grounds (R & G), over three-quarters of the samples were in the range from nondetectable to 1 ng/g. The overall mean for all R & Gs was 0.8 ng/g and for all instant 1.3 ng/g (for samples in which no OTA was detected, half of the detection limit was included in this calculation). In the brewing methods frequently used in Europe the OTA is essentially fully extracted. Consumption of four cups of coffee per day (approximately 24 g R & G or approximately 8 g instant coffee) contributes on average 19 or 10 ng/day respectively. Four cups/day is above the per caput consumption level in most European contries. Compared with the Provisional Tolerable Weekly Intake (PTWI) recently set by the Joint FAO/WHO Expert Committee on Food Additives at 100 ng/kg bodyweight/week, consumption of 28 cups/week contributes up to 2% to the PTWI.

Incidence of ochratoxin A in rice and dried fruits from Rabat and Salé area, Morocco.

PubMed

Zinedine, A; Soriano, J M; Juan, C; Mojemmi, B; Moltó, J C; Bouklouze, A; Cherrah, Y; Idrissi, L; El Aouad, R; Mañes, J

2007-03-01

One hundred samples of dried fruits (20 dried raisins, 20 walnuts, 20 peanuts, 20 dried figs and 20 pistachios) and 20 samples of rice purchased from retail shops in the Rabat and Salé area in Morocco were analysed for ochratoxin A (OTA) by immunoaffinity clean-up (IAC) and liquid chromatography (LC) with fluorescence detection. The limit of quantification (LOQ) (S/N = 10:1) of OTA was 0.02 ng g(-1) in rice, 0.03 ng g(-1) in pistachio, peanut and walnut, and 0.03 ng g(-1) in dried raisins and dried figs. The incidences of occurrence of OTA in dried raisins, walnuts, peanuts, dried figs and rice were 30, 35, 25, 65 and 90%, respectively. Analytical results showed that pistachio samples contained no detectable OTA, but concentrations ranged from 0.02 +/- 0.01 to 32.4 +/- 2.10 ng g(-1) in rice, from 0.10 +/- 0.05 to 2.36 +/- 0.75 in peanut, from 0.03 +/- 0.01 to 1.42 +/- 0.45 in dried figs, from 0.05 +/- 0.02 to 4.95 +/- 0.02 in dried raisins, and from 0.04 +/- 0.01 to 0.23 +/- 0.05 in walnuts. The results also showed that 15% of the total number of rice samples analysed exceeded the 2002 regulatory limit set by European Union regulations for cereals. This is the first report on the occurrence of OTA in dried fruits and rice available in Morocco.

Ochratoxin A production in relation to ecophysiological factors by Aspergillus section Nigri strains isolated from different substrates in Argentina.

PubMed

Astoreca, A; Magnoli, C; Barberis, C; Chiacchiera, S M; Combina, M; Dalcero, A

2007-12-15

Contamination of foodstuff with mycotoxins such as ochratoxins is a major matter of concern for human and animal health. In Aspergillus species, ochratoxin synthesis depends on several environmental factors. The aims of this work were to evaluate the effect of water activity (0.995-0.85), temperature (15, 25 and 30 degrees C), incubation time (7, 14 and 21 days) and their interactions on OTA production on peanut, maize kernels, dried grapes and coffee beans meal extract agar medium by eight strains of Aspergillus section Nigri isolated from human food in Argentina. The optimum temperature for OTA production was 25 or 30 degrees C depending on the strains assayed, in most cases the highest OTA levels were achieved after 7 days of incubation, whereas this situation occurred at 15 degrees C after 14 days of incubation for only one strain. The maximum OTA level was obtained at earlier growth states when incubation temperature increased. In general, OTA concentration increased as water activity (a(W)) increased with no significant production at 0.85-0.91 a(W) under all temperature levels tested. Production occurred over a range of temperatures (15-30 degrees C) with optimum production at 30 degrees C depending on a(W) assayed. The knowledge of Aspergillus section Nigri ecophysiology is critical in the development and prediction of the risk models of raw material and final product contamination by these species under fluctuating and interacting environmental parameters.

Clustered array of ochratoxin A biosynthetic genes in Aspergillus steynii and their expression patterns in permissive conditions.

PubMed

Gil-Serna, Jessica; Vázquez, Covadonga; González-Jaén, María Teresa; Patiño, Belén

2015-12-02

Aspergillus steynii is probably the most relevant species of section Circumdati producing ochratoxin A (OTA). This mycotoxin contaminates a wide number of commodities and it is highly toxic for humans and animals. Little is known on the biosynthetic genes and their regulation in Aspergillus species. In this work, we identified and analysed three contiguous genes in A. steynii using 5'-RACE and genome walking approaches which predicted a cytochrome P450 monooxygenase (p450ste), a non-ribosomal peptide synthetase (nrpsste) and a polyketide synthase (pksste). These three genes were contiguous within a 20742 bp long genomic DNA fragment. Their corresponding cDNA were sequenced and their expression was analysed in three A. steynii strains using real time RT-PCR specific assays in permissive conditions in in vitro cultures. OTA was also analysed in these cultures. Comparative analyses of predicted genomic, cDNA and amino acid sequences were performed with sequences of similar gene functions. All the results obtained in these analyses were consistent and point out the involvement of these three genes in OTA biosynthesis by A. steynii and showed a co-ordinated expression pattern. This is the first time that a clustered organization OTA biosynthetic genes has been reported in Aspergillus genus. The results also suggested that this situation might be common in Aspergillus OTA-producing species and distinct to the one described for Penicillium species. Copyright © 2015 Elsevier B.V. All rights reserved.

Assessment of Mycotoxin Exposure in Côte d'ivoire (Ivory Coast) Through Multi-Biomarker Analysis and Possible Correlation with Food Consumption Patterns.

PubMed

Kouadio, James Halbin; Lattanzio, Veronica M T; Ouattara, Djeneba; Kouakou, Brou; Visconti, Angelo

2014-01-01

The aim of the presented study was to investigate the mycotoxin exposure of Ivorian population related to the consumption patterns of maize, peanuts, millet, and cassava product (attiéké). Maize flour samples (n = 51) were purchased from all Abidjan local markets, in the south of Ivory Coast, and urine (n = 99) was collected during the same reference period (July-September 2011) from volunteers living in Abidjan and Daloa cities. Reversed-phase liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry (LC-ESI-MS/MS) was used to analyze aflatoxins (AFB1, AFB2, AFG1, and AFG2), ochratoxin A (OTA), fumonisins (FB1, FB2), deoxynivalenol (DON), zearalenone (ZEA), and T-2 and HT-2 toxins in maize flour samples, and their relevant biomarkers (AFM1, DON, DON + de-epoxydeoxynivalenol (DOM-1), FB1, α-zearalenol (ZOL), β-ZOL, and OTA) in urine samples. Critical maize contamination was observed by AFs occurrence (total AFs 4.5 - 330.0 μg/kg) while OTA was found in 13% of samples analyzed. AFM1 was detected in 40% of urines samples (0.06 - 14.11 ng/ml), OTA in 37% (0.01 - 0.42 ng/ml), FB1 in 27% (0.07 to 15.31 ng/ml) and, DON was found in 21% of samples at levels up to 10.0 ng/ml. The correlation coefficients (R(2)) obtained by plotting the percentage of biomarker occurrence (positive samples) versus the frequency of food consumption revealed maize, peanuts, millet and attiéké were strongly linked to AFB1 and OTA exposure with values of R(2) ranged from 0.462 to 0.956. The present study provided data on mycotoxin risk in Ivory Coast, revealing a frequent co-exposure to the major mycotoxins such as AFs, OTA, and fumonisins, which appeared to be related to the frequency of peanuts, maize, millet and attiéké consumption.

Essential Oils Modulate Gene Expression and Ochratoxin A Production in Aspergillus carbonarius.

PubMed

El Khoury, Rachelle; Atoui, Ali; Verheecke, Carol; Maroun, Richard; El Khoury, Andre; Mathieu, Florence

2016-08-19

Ochratoxin A (OTA) is a mycotoxin, mainly produced on grapes by Aspergillus carbonarius, that causes massive health problems for humans. This study aims to reduce the occurrence of OTA by using the ten following essential oils (E.Os): fennel, cardamom, anise, chamomile, celery, cinnamon, thyme, taramira, oregano and rosemary at 1 µL/mL and 5 µL/mL for each E.O.As a matter of fact, their effects on the OTA production and the growth of A. carbonarius S402 cultures were evaluated, after four days at 28 °C on a Synthetic Grape Medium (SGM). Results showed that A. carbonarius growth was reduced up to 100%, when cultured with the E.Os of cinnamon, taramira, and oregano at both concentrations and the thyme at 5 µL/mL. As for the other six E.Os, their effect on A. carbonarius growth was insignificant, but highly important on the OTA production. Interestingly, the fennel E.O at 5 µL/mL reduced the OTA production up to 88.9% compared to the control, with only 13.8% of fungal growth reduction. We further investigated the effect of these E.Os on the expression levels of the genes responsible for the OTA biosynthesis (acOTApks and acOTAnrps along with the acpks gene) as well as the two regulatory genes laeA and vea, using the quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) method. The results revealed that these six E.Os reduced the expression of the five studied genes, where the ackps was downregulated by 99.2% (the highest downregulation in this study) with 5 µL/mL of fennel E.O.As for the acOTApks, acOTAnrps, veA and laeA, their reduction levels ranged between 10% and 96% depending on the nature of the E.O and its concentration in the medium.

UHPLC-MS/MS determination of ochratoxin A and fumonisins in coffee using QuEChERS extraction combined with mixed-mode SPE purification.

PubMed

Nielsen, Kristian Fog; Ngemela, Archard Ferdinand; Jensen, Lene Bai; de Medeiros, Lívia Soman; Rasmussen, Peter Have

2015-01-28

A method was developed for simultaneous determination of the mycotoxins: ochratoxin A (OTA) and fumonisins B2 (FB2), B4 (FB4), and B6 (FB6) in green, roasted, and instant coffee. Extraction was performed by QuEChERS (quick, easy, cheap, effective, rugged, and safe) under acidic conditions followed by mixed-mode reversed phase-anion exchange solid phase extraction. OTA and FB2 were detected at levels down to 0.5 and 2 μg/kg by UHPLC-MS/MS and quantitated via isotope dilution using U-(13)C-labeled FB2 and OTA as internal standards. Mixing 20% isopropanol in the acetonitrile of the acidic UHPLC gradient system increased the signal intensity by 50% and decreased the ion-suppression with 50-75% in roasted coffee samples. About half of the roasted coffee samples (n = 57, from 9 countries) contained detectable levels of OTA, however, with only 5 samples above the EU regulatory limit of 5 μg/kg and the highest with 21 μg/kg. None of the 25 instant coffee samples contained OTA above the EU regulatory level of 10 μg/kg. Nonetheless, the toxin could be detected in 56% of the analyzed instant coffee samples. Fumonisins were not detected in any of the roasted or instant coffee samples (n = 82). However, in the green coffee samples (n = 18) almost half of the samples were positive with a maximum value of 164 μg/kg (sum of FB2, FB4, and FB6). This discrepancy between green coffee and processed coffees indicated that the fumonisins decompose during the roasting process, which was confirmed in roasting experiments. Here fumonisins could not be detected after roasting of the green, 164 μg/kg coffee, sample. Under the same conditions, OTA was reduced from 2.4 to 0.5 μg/kg.

Heat shock proteins (Hsp 70) response is not systematic to cell stress: case of the mycotoxin ochratoxin A.

PubMed

Hassen, Wafa; Ayed-Boussema, Imen; Bouslimi, Amel; Bacha, Hassen

2007-12-05

Ochratoxin A (OTA) is a mycotoxin routinely detected in improperly stored animal and human food supplies as well as in human sera worldwide. OTA has multiple toxic effects; however, the most prominent is nephrotoxicity. Thus, OTA is involved in the pathogenesis of human nephropathy in Balkan areas. In this study, we address the question of the appropriate functioning of the basal cellular defense mechanisms, after exposure to OTA, which, up to now, has not been investigated satisfactorily. In this context, we have monitored the effect of OTA on (i) the inhibition of cell viability, (ii) the oxidative damage using the GSH depletion, (iii) the inhibition of protein synthesis through the incorporation of [(3)H] Leucine and (iv) the induction of Hsp 70 gene expression as a parameter of cytotoxicity, oxidative damage and particularly as a protective and adaptative response. This study was conducted using the Human Hep G2 hepatocytes and monkey kidney Vero cells under exposure conditions ranging from non-cytotoxic to sub-lethal. Our results clearly showed that OTA inhibits cell proliferation, strongly reduces protein synthesis and induces the decrease of GSH in concentration-dependent manner in both Hep G2 and Vero cells. However, although cytotoxicity and oxidative damage (main inducers of Hsp expression) occur, no change was observed in Hsp 70 level under the multiple tested conditions. Inhibition of protein synthesis could not explain the absence of Hsp 70 response since concentrations, which did not influence protein synthesis, also failed to display the expected Hsp 70 response. Our data are consistent with recently published reports where considerable differences were noticed in the ability of relevant toxicants to induce Hsp. These results raised doubt about the universal character of Hsp induction which seems to be more complex than originally envisioned. It could be concluded that Hsp 70 induction is not systematic to cell stress.

Effects of different drying treatments on fungal population and ochratoxin A occurrence in sultana type grapes.

PubMed

Şen, Levent; Ocak, İjlal; Nas, Sebahattin; Şevik, Ramazan

2016-09-01

This study aimed to determine the changes in mould and ochratoxin A (OTA) occurrence in sultanas under three different conventional drying conditions. Five different vineyards were chosen, and the three different treatments were applied to these grapes while drying. At the end of the drying process, total mould and black aspergilli (BA) populations in the samples varied from 2.45 to 5.61 log colony-forming units (CFU) g(-)(1) and from 0 to 4.92 log CFU g(-)(1), respectively. Significant increases (p < 0.05) occurred in mould loads depending on the extending drying period. However, independent of vineyard location, all the samples treated with cold dipping solution showed the lowest fungal loads. These results indicate that dipping solution treatment was the most effective drying method to minimise fungal infection of grapes. The expected results could not be achieved by drying grapes artificially contaminated with ochratoxigenic Aspergillus carbonarius spores. Seventy-one of 96 isolates (73.95%) obtained during drying were Aspergillus spp., and the remaining (n = 25, 26.05%) belonged to other genera, such as Penicillium, Trichoderma and Cladosporium. Grape juice-based agar medium was used to determine the realistic OTA production capacities of the isolated mould strains. The highest OTA production capacities were 809.70 ± 9.19, 87.58 ± 16.89 and 45.44 ± 18.78 ng g(-1) in 50% grape juice agar (GJ50), all five of which were from A. niger isolates. OTA was not present in any sample during the drying period; however, OTA was detected in two samples at 0.32 ± 0.15 and 0.52 ± 0.36 µg kg(-)(1) after the end of the drying process. The limit of detection (LOD) and limit of quantitation (LOQ) of the method used for detecting OTA in samples were 0.1 and 0.3 µg kg(-)(1), respectively.

Feeding a diet contaminated with ochratoxin A for chickens at the maximum level recommended by the EU for poultry feeds (0.1 mg/kg). 1. Effects on growth and slaughter performance, haematological and serum traits.

PubMed

Pozzo, L; Salamano, G; Mellia, E; Gennero, M S; Doglione, L; Cavallarin, L; Tarantola, M; Forneris, G; Schiavone, A

2013-05-01

The European Commission Recommendation 2006/576/EC, suggests that the maximum level of Ochratoxin A (OTA) in poultry feeds should be set at 0.1 mg OTA/kg. Thirty-six one-day-old male Hubburd broiler chickens were divided into two groups, a Control (basal diet) and an Ochratoxin A (basal diet + 0.1 mg OTA/kg) group. The growth and slaughter performance traits were recorded. The liver, spleen, bursa of Fabricius and thymus weights were measured. The erythrocyte and leukocyte numbers were assayed in blood samples, and the heterophils to lymphocytes (H/L) ratio was determined. Alpha-1-acid glycoprotein (AGP), lysozyme, the total protein and the electrophoretic pattern were evaluated in serum samples. Liver enzymes (alanino aminotransferase, ALT and aspartate aminotransferase, AST) and kidney function parameters (uric acid and creatinine) were quantified. The results revealed that feeding a 0.1 mg OTA/kg contaminated diet to chicks caused a decrease in the absolute thymus weight (p < 0.05) and a lower total protein (p < 0.01), albumin (p < 0.01), alpha (p < 0.05), beta (p = 0.001) and gamma (p = 0.001) globulins serum concentration in the Ochratoxin A group. Moreover, the albumin-to-globulin (A/G) ratio of the OTA-treated animals resulted to be higher (p < 0.05). Feeding broiler chickens, a diet contaminated with the maximum level admitted by the European Commission Recommendation (0.1 mg OTA/kg), did not affect the animal performance, slaughter traits, organ weights, haematological parameters, liver enzyme or renal function parameters concentrations but had an overall immunosuppressant effect, with reduction in the thymus weight and of the total serum protein, albumin, alpha, beta and gamma globulins concentration. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

Efficacy of natamycin for control of growth and ochratoxin A production by Aspergillus carbonarius strains under different environmental conditions.

PubMed

Medina, A; Jiménez, M; Mateo, R; Magan, N

2007-12-01

To examine the efficacy of natamycin produced by Streptomyces natalensis against strains of Aspergillus carbonarius growth and ochratoxin A (OTA) production under different environmental factors on a grape juice-based medium. Detailed studies in the range 0-20 ng ml(-1) for control of growth and ochratoxin production by strains of A. carbonarius at 0.98, 0.96 and 0.94 water availabilities (a(w)) and 15-25 degrees C on a fresh red grape extract medium were examined. Inhibition of growth was depending on temperature and a(w) level. At 15 degrees C, 5-10 ng ml(-1) natamycin was effective in reducing growth almost completely. However, at 20-25 degrees C and all the three a(w) levels, growth was only slightly inhibited by 5-10 ng ml(-1) natamycin. There were strain differences with regard to inhibition of OTA production. At 15 degrees C and 0.98 a(w), 10 ng ml(-1) was required to inhibit production by >90%. However, at 0.96 and 0.94 a(w), almost complete inhibition occurred. At 20 degrees C, OTA production was only significantly inhibited by 10 ng ml(-1) natamycin at 0.94 a(w). At 0.96 and 0.98 a(w), some inhibition occurred with 5-10 ng ml(-1), but greater concentrations would be required for effective inhibition. At 25 degrees C, 5 ng ml(-1) was effective at all a(w) levels. However, at 15 degrees C and 25 degrees C and a wide range of a(w) levels, natamycin effectively controlled OTA production. Natamycin appears to be a very effective for controlling growth and OTA production by strains of A. carbonarius over a range of a(w) and temperature conditions on grape-based media. This is the first detailed study to demonstrate the impact of natamycin against A. carbonarius. This study suggests that use of natamycin at 50-100 ng ml(-1) can give complete inhibition of growth of A. carbonarius and OTA production over a range of environmental conditions. Natamycin could be an important component of a system to prevent OTA contamination of wine as well during the drying and production of vine fruits.

[Not Available].

PubMed

Hainschitz, I; Rieger, K; Siegl, H

2002-06-01

In Austria an index of 3 μg/kg of Ochratoxin A for coffee, 0,3 μg/kg for fruit juices and 0,2 μg/kg for beer is discussed. The laboratory of the food inspection authority of the state of Vorarlberg investigated the contribution of selected foodstuffs to the daily OTA intake and compared it with the recommendation of the scientific food committee of the EC. The focal point of this study was on beverages (coffee, coffee substitutes, beer and fruit juices) and their ingredients.ZUSAMMENFASSUNG: Die Untersuchungsergebnisse von Bier, Fruchtsaft und Kaffee [Diagramm 1] zeigen, dass die Mehrzahl der Proben nur sehr schwach bis gar nicht belastet waren. Die OTA-Belastung lag bei der Mehrzahl der Proben unter der Nachweisgrenze von 0,3 μg/kg bzw. 0,01μg/1. Einzelne Proben waren aber erheblich belastet, sodass bei starkem Konsum (Fruchtsaft im Sommer) eine überschreitung der vom SCF vorgeschlagenen Höchstmenge nicht auszuschließen ist. Die Ergebnisse der Kaffeemitteluntersuchung [Diagramm 2] belegen eine höhere OTA-Belastung bei mehr als der Hälfte der Proben. Wenn die vom SCF vorgeschlagene Höchstaufnahme von 5 ng pro Tag und kg Körpergewicht zu Grunde gelegt wird, resultiert für eine 60 kg schwere Person ein Wert von 0,3 μg/Tag. Das bedeutet bei einem mit 100 μg/kg OTA kontaminierten Kaffeeersatz und dem Konsum nur einer Tasse (5 - 7 g Pulver), dass alleine aus dieser Quelle diese Höchstaufnahme deutlich überschritten wird. Der Eintrag über die restliche Nahrung wie Cerealien, die für etwa die Hälfte der OTA-Aufnahme verantwortlich sind, bleibt hier unberücksichtigt. Die Untersuchungen belegen, dass die Einhaltung der in österreich vorgeschlagenen Richtwerte bei Bier, Fruchtsäften und Kaffee keine Schwierigkeiten bereitet. Für Kaffeemittel und andere Trockenfrüchte als Weintrauben [3] wurde allerdings noch kein Richtwert vorgeschlagen. Die Ergebnisse belegen aber, dass gerade für Kaffemittel und verschiedene Trockenfrüchte vor dem Hintergrund fehlender Höchstwerte ein Richtwert in der Größenordnung von 3 μg/kg bzw. 10 μg/kg hilfreich wäre, bis die Festlegung der gemeinschaftsrechtlicher Höchstgehalte erfolgt. Mit Hinblick auf die in der Einleitung beschriebene toxische Wirkung von OTA ist es im Sinne eines vorbeugenden Verbraucherschutzes wichtig, diese hochbelasteten Chargen zu erkennen und aus dem Verkehr zu nehmen. Ursache für die OTA-Kontamination ist vor allem eine mangelhafte Produktionshygiene in den Erzeugerländern. Dort liegt auch das größte Potential für eine Verringerung der OTA-Belastung. Die überprüfung der Lebensmittel auf Ochratoxin A durch die amtliche Lebensmittelkontrolle ist ein notwendiger Beitrag zum Schutz der öffentlichen Gesundheit und zur weiteren Reduktion der Aufnahme.

Occurrence of ochratoxin a contamination and detection of ochratoxigenic aspergillus species in retail samples of dried fruits and nuts

USDA-ARS?s Scientific Manuscript database

Ochratoxin A (OTA) is a mycotoxin produced by several species of Aspergillus and Penicillium and is a potential contaminant of a wide variety of food products. To determine the incidence of OTA contamination in dried fruits and tree nuts, retail packaged and bulk raisins, dates, figs, prunes, almon...

Examining the Relationship between Online Travel Agency Information and Traveler Destination Transaction Decisions

ERIC Educational Resources Information Center

Yerby, Dennis

2012-01-01

The purpose of this quantitative study was to examine the role that available Online Travel Agency (OTA) destination information may have on a traveler's perceptions and intent in transaction decisions with that respective OTA. Specifically, this research examined a pleasure traveler's transaction perceptions and intentions with an OTA…

Aptamer-based polyhedral oligomeric silsesquioxane (POSS)-containing hybrid affinity monolith prepared via a "one-pot" process for selective extraction of ochratoxin A.

PubMed

Chen, Yiqiong; Chen, Maolin; Chi, Jinxin; Yu, Xia; Chen, Yongxuan; Lin, Xucong; Xie, Zenghong

2018-08-17

A novel aptamer-based polyhedral oligomeric silsesquioxane (POSS)-containing hybrid affinity monolith has been prepared with a facile "one-pot" process simultaneously via "free radical polymerization" and "thiol-ene" click reaction, and used for on-line selective extraction and practical analysis to trace ochratoxin A (OTA). By using the ternary porogenic mixture composed of water/DMF/PEG, a homogeneous polymerization mixture with POSS chemicals, acrylate-based monomers and aptamer aqueous solution was obtained, and the copolymerization of POSS chemicals, polymer monomers and aptamer aqueous solution was systematically studied. Characterizations such as the morphology, FT-IR and fluorescence spectra, mechanical stability, dynamic binding capacity, cross-reactivity and selectivity of the resultant affinity monolith were also evaluated. Attributed to the porous monolithic structure and aptamer-based affinity interaction, acceptable selective recognition and recovery yields towards trace OTA were obtained. With a 5-fold volume enrichment, the limit of detection (LOD) and limit of quantitation (LOQ) of OTA in fortified beer samples were gained at 0.025 ng/mL (S/N = 3) and 0.045 ng/mL (S/N = 10), respectively. It could be competent for the sensitive measure of actual OTA residues in real beer samples. In comparison with the previously reported strategies containing common "sol-gel" chemistry, the proposed protocol to fabricating aptamer-modified POSS-containing hybrid affinity monolith showed a simpler preparation with acceptable selectivity and higher recovery to trace OTA. Copyright © 2018 Elsevier B.V. All rights reserved.

Development and validation of LC-MS/MS method for the determination of Ochratoxin A and its metabolite Ochratoxin α in poultry tissues and eggs.

PubMed

Paoloni, Angela; Solfrizzo, Michele; Bibi, Rita; Pecorelli, Ivan

2018-05-04

The objective of this study was to develop a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the determination of Ochratoxin A (OTA) and Ochratoxin α (OTα) in poultry tissues and eggs. The two toxins were extracted by a mixture of acetonitrile/water, purified with a reversed phase C18 solid phase extraction column (SPE) and determined by LC-MS/MS. The LC-MS/MS method performances were evaluated in terms of linearity in solvent and in matrix (ranged from 0.5 to 15.10 µg L -1 for OTA and from 0.60 to 17.85 µg L -1 for OTα), limit of detection (LOD), limit of quantitation (LOQ), specificity, accuracy and precision in repeatability conditions. Recovery experiments were performed by spiking poultry liver, kidney, muscle and eggs around 1 µg kg -1 and 10 µg kg -1 . LODs were 0.27 and 0.26 µg kg -1 while LOQs were fixed at 1.0 and 1.2 µg kg -1 for OTA and OTα, respectively. Main recoveries for OTA ranged from 82 to 109% and for OTα ranged from 55 to 89%. The values of within-laboratory relative standard deviation (RSD r ) were equal to or below 20%. Considering the results obtained and that all analytical performance criteria were fulfilled, the new extraction and purification method developed for OTA and OTα determination in animal tissues and eggs was found appropriate for control laboratories and research activities designed to ensure food safety.

Two-dimensional MoS2 as a nano-binder for ssDNA: Ultrasensitive aptamer based amperometric detection of Ochratoxin A.

PubMed

Tang, Juan; Huang, Yapei; Cheng, Yu; Huang, Lulu; Zhuang, Junyang; Tang, Dianping

2018-02-07

Two-dimensional (2D) MoS 2 is found to possess different affinities for ssDNA and dsDNA. This finding is exploited in an amperometric aptamer-based method for the determination of the mycotoxin ochratoxin A (OTA). Initially, a dsDNA probe (formatted through the hybridization of OTA-aptamer with an auxiliary DNA) is self-assembled on a gold electrode. Upon introduction of OTA, it will bind to the aptamer and cause the unwinding of dsDNA, while the auxiliary DNA (with single-stranded structure) remains on the electrode. Since the affinity of 2D MoS 2 for ssDNA is considerably larger than that for dsDNA, it will be adsorbed on the electrode by binding to the auxiliary DNA. Notably, 2D MoS 2 possesses peroxidase-like activity. Hence, it can catalyze the amplification of electrochemical signal of the hydroquinone/benzoquinone redox system. Under optimal conditions, the amperometric signal (best measured at -0.2 V vs. SCE) increases with increasing OTA concentration in the range from 0.5 pg·mL -1 to 1.0 ng·mL -1 , with a lower detection limit of 0.23 pg·mL -1 . The method was applied to the determination of OTA in spiked red wine. Graphical abstract Herein we construct a convenient electrochemical aptasensor for sensitive monitor of ochratoxin A by using 2D MoS 2 as a nano-binder to catalyze the amplification of electrochemical signal from hydroquinone/benzoquinone system.

Aflatoxin and ochratoxin A content of spices in Hungary.

PubMed

Fazekas, B; Tar, A; Kovács, M

2005-09-01

In October and November 2004, 91 spice samples (70 ground red pepper, six black pepper, five white pepper, five spice mix and five chilli samples), the majority of which originated from commercial outlets, were analysed for aflatoxins B1, B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2) and ochratoxin A (OTA) content by high-performance liquid chromatography (HPLC) after immunoaffinity column clean-up. Eighteen of the 70 ground red pepper samples contained AFB1, seven of them in a concentration exceeding the 'maximum level' of 5 microg kg(-1) (range 6.1-15.7 microg kg(-1)). Of the other spices assayed, the AFB1 contamination of one chilli sample exceeded 5 microg kg(-1) (8.1 microg kg(-1)). Thirty-two of the 70 ground red pepper samples contained OTA, eight of them in a concentration exceeding the 10 microg kg(-1) 'maximum level' (range 10.6-66.2 microg kg(-1)). One chilli sample was contaminated with OTA at 2.1 microg kg(-1). The AFB1 and OTA contamination of ground red pepper exceeding the 'maximum level' (5 and 10 microg kg(-1), respectively) was obviously the consequence of mixing imported ground red pepper batches heavily contaminated with AFB1 and OTA with red pepper produced in Hungary. This case calls attention to the importance of consistently screening imported batches of ground red pepper for aflatoxin and ochratoxin A content and strictly prohibiting the use of batches containing mycotoxin concentrations exceeding the maximum permitted level.

The role of bentonite binders in single or concomitant mycotoxin contamination of chicken diets.

PubMed

Pappas, A C; Tsiplakou, E; Tsitsigiannis, D I; Georgiadou, M; Iliadi, M K; Sotirakoglou, K; Zervas, G

2016-08-01

Concomitant presence of mycotoxins is more likely to appear than a single mycotoxicosis since many mycotoxigenic fungi grow and produce their toxic metabolites under similar conditions. The present study was designed to evaluate the efficacy of 4 mycotoxin binders to protect meat-type chickens against single and concomitant administration in the feed of two mycotoxins, namely aflatoxin B1 (AFB1) and ochratoxin A (OTA) both at concentration of 0.1 mg/kg. A total of 440 as hatched, d-old, Ross 308 broilers were reared for 42 d. There were 11 dietary treatments. Chickens were fed on either an uncontaminated basal diet, basal diet and AFB1, basal with concomitant presence of AFB1 and OTA, basal diet and three binders A, B and C (1%) with or without AFB1 or basal diet and binder D (0.5%) with or without concomitant presence of AFB1 and OTA. Performance, carcass yield and several biochemical parameters were examined. Mycotoxin concentration in liver and breast muscle samples was determined. Broiler performance under concomitant mycotoxin contamination was poorer than that under single mycotoxicosis. Mycotoxin presence increased relative heart weight compared to that of broilers fed on uncontaminated diets. Only OTA and not AFB1 was detected and only in the liver. OTA concentration was four-fold lower in broilers fed on a diet with binder compared to those fed on contaminated diets without binder. In conclusion, the study revealed that binder composition and presence or not of multiple toxins may be important factors for optimum broiler performance under mycotoxicosis.

Mycobiota and toxigenic Penicillium species on two Spanish dry-cured ham manufacturing plants.

PubMed

Alapont, C; López-Mendoza, M C; Gil, J V; Martínez-Culebras, P V

2014-01-01

The present study reports the natural mycobiota occurring in dry-cured hams, and in particular on the incidence of mycotoxin-producing fungi. A total of 338 fungal colonies were isolated from three stages of production, these being the post-salting, ripening and aging stages in two manufacturing plants. The results show that fungi were more frequently isolated from the aging stage and that the predominant filamentous fungal genus isolated was Penicillium. Seventy-four of the 338 fungal strains were selected for identification at the species level by using morphological criteria and internal transcribed spacers sequencing. Of the 74 fungal strains, 59 were Penicillium strains. Sixteen Penicillium species were identified, with P. commune (24 strains) and P. chrysogenum (13 strains) being the most abundant. The potential ability to produce cyclopiazonic acid (CPA) and ochratoxin A (OTA) was studied by isolating the culture followed by HPLC analysis of these mycotoxins in the culture extracts. The results indicated that 25 (33.7%) of the 74 fungal strains produced CPA. Worth noting is the high percentage of CPA-producing strains of P. commune (66.6%) of which some strains were highly toxigenic. P. polonicum strains were also highly toxigenic. With respect to OTA-producing fungi, a low percentage of fungal strains (9.5%) were able to produce OTA at moderate levels. OTA-producing fungi belonged to different Penicillium species including P. chrysogenum, P. commune, P. polonicum and P. verrucosum. These results indicate that there is a possible risk factor posed by CPA and OTA contamination of dry-cured hams.

Determination of ochratoxin A in grapes of Greek origin by immunoaffinity and high-performance liquid chromatography.

PubMed

Meletis, Konstantinos; Meniades-Meimaroglou, Sofia; Markaki, Panagiota

2007-11-01

A simple analytical method for ochratoxin A (OTA) determination in grapes is described, using aqueous methanolic extraction, an immunoaffinity column clean-up step and high-performance liquid chromatography with fluorescence detection. Mean recovery was 94% (RSD = 4.0%) with a detection limit of 0.4 ng g(-1) and quantification limit of 1.20 ng g(-1). Repeatability (r) and reproducibility (R) were 1.17 and 1.34, respectively. OTA determinations were applied to 50 grape samples (23 different varieties) originating from representative regions of Greece. Results showed the presence of OTA in 86% of samples tested (n = 50). Traces were found in 56% of samples but OTA was not detectable in 14% of samples. Traces were also found in 4% of red, organically grown samples. The most contaminated were three samples of red grapes, two from Central Greece (2.69 and 1.41 ng g(-1)), both table and wine-making grapes. The third sample (1.46 ng g(-1)), originating from the island of Samos, was used only in wine-making. Mean (1.06 ng g(-1)) and median (0.76 ng g(-1)) OTA concentrations in red grapes were slightly higher compared to the mean (0.82 ng g(-1)) and median (0.65 ng g(-1)) concentrations in white grape samples. The study shows that the potential risk for a person of 60 kg ranged from 0.9 to 9 ng kg(-1) bw day(-1) and is dependent on the quantity of grapes consumed daily.

Molecularly imprinted polymer as sorbent in micro-solid phase extraction of ochratoxin A in coffee, grape juice and urine.

PubMed

Lee, Tien Ping; Saad, Bahruddin; Khayoon, Wejdan Shakir; Salleh, Baharuddin

2012-01-15

A simple, environmental friendly and selective sample preparation technique employing porous membrane protected micro-solid phase extraction (μ-SPE) loaded with molecularly imprinted polymer (MIP) for the determination of ochratoxin A (OTA) is described. After the extraction, the analyte was desorbed using ultrasonication and was analyzed using high performance liquid chromatography. Under the optimized conditions, the detection limits of OTA for coffee, grape juice and urine were 0.06 ng g(-1), 0.02 and 0.02 ng mL(-1), respectively while the quantification limits were 0.19 ng g(-1), 0.06 and 0.08 ng mL(-1), respectively. The recoveries of OTA from coffee spiked at 1, 25 and 50 ng g(-1), grape juice and urine samples at 1, 25 and 50 ng mL(-1) ranged from 90.6 to 101.5%. The proposed method was applied to thirty-eight samples of coffee, grape juice and urine and the presence of OTA was found in eighteen samples. The levels found, however, were all below the legal limits. Copyright © 2011 Elsevier B.V. All rights reserved.

Risk assessment of exposure to aflatoxin B1 and ochratoxin A through consumption of different Pistachio (Pistacia vera L.) cultivars collected from four geographical regions of Iran.

PubMed

Taghizadeh, Seyedeh Faezeh; Rezaee, Ramin; Davarynejad, Gholamhossein; Asili, Javad; Nemati, Seyed Hossein; Goumenou, Marina; Tsakiris, Ioannis; Tsatsakis, Aristides M; Shirani, Kobra; Karimi, Gholamreza

2018-07-01

Iran is one of the main suppliers of pistachio for the European market accounting for over 90% of its demands; hence, efficient analytical methods are required for detection of mycotoxins contamination in pistachio kernels before exporting them. In this study, aflatoxin B1 (AFB1) and ochratoxin A (OTA) levels in five pistachio cultivars collected from four sites of Iran, were measured by HPLC. Based on the results, risk assessment for AFB1 and OTA residues was done. The highest mean concentrations of AFB1 and OTA were found in Ahmad-aghaei (4.33 and 2.19 ng/g, respectively) and Akbari (4.08 and 1.943 ng/g, respectively) cultivars from Rafsanjan, Iran. Even the highest concentrations of AFB1 and OTA in analyzed samples were lower than the corresponding maximum limits set by EU authorities. The hazard index (HI) value for consumers of Iranian pistachio is below one. It could be concluded that consumption of pistachio cultivated in these regions poses no health risk of mycotoxins exposure. Copyright © 2018 Elsevier B.V. All rights reserved.

Estimated Dietary Exposure to Mycotoxins after Taking into Account the Cooking of Staple Foods in Japan

PubMed Central

Sakuma, Hisako; Watanabe, Yasushi; Furusawa, Hiroko; Yoshinari, Tomoya; Akashi, Hajime; Kawakami, Hiroshi; Saito, Shiro; Sugita-Konishi, Yoshiko

2013-01-01

Mycotoxins are commonly present in cereal grains and are not completely destroyed during their cooking and processing. When mycotoxins contaminate staple foods, the risk for exposure becomes serious. In East Asia, including Japan, rice is consumed as a staple food, and with the increasingly Westernized lifestyle, the consumption of wheat has increased. The mycotoxins commonly associated with rice and wheat are total aflatoxin (AFL) and ochratoxin A (OTA), respectively. This study examined the retention of AFL and OTA during the cooking of rice and pasta. AFL was retained at 83%–89% the initial level after the cooking of steamed rice. In pasta noodles, more than 60% of the OTA was retained. These results show that AFL and OTA are relatively stable during the cooking process, suggesting that a major reduction in the exposure to these mycotoxins cannot be expected to occur by cooking rice and pasta. The estimated exposure assessment at the high consumer level (95th percentile) and the mycotoxin contamination level determined by taking into account these reductions in the present study should be useful for the establishment of practical regulations for mycotoxins in staple foods. PMID:23698358

Evaluation of Ochratoxin Recognition by Peptides Using Explicit Solvent Molecular Dynamics

PubMed Central

Thyparambil, Aby A.; Bazin, Ingrid; Guiseppi-Elie, Anthony

2017-01-01

Biosensing platforms based on peptide recognition provide a cost-effective and stable alternative to antibody-based capture and discrimination of ochratoxin-A (OTA) vs. ochratoxin-B (OTB) in monitoring bioassays. Attempts to engineer peptides with improved recognition efficacy require thorough structural and thermodynamic characterization of the binding-competent conformations. Classical molecular dynamics (MD) approaches alone do not provide a thorough assessment of a peptide’s recognition efficacy. In this study, in-solution binding properties of four different peptides, a hexamer (SNLHPK), an octamer (CSIVEDGK), NFO4 (VYMNRKYYKCCK), and a 13-mer (GPAGIDGPAGIRC), which were previously generated for OTA-specific recognition, were evaluated using an advanced MD simulation approach involving accelerated configurational search and predictive modeling. Peptide configurations relevant to ochratoxin binding were initially generated using biased exchange metadynamics and the dynamic properties associated with the in-solution peptide–ochratoxin binding were derived from Markov State Models. Among the various peptides, NFO4 shows superior in-solution OTA sensing and also shows superior selectivity for OTA vs. OTB due to the lower penalty associated with solvating its bound complex. Advanced MD approaches provide structural and energetic insights critical to the hapten-specific recognition to aid the engineering of peptides with better sensing efficacies. PMID:28505090

Rapid all-in-one three-step immunoassay for non-instrumental detection of ochratoxin A in high-coloured herbs and spices.

PubMed

Goryacheva, Irina Yu; De Saeger, Sarah; Nesterenko, Irina S; Eremin, Sergei A; Van Peteghem, Carlos

2007-05-15

A feasible three-step method for ochratoxin A (OTA) rapid detection was developed and applied for OTA screening in high-coloured matrices such as liquorice, ginger, nutmeg, black pepper, white pepper and Capsicum spp. spices at a control level of 10mugkg(-1). The method was based on the clean-up tandem immunoassay column and involved three steps: extract application, washing step and application of chromogenic substrate. A significant simplification of the assay was reached by using an additional frit with conjugate inside the clean-up tandem immunoassay column. The time for analysis was less than 10min, including 5min for colour development. Results were visually evaluated as colour development for negative result or no colour development for positive result. The method was coupled with a simple methanol-based extraction. A total of 27 samples were screened for OTA with the proposed method. It was shown that two samples of red pepper and one sample of liquorice, pili-pili, chilli and cayenne were contaminated with OTA above the control level at 10mugkg(-1), but none of tested ginger, nutmeg, black pepper and white pepper.

Regenerable immuno-biochip for screening ochratoxin A in green coffee extract using an automated microarray chip reader with chemiluminescence detection.

PubMed

Sauceda-Friebe, Jimena C; Karsunke, Xaver Y Z; Vazac, Susanna; Biselli, Scarlett; Niessner, Reinhard; Knopp, Dietmar

2011-03-18

Ochratoxin A (OTA) can contaminate foodstuffs in the ppb to ppm range and once formed, it is difficult to remove. Because of its toxicity and potential risks to human health, the need exists for rapid, efficient detection methods that comply with legal maximum residual limits. In this work we have synthesized an OTA conjugate functionalized with a water-soluble peptide for covalent immobilization on a glass biochip by means of contact spotting. The chip was used for OTA determination with an indirect competitive immunoassay format with flow-through reagent addition and chemiluminescence detection, carried out with the stand-alone automated Munich Chip Reader 3 (MCR 3) platform. A buffer model and real green coffee extracts were used for this purpose. At the present, covalent conjugate immobilization allowed for at least 20 assay-regeneration cycles of the biochip surface. The total analysis time for a single sample, including measurement and surface regeneration, was 12 min and the LOQ of OTA in green coffee extract was 0.3 μg L(-1) which corresponds to 7 μg kg(-1). Copyright © 2011 Elsevier B.V. All rights reserved.

Entry-Level Doctorate for Occupational Therapists: An Assessment of Attitudes of Occupational Therapists and Occupational Therapy Assistants

ERIC Educational Resources Information Center

McCombie, Randy P.

2016-01-01

Purpose: The purpose of this study was to survey occupational therapists (OTs) and occupational therapy assistants (OTAs) on their attitudes toward a possible move to the entry-level doctorate as the mandated singular point of entry into the profession for OTs. Method: The study surveyed a random sample of 600 OTs and 600 OTAs from two…

Assessing interactions of binary mixtures of Penicillium mycotoxins (PMs) by using a bovine macrophage cell line (BoMacs)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oh, Se-Young, E-mail: ohs@uoguelph.ca

Penicillium mycotoxins (PMs) are toxic contaminants commonly found as mixtures in animal feed. Therefore, it is important to investigate potential joint toxicity of PM mixtures. In the present study, we assessed the joint effect of binary combinations of the following PMs: citrinin (CIT), ochratoxin A (OTA), patulin (PAT), mycophenolic acid (MPA) and penicillic acid (PA) using independent action (IA) and concentration addition (CA) concepts. Previously published toxicity data (i.e. IC25; PM concentration that inhibited bovine macrophage (BoMacs) proliferation by 25%) were initially analyzed, and both concepts agreed that OTA + PA demonstrated synergism (p < 0.05), while PAT + PAmore » showed antagonism (p < 0.05). When a follow-up dilution study was carried out using binary combinations of PMs at three different dilution levels (i.e. IC25, 0.5 ∗ IC25, 0.25 ∗ IC25), only the mixture of CIT + OTA at 0.5 ∗ IC25 was determined to have synergism by both IA and CA concepts with Model Deviation Ratios (MDRs; the ratio of predicted versus observed effect concentrations) of 1.4 and 1.7, respectively. The joint effect of OTA + MPA, OTA + PA and CIT + PAT complied with the IA concept, while CIT + PA, PAT + MPA and PAT + PA were better predicted with the CA over the IA concept. The present study suggests to test both IA and CA concepts using multiple doses when assessing risk of mycotoxin mixtures if the mode of action is unknown. In addition, the study showed that the tested PMs could be predicted by IA or CA within an approximate two-fold certainty, raising the possibility for a joint risk assessment of mycotoxins in food and feed. - Highlights: • We investigated the potential joint toxicity of Penicillium mycotoxin (PM) mixtures. • Independent action (IA) and concentration addition (CA) concepts were used. • 7 out of 10 mixtures followed joint toxicity described by IA or CA concepts. • Both concepts agreed that CIT + OTA mixture had synergistic interaction.« less

A fully automated and fast method using direct sample injection combined with fused-core column on-line SPE-HPLC for determination of ochratoxin A and citrinin in lager beers.

