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1.
Brain Cogn ; 178: 106178, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38823196

ABSTRACT

Creativity has previously been linked with various attentional phenomena, including unfocused or broad attention. Although this has typically been interpreted through an executive functioning framework, such phenomena may also arise from atypical incentive salience processing. Across two studies, we examine this hypothesis both neurally and psychologically. First we examine the relationship between figural creativity and event-related potentials during an audio-visual oddball task, finding that rater creativity of drawings is associated with a diminished P300 response at midline electrodes, while abstractness and elaborateness of the drawings is associated with an altered distribution of the P300 over posterior electrodes. These findings support the notion that creativity may involve an atypical attribution of salience to prominent information. We further explore the incentive salience hypothesis by examining relationships between creativity and a psychological indicator of incentive salience captured by participants' ratings of enjoyment (liking) and their motivation to pursue (wanting) diverse real world rewards, as well as their positive spontaneous thoughts about those rewards. Here we find enhanced motivation to pursue activities as well as a reduced relationship between the overall tendency to enjoy rewards and the tendency to pursue them. Collectively, these findings indicate that creativity may be associated with atypical allocation of attentional and motivational resources to novel and rewarding information, potentially allowing more types of information access to attentional resources and motivating more diverse behaviors. We discuss the possibility that salience attribution in creatives may be less dependent on task-relevance or hedonic pleasure, and suggest that atypical salience attribution may represent a trait-like feature of creativity.


Subject(s)
Attention , Creativity , Electroencephalography , Motivation , Humans , Male , Female , Motivation/physiology , Attention/physiology , Young Adult , Electroencephalography/methods , Adult , Event-Related Potentials, P300/physiology , Evoked Potentials/physiology , Brain/physiology , Reward , Adolescent
2.
Trends Cogn Sci ; 28(7): 597-599, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38849285

ABSTRACT

Creativity often entails gaining a novel perspective, yet it remains uncertain how this is accomplished. Atypical salience processing may foster creative thinking by prioritizing putatively irrelevant information, thereby broadening the material accessible for idea generation and inhibiting attentional fixedness; in essence, motivating creative individuals to incorporate information that others overlook.


Subject(s)
Attention , Creativity , Humans , Attention/physiology , Thinking/physiology
3.
J Psychopharmacol ; 36(3): 348-359, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35105186

ABSTRACT

BACKGROUND: Controversy surrounds psychedelics and their potential to boost creativity. To date, psychedelic studies lack a uniform conceptualization of creativity and methodologically rigorous designs. AIMS: This study aimed at addressing previous issues by examining the effects of lysergic acid diethylamide (LSD) on creativity using multimodal tasks and multidimensional approaches. METHODS: In a randomized, double-blind, placebo-controlled, crossover study, 24 healthy volunteers received 50 µg of LSD or inactive placebo. Near drug peak, a creativity task battery was applied, including pattern meaning task (PMT), alternate uses task (AUT), picture concept task (PCT), creative metaphors task (MET) and figural creativity task (FIG). Creativity was assessed by scoring creativity criteria (novelty, utility, surprise), calculating divergent thinking (fluency, originality, flexibility, elaboration) and convergent thinking, computing semantic distances (semantic spread, semantic steps) and searching for data-driven special features. RESULTS: LSD, compared to placebo, changed several creativity measurements pointing to three overall LSD-induced phenomena: (1) 'pattern break', reflected by increased novelty, surprise, originality and semantic distances; (2) decreased 'organization', reflected by decreased utility, convergent thinking and, marginally, elaboration; and (3) 'meaning', reflected by increased symbolic thinking and ambiguity in the data-driven results. CONCLUSION: LSD changed creativity across modalities and measurement approaches. Three phenomena of pattern break, disorganization and meaning seemed to fundamentally influence creative cognition and behaviour pointing to a shift of cognitive resources 'away from normal' and 'towards the new'. LSD-induced symbolic thinking might provide a tool to support treatment efficiency in psychedelic-assisted therapy.


