Search

Background: Fish and fish products are one of the most important food sources of high commercial interest. The global food trade and the associated risks are constantly presenting new challenges to consumer protection and public authorities, which, among other things, demand state-of-the-art analytical methods to ensure food authenticity. Objective: The establishment of MS-based strategies plays a decisive role alongside the (further) development of ELISAor DNA-oriented methods. Methods: In the present work, therefore, the development and in-house validation of an LC-MS and LC-MS/MS-based assay for authenticity testing of certain fish species is described. Results: Based on the execution of a validated bottom-up LC-electrospray-MS and MS/MS assay and multivariate analysis, the commercially available species Lutjanus malabaricus (red snapper) and Sebastes spp. (redfish) are distinguished from each other, whereas an additional 68 samples [nine additional marine species such as pangasius (Pangasianodon hypophthalmus), salmon (Salmo salar), turbot (Scophthalmus maximus), plaice (Pleuronectes platessa), sole (Solea solea), lemon sole (Glyptocephalus cynoglossus), halibut (Reinhardtius hypoglossoides), red salmon (Oncorhynchus nerka), and great scallop (Pecten jacobaeus)] served as blinded negative controls to ensure the specificity of the assay. Conclusions and Highlights: A promising LC-MS and LC-MSMS based assay has been developed that could enable the detection of fish fraud at the protein level in the future. [ABSTRACT FROM AUTHOR]

Leaching processes are responsible for the release of biocides from treated materials into the environment. Adequate modeling of emission processes is required in order to predict emission values in the framework of the risk assessment of biocidal products intended for long-term service life. Regression approaches have been applied to data obtained from the long-term monitoring of biocide emissions in experiments involving semi-field conditions. Due to the complex interaction of different underlying mechanisms such as water and biocide diffusion and desorption, however, these attempts have proven to be of limited usefulness – at least, for the available biocide emission data. It seems that the behavior of the biocide emission curve depends to a considerable extent on whichever underlying mechanism is slowest at a given point in time, thus limiting the amount of biocide available for release. Building on results obtained in the past few years, the authors propose a criterion for determining which mechanism controls the leaching process at a given point in time based on the slope of the log-log emission curve. In addition, a first-order approximation of this slope value is presented which displays advantages both in terms of computability and interpretability. Finally, an algorithm for the determination of breakpoints in the slope of the log-log emission curve is presented for the demarcation of phases within which one mechanism acts as a limiting factor. Image 1 • The usefulness of regression approaches to model leaching processes is limited. • Controlling mechanisms are identified via slope values of log-log emission curves. • A promising expression for these slope values is derived. • Breakpoints in emission curves can be identified by maximum likelihood estimation. [ABSTRACT FROM AUTHOR]

Abstract: The piezoresistive effects of nickel–carbon thin films, i.e., the sensitivity to hydrostatic pressure and uniform strain, are investigated in this study. Thin films, which were obtained by reactive sputtering processes with thicknesses up to 1200nm, exhibit pressure sensitivity coefficients (PCR) about −20ppm/bar and gauge factors up to 30 on Si/SiO2 substrates. A linear change of the thin film''s resistance in respect to the applied hydrostatic pressure was observed. Additionally, the temperature coefficients of resistance were determined in the range of −300 to 0ppm/K, while the temperature coefficient of the PCRs was obtained as good as 0ppm/K. [Copyright &y& Elsevier]

Abstract: Ni:a-C:H thin films obtained by reactive sputtering processes were investigated using EXAFS and subsequent wavelet analysis. Depending on overall thin film deposition conditions, the clusters of Ni in Ni:a-C:H can appear as fcc-Ni or as a non-fcc-Ni phase, such as hcp-Ni or Ni3C. While hcp-Ni and Ni3C are hardly distinguishable by XRD, the EXAFS analysis can reveal if carbon is the nearest neighbour of Ni or not, thus if Ni3C is present or hcp-Ni. Our study showed that wavelet transformation analysis of the EXAFS data is necessary to discriminate clearly between hcp-Ni and Ni3C regarding the presence or absence of carbon coordination shells around the X-ray absorbing Ni atoms. Furthermore, we are confident to have identified Ni3C in our thin films, however, we cannot exclude the possibility of the co-existence of hcp-Ni. Finally, calculations of XRD peaks of hcp-Ni and Ni3C showed that a discrimination of these two crystal phases might be feasible when the crystallite size is increased beyond 40nm. [Copyright &y& Elsevier]

The article discusses a research study on developing an approach for approximating reliability of precision data from laboratory-to-laboratory for the assessment of test methods. The margin of relative error (MRE) was introduced as an approach for obtaining the magnitude of uncertainty but limitations were seen as to underestimates of actual data variability due to negative bias disregard. Conclusions indicated more conservative approximation with the margin of relative random error (MRRE).