PubMed

Lhotská, Ivona; Šatínský, Dalibor; Havlíková, Lucie; Solich, Petr

2016-05-01

A new fast and sensitive method based on on-line solid-phase extraction on a fused-core precolumn coupled to liquid chromatography with fluorescence detection has been developed for ochratoxin A (OTA) and citrinin (CIT) determination in lager beer samples. Direct injection of 100 μL filtered beer samples into an on-line SPE-HPLC system enabled fast and effective sample extraction including separation in less than 6 min. Preconcentration of OTA and CIT from beer samples was performed on an Ascentis Express RP C18 guard column (5 × 4.6 mm), particle size 2.7 μm, with a mobile phase of methanol/0.5% aqueous acetic acid pH 2.8 (30:70, v/v) at a flow rate of 2.0 mL min(-1). The flow switch from extraction column to analytical column in back-flush mode was set at 2.0 min and the separation was performed on the fused-core column Ascentis Express Phenyl-Hexyl (100 × 4.6 mm), particle size 2.7 μm, with a mobile phase acetonitrile/0.5% aqueous acetic acid pH 2.8 in a gradient elution at a flow rate of 1.0 mL min(-1) and temperature of 50 °C. Fluorescence excitation/emission detection wavelengths were set at 335/497 nm. The accuracy of the method, defined as the mean recoveries of OTA and CIT from light and dark beer samples, was in the range 98.3-102.1%. The method showed high sensitivity owing to on-line preconcentration; LOQ values were found to be 10 and 20 ng L(-1) for OTA and CIT, respectively. The found values of OTA and CIT in all tested light, dark and wheat beer samples were significantly below the maximum tolerable limits (3.0 μg kg(-1) for OTA and 2000 μg kg(-1) for CIT) set by the European Union.

Occurrence of Penicillium verrucosum, ochratoxin A, ochratoxin B and citrinin in on-farm stored winter wheat from the Canadian Great Lakes Region

PubMed Central

Miller, J. David; Schaafsma, Arthur W.

2017-01-01

The occurrence of P. verrucosum and ochratoxin A (OTA) were surveyed for 3 and 4 years, respectively. A total of 250 samples was collected from an average of 30 farms during the 2011, 2012, 2013 and 2014 winter seasons. Most storage bins surveyed were typically 11 m high round bins made of corrugated, galvanized steel, with flat-bottoms and conical roofs. Samples of clumped grain contained the most P. verrucosum (p<0.05, n = 10) followed by samples taken from the first load (n = 24, mean = 147±87 CFU/g) and last load (n = 17, mean = 101±77 CFU/g). Five grain samples (2.2%) tested positive for OTA, citrinin and OTB at concentrations of 14.7±7.9, 4.9±1.9 and 1.2±0.7 ng/g, with only three samples exceeding 5 ng/g. Grain samples positive for OTA were related to moisture resulting from either condensation or migrating moist warm air in the bin or areas where precipitation including snow entered the bin. Bins containing grain and clumps contaminated with OTA were studied in detail. A number of statistically-significant risk factors for OTA contamination were identified. These included 1) grain clumps accumulated around or directly under manhole openings, 2) debris and residue of old grain or grain clumps collected from the bin walls or left on storage floor and augers and 3) grain clumps accumulated around side doors. Even when grain enters storage below the 14.5% threshold of moisture, condensation and moisture migration occurs in hotspots in modern corrugated steel storage bins. Hot spots of OTA contamination were most often in areas affected by moisture migration due to inadequate aeration and exposure to moisture from precipitation or condensation. Further, we found that the nature of the condensation affects the nature and distribution of small and isolated areas with high incidence of toxin contamination and/or P. verrucosum prevalence in the grain bins examined. PMID:28749978

Occurrence of Penicillium verrucosum, ochratoxin A, ochratoxin B and citrinin in on-farm stored winter wheat from the Canadian Great Lakes Region.

PubMed

Limay-Rios, Victor; Miller, J David; Schaafsma, Arthur W

2017-01-01

The occurrence of P. verrucosum and ochratoxin A (OTA) were surveyed for 3 and 4 years, respectively. A total of 250 samples was collected from an average of 30 farms during the 2011, 2012, 2013 and 2014 winter seasons. Most storage bins surveyed were typically 11 m high round bins made of corrugated, galvanized steel, with flat-bottoms and conical roofs. Samples of clumped grain contained the most P. verrucosum (p<0.05, n = 10) followed by samples taken from the first load (n = 24, mean = 147±87 CFU/g) and last load (n = 17, mean = 101±77 CFU/g). Five grain samples (2.2%) tested positive for OTA, citrinin and OTB at concentrations of 14.7±7.9, 4.9±1.9 and 1.2±0.7 ng/g, with only three samples exceeding 5 ng/g. Grain samples positive for OTA were related to moisture resulting from either condensation or migrating moist warm air in the bin or areas where precipitation including snow entered the bin. Bins containing grain and clumps contaminated with OTA were studied in detail. A number of statistically-significant risk factors for OTA contamination were identified. These included 1) grain clumps accumulated around or directly under manhole openings, 2) debris and residue of old grain or grain clumps collected from the bin walls or left on storage floor and augers and 3) grain clumps accumulated around side doors. Even when grain enters storage below the 14.5% threshold of moisture, condensation and moisture migration occurs in hotspots in modern corrugated steel storage bins. Hot spots of OTA contamination were most often in areas affected by moisture migration due to inadequate aeration and exposure to moisture from precipitation or condensation. Further, we found that the nature of the condensation affects the nature and distribution of small and isolated areas with high incidence of toxin contamination and/or P. verrucosum prevalence in the grain bins examined.

Tissue distribution and elimination of deoxynivalenol and ochratoxin A in dietary-exposed Atlantic salmon (Salmo salar).

PubMed

Bernhoft, Aksel; Høgåsen, Helga R; Rosenlund, Grethe; Ivanova, Lada; Berntssen, Marc H G; Alexander, Jan; Eriksen, Gunnar Sundstøl; Fæste, Christiane Kruse

2017-07-01

Post-smolt Atlantic salmon (Salmo salar) were fed standard feed with added 2 or 6 mg kg -1 pure deoxynivalenol (DON), 0.8 or 2.4 mg kg -1 pure ochratoxin A (OTA), or no added toxins for up to 8 weeks. The experiments were performed in duplicate tanks with 25 fish each per diet group, and the feed was given for three 2-h periods per day. After 3, 6 and 8 weeks, 10 fish from each diet group were sampled. In the following hours after the last feeding at 8 weeks, toxin elimination was studied by sampling three fish per diet group at five time points. Analysis of DON and OTA in fish tissues and plasma was conducted by liquid chromatography-mass spectrometry and high-pressure liquid chromatography with fluorescence detection, respectively. DON was distributed to the liver, kidney, plasma, muscle, skin and brain, and the concentrations in liver and muscle increased significantly from 3 to 8 weeks of exposure to the high-DON diet. After the last feeding at 8 weeks, DON concentration in liver reached a maximum at 1 h and decreased thereafter with a half-life (t 1/2 ) of 6.2 h. DON concentration in muscle reached a maximum at 6 h and was then eliminated with a t 1/2  = 16.5 h. OTA was mainly found in liver and kidney, and the concentration in liver decreased significantly from 3 to 8 weeks in the high-OTA group. OTA was eliminated faster than DON from various tissues. By using Norwegian food consumption data and kinetic findings in this study, we predicted the human exposure to DON and OTA from fish products through carryover from the feed. Following a comparison with tolerable daily intakes, we found the risk to human health from the consumption of salmon-fed diets containing maximum recommended levels of these toxins to be negligible.

Quantitative determination of mycotoxins in urine by LC-MS/MS.

PubMed

Ahn, J; Kim, D; Kim, H; Jahng, K-Y

2010-12-01

Naturally occurring mycotoxins are responsible for a wide array of adverse health effects. The measurement of urinary mycotoxin levels is a useful means of assessing an individual's exposure, but the development of sensitive and accurate analytical methods for detecting mycotoxins and their metabolites in urine samples is challenging. Urinary mycotoxins are present in low pg ml⁻¹ concentrations, and the chromatographic identification of their metabolites can be obscured by other endogenous metabolites. We developed an analytical method focused on the selection of two appropriate multiple-reaction monitoring transition for unambiguous identification and quantification of carcinogenic aflatoxin M₁ (AFM₁), ochratoxin A (OTA) and fumonisin B₁, B₂ (FB₁, FB₂) in urine samples from a small volunteer group in a pilot study. AFM₁, OTA, FB₁ and FB₂ were concentrated selectively, interfering substances were removed using an immunoaffinity column (IAC), and mycotoxins were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in combination with a stable-isotope standard-dilution assay (SIDA). The method was sensitive enough to measure mycotoxins and their metabolites at pg ml⁻¹ levels in urine. The combination of LC-MS/MS and SIDA was critical to distinguishing pseudo-OTα interference from genuine OTα. Twelve urine samples contained OTA ranging from 0.013 to 0.093 ng ml⁻¹ (mean = 0.031 ng ml⁻¹). AFM₁ were detected in one sample at a 0.002 ng ml⁻¹ level, while FB₁ and FB₂ were undetectable in all 12 samples. None of the samples in this pilot study contained a detectable level of OTα, despite the presence of OTA, and this may suggest the need for further epidemiological investigation of OTA exposure in the Korean population.

Improved sensitivity of ochratoxin A analysis in coffee using high-performance liquid chromatography with hybrid triple quadrupole-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS).

PubMed

Kokina, Aija; Pugajeva, Iveta; Bartkevics, Vadims

2016-01-01

A novel and sensitive method utilising high-performance liquid chromatography coupled to triple quadrupole-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS) was developed in order to analyse the content of ochratoxin A (OTA) in coffee samples. The introduction of the triple-stage MS scanning mode (MS(3)) has been shown to increase greatly sensitivity and selectivity by eliminating the high chromatographic baseline caused by interference of complex coffee matrices. The analysis included the sample preparation procedure involving extraction of OTA using a methanol-water mixture and clean-up by immunoaffinity columns and detection using the MS(3) scanning mode of LC-QqQLIT-MS/MS. The proposed method offered a good linear correlation (r(2) > 0.998), excellent precision (RSD < 2.9%) and recovery (94%). The limit of quantification (LOQ) for coffee beans and espresso beverages was 0.010 and 0.003 µg kg(-1), respectively. The developed procedure was compared with traditional methods employing liquid chromatography coupled to fluorescent and tandem quadrupole detectors in conjunction with QuEChERS and solid-phase extraction. The proposed method was successfully applied to the determination of OTA in 15 samples of coffee beans and in 15 samples of espresso coffee beverages obtained from the Latvian market. OTA was found in 10 samples of coffee beans and in two samples of espresso in the ranges of 0.018-1.80 µg kg(-1) and 0.020-0.440 µg l(-1), respectively. No samples exceeded the maximum permitted level of OTA in the European Union (5.0 µg kg(-1)).

Carcinogens induce loss of the primary cilium in human renal proximal tubular epithelial cells independently of effects on the cell cycle

PubMed Central

Radford, Robert; Slattery, Craig; Jennings, Paul; Blacque, Oliver; Pfaller, Walter; Gmuender, Hans; Van Delft, Joost; Ryan, Michael P.

2012-01-01

The primary cilium is an immotile sensory and signaling organelle found on the majority of mammalian cell types. Of the multitude of roles that the primary cilium performs, perhaps some of the most important include maintenance of differentiation, quiescence, and cellular polarity. Given that the progression of cancer requires disruption of all of these processes, we have investigated the effects of several carcinogens on the primary cilium of the RPTEC/TERT1 human proximal tubular epithelial cell line. Using both scanning electron microscopy and immunofluorescent labeling of the ciliary markers acetylated tubulin and Arl13b, we confirmed that RPTEC/TERT1 cells express primary cilium upon reaching confluence. Treatment with the carcinogens ochratoxin A (OTA) and potassium bromate (KBrO3) caused a significant reduction in the number of ciliated cells, while exposure to nifedipine, a noncarcinogenic renal toxin, had no effect on primary cilium expression. Flow cytometric analysis of the effects of all three compounds on the cell cycle revealed that only KBrO3 resulted in an increase in the proportion of cells entering the cell cycle. Microarray analysis revealed dysregulation of multiple pathways affecting ciliogenesis and ciliary maintenance following OTA and KBrO3 exposure, which were unaffected by nifedipine exposure. The primary cilium represents a unique physical checkpoint with relevance to carcinogenesis. We have shown that the renal carcinogens OTA and KBrO3 cause significant deciliation in a model of the proximal tubule. With KBrO3, this was followed by reentry into the cell cycle; however, deciliation was not found to be associated with reentry into the cell cycle following OTA exposure. Transcriptomic analysis identified dysregulation of Wnt signaling and ciliary trafficking in response to OTA and KBrO3 exposure. PMID:22262483

pODI at WIYN: Instrument Performance and Upgrade Path

NASA Astrophysics Data System (ADS)

Harbeck, Daniel R.; Boroson, T. A.; Rajagopal, J.; ODI Team; PPA Team

2013-06-01

A preliminary version of the WIYN One Degree Imager (ODI) has been commissioned throughout the semester 2012B, and has been put into scientific operation February 2013. ODI was devised to take advantage of the excellent image quality and wide field of view of the WIYN 3.5m telescope. To further improve delivered image quality, ODI uses Orthogonal Transfer Array (OTA) detectors that have the capability to electronically correct for image motion in the detectors during an exposure. The partial ODI (pODI) populates 13 out of the 64 OTAs in the focal plane, and coherent image motion correction is enabled. The 13 OTAs are configured as a 24 x 24 arcminute central “science field”, plus 4 outer OTAs, allowing the sampling of all radii within the one square degree field. Guide star signals from the outer detectors are either directed to the telescope only, or additionally used to calculate a global, coherent shift correction that is sent to the OTAs. The performance of pODI is excellent. Image quality is site seeing limited, and, on good seeing nights, we can achieve images around 0.4 arcsec FWHM over the entire field. We are still in the process of characterizing the gains from active image motion correction, but the detectors perform well in this mode. Data are immediately transferred to an archive at Indiana University, where they are pipeline-processed to remove instrumental signature. In this poster we summarize the current performance of the pODI instrument and outline a path towards a future, expanded version of ODI with a 6x6 central detector array, or a field of view of 48 x 48 arcminutes.

The effects of heavy metal ions, phthalates and ochratoxin A on oxidation of carcinogenic aristolochic acid I causing Balkan endemic nephropathy.

PubMed

Barta, Frantisek; Levova, Katerina; Hodek, Petr; Schmeiser, Heinz H; Arlt, Volker M; Stiborova, Marie

2015-01-01

Balkan endemic nephropathy (BEN) is a chronic progressive fibrosis associated with upper urothelial carcinoma (UUC). Aetiology of BEN is still not fully explained. Although carcinogenic aristolochic acid I (AAI) was proven as the major cause of BEN/UUC, this nephropathy is considered to be multifactorial. Hence, we investigated whether other factors considered as potential causes of BEN [a mycotoxin ochratoxin A (OTA), Cd, Pb, Se and As ions and organic compounds (i.e. phthalates) released from lignite deposits in BEN areas] can influence detoxication of AAI, whose concentrations are crucial for BEN development. Oxidation of AAI to 8-hydroxyaristolochic acid I (AAIa) in the presence of Cd, Pb, Se, As ions, dibutylphthalate (DBP), butylbenzylphthalate (BBP), bis(2-ethylhexyl)phthalate (DEHP) and OTA by rat liver microsomes was determined by HPLC. Only OTA, cadmium and selenium ions, and BBP inhibited AAI oxidation by rat liver microsomes. These compounds also inhibited activities of CYP1A1 and/or CYP2C6/11 catalysing AAI demethylation in rat livers. Therefore, these CYP inhibitions can be responsible for a decrease in AAIa formation. When the combined effects of these compounds were investigated, the most efficient inhibition was caused by OTA combined with BBP and selenium ions. The results show low effects of BBP, cadmium and selenium ions, and/or their combinations on AAI detoxication. No effects were produced by the other metal ions (Pb, As) and phthalates DBP and DEHP. This finding suggests that they do not influence AAI-mediated BEN development. In contrast, OTA might influence this process, by inhibition of AAI detoxication.

Occurrence and biodiversity of Aspergillus section Nigri on 'Tannat' grapes in Uruguay.

PubMed

Garmendia, Gabriela; Vero, Silvana

2016-01-04

Ochratoxin A (OTA) is a nephrotoxic mycotoxin which has been found worldwide as a contaminant in wines. It is produced on grapes mainly by molds from Aspergillus section Nigri. This study has demonstrated for the first time the occurrence of black aspergilli on Tannat grapes from Uruguay, in a two year survey. Aspergillus uvarum (uniseriate) and Aspergillus welwitschiae (from Aspergillusniger aggregate) were the prevalent species whereas Aspergillus carbonarius which is considered the main OTA producing species was not detected. OTA production in culture medium was evaluated for native isolates from A. niger aggregate and compared to levels produced by a type strain of A. carbonarius. This work also includes the development of quick and easy molecular methods to identify black aspergilli to species level, avoiding sequencing. Copyright © 2015 Elsevier B.V. All rights reserved.

Extreme lightweight ZERODUR mirrors (ELZM): supporting characteristics for spaceborne applications

NASA Astrophysics Data System (ADS)

Hull, Tony; Westerhoff, Thomas

2014-08-01

Extreme Lightweight ZERODUR® Mirrors (ELZM) have been developed expressly to provide architects of spaceborne missions a new, cost-effective, option for implementation of medium and large Optical Telescope Assemblies (OTAs, up to 4+ meters in diameter). ZERODUR® is a traditional material in space with over a 30 year heritage. We will discuss the attributes of the material and fabrication methods to aggressively reduce weight to an extent now routinely available. Recent and emerging independent measurements of material properties will confirm the utility of this approach for new generations of OTAs. Data on dimensional stability over a broad practical temperature range will be referenced, as will recent mechanical strength data. Other data confirming suitability for use in space will be referenced. We will discuss how this data can be used for the architecture of a ELZM based cost-effective spaceborne OTA.

Cost Modeling for Space Telescope

NASA Technical Reports Server (NTRS)

Stahl, H. Philip

2011-01-01

Parametric cost models are an important tool for planning missions, compare concepts and justify technology investments. This paper presents on-going efforts to develop single variable and multi-variable cost models for space telescope optical telescope assembly (OTA). These models are based on data collected from historical space telescope missions. Standard statistical methods are used to derive CERs for OTA cost versus aperture diameter and mass. The results are compared with previously published models.

Measuring Stability and Security in Iraq

DTIC Science & Technology

2008-09-01

The Office of the Transportation Attaché (OTA) is helping the Iraqi Ministry of Construction and Housing ( MoCH ) promote economic prosperity...through expansion of highway transport to strengthen Iraq’s links to the global economy and to provide mobility to Iraqi citizens. The MoCH and the OTA...work closely in setting national transport priorities, defining where the MoCH must focus in the short term, and identifying specific strategic

Changes in ochratoxin A and type B trichothecenes contained in wheat flour during dough fermentation and bread-baking.

PubMed

Valle-Algarra, F M; Mateo, E M; Medina, A; Mateo, F; Gimeno-Adelantado, J V; Jimenez, M

2009-06-01

Ochratoxin A (OTA) and type B trichothecenes are mycotoxins that occur frequently in cereals and thus can be found in cereal by-products such as bread. The aim of this work was to study the variation of the levels of OTA, deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON) and nivalenol (NIV) during the bread-making process. This was done by using wheat flour spiked with different levels of toxins. Mycotoxin levels were controlled after fermentation of the dough with yeasts (Saccharomyces cerevisiae) and after further baking at different temperature-time combinations. Analysis of variance (ANOVA) of the results showed a significant reduction in OTA level (p < 0.05) during fermentation of the dough. The reduction ranged between 29.8% and 33.5%, depending on the initial concentration of toxin in the flour. During this period, the level of the other mycotoxins studied was not modified. By contrast, in the baking phase there were significant changes in the levels of the four mycotoxins, although the reduction was similar under all the baking conditions. Considering all the temperature-time conditions tested, it can be concluded that during the baking period the average reduction of OTA, NIV, 3-ADON, and DON was 32.9%, 76.9%, 65.6%, and 47.9%, respectively.

Determination of Ochratoxin A in Rye and Rye-Based Products by Fluorescence Polarization Immunoassay

PubMed Central

Lippolis, Vincenzo; Porricelli, Anna C. R.; Cortese, Marina; Zanardi, Sandro; Pascale, Michelangelo

2017-01-01

A rapid fluorescence polarization immunoassay (FPIA) was optimized and validated for the determination of ochratoxin A (OTA) in rye and rye crispbread. Samples were extracted with a mixture of acetonitrile/water (60:40, v/v) and purified by SPE-aminopropyl column clean-up before performing the FPIA. Overall mean recoveries were 86 and 95% for spiked rye and rye crispbread with relative standard deviations lower than 6%. Limits of detection (LOD) of the optimized FPIA was 0.6 μg/kg for rye and rye crispbread, respectively. Good correlations (r > 0.977) were observed between OTA contents in contaminated samples obtained by FPIA and high-performance liquid chromatography (HPLC) with immunoaffinity cleanup used as reference method. Furthermore, single laboratory validation and small-scale collaborative trials were carried out for the determination of OTA in rye according to Regulation 519/2014/EU laying down procedures for the validation of screening methods. The precision profile of the method, cut-off level and rate of false suspect results confirm the satisfactory analytical performances of assay as a screening method. These findings show that the optimized FPIA is suitable for high-throughput screening, and permits reliable quantitative determination of OTA in rye and rye crispbread at levels that fall below the EU regulatory limits. PMID:28954398

Nuclear Safeguards and the International Atomic Energy Agency

DTIC Science & Technology

1995-04-01

1993; Export Controls and Nonprolife ration Policy, OTA-ISS-596, May 1994; and Proliferation and the Former Soviet Union, OTA-ISC-605, September 1994...states would likely be much less reprocessing plant such as that being built by sanguine about the effectiveness of safeguards if a Japan at Rokkasho... formulate more intelligent and constructive pro- criminal record or are otherwise not eligible to en- posals for its improvement, which could ultimate- ter

Faster, Better, Cheaper: A ZERODUR® low-expansion, light-weight present path toward affordable spaceborne telescopes

NASA Astrophysics Data System (ADS)

Hull, Anthony B.; Westerhoff, Thomas

2014-06-01

For competed missions, payload costs are often the discriminate of whether or not outstanding science can be selected to fly. Optical Telescope Assemblies (OTAs) encompass a significant fraction of the payload cost, and mirror aperture and stability are usually are key to the science merit. The selection of the primary mirror approach drives architecture decisions for the rest of the OTA and even payload. We look at the ways OTA architecture is affected by the PM selection, and specifically at the benefits of selecting a low expansion material. We will also review recent advances in ZERODUR® fabrication which make this low-expansion material relevant in situations where affordable, lightweight mirrors can enable the apertures needed for science merit. Extreme Lightweight ZERODUR® Mirrors (ELZM) are available in apertures from 0.3m to over 4m. SCHOTT has recently demonstrated a relevant 1.2m ELZM substrate.

Rapid prediction of ochratoxin A-producing strains of Penicillium on dry-cured meat by MOS-based electronic nose.

PubMed

Lippolis, Vincenzo; Ferrara, Massimo; Cervellieri, Salvatore; Damascelli, Anna; Epifani, Filomena; Pascale, Michelangelo; Perrone, Giancarlo

2016-02-02

The availability of rapid diagnostic methods for monitoring ochratoxigenic species during the seasoning processes for dry-cured meats is crucial and constitutes a key stage in order to prevent the risk of ochratoxin A (OTA) contamination. A rapid, easy-to-perform and non-invasive method using an electronic nose (e-nose) based on metal oxide semiconductors (MOS) was developed to discriminate dry-cured meat samples in two classes based on the fungal contamination: class P (samples contaminated by OTA-producing Penicillium strains) and class NP (samples contaminated by OTA non-producing Penicillium strains). Two OTA-producing strains of Penicillium nordicum and two OTA non-producing strains of Penicillium nalgiovense and Penicillium salamii, were tested. The feasibility of this approach was initially evaluated by e-nose analysis of 480 samples of both Yeast extract sucrose (YES) and meat-based agar media inoculated with the tested Penicillium strains and incubated up to 14 days. The high recognition percentages (higher than 82%) obtained by Discriminant Function Analysis (DFA), either in calibration and cross-validation (leave-more-out approach), for both YES and meat-based samples demonstrated the validity of the used approach. The e-nose method was subsequently developed and validated for the analysis of dry-cured meat samples. A total of 240 e-nose analyses were carried out using inoculated sausages, seasoned by a laboratory-scale process and sampled at 5, 7, 10 and 14 days. DFA provided calibration models that permitted discrimination of dry-cured meat samples after only 5 days of seasoning with mean recognition percentages in calibration and cross-validation of 98 and 88%, respectively. A further validation of the developed e-nose method was performed using 60 dry-cured meat samples produced by an industrial-scale seasoning process showing a total recognition percentage of 73%. The pattern of volatile compounds of dry-cured meat samples was identified and characterized by a developed HS-SPME/GC-MS method. Seven volatile compounds (2-methyl-1-butanol, octane, 1R-α-pinene, d-limonene, undecane, tetradecanal, 9-(Z)-octadecenoic acid methyl ester) allowed discrimination between dry-cured meat samples of classes P and NP. These results demonstrate that MOS-based electronic nose can be a useful tool for a rapid screening in preventing OTA contamination in the cured meat supply chain. Copyright © 2015 Elsevier B.V. All rights reserved.

Sequencing and functional annotation of the whole genome of the filamentous fungus Aspergillus westerdijkiae.

PubMed

Han, Xiaolong; Chakrabortti, Alolika; Zhu, Jindong; Liang, Zhao-Xun; Li, Jinming

2016-08-15

Aspergillus westerdijkiae produces ochratoxin A (OTA) in Aspergillus section Circumdati. It is responsible for the contamination of agricultural crops, fruits, and food commodities, as its secondary metabolite OTA poses a potential threat to animals and humans. As a member of the filamentous fungi family, its capacity for enzymatic catalysis and secondary metabolite production is valuable in industrial production and medicine. To understand the genetic factors underlying its pathogenicity, enzymatic degradation, and secondary metabolism, we analysed the whole genome of A. westerdijkiae and compared it with eight other sequenced Aspergillus species. We sequenced the complete genome of A. westerdijkiae and assembled approximately 36 Mb of its genomic DNA, in which we identified 10,861 putative protein-coding genes. We constructed a phylogenetic tree of A. westerdijkiae and eight other sequenced Aspergillus species and found that the sister group of A. westerdijkiae was the A. oryzae - A. flavus clade. By searching the associated databases, we identified 716 cytochrome P450 enzymes, 633 carbohydrate-active enzymes, and 377 proteases. By combining comparative analysis with Kyoto Encyclopaedia of Genes and Genomes (KEGG), Conserved Domains Database (CDD), and Pfam annotations, we predicted 228 potential carbohydrate-active enzymes related to plant polysaccharide degradation (PPD). We found a large number of secondary biosynthetic gene clusters, which suggested that A. westerdijkiae had a remarkable capacity to produce secondary metabolites. Furthermore, we obtained two more reliable and integrated gene sequences containing the reported portions of OTA biosynthesis and identified their respective secondary metabolite clusters. We also systematically annotated these two hybrid t1pks-nrps gene clusters involved in OTA biosynthesis. These two clusters were separate in the genome, and one of them encoded a couple of GH3 and AA3 enzyme genes involved in sucrose and glucose metabolism. The genomic information obtained in this study is valuable for understanding the life cycle and pathogenicity of A. westerdijkiae. We identified numerous enzyme genes that are potentially involved in host invasion and pathogenicity, and we provided a preliminary prediction for each putative secondary metabolite (SM) gene cluster. In particular, for the OTA-related SM gene clusters, we delivered their components with domain and pathway annotations. This study sets the stage for experimental verification of the biosynthetic and regulatory mechanisms of OTA and for the discovery of new secondary metabolites.

Mycobiota and Mycotoxins in Traditional Medicinal Seeds from China

PubMed Central

Chen, Amanda Juan; Jiao, Xiaolin; Hu, Yongjian; Lu, Xiaohong; Gao, Weiwei

2015-01-01

The multi-mycotoxin occurrence for internal and superficial fungi contamination were comprehensively assessed in medicinal seeds used as food or beverage. Based on a polyphasic approach using morphological characters, β-tubulin and ITS gene blast, a total of 27 species belonging to 12 genera were identified from surface-sterilized seeds. Chaetomium globosporum was most predominant (23%), followed by Microascus trigonosporus (12%) and Alternaria alternata (9%). With respect to superficial mycobiota, thirty-four species belonging to 17 genera were detected. Aspergillus niger and Penicillium polonicum were predominant (12% and 15%, respectively). Medicinal seed samples and potential toxigenic fungi were tested for ochratoxin A (OTA) and aflatoxins (AFB1, AFB2, AFG1, AFG2) using UPLC-MS/MS. Platycladi seeds were contaminated with AFB1 (52.0 µg/kg) and tangerine seed was contaminated with OTA (92.3 µg/kg). Subsequent analysis indicated that one A. flavus strain isolated from platycladi seed was able to synthesize AFB1 (102.0 µg/kg) and AFB2 (15.3 µg/kg). Two P. polonicum strains isolated from tangerine and lychee seeds were able to synthesize OTA (4.1 µg/kg and 14.8 µg/kg, respectively). These results identify potential sources of OTA and aflatoxins in medicinal seeds and allude to the need to establish permitted limits for these mycotoxins in these seeds that are commonly consumed by humans. PMID:26404373

Mycobiota and Mycotoxins in Traditional Medicinal Seeds from China.

PubMed

Chen, Amanda Juan; Jiao, Xiaolin; Hu, Yongjian; Lu, Xiaohong; Gao, Weiwei

2015-09-24

The multi-mycotoxin occurrence for internal and superficial fungi contamination were comprehensively assessed in medicinal seeds used as food or beverage. Based on a polyphasic approach using morphological characters, β-tubulin and ITS gene blast, a total of 27 species belonging to 12 genera were identified from surface-sterilized seeds. Chaetomium globosporum was most predominant (23%), followed by Microascus trigonosporus (12%) and Alternaria alternata (9%). With respect to superficial mycobiota, thirty-four species belonging to 17 genera were detected. Aspergillus niger and Penicillium polonicum were predominant (12% and 15%, respectively). Medicinal seed samples and potential toxigenic fungi were tested for ochratoxin A (OTA) and aflatoxins (AFB1, AFB2, AFG1, AFG2) using UPLC-MS/MS. Platycladi seeds were contaminated with AFB1 (52.0 µg/kg) and tangerine seed was contaminated with OTA (92.3 µg/kg). Subsequent analysis indicated that one A. flavus strain isolated from platycladi seed was able to synthesize AFB1 (102.0 µg/kg) and AFB2 (15.3 µg/kg). Two P. polonicum strains isolated from tangerine and lychee seeds were able to synthesize OTA (4.1 µg/kg and 14.8 µg/kg, respectively). These results identify potential sources of OTA and aflatoxins in medicinal seeds and allude to the need to establish permitted limits for these mycotoxins in these seeds that are commonly consumed by humans.

Oral Tranexamic Acid Reduces Transfusions in Total Knee Arthroplasty.

PubMed

Perreault, Roger E; Fournier, Christine A; Mattingly, David A; Junghans, Richard P; Talmo, Carl T

2017-10-01

Tranexamic acid (TXA) reduces intraoperative blood loss and transfusions in patients undergoing total knee arthroplasty. Although numerous studies demonstrate the efficacy of intravenous and topical TXA in these patients, few demonstrate the effectiveness and appropriate dosing recommendations of oral formulations. A retrospective cohort study was performed to evaluate differences in transfusion requirements in patients undergoing primary unilateral total knee arthroplasty with either no TXA (n = 866), a single-dose of oral TXA (n = 157), or both preoperative and postoperative oral TXA (n = 1049). Secondary outcomes included postoperative hemoglobin drop, total units transfused, length of stay, drain output, and cell salvage volume. Transfusion rates decreased from 15.4% in the no-oral tranexamic acid (OTA) group to 9.6% in the single-dose OTA group (P < .001) and 7% in the 2-dose group (P < .001), with no difference in transfusion rates between the single- and 2-dose groups (P = .390). In addition, postoperative hemoglobin drop was reduced from 4.2 g/dL in the no-OTA group to 3.5 g/dL in the single-dose group (P < .01) and to 3.4 g/dL in the 2-dose group (P < .01), without a difference between the single- and 2-dose groups (P = .233). OTA reduces transfusions, with greater ease of administration and improved cost-effectiveness relative to other forms of delivery. Copyright © 2017 Elsevier Inc. All rights reserved.

LAMP-PCR detection of ochratoxigenic Aspergillus species collected from peanut kernel.

PubMed

Al-Sheikh, H M

2015-01-30

Over the last decade, ochratoxin A (OTA) has been widely described and is ubiquitous in several agricultural products. Ochratoxins represent the second-most important mycotoxin group after aflatoxins. A total of 34 samples were surveyed from 3 locations, including Mecca, Madina, and Riyadh, Saudi Arabia, during 2012. Fungal contamination frequency was determined for surface-sterilized peanut seeds, which were seeded onto malt extract agar media. Aspergillus niger (35%), Aspergillus ochraceus (30%), and Aspergillus carbonarius (25%) were the most frequently observed Aspergillius species, while Aspergillus flavus and Aspergillus phoenicis isolates were only infrequently recovered and in small numbers (10%). OTA production was evaluated on yeast extract sucrose medium, which revealed that 57% of the isolates were A. niger and 60% of A. carbonarius isolates were OTA producers; 100% belonged to A. ochraceus. Only one isolate, morphologically identified as A. carbonarius, and 3 A. niger isolates unstably produced OTA. A polymerase chain reaction (PCR)-based identification and detection assay was used to identify A. ochraceus isolates. Using the primer sets OCRA1/OCRA2, 400-base pair PCR fragments were produced only when genomic DNA from A. ochraceus isolates was used. Recently, the loop-mediated isothermal amplification assay using recombinase polymerase amplification chemistry was used for A. carbonarius and A. niger DNA identification. As a non-gel-based technique, the amplification product was directly visualized in the reaction tube after adding calcein for naked-eye examination.

Simultaneous multi-mycotoxin determination in nutmeg by ultrasound-assisted solid-liquid extraction and immunoaffinity column clean-up coupled with liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection.

PubMed

Kong, Wei-Jun; Liu, Shu-Yu; Qiu, Feng; Xiao, Xiao-He; Yang, Mei-Hua

2013-05-07

A simple and sensitive analytical method based on ultrasound-assisted solid-liquid extraction and immunoaffinity column clean-up coupled with high performance liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection (USLE-IAC-HPLC-PCD-FLD) has been developed for simultaneous multi-mycotoxin determination of aflatoxins B1, B2, G1, G2 (AFB1, AFB2, AFG1, AFG2) and ochratoxin A (OTA) in 13 edible and medicinal nutmeg samples marketed in China. AFs and OTA were extracted from nutmeg samples by ultrasonication using a methanol : water (80 : 20, v/v) solution, followed by an IAC clean-up step. Different USL extraction conditions, pre-processing ways for nutmeg sample and clean-up columns for mycotoxins, as well as HPLC-PCD-FLD parameters (mobile phase, column temperature, elution procedure, excitation and emission wavelengths) were optimized. This method, which was appraised for analyzing nutmeg samples, showed satisfactory results with reference to limits of detection (LODs) (from 0.02 to 0.25 μg kg(-1)), limits of quantification (LOQs) (from 0.06 to 0.8 μg kg(-1)), linear ranges (up to 30 ng mL(-1) for AFB1, AFG1 and OTA and 9 ng mL(-1) for AFB2 and AFG2), intra- and inter-day variability (all <2%) and average recoveries (from 79.6 to 90.8% for AFs and from 93.6 to 97.3% for OTA, respectively). The results of the application of developed method in nutmeg samples have elucidated that four samples were detected with contamination of AFs and one with OTA. AFB1 was the most frequently found mycotoxin in 30.8% of nutmeg samples at contamination levels of 0.73-16.31 μg kg(-1). At least two different mycotoxins were co-occurred in three samples, and three AFs were simultaneously detected in one sample.

Natural occurrence of aflatoxins and ochratoxin A in processed spices marketed in Malaysia.

PubMed

Ali, Norhayati; Hashim, Noor Hasani; Shuib, Nor Shifa

2015-01-01

The analysis of aflatoxins (B1, B2, G1 and G2) and ochratoxin A (OTA) was performed in processed spices marketed in Penang, Malaysia, using immunoaffinity columns and HPLC equipped with fluorescence detector (HPLC-FD). The processed powdered spices analysed include dried chilli, fennel, cumin, turmeric, black and white pepper, poppy seed, coriander, 'garam masala', and mixed spices for fish, meat and chicken curry. Two different studies were carried out. The limit of detection (LOD) was 0.01 ng g(-1) for each aflatoxin (AF) and 0.10 ng g(-1) for OTA (signal-to-noise ratio = 3:1). In the first study, 34 commercial processed spices analysed with a mean level, range and incidence of positive samples for total AF were 1.61 ng g(-1), 0.01-9.34 ng g(-1) and 85%, respectively, and for AFB1 were 1.38 ng g(-1), 0.01-7.68 ng g(-1) and 85%, respectively. The mean level, range and incidence of positive samples for OTA were 2.21 ng g(-1), 0.14-20.40 ng g(-1) and 79%, respectively. Natural co-occurrence of AF and OTA was found in 25 (74%) samples. In the second study of 24 commercial processed spices, the mean level, range and incidence of positive samples for total AF were 8.38 ng g(-1), 0.32-31.17 ng g(-1) and 88%, respectively, and for AFB1 were 7.31 ng g(-1), 0.32-28.43 ng g(-1) and 83%, respectively. Fifteen positive samples for total AF and two positive samples for OTA exceeded the permissible Malaysian limit of 5 ng g(-1). Contamination of both mycotoxins in spices may represent another route of exposure to consumers due to their frequent and prolonged consumption, as spices are common ingredients in popular dishes among Asian countries.

Identification of Ochratoxin A Producing Fungi Associated with Fresh and Dry Liquorice

PubMed Central

Chen, Amanda Juan; Tang, Dan; Zhou, Ying Qun; Sun, Bing Da; Li, Xiao Jin; Wang, Li Zhi; Gao, Wei Wei

2013-01-01

The presence of fungi on liquorice could contaminate the crop and result in elevated levels of mycotoxin. In this study, the mycobiota associated with fresh and dry liquorice was investigated in 3 producing regions of China. Potential toxigenic fungi were tested for ochratoxin A (OTA) and aflatoxin B1 (AFB1) production using liquid chromatography/mass spectrometry/mass spectrometry. Based on a polyphasic approach using morphological characters, β-tubulin and RNA polymerase II second largest subunit gene phylogeny, a total of 9 genera consisting of 22 fungal species were identified, including two new Penicillium species (Penicillium glycyrrhizacola sp. nov. and Penicillium xingjiangense sp. nov.). The similarity of fungal communities associated with fresh and dry liquorice was low. Nineteen species belonging to 8 genera were detected from fresh liquorice with populations affiliated with P. glycyrrhizacola, P. chrysogenum and Aspergillus insuetus comprising the majority (78.74%, 33.33% and 47.06% of total) of the community from Gansu, Ningxia and Xinjiang samples, respectively. In contrast, ten species belonging to 4 genera were detected from dry liquorice with populations affiliated with P. chrysogenum, P. crustosum and Aspergillus terreus comprising the majority (64.00%, 52.38% and 90.91% of total) of the community from Gansu, Ningxia and Xinjiang samples, respectively. Subsequent LC/MS/MS analysis indicated that 5 fungal species were able to synthesize OTA in vitro including P. chrysogenum, P. glycyrrhizacola, P. polonicum, Aspergillus ochraceus and A. westerdijkiae, the OTA concentration varied from 12.99 to 39.03 µg/kg. AFB1 was absent in all tested strains. These results demonstrate the presence of OTA producing fungi on fresh liquorice and suggest that these fungi could survive on dry liquorice after traditional sun drying. Penicillium chrysogenum derived from surrounding environments is likely to be a stable contributor to high OTA level in liquorice. The harvesting and processing procedure needs to be monitored in order to keep liquorice free of toxigenic fungi. PMID:24205182

Determination of ochratoxin A in fruit juice by high-performance liquid chromatography after vortex-assisted emulsification microextraction based on solidification of floating organic drop.

PubMed

Asadi, Mohammad

2018-03-01

A rapid, simple, and green vortex-assisted emulsification microextraction method based on solidification of floating organic drop was developed for the extraction and determination of ochratoxin A (OTA) with high-performance liquid chromatography. Some factors influencing the extraction efficiency of OTA such as the type and volume of extraction solvent, sample pH, salt concentration, vortex time, and sample volume were optimized. Under optimized conditions, the calibration curve exhibited linearity in the range of 50.0-500 ng L -1 with a coefficient of determination higher than 0.999. The limit of detection was 15.0 ng L -1 . The inter- and intra-assays relative standard deviations were in a range of 4.7-8.7%. The accuracy of the developed method was investigated through recovery experiments, and it was successfully used for the quantification of OTA in 40 samples of fruit juice.

Genetic evolution of nevus of Ota reveals clonal heterogeneity acquiring BAP1 and TP53 mutations.

PubMed

Vivancos, Ana; Caratú, Ginevra; Matito, Judit; Muñoz, Eva; Ferrer, Berta; Hernández-Losa, Javier; Bodet, Domingo; Pérez-Alea, Mileidys; Cortés, Javier; Garcia-Patos, Vicente; Recio, Juan A

2016-03-01

Melanoma presents molecular alterations based on its anatomical location and exposure to environmental factors. Due to its intrinsic genetic heterogeneity, a simple snapshot of a tumor's genetic alterations does not reflect the tumor clonal complexity or specific gene-gene cooperation. Here, we studied the genetic alterations and clonal evolution of a unique patient with a Nevus of Ota that developed into a recurring uveal-like dermal melanoma. The Nevus of Ota and ulterior lesions contained GNAQ mutations were c-KIT positive, and tumors showed an increased RAS pathway activity during progression. Whole-exome sequencing of these lesions revealed the acquisition of BAP1 and TP53 mutations during tumor evolution, thereby unmasking clonal heterogeneity and allowing the identification of cooperating genes within the same tumor. Our results highlight the importance of studying tumor genetic evolution to identify cooperating mechanisms and delineate effective therapies. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Simultaneous determination of ochratoxin A, B and citrinin in foods by HPLC-FL and LC/MS/MS].

PubMed

Tabata, Setsuko; Iida, Kenji; Kimura, Keisuke; Iwasaki, Yumiko; Nakazato, Mitsuo; Kamata, Kunihiro; Hirokado, Masako

2008-04-01

Methods using high-performance liquid chromatography with fluorescence detection (HPLC-FL) and using liquid chromatography with tandem mass spectrometry (LC/MS/MS) were developed for simultaneous determination of ochratoxin A (OTA), ochratoxin B (OTB) and citrinin (CIT) in cereal, fruit, and coffee products. The samples were extracted with ethyl acetate under an acidic condition, and then cleaned up with liquid-liquid separation. The test solutions were analyzed by reverse-phase HPLC-FL and LC/MS/MS. Mass spectral acquisition was performed in positive ion mode by applying multiple reaction monitoring. The performances of both detectors were almost equivalent. The recoveries of OTA and OTB were 87-111%, and that of CIT were 70-88%. The limits of quantification (S/N> or =10) of OTA, OTB and CIT was 0.1 mug/kg or less. These methods were considered to be useful for the determination of the three mycotoxins at low levels (0.1 microg/kg).

Prevalence of toxigenic Penicillium species associated with poultry house in Telangana, India.

PubMed

Koteswara Rao, Vankudoth; Girisham, Sivadevuni; Madhusudhan Reddy, Solipuram

2016-11-01

The prevalence of mycotoxigenic Penicillium species in poultry houses of Telangana, India, was studied during 4 seasons between June 2009 and May 2010. Fungi belonging to 13 genera, including Penicillium, comprising 43 species were collected using petri plates. Fourteen Penicillium species demonstrated varying degrees of mycotoxigenicity. Chemical and chromatographic analysis of the different poultry feed samples revealed 8 different mycotoxins with ochratoxin A (OTA) predominating. The mean contamination rate of OTA was 38%. OTA quantities ranged between 5.78 and 6.73 µg/kg -1 , 10.13 and 14.23 µg/kg -1 , and 12.33 and 15.20 µg/kg -1 in starter, broiler, and layer feeds, respectively. Statistically significant positive correlation between prevalence of Penicillium species and the monsoon, autumn, and spring seasons and negative correlation between prevalence and the autumn, spring, and summer seasons were observed. These findings may serve as risk exposure indicators and contribute toward the initiation of a sustainable control program.

Influence of physical and chemical characteristics of wine grapes on the incidence of Penicillium and Aspergillus fungi in grapes and ochratoxin A in wines.