Subject(s)
Hallucinogens , Lysergic Acid Diethylamide , Creativity , Cross-Over Studies , Hallucinogens/pharmacology , Humans , Lysergic Acid Diethylamide/pharmacology , Thinking
4.
Neuroimage ; 202: 116125, 2019 11 15.
Article in English | MEDLINE | ID: mdl-31461678

ABSTRACT

What is the relationship between creativity, curiosity, and schizotypy? Schizophrenia-spectrum conditions and creativity have been linked to deficits in filtering sensory information, and curiosity is associated with information-seeking. This raises the possibility of a perception-based link between all three concepts. Here, we investigated whether the same individual differences in perceptual encoding explain variance in creativity, curiosity, and schizotypy. We administered an active auditory oddball task and a free viewing eye-tracking paradigm (N = 88). Creativity was measured with the figural portion of the Torrance Tests of Creative Thinking (TTCT) and two self-report scales. Schizotypy and curiosity were measured with self-reports. We found that creativity was associated with increased reaction time to the rare tone in the oddball task and was positively associated with the number and duration of fixations in the free viewing task. Schizotypy, on the other hand, showed a negative trend with the number and duration of fixations. Both creativity and curiosity were positively associated with explorative eye movements (unique number of regions visited) and Shannon entropy, while schizotypy was negatively associated with entropy. We further compared saliency maps finding that individuals high versus low in creativity and curiosity, respectively, exhibit differences in where they look. These findings may suggest a perception-based link between creativity and curiosity, but not schizotypy. Implications and limitations of these findings are discussed.


Subject(s)
Auditory Perception/physiology , Creativity , Exploratory Behavior/physiology , Eye Movements/physiology , Individuality , Schizotypal Personality Disorder/physiopathology , Visual Perception/physiology , Adolescent , Adult , Entropy , Eye Movement Measurements , Female , Humans , Male , Young Adult
5.
Mycotoxin Res ; 35(1): 83-87, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30343381

ABSTRACT

The applicability of enzyme immunoassays (EIA) for aflatoxin M1 (AFM1), ochratoxin A (OTA) and zearalenone (ZEN) to analyse these toxins in donkey milk (Equus asinus) was studied. For AFM1 and OTA analysis, milk could be analysed by EIA without sample pretreatment. For ZEN, heat treatment at 78 °C for 30 min prior EIA analysis was required to avoid false positives. To include detection of phase II metabolites of ZEN, samples were additionally treated with glucuronidase/sulfatase for this EIA. Detection limits were 5 ng/kg (AFM1), 9 ng/kg (OTA) and 600 ng/kg (ZEN). All donkey milk samples were negative for all three toxins. Satisfactory quantitation was achieved for spiked samples. Analysis of some cereal-containing donkey feed components (pellets, oats) by EIA revealed absence of aflatoxin B1 (AFB1, < 3 µg/kg) and OTA (< 4 µg/kg), while ZEN was found in pellets (180 µg/kg) and in oats (7 µg/kg). This is the first one study on multitoxin determination in donkey milk by antibody-based test systems. In general, the results confirm that EIAs are convenient tools for mycotoxin detection in donkey milk. However, false-positive results may occur, possibly due to the high lysozyme content of donkey milk, which may exert inhibitory activity in some competitive EIA systems. Therefore, specific validation of each EIA for this specific matrix is required, and re-analysis after heat treatment of EIA-positive donkey milk is highly recommended.


Subject(s)
Immunoenzyme Techniques , Milk , Mycotoxins/analysis , Aflatoxin B1/analysis , Aflatoxin M1/analysis , Animal Feed/analysis , Animals , Chromatography, High Pressure Liquid , Equidae , False Positive Reactions , Food Contamination/analysis , Hot Temperature , Limit of Detection , Muramidase
6.
Head Neck ; 40(12): 2685-2694, 2018 12.
Article in English | MEDLINE | ID: mdl-30456890