Abstract: Nickel containing amorphous hydrogenated carbon (Ni:a-C:H) thin films prepared by reactive sputtering have a high potential for use as piezoresistive sensors. Investigations by means of X-ray diffraction (XRD), transmission electron microscopy, energy-dispersive X-ray spectroscopy, and magnetic characterizations indicate that sputtering parameters and heat treatment influence the film composition, the microscopic structure, and some relevant macroscopic physical properties. The films are heterogeneous in nature and consist of either nanometer sized hcp nickel, nickel carbide (these phases being indistinguishable by XRD), or fcc nickel clusters encapsulated by graphite-like carbon shells. The nature of the metal clusters in the thin films has a strong effect on its magnetic properties. For approximately 55at.% Ni the electrical resistivity of the film is nearly temperature independent over a broad temperature range from 100K to 400K. The strain sensitivity, with a gauge factor of 20, is up to ten times higher than conventional temperature independent strain sensitive films. Compared to industry standard NiCr functional layers used for pressure sensors, Ni:a-C:H films provide a ten fold higher output signal. [Copyright &y& Elsevier]

Abstract: Piezoresistors of polycrystalline silicon were obtained by the aluminum induced crystallization (AIC) process-route. Tri-layer samples with the layer sequence Si/Al/Si were deposited by means of e-beam evaporation. The Si layer thickness was held constant at 300nm, whereas the Al thickness was varied between 25 and 125nm. The annealing was performed in vacuum at temperatures between 330 and 660°C for up to 6h. The piezoresistors exhibit gauge factors (GFs) of 4.5 up to 17, with temperature coefficients of resistance (TCR) between −0.4 and −0.1%/K and temperature coefficients of GF (TCGF) between −0.1 and 0.4%/K. These values depend on the annealing conditions applied and the Al layer thickness of the sample. Complementary measurements on a bi-layer system of Al/Si=300nm/300nm were performed after annealing under vacuum conditions and a subsequent wet-etch removal of the Al top-layer. GFs up to 24, TCRs of −0.4 to −0.2%/K, and TCGFs of −0.2 to 0.2%/K were determined for these samples. As piezoresistive AIC-silicon is obtained using much lower process temperatures, compared to common high temperature processes, the process route presented becomes interesting for sensor applications on temperature sensitive substrates. [Copyright &y& Elsevier]

Abstract: The congener profile of samples contaminated with dioxin and dioxin-like compounds allows identifying sources of contamination. This article studies the statistical methods of congener profile analysis reported in the literature with respect to the reliability of obtained results. The performance of customary analysis methods regarding raw data transformation and applied TEF (toxic equivalency factor) values is discussed. In particular, the method of principal component analysis and k-means cluster is taken as an example and examined in detail. Reasons for occurring inconsistencies such as the dependence of results on raw data transformation and the disregard of measurement uncertainty are described, and it is shown that they also explain inconsistencies in other methods of cluster analysis such as hierarchical cluster analysis and neural networks. It is concluded that these methods cannot be employed to reach court-proof decisions, i.e. decisions which meet court evidentiary standards. An alternative approach to analyzing congener profiles based on mathematical statistics is briefly presented, allowing reliable, court-proof decisions. [Copyright &y& Elsevier]

Abstract: A novel Arxula adeninivorans yeast estrogen screen (nAES) assay has been developed for detection of estrogenic activity in various liquid samples such as wastewater, seawater, brackish water and swine urine. Two bio-components were engineered to co-express the human estrogen receptor α (hERα) and an inducible reporter gene; either the non-conventional phytase gene (phyK, derived from Klebsiella sp. ASR1) or the non-conventional tannase gene (ATAN1, derived from Arxula). Both reporters were put under the control of an Arxula derived glucoamylase (GAA) promoter, which was modified by the insertion of two estrogen-responsive elements (EREs). The Arxula transformation/expression platform Xplor® 2, which lacks resistance markers and E. coli elements, was used to select stable mitotic transformants. They were then analyzed for robustness and suitability as the bio-component for the nAES assay. Two types of the nAES assay based on the reporter proteins phytase and tannase (nAES-P, nAES-T) were used in this work. The nAES-P type is more suitable for the analysis of seawater, brackish water and urine whereas the nAES-T type exhibited higher robustness to NaCl. Both assay types have similar characteristics for the determination of estrogen in sewage and urine samples e.g. 6–25h assay period with detection and determination limits and EC50 values for 17β-estradiol of 2.8ngL−1, 5.9ngL−1, 33.2ngL−1 (nAES-P) and 3.1ngL−1, 6.7ngL−1 and 39.4ngL−1 (nAES-T). Substrate specificity and analytical measurement range (AMR) for both assay types are also similar. These characteristics show that the nAES assay based on non-conventional salt tolerant yeast is applicable for a high throughput estrogen analysis in the environmental and regulatory control sectors. [ABSTRACT FROM AUTHOR]