PubMed

Freire, Luísa; Passamani, Fabiana Reinis Franca; Thomas, Ariela Betsy; Nassur, Rita de Cássia Mirela Resende; Silva, Lais Mesquita; Paschoal, Fabiano Narciso; Pereira, Giuliano Elias; Prado, Guilherme; Batista, Luís Roberto

2017-01-16

The incidence of filamentous fungi and toxin levels in grapes and wines varies depending on the variety of grapes, the wine region, agricultural practices, weather conditions, the harvest and the winemaking process. In this sense, the objective of this study was to evaluate the diversity of Aspergillus and Penicillium fungi isolated from wine grapes of the semi-arid tropical region of Brazil, evaluate the presence of ochratoxin A (OTA) in the experimental wine and verify if there is a correlation between occurrence of these fungi and the physicochemical characteristics of the wine grapes grown in the region. For the isolation of fungi we used the direct plating technique. The presence of OTA in the experimental wine was detected by high-performance liquid chromatography. The species found were Aspergillus niger, A. carbonarius, A. aculeatus, A. niger Aggregate, A. flavus, A. sojae, Penicillium sclerotiorum, P. citrinum, P. glabrum, P. decumbens, P. solitum and P. implicatum. All isolates of A. carbonarius were OTA producers and all P. citrinum were citrinin producers. The highest concentration of OTA was found in red wine (0.29μg/L). All species identified in this study, except A. flavus, showed a positive correlation with at least one physicochemical parameter assessed, highlighting the pectin content, total sugar, total acidity and phenolic compounds. Copyright © 2016 Elsevier B.V. All rights reserved.

A polyphenol-enriched cocoa extract reduces free radicals produced by mycotoxins.

PubMed

Corcuera, L A; Amézqueta, S; Arbillaga, L; Vettorazzi, A; Touriño, S; Torres, J L; López de Cerain, A

2012-03-01

Polyphenols are characterized by the presence of phenol units in the molecules. These compounds may show antioxidant ability by scavenging reactive oxygen species (ROS) of the free radical type. A polyphenol enriched cocoa extract (PECE) was obtained from cocoa seeds with 28% of procyanidins which were mainly epicatechin oligomers. PECE was very active as free radical scavenger against 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and tris(2,4,6-trichloro-3,5-dinitrophenyl)methyl (HNTTM) radicals; and the tris(2,3,5,6-tetrachloro-4-nitrophenyl)methyl (TNPTM) assay showed that the PECE might not be pro-oxidant. Thus it was considered a good candidate to be tested in in vitro models. It showed mild cytotoxic power on Hep G2 cells and induced ROS in a dose-dependent manner being weak oxidant only at high concentrations near the limit of solubility. The antioxidant properties were assayed in Hep G2 treated with the mycotoxins ochratoxin A (OTA) and/or aflatoxin B1 (AFB1). The PECE was not effective against AFB1 but it increased the cell viability and reduced significantly the amounts of ROS in cells treated with OTA or mixtures of AFB1+OTA. These results are coherent with the role of oxidative pathways in the mechanism of OTA and indicate that polyphenols extracted from cocoa may be good candidates as antioxidant agents. Copyright © 2011 Elsevier Ltd. All rights reserved.

Magnetic nanoparticles solid phase extraction for determination of ochratoxin A in cereals using high-performance liquid chromatography with fluorescence detection.

PubMed

Mashhadizadeh, Mohammad Hossein; Amoli-Diva, Mitra; Pourghazi, Kamyar

2013-12-13

A new, simple, fast, and environmental friendly sample preconcentration technique based on the modified Fe3O4 nanoparticles has been developed for extraction, and determination of ochratoxin A (OTA). Magnetic nanoparticles were coated with 3-(trimethoxysilyl)-1-propanethiol and modified by ethylene glycol bis-mercaptoacetate. Transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectrometry were used to characterize the adsorbents and the main parameters affecting the extraction and desorption efficiencies, such as pH of sample solution, sample volume, desorption conditions, extraction and desorption times, salt addition, and co-existing interferences have been investigated and established. Under optimal conditions, OTA was extracted and analyzed using high performance liquid chromatography with fluorescence detection. The mobile phase consists of acetonitrile:water:acetic acid (99:99:2, v/v/v) and fluorescence detection was performed with excitation and emission wavelengths at 333 and 477nm, respectively. An enrichment factor of 24 was achieved for OTA with relative standard deviation of <7%. The proposed method was applied to twenty samples of cereals (rice, wheat, and corn). The limits of detection of 0.06, 0.03, and 0.05ngmL(-1) and limits of quantitation of 0.19, 0.11, and 0.15ngmL(-1), were found for rice, wheat, and corn samples, respectively. The recoveries of OTA for spiked samples were ranged from 87 to 93%. Copyright © 2013 Elsevier B.V. All rights reserved.

Reappraisal of the 2010 Maule, 2014 Iquique, 2015 Illapel through Inversion of Geodetic Data and Tsunami Waveforms Using the Optimal Time Alignment (OTA) Method

NASA Astrophysics Data System (ADS)

Romano, F.; Lorito, S.; Piatanesi, A.; Volpe, M.; Lay, T.; Tolomei, C.; Murphy, S.; Tonini, R.; Escalante, C.; Castro, M. J.; Gonzalez-Vida, J. M.; Macias, J.

2017-12-01

The Chile subduction zone is one of the most seismically active regions in the world and it hosted a number of great tsunamigenic earthquakes in the past. In particular, during the last 7 years three M8+ earthquakes occurred nearby the Chilean coasts, that is the 2010 M8.8 Maule, the 2014 M8.1 Iquique, and the M8.3 2015 Illapel earthquakes. The rupture process of these earthquakes has been studied by using different kind of geophysical observations such as seismic, geodetic, and tsunami data; in particular, tsunami waveforms are important for constraining the slip on the offshore portion of the fault. However, it has been shown that forward modelling of tsunami data can be affected by unavailability of accurate bathymetric models, especially in the vicinity of the tide-gauges; and in the far field by water density gradients, ocean floor elasticity, or geopotential gravity changes, generally neglected. This could result in a mismatch between observed and predicted tsunami signals thus affecting the retrieved tsunami source image. Recently, a method has been proposed for automatic correction during the nonlinear inversion of the mismatch (optimal time alignment, OTA; Romano et al., GRL, 2016). Here, we present a reappraisal of the joint inversion of tsunami data with OTA procedure and geodetic data, for the Maule, Iquique, and Illapel earthquakes. We compare the results with those obtained by tsunami inversion without using OTA and with other published inversion results.

Influence of high-pressure processing on the generation of γ-aminobutyric acid and microbiological safety in coffee beans.

PubMed

Chen, Bang-Yuan; Huang, Hsiao-Wen; Cheng, Ming-Ching; Wang, Chung-Yi

2018-04-27

The aim of this study was to investigate the influence of high-pressure processing (HPP) on γ-aminobutyric acid (GABA) content, glutamic acid (Glu) content, glutamate decarboxylase (GAD) activity, growth of Aspergillus fresenii, and accumulated ochratoxin A (OTA) content in coffee beans. The results indicated that coffee beans subjected to HPP at pressures ≥50 MPa for 5 min increased GAD activity and promoted the conversion of Glu to GABA, and showed a significantly doubling of GABA content compared with unprocessed coffee beans. Additionally, investigation of the influence of HPP on A. fresenii growth on coffee beans showed that application ≥400 MPa reduced A. fresenii concentrations to <1 log. Furthermore, during a 50-day storage period, we observed that a processing pressure of 600 MPa completely inhibited A. fresenii growth, and on day 50 the OTA content of coffee beans subjected to processing pressures of 600 MPa was 0.0066 μg g -1 , which was significantly lower than the OTA content of 0.1143 μg g -1 in the control group. This study shows that HPP treatment can simultaneously increase GABA content and inhibit the growth of A. fresenii, thereby effectively reducing the production and accumulation of OTA and maintaining the microbiological safety of coffee beans. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Assessment of global and gene-specific DNA methylation in rat liver and kidney in response to non-genotoxic carcinogen exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ozden, Sibel, E-mail: stopuz@istanbul.edu.tr; Turgut Kara, Neslihan; Sezerman, Osman Ugur

Altered expression of tumor suppressor genes and oncogenes, which is regulated in part at the level of DNA methylation, is an important event involved in non-genotoxic carcinogenesis. This may serve as a marker for early detection of non-genotoxic carcinogens. Therefore, we evaluated the effects of non-genotoxic hepatocarcinogens, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), hexachlorobenzene (HCB), methapyrilene (MPY) and male rat kidney carcinogens, d-limonene, p-dichlorobenzene (DCB), chloroform and ochratoxin A (OTA) on global and CpG island promoter methylation in their respective target tissues in rats. No significant dose-related effects on global DNA hypomethylation were observed in tissues of rats compared to vehicle controls using LC–MS/MSmore » in response to short-term non-genotoxic carcinogen exposure. Initial experiments investigating gene-specific methylation using methylation-specific PCR and bisulfite sequencing, revealed partial methylation of p16 in the liver of rats treated with HCB and TCDD. However, no treatment related effects on the methylation status of Cx32, e-cadherin, VHL, c-myc, Igfbp2, and p15 were observed. We therefore applied genome-wide DNA methylation analysis using methylated DNA immunoprecipitation combined with microarrays to identify alterations in gene-specific methylation. Under the conditions of our study, some genes were differentially methylated in response to MPY and TCDD, whereas d-limonene, DCB and chloroform did not induce any methylation changes. 90-day OTA treatment revealed enrichment of several categories of genes important in protein kinase activity and mTOR cell signaling process which are related to OTA nephrocarcinogenicity. - Highlights: • Studied non-genotoxic carcinogens caused no change on global DNA hypomethylation. • d-Limonene, DCB and chloroform did not show any genome-wide methylation changes. • Some genes were differentially methylated in response to MPY, TCDD and OTA. • Protein kinase activity and mTOR cell signaling are involved in OTA carcinogenicity. • Our data highlight Cpne4 may be a potential biomarker for non-genotoxic carcinogens.« less

[Teamwork in the operating theatre: the German Observational Teamwork Assessment for Surgery (OTAS-D) and its first application in Germany].

PubMed

Passauer-Baierl, S; Chiapponi, C; Bruns, C J; Weigl, M

2014-12-01

The quality of surgical teamwork contributes to performance of the operating theatre team, service quality and patient safety in surgery. Observational tools are a feasible and reliable way to capture and evaluate teamwork in the operating theatre (OT). We introduce the German version of the Observational Teamwork Assessment for Surgery (OTAS-D) and present the first observational results from German OTs. Quality of surgical teamwork was assessed with observational teamwork assessment for surgery (OTAS-D). It evaluates five dimensions of OT teamwork: communication, coordination, cooperation/backup behaviour, leadership, and team monitoring/situation awareness. Each dimension is evaluated for each profession (surgical, nursing, and anaesthesia team) as well for each phase of the procedure (pre-, intra-, and post-operative). We observed n = 63 procedures, mainly in abdominal/general and orthopaedic surgery. Additionally, all OT team members scored their individual evaluation of the intra-operative teamwork (standardised 1-item questions). The OTAS-D evaluations showed meaningful results and differences for the OT professions as well as across the different phases of the procedures. Overall, a medium to good level of the OT teamwork was observed. There were no differences in regard to type of surgery (minimally invasive vs. open) or surgical specialties. With an increased coordination of the surgical team we observed a significantly increased cooperation of the nursing team (r = 0.36, p = 0.004). Concerning the OT staffs self-reports, the surgical and nursing teams reported higher scores for quality of surgical teamwork during the procedure than their anaesthesia team members. No significant relationships between observed quality of OT teamwork and self-reports were found. The German version of OTAS-D is a psychometrically robust method to capture the quality of teamwork in operating theatres. It enables the analyses of teamwork between the surgical, nursing and anaesthesia professions in acute surgical care. Limitations of the first application results are considered. Finally, potential applications for surgical teaching, research and quality management are discussed. Georg Thieme Verlag KG Stuttgart · New York.

Open-to-Air Is a Viable Option for Initial Wound Care in Necrotizing Soft Tissue Infection that Allows Early Detection of Recurrence without Need for Painful Dressing Changes or Return to Operating Room.

PubMed

Yang, Derek; Davies, April; Burge, Bailey; Watkins, Phillip; Dissanaike, Sharmila

2018-01-01

The standard treatment of necrotizing soft tissue infection (NSTI) includes extensive surgical debridement. Care of these debridements is challenging because of the size of the wound and associated pain. A potential solution is to leave the wounds open-to-air in the period after the initial debridement, allowing for regular inspection at bedside while reducing pain associated with frequent dressing changes. We evaluated the feasibility of this approach from a pain control standpoint. An audit of wound care modalities used on adult patients with NSTI admitted to a regional burn center between January 2009 and May 2014 was performed. Patients with at least one operation were included. Those opting for palliative care were excluded. Wound care was divided into four categories: open-to-air (OTA), negative-pressure wound therapy (NPWT), packing, and ointment. Wound care, pain score, pain medication use, and number of operations were collected for the first seven days after initial debridement. Pain management was assessed by pain scores. Analgesic use was measured and compared using conversion to morphine milligram equivalents (MME). Ninety-six patients were included; 67% were men with average age of 50 years, resulting in a total of 672 days of wound care evaluated: 69 days of OTA, 127 days of NPWT, 200 days of packing, and 126 days of ointment (150 days were undocumented). Average daily pain score from all wound care modalities was 2.00. Negative pressure wound therapy had the highest reported daily pain score (2.18, p = 0.034), whereas OTA had the lowest pain score (1.63, p < 0.05). Mortality was lower in the OTA cohort but was not statistically significant; there were no other differences in long-term outcome. Leaving wounds OTA is a safe and viable option in the immediate post-debridement period of NSTI to reduce pain, while permitting frequent re-evaluation for quick recognition of disease progression and repeat operative debridement if necessary.

Ochratoxin A and citrinin loads in stored wheat grains: impact of grain dust and possible prediction using ergosterol measurement.

PubMed

Tangni, E K; Pussemier, L

2006-02-01

Crop storage should be carried out under hygienic conditions to ensure safe products, but sometimes grain dust which has settled from previous storage may be left over and incorporated to the following stored grains. This paper describes the results obtained using a lab model developed in order to assess the impact of grain dust incorporation for its direct contribution as a contaminant but also as an inoculum in stored wheat. Settled grain dust (4 samples) released from Belgian grain storages were collected and analysed by HPLC for ergosterol, ochratoxin A (OTA) and citrinin (CIT) content. For OTA and for ergosterol, there was a high degree of variability in concentrations found in the dust samples (from 17.3-318 ng g(-1) and from 39-823 microg g(-1), respectively) whilst for CIT, the range was less significant (from 137-344 ng g(-1)). Incorporation of grain dust into wheat storage contributed to an increase in the concentrations of mycotoxins in the stored grain. Dust acts as a contaminant and as an inoculum. According to these two ways, patterns of mycotoxin generation vary with the nature of the mycotoxin, the mycotoxigenic potential of dust and the water activity of the wheat. OTA and CIT showed a very versatile image when considering the amounts of toxins produced under the selected experimental conditions. The development of a robust tool to forecast the mycotoxigenicity of dust was based on the determination of ergosterol content as a general marker of fungal biomass. Present results suggest that this predictive tool would only be valid for predicting the contamination level of CIT and OTA at reasonable moisture content (14-20%). The potential risk of having highly contaminated batches from stock to stock may thus occur and this paper discusses possible pathways leading to OTA and CIT contamination either under wet or dry storage conditions. We therefore, recommend taking precautionary measures not only by controlling and maintaining moisture at a reasonable level during storage of the raw materials but also by paying more attention to the cleaning of the stores before loading in the new harvests.

Increase of fumonisin b2 and ochratoxin a production by black Aspergillus species and oxidative stress in grape berries damaged by powdery mildew.

PubMed

Cozzi, Giuseppe; Paciolla, Costantino; Haidukowski, Miriam; De Leonardis, Silvana; Mulè, Giuseppina; Logrieco, Antonio

2013-12-01

Powdery mildew (PM), caused by the fungus Erysiphe necator, is one of the most widespread fungal disease of grape and may cause extensive openings on the berry surface during the infection. We evaluated the effect of damage caused by PM in grape berries on the growth of and mycotoxin production by Aspergillus and on the oxidative stress in infected berries. Berries of Vitis vinifera L. cv. Negroamaro with sound skin (SS) and those naturally infected by PM were surface sterilized and inoculated with either fumonisin B2(FB2)-producing strains of Aspergillus niger or ochratoxin A (OTA)-producing strains of Aspergillus carbonarius and incubated at 20 and 30°C. The PM berries were significantly more susceptible to both Aspergillus colonization (5 to 15 times more susceptible) and OTA and FB2 contamination (2 to 9 times more susceptible) than were SS berries. The highest toxin concentration was detected in inoculated PM berries both for OTA (9 ng/g) at 20°C and for FB2 (687 ng/g) at 30°C. In inoculated SS and PM berries, although malondialdehyde and hydrogen peroxide concentrations did not increase, the two black Aspergillus species caused a significant decrease in ascorbate content, thus inducing a pro-oxidant effect. These results indicate that grape berries affected by PM are more susceptible to black Aspergillus growth and to production and/or accumulation of FB2 and OTA. Thus, preventive control of E. necator on grape berries could reduce the mycotoxicological risk from black Aspergillus infection.

Analysis of Mycotoxins in Beer Using a Portable Nanostructured Imaging Surface Plasmon Resonance Biosensor.

PubMed

Joshi, Sweccha; Annida, Rumaisha M; Zuilhof, Han; van Beek, Teris A; Nielen, Michel W F

2016-11-02

A competitive inhibition immunoassay is described for the mycotoxins deoxynivalenol (DON) and ochratoxin A (OTA) in beer using a portable nanostructured imaging surface plasmon resonance (iSPR) biosensor, also referred to as imaging nanoplasmonics. The toxins were directly and covalently immobilized on a 3-dimensional carboxymethylated dextran (CMD) layer on a nanostructured iSPR chip. The assay is based on competition between the immobilized mycotoxins and free mycotoxins in the solution for binding to specific antibodies. The chip surface was regenerated after each cycle, and the combination of CMD and direct immobilization of toxins allowed the chips to be used for more than 450 cycles. The limits of detection (LODs) in beer were 17 ng/mL for DON and 7 ng/mL for OTA (or 0.09 ng/mL after 75 times enrichment). These LODs allowed detection of even less than 10% depletion of the tolerable daily intake of DON and OTA by beer. Significant cross-reactivity of anti-DON was observed toward DON-3-glucoside and 3-acetyl-DON, while no cross-reactivity was seen for 15-acetyl-DON. A preliminary in-house validation with 20 different batches of beer showed that both toxins can be detected at the considered theoretical safe level for beer. The assay can be used for in-field or at-line detection of DON in beer and also in barley without preconcentration, while OTA in beer requires an additional enrichment step, thus making the latter in its present form less suitable for field applications.

Publication Productivity of Early-Career Orthopedic Trauma Surgeons.

PubMed

Hake, Mark E; Lee, John J; Goulet, James A

2016-01-01

The goals of this study were to: (1) define the publication productivity of early-career orthopedic trauma surgeons over time; (2) compare the early-career publication productivity of recent orthopedic trauma fellowship graduates vs their more senior colleagues; and (3) determine the proportion of fellowship graduates who meet the Orthopaedic Trauma Association (OTA) publication criteria for active membership early in their careers. Orthopedic trauma fellowship graduates from 1982 to 2007 were analyzed. A literature search was performed for each fellow's publications for the 6-year period beginning the year of fellowship graduation. Publication productivity was compared between early and recent groups of graduates, 1987 to 1991 and 2003 to 2007, respectively. Fulfillment of OTA publication criteria was determined. Seventy-nine percent of graduates contributed to 1 or more publications. The recent group produced more total publications per graduate (4.06 vs 3.29, P=.01) and more coauthor publications (2.60 vs 2.04, P=.019) than the early group. The number of first-author publications did not differ between groups (1.46 vs 1.25, P=.26). A greater percentage of the recent group met current OTA publication criteria compared with the early group (51% vs 35%, P=.04). The findings showed that recent orthopedic trauma graduates had increased publication productivity compared with their more senior colleagues, although a proportion had not qualified for active OTA membership 6 years into their career. Overall, these data are encouraging and suggest that young orthopedic trauma surgeons remain committed to sustaining a high level of academic excellence. Copyright 2016, SLACK Incorporated.

High-performance and versatile electrochemical aptasensor based on self-supported nanoporous gold microelectrode and enzyme-induced signal amplification.

PubMed

Shi, Lei; Rong, Xiaojiao; Wang, Yan; Ding, Shiming; Tang, Wanying

2018-04-15

Herein, novel and versatile electrochemical aptasensors were constructed on a self-supported nanoporous gold (np-Au) microelectrode, integrating with an exonuclease III (Exo III) induced signal amplification strategy. Self-supported np-Au microelectrode with 3D bicontinuous nanoporous structures possesses tremendously large specific area, clean surface, high stability and biocompatibility, bringing about significant advantages in both molecular recognition and signal response. As paradigms, two analytes of bisphenol A (BPA) and ochratoxin A (OTA) were selected to demonstrate the superiority and versatility of designed aptasensors. Trace amounts of mDNA (associated with BPA or OTA concentration) hybridized with cDNA strands assembled on np-Au microelectrode, activating the cleavage reaction with Exo III. Thus, cDNA was digested and mDNA was released to undergo a new hybridization and cleavage cycle. Finally, residual cDNA strands were recognized by methylene blue labelled rDNA/AuNPs with the assistance of hDNA to generate the electrochemical signals, which were used to quantitatively monitor targets. Under the optimized conditions, prepared aptasensors exhibited wide linear ranges (25pg/mL to 2ng/mL for BPA, 10pg/mL to 5ng/mL for OTA) with ultralow detection limits (10pg/mL for BPA, 5pg/mL for OTA), excellent selectivity and stability, and reliable detection in real samples. This work opens a new horizon for constructing promising electrochemical aptasensors for environmental monitoring, medical diagnostics and food safety. Copyright © 2017 Elsevier B.V. All rights reserved.

Amplified impedimetric aptasensor based on gold nanoparticles covalently bound graphene sheet for the picomolar detection of ochratoxin A.

PubMed

Jiang, Ling; Qian, Jing; Yang, Xingwang; Yan, Yuting; Liu, Qian; Wang, Kan; Wang, Kun

2014-01-02

An amplified electrochemical impedimetric aptasensor for ochratoxin A (OTA) was developed with picomolar sensitivity. A facile route to fabricate gold nanoparticles covalently bound reduced graphene oxide (AuNPs-rGO) resulted in a large number of well-dispersed AuNPs on graphene sheets with tremendous binding sites for DNA, since the single rGO sheet and each AuNP can be loaded with hundreds of DNA strands. An aptasensor with sandwich model was fabricated which involved thiolated capture DNA immobilized on a gold electrode to capture the aptamer, then the sensing interface was incubated with OTA at a desired concentration, followed by AuNPs-rGO functionalized reporter DNA hybridized with the residual aptamers. By exploiting the AuNPs-rGO as an excellent signal amplified platform, a single hybridization event between aptamer and reporter DNA was translated into more than 10(7) redox events, leading to a substantial increase in charge-transfer resistance (Rct) by 7~ orders of magnitude compared with that of the free aptamer modified electrode. Such designed aptasensor showed a decreased response of Rct to the increase of OTA concentrations over a wide range of 1 pg mL(-1)-50 ng mL(-1) and could detect extremely low OTA concentration, namely, 0.3 pg mL(-1) or 0.74 pM, which was much lower than that of most other existed impedimetric aptasensors. The signal amplification platform presented here would provide a promising model for the aptamer-based detection with a direct impedimetric method. Copyright © 2013 Elsevier B.V. All rights reserved.

Simultaneous determination of four aflatoxins and ochratoxin A in ginger after inoculation with fungi by ultra-fast liquid chromatography-tandem mass spectrometry.

PubMed

Yang, Ying; Wen, Jing; Kong, Weijun; Liu, Qiutao; Luo, Hongli; Wang, Jian; Yang, Meihua

2016-09-01

Aflatoxins (AFs) and ochratoxin A (OTA) have been detected frequently in food, agricultural products and traditional Chinese medicines, and their presence poses serious health and economic problems worldwide. Ginger can easily be polluted with mycotoxins. In this study, ginger samples were cultivated for 15 days after inoculation with fungi and were prepared based on ultrasound-assisted solid-liquid extraction using methanol/water followed by immunoaffinity column clean-up and analysed by ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) for AFs and OTA. The limits of detection and quantification of AFs and OTA were 0.04-0.30 µg mL(-1) and 0.125-1.0 µg mL(-1) , respectively. The recoveries were 82.0-100.2%. After 15 days' cultivation, no macroscopic mildew was found in ginger. But, the content of AFB1 expressed an increasing trend in ginger, peel [less than the limit of quantification (LOQ)] to the innermost layer (51.86 µ mL(-1) ), AFB2 was only detected in the innermost layer at the level of 0.87 µ mL(-1) . A small amount (

Movement Integration and the One-Target Advantage.

PubMed

Hoffmann, Errol R

2017-01-01

The 1-target advantage (OTA) has been found to occur in many circumstances and the current best explanation for this phenomenon is that of the movement integration hypothesis. The author's purpose is twofold: (a) to model the conditions under which there is integration of the movement components in a 2-component movement and (b) to study the factors that determine the magnitude of the OTA for both the first and second component of a 2-component movement. Results indicate that integration of movement components, where times for one component are affected by the geometry of the other component, occurs when 1 of the movement components is made ballistically. Movement components that require ongoing visual control show only weak interaction with the second component, whereas components made ballistically always show movement time dependence on first and second component amplitude, independent of location within the sequence. The OTA is present on both the first and second components of the movement, with a magnitude that is dependent on whether the components are performed ballistically or with ongoing visual control and also on the amplitudes and indexes of difficulty of the component movements.

Autoradiographic demonstration of oxytocin-binding sites in the macula densa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoeckel, M.E.; Freund-Mercier, M.J.

1989-08-01

Specific oxytocin (OT)-binding sites were localized in the rat kidney with use of a selective {sup 125}I-labeled OT antagonist ({sup 125}I-OTA). High concentrations of OT binding sites were detected on the juxtaglomerular apparatus with use of the conventional film autoradiographic technique. No labeling occurred on other renal structures. The cellular localization of the OT binding sites within the juxtaglomerular apparatus was studied in light microscope autoradiography, on semithin sections from paraformaldehyde-fixed kidney slices incubated in the presence of {sup 125}I-OTA. These preparations revealed selective labeling of the macula densa, mainly concentrated at the basal pole of the cells. Control experimentsmore » showed first that {sup 125}I-OTA binding characteristics were not noticeably altered by prior paraformaldehyde fixation of the kidneys and second that autoradiographic detection of the binding sites was not impaired by histological treatments following binding procedures. In view of the role of the macula densa in the tubuloglomerular feedback, the putative OT receptors of this structure might mediate the stimulatory effect of OT on glomerular filtration.« less

Thermal Design and Analysis of the Optical Telescope Assembly for the Gondola for High Altitude Planetary Science

NASA Technical Reports Server (NTRS)

O'Connor, Brian; Brooks, Thomas

2017-01-01

The NASA Gondola for High Altitude Planetary Science (GHAPS) project is an effort to design, build, and fly a balloon-borne platform for planetary science missions. GHAPS observations will be in the 300 nm to 5 micron wavelength region covering UV, visible, and near-mid IR. The primary element of the project is the Optical Telescope Assembly (OTA). It is a one meter aperture narrow-field-of-view telescope that contains the primary and secondary mirrors, the support system/metering structure, a secondary mirror focusing system, baffles, and insulation. This paper presents the thermal design and analysis that has been done to support the design of the OTA. A major part of the thermal analysis was bounding the flight environment for the six potential Columbia Scientific Balloon Facility launch sites. These analyses were used to give input into the Structural Thermal Optical Performance (STOP) analysis of the telescope. Also the analysis was used to select heater sizes for the few OTA associated electronic components. Currently the telescope is scheduled to have its first flight in 2019.

Trinary flip-flops using Savart plate and spatial light modulator for optical computation in multivalued logic

NASA Astrophysics Data System (ADS)

Ghosh, Amal K.; Basuray, Amitabha

2008-11-01

The memory devices in multi-valued logic are of most significance in modern research. This paper deals with the implementation of basic memory devices in multi-valued logic using Savart plate and spatial light modulator (SLM) based optoelectronic circuits. Photons are used here as the carrier to speed up the operations. Optical tree architecture (OTA) has been also utilized in the optical interconnection network. We have exploited the advantages of Savart plates, SLMs and OTA and proposed the SLM based high speed JK, D-type and T-type flip-flops in a trinary system.

Balkan Endemic Nephropathy - Still continuing enigma, risk assessment and underestimated hazard of joint mycotoxin exposure of animals or humans.

PubMed

Stoev, Stoycho D

2017-01-05

The spreading of mycotoxic nephropathy in animals/humans was studied. The possible etiological causes provoking this nephropathy were carefully reviewed and analyzed. The natural content of the most frequent nephrotoxic mycotoxins in target feedstuffs/foods were investigated, in addition to their significance for development of renal damages in endemic areas. An estimation of the level of exposure of humans to the nephrotoxic mycotoxin, ochratoxin A (OTA), is made. The possible synergism or additive effects between some target mycotoxins in the development of nephropathy is also covered. The significance of joint mycotoxin interaction and masked mycotoxins, in addition to some newly isolated fungal toxic agents in the complicated etiology of mycotoxic nephropathy ranged in Balkan countries is discussed. The importance of some target fungal species which can induce kidney damages was evaluated. The morphological/ultrastructural, functional and toxicological similarities between human and animal nephropathy are studied. The possible hazard of low content of combinations of some target mycotoxins in food or feedstuff ingested by pigs, chickens or humans under natural conditions is evaluated and a risk assessment was made. Some different but more effective manners of prophylaxis and/or prevention against OTA contamination of feedstuffs/foods are suggested. A survey was made in regard to the best possible ways of veterinary hygiene control of OTA-exposed animals at slaughter time for preventing the entrance of OTA in commercial feedstuffs/food channels with a view to reduce the possible health hazard for humans. The economic efficacy and applicability of such preventive measures is additionally discussed and some practical suggestions are made. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Mycotoxins' activity at toxic and sub-toxic concentrations: differential cytotoxic and genotoxic effects of single and combined administration of sterigmatocystin, ochratoxin A and citrinin on the hepatocellular cancer cell line Hep3B.

PubMed

Anninou, Nikolia; Chatzaki, Ekaterini; Papachristou, Fotini; Pitiakoudis, Muichail; Simopoulos, Constantinos

2014-02-07

Food safety organizations indicate the likelihood of constant human and animal exposure to mycotoxin mixtures as a possible negative public health impact. Risk assessment demonstrates that certain mycotoxins of Aspergillus and Penicillium spp. are toxic and hold a significant genotoxic efficacy at nanomolar concentrations. The aim of the current study was to investigate the potential cytogenetic effects of sterigmatocystin (STER), ochratoxin A (OTA) and citrinin (CTN) alone or in combination, at pM to μΜ concentrations, on the human hepatocellular cancer cell line Hep3B. MTT reduction, mitotic divisions, cell cycle delays and sister chromatid exchange rates (SCE) were determined as endpoints of metabolic activity, cytotoxicity, cytostaticity, and genotoxicity, respectively. All mycotoxin treatments induce SCE rates from 10-12 M, while their cytotoxic and cytostatic potential varies. In PRI and MI assays, but not at MTT, STER alone or in combination with OTA + CTN appeared cytostatic and cytotoxic, even at 10-12 M, while CTN alone and all other combinations displayed substantial cellular survival inhibition in doses ≥ 10-8 M. Co-administration of STER + OTA or STER + CTN in concentrations ≤ 10-1 M, increased the MI and MTT activity, while it did not affect the PRI. Mycotoxin co-treatments revealed in general similar-to-additive or antagonistic genotoxic and cytotoxic effects. Our results for the first time describe that STER alone or in combination with OTA and/or CTN share a cytotoxic and cytogenetic potential even at picoMolar concentrations on human hepatoma cells in vitro.

Is Increased Susceptibility to Balkan Endemic Nephropathy in Carriers of Common GSTA1 (*A/*B) Polymorphism Linked with the Catalytic Role of GSTA1 in Ochratoxin A Biotransformation? Serbian Case Control Study and In Silico Analysis

PubMed Central

Reljic, Zorica; Zlatovic, Mario; Savic-Radojevic, Ana; Pekmezovic, Tatjana; Djukanovic, Ljubica; Matic, Marija; Pljesa-Ercegovac, Marija; Mimic-Oka, Jasmina; Opsenica, Dejan; Simic, Tatjana

2014-01-01

Although recent data suggest aristolochic acid as a putative cause of Balkan endemic nephropathy (BEN), evidence also exists in favor of ochratoxin A (OTA) exposure as risk factor for the disease. The potential role of xenobiotic metabolizing enzymes, such as the glutathione transferases (GSTs), in OTA biotransformation is based on OTA glutathione adducts (OTHQ-SG and OTB-SG) in blood and urine of BEN patients. We aimed to analyze the association between common GSTA1, GSTM1, GSTT1, and GSTP1 polymorphisms and BEN susceptibility, and thereafter performed an in silico simulation of particular GST enzymes potentially involved in OTA transformations. GSTA1, GSTM1, GSTT1 and GSTP1 genotypes were determined in 207 BEN patients and 138 non-BEN healthy individuals from endemic regions by polymerase chain reaction (PCR). Molecular modeling in silico was performed for GSTA1 protein. Among the GST polymorphisms tested, only GSTA1 was significantly associated with a higher risk of BEN. Namely, carriers of the GSTA1*B gene variant, associated with lower transcriptional activation, were at a 1.6-fold higher BEN risk than those carrying the homozygous GSTA1*A/*A genotype (OR = 1.6; p = 0.037). In in silico modeling, we found four structures, two OTB-SG and two OTHQ-SG, bound in a GSTA1 monomer. We found that GSTA1 polymorphism was associated with increased risk of BEN, and suggested, according to the in silico simulation, that GSTA1-1 might be involved in catalyzing the formation of OTHQ-SG and OTB-SG conjugates. PMID:25111321

Oxytocin receptor neurotransmission in the dorsolateral bed nucleus of the stria terminalis facilitates the acquisition of cued fear in the fear-potentiated startle paradigm in rats.

PubMed

Moaddab, Mahsa; Dabrowska, Joanna

2017-07-15

Oxytocin (OT) is a hypothalamic neuropeptide that modulates fear and anxiety-like behaviors. Dorsolateral bed nucleus of the stria terminalis (BNST dl ) plays a critical role in the regulation of fear and anxiety, and expresses high levels of OT receptor (OTR). However, the role of OTR neurotransmission within the BNST dl in mediating these behaviors is unknown. Here, we used adult male Sprague-Dawley rats to investigate the role of OTR neurotransmission in the BNST dl in the modulation of the acoustic startle response, as well as in the acquisition and consolidation of conditioned fear using fear potentiated startle (FPS) paradigm. Bilateral intra-BNST dl administration of OT (100 ng) did not affect the acquisition of conditioned fear response. However, intra-BNST dl administration of specific OTR antagonist (OTA), (d(CH 2 ) 5 1 , Tyr(Me) 2 , Thr 4 , Orn 8 , des-Gly-NH 2 9 )-vasotocin, (200 ng), prior to the fear conditioning session, impaired the acquisition of cued fear, without affecting a non-cued fear component of FPS. Neither OTA, nor OT affected baseline startle or shock reactivity during fear conditioning. Therefore, the observed impairment of cued fear after OTA infusion resulted from the specific effect on the formation of cued fear. In contrast to the acquisition, neither OTA nor OT affected the consolidation of FPS, when administered after the completion of fear conditioning session. Taken together, these results reveal the important role of OTR neurotransmission in the BNST dl in the formation of conditioned fear to a discrete cue. This study also highlights the role of the BNST dl in learning to discriminate between threatening and safe stimuli. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ochratoxin A in raisins and currants: basic extraction procedure used in two small marketing surveys of the occurrence and control of the heterogeneity of the toxins in samples.

PubMed

Möller, T E; Nyberg, M

2003-11-01

A basic extraction procedure for analysis of ochratoxin A (OTA) in currants and raisins is described, as well as the occurrence of OTA and a control of heterogeneity of the toxin in samples bought for two small marketing surveys 1999/2000 and 2001/02. Most samples in the surveys were divided into two subsamples that were individually prepared as slurries and analysed separately. The limit of quantification for the method was estimated as 0.1 microg kg(-1) and recoveries of 85, 90 and 115% were achieved in recovery experiments at 10, 5 and 0.1 microg kg(-1), respectively. Of all 118 subsamples analysed in the surveys, 96 (84%) contained ochratoxin A at levels above the quantification level and five samples (4%) contained more than the European Community legislation of 10 microg kg(-1). The OTA concentrations found in the first survey were in the range < 0.1-19.0 microg kg(-1) with a median concentration of 0.9 microg kg(-1). In the 2001/02 study, the range was < 0.1-34.6 microg kg(-1) with a median of 0.2 microg kg(-1). Big differences were often achieved between individual subsamples of the original sample, which indicate a wide heterogeneous distribution of the toxin. Data from the repeatability test as well as recovery experiments from the same slurries showed that preparation of slurries as described here seemed to give a homogeneous and representative sample. The extraction with the basic sodium bicarbonate-methanol mixture used in the surveys gave similar or somewhat higher OTA values on some samples tested in a comparison with a weak phosphoric acid water-methanol extraction mixture.

Structural Properties, Order–Disorder Phenomena, and Phase Stability of Orotic Acid Crystal Forms

PubMed Central

2016-01-01

Orotic acid (OTA) is reported to exist in the anhydrous (AH), monohydrate (Hy1), and dimethyl sulfoxide monosolvate (SDMSO) forms. In this study we investigate the (de)hydration/desolvation behavior, aiming at an understanding of the elusive structural features of anhydrous OTA by a combination of experimental and computational techniques, namely, thermal analytical methods, gravimetric moisture (de)sorption studies, water activity measurements, X-ray powder diffraction, spectroscopy (vibrational, solid-state NMR), crystal energy landscape, and chemical shift calculations. The Hy1 is a highly stable hydrate, which dissociates above 135 °C and loses only a small part of the water when stored over desiccants (25 °C) for more than one year. In Hy1, orotic acid and water molecules are linked by strong hydrogen bonds in nearly perfectly planar arranged stacked layers. The layers are spaced by 3.1 Å and not linked via hydrogen bonds. Upon dehydration the X-ray powder diffraction and solid-state NMR peaks become broader, indicating some disorder in the anhydrous form. The Hy1 stacking reflection (122) is maintained, suggesting that the OTA molecules are still arranged in stacked layers in the dehydration product. Desolvation of SDMSO, a nonlayer structure, results in the same AH phase as observed upon dehydrating Hy1. Depending on the desolvation conditions, different levels of order–disorder of layers present in anhydrous OTA are observed, which is also suggested by the computed low energy crystal structures. These structures provide models for stacking faults as intergrowth of different layers is possible. The variability in anhydrate crystals is of practical concern as it affects the moisture dependent stability of AH with respect to hydration. PMID:26741914

Discrimination of Aspergillus niger and other Aspergillus species belonging to section Nigri by PCR assays.

PubMed

González-Salgado, Amaia; Patiño, Belén; Vázquez, Covadonga; González-Jaén, M Teresa

2005-04-15

Aspergillus species included in section Nigri are common in plant products and processed food, such as grapes, cereals, coffee and derivatives, particularly in warm and tropical climates. Two of these species, A. carbonarius and A. niger, are known to produce ochratoxin A (OTA), a potent nephrotoxin and carcinogenic to human (group 2B). Recognition of the several species of this section is difficult and requires considerable expertise using conventional methods based on morphological features. In this work we describe rapid, sensitive and robust assays based on the PCR technique to discriminate the main species included in section Nigri: A. japonicus, A. heteromorphus, A. ellipticus and the two morphologically indistinguishable species of the A. niger aggregate: A. niger and A. tubingensis. The species-specific primers have been designed on the basis of ITS (internal transcribed spacers of rDNA units) sequence comparisons obtained from several Aspergillus strains and have been tested in a number of strains from different origins and hosts. These PCR assays, based on multi-copy sequences, are highly sensitive and specific and represent a good tool for an early detection of OTA-producing Aspergillus species in order to prevent OTA from entering the food chain.

Technical and cost advantages of silicon carbide telescopes for small-satellite imaging applications

NASA Astrophysics Data System (ADS)

Kasunic, Keith J.; Aikens, Dave; Szwabowski, Dean; Ragan, Chip; Tinker, Flemming

2017-09-01

Small satellites ("SmallSats") are a growing segment of the Earth imaging and remote sensing market. Designed to be relatively low cost and with performance tailored to specific end-use applications, they are driving changes in optical telescope assembly (OTA) requirements. OTAs implemented in silicon carbide (SiC) provide performance advantages for space applications but have been predominately limited to large programs. A new generation of lightweight and thermally-stable designs is becoming commercially available, expanding the application of SiC to small satellites. This paper reviews the cost and technical advantages of an OTA designed using SiC for small satellite platforms. Taking into account faceplate fabrication quilting and surface distortion after gravity release, an optimized open-back SiC design with a lightweighting of 70% for a 125-mm SmallSat-class primary mirror has an estimated mass area density of 2.8 kg/m2 and an aspect ratio of 40:1. In addition, the thermally-induced surface error of such optimized designs is estimated at λ/150 RMS per watt of absorbed power. Cost advantages of SiC include reductions in launch mass, thermal-management infrastructure, and manufacturing time based on allowable assembly tolerances.

Inhibition of ochratoxigenic moulds by Debaryomyces hansenii strains for biopreservation of dry-cured meat products.

PubMed

Andrade, Maria J; Thorsen, Line; Rodríguez, Alicia; Córdoba, Juan J; Jespersen, Lene

2014-01-17

The ability of the osmotolerant yeast Debaryomyces hansenii to inhibit Penicillium nordicum, the most common ochratoxigenic mould encountered in dry-cured meat products, was evaluated. The antagonistic effect of ten D. hansenii strains isolated from dry-cured ham was screened in vitro using malt extract media and meat extract peptone media with the water activity (a(w)) adjusted to 0.97 and 0.90. A significant inhibition of the two tested P. nordicum strains by D. hansenii cells and cell-free supernatants was observed. At 0.97 a(w), increasing D. hansenii inoculum concentrations significantly improved the inhibition of mould growth on solid medium, whereas at 0.90 a(w) this was not always the case. As observed by bright field microscopy, most D. hansenii strains were able to delay P. nordicum spore germination when co-cultured in malt extract broth. D. hansenii FHSCC 253H showed the highest overall in vitro inhibition of ochratoxigenic mould growth, and was therefore chosen for co-cultivation assays in dry-cured ham slices incubated at 0.94 and 0.84 a(w) simulating ham ripening. Regardless of the experimental conditions tested, lower levels of the inoculated P. nordicum strain were detected in co-cultivation batches compared with batches without D. hansenii. The highest level of mould growth inhibition was observed in batches at 0.94 a(w). Ochratoxin A (OTA) production in ham samples was detected by HPLC-MS. Co-culturing of P. nordicum with D. hansenii FHSCC 253H resulted in lower OTA levels compared with control samples without D. hansenii. The decrease of the mycotoxin presence due to D. hansenii FHSCC 253H was more efficient at 0.94 a(w) (OTA was below the detection limit). In conclusion, D. hansenii is potentially suitable as a biopreservative agent for preventing ochratoxigenic mould growth and OTA accumulation in dry-cured meat products. The inoculation of D. hansenii should be made at the beginning of processing (at the end of post salting) when the a(w) of the product is still high (near 0.94). This action in addition to application of appropriate hygienic actions and control of temperature and relative humidity throughout ripening is required to reduce health risks due to OTA exposure. Copyright © 2013 Elsevier B.V. All rights reserved.

Filling Open Screw Holes in the Area of Metaphyseal Comminution Does Not Affect Fatigue Life of the Synthes Variable Angle Distal Femoral Locking Plate in the AO/OTA 33-A3 Fracture Model.

PubMed

Grau, Luis; Collon, Kevin; Alhandi, Ali; Kaimrajh, David; Varon, Maria; Latta, Loren; Vilella, Fernando

2018-06-01

The aim of this study is to evaluate the biomechanical effect of filling locking variable angle (VA) screw holes at the area of metaphyseal fracture comminution in a Sawbones® (Sawbones USA, Vashon, Washington) model (AO/OTA 33A-3 fracture) using a Synthes VA locking compression plate (LCP) (Depuy Synthes, Warsaw, Indiana). Seven Sawbones® femur models had a Synthes VA-LCP placed as indicated by the manufacturers technique. A 4cm osteotomy was then created to simulate an AO/OTA 33-A3 femoral fracture pattern with metaphyseal comminution. The control group consisted of four constructs in which the open screw holes at the area of comminution were left unfilled; the experimental group consisted of three constructs in which the VA screw holes were filled with locking screws. One of the control constructs was statically loaded to failure at a rate of 5mm/min. A value equal to 75% of the ultimate load to failure was used as the loading force for fatigue testing of 250,000 cycles at 3Hz. Cycles to failure was recorded for each construct and averages were compared between groups. The average number of cycles to failure in the control and experimental groups were 37524±8187 and 43304±23835, respectively (p=0.72). No significant difference was observed with respect to cycles to failure or mechanism of failure between groups. In all constructs in both the control and experimental groups, plate failure reproducibly occurred with cracks through the variable angle holes in the area of bridged comminution. The Synthes VA-LCP in a simulated AO/OTA 33-A3 comminuted metaphyseal femoral fracture fails in a reproducible manner at the area of comminution through the "honeycomb" VA screw holes. Filling open VA screw holes at the site of comminution with locking screws does not increase fatigue life of the Synthes VA-LCP in a simulated AO/OTA 33-A3 distal femoral fracture. Further studies are necessary to determine whether use of this particular plate is contraindicated when bridging distal femoral fractures with metaphyseal comminution.