ABSTRACT

BACKGROUND: Cortactin (CTTN) is located on chromosome 11q13 and is associated with invasiveness in various cancer entities. CTTN protein expression could be a prognosticator of oral squamous cell carcinoma (OSCC) in terms of recurrence and survival. METHODS: CTTN-dependent invasion was performed using migration assay in human papillomavirus-negative head and neck squamous cell carcinoma (HNSCC) cells. Cortactin protein analysis in tissue microarrays was used for correlation with clinical parameters, as well as for survival analysis. Gene expression profiling in HNSCC cells was performed to unreveal CTTN signaling. RESULTS: Knockdown of CTTN in HNSCC cells showed less invasion in vitro. Gene expression profiling showed various deregulated genes known to be involved in progression. We confirmed the link between CTTN overexpression and progression in a large clinical cohort. High expression was associated with worse overall and progression-free survival. CONCLUSIONS: We propose CTTN for managing OSCC in terms of adjuvant therapy and aftercare. Furthermore, our study reveals new potential targets in CTTN signaling for individualized OSCC therapy.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Cortactin/metabolism , Mouth Neoplasms/metabolism , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/surgery , Cell Line, Tumor , Cortactin/genetics , Disease Progression , Female , Gene Expression Profiling , Gene Knockdown Techniques , Humans , Male , Motilin/antagonists & inhibitors , Mouth Neoplasms/mortality , Mouth Neoplasms/surgery , Protein Array Analysis , Retrospective Studies , Signal Transduction , Survival Analysis
7.
J AOAC Int ; 101(3): 618-626, 2018 May 01.
Article in English | MEDLINE | ID: mdl-28964275

ABSTRACT

Four sets of polyclonal antibodies against ergot alkaloids ergometrine, ergotamine, α-ergocryptine, and ergocornine were produced and characterized in a competitive direct or indirect enzyme immunoassay (EIA). Standard curve LODs were 0.03 ng/mL (ergometrine EIA) to 2.0 ng/mL (ergocornine EIA). Three EIAs were highly specific, whereas the ergometrine EIA had a broad specificity pattern and reacted, albeit weakly, with all seven major ergot alkaloids and their epimeric forms. Using the ergometrine EIA, a generic test system was established in which total ergot alkaloids are quantified by a standard curve for a toxin mixture composed of three alkaloids that matched the ergot alkaloid composition in naturally contaminated rye and wheat products. Sample extraction with acetonitrile-phosphate-buffered saline at pH 6.0 without further cleanup was sufficient for EIA analysis. The LODs for total ergot alkaloids were 20 ng/g in rye and wheat flour and 14 ng/g in bread. Recoveries were 85-110% (RSDs of 0.1-11.7%) at a concentration range of 50-1000 ng/g. The total ergot alkaloid EIA was validated by comparison with HPLC-fluorescence detection. Although some under- and overestimation by the total ergot alkaloid EIA was observed, it was suitable for the reliable identification of positive samples at 10-20 ng/g and for the determination of total ergot alkaloids in a concentration range between 100 and 1000 ng/g.


Subject(s)
Bread/analysis , Edible Grain/chemistry , Ergot Alkaloids/analysis , Flour/analysis , Food Contamination/analysis , Immunoenzyme Techniques/methods , Animals , Antibodies/immunology , Bread/microbiology , Edible Grain/microbiology , Ergot Alkaloids/immunology , Flour/microbiology , Limit of Detection , Rabbits
8.
J Agric Food Chem ; 66(1): 315-322, 2018 Jan 10.
Article in English | MEDLINE | ID: mdl-29237259

ABSTRACT

Limited availability of toxin standards for lolitrem B and ergovaline impedes routine control of grasses for endophyte toxins. This study aimed at assessing the applicability of an enzyme immunoassay (EIA) for the indole-diterpene mycotoxin paxilline, in combination with a generic EIA for ergot alkaloids, as alternative parameters for screening purposes. Analysis of grass seeds and model pastures of four different grass species showed that both EIAs yielded highly positive results for paxilline and ergot alkaloids in perennial ryegrass seeds. Furthermore, evidence for natural occurrence of paxilline in grass in Germany was obtained. High performance liquid chromatography-tandem mass spectrometry analysis qualitatively confirmed the paxilline EIA results but showed that paxilline analogues 1'-O-acetylpaxilline and 13-desoxypaxilline were the predominant compounds in seeds and grass. In the absence of easily accessible reference standards for specific analysis of some major endophyte toxins, analysis of paxilline and ergot alkaloids by EIA may be suitable substitute parameters. The major advantage of this approach is its ease of use and speed, providing an analytical tool which could enhance routine screening for endophyte toxins in pasture.