A flexible approach to producing optical interconnects on 609.6 * 609.6 mm large-area panels is demonstrated. Stepwise projection patterning from 101.6 * 101.6 mm masks has generated optical waveguide patterns over the whole panel using large-area projection lithography equipment. The wave-guide routing design allows optical waveguides on different 101.6 * 101.6 mm tiles to be interconnected. Four different waveguide connecting geometries in the border region between tiles have been fabricated and tested. Multimode waveguides from inorganic-organic hybrid polymers (ORMOCER) (cross section: ≤ 50 μm * 10 μm) with refractive index step between core and cladding Δn = 0.01 were produced. The index step was adjusted by mixing two diffrent ORMOCER systems. The materials show good adhesion to numerous substrates, such as glass and silicon. Application concepts such as flexible manufacturing of optoelectrical hybrid backplanes with two-dimensional interconnect, a three-dimensional optical interconnect with optical vias, and a hybrid backplane with the optical interconnect in a strip-format on a separate plane right above the electrical plane are proposed. Promising new technologies are presented along with preliminary demonstrativ viability. [ABSTRACT FROM AUTHOR]

Explores the potential of high-frequency produced microstrip lines, ring resonators, vias, stacked capacitors and filters as dielectric materials and processing technologies for microwave applications. Property profile of inorganic-organic hybrid materials for both dielectric and optical applications; Overview of the manufacturing of HF-test objects; Design, simulation and HF-characterization; Cost issues for manufactured devices.

For the one‐way random effects model three noniterative robust variance component estimators are investigated. For these estimators block breakdown points, measurement breakdown points and efficiency are derived. It is shown that the block breakdown points are approximating 50% and that the measurement breakdown points are not smaller than 25%. By deriving the asymptotic normal distribution of these estimators we show that two of the new estimators have an asymptotic efficiency greater than 82% and under certain circumstances up to 96%. Competing estimators have lower breakdown points and lower efficiencies. A simulation study shows that the high efficiency also appears for finite samples. The use of the estimators for interlaboratory tests is demonstrated in a practical example. [ABSTRACT FROM PUBLISHER]

Background: Severe coronavirus disease 2019 (COVID-19) disease courses are characterized by immuno-inflammatory, thrombotic, and parenchymal alterations. Prediction of individual COVID-19 disease courses to guide targeted prevention remains challenging. We hypothesized that a distinct serologic signature precedes surges of IL-6/D-dimers in severely affected COVID-19 patients. Methods: We performed longitudinal plasma profiling, including proteome, metabolome, and routine biochemistry, on seven seropositive, well-phenotyped patients with severe COVID-19 referred to the Intensive Care Unit at the German Heart Center. Patient characteristics were: 65 ± 8 years, 29% female, median CRP 285 ± 127 mg/dL, IL-6 367 ± 231 ng/L, D-dimers 7 ± 10 mg/L, and NT-proBNP 2616 ± 3465 ng/L. Results: Based on time-series analyses of patient sera, a prediction model employing feature selection and dimensionality reduction through least absolute shrinkage and selection operator (LASSO) revealed a number of candidate proteins preceding hyperinflammatory immune response (denoted ΔIL-6) and COVID-19 coagulopathy (denoted ΔD-dimers) by 24–48 h. These candidates are involved in biological pathways such as oxidative stress/inflammation (e.g., IL-1alpha, IL-13, MMP9, C-C motif chemokine 23), coagulation/thrombosis/immunoadhesion (e.g., P- and E-selectin), tissue repair (e.g., hepatocyte growth factor), and growth factor response/regulatory pathways (e.g., tyrosine-protein kinase receptor UFO and low-density lipoprotein receptor (LDLR)). The latter are host- or co-receptors that promote SARS-CoV-2 entry into cells in the absence of ACE2. Conclusions: Our novel prediction model identified biological and regulatory candidate networks preceding hyperinflammation and coagulopathy, with the most promising group being the proteins that explain changes in D-dimers. These biomarkers need validation. If causal, our work may help predict disease courses and guide personalized treatment for COVID-19. [ABSTRACT FROM AUTHOR]

In September 2013, the AACC International (AACI) Protein Technical Committee (now Protein and Enzymes Technical Committee) initiated a collaborative study of a method for the qualitative analysis of intact gluten in processed and nonprocessed corn products, using an R5 immunochromatographic dipstick system. It was validated to demonstrate that potential gluten-free products contain gluten lower than the Codex threshold of 20 mg/kg gluten. The results of the collaborative test with 18 participants confirmed that the method is suitable to detect gluten contaminations that are clearly lower than the threshold. It is recommended that the method be accepted by AOAC as Official First Action. [ABSTRACT FROM AUTHOR]