A high gas fraction, reduced power, syngas bioprocessing method demonstrated with a Clostridium ljungdahlii OTA1 paper biocomposite

PubMed Central

Schulte, Mark J.; Wiltgen, Jeff; Ritter, John; Mooney, Charles B.; Flickinger, Michael C.

2018-01-01

We propose a novel approach to continuous bioprocessing of gases. A miniaturized coated-paper high gas fraction biocomposite absorber has been developed using slowly shaken horizontal anaerobic tubes with concentrated Clostridium ljungdahlii OTA1 absorbing syngas as a model system. These gas absorbers demonstrate elevated CO mass transfer with low power input, reduced liquid requirements, elevated substrate consumption, and increased product secretion compared to shaken suspended cells. We concentrate OTA1 in a cell paste which was coated by extrusion onto chromatography paper. Cell adhesion was by adsorption to the cellulose fibers; visualized by SEM. The C. ljungdahlii OTA1 coated paper mounted above the liquid level absorbs CO and H2 from a model syngas producing acetate with minimal ethanol. At 100 rpm shaking speed (7.7 W m−3) the optimal cell loading is 6.5 gDCW m−2 to maintain high CO absorbing reactivity without the cells coming off of the paper into the liquid phase. Reducing the medium volume from 10 mL to 4 mL (15% of tube volume) did not decrease CO reactivity. The reduced liquid volume increased secreted product concentration by 80%. The specific CO consumption by paper biocomposites was higher at all shaking frequencies <100 rpm than suspended cells under identical incubation conditions. At 25 rpm the biocomposite outperforms suspended cells for CO absorption by 2.5 fold, with a power reduction of 97% over the power input at 100 rpm. The estimated minimum apparent kLa for these biocomposite gas-absorbers is ~100 h−1, a 10 to 104 less power input than other syngas fermentation systems at similar kLa. Specific consumption rates in a biocomposite were measured as ~14 mmol gDCW−1 h−1. This work intensified CO absorption and reactivity by 14 fold to 94 mmol CO m−2 h−1 over previous C. ljungdahlii OTA1 work by our group. Specific acetate production rates were 23 mM h−1 or 46 mmol m−2 h−1. The specific rates and apparent kLa were shown to scale linearly with biocomposite coating area. These proof of concept results will be used to engineer a continuous biocomposite gas absorber bioreactor. PMID:26927418

Ultrasensitive fluorescence immunoassay for detection of ochratoxin A using catalase-mediated fluorescence quenching of CdTe QDs

NASA Astrophysics Data System (ADS)

Huang, Xiaolin; Zhan, Shengnan; Xu, Hengyi; Meng, Xianwei; Xiong, Yonghua; Chen, Xiaoyuan

2016-04-01

Herein, for the first time we report an improved competitive fluorescent enzyme linked immunosorbent assay (ELISA) for the ultrasensitive detection of ochratoxin A (OTA) by using hydrogen peroxide (H2O2)-induced fluorescence quenching of mercaptopropionic acid-modified CdTe quantum dots (QDs). In this immunoassay, catalase (CAT) was labeled with OTA as a competitive antigen to connect the fluorescence signals of the QDs with the concentration of the target. Through the combinatorial use of H2O2-induced fluorescence quenching of CdTe QDs as a fluorescence signal output and the ultrahigh catalytic activity of CAT to H2O2, our proposed method could be used to perform a dynamic linear detection of OTA ranging from 0.05 pg mL-1 to 10 pg mL-1. The half maximal inhibitory concentration was 0.53 pg mL-1 and the limit of detection was 0.05 pg mL-1. These values were approximately 283- and 300-folds lower than those of horseradish peroxidase (HRP)-based conventional ELISA, respectively. The reported method is accurate, highly reproducible, and specific against other mycotoxins in agricultural products as well. In summary, the developed fluorescence immunoassay based on H2O2-induced fluorescence quenching of CdTe QDs can be used for the rapid and highly sensitive detection of mycotoxins or haptens in food safety monitoring.Herein, for the first time we report an improved competitive fluorescent enzyme linked immunosorbent assay (ELISA) for the ultrasensitive detection of ochratoxin A (OTA) by using hydrogen peroxide (H2O2)-induced fluorescence quenching of mercaptopropionic acid-modified CdTe quantum dots (QDs). In this immunoassay, catalase (CAT) was labeled with OTA as a competitive antigen to connect the fluorescence signals of the QDs with the concentration of the target. Through the combinatorial use of H2O2-induced fluorescence quenching of CdTe QDs as a fluorescence signal output and the ultrahigh catalytic activity of CAT to H2O2, our proposed method could be used to perform a dynamic linear detection of OTA ranging from 0.05 pg mL-1 to 10 pg mL-1. The half maximal inhibitory concentration was 0.53 pg mL-1 and the limit of detection was 0.05 pg mL-1. These values were approximately 283- and 300-folds lower than those of horseradish peroxidase (HRP)-based conventional ELISA, respectively. The reported method is accurate, highly reproducible, and specific against other mycotoxins in agricultural products as well. In summary, the developed fluorescence immunoassay based on H2O2-induced fluorescence quenching of CdTe QDs can be used for the rapid and highly sensitive detection of mycotoxins or haptens in food safety monitoring. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01136e

Modified Nanodiamonds for Detoxification

NASA Astrophysics Data System (ADS)

Gibson, Natalie Marie

Nanodiamonds (NDs) are an emerging class of biomaterials that are reaching worldwide attention due to their biocompatible, nontoxic properties and abundant surface chemistries that lend them to a wide range of biomedical applications. Furthermore, surface functional groups of NDs can easily be tailored to exhibit desirable chemical, physical and biological properties. Such characteristics naturally allow for NDs' surface to be considered as ideal carriers for various molecules and biomolecules intended for the delivery or removal of molecules in vivo. NDs have already shown to have a high affinity for various biological molecules, including DNA and proteins. This dissertation, however, expands NDs' use to the adsorption of carcinogenic mycotoxins, aflatoxin B1 (AfB1) and ochratoxin A (OTA). It has been estimated that myocotoxins are found in approximately 25 % of the world's crops each year. Ingestion of mycotoxins contaminated crops has been linked to hepatocellular carcinoma, disease and death. Therefore, we aim to develop ND enterosorbents, for the binding and removal of mycotoxins within the gastrointestinal (GI) tract, thereby eliminating the effects of these toxins. While NDs are readily available, raw, unmodified NDs, like those typically received from vendors, possess inhomogeneous aggregate sizes and surface characteristics. Our research first explored several ND modification techniques to enhance ND's adsorption of AfB1 and OTA. Modification methods assessed in this research include size reduction techniques, plasma treatments, silane surface coatings and homogenous surface group termination, including carboxylation, hydrogenation and hydroxylation. The effectiveness of these NDs for mycotoxins removal was determined by calculations of maximum capacities and binding constants, as obtained through the Langmuir isotherm and related transform equations. Several of these treatments also showed heightening of the NDs' inherent zeta potentials (ZPs), which were essential for interacting with charged molecules, like OTA. Furthermore, the increased ZPs lead to improved colloidal stabilities over a wide range of pH, which is important for their interaction in the GI tract. While the dyes and OTA illustrated primarily electrostatic adsorption mechanisms, neutrally charged AfB1's adsorption was predominantly based upon the aggregate size of the ND substrate. In addition to mycotoxins, fluorescent dyes, including propidium iodide, pyranine and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), were initially utilized during methodological development. Fluorescent dye investigations helped assesses the adsorption mechanisms of NDs and demonstrated the significance of electrostatic interactions. Beyond electrostatic adsorption mechanisms, surface functional groups were also responsible for the amount of dye adsorbed, as was also true in OTA adsorption. Therefore, surface characterization was carried out for several ND samples by FTIR, TOF-SIMS and TDMS analysis. Final results of our studies show that our modified NDs perform better than yeast cells walls and other NDs but comparable to activated charcoal in the adsorption of AfB1, and outperform clay minerals in OTA studies. Moreover, it was demonstrated that adsorption can be maintained in a wide range of pH, thereby, increasing the possibility of NDs use in mycotoxins enterosorbent applications.

Health risk assessment of heavy metal variability in sachet water sold in Ado-Odo Ota, South-Western Nigeria.

PubMed

Emenike, PraiseGod Chidozie; Tenebe, Theophilus Imokhai; Omeje, Maxwell; Osinubi, Damilare Samuel

2017-08-31

The sales of sachet water (SW), also known as "pure water" (PW), in Nigeria is a lucrative business. It serves many people, especially low-income earners, by providing a more affordable access to safe drinking water when compared with table water. However, some of the producers of SW do not effectively treat raw water before packaging them for sale. This study investigates the presence and concentrations of heavy metals, such as chromium (Cr), iron (Fe), manganese (Mn), copper (Cu), aluminum (Al), and zinc (Zn) in some samples of SW sold within Ota, Ogun State, Nigeria. Samples of SW from nine different producers were purchased for four consecutive weeks and analyzed to determine the concentrations of these heavy metals in them. Furthermore, health risk indicators, such as chronic daily intake (CDI) and health risk indices (HRI) for children and adults, were calculated separately. The metal concentrations were compared with allowable limits set by the World Health Organization (WHO), Nigerian Industrial Standard (NIS), and the United States Environmental Protection Agency (US EPA). High concentrations of Cr, Fe, and Al were found in all the nine samples and exceeded the maximum allowable limits (MAL) of all the standards considered. However, the concentrations of Zn, Mn, and Cu were within permissible limits. The HRIs of heavy metals were in the order of Cu > Fe > Zn > Mn > Al > Cr, but since the standard limits set for some metals were exceeded, proper and effective treatment is required to safeguard the health of consumers.

Survey of Slaughtered Pigs for Occurrence of Ochratoxin A and Porcine Nephropathy in Serbia

PubMed Central

Milićević, Dragan; Jurić, Verica; Stefanović, Srđan; Jovanović, Milijan; Janković, Saša

2008-01-01

Samples of blood, kidney and liver were randomly selected from slaughtered pigs (n=90) and analyzed for ochratoxin A by HPLC. In addition, in order to obtain information on the occurrence of nephropathy, histological examinations were carried out. Of the 90 liver samples, 26.6% contained OTA in the range of 0.22–14.5 ng/g. The incidence of OTA in serum and kidney were very similar (31%, 33.3%), with a maximum concentration of 220.8 ng/mL, and 52.5 ng/g, respectively. Histopathological examination of kidneys confirmed tubulopathies with edema and cell vacuolization. In addition, hemorrhages and necrosis of proximal kidney tubules’ cells were found. PMID:19330066

Ultrasensitive electrochemical aptasensor for ochratoxin A based on two-level cascaded signal amplification strategy.

PubMed

Yang, Xingwang; Qian, Jing; Jiang, Ling; Yan, Yuting; Wang, Kan; Liu, Qian; Wang, Kun

2014-04-01

Ochratoxin A (OTA) has a number of toxic effects to both humans and animals, so developing sensitive detection method is of great importance. Herein, we describe an ultrasensitive electrochemical aptasensor for OTA based on the two-level cascaded signal amplification strategy with methylene blue (MB) as a redox indicator. In this method, capture DNA, aptamers, and reporter DNA functionalized-gold nanoparticles (GNPs) were immobilized on the electrode accordingly, where GNPs were used as the first-level signal enhancer. To receive the more sensitive response, a larger number of guanine (G)-rich DNA was bound to the GNPs' surface to provide abundant anchoring sites for MB to achieve the second-level signal amplification. By employing this novel strategy, an ~8.5 (±0.3) fold amplification in signal intensity was obtained. Afterward, OTA was added to force partial GNPs/G-rich DNA to release from the sensing interface and thus decreased the electrochemical response. An effective sensing range from 2.5pM to 2.5nM was received with an extremely low detection limit of 0.75 (±0.12) pM. This amplification strategy has the potential to be the main technology for aptamer-based electrochemical biosensor in a variety of fields. Copyright © 2013 Elsevier B.V. All rights reserved.

Mycotoxin food and feed regulation and the specific case of ochratoxin A: a review of the worldwide status.

PubMed

Duarte, S C; Lino, C M; Pena, A

2010-10-01

Mycotoxins are naturally occurring contaminants whose presence in food- and feedstuffs cannot be completely avoided. The safety and economic impact arising from the commercialization of mycotoxin-contaminated food and feed supply chain is considerable and acknowledged. To protect consumers from mycotoxin-derived health risks, many countries have adopted regulations or guidelines to limit exposure. Similar to regulation for other mycotoxins, the regulatory status of ochratoxin A (OTA) lacks consensus. Although this was one of the first fungal toxins to be subjected to compliance control due to its toxic properties, the conflict between the prime objective of consumer health safeguard and the economic interests of producers and traders remains. One of the key challenges facing policymakers is to balance these conflicting demands and reach consensual regulatory actions or limits. The noteworthy transboundary implications are recognized, both in the case of absence as the unsubstantiated tightening of regulatory limits. This paper scrutinizes the rationales and implications of mycotoxin regulation, with special attention devoted to OTA. In view of the ongoing debate concerning this complex issue, a review of the arguments and suggested strategies proposed by different parties is also made. The specific case of OTA regulation in food and feed is updated and analysed at a European Union and global level.

Determination of Ochratoxin A in wine by packed in-tube solid phase microextraction followed by high performance liquid chromatography coupled to tandem mass spectrometry.

PubMed

Andrade, Mariane A; Lanças, Fernando M

2017-04-14

Ochratoxin A (OTA), a widely studied mycotoxin, can be found in a variety of food matrices. As its concentration in food is generally low (in the order of μg kg -1 ), sample preparation techniques are necessary for the analyte purification and pre-concentration in order to achieve the required low detection limits. The separation and detection methods used for OTA analysis should also offer proper sensitivity in order to allow the adequate quantification of the analyte. This manuscript addresses the development of a methodology aiming the analysis of OTA in wine samples by packed in-tube SPME in flow through extraction mode coupled to HPLC-MS/MS. The in-tube SPME set up utilized a PEEK tube packed with C18 particles as the extraction column. The method was optimized by a central composite design 2 2 +3 extra central points, having as factors the percentage of ACN and time in the sample load step. The functionalities of the method were attested and its analytical conditions, enhanced by using 22% of ACN and 6min in the sample load step. Validation of the method was also accomplished prior to analyses of both dry red wine and dry white wine samples. The method demonstrated proper sensitivity, with detection and quantification limits equal to 0.02 and 0.05μgL -1 , respectively. Linearity and precision exhibited a 0.996 correlation coefficient and RSD under 6%, respectively. The method proved to be accurate at medium and higher concentration levels with a maximum recovery of 73% at higher concentration levels. OTA was not detected in either dry red and dry white wine samples evaluated in this work. If present, it would be at concentrations lower than the detection and quantification limits established for the proposed method, and considered not a potential danger to human health according to our present knowledge. Copyright © 2017 Elsevier B.V. All rights reserved.

Structural and Aerodynamic Optimization of UltraLightweight Technology for Research in Astronomy (ULTRA)

NASA Astrophysics Data System (ADS)

Etzel, P. B.; Martin, R.; Romeo, R.; Fesen, R.; Hale, R.; Taghavi, R.; Anthony-Twarog, B. J.; Shawl, S. J.; Twarog, B. A.

2004-12-01

The focus of ULTRA (see poster by Twarog et al.) is a three-year plan to develop and test ultralightweight technology for research applications in astronomy. The goal is to demonstrate that a viable alternative exists to traditional glass-mirror technology by designing, fabricating, and testing a research telescope prototype comprising fiber reinforced plastic (CFRP) materials. To date, several mirror designs have been tested. The main goal in the first year has been to develop a 0.4m diameter mirror and OTA that serve as prototypes for the 1m telescope design. Mirrors of 0.4m diameter have been successfully fabricated which yield diffraction limited images. This poster will include a display of the complete OTA (including optics), optics test results, and astronomical images taken with prototype mirrors. Finite element analysis has been used to evaluate the OTA and mirror designs. Preliminary design details were incorporated in a knowledge-based system. Adaptive Modeling Language (AML), an object oriented programming language developed by Technosoft, Inc., was used to develop a parameterized geometric model of the preliminary design. The system can generate mirrors with radials/circumferentials, tube core substructures, as well as modeling the support structure. Computational fluid dynamics analyses were performed for sweep, inclination and ambient wind speed. Finite element analyses were performed for core density and arrangement, skin thickness, back-surface curvature, spider configuration and arrangement of the OTA, while the loading conditions considered thus far are thermal, inertial, and aerodynamic pressure loads. Experimental tests, including ultrasonic nondestructive evaluations, infrared imaging, modal testing, and wind tunnel tests, have been performed on the first prototype mirror, with the primary goal of validating analytical models and identifying potential manufacturing induced variations to be expected among "like" mirrors. Support of this work by NSF grants AST-0320784 and AST-0321247, NASA grant NCC5-600, Kansas University, and San Diego State University is gratefully acknowledged

Successful and safe use of Q-switched lasers in the treatment of nevus of Ota in children with phototypes IV-VI.

PubMed

Belkin, Daniel A; Jeon, Hana; Weiss, Elliot; Brauer, Jeremy A; Geronemus, Roy G

2018-01-01

Nevus of Ota represents congenital dermal melanocytosis in a trigeminal distribution, most commonly occurring in Asian individuals and other individuals with skin of color. Evidence suggests early treatment is beneficial. Multiple reports have shown efficacy and safety of Q-switched laser treatment in adults. There is little data on children and in non-Asian skin types. This series was done to demonstrate safe and effective use of Q-switched laser therapy in children of multiple skin types. Retrospective case series. This was a chart review of patients under 18 years old who presented to our practice from 2002 to 2015 with a clinical diagnosis of nevus of Ota who were treated with Q-switched lasers (694 and 1,064 nm). Patients were treated without the use of general anesthesia or sedation, and corneal shields were used in appropriate cases. Percentage of improvement as well as side effects were rated by five physicians independently. Improvement, when present, was rated in quartiles (1-25%, 26-50%, 51-75%, and 76-100% improvement). Twenty-four children were included. The average age at the start of treatment was 3.9 years old (range of 3 months to 12.4 years), and patients had Fitzpatrick skin types IV through VI. The mean number of treatments was 9.3. Assessment revealed excellent response (76-100% improvement) in 70% of patients and good to excellent response (51-100% improvement) in 86%. Two patients (8%) had post-inflammatory hyperpigmentation, one of whom also had focal hypopigmentation. Treatment of nevus of Ota with Q-switched lasers in children with skin of color, without general anesthesia or sedation, is safe and effective. Early intervention should be encouraged for better efficacy and to prevent psychosocial distress in later childhood and adulthood. Lasers Surg. Med. 50:56-60, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

The development of an instrument to measure the self-efficacy of students participating in VEX robotics competitions

NASA Astrophysics Data System (ADS)

Robinson, Trevor P.

The number of robotics competitions has steadily increased over the past 30 years. Schools are implementing robotics competitions to increase student content knowledge and interest in science, technology, engineering, and mathematics (STEM). Companies in STEM-related fields are financially supporting robotics competitions to help increase the number of students pursuing careers in STEM among other reasons. These financial supporters and school administrations are asking what the outcomes of students participating in competitive robotics are. Few studies have been conducted to investigate these outcomes. The studies that have been conducted usually compare students in robotics to students not in robotics. There have not been any studies that compare students to themselves before and after participating in robotics competitions. This may be due to the lack of available instruments to measure student outcomes. This study developed an instrument to measure the self-efficacy of students participating in VEX Robotics Competitions (VRC). The VRC is the world's largest and fastest growing robotics competition available for middle and high school students. Self-efficacy was measured because of its importance to the education community. Students with higher self-efficacy tend to persevere through difficult tasks more frequently than students with low self-efficacy. A person's self-efficacy has major influence over what interests, activities, classes, college majors, and careers he or she will pursue in life. The self-efficacy survey instrument created through this study was developed through an occupational and task analysis (OTA), and initial content and face validity was established through the OTA process. Exploratory and confirmatory factor analyses were also conducted to assist in instrument validation. The reliability was calculated using Cronbach's alpha. Face validity was established through the OTA process. Construct validity was established through the factor analyses. The processes of the OTA and factor analyses have created an instrument that results indicate is reliable and valid to use in further research studies.

A self-assembly aptasensor based on thick-shell quantum dots for sensing of ochratoxin A

NASA Astrophysics Data System (ADS)

Chu, Xianfeng; Dou, Xiaowen; Liang, Ruizheng; Li, Menghua; Kong, Weijun; Yang, Xihui; Luo, Jiaoyang; Yang, Meihua; Zhao, Ming

2016-02-01

A novel self-assembling aptasensor was fabricated by precisely attaching three phosphorothioate-modified capture aptamers onto a single thick-shell quantum dot in a controllable manner for monitoring of ochratoxin A (OTA), a poisonous contaminant widespread in foodstuffs. Herein, CdSe/CdS QDs coated in ten layer CdS shells were synthesized using a continual precursor injection method. Analysis of the prepared CdSe/CdS QDs showed a zinc-blende structure, high photoluminescence quantum yields (>80%), and a photoemission peak with a narrow full-width at half-maximum (about 29 nm), all qualities that render them as a superior choice for optical applications. By adjusting the number of phosphorothioate bases in the anchor domain, the tunable-valency aptasensor was able to self-assemble. In the sensing strategy, the thick-shell quantum dot was provided as an acceptor while OTA itself was used as a donor. In the presence of OTA, the capture aptamers drive the aptasensor function into a measurable signal through a fluorescence resonance energy transfer (FRET) system. The newly developed aptasensor had a detection limit as low as 0.5 ng mL-1, with a linear concentration in the range of 1 to 30 ng mL-1, and therefore meets the requirements for rapid, effective, and anti-interference sensors for real-world applications. Moreover, the high quality thick-shell QDs provide an ideal alternative for highly sensitive imaging and intensive illumination in the fields of biotechnology and bioengineering.A novel self-assembling aptasensor was fabricated by precisely attaching three phosphorothioate-modified capture aptamers onto a single thick-shell quantum dot in a controllable manner for monitoring of ochratoxin A (OTA), a poisonous contaminant widespread in foodstuffs. Herein, CdSe/CdS QDs coated in ten layer CdS shells were synthesized using a continual precursor injection method. Analysis of the prepared CdSe/CdS QDs showed a zinc-blende structure, high photoluminescence quantum yields (>80%), and a photoemission peak with a narrow full-width at half-maximum (about 29 nm), all qualities that render them as a superior choice for optical applications. By adjusting the number of phosphorothioate bases in the anchor domain, the tunable-valency aptasensor was able to self-assemble. In the sensing strategy, the thick-shell quantum dot was provided as an acceptor while OTA itself was used as a donor. In the presence of OTA, the capture aptamers drive the aptasensor function into a measurable signal through a fluorescence resonance energy transfer (FRET) system. The newly developed aptasensor had a detection limit as low as 0.5 ng mL-1, with a linear concentration in the range of 1 to 30 ng mL-1, and therefore meets the requirements for rapid, effective, and anti-interference sensors for real-world applications. Moreover, the high quality thick-shell QDs provide an ideal alternative for highly sensitive imaging and intensive illumination in the fields of biotechnology and bioengineering. Electronic supplementary information (ESI) available: Table S1. See DOI: 10.1039/c5nr08284f

Mechanisms of Mycotoxin-Induced Neurotoxicity through Oxidative Stress-Associated Pathways

PubMed Central

Doi, Kunio; Uetsuka, Koji

2011-01-01

Among many mycotoxins, T-2 toxin, macrocyclic trichothecenes, fumonisin B1 (FB1) and ochratochin A (OTA) are known to have the potential to induce neurotoxicity in rodent models. T-2 toxin induces neuronal cell apoptosis in the fetal and adult brain. Macrocyclic trichothecenes bring about neuronal cell apoptosis and inflammation in the olfactory epithelium and olfactory bulb. FB1 induces neuronal degeneration in the cerebral cortex, concurrent with disruption of de novo ceramide synthesis. OTA causes acute depletion of striatal dopamine and its metabolites, accompanying evidence of neuronal cell apoptosis in the substantia nigra, striatum and hippocampus. This paper reviews the mechanisms of neurotoxicity induced by these mycotoxins especially from the viewpoint of oxidative stress-associated pathways. PMID:21954354

Early Tibiotalocalcaneal Arthrodesis Intramedullary Nail for Treatment of a Complex Tibial Pilon Fracture (AO/OTA 43-C).

PubMed

Hsu, Andrew R; Szatkowski, Jan P

2015-06-01

Management of severely comminuted, complete articular tibial pilon fractures (AO/OTA 43-C) remains a challenge, with few treatment options providing good clinical outcomes. Open reduction and internal fixation of the tibial plafond, tibiotalar arthrodesis, and salvage hindfoot reconstruction procedures are all associated with surgical complications and functional limitations. In this report, we present a case of a complex pilon fracture in a patient with multiple medical comorbidities and socioeconomic disadvantages that was successfully and acutely treated with a retrograde tibiotalocalcaneal hindfoot arthrodesis nail. At final follow-up examination, the patient had decreased pain, a stable plantigrade foot, and could ambulate with normal shoes without any assistive devices. Therapeutic, Level IV: Case series. © 2014 The Author(s).

Cleaning up contaminated wood-treating sites. Background paper

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

This report identifies technologies available for organic hazardous waste cleanup at woodtreating sites throughout the country. OTA has identified a range of such technologies that have been selected in the past and could be applied to other sites in the future. The applicability of a technology to a particular Superfund site has to be based on many site-specific factors. Nevertheless, it is clear that a number of the approaches identified by OTA may be appropriate and could prove useful if more detailed site-specific studies and tests were done. Although this study focused on the Texarkana site, decisionmakers and the publicmore » could benefit from this analysis in selecting future cleanup strategies for other sites.« less

Development of the custom polymeric materials specific for aflatoxin B1 and ochratoxin A for application with the ToxiQuant T1 sensor tool.

PubMed

Piletska, Elena; Karim, Kal; Coker, Raymond; Piletsky, Sergey

2010-04-16

Two polymers were computationally designed with affinity to two of the most abundant mycotoxins aflatoxin B1 (AFB1) and ochratoxin A (OTA) for application in the ToxiQuant T1 System. The principle of quantification of AFB1 and OTA using the ToxiQuant T1 instrument comprised of a fluorimetric analysis of mycotoxins adsorbed on the polymer upon exposure to UV light. High affinity of the developed resins allowed the adsorption of both toxins as discrete bands on the top of the cartridge with detection limit as low as 1ng quantity of mycotoxins. Copyright 2009 Elsevier B.V. All rights reserved.

Year to year variation of rainfall rate and rainfall regime in Ota, southwest Nigeria for the year 2012 to 2015

NASA Astrophysics Data System (ADS)

Omotosho, T. V.; Ometan, O. O.; Akinwumi, S. A.; Adewusi, O. M.; Boyo, A. O.; Singh, M. S. J.

2017-05-01

The tropics is characterized to have convective type of rainfall which has high occurrence of rainfall compared to the temperate regions of the world. In this paper, the accumulation of rainfall in Ota, Southwest, Nigeria (6° 42 N, 3° 14 E) has been analysed to present the one-minute rainfall rate and the predominant type of rainfall. Four years’ data used for this study was taken using the Davis Wireless vantage Pro2 weather station at Covenant University, Ota, Ogun State. The data collected were used to analyse the one-minute rainfall rate and different types of rainfall predominant in this region. For the prediction and modelling of rain attenuation at microwave frequencies for a region like the Nigeria at various percentage of time, one-minute rainfall rate is required. Nigeria falls into the P zone of 114 mm/hr. as per International Telecommunication Union - Recommendation (ITU-R). The analysis carried out indicated that the measured yearly averaged maximum one-minute rainfall rate for 2012, 2013, 2014 and 2015 are 157.7 mm/h, 148.0 mm/h, 241.2 mm/h and 157.3 mm/h respectively. It also indicated that the drizzle type of rainfall is predominant in contrast to established fact that thunderstorm occurs more in the tropics.

Early detection of Aspergillus carbonarius and A. niger on table grapes: a tool for quality improvement.

PubMed

Ayoub, F; Reverberi, M; Ricelli, A; D'Onghia, A M; Yaseen, T

2010-09-01

Aspergillus carbonarius and A. niger aggregate are the main fungal contaminants of table grapes. Besides their ability to cause black rot, they can produce ochratoxin A (OTA), a mycotoxin that has attracted increasing attention worldwide. The objective of this work was to set up a simple and rapid molecular method for the early detection of both fungi in table grapes before fungal development becomes evident. Polymerase chain reaction (PCR)-based assays were developed by designing species-specific primers based on the polyketide synthases (PKS(S)) sequences of A. carbonarius and A. niger that have recently been demonstrated to be involved in OTA biosynthesis. Three table grape varieties (Red globe, Crimson seedless, and Italia) were inoculated with A. carbonarius and A. niger aggregate strains producing OTA. The extracted DNA from control (non-inoculated) and inoculated grapes was amplified by PCR using ACPKS2F-ACPKS2R for A. carbonarius and ANPKS5-ANPKS6 for A. niger aggregate. Both primers allowed a clear detection, even in symptomless samples. PCR-based methods are considered to be a good alternative to traditional diagnostic means for the early detection of fungi in complex matrix for their high specificity and sensitivity. The results obtained could be useful for the definition of a 'quality label' for tested grapes to improve the safety measures taken to guarantee the production of fresh table grapes.

Facile synthesis of Fe3O4/g-C3N4/HKUST-1 composites as a novel biosensor platform for ochratoxin A.

PubMed

Hu, Shuisheng; Ouyang, Wenjun; Guo, Longhua; Lin, Zhenyu; Jiang, Xiaohua; Qiu, Bin; Chen, Guonan

2017-06-15

A fluorescent biosensor for ochratoxin A was fabricated on the basis of a new nanocomposite (Fe 3 O 4 /g-C 3 N 4 /HKUST-1 composites). Fe 3 O 4 /g-C 3 N 4 /HKUST-1 was synthesized in this work for the first time, which combined HKUST-1 with g-C 3 N 4 to improve its chemical stability. Fe 3 O 4 /g-C 3 N 4 /HKUST-1 composites have strong adsorption capacity for dye-labeled aptamer and are able to completely quench the fluorescence of the dye through the photoinduced electron transfer (PET) mechanism. In the presence of ochratoxin A (OTA), it can bind with the aptamer with high affinity, causing the releasing of the dye-labeled aptamer from the Fe 3 O 4 /g-C 3 N 4 /HKUST-1 and therefore results in the recovery of fluorescence. The fluorescence intensity of the biosensor has a linear relationship with the OTA concentration in the range of 5.0-160.0ng/mL. The LOD of sensor is 2.57ng/mL (S/N=3). This fluorescence sensor based on the Fe 3 O 4 /g-C 3 N 4 /HKUST-1 composites has been applied to detect OTA in corn with satisfying results. Copyright © 2016. Published by Elsevier B.V.

Impact of maximum levels in European legislation on exposure of mycotoxins in dried products: case of aflatoxin B1 and ochratoxin A in nuts and dried fruits.

PubMed

Van de Perre, Evelien; Jacxsens, Liesbeth; Lachat, Carl; El Tahan, Fouad; De Meulenaer, Bruno

2015-01-01

In this study the impact of setting European criteria on exposure to aflatoxin B1 via nuts and figs and ochratoxin A via dried fruits is evaluated for the Belgian population, as an example of the European population. Two different scenarios were evaluated. In scenario 1 all collected literature data are considered, assuming that there is no border control nor legal limits in Europe. In the second scenario, contamination levels above the maximum limits are excluded. The results from scenario 1 demonstrated that if no regulation is in place, AFB1 and OTA concentrations reported in the analysed food can have potential health risk to the population. The estimated exposure of OTA for scenario 2 is below the TDI of 5 ng/kg BW⋅day, indicating that OTA concentrations accepted by EU legislation pose a low risk to the Belgian population. For AFB1, the MOE values of scenario 2 are above 10,000 and can be considered to be of low health concern, based on BDML10 for humans, except for figs (MOE = 5782). This means that for all matrices, with exception of figs, the maximum values of AFB1 in the European legislation are sufficient to be of a low health concern for consumers. Copyright © 2014. Published by Elsevier Ltd.

HabEx Optical Telescope Assembly

NASA Technical Reports Server (NTRS)

Stahl, H. Philip

2017-01-01

Purpose: a) Introduce candidate optical telescope assembly (OTA) architectures. b) Illustrate design/analysis process. Agenda: a) Definitions, Specification & Assumptions. b.) 4-meter Monolithic Mirror Concept. c) 6.5-meter Segmented Mirror Concept.

Transportation of hazardous materials

DOT National Transportation Integrated Search

1986-07-01

This report discusses transportation of all hazardous materials (commodities, : radioactive materials including spent nuclear fuel, and hazardous wastes) that : travel by truck, rail, water, or air. The Office of Technology Assessment (OTA) : has ide...

Complications of volar locking plating of distal radius fractures in 576 patients with 3.2 years follow-up.

PubMed

Thorninger, Rikke; Madsen, Mette Lund; Wæver, Daniel; Borris, Lars Carl; Rölfing, Jan Hendrik Duedal

2017-06-01

Volar plating of unstable distal radius fractures (DRF) has become the favoured treatment. The complication rates vary from 3 to 36%. The purpose of the study was to estimate the complication rate of volar plating of DRF and its association with AO/OTA fracture type, surgeon experience and type of volar plate. Retrospectively, all patients treated with volar plating of a DRF between February 2009 and June 2013 at Aarhus University Hospital, Denmark were included. AO/OTA fracture type, surgeon experience (1st year, 2nd-5th year resident or consultant), type of plate (VariAx ® , Acu-Loc ® ) and complications were extracted from the electronic medical records. Complications were categorized as carpal tunnel syndrome, other sensibility issues, tendon complications including irritation and rupture, deep infections, complex regional pain syndrome and unidentified DRUJ or scapholunar problems. Reoperations including hardware removal were also charted. 576 patients with a median age of 63 years (min: 15; max: 87) were included. 78% were female and the mean observation time was 3.2 years (min: 2.0; max: 5.4). 78% (n=451) of the patients were treated with VariAx ® and 22% (n=125) with Acu-Loc ® . The overall complication rate was 14.6% (95% CI 11.8-17.7) including carpal tunnel syndrome or change in sensibility in 5.2% and tendon complications in 4.7%. Five flexor tendon ruptures and 12 extensor tendon ruptures were observed. The reoperation rate was 10.4% including 41 cases of hardware removal. A statistically significant association between AO/OTA fracture type C and complications was found. No statistically significant association between complication rate and surgeon experience and type of plate was observed. The majority of DRF patients treated with a volar plate suffer no complications. However, the overall complication rate of 14.6% is substantial. Intra-articular fractures, e.g. AO/OTA-type 23C1-3, had significantly higher complication rates. Neither surgeon experience, nor type of volar plate was able to predict complications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ipsilateral intact fibula as a predictor of tibial plafond fracture pattern and severity.

PubMed

Luk, Pamela C; Charlton, Timothy P; Lee, Jackson; Thordarson, David B

2013-10-01

The objective of this study was to determine whether there is a difference in fracture pattern and severity of comminution between tibial plafond fractures with and without associated fibular fractures using computed tomography (CT). We hypothesized that the presence of an intact fibula was predictive of increased tibial plafond fracture severity. This was a case control, radiographic review performed at a single level I university trauma center. Between November 2007 and July 2011, 104 patients with 107 operatively treated tibial pilon fractures and preoperative CT scans were identified: 70 patients with 71 tibial plafond fractures had associated fibular fractures, and 34 patients with 36 tibial plafond fractures had intact fibulas. Four criteria were compared between the 2 groups: AO/OTA classification of distal tibia fractures, Topliss coronal and sagittal fracture pattern classification, plafond region of greatest comminution, and degree of proximal extension of fracture line. The intact fibula group had greater percentages of AO/OTA classification B2 type (5.5 vs 0, P = .046) and B3 type (52.8 vs 28.2, P = .013). Conversely, the percentage of AO/OTA classification C3 type was greater in the fractured fibula group (53.5 vs 30.6, P = .025). Evaluation using the Topliss sagittal and coronal classifications revealed no difference between the 2 groups (P = .226). Central and lateral regions of the plafond were the most common areas of comminution in fractured fibula pilons (32% and 31%, respectively). The lateral region of the plafond was the most common area of comminution in intact fibula pilon fractures (42%). There was no statistically significant difference (P = .71) in degree of proximal extension of fracture line between the 2 groups. Tibial plafond fractures with intact fibulas were more commonly associated with AO/OTA classification B-type patterns, whereas those with fractured fibulas were more commonly associated with C-type patterns. An intact fibula may be predictive of less comminution of the plafond. The lateral and central regions of the plafond were the most common areas of comminution in tibial plafond fractures, regardless of fibular status. Level III, case control study.

OTA director to be Clinton's science advisor

NASA Astrophysics Data System (ADS)

Leath, Audrey

President Clinton has nominated John H. “Jack” Gibbons to be Assistant to the President for Science and Technology, and director of the White House Office of Science and Technology Policy (OSTP). For over a decade, Gibbons has served as director of the Office of Technology Assessment (OTA), a bipartisan research arm of Congress.In nominating Gibbons, Clinton said, “I am delighted to appoint a brilliant scientist and gifted administrator… It is profoundly important that the president have a science advisor who understands science, who understands technology, who understands the practical application of these disciplines to the myriad of problems we face today. And I can tell you that from [Vice-president] Al Gore on down to every other member of Congress I have discussed John Gibbons with, I have hardly ever received more glowing and more consistent recommendations for anyone.”

Exceptionally Long-Lived Charge Separated State in Zeolitic Imidazolate Framework: Implication for Photocatalytic Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pattengale, Brian; Yang, Sizhuo; Ludwig, John

2016-06-22

Zeolitic Imidazolate Frameworks (ZIFs) have emerged as a novel class of porous metal-organic frameworks (MOFs) for catalysis application because of their exceptional thermal and chemical stability. Inspired by the broad absorption of ZIF-67 in UV-visible-near IR region, we explored its excited state and charge separation dynamics, properties essential for photocatalytic applications, using optical (OTA) and X-ray transient absorption (XTA) spectroscopy. OTA results show that an exceptionally long-lived excited state is formed after photoexcitation. This long-lived excited state was confirmed to be the charge separated state with ligandto-metal charge transfer character using XTA. The surprisingly long-lived charge separated state, together withmore » its intrinsic hybrid nature, all point to its potential application in heterogeneous photocatalysis and energy conversion.« less

Lack of an Apparent Association between Mycotoxin Concentrations in Red Chili Peppers and Incidence of Gallbladder Cancer in India : an Ecological Study.

PubMed

Ikoma, Toshikazu; Kapoor, Vinay Kumar; Behari, Anu; Mishra, Kumudesh; Tsuchiya, Yasuo; Asai, Takao; Endoh, Kazuo; Okano, Kiyoshi; Nakamura, Kazutoshi

2016-01-01

Our recent studies conducted in South America have shown that mycotoxin contamination of red chili peppers (RCPs) may be associated with an increased risk of gallbladder cancer (GBC). Whether this relationship exists in India, a country with a high incidence of GBC and high consumption of RCPs, is unclear. We therefore measured concentrations of aflatoxins (AFs) and ochratoxin A (OTA) in RCPs from areas of low, medium, and high incidence of GBC in India, and compared these concentrations with GBC incidence in each area. Twentyone RCP samples were collected from nine cities (eight from a lowincidence area, five from a mediumincidence area, and eight from a highincidence area). Concentrations of AFs and OTA were measured using highperformance liquid chromatography. No significant differences in mean concentrations of AFs and OTA were found in the three areas. AFB1 levels in the lowincidence area (10.81 ?g/kg) and highincidence area (12.00 ?g/kg) were more than 2.2 and 2.4 times higher compared with the maximum permitted level of AFB1 in spices (5.0 ?g/kg) set by the Commission of the European Communities, or that (4.4 ?g/kg) obtained in our previous study in Chile. Our results show that the mean concentrations of mycotoxins in RCPs are similar among the three areas in India with different incidences of GBC. Further studies with human subjects are needed to evaluate any association between AFB1 and GBC.

Construction of fiber-shaped silver oxide/tantalum nitride p-n heterojunctions as highly efficient visible-light-driven photocatalysts.

PubMed

Li, Shijie; Hu, Shiwei; Xu, Kaibing; Jiang, Wei; Liu, Yu; Leng, Zhe; Liu, Jianshe

2017-10-15

Constructing novel and efficient p-n heterojunction photocatalysts has stimulated great interest. Herein, we report the design and synthesis of fiber-shaped Ag 2 O/Ta 3 N 5 p-n heterojunctions as a kind of efficient photocatalysts. Ta 3 N 5 nanofibers were prepared by an electrospinning-calcination-nitridation method, and then the in-situ anchoring of Ag 2 O on their surfaces was realized by a facile deposition method. The resulting Ag 2 O/Ta 3 N 5 heterojunctions were comprised of porous Ta 3 N 5 nanofibers (diameter: ∼150nm) and Ag 2 O nanoparticles (size: ∼12nm). The photocatalytic activity of these heterojunctions were studied by decomposing rhodamine B (RhB) dye and tetracycline (TC) antibiotic under visible light (λ>400nm). In all the samples, the heterojunction with Ag 2 O/Ta 3 N 5 molar ratio of 0.2/1 displays the best activity. It is found that a synergistic effect contributes to the effective suppression of charges recombination between Ta 3 N 5 and Ag 2 O, leading to an enhanced photocatalytic activity with good stability. The photogenerated holes (h + ) and superoxide radicals (O 2 - ) play dominant roles in the photocatalytic process. These p-n heterojunctions will have great potential for environmental remediation because of the facile preparation process and exceptional photocatalytic activity. Copyright © 2017 Elsevier Inc. All rights reserved.

CMOS image sensor with contour enhancement

NASA Astrophysics Data System (ADS)

Meng, Liya; Lai, Xiaofeng; Chen, Kun; Yuan, Xianghui

2010-10-01

Imitating the signal acquisition and processing of vertebrate retina, a CMOS image sensor with bionic pre-processing circuit is designed. Integration of signal-process circuit on-chip can reduce the requirement of bandwidth and precision of the subsequent interface circuit, and simplify the design of the computer-vision system. This signal pre-processing circuit consists of adaptive photoreceptor, spatial filtering resistive network and Op-Amp calculation circuit. The adaptive photoreceptor unit with a dynamic range of approximately 100 dB has a good self-adaptability for the transient changes in light intensity instead of intensity level itself. Spatial low-pass filtering resistive network used to mimic the function of horizontal cell, is composed of the horizontal resistor (HRES) circuit and OTA (Operational Transconductance Amplifier) circuit. HRES circuit, imitating dendrite of the neuron cell, comprises of two series MOS transistors operated in weak inversion region. Appending two diode-connected n-channel transistors to a simple transconductance amplifier forms the OTA Op-Amp circuit, which provides stable bias voltage for the gate of MOS transistors in HRES circuit, while serves as an OTA voltage follower to provide input voltage for the network nodes. The Op-Amp calculation circuit with a simple two-stage Op-Amp achieves the image contour enhancing. By adjusting the bias voltage of the resistive network, the smoothing effect can be tuned to change the effect of image's contour enhancement. Simulations of cell circuit and 16×16 2D circuit array are implemented using CSMC 0.5μm DPTM CMOS process.

Multiplexed detection of mycotoxins in foods with a regenerable array.

PubMed

Ngundi, Miriam M; Shriver-Lake, Lisa C; Moore, Martin H; Ligler, Frances S; Taitt, Chris R

2006-12-01

The occurrence of different mycotoxins in cereal products calls for the development of a rapid, sensitive, and reliable detection method that is capable of analyzing samples for multiple toxins simultaneously. In this study, we report the development and application of a multiplexed competitive assay for the simultaneous detection of ochratoxin A (OTA) and deoxynivalenol (DON) in spiked barley, cornmeal, and wheat, as well as in naturally contaminated maize samples. Fluoroimmunoassays were performed with the Naval Research Laboratory array biosensor, by both a manual and an automated version of the system. This system employs evanescent-wave fluorescence excitation to probe binding events as they occur on the surface of a waveguide. Methanolic extracts of the samples were diluted threefold with buffer containing a mixture of fluorescent antibodies and were then passed over the arrays of mycotoxins immobilized on a waveguide. Fluorescent signals of the surface-bound antibody-antigen complexes decreased with increasing concentrations of free mycotoxins in the extract. After sample analysis was completed, surfaces were regenerated with 6 M guanidine hydrochloride in 50 mM glycine, pH 2.0. The limits of detection determined by the manual biosensor system were as follows: 1, 180, and 65 ng/g for DON and 1, 60, and 85 ng/g for OTA in cornmeal, wheat, and barley, respectively. The limits of detection in cornmeal determined with the automated array biosensor were 15 and 150 ng/g for OTA and DON, respectively.

A fully automated method for simultaneous determination of aflatoxins and ochratoxin A in dried fruits by pressurized liquid extraction and online solid-phase extraction cleanup coupled to ultra-high-pressure liquid chromatography-tandem mass spectrometry.