Subject(s)
Ergot Alkaloids/analysis , Immunoassay/methods , Indoles/analysis , Mycotoxins/analysis , Poaceae/chemistry , Seeds/chemistry , Animal Feed/analysis , Food Contamination/analysis
9.
Anal Bioanal Chem ; 409(21): 5101-5112, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28674820

ABSTRACT

A newly developed enzyme immunoassay (EIA) for the detection of the tremorgenic indole-diterpene alkaloid paxilline (PAX) and closely related analogs was used to analyze ergot sclerotia collected from rye and barley fields. The mean EIA standard curve detection limit was 0.47 ± 0.14 ng/mL; relative cross-reactivity of toxin standard solutions was found for 11-hydroxy-paspaline (terpendole E, 1.1%) but not for lolitrem B or ergot alkaloids. Sclerotia from all fields were positive in the PAX-EIA at concentration levels of 620 ± 200 and 160 ± 37 µg/kg in ergot of rye and 130 ± 47 µg/kg in ergot of barley. Confirmatory analyses of sclerotia by liquid chromatography-tandem mass spectrometric detection identified PAX and its analog 13-desoxypaxilline. To the best of our knowledge, this is the first report on the natural occurrence of tremorgenic indole-diterpene alkaloid mycotoxins in ergot sclerotia from rye and barley. Along with details on the analytical methodology developed in this study, particularly PAX-antibody production, the relevance and implications of these findings for food and feed safety are discussed. Presence or absence of elevated levels of tremorgenic mycotoxins, along with the ergot alkaloids, would help in explaining the difference between the two distinct manifestations of historic ergotism, the convulsive and the gangrenous form. Further method development for paxilline and other tremorgenic mycotoxins in cereals used for food and feed is a prerequisite for a comprehensive risk assessment, which seems to be necessary in light of the findings reported here. Paxilline in ergot of rye.


Subject(s)
Hordeum/chemistry , Indoles/analysis , Mycotoxins/analysis , Secale/chemistry , Tremor/chemically induced , Animal Feed/analysis , Chromatography, Liquid/methods , Food Contamination , Immunoenzyme Techniques , Indoles/toxicity , Limit of Detection , Mycotoxins/toxicity , Tandem Mass Spectrometry/methods
10.
Food Microbiol ; 65: 44-50, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28400018

ABSTRACT

Cronobacter spp. cause infant disease, several cases have been associated with powdered infant formulae (PIF). In the early 2000s, contamination of German PIF with these opportunistic pathogens was quite common. Before 2008, all isolates Cronobacter spp. had been classified as Enterobacter sakazakii, therefore little is known about species diversity within such isolates. Genetic, serologic, and biochemical traits of 80 Cronobacter isolates, originally obtained 2003-2006 within infant food surveys in Germany, were reassessed in this study. By sequencing of the fusA gene, all isolates were unambiguously assigned to two species, C. sakazakii (n = 73) and C. malonaticus (n = 7). PCR serotyping identified five C. sakazakii serotypes and two C. malonaticus serotypes, biochemical profiling yielded five biogroups. PFGE analysis also showed high heterogeneity in both species. Multilocus sequence typing of 26 selected isolates yielded 16 different sequence types (ST), including C. sakazakii ST 1 (n = 6) and the highly virulent ST 4 (n = 2). The results suggest that just two, but highly heterogeneous species were responsible for the Cronobacter contamination problem which challenged the German PIF industry in the beginning of this century. This fact may have influenced the success of efforts to identify and eliminate sources of contamination.


Subject(s)
Cronobacter sakazakii/isolation & purification , Cronobacter/classification , Cronobacter/genetics , Food Microbiology , Infant Formula/microbiology , Bacterial Typing Techniques , Cronobacter/isolation & purification , Cronobacter sakazakii/classification , Cronobacter sakazakii/genetics , Genotype , Germany , Humans , Infant , Multilocus Sequence Typing , Peptide Elongation Factor G/genetics , Polymerase Chain Reaction , Retrospective Studies , Serotyping
11.
Mycotoxin Res ; 33(1): 75-78, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27957687