Background: Despite the significance of colonoscopy for early diagnosis of colorectal adenocarcinoma (CRC), population-wide screening remains challenging, mainly because of low acceptance rates. Herein, exosomal (exo-miR) and free circulating microRNA (c-miR) may be used as liquid biopsies in CRC to identify individuals at risk. Direct comparison of both compartments has shown inconclusive results, which is why we directly compared a panel of 10 microRNAs in this entity. Methods: Exo-miR and c-miR levels were measured using real-time quantitative PCR after isolation from serum specimens in a cohort of 69 patients. Furthermore, results were compared to established tumor markers CEA and CA 19-9. Results: Direct comparison of exo- and c-miR biopsy results showed significantly higher microRNA levels in the exosomal compartment (p < 0.001). Exo-Let7, exo-miR-16 and exo-miR-23 significantly differed between CRC and healthy controls (all p < 0.05), while no c-miR showed this potential. Sensitivity and specificity can be further enhanced using combinations of multiple exosomal miRNAs. Conclusions: Exosomal microRNA should be considered as a promising biomarker in CRC for future studies. Nonetheless, results may show interference with common comorbidities, which must be taken into account in future studies. [ABSTRACT FROM AUTHOR]

Abstract: The EstraMonitor has been developed to provide a device suitable for monitoring estrogens in sewage treatment plants, i.e. provide rapid detection in semi-online operation. This monitor is based on recombinant Arxula adeninivorans yeast cells as the biocomponent. The cells were engineered to co-express the human estrogen receptor α (hERα) gene and the inducible phytase (phyK, derived from Klebsiella sp. ASR1) reporter gene under the control of a promoter with estrogen response elements (EREs). The monitor comprises two measuring chambers containing immobilized transgenic yeast cells – a measuring strain with receptor and reporter gene cassettes and a control strain with only the reporter gene cassette. To measure the estrogenic activity, the measuring and control strains are incubated with the samples. In the presence of estrogenic substances, such as 17β estradiol (E2), the phyK gene is expressed and recombinant phytase is secreted into the sample. Any signal in the control strain is due to background activity and is used to correct the measuring strain signal. Phytase dephosphorylates p-aminophenyl phosphate (pAPP) and the level of phytase was quantified by electrochemically reducing the intermediate product, p-aminophenol (pAP). The electrons are detected as current and are proportional to the level of phytase activity. Since E2 concentration is correlated with phytase activity, the estrogenic activity can be calculated. The EstraMonitor can detect the total estrogenic activity in about 4h with a measurement range between 5 and 100ngL−1, and limit of detection of 5.3ngL−1. [Copyright &y& Elsevier]

The detection of food fraud and undeclared food allergens is one of the major challenges for competent authorities. Because adulterations are continuously adapted to the methods used to uncover them, the accomplishment of this task has become increasingly difficult over time. In recent years, various new promising methods for the detection of multiple food adulterants and multiple food allergens have been developed. Some of them utilize LC-MS to identify specific marker peptides. However, these methods have yet to be validated and standardized. For this reason, the German officials have established a working group with the objective of validating methods through multilaboratory validation studies. The experts of the working group also aim for the first time to standardize validated methods and to develop general validation criteria. This manuscript will highlight the current work of the group. For this purpose, an overview is given on the principles and applications of the new mass spectrometric methods. Moreover, requirements and the present work of other institutions regarding method validation are described. [ABSTRACT FROM AUTHOR]

Arxula adeninivorans -based yeast cell assays for the detection of steroid hormones demonstrated their efficiency for the determination of total hormone activity in a variety of samples using a microtiter plate format. In this study, a preliminary chromatographic separation using thin-layer chromatography plates is introduced in order to allow a rapid identification of the compounds responsible for this hormonal activity. The yeast whole cell assay can then be performed on the plate, producing a detectable signal where a steroid hormone is present. Simultaneous detection of estrogens, progestogens and androgens on the same plate in the picogram range was achieved, while keeping the assay as simple and affordable as possible. The assay requires a single incubation of the thin-layer chromatography plate and the detection of reporter protein production can be performed by fluorescence scanning of the plate at different wavelengths. The chromatographic separation allows the separation of several estrogens, androgens and progestogens, thus making its application for ‘real world’ samples very useful. In this work, different water-based samples from environmental origins were used to demonstrate the capacity of this new bioassay. Trials showed that most samples, with the exception of complex samples such as wastewater influent, can be assayed. [ABSTRACT FROM AUTHOR]