PubMed

Campone, Luca; Piccinelli, Anna Lisa; Celano, Rita; Russo, Mariateresa; Valdés, Alberto; Ibáñez, Clara; Rastrelli, Luca

2015-04-01

According to current demands and future perspectives in food safety, this study reports a fast and fully automated analytical method for the simultaneous analysis of the mycotoxins with high toxicity and wide spread, aflatoxins (AFs) and ochratoxin A (OTA) in dried fruits, a high-risk foodstuff. The method is based on pressurized liquid extraction (PLE), with aqueous methanol (30%) at 110 °C, of the slurried dried fruit and online solid-phase extraction (online SPE) cleanup of the PLE extracts with a C18 cartridge. The purified sample was directly analysed by ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for sensitive and selective determination of AFs and OTA. The proposed analytical procedure was validated for different dried fruits (vine fruit, fig and apricot), providing method detection and quantification limits much lower than the AFs and OTA maximum levels imposed by EU regulation in dried fruit for direct human consumption. Also, recoveries (83-103%) and repeatability (RSD < 8, n = 3) meet the performance criteria required by EU regulation for the determination of the levels of mycotoxins in foodstuffs. The main advantage of the proposed method is full automation of the whole analytical procedure that reduces the time and cost of the analysis, sample manipulation and solvent consumption, enabling high-throughput analysis and highly accurate and precise results.

Railroad safety : U.S.-Canadian comparison

DOT National Transportation Integrated Search

1979-08-01

In June 1978, Congress requested the Office of Technology Assessment (OTA) to : conduct "a detailed comparison between conditions prevailing in railway safety : in the United States and a review of safety operations in Canada. " Responding : to this ...

Levels of fungi and mycotoxins in the samples of grain and grain dust collected from five various cereal crops in eastern Poland.

PubMed

Krysińska-Traczyk, Ewa; Perkowski, Juliusz; Dutkiewicz, Jacek

2007-01-01

During combine harvesting of 5 various cereal crops (rye, barley, oats, buckwheat, corn) 24 samples of grain and 24 samples of settled grain dust were collected on farms located in the Lublin province of eastern Poland. The samples were examined for the concentration of total microfungi, Fusarium species, deoxynivalenol (DON), nivalenol (NIV), and ochratoxin A (OTA). Microfungi able to grow on malt agar were present in 79.2% of grain samples and in 91.7% of grain dust samples in the concentrations of 1.0-801.3x10(3) cfu/g and 1.5-12440.0x10(3) cfu/g, respectively. The concentration of microfungi in grain dust samples was significantly greater than in grain samples (p<0.01). Fusarium strains were isolated from 54.2% of grain samples and from 58.3% of grain dust samples in the concentrations of 0.1-375.0x10(3) cfu/g and 4.0-7,700.0x10(3) cfu/g, respectively. They were found in all samples of grain and grain dust from rye, barley and corn, but only in 0-16.7% of samples of grain and grain dust from oats and buckwheat. DON was found in 79.2% of grain samples and in 100% of grain dust samples in the concentrations of 0.001-0.18 microg/g and 0.006-0.283 microg/g, respectively. NIV was detected in 62.5% of grain samples and in 94.4% of grain dust samples in the concentrations of 0.004-0.502 microg/g and 0.005-0.339 microg/g, respectively. OTA was detected in 58.3% of grain samples and in 91.7% of grain dust samples in the concentrations of 0.00039- 0.00195 microg/g and 0.00036-0.00285 microg/g, respectively. The concentrations of DON, total fusariotoxins (DON+NIV) and OTA were significantly greater in grain dust samples than in grain samples (p<0.05, p<0.05, and p<0.001, respectively). The concentration of Fusarium poae in the samples of rye grain and dust was significantly correlated with the concentrations of DON (p<0.05), NIV (p<0.01), and total fusariotoxins (p<0.05). Similarly, the concentration of Fusarium culmorum in the samples of barley grain and dust was significantly correlated with the concentration of total fusariotoxins (p<0.05). A significant correlation was also found between the concentration of total fungi grown on malt agar and the concentration of OTA (p<0.05). In conclusion, although the concentration of DON, NIV and OTA in the samples of grain dust collected from 5 various cereals on farms in eastern Poland was not large, the persistent presence of these mycotoxins in over 90% of examined samples poses a potential health risk of chronic respiratory intoxication for exposed grain farmers.

Selected Technical and Economic Comparisons of Synfuel Options

DOT National Transportation Integrated Search

1981-04-01

This study is a comparative technical and economic assessment of selected synfuel technologies. It contains papers written for Office of Technology Assessment (OTA) to assist in preparation of the report "Increased Automobile Fuel Efficiency and Synt...

Application of upconversion luminescent-magnetic microbeads with weak background noise and facile separation in ochratoxin A detection

NASA Astrophysics Data System (ADS)

Liao, Zhenyu; Zhang, Ying; Su, Lin; Chang, Jin; Wang, Hanjie

2017-02-01

Ochratoxin A (OTA), the most harmful and abundant ochratoxin, is chemically stable and commonly existed in foodstuffs. In this work, upconversion luminescent-magnetic microbeads (UCLMMs) -based cytometric bead array for OTA detection with a less reagent consumption and high sensitivity has been established and optimized. In UCLMMs, upconversion nanocrystals (UCNs) for optical code present a weak background noise and no spectral cross talk between the encoding signals and target labels under two excitation conditions to improve detection sensitivity. While the superparamagnetic Fe3O4 nanoparticles (Fe3O4 NPs) aim for rapid analysis. The results show that the developed method has a sensitivity of 9.553 ppt below HPLC with a 50-μL sample and can be completed in <2 h with good accuracy and high reproducibility. Therefore, different colors of UCLMMs will become a promising assay platform for multiple mycotoxins after further improvement.

Third-Order Elliptic Lowpass Filter for Multi-Standard Baseband Chain Using Highly Linear Digitally Programmable OTA

NASA Astrophysics Data System (ADS)

Elamien, Mohamed B.; Mahmoud, Soliman A.

2018-03-01

In this paper, a third-order elliptic lowpass filter is designed using highly linear digital programmable balanced OTA. The filter exhibits a cutoff frequency tuning range from 2.2 MHz to 7.1 MHz, thus, it covers W-CDMA, UMTS, and DVB-H standards. The programmability concept in the filter is achieved by using digitally programmable operational transconductors amplifier (DPOTA). The DPOTA employs three linearization techniques which are the source degeneration, double differential pair and the adaptive biasing. Two current division networks (CDNs) are used to control the value of the transconductance. For the DPOTA, the third-order harmonic distortion (HD3) remains below -65 dB up to 0.4 V differential input voltage at 1.2 V supply voltage. The DPOTA and the filter are designed and simulated in 90 nm CMOS technology with LTspice simulator.

Polyphasic approach for differentiating Penicillium nordicum from Penicillium verrucosum.

PubMed

Berni, E; Degola, F; Cacchioli, C; Restivo, F M; Spotti, E

2011-04-01

The aim of this research was to use a polyphasic approach to differentiate Penicillium verrucosum from Penicillium nordicum, to compare different techniques, and to select the most suitable for industrial use. In particular, (1) a cultural technique with two substrates selective for these species; (2) a molecular diagnostic test recently set up and a RAPD procedure derived from this assay; (3) an RP-HPLC analysis to quantify ochratoxin A (OTA) production and (4) an automated system based on fungal carbon source utilisation (Biolog Microstation™) were used. Thirty strains isolated from meat products and originally identified as P. verrucosum by morphological methods were re-examined by newer cultural tests and by PCR methods. All were found to belong to P. nordicum. Their biochemical and chemical characterisation supported the results obtained by cultural and molecular techniques and showed the varied ability in P. verrucosum and P. nordicum to metabolise carbon-based sources and to produce OTA at different concentrations, respectively.

A pseudo differential Gm—C complex filter with frequency tuning for IEEE802.15.4 applications

NASA Astrophysics Data System (ADS)

Xin, Cheng; Lungui, Zhong; Haigang, Yang; Fei, Liu; Tongqiang, Gao

2011-07-01

This paper presents a CMOS Gm—C complex filter for a low-IF receiver of the IEEE 802.15.4 standard. A pseudo differential OTA with reconfigurable common mode feedback and common mode feed-forward is proposed as well as the frequency tuning method based on a relaxation oscillator. A detailed analysis of non-ideality of the OTA and the frequency tuning method is elaborated. The analysis and measurement results have shown that the center frequency of the complex filter could be tuned accurately. The chip was fabricated in a standard 0.35 μm CMOS process, with a single 3.3 V power supply. The filter consumes 2.1mA current, has a measured in-band group delay ripple of less than 0.16 μs and an IRR larger than 28 dB at 2 MHz apart, which could meet the requirements oftheIEEE802.15.4 standard.

Comparison of In-Solution Biorecognition Properties of Aptamers against Ochratoxin A

PubMed Central

McKeague, Maureen; Velu, Ranganathan; De Girolamo, Annalisa; Valenzano, Stefania; Pascale, Michelangelo; Smith, McKenzie; DeRosa, Maria C.

2016-01-01

Ochratoxin A (OTA) is a mycotoxin produced as a secondary metabolite by several species of Aspergillus and Penicillium and frequently found as a natural contaminant in a wide range of food commodities. Novel and robust biorecognition agents for detecting this molecule are required. Aptamers are artificial nucleic acid ligands able to bind with high affinity and specificity to a given target molecule. In the last few years, three separate research groups have selected aptamers for ochratoxin A. While each of these three families of aptamers have been incorporated into various methods for detecting OTA, it is unclear if each aptamer candidate is better suited for a particular application. Here, we perform the first head-to-head comparison of solution-based binding parameters for these groups of aptamers. Based on our results, we provide recommendations for the appropriate choice of aptamer for incorporation into solution-based biorecognition assays and applications. PMID:27854269

Natural occurrence of ochratoxin A in wolfberry fruit wine marketed in China.

PubMed

Kuang, Ying; Qiu, Feng; Kong, Weijun; Yang, Meihua

2012-01-01

Wolfberry fruit wine (WFW) is widely used as a global functional food to improve the immune system and prevent human disease. A total of 36 bottled WFWs were randomly collected in China between 2005 and 2010. Samples were analysed for the presence of ochratoxin A (OTA) using immunoaffinity column (IAC) clean-up and high-performance liquid chromatography with fluorescence detection (HPLC-FLD). Positive results were confirmed by liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS/MS). The limit of detection (LOD), based on a signal-to-noise ratio of 3, was 0.05 ng mL⁻¹. Recoveries ranged from 78.3% to 94.7% and relative standard deviations from 1.1% to 4.3% within the spiking range of 0.2-20 ng mL⁻¹. OTA was detected in one sample, below the maximum allowable limit as established by the European community.

Label-free impedimetric immunosensor for sensitive detection of ochratoxin A.

PubMed

Radi, Abd-Elgawad; Muñoz-Berbel, Xavier; Lates, Vasilica; Marty, Jean-Louis

2009-03-15

A novel label-free electrochemical impedimetric immunosensor for sensitive detection of ochratoxin A (OTA) was reported. A two-step reaction protocol was elaborated to modify the gold electrode. The electrode was first derivatized by electrochemical reduction of in situ generated 4-carboxyphenyl diazonium salt (4-CPDS) in acidic aqueous solution yielded stable 4-carboxyphenyl (4-CP) monolayer. The ochratoxin A antibody was then immobilized making use of the carbodiimide chemistry. The steps of the immunosensor elaboration and the immunochemical reaction between ochratoxin A and the surface-bound antibody were interrogated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The impedance change, due to the specific immuno-interaction at the immunosensor surface was utilized to detect ochratoxin A. The increase in electron-transfer resistance (DeltaR(et)) values was linearly proportional to the concentration of OTA in the range of 1-20ngmL(-1), with a detection limit of 0.5ngmL(-1).

Measurements of slope current and environmental geochemistry near the western boundary of the Gulf of the Farallones National Marine Sanctuary

USGS Publications Warehouse

Noble, Marlene A.; Xu, Jingping; Kolak, Jon; Gartner, Anne L.; Rosenberger, Kurt J.

2007-01-01

For nearly a decade, dredged material from San Francisco Bay has been deposited at the U.S. Environmental Protection Agency (EPA) Region IX designated disposal site on the continental slope west of the Farallon Islands. Over the past several years, annual disposal volumes have ranged from 136,170 m3 (61 barge loads) to 2,407,600 m3 (1,173 barge loads) (Ota, personal communication, 2000). The EPA has conducted extensive studies to evaluate the fate and effects of the disposed material (Abdelrhman, 1992; Tetra-Tech, 1992; SAIC, 1992). The EPA has also maintained a long-term monitoring program to collect hydrodynamic, sedimentary, chemical, and biological data that are used to determine whether the dredged material adversely affects the ecology of adjacent water bodies and whether it moves from the disposal site, especially into the Gulf of the Farallones National Marine Sanctuary. As part of this monitoring program, the U.S. Geological Survey (USGS) Coastal and Marine Geology Program (CMGP) deployed arrays of instruments on three moorings near the EPA disposal site from November 1997 to November 1998. This report describes the results and findings of this field monitoring experiment.

The fate of deoxynivalenol and ochratoxin A during the breadmaking process, effects of sourdough use and bran content.

PubMed

Vidal, A; Marín, S; Morales, H; Ramos, A J; Sanchis, V

2014-06-01

Deoxynivalenol (DON) and ochratoxin A (OTA) are mycotoxins produced by fungal species which can contaminate, alone or simultaneously, cereal-based products such as bread. Due to the increasing interest in the beneficial effects of dietary bran, bran bread has attained high consumption. Usually, the higher mycotoxin concentrations in cereals are found in the external layers of the grain (bran), leading to higher concentration of DON and OTA in breads with added bran. Moreover, the use of sourdough in breadmaking is increasing, but no studies about its effect in the mycotoxins content exist. The objective of this study was to determine the variation of concentration of these mycotoxins during the breadmaking process including the following factors: two initial mycotoxin concentrations in the initial mix of ingredients, four different bran contents, and use of sourdough. OTA was confirmed to be quite stable during the breadmaking process, regardless of the assayed factors. DON concentration during breadmaking was not significantly affected by bran content of bread. However, it was significantly affected by kneading and fermentation steps in opposite way depending on sourdough use and flour contamination level: if DON reduction occurs during fermentation, this leads to a safer situation, but the possible increase in DON should be considered with care, as it can compensate the expected dilution effect by recipe. Finally, the results on deoxynivalenol-3-glucoside (DON-3-G), although preliminar, suggest an increase of this toxin during fermentation, but mainly during baking. Copyright © 2014 Elsevier Ltd. All rights reserved.

[CT scan evaluation of the syndesmotic diastasis in AO/OTA B and C ankle fractures].

PubMed

Paredes-Vázquez, R; Sesma-Villalpando, R A; Herrera-Tenorio, G; Romero-Ogawa, T

2011-01-01

There are anatomical variants of the tibiofibular syndesmosis that lead to changes in the radiographic criteria applied to its injury. To determine the syndesmotic diastasis using CAT scan in B and C (AO/OTA) ankle fractures and relate the anatomical variants of the tibial incisure with the separation from the fibula. Comparative, cross-sectional and prolective screening that included all patients with B and C (AO/OTA) ankle fractures who completed their X-ray and CAT scan assessment. The radiographic parameters included the tibiofibular clearance, tibiofibular overlapping and the internal clearance. The length, depth and shape of the tibial incisure were measured with CAT scan. The statistical method used was the chi2. The total number of patients was 17:8 females (47%) and 9 males (53%), with a mean age of 41 years. Fourteen (82%) had a syndesmotic fracture and 3 had suprasyndesmotic fractures. The CAT scan found 10 concave incisures, 4 irregular and 3 flat ones. The mean depth of the incisure was 2.82 +/- 0.89 mm, and the mean width was 22.18 +/- 3.04. No syndesmotic diastasis was detected radiographically in 6 cases (35.2%); the CAT scan only detected 3 of them (17.7%). The diagnosis of syndesmotic diastasis was made with plain X-rays in 11 cases (64.8%) and with CAT scan in 14 (82.3%) (p = 0.043). The X-rays are questionable to define the syndesmotic diastasis, so the CAT scan should be considered in cases of a doubtful diagnosis.

Biocontrol of ochratoxigenic moulds (Aspergillus ochraceus and Penicillium nordicum) by Debaryomyces hansenii and Saccharomycopsis fibuligera during speck production.

PubMed

Iacumin, Lucilla; Manzano, Marisa; Andyanto, Debbie; Comi, Giuseppe

2017-04-01

Speck is a meat product obtained from the deboned leg of pork that is salted, smoked and seasoned for four to six months. During speck seasoning, Eurotium rubrum and Penicillium solitum grow on the surface and collaborate with other moulds and tissue enzymes to produce the typical aroma. Both of these strains usually predominate over other moulds. However, moulds producing ochratoxins, such as Aspergillus ochraceus and Penicillium nordicum, can also co-grow on speck and produce ochratoxin A (OTA). Consequently, speck could represent a potential health risk for consumers. Because A. ochraceus and P. nordicum could represent a problem for artisanal speck production, the aim of this study was to inhibit these mould strains using Debaryomyces hansenii and Saccharomycopsis fibuligera. Six D. hansenii and six S. fibuligera strains were tested in vitro to inhibit A. ochraceus and P. nordicum. The D. hansenii DIAL 1 and S. fibuligera DIAL 3 strains demonstrated the highest inhibitory activity and were selected for in vivo tests. The strains were co-inoculated on fresh meat cuts for speck production with both of the OTA-producing moulds prior to drying and seasoning. At the end of seasoning (six months), OTA was not detected in the speck treated with both yeast strains. Because the yeasts did not adversely affect the speck odour or flavour, the strains are proposed as starters for the inhibition of ochratoxigenic moulds. Copyright © 2016 Elsevier Ltd. All rights reserved.

NICMOS Focus and HST Breathing

NASA Astrophysics Data System (ADS)

Suchkov, A.; Hershey, J.

1998-09-01

The program 7608 monitored on a biweekly basis NICMOS camera foci from June 9, 1997, through February 18, 1998. Each of the biweekly observations included 17 measurements of focus position (focus sweeps), individually for each of the three cameras. The measurements for camera 1 and camera 3 foci covered one or two HST orbital periods. Comparison of these measurements with the predictions of the three OTA focus breathing models has shown the following. (1). Focus variations seen in NICMOS focus sweeps correlate well with the OTA focus thermal breathing as predicted by breathing models (“4- temperature”, “full-temperature”, and “attitude” models). Thus they can be attributed mostly to the HST orbital temperature variation. (2). The amount of breathing (breathing amplitude) has been found to be on average larger in the first orbit after a telescope slew to a new target. This is explained as being due to additional thermal perturbations caused by the change in the HST attitude as the telescope repoints to a new target. (3). In the first orbit, the amount of focus change predicted by the 4-temperature model is about the same as that seen in the focus sweeps data (breathing scale factor ~1). However the full-temperature model predicts a two times smaller breathing amplitude (breathing scale factor ~1.7). This suggests that the light shield temperatures are more responsive to the attitude change than temperatures from the other temperature sensors. The results of this study may help to better understand the HST thermal cycles and to improve the models describing the impact of those on both the OTA and NICMOS focus.

A paradigm shift in the surgical reconstruction of extra-articular distal humeral fractures: single-column plating.

PubMed

Meloy, Gregory M; Mormino, Matthew A; Siska, Peter A; Tarkin, Ivan S

2013-11-01

The study aimed (1) to examine if there are equivalent results in terms of union, alignment and elbow functionally comparing single- to dual-column plating of AO/OTA 13A2 and A3 distal humeral fractures and (2) if there are more implant-related complications in patients managed with bicolumnar plating compared to single-column plate fixation. This was a multi-centred retrospective comparative study. The study was conducted at two academic level 1 trauma centres. A total of 105 patients were identified to have surgical management of extra-articular distal humeral fractures Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) 13A2 and AO/OTA 13A3). Patients were treated with traditional dual-column plating or a single-column posterolateral small-fragment pre-contoured locking plate used as a neutralisation device with at least five screws in the short distal segment. The patients' elbow functionality was assessed in terms of range of motion, union and alignment. In addition, the rate of complications between the groups including radial nerve palsy, implant-related complications (painful prominence and/or ulnar nerve neuritis) and elbow stiffness were compared. Patients treated with single-column plating had similar union rates and alignment. However, single-column plating resulted in a significantly better range of motion with less complications. The current study suggests that exposure/instrumentation of only the lateral column is a reliable and preferred technique. This technique allows for comparable union rates and alignment with increased elbow functionality and decreased number of complications. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of Penicillium mycotoxins on the cytokine gene expression, reactive oxygen species production, and phagocytosis of bovine macrophage (BoMacs) function.

PubMed

Oh, Se-Young; Mead, Philip J; Sharma, Bhawani S; Quinton, V Margaret; Boermans, Herman J; Smith, Trevor K; Swamy, H V L N; Karrow, Niel A

2015-12-25

Bovine macrophages (BoMacs) were exposed to the following Penicillium mycotoxins (PM): citrinin (CIT), ochratoxin A (OTA), patulin (PAT), mycophenolic acid (MPA) and penicillic acid (PA). PM exposure at the concentration that inhibits proliferation by 25% (IC25) differentially for 24h altered the gene expression of various cytokines. OTA significantly induced IL-1α expression (p<0.05), while the expression of IL-6 was suppressed (p<0.01). MPA significantly induced the expression of IL-1α (p<0.05) and reduced the expression of IL-12α (p<0.01) and IL-10 (p<0.01). PAT significantly suppressed the expression of IL-23 (p<0.01), IL-10 (p<0.05) and TGF-β (p<0.05). Some PMs also affected reactive oxygen species (ROS) and phagocytosis of Mycobacterium avium ssp. Paratuberculosis (MAP) at higher concentrations. PAT and PA for example, significantly decreased the percent phagocytosis of MAP at 5.0 (p<0.01) and 15.6 μM (p<0.01), respectively, but only PA significantly suppressed PAM-3-stimulated ROS production at 62.5 (p<0.05) and 250.0 μM (p<0.01). OTA significantly increased the percent phagocytosis of MAP at 6.3 (p<0.05) and 12.5 μM (p<0.01). These findings suggest that exposure to sub-lethal concentrations of PMs can affect macrophage function, which could affect immunoregulation and innate disease resistance to pathogens. Copyright © 2015 Elsevier Ltd. All rights reserved.

Transportation of hazardous materials : state and local activities

DOT National Transportation Integrated Search

1986-03-01

Report is the first of two Office of Technology Assessment (OTA) reports : examining the transportation of hazardous materials in the U. S. in order to : assist the Congress in its deliberations on reauthorization of the Hazardous : Materials Transpo...

Homogeneous and label-free electrochemiluminescence aptasensor based on the difference of electrostatic interaction and exonuclease-assisted target recycling amplification.

PubMed

Ni, Jiancong; Yang, Weiqiang; Wang, Qingxiang; Luo, Fang; Guo, Longhua; Qiu, Bin; Lin, Zhenyu; Yang, Huanghao

2018-05-15

The difference of electrostatic interaction between free Ru(phen) 3 2+ and Ru(phen) 3 2+ embedded in double strand DNA (dsDNA) to the negatively charged indium tin oxide (ITO) electrode has been applied to develop a homogeneous and label-free electrochemiluminescence (ECL) aptasensor for the first time. Ochratoxin A (OTA) has been chosen as the model target. The OTA aptamer is first hybridized with its complementary single strand DNA (ssDNA) to form dsDNA and then interacted with Ru(phen) 3 2+ via the grooves binding mode to form dsDNA-Ru(phen) 3 2+ complex, which remains negatively charged feature as well as low diffusion capacity to the negatively charged ITO electrode surface owing to the electrostatic repulsion. Meanwhile, the intercalated Ru(phen) 3 2+ in the grooves of dsDNA works as an ECL signal reporter instead of the labor-intensive labeling steps and can generate much more ECL signal than that from the labeling probe. In the presence of target, the aptamer prefers to form an aptamer-target complex in lieu of dsDNA, which induces the releasing of Ru(phen) 3 2+ from the dsDNA-Ru(phen) 3 2+ complex into the solution. With the assistance of RecJ f exonuclease (a ssDNA specific exonuclease), the released ssDNA and the aptamer in the target-complex were digested into mononucleotides. In the meantime, the target can be also liberated from OTA-aptamer complex and induce target cycling and large amount of free Ru(phen) 3 2+ present in the solution. Since Ru(phen) 3 2+ contains positive charges, which can diffuses easily to the ITO electrode surface because of electrostatic attraction, causing an obviously enhanced ECL signal detected. Under the optimal conditions, the enhanced ECL of the system has a linear relationship with the OTA concentration in the range of 0.01-1.0 ng/mL with a detection limit of 2 pg/mL. This innovative system not only expands the immobilization-free sensors in the electrochemiluminescent fields, but also can be developed for the detection of different targets easily with the same strategy by changing the aptamer used. Copyright © 2018 Elsevier B.V. All rights reserved.

Evaluation of the control ability of five essential oils against Aspergillus section Nigri growth and ochratoxin A accumulation in peanut meal extract agar conditioned at different water activities levels.

PubMed

Passone, María A; Girardi, Natalia S; Etcheverry, Miriam

2012-10-15

Essential oils (EOs) from boldo [Pëumus boldus Mol.], poleo [Lippia turbinata var. integrifolia (Griseb.)], clove [Syzygium aromaticum L.], anise [Pimpinella anisum] and thyme [Thymus vulgaris]) obtained by hydrodistillation were evaluated for their effectiveness against the growth of Aspergillus niger aggregate and A. carbonarius and accumulation of ochratoxin A (OTA). The evaluation was performed by compound dissolution at the doses of 0, 500, 1500 and 2500μL/L in peanut meal extract agar (PMEA) and exposure to volatiles of boldo, poleo (0, 1000, 2000 and 3000μL/L) and clove oils (0, 1000, 3000 and 5000μL/L), taking into account the levels of the water activity of the medium (a(W) 0.98, 0.95, 0.93). Statistical analyses on growth of Aspergillus strains indicated that the major effect was produced by oil concentrations followed by substrate a(W), and that reductions in antifungal efficiency of the oils tested were observed in vapor exposure assay. At all a(W) levels, complete fungal growth inhibition was achieved with boldo EO at doses of 1500 and 2000μL/L by contact and volatile assays, respectively. Contact exposure by poleo and clove EOs showed total fungal inhibition at the middle level tested of 1500μL/L, regardless of a(W), while their antifungal effects in headspace volatile assay were closely dependent on medium a(W). The fumigant activity of poleo (2000μL/L) and clove oils (3000μL/L) inhibited growth rate by 66.0% and 80.6% at a(W) 0.98 and 0.93, respectively. OTA accumulation was closely dependent on a(W) conditions. The antiochratoxigenic property of the volatile fractions of boldo, poleo and clove EOs (1000μL/L) was more significant at low a(W) levels, inhibition percentages were estimated at 14.7, 41.7 and 78.5% at a(W) 0.98, 0.95 and 0.93, respectively. Our results suggest that boldo, poleo and clove oils affect the OTA biosynthesis pathway of both Aspergillus species. This finding leaves open the possibility of their use by vapor exposure as effective non-toxic biopreservatives against OTA contamination in stored peanuts. Copyright © 2012 Elsevier B.V. All rights reserved.

Biodiversity and ochratoxin A profile of Aspergillus section Nigri populations isolated from wine grapes in Cyprus vineyards.

PubMed

Pantelides, Iakovos S; Aristeidou, Efi; Lazari, Maria; Tsolakidou, Maria-Dimitra; Tsaltas, Dimitris; Christofidou, Maria; Kafouris, Demetris; Christou, Eftychia; Ioannou, Nicolas

2017-10-01

The objective of this study was to evaluate the biodiversity of Aspergillus section Nigri populations from Cyprus vineyards by morphological, toxigenic and phylogenetic analysis. Aspergillus section Nigri populations were isolated from grapes of the varieties 'Maratheftiko' and 'Cabernet Sauvignon' originating from six growing regions of Cyprus during 2010 and 2011 years. The isolation frequency of Aspergillus section Nigri from grape samples was 43.3% and a total of 284 isolates were selected for further analyses based on the macroscopic characteristics of black aspergilli. The isolates were characterized by sequencing analysis of the calmodulin gene in order to identify species responsible for ochratoxin A (OTA) production. The phylogenetic analysis showed that the isolates were grouped in three major clusters. The A. tubingensis cluster included 262 isolates (92.25%), the A. niger cluster included 15 isolates identified as A. niger (5.3%) and 6 isolates identified as A. welwitschiae (2.1%). One isolate was classified as A. carbonarius (0.35%) and was grouped in a cluster together with the reference isolates of A. carbonarius, A. sclerotioniger, A. sclerotiocarbonarius and A. ibericus. All the isolates were evaluated for their ochratoxigenic ability by HPLC coupled with a fluorescence detector (HPLC-FLD) and the positive isolates were re-examined using ultra high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). The Aspergillus carbonarius isolate produced an average quantity of 1436.1 ng OTA/g Czapek Yeast Agar (CYA); From the A. niger strains three isolates (20%) produced OTA and only one isolate from A. welwitschiae (16.7%) was proved ochratoxigenic with toxin production average at 23.9 ng/g and 9.1 ng/g CYA respectively. Grape must samples derived from the collected berries were also analyzed for OTA and none of the samples were found contaminated with the mycotoxin. The results showed that the geographic area and the meteorological conditions had no significant effect on the incidence and the distribution of black aspergilli in this 2-year project. However, absence of rainfall and low humidity during the harvesting period were critical for the low incidence of the ochratoxigenic A. carbonarius on grapes. Copyright © 2017 Elsevier Ltd. All rights reserved.

The NGST Yardstick Integrated Science Instrument Module (ISIM) Feasibility Study

NASA Astrophysics Data System (ADS)

Greenhouse, M. A.; NGST ISIM Team

1999-05-01

The Next Generation Space Telescope (NGST) Integrated Science Instrument Module (ISIM) is a distributed system consisting of a cryogenic instrument module that is integrated with the Optical Telescope Assembly (OTA) and science processors, software, and other electronics located in the Space Support Module (SSM). The ISIM system provides structure, environment, and data handling for several modular science instruments as well as several components of the OTA optics train. An ISIM baseline design and feasibility study is ongoing at GSFC. This pre-Phase A design was developed for integration with the Yardstick NGST architecture and packaging in a 5 m class EELV fairing. The goals of this study are to: [1] demonstrate mission science feasibility, [2] assess ISIM engineering and cost feasibility, [3] identify ISIM technology challenge areas,and [4] enable smart customer procurement of the NGST. In depth results from this work beyond those displayed here can be found at: http://www701.gsfc.nasa.gov/isim/isim.htm The flight ISIM will be developed by a GSFC led IPT that includes members from the STScI and, during Phase A/B, will grow to include the NGST Prime Contractor, and science instrument development teams from European, Canadian , and US science communities. Science instruments will be competitively procured from the science community, and will be integrated into the ISIM by GSFC. The flight qualified ISIM will then be delivered by GSFC to the NGST Prime Contractor for observatory level integration. At the start of NGST Phase A (Spring 1999), two competing prime contractors will begin development of separate NGST architectures, and the ISIM IPT will develop two ISIM designs corresponding to these architectures. Down selection to a single design will occur during mid 2001. The ISIM team welcomes science community feedback. Contact the IPT lead: Matt Greenhouse: matt@stars.gsfc.nasa.gov.

Rebuilding the foundations : a special report on state and local public works financing and management

DOT National Transportation Integrated Search

1990-03-01

In 1988, prompted by the many national studies calling for more investment in : public works infrastructure, Congress asked the Office of Technology Assessment : (OTA) to evaluate how technologies, management, and financing could improve : public wor...

Isotherm modeling of organic activated bentonite and humic acid polymer used as mycotoxin adsorbents.

PubMed

Santos, R R; Vermeulen, S; Haritova, A; Fink-Gremmels, J

2011-11-01

The aim of the current study was to evaluate and compare two representative samples of different classes of adsorbents intended for use as feed additives in the prevention or reduction of the adverse effects exerted by mycotoxins, specifically ochratoxin A (OTA) and zearalenone (ZEN). The adsorbents, an organically activated bentonite (OAB) and a humic acid polymer (HAP), were tested in a common in vitro model with a pH course comparing the maximum pH changes that can be expected in the digestive system of a monogastric animal, i.e. pH 7.4 for the oral cavity, pH 3.0 for the stomach, and pH 8.4 for the intestines. In the first experiment, the concentration-dependent adsorbent capacity of OAB and HAB were tested using a fixed concentration of either mycotoxin. Thereafter, adsorption was evaluated applying different isotherms models, such as Freundlich, Langmuir, Brunauer-Emmett-Teller (BET) and Redlich-Peterson, to characterize the adsorption process as being either homo- or heterogeneous and representing either mono- or multilayer binding. At the recommended statutory level for the mycotoxins of 0.1 mg kg(-1) OTA and 0.5 mg kg(-1) ZEN, OAB showed an adsorbed capacity of >96% towards both mycotoxins, regardless of the pH. The HAP product was also able to absorb >96% of both mycotoxins at pH 3.0, but extensive desorption occurred at pH 8.4. Based on χ-square (χ(2)) values, Langmuir and Redlich-Peterson equations proved to be the best models to predict monolayer equilibrium sorption of OTA and ZEN onto the organically activated bentonite and the humic acid polymer. The applied methodology has a sufficient robustness to facilitate further comparative studies with different mycotoxin-adsorbing agents.

The UltraLightweight Technology for Research in Astronomy (ULTRA) Project

NASA Astrophysics Data System (ADS)

Twarog, B. A.; Anthony-Twarog, B. J.; Shawl, S. J.; Hale, R.; Taghavi, R.; Fesen, R.; Etzel, P. B.; Martin, R.; Romeo, R.

2004-12-01

The collaborative focus of four academic departments (Univ. of Kansas Aerospace Engineering, Univ. of Kansas Physics & Astronomy, San Diego State University Astronomy and Dartmouth College Astronomy) and a private industry partner (Composite Mirror Applications, Inc.-CMA, Inc.) is a three-year plan to develop and test UltraLightweight Technology for Research in Astronomy (ULTRA). The ULTRA technology, using graphite fiber composites to fabricate mirrors and telescope structures, offers a versatile and cost-effective tool for optical astronomy, including the economical fabrication and operation of telescopes ranging from small (1m or smaller) aperture for education and research to extremely large (30m+) segmented telescopes (ELTs). The specific goal of this NSF-funded three-year Major Research Instrumentation project is to design, build, and test a 1m-class optical tube assembly (OTA) and mirrors constructed entirely from composites. In the first year of the project, the team has built and is field-testing two 0.4m prototypes to validate the optical surfaces and figures of the mirrors and to test and refine the structural dynamics of the OTA. Preparation for design and construction of the 1m telescope is underway. When completed in late 2005, the ULTRA telescope will be operated remotely from Mt. Laguna Observatory east of San Diego, where it will undergo a period of intensive optical and imaging tests. A 0.4m prototype OTA with mirrors (12 kg total weight) will be on display at the meeting. Support of this work by NSF through grants AST-0320784 and AST-0321247, NASA grant NCC5-600, the University of Kansas, and San Diego State University is gratefully acknowledged.

Inhibitory effect of double atmospheric pressure argon cold plasma on spores and mycotoxin production of Aspergillus niger contaminating date palm fruits.

PubMed

Ouf, Salama A; Basher, Abdulrahman H; Mohamed, Abdel-Aleam H

2015-12-01

Aspergillus niger has been reported as a potentially dangerous pathogen of date-palm fruits in Saudi Arabia due to the production of fumonisin B2 (FB2 ) and ochratoxin A (OTA). In a trial to disinfect this product, a double atmospheric pressure argon cold plasma (DAPACP) jet system was set up and evaluated against spore germination and mycotoxin production of the pathogen. The plasma jets were characterised photographically, electrically and spectroscopically. DAPACP jet length increases with the increase of argon flow rate, with optimum rate at 3.5 L min(-1) . The viability of A. niger spores, inoculated onto sterilised date palm fruit discs, progressively decreases with extension of the exposure time of DAPACP due to the more quantitative amount of OH and O radicals interacting with the examined samples. There was a progressive reduction of the amount of FB2 and OTA detected in date palm discs on extension of the exposure time of the plasma-treated inoculums at flow rate of 3.5 L min(-1) . FB2 was not detected in the discs inoculated with 6-min plasma-treated A. niger, while OTA was completely absent when the fungus was treated for 7.5 min. DAPACP showed promising results in dry fruit decontamination and in inhibition of mycotoxin release by A. niger contaminating the fruits. The progress in the commercial application of cold plasma needs further investigation concerning the ideal width of the plasma output to enable it to cover wider surfaces of the sample and consequently inducing greater plasma performance. © 2014 Society of Chemical Industry.

Survey of Alternaria Toxins and Other Mycotoxins in Dried Fruits in China

PubMed Central

Wei, Dizhe; Wang, Yao; Jiang, Dongmei; Feng, Xiaoyuan; Li, Jun; Wang, Meng

2017-01-01

Occurrence of toxigenic molds and mycotoxins on dried fruits is a worldwide problem, but limited information is available in China. A total of 220 dried fruits (raisins, dried apricots, dates and wolfberries) purchased from China were analyzed for 17 mycotoxins (i.e., Alternaria toxins, ochratoxin A (OTA), patulin (PAT) and trichothecenes) by UPLC-MS/MS, combined with a single-step cleanup. The result showed that at least one mycotoxin was detected in 142 samples (64.6%). The lowest incidence of contaminated samples was observed in dried apricots (48.2%), and the highest incidence in dried wolfberries (83.3%). The Alternaria toxins seemed to be the major problem in dried fruits, rather than OTA or PAT. Tenuazonic acid (TeA) was the predominant mycotoxin, in both frequency and concentration, ranging from 6.9 to 5665.3 μg kg−1, followed by tentoxin (TEN; 20.5%), and mycophenolic acid (MPA; 19.5%). Moreover, raisins are more likely to be contaminated with OTA than the other dried fruits. Penicillic acid (PA) was detected only in dried dates, and PAT was detected only in one apricot sample. In addition, our results also showed that the simultaneous presence of 2–4 mycotoxins was observed in 31.4% of dried fruits. TeA and TEN were the most frequent combination, detected in 29 (13.2%) samples, followed by TeA and MPA with a prevalence of 11.4%. Therefore, the results of this survey suggest the need for wider monitoring on the contamination of these mycotoxins, especially Alternaria toxins in agro-products, and indicate the importance of setting a maximum limit for Alternaria toxins in China. PMID:28672847

Surveys of rice sold in Canada for aflatoxins, ochratoxin A and fumonisins

PubMed Central

Bansal, J.; Pantazopoulos, P.; Tam, J.; Cavlovic, P.; Kwong, K.; Turcotte, A.-M.; Lau, B.P.-Y.; Scott, P.M.

2011-01-01

Approximately 200 samples of rice (including white, brown, red, black, basmati and jasmine, as well as wild rice) from several different countries, including the United States, Canada, Pakistan, India and Thailand, were analysed for aflatoxins, ochratoxin A (OTA) and fumonisins by separate liquid Chromatographic methods in two different years. The mean concentrations for aflatoxin B1 (AFB1) were 0.19 and 0.17 ng g−1 with respective positive incidences of 56% and 43% (≥ the limit of detection (LOD) of 0.002 ng g−1). Twenty-three samples analysed in the second year also contained aflatoxin B2 (AFB2) at levels ≥LOD of 0.002 ng g−1 The five most contaminated samples in each year contained 1.44–7.14 ng AFB1 g−1 (year 1) and 1.45–3.48 ng AFB1 g−1 (year 2); they were mostly basmati rice from India and Pakistan and black and red rice from Thailand. The average concentrations of ochratoxin A (OTA) were 0.05 and 0.005 ng g−1 in year 1 and year 2, respectively; incidences of samples containing ≥LOD of 0.05 ng g−1 were 43% and 1%, respectively, in the 2 years. All positive OTA results were confirmed by LC-MS/MS. For fumonisins, concentrations of fumonisin B1 (FB1) averaged 4.5 ng g−1 in 15 positive samples (≥0.7 ng g−1) from year 1 (n = 99); fumonisin B2 (FB2) and fumonisin B3 (FB3) were also present (≥1 ng g−1). In the second year there was only one positive sample (14 ng g−1 FB1) out of 100 analysed. All positive FB1 results were confirmed by LC-MS/MS. PMID:21623501

Using Optimal Test Assembly Methods for Shortening Patient-Reported Outcome Measures: Development and Validation of the Cochin Hand Function Scale-6: A Scleroderma Patient-Centered Intervention Network Cohort Study.

PubMed

Levis, Alexander W; Harel, Daphna; Kwakkenbos, Linda; Carrier, Marie-Eve; Mouthon, Luc; Poiraudeau, Serge; Bartlett, Susan J; Khanna, Dinesh; Malcarne, Vanessa L; Sauve, Maureen; van den Ende, Cornelia H M; Poole, Janet L; Schouffoer, Anne A; Welling, Joep; Thombs, Brett D

2016-11-01

To develop and validate a short form of the Cochin Hand Function Scale (CHFS), which measures hand disability, for use in systemic sclerosis, using objective criteria and reproducible techniques. Responses on the 18-item CHFS were obtained from English-speaking patients enrolled in the Scleroderma Patient-Centered Intervention Network Cohort. CHFS unidimensionality was verified using confirmatory factor analysis, and an item response theory model was fit to CHFS items. Optimal test assembly (OTA) methods identified a maximally precise short form for each possible form length between 1 and 17 items. The final short form selected was the form with the least number of items that maintained statistically equivalent convergent validity, compared to the full-length CHFS, with the Health Assessment Questionnaire (HAQ) disability index (DI) and the physical function domain of the 29-item Patient-Reported Outcomes Measurement Information System (PROMIS-29). There were 601 patients included. A 6-item short form of the CHFS (CHFS-6) was selected. The CHFS-6 had a Cronbach's alpha of 0.93. Correlations of the CHFS-6 summed score with HAQ DI (r = 0.79) and PROMIS-29 physical function (r = -0.54) were statistically equivalent to the CHFS (r = 0.81 and r = -0.56). The correlation with the full CHFS was high (r = 0.98). The OTA procedure generated a valid short form of the CHFS with minimal loss of information compared to the full-length form. The OTA method used was based on objective, prespecified criteria, but should be further studied for viability as a general procedure for shortening patient-reported outcome measures in health research. © 2016, American College of Rheumatology.

Oversight hearings on P. L. 93-577, ERDA Plan and Program. Hearings before the Subcommittee on Energy Research, Development and Demonstration of the Committee on Science and Technology, U. S. House of Representatives, Ninety-Fourth Congress, Second Session

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1976-01-01

The purpose of the hearings was to examine the comprehensive plan and program for dealing with energy that ERDA submitted to Congress on June 30, 1975. Included as an appendix to these hearings is the October 1975 report of the Office of Technology Assessment (OTA) entitled, ''An Analysis of the ERDA Plan and Program'' (for abstract of this report, see EAPA 2:79). Testifying on Jan. 22 was the director of OTA, Emilio Q. Daddario, and chairmen of various task groups that assisted in the ERDA analysis, namely: Dr. John Gibbons, Conservation; Dr. Paul Craig, Overview Panel; Dr. Alvin Weinberg, Nuclear;more » Dr. Stanford S. Penner, Environmental and Health; and Dr. Jerry Grey, Solar; also present, and participating in the question and answer portion was Lionel Johns, head of the energy projects and programs in OTA. Testifying at the Jan. 23 hearings were experts presenting environmental, scientific, and engineering viewpoints, namely: Dr. Donald McDonald, director of the environmental studies program at Dartmouth College; Dr. Reginald Vachon, Auburn University, representing the American Society of Mechanical Engineers; and Dr. Thomas Lee, General Electric Co., representing the Inst. of Electrical and Electronics Engineers. The final hearings on Jan. 29 included the testimony of Dr. Robert W. Fri, Deputy Administrator, ERDA, and that of each of five assistant administrators: Dr. John Teem, Solar, Geothermal, and Advanced Energy Systems; Dr. Austin Heller, Conservation; Dr. Richard W. Roberts, Nuclear Energy; Dr. Roger W. A. LeGassie, Planning and Analysis; and Dr. James Liverman, Environment and Safety. (LMT)« less

Is there a role for intramedullary nails in the treatment of simple pilon fractures? Rationale and preliminary results.

PubMed

Marcus, Matthew S; Yoon, Richard S; Langford, Joshua; Kubiak, Erik N; Morris, Andrew J; Koval, Kenneth J; Haidukewych, George J; Liporace, Frank A

2013-08-01

Certain patients with pilon fractures present with significant soft-tissue swelling or with a poor soft-tissue envelope typically not amenable to definitive fixation in the early time period. The objective of this study was to review the treatment of simple intra-articular fractures of the tibial plafond (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) type 43C1-C2) via intramedullary nailing (IMN) with the assessment of clinical and radiographic results and any associated complications. Retrospective clinical and radiological reviews of 31 patients sustaining AO/OTA type 43C distal tibial fractures treated with IMN were evaluated. Our main outcome measurement included achievable alignment in the immediate postoperative period and at the time of union along with complications or need for secondary procedures within the first year of follow-up. Seven patients were lost to follow-up. All the remaining patients achieved bony union at a mean union time of 14.1 ± 4.9 weeks with no evidence of malunion or malrotation. All patients were at full-weight-bearing status at 1-year follow-up. Complications were notable for one delayed union, one non-union, one patient with superficial wound drainage, two with deep infection, one with symptomatic hardware and one with deep vein thrombosis. Simple articular fractures of the tibial plafond (AO/OTA type 43C) treated via IMN can achieve excellent alignment and union rates with proper patient selection and surgical indication. One should not hesitate to use additional bone screws or plating options to help achieve better anatomic reduction. However, larger, prospective randomised trials comparing plating versus nailing, in experienced hands, are needed to completely delineate the utility of this treatment modality. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of loop-mediated isothermal amplification (LAMP) assay for the rapid detection of Penicillium nordicum in dry-cured meat products.