ABSTRACT

An enzyme-linked immunosorbent assay (ELISA) for the Alternaria mycotoxin tenuazonic acid (TeA) was evaluated by comparative analysis of naturally contaminated sorghum grains and sorghum-based infant food, using a stable isotope dilution LC-MS assay (SIDA; limit of detection (LOD) 1.0 µg/kg) as the reference method. LODs of the ELISA were 30 µg/kg in sorghum grains and 220 µg/kg in sorghum-based infant cereals. With SIDA, 100% of the samples (n = 28) had been positive for TeA in a concentration range of 6-584 µg/kg (mean 113 µg/kg). The ELISA consistently detected TeA in all naturally contaminated samples at cut-off levels of 30-60 µg/kg (sorghum) and 200-300 µg/kg (infant cereals), as based on corresponding to SIDA values. Although the ELISA was much less sensitive than the SIDA method, it may be useful as a screening method for sorghum and sorghum-based infant foods and can be employed to identify samples containing elevated concentrations of TeA in food, well below the proposed level of concern (500 µg/kg).


Subject(s)
Food Safety/methods , Immunoenzyme Techniques/methods , Infant Food/analysis , Mycotoxins/analysis , Sorghum/chemistry , Tenuazonic Acid/analysis , Antibiotics, Antineoplastic , Chromatography, Liquid , Humans , Mass Screening/methods , Mass Spectrometry , Sensitivity and Specificity
12.
Mycotoxin Res ; 32(1): 1-5, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26420604

ABSTRACT

Brewer's yeasts are rich in vitamins of the B-group and contain other nutritive factors; therefore, they are recommended as valuable food supplements for people with special dietary requirements like pregnant women, children, and adolescents, or for people with high physical activity. Additionally, certain strains of brewer's yeast are known to be capable of adsorbing xenobiotics such as mycotoxins. Because of that, these yeasts are regarded as having positive effects in food, beverage, and feed technology. Their potential to bind mycotoxins such as ochratoxin A (OTA), however, can subsequently lead to a contamination of such brewer's yeasts used as food supplements. In the present study, we analyzed 46 samples of brewer's yeasts for the occurrence of OTA by HPLC with fluorescence detector (HPLC-FLD) and for confirmatory measurements by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Nearly 90% of the samples were contaminated with OTA, the levels ranging from the limit of detection (LOD, 0.01 µg/kg) to 4.2 µg/kg. The mean and median levels of contamination were 0.49 and 0.27 µg/kg, respectively. Based on these results, the additional weekly OTA exposure by regularly consuming such supplements was assessed. Depending on different subpopulations (adults, children) and levels of contamination used for calculation, the additional OTA intake via brewer's yeast products ranged from 9.3% (mean case) to 114% (worst case) of the published mean weekly OTA intake in Germany (adults 279.3 ng, children 195.3 ng). At present, maximum levels for OTA in nutritional supplements like brewer's yeast do not exist. Based on our results, however, it is recommended that producers of these dietary supplements should include mycotoxin analyses in ongoing and future self-monitoring programs and in product quality checks.


Subject(s)
Dietary Supplements/analysis , Ochratoxins/analysis , Saccharomyces cerevisiae/chemistry , Chromatography, Liquid , Germany , Humans , Tandem Mass Spectrometry
13.
J Food Sci ; 80(12): M2860-7, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26509868

ABSTRACT

The microbiological quality of 132 dried pasta products available on the German market, originating from 11 different countries, was studied. Sample materials included soft or durum wheat products, some of which produced with other ingredients such as eggs, spices, or vegetables. Parameters included hygiene indicators (aerobic plate count, mold count, the presence of Enterobacteriaceae) and pathogenic/toxinogenic bacterial species (Salmonella spp., Staphylococcus aureus, presumptive Bacillus cereus, and Cronobacter spp.). The overall results of hygiene parameters indicated a satisfactory quality. Salmonella was not found in any sample. Three samples were positive for S. aureus (10(2) to 10(4) colony forming unit (CFU)/g). Presumptive B. cereus at levels of 10(3) to 10(4) CFU/g were detected in 3 samples. Cronobacter spp. were isolated from 14 (10.6%) products. Of these, 9 isolates were identified as C. sakazakii, 2 each as C. turicensis and C. malonaticus, and 1 as C. muytjensii. The isolates were assigned to 9 multilocus sequence typing (MLST) sequence types and to 14 different PFGE profiles. Although pasta products are typically cooked before consumption, some consumers, and children in particular, may also eat raw pasta as nibbles. Raw pasta seems to be a relevant source of exposure to dietary Cronobacter spp., although health risks are probably restricted to vulnerable consumers. High numbers of presumptive B. cereus as found in some samples may be a risk after improper storage of cooked pasta products because toxinogenic strains are frequently found within this species.