Background: This meta-analysis evaluated whether pretherapy serum levels of carcinoembryonic antigen (CEA) and cytokeratin-19 fragments (CYFRA 21-1) are predictive of response to therapy in non-small cell lung cancer (NSCLC) and whether changes in these markers during vs pretherapy are indicative of response.Methods: Original peer-reviewed studies enrolling adults with untreated advanced NSCLC were identified using PubMed. Two reviewers independently extracted data from eligible studies and assessed study heterogeneity and the risk of study bias.Results: Fourteen studies were eligible; 11 had objective response as an end point and three evaluated clinical benefit (i.e., response and stable disease). Study bias was relatively low. Both markers showed comparable modest predictive value across studies, with baseline CYFRA 21-1 numerically better in predicting treatment benefit. A good performance in identifying objective response during treatment was seen (AUC 0.724 (95% CI 0.667-0.785) for CYFRA 21-1 and 0.728 (95% CI, 0.599-0.871) for CEA). A decline in CYFRA 21-1 levels during treatment was highly indicative for objective response (sensitivity 79.1% (95% CI 71.5-85.1)).Conclusions: Comprehensive analysis of study heterogeneity and bias provides a high level of evidence for the clinical utility of CEA and CYFRA 21-1 for the prediction and monitoring of response in NSCLC. [ABSTRACT FROM AUTHOR]

The U.S. Food and Drug Administration (FDA) oversees a long-standing cooperative federal and state milk sanitation program that uses the grade "A" Pasteurized Milk Ordinance standards to maintain the safety of grade "A" milk sold in the United States. The Pasteurized Milk Ordinance requires that grade "A" milk samples be tested using validated total aerobic bacterial and coliform count methods. The objective of this project was to conduct an interlaboratory method validation study to compare performance of a film plate method with an automated most-probable-number method for total aerobic bacterial and coliform counts, using statistical approaches from international data standards. The matrix-specific validation study was administered concurrently with the FDA's annual milk proficiency test to compare method performance in five milk types. Eighteen analysts from nine laboratories analyzed test portions from 12 samples in triplicate. Statistics, including mean bias and matrix standard deviation, were calculated. Sample-specific bias of the alternative method for total aerobic count suggests that there are no large deviations within the population of samples considered. Based on analysis of 648 data points, mean bias of the alternative method across milk samples for total aerobic count was 0.013 log CFU/ml and the confidence interval for mean deviation was --0.066 to 0.009 log CFU/ml. These results indicate that the mean difference between the selected methods is small and not statistically significant. Matrix standard deviation was 0.077 log CFU/ml, showing that there is a low risk for large sample-specific bias based on milk matrix. Mean bias of the alternative method was -0.160 log CFU/ml for coliform count data The 95% confidence interval was --0.210 to --0.100 log CFU/ml, indicating that mean deviation is significantly different from zero. The standaid deviation of the sample-specific bias for coliform data was 0.033 log CFU/ml, indicating no significant effect of milk type. [ABSTRACT FROM AUTHOR]

The two Arxula adeninivorans -based bioassays (A-YGS and A-YGFS) described here provide sensitive and reliable screening for glucocorticoids in aquatic environments. The biocomponents of A-YGS and A-YGFS were constructed to carry the human glucocorticoid receptor ( hGRα ) and the phytase gene ( phyK , derived from Klebsiella sp. ASR1) or a fluorescence dsRED gene (derived from the Discosoma sp.), as reporter genes. The responses of A-YGS and A-YGFS were measured photometrically and spectrofluorometrically respectively. The half effective concentration (EC 50 ) and limit of detection (LoD) values for dexamethasone obtained with A-YGS and A-YGFS were 0.81 and 0.29 μM, and 9.42 and 0.47 μM, respectively. Furthermore, both bioassays exhibited different binding specificities for several natural and synthetic glucocorticoids: A-YGS – corticosterone > cyproterone acetate > mifepristone > dexamethasone > cortisol > methylprednisolone > prednisolone and A-YGFS – cortisol >corticosterone >dexamethasone >prednisolone >betamethasone >methylprednisolone. As proof of principle, A-YGS was used to assay total glucocorticoids in river water, wastewater influent and effluent taken from a wastewater treatment plant in Germany. Glucocorticoids were not detected in both A-YGS and LC–MS/MS in seven of the eight samples, however a dexamethasone equivalent (DEQ) was detected in an influent wastewater sample using A-YGS (0.055 μM), while LC–MS/MS analysis showed that hydrocortisone and cortisone were present at 0.063 and 0.083 nM, respectively. [ABSTRACT FROM AUTHOR]