PubMed

Ferrara, M; Perrone, G; Gallo, A; Epifani, F; Visconti, A; Susca, A

2015-06-02

The need of powerful diagnostic tools for rapid, simple, and cost-effective detection of food-borne fungi has become very important in the area of food safety. Currently, several isothermal nucleic acid amplification methods have been developed as an alternative to PCR-based analyses. Loop-mediated isothermal amplification (LAMP) is one of these innovative methods; it requires neither gel electrophoresis to separate and visualize the products nor expensive laboratory equipment and it has been applied already for detection of pathogenic organisms. In the current study, we developed a LAMP assay for the specific detection of Penicillium nordicum, the major causative agent of ochratoxin A contamination in protein-rich food, especially dry-cured meat products. The assay was based on targeting otapksPN gene, a key gene in the biosynthesis of ochratoxin A (OTA) in P. nordicum. Amplification of DNA during the reaction was detected directly in-tube by color transition of hydroxynaphthol blue from violet to sky blue, visible to the naked eye, avoiding further post amplification analyses. Only DNAs isolated from several P. nordicum strains led to positive results and no amplification was observed from non-target OTA and non OTA-producing strains. The assay was able to detect down to 100 fg of purified targeted genomic DNA or 10(2) conidia/reaction within 60 min. The LAMP assay for detection and identification of P. nordicum was combined with a rapid DNA extraction method set up on serially diluted conidia, providing an alternative rapid, specific and sensitive DNA-based method suitable for application directly "on-site", notably in key steps of dry-cured meat production. Copyright © 2015 Elsevier B.V. All rights reserved.

Design, simulation and comparative analysis of CNT based cascode operational transconductance amplifiers

NASA Astrophysics Data System (ADS)

Nizamuddin, M.; Loan, Sajad A.; Alamoud, Abdul R.; Abbassi, Shuja A.

2015-10-01

In this work, design and calibrated simulation of carbon nanotube field effect transistor (CNTFET)-based cascode operational transconductance amplifiers (COTA) have been performed. Three structures of CNTFET-based COTAs have been designed using HSPICE and have been compared with the conventional CMOS-based COTAs. The proposed COTAs include one using pure CNTFETs and two others that employ CNTFETs, as well as the conventional MOSFETs. The simulation study has revealed that the CNTFET-based COTAs have significantly outperformed the conventional MOSFET-based COTAs. A significant increase in dc gain, output resistance and slew rate of 81.4%, 25% and 13.2%, respectively, have been achieved in the proposed pure CNT-based COTA in comparison to the conventional CMOS-based COTA. The power consumption in the pure CNT-COTA is 324 times less in comparison to the conventional CMOS-COTA. Further, the phase margin (PM), gain margin (GM), common mode and power supply rejection ratios have been significantly increased in the proposed CNT-based COTAs in comparison to the conventional CMOS-based COTAs. Furthermore, to see the advantage of cascoding, the proposed CNT-based cascode OTAs have been compared with the CNT-based OTAs. It has been observed that by incorporating the concept of cascode in the CNTFET-based OTAs, significant increases in gain (12.5%) and output resistance (13.07%) have been achieved. The performance of the proposed COTAs has been further observed by changing the number of CNTs (N), CNT pitch (S) and CNT diameter (DCNT) in the CNTFETs used. It has been observed that the performance of the proposed COTAs can be significantly improved by using optimum values of N, S and DCNT.

Alternative approaches to cargo policy : a supplement to an assessment of maritime trade and technology

DOT National Transportation Integrated Search

1985-08-01

When the Office of Technology Assessment (OTA) published An Assessment of Maritime Trade and Technology in October 1983, one of its principal findings was that because national interests were not defined and strategies for international negotiation h...

Robotics/Automated Systems Technicians.

ERIC Educational Resources Information Center

Doty, Charles R.

Major resources exist that can be used to develop or upgrade programs in community colleges and technical institutes that educate robotics/automated systems technicians. The first category of resources is Economic, Social, and Education Issues. The Office of Technology Assessment (OTA) report, "Automation and the Workplace," presents analyses of…

Comparative Toxicokinetics and Plasma Protein Binding of Ochratoxin A in Four Avian Species.

PubMed

Devreese, Mathias; Croubels, Siska; De Baere, Siegrid; Gehring, Ronette; Antonissen, Gunther

2018-03-07

Ochratoxin A (OTA, 0.25 mg/kg body weight) was absorbed rapidly ( T max = 0.31-1.88 h) in all avian species (broiler chickens, laying hens, turkeys, and Muscovy ducks) but more slowly in broiler chickens ( T max = 1.43-4.63 h). The absolute oral bioavailability was complete in these bird species (88.0-109.6%). Ducks have a significantly higher volume of distribution ( V d ) and turkeys a lower V d compared to chickens and layers (broiler chickens, 0.27 ± 0.12 L/kg; layers, 0.23 ± 0.08 L/kg; turkeys, 0.18 ± 0.04 L/kg; ducks, 0.76 ± 0.44 L/kg). This difference in V d can be attributed to the species-dependent differences in plasma protein binding of OTA, namely ranging between 82.2 and 88.9% in ducks and between 96.5 and 98.8% in turkeys. No significant gender differences were found in toxicokinetics or plasma protein binding.

Waste grape skins: evaluation of safety aspects for the production of functional powders and extracts for the food sector.

PubMed

Moncalvo, Alessandro; Marinoni, Laura; Dordoni, Roberta; Duserm Garrido, Guillermo; Lavelli, Vera; Spigno, Giorgia

2016-07-01

Skin powders and aqueous alcohol extracts were obtained from waste marcs from different grape varieties (Barbera, Nebbiolo, Pinot Noir, Chardonnay, Moscato and Müller-Thurgau). Both skins and extracts were analysed for the content of chemical contaminants: ochratoxin A (OTA), biogenic amines (BIAs), pesticides and metals. OTA was detected in low concentrations in Barbera, Moscato and Nebbiolo skins, but only in Barbera and Moscato extracts. Cadaverine, putrescine, ethanolamine and ethylamine were found in extracts at very low levels, while potential allergenic amines, tyramine and histamine, were never detected. Different pesticides were present in both skins and extracts. Pb and Cd were found in trace only in the powders, and K, Ca and Mg were the most abundant elements in both skin powders and extracts. Concentrations of the different contaminants were related to fibre content or total phenolics content of powders and extracts, respectively, in order to evaluate their use in the food sector.

Aflatoxins and ochratoxin a reduction in black and white pepper by gamma radiation

NASA Astrophysics Data System (ADS)

Jalili, M.; Jinap, S.; Noranizan, M. A.

2012-11-01

Irradiation is an important means of decontamination of food commodities, especially spices. The aim of the current study was to investigate the efficacy of gamma radiation (60Co) for decontaminating ochratoxin A (OTA) and aflatoxins B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) residues in artificially contaminated black and white pepper samples. The moisture content of the pepper samples was set at 12% or 18%, and the applied gamma dose ranged from 5 to 30 kGy. Mycotoxin levels were determined by high-performance liquid chromatography (HPLC) after immunoaffinity column (IAC) chromatography. Both the gamma irradiation dose and moisture content showed significant effects (P<0.05) on mycotoxin reduction. The maximum toxin reductions, found at 18% moisture content and 30 kGy, were 55.2%, 50.6%, 39.2%, 47.7% and 42.9% for OTA, AFB1, AFB2, AFG1 and AFG2, respectively.

Nanostructured zinc oxide platform for mycotoxin detection.

PubMed

Ansari, Anees A; Kaushik, Ajeet; Solanki, Pratima R; Malhotra, B D

2010-02-01

Nanostructured zinc oxide (Nano-ZnO) film has been deposited onto indium-tin-oxide (ITO) glass plate for co-immobilization of rabbit-immunoglubin antibodies (r-IgGs) and bovine serum albumin (BSA) for ochratoxin-A (OTA) detection. The results of X-ray diffraction (XRD) studies reveal the formation of Nano-ZnO with average particle size as ~5.0nm. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) techniques have been used to characterize Nano-ZnO/ITO electrode and BSA/r-IgGs/Nano-ZnO/ITO immunoelectrode. Electrochemical impedimetric response of BSA/r-IgGs/Nano-ZnO/ITO immunoelectrode obtained as a function of OTA concentration exhibits linearity as 0.006-0.01nM/dm(3), detection limit of 0.006nM/dm(3), response time as 25s and sensitivity of 189Omega/nM/dm(3)cm(-2) with a regression coefficient of 0.997. 2009 Elsevier B.V. All rights reserved.

The effect of chemical treatment on reduction of aflatoxins and ochratoxin A in black and white pepper during washing.

PubMed

Jalili, M; Jinap, S; Son, R

2011-04-01

The effect of 18 different chemicals, which included acidic compounds (sulfuric acid, chloridric acid, phosphoric acid, benzoic acid, citric acid, acetic acid), alkaline compounds (ammonia, sodium bicarbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide), salts (acetate ammonium, sodium bisulfite, sodium hydrosulfite, sodium chloride, sodium sulfate) and oxidising agents (hydrogen peroxide, sodium hypochlorite), on the reduction of aflatoxins B(1), B(2), G(1) and G(2) and ochratoxin A (OTA) was investigated in black and white pepper. OTA and aflatoxins were determined using HPLC after immunoaffinity column clean-up. Almost all of the applied chemicals showed a significant degree of reduction on mycotoxins (p < 0.05). The lowest and highest reduction of aflatoxin B(1), which is the most dangerous aflatoxin, was 20.5% ± 2.7% using benzoic acid and 54.5% ± 2.7% using sodium hydroxide. There was no significant difference between black and white peppers (p < 0.05).

Professional Reward in the Academic Fieldwork Coordinator Role.

PubMed

Stutz-Tanenbaum, Patricia; Greene, David; Hanson, Debra J; Koski, Jeanette

The purpose of this national survey was to explore perceptions of professional reward among occupational therapist (OT) and occupational therapy assistant (OTA) academic fieldwork coordinators (AFWCs). Agreement was found in ranking the value of six role factors: (1) fieldwork data management, (2) fieldwork site management, (3) fieldwork teaching and consultation, (4) departmental and institutional compliance, (5) scholarship and accreditation, and (6) laying groundwork for students in fieldwork. Both levels of AFWC indicated teaching and consultation had the highest value and data management the least. OT AFWCs placed significantly higher value on publishing articles and lower value on educating fieldwork educators about role delineation than OTA AFWCs. Five themes emerged regarding professional reward: (1) intrinsic reward, (2) collaboration, (3) development of the profession, (4) feeling appreciated, and (5) student success. AFWCs value activities involving personal interaction, promoting professional development, and facilitating student success. Results have implications for AFWC collaboration, workload distribution, and scholarship. Copyright © 2017 by the American Occupational Therapy Association, Inc.

Commercial newsgathering from space

NASA Astrophysics Data System (ADS)

1987-05-01

This memorandum does not examine the feasibility of a specific satellite system or business plan, but rather, assesses whether current government policy is appropriate to accommodate both current activities and future developments of the use of satellite images to cover newsworthy events. The mediasat term refers to a concept of a satellite system and business organization that would routinely collect news and information for media use from space. Because the mediasat concept is, for the most part, undefined, the Office of Technology Assessment (OTA) was forced to make a series of assumptions regarding fundamental issues as cost, markets, technical capability, and utility of a mediasat. Although these assumptions are critical to OTA's conclusions, they are only best guesses, based on the advice of experts in the media and in the field of remote sensing. With regard to specific issues, such as the economic viability of a mediasat or its effect on national security and foreign policy, altering these underlying assumptions could dramatically alter the conclusions reached.

Ultrafast Hole Trapping and Relaxation Dynamics in p-Type CuS Nanodisks

DOE PAGES

Ludwig, John; An, Li; Pattengale, Brian; ...

2015-06-22

CuS nanocrystals are potential materials for developing low-cost solar energy conversion devices. Understanding the underlying dynamics of photoinduced carriers in CuS nanocrystals is essential to improve their performance in these devices. In this work, we investigated the photoinduced hole dynamics in CuS nanodisks (NDs) using the combination of transient optical (OTA) and X-ray (XTA) absorption spectroscopy. OTA results show that the broad transient absorption in the visible region is attributed to the photoinduced hot and trapped holes. The hole trapping process occurs on a subpicosecond time scale, followed by carrier recombination (~100 ps). The nature of the hole trapping sites,more » revealed by XTA, is characteristic of S or organic ligands on the surface of CuS NDs. Lastly, these results not only suggest the possibility to control the hole dynamics by tuning the surface chemistry of CuS but also represent the first time observation of hole dynamics in semiconductor nanocrystals using XTA.« less

Environmental cancer risks

NASA Astrophysics Data System (ADS)

Bell, Peter M.

In a long-awaited report (‘Assessment of Technologies for Determining Cancer Risks From the Environment’), the U.S. Office of Technology Assessment (OTA) has evaluated the role of environmental factors in cancer diseases. Environment is interpreted broadly as encompassing anything that interacts with humans, including the natural environment, food, radiation, the workplace, etc. Geologic factors range from geographic location to radiation and specific minerals. The report, however, is based on an inadequate data base in most instances, and its major recommendations are related to the establishment of a national cancer registry to record cancer statistics, as is done for many other diseases. Presently, hard statistics are lacking in the establishment of some association between the cause-effect relationship of most environmental factors and most carcinogens. Of particular interest, but unfortunately based on unreliable data, are the effects of mineral substances such as ‘asbestos.’ USGS mineralogist Malcolm Ross will review asbestos and its effects on human health in the forthcoming Mineralogical Society of America's Short Course on the Amphiboles (Reviews in Mineralogy, 9, in press, 1981).

[Work organization and mobbing: application of cognitive methodology in medical circle].

PubMed

Martire, M R; Lo Cascio, G; Picciotto, D; Lo Cascio, N

2006-01-01

Mobbing is a phenomenon produced for the most part by factors related to work organization. During the medical control of workers in Universitary Policlinico Hospital of Palermo, we used a methodology (in advance applied with effectiveness by ISPESL in other institutions) that is able to evidence factors of work organization causing Mobbing. 338 out 2060 workers (total staff) with different professional figures were recruited. We evidenced the working classes that had more troubles about communications of business information, about interpersonal relationships at work with top manager, with other members of team and with colleagues. Particularly doctors and OTA, in worrying percentage, stated that they suffered psychological molestations. Aim of our study was to assay a procedure that, even if it doesn't identify proclaimed mobbing phenomenon, enables us to acquire information about relationships between business management and workers and organizational aspects perceiving by subordinates. A I level study about a phenomenon in expansion is very useful to recognize preventively intentionally made mobbing actions.

Project WP#474: Integrated Internal Inspection and Cleaning Tool Technology for Pipelines

DOT National Transportation Integrated Search

2012-08-30

PHMSA provide notification to Electricore that Other Transaction Agreement (OTA) DTPH56-10-T- 000011 was terminated in July 2011. Prior to the decision to terminate the project, a number of tasks and activities were completed by the Project Team as d...

The Evolution of Distance Learning: Technology-Mediated Interactive Learning.

ERIC Educational Resources Information Center

Dede, Christopher J.

1990-01-01

Summarizes a paper prepared for the Office of Technology Assessment (OTA) on the evolution of distance learning which begins by describing technological, the demographic, economic, political, and pedagogical forces involved. A new field is proposed called technology-mediated interactive learning (TMIL), which synthesizes distance learning,…

Information Exchange: The Impact of Scholarly Communication.

ERIC Educational Resources Information Center

Garcia, D. Linda

1990-01-01

Discusses issues relating to intellectual property rights that are being affected by information technologies. A 1986 study by the Office of Technology Assessment (OTA) is discussed; intellectual property law is described, including copyright, patents, and trade secrets; and the involvement of the university community in considering intellectual…

An Exploration of African American Students' Attitudes toward Online Learning

ERIC Educational Resources Information Center

Okwumabua, Theresa M.; Walker, Kristin M.; Hu, Xiangen; Watson, Andrea

2011-01-01

The current work presents exploratory research findings concerning African American students' attitudes toward online learning. The Online Tutoring Attitudes Scale (OTAS; Graff, 2003) was administered to 124 African American students in a positive youth development program. Findings suggest that African American students' attitudes toward…

Project SQUID. A Program of Fundamental Research on Liquid Rocket and Pulse Jet Propulsion

DTIC Science & Technology

1947-04-01

Young of Aerojet Engineering Corporation. Con- siderable time was spent with Mr. Pelton , of Aerojet Engineering Corporation, discussing the...UNAMOUNCtO iBranEjp (Ota«») , "Brooklyn Polytechnic Jnst. AUTHOB(S) DIVISION, poirer Plants, Jet and Turbine (5) SECTION. Testing (17) I

Failure Is Not an Option: A Root Cause Analysis of Failed Acquisition Programs

DTIC Science & Technology

2017-12-01

Kendall (2012, 2015). ..................................................................................4 Table 3. Description and Decision Authority...Assessment and Program Evaluation DAE Defense Acquisition Executive DAMIR Defense Acquisition Management Information Retrieval DARPA Defense Advanced...and evaluation OTA other transactions authority PARCA performance assessments and root cause analyses PBD program budget decisions PDR preliminary

Technology assessment of changes in the future use and characteristics of the automobile transportation system. Volume 3 : public participation

DOT National Transportation Integrated Search

1979-10-01

An assessment of the future use and characteristics of the automobile transportation : system was undertaken (1976-78) by OTA at the request of Senator Warren G. : Magnuson, then Chairman of the Senate Committee on Commerce, Science, and : Transporta...

Introduction: Optical trapping and applications feature issue

PubMed Central

López-Mariscal, Carlos; McGloin, David

2013-01-01

The editors introduce the Biomedical Optics Express feature issue on “Optical Trapping and Applications.” The works presented in the papers within this issue include were the focus of the third OTA Topical Meeting that was held on April 14–18, 2013, in Waikoloa, Hawaii. PMID:24298428

R&D in the maritime industry : a supplement to an assessment of maritime trade and technology

DOT National Transportation Integrated Search

1985-05-01

Since the publication of "An Assessment of Maritime Trade and Technology" by Office of Technology Assessment (OTA) in October 1983, various proposals have been made to provide incentives for research and development (R&D) in an effort to enhance the ...

Late Onset Presentation of Hori’s Nevus in and Elderly Caucasian Female

DTIC Science & Technology

2017-10-26

Acquired Bilateral Nevus of Ota-like Macules (Hori’s Nevus) are characterized clinically by bilateral blue-gray to gray-brown macules or patches most...melanocytoses, this condition is more common in Asians and is usually congenital or appears during childhood or adolescence.

Understanding our Genetic Inheritance: The U.S. Human Genome Project, The First Five Years FY 1991--1995

DOE R&D Accomplishments Database

1990-04-01

The Human Genome Initiative is a worldwide research effort with the goal of analyzing the structure of human DNA and determining the location of the estimated 100,000 human genes. In parallel with this effort, the DNA of a set of model organisms will be studied to provide the comparative information necessary for understanding the functioning of the human genome. The information generated by the human genome project is expected to be the source book for biomedical science in the 21st century and will by of immense benefit to the field of medicine. It will help us to understand and eventually treat many of the more than 4000 genetic diseases that affect mankind, as well as the many multifactorial diseases in which genetic predisposition plays an important role. A centrally coordinated project focused on specific objectives is believed to be the most efficient and least expensive way of obtaining this information. The basic data produced will be collected in electronic databases that will make the information readily accessible on convenient form to all who need it. This report describes the plans for the U.S. human genome project and updates those originally prepared by the Office of Technology Assessment (OTA) and the National Research Council (NRC) in 1988. In the intervening two years, improvements in technology for almost every aspect of genomics research have taken place. As a result, more specific goals can now be set for the project.

New Electric Power Technologies: Problems and Prospects for the 1990s.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. Office of Technology Assessment.

This report responds to a request from the House Committee on Science and Technology and its Subcommittee on Energy Development and Applications to analyze a range of new electric power generating, storage, and load management technologies. The Office of Technology Assessment (OTA) examined these technologies in terms of their current and expected…

Mechanistic Probes of Zeolitic Imidazolate Framework for Photocatalytic Application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pattengale, Brian; Yang, Sizhuo; Lee, Sungsik

2017-11-07

In this work, we report a zeolitic imidazolate framework (ZIF-67) with remarkable activity for hydrogen evolution reaction (HER) of 40,500 μmol H2/g MOF, which is, to the best of our knowledge, the highest activity achieved by any MOF system. This result necessitated assessment of its atomic-scale mechanistic function for HER using advanced spectroscopy techniques including time-resolved optical (OTA) and in situ X-ray absorption (XAS) spectroscopy. Through the correlation of OTA results with catalytic performance, we demonstrated that the electron transfer (ET) rather than energy transfer (ENT) pathway between photosensitizer and ZIF-67 is the key factor that controls the efficiency ofmore » HER activity, as HER activity that undergoes ET pathway is 3 orders of magnitude higher than that of ENT process. Using in situ XAS, we unraveled the spectral features for key intermediate species which are likely responsible for the rate determining process under turn over conditions. This work represents an original approach to study porous ZIF materials at the molecular level using advanced spectroscopic techniques, providing unprecedented insights into the photoactive nature of ZIF frameworks.« less

Correlation between obesity and severity of distal radius fractures.

PubMed

Acosta-Olivo, C; Gonzalez-Saldivar, J C; Villarreal-Villarreal, G; Torres-Botello, A; Gomez-Garcia, E; Tamez-Mata, Y; Peña-Martinez, V

2017-04-01

The incidence of obesity has increased significantly worldwide. Our hypothesis was that patients with obesity have a more severe distal radius fracture and we realized a study to evaluate this correlation between obesity and severity of distal radius fractures caused by low-energy injuries. A total of 114 patients with distal radius fracture were examined in a cross-sectional, observational study. Fractures were classified according to the international AO-Müller/Orthopedic Trauma Association (AO/OTA) classification in order to determine the severity. The patient's Body Mass Index (BMI) was calculated and a Pearson correlation was performed. The patients were predominantly female, and left side was more frequently affected. Most of the fractures were AO/OTA type A (71 patients). The majority of the involved patients in our study were overweighed or obese. We do not observe a direct correlation between grade of obesity and distal radius fracture severity. Based on the results of this study obesity and severity of distal radius fractures do not correlate. Prognostic. Level IV. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Continuous-time ΣΔ ADC with implicit variable gain amplifier for CMOS image sensor.

PubMed

Tang, Fang; Bermak, Amine; Abbes, Amira; Benammar, Mohieddine Amor

2014-01-01

This paper presents a column-parallel continuous-time sigma delta (CTSD) ADC for mega-pixel resolution CMOS image sensor (CIS). The sigma delta modulator is implemented with a 2nd order resistor/capacitor-based loop filter. The first integrator uses a conventional operational transconductance amplifier (OTA), for the concern of a high power noise rejection. The second integrator is realized with a single-ended inverter-based amplifier, instead of a standard OTA. As a result, the power consumption is reduced, without sacrificing the noise performance. Moreover, the variable gain amplifier in the traditional column-parallel read-out circuit is merged into the front-end of the CTSD modulator. By programming the input resistance, the amplitude range of the input current can be tuned with 8 scales, which is equivalent to a traditional 2-bit preamplification function without consuming extra power and chip area. The test chip prototype is fabricated using 0.18 μm CMOS process and the measurement result shows an ADC power consumption lower than 63.5 μW under 1.4 V power supply and 50 MHz clock frequency.

Implementation of electrochemical elements for an alternative detection of ochratoxin A

NASA Astrophysics Data System (ADS)

Aristizabal, D. H.; Giraldo, D. A.; Sanchez, S.; Taborda, G.; Baeza, A.

2017-01-01

Ochratoxin A (OTA) is a nephrotoxic metabolite, hepatotoxic and carcinogenic produced mainly by Aspergillus and Penicillium fungi. Usually, the mycotoxin analysed through the technique of high performance liquid chromatography. This method is expensive and takes a lot of time. Therefore, expected to automate a device of low cost, minimal instrumentation micropolarographic (MIMP) for the analysis. For this purpose, the right programming environment and the manufacturing of the software for the graphical user interface selected automation of the MIMP through the design and simulation of the circuit, imprint and assembled in a container with connection ports. Lastly, validation and analysis of Ochratoxin A by cyclic voltammetry from analogous MIMP, automatic MIMP and a potentiostat, in order to corroborate the registered data. This way, voltammetry analysis of coumarin is obtained and the simulation of the MIMP electric circuit. Therefore, this are the key data during the investigation, because the molecule of OTA can be monitored through an acid hydrolysis of amides, composed by a phenylalanine and coumaric acid group, generating the significant decrease in the costs and time of analysis.

Mycotoxin contamination in laboratory rat feeds and their implications in animal research.

PubMed

Escrivá, Laura; Font, Guillermina; Berrada, Houda; Manyes, Lara

2016-09-01

Compound feed is particularly vulnerable to multi-mycotoxin contamination. A method for the determination of 12 mycotoxins; enniatins A, A1, B, B1; aflatoxins B1, B2, G1, G2; OTA; ZEA; T-2 and HT-2 by liquid chromatography-tandem mass spectrometry has been developed and applied for the analysis of laboratory rat commercial feeds. The method trueness was checked by recovery assays at three different spiked levels (n = 9). Recoveries ranged from 73% to 112%, and the intra-day and inter-day precision were lower than 9% and 13%, respectively. Limits of quantitation were lower than 15 μg/kg. Twenty-seven laboratory rats feed samples showed multi-contamination by at least three up to six different mycotoxins. ENNs B and B1, followed by ZEA were the most prevalent mycotoxins. T-2, HT-2, and OTA were not detected. ZEA showed the highest concentration levels reaching 492 μg/kg. The results underline the importance of implementing mycotoxin regular surveillance programs for laboratory animal feeds.

Thermal stability and kinetics of degradation of deoxynivalenol, deoxynivalenol conjugates and ochratoxin A during baking of wheat bakery products.

PubMed

Vidal, Arnau; Sanchis, Vicente; Ramos, Antonio J; Marín, Sonia

2015-07-01

The stability of deoxynivalenol (DON), deoxynivalenol-3-glucoside (DON-3-glucoside), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), de-epoxy-deoxynivalenol (DOM-1) and ochratoxin A (OTA) during thermal processing has been studied. Baking temperature, time and initial mycotoxin concentration in the raw materials were assayed as factors. An improved UPLC-MS/MS method to detect DON, DON-3-glucoside, 3-ADON, 15-ADON and DOM-1 in wheat baked products was developed in the present assay. The results highlighted the importance of temperature and time in mycotoxin stability in heat treatments. OTA is more stable than DON in a baking treatment. Interestingly, the DON-3-glucoside concentrations increased (>300%) under mild baking conditions. On the other hand, it was rapidly reduced under harsh conditions. The 3-ADON decreased during the heat treatment; while DOM-1 increased after the heating process. Finally, the data followed first order kinetics for analysed mycotoxins and thermal constant rates (k) were calculated. This parameter can be a useful tool for prediction of mycotoxin levels. Copyright © 2015 Elsevier Ltd. All rights reserved.

Linear-phase delay filters for ultra-low-power signal processing in neural recording implants.

PubMed

Gosselin, Benoit; Sawan, Mohamad; Kerherve, Eric

2010-06-01

We present the design and implementation of linear-phase delay filters for ultra-low-power signal processing in neural recording implants. We use these filters as low-distortion delay elements along with an automatic biopotential detector to perform integral waveform extraction and efficient power management. The presented delay elements are realized employing continuous-time OTA-C filters featuring 9th-order equiripple transfer functions with constant group delay. Such analog delay enables processing neural waveforms with reduced overhead compared to a digital delay since it does not requires sampling and digitization. It uses an allpass transfer function for achieving wider constant-delay bandwidth than all-pole does. Two filters realizations are compared for implementing the delay element: the Cascaded structure and the Inverse follow-the-leader feedback filter. Their respective strengths and drawbacks are assessed by modeling parasitics and non-idealities of OTAs, and by transistor-level simulations. A budget of 200 nA is used in both filters. Experimental measurements with the chosen filter topology are presented and discussed.

A simple, rapid and novel method based on salting-out assisted liquid-liquid extraction for ochratoxin A determination in beer samples prior to ultra-high performance liquid chromatography coupled to tandem mass spectrometry.

PubMed

Mariño-Repizo, Leonardo; Goicoechea, Hector; Raba, Julio; Cerutti, Soledad

2018-06-07

A novel, simple, easy and cheap sample treatment strategy based on salting-out assisted liquid-liquid extraction (SALLE) for ochratoxin A (OTA) ultra-trace analysis in beer samples using ultra-high performance liquid chromatography-tandem mass spectrometry determination was developed. The factors involved in the efficiency of pretreatment were studied employing factorial design in the screening phase and the optimal conditions of the significant variables on the analytical response were evaluated using a central composite face-centred design (CCF). Consequently, the amount of salt ((NH 4 ) 2 SO 4 ), together with the volumes of sample, hydrophilic (acetone) and nonpolar (toluene) solvents, and times of vortexing and centrifugation were optimized. Under optimized conditions, the limits of detection (LOD) and quantification (LOQ) were 0.02 µg l -1 and 0.08 µg l -1 respectively. OTA extraction recovery by SALLE was approximately 90% (0.2 µg l -1 ). Furthermore, the methodology was in agreement with EU Directive requirements and was successfully applied for analysis of beer samples.

Background radiation dose of dumpsites in Ota and Environs

NASA Astrophysics Data System (ADS)

Usikalu, M. R.; Ola, O. O.; Achuka, J. A.; Babarimisa, I. O.; Ayara, W. A.

2017-05-01

In-situ measurement of background radiation dose from selected dumpsites in Ota and its environs was done using Radialert Nuclear Radiation Monitor (Digilert 200). Ten measurements were taken from each dumpsite. The measured background radiation range between 0.015 mRhr-1 for AOD and 0.028 mRhr-1 for SUS dumpsites. The calculated annual equivalent doses vary between 1.31 mSvyr-1 for AOD and 2.28 mSv/yr for SUS dumpsites. The air absorbed dose calculated ranged from 150 nGyhr-1 to 280 nGy/hr for AOD and SUS dumpsites respectively with an average value of 217 nGyhr-1 for all the locations. All the estimated parameters were higher than permissible limit set for background radiation for the general public. Conclusively, the associated challenge and radiation burden posed by the wastes on the studied locations and scavengers is high. Therefore, there is need by the regulatory authorities to look into the way and how waste can be properly managed so as to alleviate the effects on the populace leaving and working in the dumpsites vicinity.

Studies on some feed additives and materials giving partial protection against the suppressive effect of ochratoxin A on egg production of laying hens.

PubMed

Stoev, Stoycho D

2010-06-01

The protective effects of various feed supplements against the harmful effect of ochratoxin A on egg production and sexual maturation of two-weeks old Plymouth Rock female chicks designed for laying hens were studied. A significant protective effect of the feed additives or materials: water extract of artichoke (WEA), sesame seed (SS), Roxazyme-G (RG) and l-beta phenylalanine (PHE) against the suppressive effect of ochratoxin A (OTA) on egg production of laying hens was found. A similar protection was also seen on the toxic effect of OTA on various internal organs of the same hens. A significant protection was found against the decrease of the weight or the quantity of eggs as well as against the delay of the beginning of the laying period of chicks, both of which were provoked by ochratoxin A. These protective effects were strongest in chicks treated with SS or WEA, but were slightest in chicks treated with l-beta PHE. Copyright 2009 Elsevier Ltd. All rights reserved.

[The prevention of Ochratossina A (OTA A) in the wine].

PubMed

Alonzo, Elena; Cafarella, Nicola; Duplicato, Giovanni; Maugeri, Antonio; Platania, Francesco; Raciti, Claudio; Fardella, Maristella

2008-01-01

The expansion of global market has recalled more and more the attention of the researchers on the presence of mycotoxins in the foodstuff. Trying to limit the damages to the health and the correlated economic losses the European Community has legislated fixing more restrictive limits for the presence of mycotoxins in the single food products; and, specifically the limits of presence of Ochratoxin A (OTA A) in the wines have been established by the rule EEC 123 / 2005. With the purpose to prevent the formation of OTA á in the wine (from the grape to the bottled product), has been conducted, a study to compare the different techniques currently used, as the Good Agricultural Practices (BPA), the Good Practices of Manufacture (BPF) and the Good Practices of storage (BPS) with the system of Hazard Analysis Critical Control Points (HACCP), nowadays used only from the begin of the phase of processing of the agricultural products. It results that, concerning the BPAs, the application of the System HACCP on the primary production would bring neither some innovation nor qualitative improvement. The comparison among BPF, BPS and HACCP, confirms, instead, as the HACCP allows to individualize a series of additional critical points worth of attention during the process and maintenance of the grapes. Such result is in agreement with the new community rule 852/2004, which, also because the difficulties in the application of the HACCP to the primary production, confirm the necessity to follow, on the field, the hygienic respect of the sanitary measures (see attached one artt. 5- 6). This involves the necessity of an increasing integration and cooperation among different professional workers (as hygienist and agronomist). That kind of cooperation is already in use (from year 2003), within the "progetto fito", started by the AUSL 3 of Catania, with the coordination of the Service Hygiene Food stuff and Nutrition (SIAN).

When do anterior external or internal fixators provide additional stability in an unstable (Tile C) pelvic fracture? A biomechanical study.

PubMed

Mcdonald, E; Theologis, A A; Horst, P; Kandemir, U; Pekmezci, M

2015-12-01

This study aimed at evaluating the additional stability that is provided by anterior external and internal fixators in an unstable pelvic fracture model (OTA 61-C). An unstable pelvic fracture (OTA 61-C) was created in 27 synthetic pelves by making a 5-mm gap through the sacral foramina (posterior injury) and an ipsilateral pubic rami fracture (anterior injury). The posterior injury was fixed with either a single iliosacral (IS) screw, a single trans-iliac, trans-sacral (TS) screw, or two iliosacral screws (S1S2). Two anterior fixation techniques were utilized: external fixation (Ex-Fix) and supra-acetabular external fixation and internal fixation (In-Fix); supra-acetabular pedicle screws connected with a single subcutaneous spinal rod. The specimens were tested using a nondestructive single-leg stance model. Peak-to-peak (P2P) displacement and rotation and conditioning displacement (CD) were calculated. The Ex-Fix group failed in 83.3 % of specimens with concomitant single-level posterior fixation (Total: 15/18-7 of 9 IS fixation, 8 of 9 TS fixation), and 0 % (0/9) of specimens with concomitant two-level (S1S2) posterior fixation. All specimens with the In-Fix survived testing except for two specimens treated with In-Fix combined with IS fixation. Trans-sacral fixation had higher pubic rotation and greater sacral and pubic displacement than S1S2 (p < 0.05). Rotation of the pubis and sacrum was not different between In-Fix constructs combined with single-level IS and TS fixation. In this model of an unstable pelvic fracture (OTA 61-C), anterior fixation with an In-Fix was biomechanically superior to an anterior Ex-Fix in the setting of single-level posterior fixation. There was no biomechanical difference between the In-Fix and Ex-Fix when each was combined with two levels of posterior sacral fixation.

Effect of fragmentary displacement and morphology in the treatment of comminuted femoral shaft fractures with an intramedullary nail.

PubMed

Lin, Shih-Jie; Chen, Chi-Lung; Peng, Kuo-Ti; Hsu, Wei-Hsiu

2014-04-01

Our study aimed to determine whether the displacement and morphology of a fragment in femur fracture with Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association/32-B/32-C (AO/OTA/32-B/32-C) classification affect the outcomes following closed reduction and internal fixation with an interlocking nail. This was a retrospective study. The study was conducted at a Level III trauma centre. A total of 50 consecutive patients presenting femoral shaft fracture with AO/OTA-type 32-B/32-C were included in the present study. Patients were divided into two groups according to the displacement of the fragments. In the large displacement group, patients were further subgrouped according to whether a reversed morphology of the fragment was present. The radiographic union score of femur (RUSF), the mean union time and the re-operation rate were assessed. The union rate of small- and large-gap groups at 12 months postoperatively was 75.9% and 21.1%, respectively (p=0.000). The mean union time of those union cases in these two groups was 7.8 and 13.0 months, respectively (p=0.000). The union rate of the non-reversed and reversed groups at 12 months postoperatively was 30% and 11.1%, respectively (p=0.179). The mean RUSF at 12 months in the non-reversed and reversed groups was 8.8 and 8.3, respectively (p=0.590). However, we found that patients presenting a reversed fragment had an increased risk of more than one re-operation (p=0.030). A fragmentary displacement of >1cm in AO/OTA-type 32-B/32-C femoral shaft fracture after nailing affected bone healing. Among the large-gap group patients, an unreduced reverse fragment presented a negative prognostic factor for re-operation. Prognostic level III. Copyright © 2013 Elsevier Ltd. All rights reserved.

Mycotoxin monitoring for commercial foodstuffs in Taiwan.

PubMed

Chen, Ming-Tzai; Hsu, Yuan-Hsin; Wang, Tzu-Sui; Chien, Shi-Wern

2016-01-01

Mycotoxins are toxic food contaminants that are naturally produced by certain fungi. They induce negative effects on human health by making food unsafe for consumption. In this study, analyses were performed to determine the levels and incidence of aflatoxins (AFs) in peanut products, tree nuts, spices, and Coix seeds; ochratoxin A (OTA) in wheat and roasted coffee, as well as OTA and AFs in rice; and citrinin (CIT) in red yeast rice (RYR) products. A total of 712 samples from nine different food categories were collected between 2012 and 2013. The samples were analyzed over 2 years for AFs, OTA, and CIT by methods recommended by the Ministry of Health and Welfare. These official analytical methods were extensively validated in-house and through interlaboratory trials. The analytical values of suspected contaminated specimens were confirmed by liquid chromatography - tandem mass spectrometry analysis to identify the specific mycotoxin present in the sample. We show that 689 samples (96.8%) complied with the regulations set by the Ministry of Health and Welfare. AFs were found in four peanut-candy products, one peanut-flour product, one pistachio product, one Sichuan-pepper product, and one Coix seed product. All had exceeded the maximum levels of 15 parts per billion for peanut and 10 parts per billion for other food products. Furthermore, 14 RYR samples contained CIT above 5 parts per million, and one RYR tablet exceeded the maximum amount allowed. Instances of AFs in substandard Sichuan pepper and Coix seeds were first detected in Taiwan. Measures were taken by the relevant authorities to remove substandard products from the market in order to decrease consumer exposure to mycotoxin. Border control measures were applied to importing food commodities with a higher risk of mycotoxin contamination, such as peanut, Sichuan pepper, and RYR products. Declining trends were observed in the noncompliance rate of AFs in peanut products, as well as that of CIT in RYR raw materials monitored from 2010 to 2013. Copyright © 2015. Published by Elsevier B.V.

Arabidopsis thaliana defense response to the ochratoxin A-producing strain (Aspergillus ochraceus 3.4412).

PubMed

Hao, Junran; Wu, Weihong; Wang, Yan; Yang, Zhuojun; Liu, Yang; Lv, Yangjun; Zhai, Yanan; Yang, Jing; Liang, Zhihong; Huang, Kunlun; Xu, Wentao

2015-05-01

OTA-producing strain Aspergillus ochraceus induced necrotic lesions, ROS accumulation and defense responses in Arabidopsis . Primary metabolic and defense-related proteins changed in proteomics. Ascorbate-glutathione cycle and voltage-dependent anion-selective channel proteins fluctuated. Mycotoxigenic fungi, as widespread contaminants by synthesizing mycotoxins in pre-/post-harvest infected plants and even stored commercial cereals, could usually induce plant-fungi defense responses. Notably, ochratoxin A (OTA) is a nephrotoxic, hepatotoxic, teratogenic, immunotoxic and phytotoxic mycotoxin. Herein, defense responses of model system Arabidopsis thaliana detached leaves to infection of Aspergillus ochraceus 3.4412, an OTA high-producing strain, were studied from physiological, proteomic and transcriptional perspectives. During the first 72 h after inoculation (hai), the newly formed hypersensitive responses-like lesions, decreased chlorophyll content, accumulated reactive oxygen species and upregulated defense genes expressions indicated the defense response was induced in the leaves with the possible earlier motivated jasmonic acid/ethylene signaling pathways and the later salicylic acid-related pathway. Moreover, proteomics using two-dimensional gel electrophoresis 72 hai showed 16 spots with significantly changed abundance and 13 spots corresponding to 12 unique proteins were successfully identified by MALDI-TOF/TOF MS/MS. Of these, six proteins were involved in basic metabolism and four in defense-related processes, which included glutathione-S-transferase F7, voltage-dependent anion-selective channel protein 3 (VDAC-3), osmotin-like protein OSM34 and blue copper-binding protein. Verified from proteomic and/or transcriptional perspectives, it is concluded that the primary metabolic pathways were suppressed with the ascorbate-glutathione cycle fluctuated in response to A. ochraceus and the modulation of VDACs suggested the possibility of structural damage and dysfunction of mitochondria in the process. Taken together, these findings exhibited a dynamic overview of the defense responses of A. thaliana to A. ochraceus and provided a better insight into the pathogen-resistance mechanisms in plants.

In vitro exposure of Penicillium mycotoxins with or without a modified yeast cell wall extract (mYCW) on bovine macrophages (BoMacs).

PubMed

Oh, Se-Young; Quinton, V Margaret; Boermans, Herman J; Swamy, H V L N; Karrow, Niel A

2015-11-01

Penicillium mycotoxins (PMs) are contaminants that are frequently found in grain or crop-based silage for animal feed. Previously, we have characterized the potential immunotoxicity of the following PMs: citrinin (CIT), ochratoxin A (OTA), patulin (PAT), mycophenolic acid (MPA), and penicillic acid (PA) by using a bovine macrophage cell line (BoMacs). In the present study, cell proliferation was used as a bioassay endpoint to evaluate the efficacy of a modified yeast cell wall extract (mYCW), for preventing PM toxicity under various in vitro conditions such as the following: pH (3, 5, 7), incubation time (1, 2, 4, 6 h), percentage of mYCW (0.05, 0.1, 0.2, 0.5, 1.0 %), and PM concentration. mYCW was most effective in preventing the toxicity of 12.88 and 25.8 μM OTA at pH 3.0 (p < 0.0001), regardless of incubation time (p < 0.0001) and the percentage of mYCW (p < 0.0001). An incubation time of 6 h (p < 0.05) or 0.5 and 1.0 % mYCW (p < 0.0001) significantly improved the efficacy of mYCW for preventing CIT toxicity. In contrast, 0.5 and 1.0 % of mYCW appeared to exacerbate the PAT toxicity (p < 0. 0001). This effect on PAT toxicity was constantly observed with higher PAT concentrations, and it reached significance at a concentration of 0.70 μM (p < 0.0001). mYCW had no effect on PA toxicity. These results suggest that mYCW may reduce OTA toxicity and, to some extent, CIT toxicity at pH 3.0. Although PAT toxicity was increased by mYCW treatment, PAT is readily degraded during heat treatment and may therefore be dealt with using other preventative measures.

Finding a Balance: Computer Software, Intellectual Property and the Challenge of Technological Change.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. Office of Technology Assessment.

This report, prepared by the Office of Technological Assessment (OTA) in response to a request from the House Committee on the Judiciary, examines the rapid and complex technological changes and trends in computer software technologies and their possible effects on the nation's intellectual property system. The three policy issues identified are:…

Women in Development. Farm House Dialogue (7th, Ota, Nigeria, November 17-19, 1989).

ERIC Educational Resources Information Center

Africa Leadership Forum.

This document summarizes discussions at an invitational workshop on women in Nigeria. The discussion centered on overcoming sex bias and discrimination in all areas of life so that women could contribute to the national development effort. The following broad topics were discussed: (1) cultural attitudes that discourage the education of women; (2)…

Non-native plants and adaptive collaborative approaches to ecosystem restoration [Chapter 8

Treesearch

John Schelhas; James H. Miller; Jeanne C. Chambers

2012-01-01

Non-native invasive plant species (NNIPS) pose a serious socio-ecological challenge due to their potential to replace and damage critical human-sustaining ecosystems (OTA 1993; Mack et al. 2000; Pimentel 2002). The impacts of non-native species are widespread and significant - altering ecosystem structure and function, threatening other species, and imposing human...

Leadership for Development. Farm House Dialogue (1st, Ota, Nigeria, May 13-14, 1988).

ERIC Educational Resources Information Center

Africa Leadership Forum.

This document summarizes discussions at an invitational workshop on leadership for development in Nigeria. The following views on the essence of leadership were expressed: (1) the majority of current leaders tend to be selfish, self-centered, and incapable of performing their jobs effectively; (2) most current leaders have impeded the growth of…

Labour and Development. Farm House Dialogue (5th, Ota, Nigeria, July 7-9, 1989).

ERIC Educational Resources Information Center

Africa Leadership Forum.

This document summarizes discussions at an invitational workshop on labor development in Nigeria. The discussion centered on the need to promote an individual work ethic and to improve the quality of life of the average worker. The following broad topics were discussed: (1) the negative effect of colonialism on individual productivity and the lack…

The OTA report on harmful nonindigenous species

Treesearch

Phyllis N. Windle

1998-01-01

At least 4,500 species of foreign origin have established free-living populations in the United States, of which about 15% cause severe economic or environmental harm. Between 1906 and 1991, just 79 species caused an estimated $97 billion in losses. Virtually every economic sector and area of the country is affected, with some of the biggest problems in the east....