Subject(s)
Bacteria/growth & development , Cooking , Cronobacter/growth & development , Food Microbiology , Foodborne Diseases/microbiology , Bacillus cereus/growth & development , Bacteria/isolation & purification , Child , Cronobacter/isolation & purification , Desiccation , Eggs/microbiology , Enterobacteriaceae/growth & development , Flour/microbiology , Germany , Humans , Multilocus Sequence Typing , Salmonella/growth & development , Species Specificity , Spices/microbiology , Staphylococcus aureus/growth & development , Triticum , Vegetables/microbiology
14.
Mycotoxin Res ; 31(4): 177-83, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26388046

ABSTRACT

The ergoline alkaloid fumigaclavine A (FuA) is one of the major mycotoxins produced by Aspergillus fumigatus, the main causative fungal agent of avian aspergillosis. To study in situ production of FuA, post-mortem respiratory tissues of various avian species, as well as blood samples of falcons (Falco sp.), were analysed by enzyme immunoassay (EIA). At a detection limit of 1.5 ng/ml, FuA EIA positive results were obtained for tissue samples from seven (64%) out of 11 birds with confirmed aspergillosis, with a maximum concentration of 38 ng/g, while all controls (n = 7) were negative. No FuA could be detected in blood serum (detection limit 0.7 ng/ml) of 15 falcons, experimentally inoculated with A. fumigatus conidia. Fungal mycelium material from tissue of clinical aspergillosis cases, cultured on malt extract agar, was highly positive in the FuA EIA in milligrams per gram range. Chromatographic analysis of mycelium extracts revealed the co-presence of FuA and the structurally related fumigaclavine C (FuC). Alkaline hydrolysis of FuA and FuC yielded the corresponding deacetylation products, FuB and FuE. This is the first report showing that fumigaclavine alkaloids are produced by A. fumigatus in situ during the course of clinical aspergillosis in birds; however, the role of these compounds in the pathogenesis of this disease is still unknown.


Subject(s)
Aspergillosis/veterinary , Bird Diseases/pathology , Mycotoxins/analysis , Mycotoxins/blood , Animals , Aspergillosis/pathology , Aspergillus fumigatus/growth & development , Aspergillus fumigatus/isolation & purification , Aspergillus fumigatus/metabolism , Chromatography , Ergot Alkaloids/analysis , Ergot Alkaloids/blood , Ergot Alkaloids/chemistry , Falconiformes , Immunoenzyme Techniques , Indole Alkaloids/analysis , Indole Alkaloids/blood , Indole Alkaloids/chemistry , Mycotoxins/chemistry , Respiratory System/chemistry , Serum/chemistry
15.
Foodborne Pathog Dis ; 12(7): 585-90, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26135892

ABSTRACT

Bulk tank milk from 80 dairy farms located in the West Java Region of Indonesia was analyzed for the presence of extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae. Isolates from seven dairy farms were ESBL positive, and all were identified as Klebsiella pneumoniae. The isolates showed ESBL-characteristic antibiotic resistance patterns. Further analysis revealed that all K. pneumoniae isolates harbored the blaSHV gene, and two isolates were additionally positive for the blaTEM-1 and blaCTX-M-15 genes. Isolates from different farms were clonally diverse according to macrorestriction analysis. The results indicate that the relatively high frequency of ESBL-producing K. pneumoniae in bulk tank milk implies the risk that milk is both a source of local exposure and a vector contributing to the supraregional spread of antibiotic-resistant bacteria by trade.