This study describes the development of a bioassay to detect the presence of progesterone and progesterone-like molecules in wastewater samples. The basis of the bioassay is the integration of the human progesterone receptor gene into the yeast Arxula adeninivorans for the constitutive synthesis of the receptor. After incubation, binding of the analyte to the receptor induces the production of a reporter protein. Two reporter proteins were compared for detection parameters such as half-maximal activity (EC), limit of detection (LoD) and limit of quantification (LoQ). When the extracellular phytase K was used, an EC value of 155 ng L and a LoD of 27 ng L progesterone were obtained after 4 h incubation, while use of the fluorescent dsRED as the reporter protein, resulted in an EC of 320 ng L and a LoD of 65 ng L after 20 h incubation. Use of phytase K as the reporter protein offers decreased incubation time and increased sensitivity; however the dsRED reporter system is less labor-intensive. Additionally, the affinity of known agonists and antagonists of the human progesterone receptor was determined. The utility of this bioassay was confirmed by measuring total progesterone equivalent concentration of samples from a wastewater treatment plant. The A. adeninivorans-based transactivation assay was able to measure concentrations of about 311 ng L in the influent stream but could not detect progesterone activity in effluent. One key feature of the assay is the robustness of A. adeninivorans, which allows sample measurement without any sample preparation. [ABSTRACT FROM AUTHOR]

An Arxula adeninivorans based microbial biosensor has been developed for the determination of pharmaceuticals and chemicals such as omeprazole, lansoprazole, β-naphtoflavone and methylcholanthrene within 5 h using biochemical detection and 4 h and 10 min using amperometric detection. The biosensor consists of genetically modified A. adeninivorans G1212/YRC102-hAhR-hARNT-phyK ( hAhR – human arylhydrocarbon receptor; hARNT – human arylhydrocarbon receptor nuclear translocator; inducible phyK – derived from Klebsiella sp. ASR1) as the biological component and coupled with either a biochemical or an amperometric detection method. The combination between hAh receptor gene, hARNT and the A. adeninivorans -derived glucoseamylase promoter of the reporter gene ( GAA ) containing specific cyp1A1 -derived core sequence created a construct which enabled specific induction by pharmaceuticals. This offers a new cell-based biosensor for the pharmaceutical determination. The half maximum effective concentration (EC 50 ) and the limit of detection (LoD) were found to be 236.13, 95.01 and 174.72, 83.65 μg/l for omeprazole and lansoprazole, respectively. These two pharmaceuticals are among the most widely used internationally. Additionally A. adeninivorans G1212/YRC102-hAhR-hARNT-phyK cells allow the measurement in raw wastewater, i.e. not concentrated, unpurified and untreated which will allow on-site operation in sewage treatment plants. [ABSTRACT FROM AUTHOR]

For the first time, the full length recombinant HER-2[neu] receptor has been produced in a yeast ( Arxula adeninivorans ). It is one of the most studied membrane receptors in oncology and is involved in aggressive tumor formation. A yeast integration rDNA cassette containing the human gene coding for the HER-2[neu] protein was constructed and a screening procedure was performed to select the most productive transformant. Different detergents were tested for efficient solubilization of the membrane bound protein, with CHAPS giving the best results. To increase the yield of the recombinant protein from HER-2[neu] producing A. adeninivorans , optimal culture parameters were established for cultivation in bioreactor. The recombinant protein was subsequently assayed using ELISA and SPR immunoassays systems with antibodies raised against two different epitopes of the human receptor. In both cases, elution fractions containing the recombinant HER-2[neu] receptor successfully reacted with the immunoassays with limits of quantification below 100 ng ml −1 . These results demonstrate that the full length recombinant HER-2[neu] reported here has the potential to be a new standard for the detection of HER-2 type cancer. [ABSTRACT FROM AUTHOR]

The novel A-YAS assay for the detection of androgenic activity in liquid samples such as urine has been developed and assessed. The assay is based on transgenic Arxula adeninivorans yeast cells as the bio-component. The cells were engineered to co-express the human androgen receptor ( hAR ) gene and the inducible phytase reporter gene ( phyK , derived from Klebsiella sp. ASR1 ), under the control of an Arxula derived glucoamylase ( GAA ) promoter, which had been modified by the insertion of hormone-responsive elements (HREs). The Arxula transformation/expression platform Xplor®2 was used to select stable mitotic resistance marker free transformants and the most suitable cells were characterized for performance as a sensor bio-component. The assay is easy-to-use, fast (6–25 h) and is currently the most sensitive yeast-based androgen screen with an EC 50 , limit of detection and of quantification values for 5 α -dihydrotestosterone (DHT) of 277.1 ± 53.0, 56.5 ± 4.1 and 76.5 ± 6.7 ng L − 1 , respectively. Furthermore, the assay allows the determination of androgenic and anti-androgenic activity of various compounds such as naturally occurring androgens and estrogens, pharmaceuticals and biocides. The robustness of the A-YAS assay enables it to be used for analysis of complex samples such as urine. The results of the analysis of a number of cattle urine samples achieved by the A-YAS assay correlate well with GC-MS analysis of the same samples. [ABSTRACT FROM AUTHOR]