The Natural World as Colonized Other(s): Educational Implications

ERIC Educational Resources Information Center

Blenkinsop, Sean; Piersol, Laura; Sitka-Sage, Michael D.; Ho, Yi Chien Jade

2016-01-01

This paper begins with two parallel, although not identical, images. The first is of Ota Benga, a Congolese "pygmy" brought to the St. Louis World Fair in 1904 and displayed in a cage for the entertainment of the visiting public. The second is of a Red Maple tree in a large concrete pot on the campus of Simon Fraser University on the…

Natural Co-Occurrence of Mycotoxins in Foods and Feeds and Their in vitro Combined Toxicological Effects.

PubMed

Smith, Marie-Caroline; Madec, Stéphanie; Coton, Emmanuel; Hymery, Nolwenn

2016-03-26

Some foods and feeds are often contaminated by numerous mycotoxins, but most studies have focused on the occurrence and toxicology of a single mycotoxin. Regulations throughout the world do not consider the combined effects of mycotoxins. However, several surveys have reported the natural co-occurrence of mycotoxins from all over the world. Most of the published data has concerned the major mycotoxins aflatoxins (AFs), ochratoxin A (OTA), zearalenone (ZEA), fumonisins (FUM) and trichothecenes (TCTs), especially deoxynivalenol (DON). Concerning cereals and derived cereal product samples, among the 127 mycotoxin combinations described in the literature, AFs+FUM, DON+ZEA, AFs+OTA, and FUM+ZEA are the most observed. However, only a few studies specified the number of co-occurring mycotoxins with the percentage of the co-contaminated samples, as well as the main combinations found. Studies of mycotoxin combination toxicity showed antagonist, additive or synergic effects depending on the tested species, cell model or mixture, and were not necessarily time- or dose-dependent. This review summarizes the findings on mycotoxins and their co-occurrence in various foods and feeds from all over the world as well as in vitro experimental data on their combined toxicity.

Natural Co-Occurrence of Mycotoxins in Foods and Feeds and Their in vitro Combined Toxicological Effects

PubMed Central

Smith, Marie-Caroline; Madec, Stéphanie; Coton, Emmanuel; Hymery, Nolwenn

2016-01-01

Some foods and feeds are often contaminated by numerous mycotoxins, but most studies have focused on the occurrence and toxicology of a single mycotoxin. Regulations throughout the world do not consider the combined effects of mycotoxins. However, several surveys have reported the natural co-occurrence of mycotoxins from all over the world. Most of the published data has concerned the major mycotoxins aflatoxins (AFs), ochratoxin A (OTA), zearalenone (ZEA), fumonisins (FUM) and trichothecenes (TCTs), especially deoxynivalenol (DON). Concerning cereals and derived cereal product samples, among the 127 mycotoxin combinations described in the literature, AFs+FUM, DON+ZEA, AFs+OTA, and FUM+ZEA are the most observed. However, only a few studies specified the number of co-occurring mycotoxins with the percentage of the co-contaminated samples, as well as the main combinations found. Studies of mycotoxin combination toxicity showed antagonist, additive or synergic effects depending on the tested species, cell model or mixture, and were not necessarily time- or dose-dependent. This review summarizes the findings on mycotoxins and their co-occurrence in various foods and feeds from all over the world as well as in vitro experimental data on their combined toxicity. PMID:27023609

Simultaneous detection of multiple mycotoxins in broiler feeds using a liquid chromatography tandem-mass spectrometry

PubMed Central

KONGKAPAN, Jutamart; POAPOLATHEP, Saranya; ISARIYODOM, Supaporn; KUMAGAI, Susumu; POAPOLATHEP, Amnart

2015-01-01

Mycotoxins are secondary fungal metabolites that are typically present in grain and feed ingredients used for animal feeds. An analytical method using LC-ESI-MS/MS was developed to quantify nine mycotoxins, consisting of aflatoxin B1 (AFB1), AFB2, AFG1, AFG2, T-2 toxin, deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEA) and ochratoxin A (OTA) in broiler feeds. In total, 100 samples of broiler feeds were collected from poultry farms in Central Thailand. The survey found that AFB1 and ZEA were the most prevalent mycotoxins in the feed samples at percentages of 93% and 63%, respectively. The limit of detections (LODs) of investigated mycotoxins was 0.20–0.78 ng/g. AFB2, DON, AFG1, NIV and T-2 toxin were also detectable at low contamination levels with percentages of 20%, 9%, 7%, 5% and 1%, respectively, whereas OTA and AFG2 were not detected in any of the feed samples. These results suggest that there is a very low level of risk of the exposure to mycotoxins in feeds obtained from broiler farms in Central Thailand. PMID:26477362

TiO2 Nanolayer-Enhanced Fluorescence for Simultaneous Multiplex Mycotoxin Detection by Aptamer Microarrays on a Porous Silicon Surface.

PubMed

Liu, Rui; Li, Wei; Cai, Tingting; Deng, Yang; Ding, Zhi; Liu, Yan; Zhu, Xuerui; Wang, Xin; Liu, Jie; Liang, Baowen; Zheng, Tiesong; Li, Jianlin

2018-05-02

A new aptamer microarray method on the TiO 2 -porous silicon (PSi) surface was developed to simultaneously screen multiplex mycotoxins. The TiO 2 nanolayer on the surface of PSi can enhance the fluorescence intensity 14 times than that of the thermally oxidized PSi. The aptamer fluorescence signal recovery principle was performed on the TiO 2 -PSi surface by hybridization duplex strand DNA from the mycotoxin aptamer and antiaptamer, respectively, labeled with fluorescence dye and quencher. The aptamer microarray can simultaneously screen for multiplex mycotoxins with a dynamic linear detection range of 0.1-10 ng/mL for ochratoxin A (OTA), 0.01-10 ng/mL for aflatoxins B 1 (AFB 1 ), and 0.001-10 ng/mL for fumonisin B 1 (FB 1 ) and limits of detection of 15.4, 1.48, and 0.21 pg/mL for OTA, AFB 1 , and FB 1 , respectively. The newly developed method shows good specificity and recovery rates. This method can provide a simple, sensitive, and cost-efficient platform for simultaneous screening of multiplex mycotoxins and can be easily expanded to the other aptamer-based protocol.

Is Gamma Radiation Suitable to Preserve Phenolic Compounds and to Decontaminate Mycotoxins in Aromatic Plants? A Case-Study with Aloysia citrodora Paláu.

PubMed

Pereira, Eliana; Barros, Lillian; Antonio, Amilcar L; Cabo Verde, Sandra; Santos-Buelga, Celestino; Ferreira, Isabel C F R; Rodrigues, Paula

2017-02-23

This study aimed to determine the effect of gamma radiation on the preservation of phenolic compounds and on decontamination of dry herbs in terms of ochratoxin A (OTA) and aflatoxin B1 (AFB1), using Aloysia citrodora Paláu as a case study. For this purpose, artificially contaminated dry leaves were submitted to gamma radiation at different doses (1, 5, and 10 kGy; at dose rate of 1.7 kGy/h). Phenolic compounds were analysed by HPLC-DAD-ESI/MS and mycotoxin levels were determined by HPLC-fluorescence. Eleven phenolic compounds were identified in the samples and despite the apparent degradation of some compounds (namely verbasoside), 1 and 10 kGy doses point to a preservation of the majority of the compounds. The mean mycotoxin reduction varied between 5.3% and 9.6% for OTA and from 4.9% to 5.2% for AFB1. It was not observed a significant effect of the irradiation treatments on mycotoxin levels, and a slight degradation of the phenolic compounds in the irradiated samples was observed.

Brain’s DNA Repair Response to Neurotoxicants

DTIC Science & Technology

2005-07-01

it is possible that OTA exposure may impact on this ability of this structure to maintain its functional integrity over time. Indeed it is known...Gordon et al., 2004). In light of the critical role played by hippocampus in cognitive function, and the importance of neurogenesis in this structure ...uncompetitive inhibitorof both succinate-cytochrome c reductase and succinate dehydrogenase while sparing cytochrome oxidase and NADH dehydrogenase

Joint Force Quarterly. Issue 45, 2d Quarter 2007

DTIC Science & Technology

2007-01-01

liberal institutional explana- tion for alliances, Ota is really describing how the Japan Self - Defense Forces (JSDF) worked to share the risk and try...training, intelligence, and civil affairs) the armed forces of the Philippines in their operations against Abu Sayyaf, a self -declared militant...was preoccupied with domestic difficulties and disasters (largely self -inflicted) and the daunting demands of economic development. But with the

Environmental contaminants in food. Volume II-part a: working papers. I. Priority setting of toxic substances for guiding monitoring programs. II. Five case studies of environmental food contamination

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This volume contains working papers written for Office of Technology Assessment (OTA) to assist in preparation of the report Environmental Contaminants in Food. The contents include: (1) Priority setting of toxic substances for guiding monitoring programs; and (2) Five case studies of environmental food contamination.

Director, Operational Test and Evaluation FY 2014 Annual Report

DTIC Science & Technology

2015-01-01

Federal Departments and Agencies. Mitigation measures such as curtailment of wind turbine operations during test periods, identification of alternative...impact of wind turbines on ground-based and airborne radars, and this investment may help mitigate interference of wind turbines with test range...Frequency Active (SURTASS CLFA) Test Plan Tactical Unmanned Aircraft System Tactical Common Data Link (Shadow) FOT&E OTA Test Plan Tempest Wind 2014

Director, Operational Test and Evaluation

DTIC Science & Technology

2007-12-01

important, and all – collectively – are necessary to properly set requirements, incentivize industry, oversee system design and development, and finally...evaluation planning which defines testing required for all system-level evaluation. • Enable access to all system-level test data by government DT...responsible for sustainment cost estimates, and with the OTAs, to contribute relevant data. As with all new missions, there is a question of resources

The HORUS Observatory - A Next Generation 2.4m UV-Optical Mission To Study Planetary, Stellar And Galactic Formation

NASA Astrophysics Data System (ADS)

Scowen, Paul A.; SDT, HORUS

2013-01-01

The High-ORbit Ultraviolet-visible Satellite (HORUS) is a 2.4-meter class UV-optical space telescope that will conduct a comprehensive and systematic study of the astrophysical processes and environments relevant for the births and life cycles of stars and their planetary systems, to investigate and understand the range of environments, feedback mechanisms, and other factors that most affect the outcome of the star and planet formation process. To do so, HORUS will provide 100 times greater imaging efficiency and more than 10 times greater UV spectroscopic sensitivity than has existed on the Hubble Space Telescope (HST). The HORUS mission will contribute vital information on how solar systems form and whether habitable planets should be common or rare. It also will investigate the structure, evolution, and destiny of galaxies and universe. This program relies on focused capabilities unique to space that no other planned NASA mission will provide: near-UV/visible (200-1075nm) wide-field, diffraction-limited imaging; and high-sensitivity, high-resolution UV (100-170nm) spectroscopy. The core HORUS design will provide wide field of view imagery and high efficiency point source FUV spectroscopy using a novel combination of spectral selection and field sharing. The HORUS Optical Telescope Assembly (OTA) design is based on modern light weight mirror technology with a faster primary mirror to shorten the overall package and thereby reduce mass. The OTA uses a three-mirror anastigmat configuration to provide excellent imagery over a large FOV - and is exactly aligned to use one of the recently released f/1.2 NRO OTAs as part of its design. The UV/optical Imaging Cameras use two 21k x 21k Focal Plane Arrays (FPAs). The FUV spectrometer uses cross strip anode based MCPs. This poster presents results from a 2010 design update requested by the NRC Decadal Survey, and reflects updated costs and technology to the original 2004 study. It is now one of the most mature 2.4m UVOIR observatory designs in NASA’s portfolio.

CFRP composite optical telescope assembly for the 1 m ULTRA project

NASA Astrophysics Data System (ADS)

Martin, Robert N.; Romeo, Robert C.

2006-06-01

The focus of the ULTRA Project is to develop and test Ultra-Lightweight Technology for Research applications in Astronomy. The ULTRA project is a collaborative effort involving the private firm Composite Mirror Applications, Inc (CMA) and 3 universities: University of Kansas, San Diego State University, and Dartmouth College. Funding for ULTRA is predominately from a NSF three year MRI program grant to CMA and KU with additional support from CMA, KU and SDSU. The goal of the ULTRA program is to demonstrate that a viable alternative exists to traditional glass mirror and steel telescope technology by designing, fabricating and testing a research telescope constructed from carbon fiber reinforced plastic (CFRP) materials. In particular, a 1m diameter, Cassegrain telescope optics set and optical tube assembly (OTA) are being designed and fabricated by CMA. The completed telescope will be deployed at SDSU's Mt Laguna Observatory in a refurbished structure (new dome and mount provided via KU and SDSU). We expect that a successful completion and testing of this project will lead to future use of CFRP technology in larger telescopes and segmented telescopes. This paper describes the OTA (optical tube assembly) that has been developed for the ULTRA project. The mirror technology is described in another paper in this conference. A poster describes the ULTRA project overview in more detail.

Mycobiota and Natural Incidence of Aflatoxins, Ochratoxin A, and Citrinin in Indian Spices Confirmed by LC-MS/MS

PubMed Central

Jeswal, Punam; Kumar, Dhiraj

2015-01-01

Nine different Indian spices (red chilli, black pepper, turmeric, coriander, cumin, fennel, caraway, fenugreek, and dry ginger) commonly cultivated and highly used in India were analysed for natural occurrence of toxigenic mycoflora and aflatoxins (AFs), ochratoxin A (OTA), and citrinin (CTN) contamination. Aspergillus flavus and Aspergillus niger were the most dominant species isolated from all types of spices. Red chilli samples were highly contaminated with aflatoxins (85.4%) followed by dry ginger (77.7%). 56% Aspergillus flavus from red chilli and 45% Aspergillus ochraceus from black pepper were toxigenic and produced aflatoxins and ochratoxin A, respectively. Qualitative detection and quantitative detection of mycotoxins in spices were analyzed by ELISA and further confirmed by LC-MS/MS. Penicillium citrinum produced citrinin in red chilli, black pepper, coriander, cumin, fenugreek, and dry ginger samples. The highest amount of AFs was found in red chilli (219.6 ng/g), OTA was in black pepper (154.1 ng/g), and CTN was in dry ginger samples (85.1 ng/g). The results of this study suggest that the spices are susceptible substrate for growth of mycotoxigenic fungi and further mycotoxin production. This is the first report of natural occurrence of citrinin in black pepper and dry ginger from India. PMID:26229535

Effect of ultraviolet radiation A and B on growth and mycotoxin production by Aspergillus carbonarius and Aspergillus parasiticus in grape and pistachio media.

PubMed

García-Cela, Esther; Marin, Sonia; Sanchis, Vicente; Crespo-Sempere, Ana; Ramos, Antonio J

2015-01-01

The effects of two exposure times per day (6 and 16 h) of UV-A or UV-B radiation, combined with dark and dark plus light incubation periods during 7-21 d on fungal growth and mycotoxins production of Aspergillus species were studied. Aspergillus carbonarius and Aspergillus parasiticus were inoculated on grape and pistachio media under diurnal and nocturnal temperatures choosing light photoperiod according to harvest conditions of these crops in Spain. Ultraviolet irradiation had a significant effect on A. carbonarius and A. parasiticus colony size (diameter, biomass dry weight, and colony density) and mycotoxin accumulation, although intraspecies differences were observed. Inhibition of A. carbonarius fungal growth decreased when exposure time was reduced from 16 h to 6 h, but this was not always true for ochratoxin A (OTA) production. OTA reduction was higher under UV-A than UV-B radiation and the reduction increased along time conversely to the aflatoxins (AFs). Aflatoxin B1 (AFB1) was the main toxin produced by A. parasiticus except in the UV-B light irradiated colonies which showed a higher percentage of AFG than AFB. Morphological changes were observed in colonies grown under UV-B light. Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Homogeneous assay of target molecules based on chemiluminescence resonance energy transfer (CRET) using DNAzyme-linked aptamers.

PubMed

Mun, Hyoyoung; Jo, Eun-Jung; Li, Taihua; Joung, Hyou-Arm; Hong, Dong-Gu; Shim, Won-Bo; Jung, Cheulhee; Kim, Min-Gon

2014-08-15

We have designed a single-stranded DNAzyme-aptamer sensor for homogeneous target molecular detection based on chemiluminescence resonance energy transfer (CRET). The structure of the engineered single-stranded DNA (ssDNA) includes the horseradish peroxidase (HRP)-like DNAzyme, optimum-length linker (10-mer-length DNA), and target-specific aptamer sequences. A quencher dye was modified at the 3' end of the aptamer sequence. The incorporation of hemin into the G-quadruplex structure of DNAzyme yields an active HRP-like activity that catalyzes luminol to generate a chemiluminescence (CL) signal. In the presence of target molecules, such as ochratoxin A (OTA), adenosine triphosphate (ATP), or thrombin, the aptamer sequence was folded due to the formation of the aptamer/analyte complex, which induced the quencher dye close to the DNAzyme structure. Consequently, the CRET occurred between a DNAzyme-catalyzed chemiluminescence reaction and the quencher dye. Our results showed that CRET-based DNAzyme-aptamer biosensing enabled specific OTA analysis with a limit of detection of 0.27ng/mL. The CRET platform needs no external light source and avoids autofluorescence and photobleaching, and target molecules can be detected specifically and sensitively in a homogeneous manner. Copyright © 2014 Elsevier B.V. All rights reserved.

Ecophysiological characterization of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger isolated from grapes in Spanish vineyards.

PubMed

García-Cela, E; Crespo-Sempere, A; Ramos, A J; Sanchis, V; Marin, S

2014-03-03

The aim of this study was to evaluate the diversity of black aspergilli isolated from berries from different agroclimatic regions of Spain. Growth characterization (in terms of temperature and water activity requirements) of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger was carried out on synthetic grape medium. A. tubingensis and A. niger showed higher maximum temperatures for growth (>45 °C versus 40-42 °C), and lower minimum aw requirements (0.83 aw versus 0.87 aw) than A. carbonarius. No differences in growth boundaries due to their geographical origin were found within A. niger aggregate isolates. Conversely, A. carbonarius isolates from the hotter and drier region grew and produced OTA at lower aw than other isolates. However, little genetic diversity in A. carbonarius was observed for the microsatellites tested and the same sequence of β-tubulin gene was observed; therefore intraspecific variability did not correlate with the geographical origin of the isolates or with their ability to produce OTA. Climatic change prediction points to drier and hotter climatic scenarios where A. tubingensis and A. niger could be even more prevalent over A. carbonarius, since they are better adapted to extreme high temperature and drier conditions. Copyright © 2013 Elsevier B.V. All rights reserved.

Detection of the MW Transition Between Ortho and Para States

NASA Astrophysics Data System (ADS)

Kanamori, Hideto; Dehghani, Zeinab Tafti; Mizoguchi, Asao; Endo, Yasuki

2017-06-01

Thorough the detailed analysis of the hyperfine resolved rotational transitions, we have been pointed out that there exists not a little interaction between ortho and para states in the molecular Hamiltonian of S_2Cl_2. Using the ortho-para mixed molecular wavefunctions derived from the Hamiltonian, we calculated the transition moment and frequency of the ortho-para forbidden transitions in the cm- and mm-wave region, and picked up some promising candidate transitions for the spectroscopic detection. In the experiment, the S_2Cl_2 vapor with Ar buffer gas in a supersonic jet condition was used with FTMW spectrometer at National Chiao Tung University. As a result, seven hyperfine resolved rotational transitions in the cm-wave region were detected as the ortho-para transition at the predicted frequency within the experimental error range. The observed intensity was 10^{-3} smaller than that of an allowed transition, which is also consistent with the prediction. This is the first time the electric dipole transition between ortho and para states has been detected in a free isolated molecule. A. Mizoguchi, S. Ota, H. Kanamori, Y. Sumiyoshi, and Y. Endo, J. Mol. Spectrosc, 250, 86 (2008) Z. T. Dehghani, S. Ota, A. Mizoguchi and H. Kanamori, J. Phys. Chem. A, 117(39), 10041, (2013)

Multiplexed capillary microfluidic immunoassay with smartphone data acquisition for parallel mycotoxin detection.

PubMed

Machado, Jessica M D; Soares, Ruben R G; Chu, Virginia; Conde, João P

2018-01-15

The field of microfluidics holds great promise for the development of simple and portable lab-on-a-chip systems. The use of capillarity as a means of fluidic manipulation in lab-on-a-chip systems can potentially reduce the complexity of the instrumentation and allow the development of user-friendly devices for point-of-need analyses. In this work, a PDMS microchannel-based, colorimetric, autonomous capillary chip provides a multiplexed and semi-quantitative immunodetection assay. Results are acquired using a standard smartphone camera and analyzed with a simple gray scale quantification procedure. The performance of this device was tested for the simultaneous detection of the mycotoxins ochratoxin A (OTA), aflatoxin B1 (AFB1) and deoxynivalenol (DON) which are strictly regulated food contaminants with severe detrimental effects on human and animal health. The multiplexed assay was performed approximately within 10min and the achieved sensitivities of<40, 0.1-0.2 and<10ng/mL for OTA, AFB1 and DON, respectively, fall within the majority of currently enforced regulatory and/or recommended limits. Furthermore, to assess the potential of the device to analyze real samples, the immunoassay was successfully validated for these 3 mycotoxins in a corn-based feed sample after a simple sample preparation procedure. Copyright © 2017 Elsevier B.V. All rights reserved.

The Lisbon new international airport: The story of a decision-making process and the role of Strategic Environmental Assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Partidario, Maria R., E-mail: mrp@civil.ist.utl.p; Coutinho, Miguel, E-mail: miguel.coutinho@ua.p

2011-04-15

This is the brief story of a decision process and the role of Strategic Environmental Assessment in government political decision-making. Following a prolonged, and agitated, decision process, initiated in the 1960s, the Government of Portugal in 2005 took the final decision to build the new international airport of Lisbon at the controversial location of Ota, 40 km north of Lisbon. The detailed project design and EIA were started. However this decision would change in 2007 due to the challenge raised by a private sponsored study that identified an alternative location for the airport at Campo de Tiro de Alcochete (CTA).more » This new site, which had never been considered as an option before, appeared to avoid many of the problems that caused public controversy at the Ota site. The Government, pressured by this challenge, promoted a strategic comparative assessment between the two sites. The result of this study was the choice of CTA as the preferred location. This paper discusses this radical change in the decision from a socio-political perspective. It will highlight the relevance of Strategic Environmental Assessment (SEA), and the strategic and constructive approach it enables in mega-project decision-making.« less

Grape and environmental mycoflora monitoring in old, traditionally cultivated vineyards on Mount Etna, southern Italy.

PubMed

Oliveri, Cinzia; Bella, Patrizia; Tessitori, Matilde; Catara, Vittoria; La Rosa, Rosa

2017-01-01

Grape contamination by several fungal species occurs during a vineyard's preharvest and harvest. Agronomic management and microclimatic conditions can affect fungi occurrence and epidemiology, thus explaining qualitative differences in mycoflora composition, including the presence of phytopathogenic or mycotoxigenic fungi. In this study a two-year grape, air and soil mycoflora monitoring programme was undertaken in vineyards on Mount Etna (eastern Sicily, Italy). The mycoflora composition was investigated at pea berry and veraison phenological phases from air and soil and at ripening from sample grapes. Mycoflora in air and soil varied according to the phenological stage. In the air samples, penicillia were dominant over aspergilli at the pea berry phase, but their ratio was inverted at early veraison. Black aspergilli (BA) were isolated from the vine environment and grape samples, where BA were represented mainly by Aspergillus niger aggregate, which showed no or low ochratoxin A (OTA) production. Aspergillus carbonarius was either not identified or identified at low frequency, although most of the isolates produced OTA. Monitoring focused on the environmental mycoflora composition and highlighted the good health profile of various Sicilian autochthonous grape cultivars. In addition, data suggest that the lower relative humidity occurring at the highest altitudes reduces BA incidence. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Methods for Determining Aircraft Surface State at Lesser-Equipped Airports

NASA Technical Reports Server (NTRS)

Roach, Keenan; Null, Jody

2016-01-01

Tactical departure scheduling within a terminal airspace must accommodate a wide spectrum of surveillance and communication capabilities at multiple airports. The success of such a scheduler is highly dependent upon the knowledge of a departure's state while it is still on the surface. Airports within a common Terminal RAdar CONtrol (TRACON) airspace possess varying levels of surface surveillance infrastructure which directly impacts uncertainties in wheels-off times. Large airports have access to surface surveillance data, which is shared with the TRACON, while lesser-equipped airports still rely solely on controllers in Air Traffic Control Towers (Towers). Coordination between TRACON and Towers can be greatly enhanced when the TRACON controller has access to the surface surveillance and the associated decision-support tools at well-equipped airports. Similar coordination at lesser-equipped airports is still based on verbal communications. This paper investigates possible methods to reduce the uncertainty in wheels-off time predictions at the lesser-equipped airports through the novel use of Over-the-Air (OTA) data transmissions. We also discuss the methods and equipment used to collect sample data at lesser-equipped airports within a large US TRACON, as well as the data evaluation to determine if meaningful information can be extracted from it.

Mapping Our Genes: The Genome Projects: How Big, How Fast

DOE R&D Accomplishments Database

1988-04-01

For the past 2 years, scientific and technical journals in biology and medicine have extensively covered a debate about whether and how to determine the function and order of human genes on human chromosomes and when to determine the sequence of molecular building blocks that comprise DNA in those chromosomes. In 1987, these issues rose to become part of the public agenda. The debate involves science, technology, and politics. Congress is responsible for ?writing the rules? of what various federal agencies do and for funding their work. This report surveys the points made so far in the debate, focusing on those that most directly influence the policy options facing the US Congress. Congressional interest focused on how to assess the rationales for conducting human genome projects, how to fund human genome projects (at what level and through which mechanisms), how to coordinate the scientific and technical programs of the several federal agencies and private interests already supporting various genome projects, and how to strike a balance regarding the impact of genome projects on international scientific cooperation and international economic competition in biotechnology. The Office of Technology Assessment (OTA) prepared this report with the assistance of several hundred experts throughout the world.

Oceanography of the Grand Banks Region of Newfoundland, March 1974-October 1974.

DTIC Science & Technology

1978-07-01

or Hayes (1978). Newfoundland. Station 11649 was deleted . The Deep-sea reversing thermometer and salinity most dominant feature of this survey was...02 O.tA lOS1 1 51118 1. SEA W140401 UM 1(2*7* 00.41 2 10(261 24 LONG 046 54.0k HO" 13.4 AafiA 05 CL.M TIA CLITA 5(EATPHAR .. WIG 0il 651 A $QUA* $6

IDA/OSD R&M (Institute for Defense Analyses/Office of the Secretary of Defense Reliability and Maintainability) Study Bibliography.

DTIC Science & Technology

1983-08-01

30 -IOLW. c • o:,,tas z ".9’ IM moOm X-272 IDA... 30 -2 • . ,, ... .L.. . .i W . . .’ I".• : V.*.’’. ;, .. . ... ," ... ,. . - 4..; ,,, .,, R&M STUDY,. DOCUMENTS LIST ( by Subject )-.:,’.i AS OF: 22...DE60. Maintainability Standardization Document Program Plan, Revision 1, Draft, DoD, 30 April 1982. DE82. Acquisition and Management of

Technical Education in Nigeria: The Way Forward. Summary of Proceedings of the Workshop on Technical Education: A Foundation for a Healthy Economy (Ota, Ogun State of Nigeria, March 1-2, 1994).

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Paris (France).

This summary of proceedings includes papers from and about a workshop on technical education in Nigeria and the lessons Nigeria may gain by examining the vocational and technical education systems of Germany, the United States, Great Britain, and Japan. The following papers are included: "Foreword" (Iyorchia Ayu); "Introduction: A…

Review of the Environmental Protection Agency’s Common Sense Initiative (The National Shipbuilding Research Program)

DTIC Science & Technology

1996-03-01

Falls Church, VA 22042 Robert Yancey Jr., President Aahland Petroleum P.O. Box 391 Ashland KY 41114 ROSTER - PRINTING SECTOR SUBCOMMlTTEE, CSI Co...Regulatory Initiative Project Workgroup ChaiR: Rick Johns Statement of Project Objective: To explore auto specific concerns with the Title V...and Recycling Workgroup Chair: Rick Reibstein, Massachusetts OTA Solving the “Obscure Policy” Problem Statement of Project or Activity Objective: TO

Contamination Control Considerations for the Next Generation Space Telescope (NGST)

NASA Technical Reports Server (NTRS)

Wooldridge, Eve M.

1998-01-01

The NASA Space Science Program, in its ongoing mission to study the universe, has begun planning for a telescope that will carry on the Hubble Space Telescope's exploration. This telescope, the 'Next Generation Space Telescope' (NGST), will be 6-8 meters in diameter, will be radiatively cooled to 30-60 Kelvin in order to enable extremely deep exposures at near infrared wavelengths, and will operate for a lifetime of 5-10 years. The requirement will be to measure wavelengths from 1-5 microns, with a goal to measure wavelengths from 0.6-30 microns. As such, NGST will present a new contamination control challenge. The Goddard Space Flight Center (GSFC) performed one of three preliminary feasibility studies for the NGST, presenting a telescope with an 8 meter, deployable primary mirror and a deployable secondary mirror. The telescope would be radiatively cooled, with the optical telescope assembly (OTA) and the science instrument module (SIM) isolated from the warmer spacecraft support module (SSM). The OTA and the SIM would also be shielded from sunlight with an enormous, inflatable sun-shield. The GSFC telescope was designed for launch on an Atlas HAS, which would require launching the telescope in a stowed configuration, with the SSM, antennae, sun-shield, primary mirror 'petals', and secondary mirror deployed once on-orbit. The launch configuration and deployment scenario of an exposed telescope measuring near infrared and cooled to 30-60 K are the factors presenting contamination hazards to the NGST mission. Preliminary science requirements established are: less than 20% reflectance decrease on optical surfaces over the wavelength range, and less than 0.3% obscuration of optical surfaces. In order to meet these requirements, NGST must be built and launched with careful attention to contamination control. Initial contamination control design options include strict selecting of materials and baking out of hardware down to the component level, minimizing or eliminating exposure of the OTA to sunlight or earth albedo during deployment and early on-orbit operations, cleaning of the primary and secondary mirrors at the launch site, cleaning of the launch vehicle fairing, locating thrusters and vents on the warm side of the sun shield only, and the possibility of including a deployable cover if that is shown to be necessary.

Identification and mycotoxigenic capacity of fungi associated with pre- and postharvest fruit rots of pomegranates in Greece and Cyprus.

PubMed

Kanetis, Loukas; Testempasis, Stefanos; Goulas, Vlasios; Samuel, Stylianos; Myresiotis, Charalampos; Karaoglanidis, George S

2015-09-02

Pre- and postharvest fruit rots of fungal origin are an important burden for the pomegranate industry worldwide, affecting the produce both quantitatively and qualitatively. During 2013, local orchards were surveyed and 280 fungal isolates from Greece (GR) and Cyprus (CY) were collected from pomegranates exhibiting preharvest rot symptoms, and additional 153 isolates were collected postharvest from cold-stored fruit in GR. Molecular identification revealed that preharvest pomegranate fruit rots were caused predominately by species of the genera Aspergillus (Aspergillus niger and Aspergillus tubingensis) and Alternaria (Alternaria alternata, Alternaria tenuissima, and Alternaria arborescens). By contrast, postharvest fruit rots were caused mainly by Botrytis spp. and to a lesser extent by isolates of Pilidiella granati and Alternaria spp. Considering that a significant quota of the fungal species found in association with pomegranate fruit rots are known for their mycotoxigenic capacity in other crop systems, their mycotoxin potential was examined. Alternariol (AOH), alternariol monomethyl-ether (AME) and tentoxin (TEN) production was estimated among Alternaria isolates, whereas ochratoxin A (OTA) and fumonisin B2 (FB2) production was assessed within the black aspergilli identified. Overall in both countries, 89% of the Alternaria isolates produced AOH and AME in vitro, while TEN was produced only by 43.9%. In vivo production of AOH and AME was restricted to 54.2% and 31.6% of the GR and CY isolates, respectively, while none of the isolates produced TEN in vivo. Among black aspergilli 21.7% of the GR and 17.8% of the CY isolates produced OTA in vitro, while in vivo OTA was detected in 8.8% of the isolates from both countries. FB2 was present in vitro in 42.0% of the GR and 22.2% of the CY isolates, while in vivo the production was limited to 27.5% and 4.5% of the GR and the CY isolates, respectively. Our data imply that mycotoxigenic Alternaria and Aspergillus species not only constitute a significant subset of the fungal population associated with pomegranate fruit rots responsible for fruit deterioration, but also pose a potential health risk factor for consumers of pomegranate-based products. Copyright © 2015 Elsevier B.V. All rights reserved.

Green synthesis of nanosilver particles by Aspergillus terreus HA1N and Penicillium expansum HA2N and its antifungal activity against mycotoxigenic fungi.

PubMed

Ammar, H A M; El-Desouky, T A

2016-07-01

The aim of this study was to synthesize silver nanoparticles (AgNPs) by an eco-friendly and low-cost method using the fungi Aspergillus terreus HA1N and Penicillium expansum HA2N as an alternative to chemical procedures mostly requiring drastic experimental conditions emitting toxic chemical byproducts. Also, this study has been extended to evaluate the effect of AgNPs on the growth of some mycotoxigenic fungi and ochratoxin A (OTA) produced by Aspergillus ochraceus. The AgNPs have been characterized by UV-Visible Spectrophotometer, Dynamic Light Scattering (DLS), Fourier Transform Infrared Spectroscopy (FTIR) and Transmission Electron Microscope (TEM). The TEM analysis has revealed that the size of AgNPs ranged between 14 and 25 nm in the case of P. expansum and 10-18 nm in the case of A. terreus. The antifungal activity of AgNP colloids has indicated that the highest inhibition zone was detected with AgNPs synthesized by A. terreus HA1N against all tested fungi. The highest inhibition zone was detected with Aspergillus niger at concentrations 3 and 6 μg of AgNP solution (7·56 ± 0·38 and 11·3 ± 1·8 mm, respectively) while, A. ochraceus showed the maximum inhibition zone (16·33 ± 0·96 mm) at the concentration 9 μg of AgNPs synthesized by A. terreus. The results have also indicated that the AgNPs synthesized by A. terreus and P. expansum at the concentration 220 μg/100 ml media gave the highest reduction of OTA, where the percentages of reduction were 58·87 and 52·18% respectively. The smallest size AgNPs synthesized by A. terreus HA1N are better in their antifungal activity against all tested mycotoxigenic fungi than the largest one synthesized by P. expansum HA2N. This is the first study focused on using AgNPs in control of OTA production. © 2016 The Society for Applied Microbiology.

Pulsed Power Bibliography. Volume 1. Indices.

DTIC Science & Technology

1983-08-01

REPETITION RATES «e»7 A 100 KV, FAST, HIGH EHEROY. NONUNIFORM FIELD DISTORTION SWITCH MM CROWBARRIHO TECHNIGUE FOR HIGH-VOLTAGE CAPACITOR SAHKS...EMISSION IN THE ELECTRICAL EXPLOSION OF A THIH METAL FOIL • lair , O.T.A. 427) STATISTICAL TIME LAOS IN GAS DISCHARGE GAPS IRRADIATED WITH A...7 A 111 KV. FAST. HIGH ENERGY, NONUNIFORM FIELD DISTORTION SWITCH MM A 3 MA. ill KV FAST CAPACITOR IANK FOR A SHOCK-HEATED TORUS 7217 A LOW

MALDI-Imaging Mass Spectrometry of Ochratoxin A and Fumonisins in Mold-Infected Food.

PubMed

Hickert, Sebastian; Cramer, Benedikt; Letzel, Matthias C; Humpf, Hans-Ulrich

2016-09-06

Mycotoxins are toxic secondary metabolites produced by various fungi. Their distribution within contaminated material is of high interest to obtain insight into infection mechanisms and the possibility of reducing contamination during food processing. Various vegetable foodstuffs were infected with fungi of the genera Fusarium and Aspergillus. The localization of the produced mycotoxins was studied by matrix assisted laser desorption ionization time of flight imaging mass spectrometry (MALDI-MSI) of cryosections obtained from infected material. The results were confirmed by HPLC-electrospray ionization triple quadrupole mass spectrometry (HPLC/MS/MS). The mycotoxins ochratoxin A (OTA) and fumonisins of the B- and C-series (FB 1 , FB 2 , FB 3 , FB 4 , FC 2/3 , and FC 4 ) as well as partially hydrolyzed fumonisins (pHFB 1 , pHFB 2 , pHFB 3 , pHFC 1 , and pHFC 2/3 ) could successfully be detected by MALDI-IMS in mold-infested foodstuffs. The toxins are distributed differently in the material: OTA is co-localized with visible fungal spoilage while fumonisins could be detected throughout the whole sample. This work shows the applicability of MALDI-Imaging Mass Spectrometry (MALDI-MSI) to mycotoxin analysis. It has been demonstrated that the analyzed mycotoxins are differently distributed within moldy foodstuffs. These findings show the potential of MALDI-MSI for the localization of these hazardous compounds in various plant tissues. This article is protected by copyright. All rights reserved.

Protein adsorption/desorption and antibody binding stoichiometry on silicon interferometric biosensors examined with TOF-SIMS

NASA Astrophysics Data System (ADS)

Gajos, Katarzyna; Budkowski, Andrzej; Petrou, Panagiota; Pagkali, Varvara; Awsiuk, Kamil; Rysz, Jakub; Bernasik, Andrzej; Misiakos, Konstantinos; Raptis, Ioannis; Kakabakos, Sotirios

2018-06-01

Time-of-flight secondary ion mass spectrometry has been employed to examine, with biomolecular discrimination, sensing arm areas (20 μm × 600 μm) of integrated onto silicon chips Mach-Zehnder interferometers aiming to optimize their biofunctionalization with regard to indirect immunochemical (competitive) detection of ochratoxin A. Sensing areas are examined after: modification with (3-aminopropyl)triethoxysilane, spotting of OTA-ovalbumin conjugate (probe) from solutions with different concentration, blocking with bovine serum albumin, reaction with OTA-specific mouse monoclonal antibody followed by goat anti-mouse IgG secondary antibody. Component mass loadings of all proteins involved in immunodetection are determined from TOF-SIMS micro-analysis combined with ellipsometry of planar surfaces. These data show that partial desorption of surface-bound probe and blocking protein takes place upon primary immunoreaction to a degree that depends on probe concentration in spotting solution. Taking into account this desorption, apparent binding stoichiometry of both antibodies in immune complexes formed onto chip surface is determined more accurately than the respective evaluation based on real-time sensor response. In addition, mass loadings for probe and secondary antibody is observed to saturate for optimum probe concentrations. Also, principal component analysis of TOF-SIMS data could resolve both immunoreactions and biofunctionalization and discriminate surfaces prepared with optimum probe concentrations from those prepared using suboptimum ones.

Modeling Growth and Toxin Production of Toxigenic Fungi Signaled in Cheese under Different Temperature and Water Activity Regimes

PubMed Central

Camardo Leggieri, Marco; Decontardi, Simone; Bertuzzi, Terenzio; Pietri, Amedeo; Battilani, Paola

2016-01-01

The aim of this study was to investigate in vitro and model the effect of temperature (T) and water activity (aw) conditions on growth and toxin production by some toxigenic fungi signaled in cheese. Aspergillus versicolor, Penicillium camemberti, P. citrinum, P. crustosum, P. nalgiovense, P. nordicum, P. roqueforti, P. verrucosum were considered they were grown under different T (0–40 °C) and aw (0.78–0.99) regimes. The highest relative growth occurred around 25 °C; all the fungi were very susceptible to aw and 0.99 was optimal for almost all species (except for A. versicolor, awopt = 0.96). The highest toxin production occurred between 15 and 25 °C and 0.96–0.99 aw. Therefore, during grana cheese ripening, managed between 15 and 22 °C, ochratoxin A (OTA), penitrem A (PA), roquefortine-C (ROQ-C) and mycophenolic acid (MPA) are apparently at the highest production risk. Bete and logistic function described fungal growth under different T and aw regimes well, respectively. Bete function described also STC, PA, ROQ-C and OTA production as well as function of T. These models would be very useful as starting point to develop a mechanistic model to predict fungal growth and toxin production during cheese ripening and to help advising the most proper setting of environmental factors to minimize the contamination risk. PMID:28029129

Detection of mycotoxins in patients with chronic fatigue syndrome.

PubMed

Brewer, Joseph H; Thrasher, Jack D; Straus, David C; Madison, Roberta A; Hooper, Dennis

2013-04-11

Over the past 20 years, exposure to mycotoxin producing mold has been recognized as a significant health risk. Scientific literature has demonstrated mycotoxins as possible causes of human disease in water-damaged buildings (WDB). This study was conducted to determine if selected mycotoxins could be identified in human urine from patients suffering from chronic fatigue syndrome (CFS). Patients (n = 112) with a prior diagnosis of CFS were evaluated for mold exposure and the presence of mycotoxins in their urine. Urine was tested for aflatoxins (AT), ochratoxin A (OTA) and macrocyclic trichothecenes (MT) using Enzyme Linked Immunosorbent Assays (ELISA). Urine specimens from 104 of 112 patients (93%) were positive for at least one mycotoxin (one in the equivocal range). Almost 30% of the cases had more than one mycotoxin present. OTA was the most prevalent mycotoxin detected (83%) with MT as the next most common (44%). Exposure histories indicated current and/or past exposure to WDB in over 90% of cases. Environmental testing was performed in the WDB from a subset of these patients. This testing revealed the presence of potentially mycotoxin producing mold species and mycotoxins in the environment of the WDB. Prior testing in a healthy control population with no history of exposure to a WDB or moldy environment (n = 55) by the same laboratory, utilizing the same methods, revealed no positive cases at the limits of detection.

Detection of Mycotoxins in Patients with Chronic Fatigue Syndrome

PubMed Central

Brewer, Joseph H.; Thrasher, Jack D.; Straus, David C.; Madison, Roberta A.; Hooper, Dennis

2013-01-01

Over the past 20 years, exposure to mycotoxin producing mold has been recognized as a significant health risk. Scientific literature has demonstrated mycotoxins as possible causes of human disease in water-damaged buildings (WDB). This study was conducted to determine if selected mycotoxins could be identified in human urine from patients suffering from chronic fatigue syndrome (CFS). Patients (n = 112) with a prior diagnosis of CFS were evaluated for mold exposure and the presence of mycotoxins in their urine. Urine was tested for aflatoxins (AT), ochratoxin A (OTA) and macrocyclic trichothecenes (MT) using Enzyme Linked Immunosorbent Assays (ELISA). Urine specimens from 104 of 112 patients (93%) were positive for at least one mycotoxin (one in the equivocal range). Almost 30% of the cases had more than one mycotoxin present. OTA was the most prevalent mycotoxin detected (83%) with MT as the next most common (44%). Exposure histories indicated current and/or past exposure to WDB in over 90% of cases. Environmental testing was performed in the WDB from a subset of these patients. This testing revealed the presence of potentially mycotoxin producing mold species and mycotoxins in the environment of the WDB. Prior testing in a healthy control population with no history of exposure to a WDB or moldy environment (n = 55) by the same laboratory, utilizing the same methods, revealed no positive cases at the limits of detection. PMID:23580077

A comparative analysis of mycotoxin contamination of supermarket and premium brand pelleted dog food in Durban, South Africa.

PubMed

Singh, Sanil D; Chuturgoon, Anil A

2017-10-06

Dry pelleted dog food in the South African market is available via supermarkets, pet stores (standard brands [SBs]) and veterinary channels (premium brands [PBs]). For the purpose of this study, the supermarket channel included the cheaper quality foods and PBs were sold via the veterinary channel (n = 20). These feeds were analysed for four main mycotoxins (aflatoxins [AF], fumonisin [FB], ochratoxin A [OTA] and zearalenone [ZEA]) using standard welldescribed extraction, characterisation and quantitation processes. Irrespective of the brand or marketing channel, all foods were contaminated with fungi (mainly Aspergillus flavus, Aspergillus fumigatus and Aspergillus parasiticus) and mycotoxins (most prevalent being aflatoxins and fumonisins). This was observed in all 20 samples irrespective of the marketing channel or perceived quality. Also, many samples within each marketing channel failed the 10 ppb limit for aflatoxin set by regulations in South Africa. Although fumonisin was detected in all samples, a single sample failed the Food and Drug Administration (FDA) limit of 100 ppb. Both OTA and ZEA were found at low concentrations and were absent in some samples. This study suggested that higher priced dog food does not ensure superior quality or that it is free from contamination with fungi or mycotoxins. However, analysis of the more expensive PBs did reveal contamination concentrations lower than those of the SBs.