Subject(s)
Food Contamination/analysis , Klebsiella pneumoniae/isolation & purification , Milk/microbiology , Animals , Chromosomes, Bacterial/genetics , Colony Count, Microbial , DNA, Bacterial/genetics , Dairying , Drug Resistance, Multiple, Bacterial , Food Microbiology , Genes, Bacterial , Indonesia , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/metabolism , Microbial Sensitivity Tests , beta-Lactamases/metabolism
16.
Mol Oncol ; 9(8): 1704-19, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26040981

ABSTRACT

Recurrent gain on chromosome 3q26 encompassing the gene locus for the transcription factor SOX2 is a frequent event in human squamous cell carcinoma, including head and neck squamous cell carcinoma (HNSCC). Numerous studies demonstrated that SOX2 expression and function is related to distinct aspects of tumor cell pathophysiology. However, the underlying molecular mechanisms are not well understood, and the correlation between SOX2 expression and clinical outcome revealed conflicting data. Transcriptional profiling after silencing of SOX2 expression in a HNSCC cell line identified a set of up-regulated genes related to cell motility (e.g. VIM, FN1, CDH2). The inverse regulation of SOX2 and aforementioned genes was validated in 18 independent HNSCC cell lines from different anatomical sites. The inhibition of cell migration and invasion by SOX2 was confirmed by constant or conditional gene silencing and accelerated motility of HNSCC cells after SOX2 silencing was partially reverted by down-regulation of vimentin. In a retrospective study, SOX2 expression was determined by immunohistochemical staining on tissue microarrays containing primary tumor specimens of two independent HNSCC patient cohorts. Low SOX2 expression was found in 19.3% and 44.9% of primary tumor specimens, respectively. Univariate analysis demonstrated a statistically significant correlation between low SOX2 protein levels and reduced progression-free survival (Cohort I 51 vs. 16 months; Cohort II 33 vs. 12 months) and overall survival (Cohort I 150 vs. 37 months; Cohort II 33 vs. 16 months). Multivariate Cox proportional hazard model analysis confirmed that low SOX2 expression serves as an independent prognostic marker for HNSCC patients. We conclude that SOX2 inhibits tumor cell motility in HNSCC cells and that low SOX2 expression serves as a prognosticator to identify HNSCC patients at high risk for treatment failure.


Subject(s)
Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/mortality , Cell Movement/genetics , Gene Deletion , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/mortality , SOXB1 Transcription Factors/genetics , Vimentin/genetics , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/therapy , Cell Line, Tumor , Down-Regulation , Female , Gene Expression Regulation, Neoplastic , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/therapy , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , SOXB1 Transcription Factors/metabolism , Squamous Cell Carcinoma of Head and Neck , Survival Analysis , Vimentin/metabolism
17.
J Agric Food Chem ; 59(23): 12317-22, 2011 Dec 14.
Article in English | MEDLINE | ID: mdl-22054343

ABSTRACT

The Alternaria mycotoxin tenuazonic acid was derivatized with succinic anhydride and conjugated to keyhole limpet hemocyanin (KLH) and to horseradish peroxidase (HRP), respectively. The KLH conjugate was used to produce polyclonal antibodies in rabbits. A competitive direct enzyme immunoassay (EIA) for tenuazonic acid was established, which was moderately sensitive for tenuazonic acid [50% inhibition concentration (IC(50)): 320 ± 130 ng/mL] but strongly reacted with tenuazonic acid acetate (IC(50): 23.3 ± 7.5 ng/mL). Therefore, an optimized EIA protocol was established, which employed acetylation of standard and sample extract solutions. The mean standard curve detection limit (IC(30)) for tenuazonic acid acetate was 5.4 ± 2.0 ng/mL, enabling detection limits for tenuazonic acid in apple and tomato products of 25-50 ng/g (150 ng/g in tomato paste). Recoveries in a concentration range of 50-2000 ng/g were 60-130% in apple juice and tomato juice and 40-150% in other tomato products. Tenuazonic acid was detected in apple juice and tomato products from German retail shops at levels of 50-200 ng/g. In conclusion, this novel EIA for tenuazonic acid could be useful within a screening program for Alternaria mycotoxins in food.