A proficiency test (PT) program for determination of total As in apple juice samples was conducted by the Food Emergency Response Network (FERN) laboratories. An analytical method using inductively coupled plasma (ICP)-MS was validated for this project. The LOD and LOQ were determined to be 0.315 and 2.32 ng/g, respectively. A total of eight apple juice samples were sent to 38 FERN laboratories, and results were statistically evaluated according to ISO 13528:2005. The total As concentrations in the PT samples reported by the participating laboratories were very close to those obtained in the homogeneity and stability tests. The reproducibility, repeatability, interlaboratory, and intralaboratory variability results led to 69% of participating laboratories being rated as satisfactory using the widely accepted |z| score ≤2 criterion. The percentage of laboratories with acceptable z scores (|z| scores ≤2) increased from 61 to 89% with the increase in As concentration in PT samples from 5.05 to 30.72 ng/g. This study demonstrated that the ICP/MS method was adequate for total As determination in fruit juice, and most of the participating laboratories were proficient in their analytical performance. [ABSTRACT FROM AUTHOR]

Abstract: The ‘EstraMonitor’ was developed to provide an automated system for the detection of estrogenic compounds. It can be used for semi-online and continuous monitoring without additional instrumentation. Previously it was used to detect pure estrogenic molecules. In this investigation, the ‘EstraMonitor’ is used to detect the estrogenic activity in five non-pretreated wastewater samples. The ‘EstraMonitor’ employs genetically modified Arxula adeninivorans G1212/YRC102-hERα-phyK yeast cells as the detection component. Both immobilized and non-immobilized A. adeninivorans G1212/YRC102-hERα-phyK cells remained fully functional in a wide range of samples, including samples that contained up to 5% NaCl. The results demonstrate that it is possible to determine the estrogenic effects in environmental samples without the need for sterilization, extraction or concentration. The 17β-estradiol equivalent quotient (bio-EEQ) values in these samples were measured by both biochemical and amperometric methods and were compared to GC–MS analyses (ana-EEQ). The three methods showed a good correlation over a similar detection range. [Copyright &y& Elsevier]

European interlaboratory collaborative study was conducted to validate a method for the quantitative determination of lipophilic marine biotoxins based on high-performance liquid chromatography-tandem mass spectrometry. During this study, the diarrhetic shellfish poisoning toxins okadaic acid, dinophysis toxin1 and 2 including their esters, the azaspiracids 1-3, pectenotoxin2, and the yessotoxins were investigated at concentration levels near the limit of quantification and near the legal limit. Naturally contaminated blue mussels, both raw and cooked and spiked extracts of clams and oysters were studied and results were obtained for 16 test samples from 16 laboratories representing eight different countries. This article summarizes the study outcome concerning validation key parameters like specificity, linearity, limit of detection, accuracy/recovery, and precision. Further, influences of cooking of mussels before homogenization or hydrolysis on method robustness have been evaluated. [ABSTRACT FROM AUTHOR]

Adverse effects of drug combinations and their underlying mechanisms are highly relevant for safety evaluation, but often not fully studied. Hydroxychloroquine (HCQ) and azithromycin (AZM) were used as a combination therapy in the treatment of COVID-19 patients at the beginning of the pandemic, leading to higher complication rates in comparison to respective monotherapies. Here, we used human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) to systematically investigate the effects of HCQ, AZM, and their combination on the structure and functionality of cardiomyocytes, and to better understand the underlying mechanisms. Our results demonstrate synergistic adverse effects of AZM and HCQ on electrophysiological and contractile function of iPSC-CMs. HCQ-induced prolongation of field potential duration (FPDc) was gradually increased during 7-day treatment period and was strongly enhanced by combination with AZM, although AZM alone slightly shortened FPDc in iPSC-CMs. Combined treatment with AZM and HCQ leads to higher cardiotoxicity, more severe structural disarrangement, more pronounced contractile dysfunctions, and more elevated conduction velocity, compared to respective monotreatments. Mechanistic insights underlying the synergistic effects of AZM and HCQ on iPSC-CM functionality are provided based on increased cellular accumulation of HCQ and AZM as well as increased Cx43- and Nav1.5-protein levels. [ABSTRACT FROM AUTHOR]