Las Cumbres Observatory 1-Meter Global Science Telescope Network

NASA Astrophysics Data System (ADS)

Pickles, Andrew; Dubberley, M.; Haldeman, B.; Haynes, R.; Posner, V.; Rosing, W.; staff, LCOGT

2009-05-01

We present the optical, mechanical and electronic design of the LCOGT 1-m telescope. These telescopes are planned to go in pairs to each of 6 sites worldwide, complementing 0.4m telescopes and 2-m telescopes at two existing sites. This science network is designed to provide continuously available photometric monitoring and spectroscopy of variable sources. The 1-m optical design is an f/8 quasi-RC system, with a doublet corrector and field flattener to provide good image quality out to 0.8 degrees. The field of view of the Fairchild 4K science CCD is 27 arcmin, with 0.39 arcsec pixels. The mechanical design includes a stiff C-ring equatorial mount and friction drive rollers, mounted on a triangular base that can be adjusted for latitude. Another friction drive is coupled at the Declination axis to the M1 mirror cell, that forms the main Optical Tube Assembly (OTA) structural element. The OTA design includes a stiff carbon fiber truss assembly, with offset vanes to an M2 drive that provides remote focus, tilt and collimation. The tube assembly weighs about 600 Kg, including Hextek mirrors, 4K science CCD, filter wheel, autoguiders and medium resolution spectrograph pick-off fiber. The telescopes will be housed in domes at existing observatory sites. They are designed to operate remotely and reliably under centralized control for automatic, optimized scheduling of observations with available hardware.

A tip/tilt mirror with large dynamic range for the ESO VLT Four Laser Guide Star Facility

NASA Astrophysics Data System (ADS)

Rijnveld, N.; Henselmans, R.; Nijland, B.

2011-09-01

One of the critical elements in the Four Laser Guide Star Facility (4LGSF) for the ESO Very Large Telescope (VLT) is the Optical Tube Assembly (OTA), consisting of a stable 20x laser beam expander and an active tip/tilt mirror, the Field Selector Mechanism (FSM). This paper describes the design and performance testing of the FSM. The driving requirement for the FSM is its large stroke of +/-6.1 mrad, in combination with less than 1.5 μrad RMS absolute accuracy. The FSM design consists of a Zerodur mirror, bonded to a membrane spring and strut combination to allow only tip and tilt. Two spindle drives actuate the mirror, using a stiffness based transmission to increase resolution. Absolute accuracy is achieved with two differential inductive sensor pairs. A prototype of the FSM is realized to optimize the control configuration and measure its performance. Friction in the spindle drive is overcome by creating a local velocity control loop between the spindle drives and the shaft encoders. Accuracy is achieved by using a cascaded low bandwidth control loop with feedback from the inductive sensors. The pointing jitter and settling time of the FSM are measured with an autocollimator. The system performance meets the strict requirements, and is ready to be implemented in the first OTA.

Introduction of the non-technical skills for surgeons (NOTSS) system in a Japanese cancer center.

PubMed

Tsuburaya, Akira; Soma, Takahiro; Yoshikawa, Takaki; Cho, Haruhiko; Miki, Tamotsu; Uramatsu, Masashi; Fujisawa, Yoshikazu; Youngson, George; Yule, Steven

2016-12-01

Non-technical skills rating systems, which are designed to support surgical performance, have been introduced worldwide, but not officially in Japan. We performed a pilot study to evaluate the "non-technical skills for surgeons" (NOTSS) rating system in a major Japanese cancer center. Upper gastrointestinal surgeons were selected as trainers or trainees. The trainers attended a master-class on NOTSS, which included simulated demo-videos, to promote consistency across the assessments. The trainers thereafter commenced observing the trainees and whole teams, utilizing the NOTSS and "observational teamwork assessment for surgery" (OTAS) rating systems, before and after their education. Four trainers and six trainees were involved in this study. Test scores for understanding human factors and the NOTSS system were 5.89 ± 1.69 and 8.00 ± 1.32 before and after the e-learning, respectively (mean ± SD, p = 0.010). The OTAS scores for the whole team improved significantly after the trainees' education in five out of nine stages (p < 0.05). There were no differences in the NOTSS scores before and after education, with a small improvement in the total scores for the "teamwork and communication" and "leadership" categories. These findings demonstrate that implementing the NOTSS system is feasible in Japan. Education of both surgical trainers and trainees would contribute to better team performance.

[Filamentous fungi and mycotoxins as potential occupational risk factors among farmers harvesting various crops].

PubMed

Krysińska-Traczyk, Ewa; Perkowski, Juliusz; Kostecki, Marian; Dutkiewicz, Jacek; Kiecana, Irena

2003-01-01

The studies to determine the level of filamentous fungi and mycotoxins were carried out in samples of grain and grain dust during threshing of cereals by a combine harvester. High concentration of fungi was noted in grain and grain dust samples, it ranged from 5.0 to 520.0 cfu/g.10(3) and from 275.0 to 2825.0 cfu/g.10(3), respectively Allergizing and toxigenic fungi of Alternaria, Geotrichum, Cladosporium, Penicillium, Aspergillus and Fusarium species were observed in the study samples of grain and grain dust. In the samples of wheat grain, mycotoxins were also noted: moniliformin (MON), deoxynivalenol (DON) and ochratoxin A (OTA); their concentrations ranged from 0.025 to 0.088 microgram/g; 0.015-0.068 microgram/g; and from 0.0004 to 0.0008 microgram/g, respectively. The level of mycotoxins in the grain dust samples was within the range of 0.025-0.149 microgram/g-MON; 0.015-0.215 microgram/g-DON; 0.015-0.360 microgram/g-NIV; and 0.0004-0.0012 microgram/g-OTA. A significant correlation was observed between the occurrence of fungi of Fusarium species and the concentration of pathologic mycotoxins. The results confirm a considerable occupational risk among farmers engaged in grain threshing due to inhalation of pathogenic species of filamentous fungi and mycotoxins.

Oxytocin signaling in basolateral and central amygdala nuclei differentially regulates the acquisition, expression, and extinction of context-conditioned fear in rats

PubMed Central

Campbell-Smith, Emma J.; Holmes, Nathan M.; Lingawi, Nura W.; Panayi, Marios C.

2015-01-01

The present study investigated how oxytocin (OT) signaling in the central (CeA) and basolateral (BLA) amygdala affects acquisition, expression, and extinction of context-conditioned fear (freezing) in rats. In the first set of experiments, acquisition of fear to a shocked context was impaired by a preconditioning infusion of synthetic OT into the CeA (Experiment 1) or BLA (Experiment 2). In the second set of experiments, expression of context fear was enhanced by a pre- or post-extinction CeA infusion of synthetic OT (Experiments 3–6) or a selective OT receptor agonist, TGOT (Experiment 4). This enhancement of fear was blocked by coadministration of an OT receptor antagonist, OTA (Experiment 5) and context fear was suppressed by administration of the antagonist alone (Experiment 6). In the third set of experiments, expression of context fear was suppressed, not enhanced, by a preextinction BLA infusion of synthetic OT or a selective OT receptor agonist, TGOT (Experiments 7 and 8). This suppression of fear was blocked by coadministration of the OT receptor antagonist, OTA (Experiment 8). Taken together, these findings show that the involvement of the CeA and BLA in expression and extinction of context-conditioned fear is dissociable, and imply a critical role for oxytocin signaling in amygdala-based regulation of aversive learning. PMID:25878137

Adsorption of aflatoxin B1, zearalenone and ochratoxin A by microorganisms isolated from Kefir grains.

PubMed

Taheur, Fadia Ben; Fedhila, Kais; Chaieb, Kamel; Kouidhi, Bochra; Bakhrouf, Amina; Abrunhosa, Luís

2017-06-19

A strategy to reduce the deleterious effects of mycotoxins is to use dietary supplements that contain microorganisms that bind mycotoxins and decrease their gastrointestinal absorption. Novel strains were isolated from a Kefir culture and assessed for their mycotoxin adsorption and biotransformation ability. The most active strains were identified using DNA sequencing, and the stability of microorganism/mycotoxin complexes was evaluated using buffer solutions to simulate the pH conditions in the gastrointestinal tract. Our results showed that the microorganism consortium of Kefir grains adsorbed 82 to 100% of aflatoxin B1 (AFB1), zearalenone (ZEA) and ochratoxin A (OTA) when cultivated in milk. The main strains that were capable of mycotoxin adsorption were identified as Lactobacillus kefiri, Kazachstania servazzii and Acetobacter syzygii. The strain L. kefiri KFLM3 was the most active, adsorbing 80 to 100% of the studied mycotoxins when cultivated in milk. Nonetheless, the strain K. servazzii KFGY7 retained more mycotoxin after the desorption experiments (65, 69 and 67% for AFB1, OTA and ZEA, respectively). These findings suggest that Kefir consumption may help to reduce gastrointestinal absorption of these mycotoxins and consequently reduce their toxic effects. The isolated strains may be of interest for the development of fermented dairy products for human consumption that have a new probiotic characteristic, the adsorption of mycotoxins. Copyright © 2017 Elsevier B.V. All rights reserved.

[Intramedullary stabilisation of displaced midshaft clavicular fractures: does the fracture pattern (simple vs. complex) influence the anatomic and functional result].

PubMed

Langenhan, R; Reimers, N; Probst, A

2014-12-01

Displaced midshaft clavicular fractures are often treated operatively. The most common way of treatment is plating. Elastic stable intramedullary nailing (ESIN) is an alternative, but seldom used. Studies showed comparable or even better results for intramedullary nailing than for plating in simple 2- or 3-fragment midshaft fractures. The indication of ESIN for multifragmentary clavicular fractures is discussed critically in the literature because of reduced primary stability and danger of secondary shortening. Until now only few studies report functional results after fracture healing depending on the fracture type. To the best of our knowledge there is no study showing significantly worse functional scores for ESIN in complex displaced midshaft fractures. The objective of this study was to examine anatomic and functional results of simple (2 or 3 fragments, OTA type 15B1 and 15B2) and complex (multifragmentary, OTA type 15B3) displaced midshaft clavicula fractures after internal fixation. Between 2009 and 2012, 40 patients (female/male 10/30; mean age 33 [16-60] years) with closed displaced midshaft clavicular fractures were treated by open reduction and ESIN (Titanium Elastic Nail [TEN], Synthes, Umkirch, Germany). Thirty-seven patients were retrospectively analysed after a mean of 27 (12-43) months. Twenty patients (group A) had simple fractures (OTA type 15B1 and 15B2), 17 patients (group B) had complex fractures (OTA type 15B3). All shoulder joints were postoperatively treated functionally for six weeks without weight limited to 90° abduction/flexion. Both groups were comparable in gender, age, body mass index, months until metal removal, number of physiotherapy sessions and time until follow-up examination. Joint function (neutral zero method) and strength (standing patient with arm in 90° abduction, holding 1-12 kg for 5 sec) in both shoulders were documented. The distance between the centre of the jugulum and the lateral acromial border was measured for both sides. The DASH, Constant-Murley, Oxford shoulder and clavicular scores (Jubel) were calculated. Patients documented contentedness of outcome by VAS between 0 (absolute discontented) and 10 (very contented). Complications were recorded. Operatively treated displaced midshaft clavicular fractures. in comparison to the healthy side in group A had an average shortening of 5 (0-20) mm and in group B of 10 (3-25) mm, with a statistical significance between both groups. Patients of both groups were very contented with the results (VAS group A: 9.6; B: 9.5). DASH score (group A: 28; B: 3.1), Constant-Murley score (group A: 95.0; B: 93.8), Oxford shoulder score (group A: 46.2; B: 45.9) and the clavicula score (Jubel) (group A: 1.2; B: 2.1) were comparable between both groups without significance. In 4 patients (11%) complications occurred. Once (group B) an infection was seen, three times (group B) the ESIN had to be shortened on the medial side because of telescoping. Open ESIN of simple and complex displaced midshaft clavicular fractures leads after an average of 27 months to good or even excellent results. Healing of the clavicle in a modestly shortened position does not impair the patient. Georg Thieme Verlag KG Stuttgart · New York.

Dilemmas in Forward Basing: Understanding the Impact of the American Military Presence in Bahrain

DTIC Science & Technology

2014-06-01

bases, local businessmen, a base workers group, and members of the self -defense force.75 Ultimately, Governor, Ota was voted out of office and a...U.S. access to Turkish soil in 1979 to rescue hostages in Tehran during the Islamic Revolution in Iran. Relations did not begin to heal until after...demonstrators from the roundabout with rubber bullets, and teargas. Four demonstrators were killed during the raid and others died shortly after. The

Parity generator and parity checker in the modified trinary number system using savart plate and spatial light modulator

NASA Astrophysics Data System (ADS)

Ghosh, Amal K.

2010-09-01

The parity generators and the checkers are the most important circuits in communication systems. With the development of multi-valued logic (MVL), the proposed system with parity generators and checkers is the most required using the recently developed optoelectronic technology in the modified trinary number (MTN) system. This system also meets up the tremendous needs of speeds by exploiting the savart plates and spatial light modulators (SLM) in the optical tree architecture (OTA).

Laser treatment of medical skin disease in women.

PubMed

LaRosa, C; Chiaravalloti, A; Jinna, S; Berger, W; Finch, J

2017-09-01

Laser treatment is a relatively new and increasingly popular modality for the treatment of many dermatologic conditions. A number of conditions that predominantly occur in women and that have a paucity of effective treatments include rosacea, connective tissue disease, melasma, nevus of Ota, lichen sclerosus (LS), notalgia paresthetica and macular amyloidosis, and syringomas. Laser therapy is an important option for the treatment of patients with these conditions. This article will review the body of literature that exists for the laser treatment of women with these medical conditions.

The use of picosecond lasers beyond tattoos.

PubMed

Forbat, E; Al-Niaimi, F

2016-10-01

Picosecond lasers are a novel laser with the ability to create a pulse of less than one nanosecond. They have been available in the clinical context since 2012. Dermatologists are now using picosecond lasers regularly for the treatment of blue and green pigment tattoo removal. This article reviews the use of picosecond lasers beyond tattoo removal. The overall consensus for the use of picosecond lasers beyond tattoo treatment is positive. With examples of this in the treatment of nevus of Ota, minocycline-induced pigmentation, acne scarring, and rhytides.

Phase equilibria and crystal chemistry of rubidium niobates and rubidium tantalates

NASA Technical Reports Server (NTRS)

Minor, D. B.; Roth, R. S.; Parker, H. S.; Brower, W. S.

1977-01-01

The phase equilibria relations and crystal chemistry of portions of the Rb2O-Nb2O5 and Rb2O-Ta2O5 systems were investigated for structures potentially useful as ionic conductors. A hexagonal tungsten bronze-type (HTB) structure was found in both systems as well as three hexagonal phases with mixed HTB-pyrochlore type structures. Ion exchange experiments between various alkali ions are described for several phases. Unit cell dimensions and X-ray diffraction powder patterns are reported.

Mapping our genes: The genome projects: How big, how fast

DOE Office of Scientific and Technical Information (OSTI.GOV)

none,

For the past 2 years, scientific and technical journals in biology and medicine have extensively covered a debate about whether and how to determine the function and order of human genes on human chromosomes and when to determine the sequence of molecular building blocks that comprise DNA in those chromosomes. In 1987, these issues rose to become part of the public agenda. The debate involves science, technology, and politics. Congress is responsible for /open quotes/writing the rules/close quotes/ of what various federal agencies do and for funding their work. This report surveys the points made so far in the debate,more » focusing on those that most directly influence the policy options facing the US Congress. Congressional interest focused on how to assess the rationales for conducting human genome projects, how to fund human genome projects (at what level and through which mechanisms), how to coordinate the scientific and technical programs of the several federal agencies and private interests already supporting various genome projects, and how to strike a balance regarding the impact of genome projects on international scientific cooperation and international economic competition in biotechnology. OTA prepared this report with the assistance of several hundred experts throughout the world. 342 refs., 26 figs., 11 tabs.« less

Biomass and nutrient concentration of sweet corn roots and shoots under organic amendments application.

PubMed

Ahmad, Amjad A; Fares, Ali; Paramasivam, Sivapatham; Elrashidi, Moustafa A; Savabi, Reza M

2009-09-01

Two field experiments were conducted at the Waimanalo research station on the island of O'ahu, Hawaii to study the effect of chicken (CM) and dairy (DM) manures on biomass and nutrient concentration in sweet corn roots and shoots. Sweet corn (super sweet 10, Zea Mays L. subsp. mays) was grown for two consecutive growing seasons under four rates of application (0, 168, 337, and 672 kg ha(-1) total N equivalent) and one time (OTA) or two time (TTA) applications of organic manure types and rates. There were significant effects of types, rates, and number of manure applications on dry biomass and macro- and micro-nutrient concentration in roots and shoots tissues. Results of root tissue indicated a significant accumulation of N and C under CM and DM treatments compared with the control treatment. Manure application rates significantly increased the accumulation of N and C in root tissue. Dry weight of roots and shoots and both macro- and micro-nutrient contents in the plant tissues significantly increased under TTA treatment compared with OTA treatment. There was a significant correlation (r(2) = 0.46 to 0.81) between root biomass, macro-, and micro-nutrient contents during both growing seasons. The results of the study indicates that amending soils with CM at the highest application rate provided the best crop performance in terms of root and shoot biomass, crop N, C, and other macro- and micro-nutrients.

Prevalence of musculoskeletal disorders among orthopedic trauma surgeons: an OTA survey

PubMed Central

AlQahtani, Saad M.; Alzahrani, Mohammad M.; Harvey, Edward J.

2016-01-01

Background Occupational injuries and hazards have gained increased attention in the surgical community in general and in the orthopedic literature specifically. The aim of this study was to assess prevalence and characteristics of musculoskeletal disorders among orthopedic trauma surgeons and the impact of these injuries on the surgeons’ practices. Methods We sent a modified version of the physical discomfort survey to surgeon members of the Orthopaedic Trauma Association (OTA) via email. Data were collected and descriptive statistics were analyzed. Results A total of 86 surgeons completed the survey during the period of data collection; 84.9% were men, more than half were 45 years or older and 40.6% were in practice for 10 years or more. More than 66% of respondents reported a musculoskeletal disorder that was related to work; the most common was low back pain (29.3%). The number of body regions involved and disorders diagnosed was associated with increasing age and number of years in practice (p = 0.033). Time off work owing to these disorders was associated with working in a private setting (p = 0.045) and working in more than 1 institute (p = 0.009). Conclusion To our knowledge, our study is the first to report a high percentage of orthopedic trauma surgeons sustaining occupational injuries some time in their careers. The high cost of management and rehabilitation of these injuries in addition to the related number of missed work days indicate the need for increased awareness and implementation of preventive measures. PMID:26812408

Effect of wavelength on cutaneous pigment using pulsed irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sherwood, K.A.; Murray, S.; Kurban, A.K.

Several reports have been published over the last two decades describing the successful removal of benign cutaneous pigmented lesions such as lentigines, cafe au lait macules' nevi, nevus of Ota, and lentigo maligna by a variety of lasers such as the excimer (351 nm), argon (488,514 nm), ruby (694 nm), Nd:YAG (1060 nm), and CO/sub 2/ (10,600 nm). Laser treatment has been applied to lesions with a range of pigment depths from superficial lentigines in the epidermis to the nevus of Ota in the reticular dermis. Widely divergent laser parameters of wavelength, pulse duration, energy density, and spotsizes have beenmore » used, but the laser parameters used to treat this range of lesions have been arbitrary, with little effort focused on defining optimal laser parameters for removal of each type. In this study, miniature black pig skin was exposed to five wavelengths (504, 590, 694, 720, and 750 nm) covering the absorption spectrum of melanin. At each wavelength, a range of energy densities was examined. Skin biopsies taken from laser-exposed sites were examined histologically in an attempt to establish whether optimal laser parameters exist for destroying pigment cells in skin. Of the five wavelengths examined, 504 nm produced the most pigment specific injury; this specificity being maintained even at the highest energy density of 7.0 J/cm2. Thus, for the destruction of melanin-containing cells in the epidermal compartment, 504 nm wavelength appears optimal.« less

Biodiversity and ITS-RFLP Characterisation of Aspergillus Section Nigri Isolates in Grapes from Four Traditional Grape-Producing Areas in Greece

PubMed Central

Kizis, Dimosthenis; Natskoulis, Pantelis; Nychas, George-John E.; Panagou, Efstathios Z.

2014-01-01

A study on the occurrence of Aspergillus section Nigri species on grapes from four traditional grape-producing areas in Greece during the 2011/2012 vintage, and their capability to produce OTA was conducted. One hundred and twenty-eight black aspergilli isolates were characterised at the species level initially by the use of morphological criteria in accordance with appropriate keys, followed by molecular characterisation performed with Polymerase Chain Reaction–Restriction Fragment Length Polymorphism (PCR-RFLP) of the 5.8 ribosomal RNA gene Internal Transcribed Spacer region (5.8 rRNA ITS). Restriction enzyme digestion of the ITS amplicons using the HhaI, HinfI and RsaI, endonucleases distinguished eleven different patterns of restriction fragment length polymorphism (RFLP), four for each of the HhaI and RsaI digests and three for HinfI. From a total number of 128 individual isolates, 124 were classified into four Aspergillus species corresponding to A. carbonarius, A. tubingensis, A. japonicus and A. ibericus, and the remaining 4 were classified as members of the A. niger aggregate. A. carbonarius and A. tubingensis being the main representative species were equally counted, with higher geographical representation of the former in southern and the latter in northern regions, respectively. All isolates were tested for their ochratoxigenic potential by use of High Performance Liquid Chromatography (HPLC) and Enzyme Linked Immuno Sorbent Assay (ELISA), resulting in significant interspecies differences in OTA production. PMID:24710283

A Method for Multiple Mycotoxin Analysis in Wines by Solid Phase Extraction and Multifunctional Cartridge Purification, and Ultra-High-Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry

PubMed Central

Tamura, Masayoshi; Takahashi, Ayumi; Uyama, Atsuo; Mochizuki, Naoki

2012-01-01

An analytical method using two solid phase extractions and ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed for the identification and quantification of 14 mycotoxins (patulin, deoxynivalenol, aflatoxins B1, B2, G1, G2, M1, T-2 toxin, HT-2 toxin, zearalenone, fumonisins B1, B2, B3, and ochratoxin A) in domestic and imported wines. Mycotoxins were purified with an Oasis HLB cartridge, followed by a MultiSepTM #229 Ochra. As a result, sufficient removal of the pigments and highly polar matrices from the red wines was achieved. UHPLC conditions were optimized, and 14 mycotoxins were separated in a total of 13 min. Determinations performed using this method produced high correlation coefficients for the 14 mycotoxins (R > 0.990) and recovery rates ranging from 76 to 105% with good repeatability (relative standard deviation RSD < 12%). Twenty-seven samples of domestic and imported wines were analyzed using this method. Although ochratoxin A (OTA) and fumonisins (FMs) were detected in several samples, the FM levels were less than limits of quantification (LOQs) (1 μg/L), and even the largest of the OTA levels was below the EU regulatory level (2 μg/L). These results suggest that the health risk posed to consumers from the wines available in Japan is relatively low. PMID:22822458

Shock treatment: using immersive digital realism to restage and re-examine milgram's 'obedience to authority' research.

PubMed

Haslam, S Alexander; Reicher, Stephen D; Millard, Kathryn

2015-01-01

Attempts to revisit Milgram's 'Obedience to Authority' (OtA) paradigm present serious ethical challenges. In recent years new paradigms have been developed to circumvent these challenges but none involve using Milgram's own procedures and asking naïve participants to deliver the maximum level of shock. This was achieved in the present research by using Immersive Digital Realism (IDR) to revisit the OtA paradigm. IDR is a dramatic method that involves a director collaborating with professional actors to develop characters, the strategic withholding of contextual information, and immersion in a real-world environment. 14 actors took part in an IDR study in which they were assigned to conditions that restaged Milgrams's New Baseline ('Coronary') condition and four other variants. Post-experimental interviews also assessed participants' identification with Experimenter and Learner. Participants' behaviour closely resembled that observed in Milgram's original research. In particular, this was evidenced by (a) all being willing to administer shocks greater than 150 volts, (b) near-universal refusal to continue after being told by the Experimenter that "you have no other choice, you must continue" (Milgram's fourth prod and the one most resembling an order), and (c) a strong correlation between the maximum level of shock that participants administered and the mean maximum shock delivered in the corresponding variant in Milgram's own research. Consistent with an engaged follower account, relative identification with the Experimenter (vs. the Learner) was also a good predictor of the maximum shock that participants administered.

Scapula fractures: interobserver reliability of classification and treatment.

PubMed

Neuhaus, Valentin; Bot, Arjan G J; Guitton, Thierry G; Ring, David C; Abdel-Ghany, Mahmoud I; Abrams, Jeffrey; Abzug, Joshua M; Adolfsson, Lars E; Balfour, George W; Bamberger, H Brent; Barquet, Antonio; Baskies, Michael; Batson, W Arnold; Baxamusa, Taizoon; Bayne, Grant J; Begue, Thierry; Behrman, Michael; Beingessner, Daphne; Biert, Jan; Bishop, Julius; Alves, Mateus Borges Oliveira; Boyer, Martin; Brilej, Drago; Brink, Peter R G; Brunton, Lance M; Buckley, Richard; Cagnone, Juan Carlos; Calfee, Ryan P; Campinhos, Luiz Augusto B; Cassidy, Charles; Catalano, Louis; Chivers, Karel; Choudhari, Pradeep; Cimerman, Matej; Conflitti, Joseph M; Costanzo, Ralph M; Crist, Brett D; Cross, Brian J; Dantuluri, Phani; Darowish, Michael; de Bedout, Ramon; DeCoster, Thomas; Dennison, David G; DeNoble, Peter H; DeSilva, Gregory; Dienstknecht, Thomas; Duncan, Scott F; Duralde, Xavier A; Durchholz, Holger; Egol, Kenneth; Ekholm, Carl; Elias, Nelson; Erickson, John M; Esparza, J Daniel Espinosa; Fernandes, C H; Fischer, Thomas J; Fischmeister, Martin; Forigua Jaime, E; Getz, Charles L; Gilbert, Richard S; Giordano, Vincenzo; Glaser, David L; Gosens, Taco; Grafe, Michael W; Filho, Jose Eduardo Grandi Ribeiro; Gray, Robert R L; Gulotta, Lawrence V; Gummerson, Nigel William; Hammerberg, Eric Mark; Harvey, Edward; Haverlag, R; Henry, Patrick D G; Hobby, Jonathan L; Hofmeister, Eric P; Hughes, Thomas; Itamura, John; Jebson, Peter; Jenkinson, Richard; Jeray, Kyle; Jones, Christopher M; Jones, Jedediah; Jubel, Axel; Kaar, Scott G; Kabir, K; Kaplan, F Thomas D; Kennedy, Stephen A; Kessler, Michael W; Kimball, Hervey L; Kloen, Peter; Klostermann, Cyrus; Kohut, Georges; Kraan, G A; Kristan, Anze; Loebenberg, Mark I; Malone, Kevin J; Marsh, L; Martineau, Paul A; McAuliffe, John; McGraw, Iain; Mehta, Samir; Merchant, Milind; Metzger, Charles; Meylaerts, S A; Miller, Anna N; Wolf, Jennifer Moriatis; Murachovsky, Joel; Murthi, Anand; Nancollas, Michael; Nolan, Betsy M; Omara, Timothy; Omid, Reza; Ortiz, Jose A; Overbeck, Joachim P; Castillo, Alberto Pérez; Pesantez, Rodrigo; Polatsch, Daniel; Porcellini, G; Prayson, Michael; Quell, M; Ragsdell, Matthew M; Reid, James G; Reuver, J M; Richard, Marc J; Richardson, Martin; Rizzo, Marco; Rowinski, Sergio; Rubio, Jorge; Guerrero, Carlos G Sánchez; Satora, Wojciech; Schandelmaier, Peter; Scheer, Johan H; Schmidt, Andrew; Schubkegel, Todd A; Schulte, Leah M; Schumer, Evan D; Sears, Benjamin W; Shafritz, Adam B; Shortt, Nicholas L; Siff, Todd; Silva, Dario Mejia; Smith, Raymond Malcolm; Spruijt, Sander; Stein, Jason A; Pemovska, Emilija Stojkovska; Streubel, Philipp N; Swigart, Carrie; Swiontkowski, Marc; Thomas, George; Tolo, Eric T; Turina, Matthias; Tyllianakis, Minos; van den Bekerom, Michel P J; van der Heide, Huub; van de Sande, M A J; van Eerten, P V; Verbeek, Diederik O F; Hoffmann, David Victoria; Vochteloo, A J H; Wagenmakers, Robert; Wall, Christopher J; Wallensten, Richard; Wascher, Daniel C; Weiss, Lawrence; Wiater, J Michael; Wills, Brian P D; Wint, Jeffrey; Wright, Thomas; Young, Jason P; Zalavras, Charalampos; Zura, Robert D; Zyto, Karol

2014-03-01

There is substantial variation in the classification and management of scapula fractures. The first purpose of this study was to analyze the interobserver reliability of the OTA/AO classification and the New International Classification for Scapula Fractures. The second purpose was to assess the proportion of agreement among orthopaedic surgeons on operative or nonoperative treatment. Web-based reliability study. Independent orthopaedic surgeons from several countries were invited to classify scapular fractures in an online survey. One hundred three orthopaedic surgeons evaluated 35 movies of three-dimensional computerized tomography reconstruction of selected scapular fractures, representing a full spectrum of fracture patterns. Fleiss kappa (κ) was used to assess the reliability of agreement between the surgeons. The overall agreement on the OTA/AO classification was moderate for the types (A, B, and C, κ = 0.54) with a 71% proportion of rater agreement (PA) and for the 9 groups (A1 to C3, κ = 0.47) with a 57% PA. For the New International Classification, the agreement about the intraarticular extension of the fracture (Fossa (F), κ = 0.79) was substantial and the agreement about a fractured body (Body (B), κ = 0.57) or process was moderate (Process (P), κ = 0.53); however, PAs were more than 81%. The agreement on the treatment recommendation was moderate (κ = 0.57) with a 73% PA. The New International Classification was more reliable. Body and process fractures generated more disagreement than intraarticular fractures and need further clear definitions.

Surgical treatment of distal tibia fractures: open versus MIPO.

PubMed

Gülabi, Deniz; Bekler, Halil İbrahim; Sağlam, Fevzi; Taşdemir, Zeki; Çeçen, Gültekin Sıtkı; Elmalı, Nurzat

2016-01-01

Treatment of the distal tibial fractures are challenging due to the limited soft tissue, subcutaneous location and poor vascularity. In this control-matched study, it was aimed to compare the traditional open reduction and internal fixation with minimal invasive plating (MIPO). We hypothesized that superior results may be achieved with MIPO technique. 22 patients treated with traditional open reduction and internal fixation were matched with 22 patients treated with closed reduction and MIPO on the basis of age (±3), gender, and fracture pattern (AO classification). Evaluation was assed according to the wound problems, the American Orthopaedic Foot and Ankle surgery (AOFAS) scoring, radiological union, malunion, delayed union, hospitalisation time, time from injury to surgery, and operation time. There was no significant difference in the distribution of AO/OTA classification, age, gender, AOFAS score, time from injury to operation, follow-up, bone union time, delayed union, malunion and infection (p>0.05). The operation time was significantly longer in the open group than in the MIPO group: 69.59±7.21 min. for the ORIF, and 61.14±5.61 for the MIPO group (p<0.01).The hospitalisation time was significantly longer in the open group than in the MIPO group: 7.64±4.71 days for the MIPO, and 10.18±4.32 days for the ORIF group (p<0.05). MIPO technique can be beneficial for the treatment of distal tibia AO/OTA A and B type fractures with reduced hospital stay, cost-effectiveness, and infection rate.

Metal Oxide Supported Vanadium Substituted Keggin Type Polyoxometalates as Catalyst For Oxidation of Dibenzothiophene

NASA Astrophysics Data System (ADS)

Lesbani, Aldes; Novri Meilyana, Sarah; Karim, Nofi; Hidayati, Nurlisa; Said, Muhammad; Mohadi, Risfidian; Miksusanti

2018-01-01

Supported polyoxometalatate H4[γ-H2SiV2W10O40]·nH2O with metal oxide i.e. silica, titanium, and tantalum was successfully synthesized via wet impregnation method to form H4[γ-H2SiV2W10O40]·nH2O-Si, H4[γ-H2SiV2W10O40]·nH2O-Ti, and H4[γ-H2SiV2W10O40]·nH2O-Ta. Characterization was performed using FTIR spectroscopy, X-Ray analyses, and morphology analyses using SEM. All compounds were used as the catalyst for desulfurization of dibenzothiophene (DBT). Silica and titanium supported polyoxometalate H4[γ-H2SiV2W10O40]·nH2O better than tantalum due to retaining crystallinity after impregnation process. On the other hand, compound H H4[γ-H2SiV2W10O40]·nH2O-Ta showed high catalytic activity than other supported metal oxides for desulfurization of DBT. Optimization desulfurization process resulted in 99% conversion of DBT under a mild condition at 70 °C, 0.1 g catalyst, and reaction for 3 hours. Regeneration studies showed catalyst H4[γ-H2SiV2W10O40]·nH2O-Ti was remaining catalytic activity for desulfurization of DBT.

Testbed Demonstration of Low Order Wavefront Sensing and Control Technology for WFIRST Coronagraph

NASA Astrophysics Data System (ADS)

Shi, Fang; Balasubramanian, K.; Cady, E.; Kern, B.; Lam, R.; Mandic, M.; Patterson, K.; Poberezhskiy, I.; Shields, J.; Seo, J.; Tang, H.; Truong, T.; Wilson, D.

2017-01-01

NASA’s WFIRST-AFTA Coronagraph will be capable of directly imaging and spectrally characterizing giant exoplanets similar to Neptune and Jupiter, and possibly even super-Earths, around nearby stars. To maintain the required coronagraph performance in a realistic space environment, a Low Order Wavefront Sensing and Control (LOWFS/C) subsystem is necessary. The LOWFS/C will use the rejected stellar light to sense and suppress the telescope pointing drift and jitter as well as low order wavefront errors due to the changes in thermal loading of the telescope and the rest of the observatory. The LOWFS/C uses a Zernike phase contrast wavefront sensor with the phase shifting disk combined with the stellar light rejecting occulting mask, a key concept to minimize the non-common path error. Developed as a part of the Dynamic High Contrast Imaging Testbed (DHCIT), the LOWFS/C subsystem also consists of an Optical Telescope Assembly Simulator (OTA-S) to generate the realistic line-of-sight (LoS) drift and jitter as well as low order wavefront error from WFIRST-AFTA telescope’s vibration and thermal drift. The entire LOWFS/C subsystem have been integrated, calibrated, and tested in the Dynamic High Contrast Imaging Testbed. In this presentation we will show the results of LOWFS/C performance during the dynamic coronagraph tests in which we have demonstrated that LOWFS/C is able to maintain the coronagraph contrast with the presence of WFIRST like line-of-sight drift and jitter as well as low order wavefront drifts.

Occurrence of mycotoxin producing fungi in bee pollen.

PubMed

González, G; Hinojo, M J; Mateo, R; Medina, A; Jiménez, M

2005-11-15

The natural mycobiota occurring in bee pollen is studied in the present report with special attention to analyze the incidence of fungal species that are potential producers of mycotoxins. A total of 90 ready-to-eat bee pollen samples were analyzed. Eighty-seven samples were collected in stores placed in different Spanish areas and three were from Buenos Aires (Argentina). The statistical results (ANOVA) showed that yeasts and Penicillium spp. were the predominant fungi. With regard to the potential mycotoxin producing species, Penicillium verrucosum, Aspergillus niger aggregate, Aspergillus carbonarius, Aspergillus ochraceus, Aspergillus flavus, Aspergillus parasiticus and Alternaria spp. were found. The last genus was isolated very frequently. The potential ability for producing ochratoxin A (OTA) and aflatoxins B(1), B(2), G(1) and G(2) was studied by culturing in vitro the isolates followed by analysis of these mycotoxins in culture extracts by HPLC with fluorescent detection. It was found that 100%, 53.3%, 33.3% and 25% of the isolates of A. carbonarius, A. ochraceus, P. verrucosum and A. niger aggregate, respectively, produced OTA. Moreover, 28.6% of the isolates from the A. flavus plus A. parasiticus group were able to produce aflatoxin B(1). Aflatoxin B(2) was detected in only 10% of the cultures. Aflatoxins G(1) and G(2) were not detected in cultures under the assayed conditions. This is the first report carried out on the natural mycobiota occurring in bee pollen in general and on the toxigenic capability of these isolates in particular.

Environmental factors affect the activity of biocontrol agents against ochratoxigenic Aspergillus carbonarius on wine grape.

PubMed

De Curtis, F; de Felice, D V; Ianiri, G; De Cicco, V; Castoria, R

2012-09-17

The influence of temperature and relative humidity (RH) on the activity of three biocontrol agents-the yeast Metschnikowia pulcherrima LS16 and two strains of the yeast-like fungus Aureobasidium pullulans LS30 and AU34-2-against infection by A. carbonarius and ochratoxin A (OTA) accumulation in wine grape berries was investigated in lab-scale experiments. The presence of wounds on grape skin dramatically favored infection of berries by A. carbonarius strain A1102, since unwounded berries showed very low levels of infection at all conditions of RH and temperature tested. Artificially wounded berries pre-treated with the biocontrol agents were inoculated with the ochratoxigenic A. carbonarius strain A1102 and were incubated for 5 days at two levels of RH (60% and 100%) and three different temperatures (20, 25 and 30 °C). The three biocontrol agents were able to prevent infections at 60% RH and 20 °C. At 60% RH and 25 °C only strain AU34-2 achieved some protection on day 5, whereas at 30 °C a limited biocontrol efficacy was evident only up to day 2. At 100% RH, LS16, LS30 and AU34-2 showed effective protection of grape berries at 20 °C until the 5th day of incubation. The three biocontrol agents achieved significant protection at higher temperatures only until the 2nd day after the beginning of the experiment: all three strains at 25 °C, and only strain LS16 at 30 °C. After 5 days, the three biocontrol agents were able to significantly reduce the level of OTA in berries at all the conditions tested. This occurred even when protection from infection was not significant, except at 30 °C and 100% of RH for all the three strains, and at 25 °C and 100% of RH for strain LS16. The biocontrol agents displayed a higher rate of colonization on grape berries at 20 and 25 °C than at 30 °C. The higher value of RH (100%) appeared to increase the rate of colonization, in particular at 20 and 25 °C. Taken together, our results emphasize the significant influence of environmental factors on the effectiveness of biocontrol against A. carbonarius as well as on OTA contamination in wine grape berries, and the need for biocontrol agents that can cope with the environmental conditions that are conducive to attack by A. carbonarius. Copyright © 2012 Elsevier B.V. All rights reserved.

Maternal, Child Health, and Family Planning Services. Hearings before the Subcommittee on Health and the Environment of the Committee on Energy and Commerce. House of Representatives, One Hundredth Congress, Second Session (February 25, 1988--Healthy Children: Investing in the Future; April 22, 1988--Title X of the Public Health Service Act).

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. House Committee on Energy and Commerce.

Hearings were held to: (1) receive "Healthy Children: Investing in the Future," an Office of Technology Assessment (OTA) study on cost-effective strategies for improving the health of mothers and children; and (2) consider reauthorization of the Federal Family Planning Program (FFPP), Title X of the Public Health Service Act. This…

Diversity of Aspergillus section Nigri on the surface of Vitis labrusca and its hybrid grapes.

PubMed

Ferranti, Larissa de Souza; Fungaro, Maria Helena P; Massi, Fernanda Pelisson; Silva, Josué José da; Penha, Rafael Elias Silva; Frisvad, Jens Christian; Taniwaki, Marta Hiromi; Iamanaka, Beatriz Thie

2018-03-02

This study investigated the presence of Aspergillus species belonging to Aspergillus section Nigri on Vitis labrusca and its hybrid grapes grown in Brazil. The ability of the fungi isolates to produce ochratoxin A (OTA) and fumonisin B 2 (FB 2 ) as well as the presence of these mycotoxins in the grapes were also studied. Eighty-eight samples were collected from the main grape producing states in Brazil: Rio Grande do Sul (n=30), Pernambuco (n=21), São Paulo (n=21) and Paraná (n=16). The highest average contamination level by A. section Nigri occurred on the grapes from Pernambuco (66.3%). A total of 2042 A. section Nigri isolates was analyzed and clustered in three groups according to morphology characterization: A. section Nigri uniseriate (79.3%), A. niger "aggregate" (18.3%) and A. carbonarius (2.4%). In order to precisely identify the Aspergillus species, two hundred and forty-eight strains were subjected to DNA sequencing. Among the A. section Nigri uniseriate group, the following species were found: A. japonicus, A. uvarum, A. brunneoviolaceus, A. aculeatus and A. labruscus. Within the A. niger "aggregate", the following species were found: A.niger sensu stricto, A. welwitschiae and A. vadensis. Regarding mycotoxin-production capacity, 3.2% of the total A. section Nigri isolates (2042) were positive for OTA production and from A. niger "aggregate" (373) tested, 42.1% were FB 2 producers. However, none of the 88 grape samples were contaminated with these mycotoxins. Copyright © 2017. Published by Elsevier B.V.

Shock Treatment: Using Immersive Digital Realism to Restage and Re-examine Milgram’s ‘Obedience to Authority’ Research

PubMed Central

Haslam, S. Alexander; Reicher, Stephen D.; Millard, Kathryn

2015-01-01

Attempts to revisit Milgram’s ‘Obedience to Authority’ (OtA) paradigm present serious ethical challenges. In recent years new paradigms have been developed to circumvent these challenges but none involve using Milgram’s own procedures and asking naïve participants to deliver the maximum level of shock. This was achieved in the present research by using Immersive Digital Realism (IDR) to revisit the OtA paradigm. IDR is a dramatic method that involves a director collaborating with professional actors to develop characters, the strategic withholding of contextual information, and immersion in a real-world environment. 14 actors took part in an IDR study in which they were assigned to conditions that restaged Milgrams’s New Baseline (‘Coronary’) condition and four other variants. Post-experimental interviews also assessed participants’ identification with Experimenter and Learner. Participants’ behaviour closely resembled that observed in Milgram’s original research. In particular, this was evidenced by (a) all being willing to administer shocks greater than 150 volts, (b) near-universal refusal to continue after being told by the Experimenter that “you have no other choice, you must continue” (Milgram’s fourth prod and the one most resembling an order), and (c) a strong correlation between the maximum level of shock that participants administered and the mean maximum shock delivered in the corresponding variant in Milgram’s own research. Consistent with an engaged follower account, relative identification with the Experimenter (vs. the Learner) was also a good predictor of the maximum shock that participants administered. PMID:25730318

Is intramedullary nailing applicable for distal tibial fractures with ankle joint extension?

PubMed

Beytemür, Ozan; Albay, Cem; Adanır, Oktay; Yüksel, Serdar; Güleç, Mehmet Akif

2016-12-01

This study aims to evaluate the functional and radiographic results and treatment complications of AO/OTA (Arbeitsgemeinschaft fur Osteosynthesefragen/Orthopaedic Trauma Association) type 43C1 and C2 fractures treated with intramedullary nailing. We retrospectively evaluated 35 AO/OTA type 43C1 and C2 patients (26 males, 9 females; mean age 39.8±16.9 years; range 19 to 82 years) treated with intramedullary nailing. Two interfragmentary screws out of nail were applied in 10 patients (29%), while one interfragmentary screw out of nail was applied in 17 patients (49%). Intramedullary nailing was applied in eight patients (23%) without external screws. Fracture union, union time, alignment problems, and complications were evaluated. Clinical evaluation of patients was conducted using the Olerud and Molander score and by measuring the ankle joint range of motion. Union was achieved in all 35 patients. Mean union time was 16.5±2.8 weeks (range 12 to 24 weeks) and mean Olerud and Molander score was 88±8.24. Varus deformity was detected in one patient, valgus deformity was detected in two patients, and rotation deformity was detected in one patient. Superficial infection was detected in three patients (9%). Deep infection was not detected in any patient. Intramedullary nailing is not contraindicated for simple intra-articular distal tibial fractures. In these fractures, intramedullary nailing performed in accordance with its technique, with an additional percutaneous screw if necessary, is a successful treatment option with high fracture union rates, high functional results, and low complication rates.

Recovering from "amnesia" brought about by radiation. Verification of the "Over the air" (OTA) application software update mechanism On-Board Solar Orbiter's Energetic Particle Detector

NASA Astrophysics Data System (ADS)

Da Silva, Antonio; Sánchez Prieto, Sebastián; Rodriguez Polo, Oscar; Parra Espada, Pablo

Computer memories are not supposed to forget, but they do. Because of the proximity of the Sun, from the Solar Orbiter boot software perspective, it is mandatory to look out for permanent memory errors resulting from (SEL) latch-up failures in application binaries stored in EEPROM and its SDRAM deployment areas. In this situation, the last line in defense established by FDIR mechanisms is the capability of the boot software to provide an accurate report of the memories’ damages and to perform an application software update, that avoid the harmed locations by flashing EEPROM with a new binary. This paper describes the OTA EEPROM firmware update procedure verification of the boot software that will run in the Instrument Control Unit (ICU) of the Energetic Particle Detector (EPD) on-board Solar Orbiter. Since the maximum number of rewrites on real EEPROM is limited and permanent memory faults cannot be friendly emulated in real hardware, the verification has been accomplished by the use of a LEON2 Virtual Platform (Leon2ViP) with fault injection capabilities and real SpaceWire interfaces developed by the Space Research Group (SRG) of the University of Alcalá. This way it is possible to run the exact same target binary software as if was run on the real ICU platform. Furthermore, the use of this virtual hardware-in-the-loop (VHIL) approach makes it possible to communicate with Electrical Ground Support Equipment (EGSE) through real SpaceWire interfaces in an agile, controlled and deterministic environment.