Subject(s)
Food Contamination/analysis , Fruit/chemistry , Immunoenzyme Techniques/methods , Malus , Solanum lycopersicum , Tenuazonic Acid/analysis , Animals , Antibodies , Beverages/analysis , Rabbits/immunology
18.
Carcinogenesis ; 32(11): 1734-40, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21900212

ABSTRACT

Soluble sulfotransferases (SULTs) generate electrophilically reactive metabolites from numerous food-borne compounds, environmental contaminants and drugs, often resulting in mutagenicity and carcinogenicity. Substrate specificity, regulation and tissue distribution of SULTs show large interspecies differences. In humans, therefore, SULTs may be involved in the induction of cancer in different tissues than in standard animal models. To construct a rodent model taking some species differences into account, we transferred a 68.5 kb human (h) genomic sequence that comprised the transcribed and long flanking regions of SULT1A1 and 1A2 into murine oocytes. This approach resulted in several mouse lines expressing these human genes in a copy number-dependent manner with a tissue distribution similar to that in humans. In previous in vitro studies, we had demonstrated that human SULT1A1 and 1A2 efficiently catalyze the terminal activation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) to a mutagen. The transgenic mice were used to study the hSULT1A1/1A2-mediated activation. Tissue distribution and levels of DNA adducts were determined in hSULT1A1/1A2 transgenic and wild-type mice after an oral dosage of PhIP. Transgenic mice exhibited significantly elevated PhIP-DNA adduct levels compared with the wild-type in liver (13-fold), lung (3.8-fold), colon (2-fold), kidney (1.6-fold) and cecum (1.5-fold). Moreover, among the eight tissues examined, liver was the one with the lowest and highest adduct levels in wild-type and transgenic mice, respectively. Hence, expression of hSULT1A1/1A2 not only enhanced the genotoxicity but also substantially changed the organotropism of PhIP.


Subject(s)
Arylsulfotransferase/physiology , DNA Adducts/metabolism , Imidazoles/metabolism , Animals , DNA Damage , Female , Gene Dosage , Genotype , Humans , Immunoblotting , Male , Mice , Mice, Transgenic , Tissue Distribution
19.
J Agric Food Chem ; 59(12): 6360-8, 2011 Jun 22.
Article in English | MEDLINE | ID: mdl-21534631

ABSTRACT

This study investigated the production of polyclonal (pAB) antibodies and the first time production of monoclonal (mAB) antibodies against the mycotoxin alternariol, and their implementation in enzyme immunoassay (EIA) for the rapid determination of alternariol in foods. Both EIAs were highly sensitive, with detection limits (IC20) of 35 ± 6.9 pg/mL (mAb EIA) and 59 ± 16 pg/mL (pAb EIA). Food products (n = 109; apple and tomato products, white wine) from German retail shops were analyzed. At a detection limit of 1-2 µg/kg, alternariol at 1-13 µg/kg was found with high frequency in apple (67%) and tomato (93%) products. Tomatoes with visible signs of Alternaria infection, stored at room temperature for up to 4 weeks, contained alternariol at levels up to 50 mg/kg, as determined by EIA and HPLC-FLD. It is concluded that the alternariol immunoassays present a versatile screening tool which could facilitate food control for Alternaria toxins.


Subject(s)
Immunoenzyme Techniques/methods , Lactones/analysis , Malus/chemistry , Mycotoxins/analysis , Solanum lycopersicum/chemistry , Antibodies/analysis , Antibodies, Monoclonal/analysis , Food Contamination/analysis , Immunoenzyme Techniques/instrumentation
20.
Methods Mol Biol ; 659: 291-8, 2010.
Article in English | MEDLINE | ID: mdl-20809321

ABSTRACT

With the progress of array technologies and the enabled screening of individual human genomes, a new kind of polymorphism has been described - the so-called copy number variation (CNV) polymorphism. Copy number variants can be found in around 12% of the human genome sequence and have a size of up to several hundred kilobase pairs. These variants can not only differ between individuals, but also between corresponding alleles on homologous chromosomes. We recently developed a cytological assay for parental origin determination that relies on the design of CNV-based sets of probes for fluorescence in situ hybridization (POD-FISH). Here we describe an improved POD-FISH protocol that exploits "high frequency" variants for better discrimination of homologous chromosomes.


Subject(s)
DNA Copy Number Variations/genetics , In Situ Hybridization, Fluorescence/methods , Parents , Fluorescent Dyes/metabolism , Humans , Nucleic Acid Denaturation
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