Within the framework of the ENFSI Expert Working Group “Firearms” a proficiency test on the detection and identification of GSR by energy-dispersive scanning electron microanalysis (SEM/EDX) is carried out in a 2 years term. The latest test was performed in 2005/2006 and was denoted as GSR2005. Seventy-five laboratories from 28 countries participated in this proficiency test and submitted in total 83 independent data-sets. The participating laboratories were requested to determine the total number of PbSbBa containing particles on a synthetic test sample following their own laboratory specific methods of automated GSR particle search and detection by SEM/EDX. Furthermore size and position of the detected particles had to be reported by the laboratories and were evaluated statistically. The results were compiled by means of z-scores according to the IUPAC and EURACHEM guidelines—assessing individual laboratory achievements (inter-laboratory) as well as intra-laboratory performance—and were compared to the results of the previous proficiency test run GSR2003 ( 1 ). The comparison shows that there is a noticeable improvement in the method’s detection capability. [ABSTRACT FROM AUTHOR]

Abstract: A novel yeast cell-based assay was developed for the detection of estrogenic activity in wastewater. Recombinant Arxula adeninivorans strains were engineered to co-express the human estrogen receptor α (hERα) and a Klebsiella-derived phytase (phyK) reporter gene under the control of an A. adeninivorans-derived glucoamylase (GAA) promoter which had been modified by the insertion of estrogen-responsive elements (EREs). In the presence of estrogenic compounds, hERα dimerizes and binds to the estrogen. Reporter gene expression is induced by subsequent binding of the hERα-dimer/estrogen complex to estrogen responsive elements (ERE) in the promoter. The insertion of different numbers of EREs in three alternative promoter positions and its effect on reporter gene expression were assessed. In one of the constructs, a detection limit of 5ngl−1 and a determination limit of 10ngl−1 for 17β-estradiol-like activity was achieved. The photometric assay used enabled estrogen determination in sewage samples within 30h. [Copyright &y& Elsevier]

Summarizes results of a proficiency test on the detection and identification of gunshot residues by scanning electron microcopy and energy dispersive X-ray micro-analysis in the United States. Improvements in the proficiency test; Performance of the participating laboratories; Statistical evaluation; Comparison of results with previous studies.

In the course of this study 37 sediment samples were analyzed. They were taken after the flooding in September 2002 along the Elbe and at the mouths of its major tributaries. The sampling program covered the entire river stretch that was affected by the floods, from Obristvi (Czech Republic) to the Elbe estuary (North Sea) on the German coast. Analyses were performed for dioxins, nonylphenols, nonylphenol ethoxylates, bisphenol A, DEHP, musk fragrances, polybrominated diphenylethers, chloroalkylphosphates, organochlorine compounds, PAH, and organotin compounds. The results show that only a few weeks after the flood, contaminant concentrations in solid matter were comparable to those prevailing beforehand. Significant sources of contaminant input proved to be the tributaries Vltava (Moldau), Bilina (both in the Czech Republic), and the Mulde (Germany), as well as industrial and municipal sewage treatment works (STW) located along the Elbe. Further point sources are to be found in still water zones such as harbors and abandoned channels. These sources are activated when erosive action stirs up older sediments. Statistical analyses of the congener distribution of the dioxins provided evidence on the sources of these contaminants and freight levels in different river sections. The chemical analyses were complemented by results of ecotoxicological investigations with two sediment organisms ( Chironomus riparius and Potamopyrgus antipodarum ). [ABSTRACT FROM AUTHOR]

Data collected from FDA proficiency tests (PT) during 2012–2018 was used to evaluate the performance of most probable number (MPN) and polymerase chain reaction (PCR) methods used to enumerate Vibrio parahaemolyticus in oyster samples. The primary aim was to establish whether the MPN and PCR methods can be considered equivalent. The following criterion for equivalence was applied: the absolute value of mean bias and between-sample standard deviation must both be less than 0.1 (log10). Final calculations showed mean bias and between-sample standard deviation (SD) were 0.031 and 0.117 (log10) respectively. The between-sample SD criterion was slightly relaxed because with close to 700 results, the data set was large and overall mean bias was low. It was concluded that the two methods can be considered equivalent. The use of PT data for the assessment of method rather than laboratory performance is a secondary topic addressed in this paper. Important requirements for this use of PT data include availability of sufficient results for both methods and use of real food matrices. Ultimately, the results presented here provide an example of how PT data can be used to monitor method performance across many laboratories and samples as well as to assess method equivalence. • MPN and PCR Vibrio parahaemolyticus enumeration methods were compared. • Data was compiled from 7 years of shellfish proficiency testing in oyster samples. • Mean bias and between-sample standard deviation were used to evaluate equivalency. • V. parahaemolyticus MPN and PCR enumeration methods can be considered equivalent. • Results show proficiency testing data can be used to assess method performance. [ABSTRACT FROM AUTHOR]