Follow-up of the Bacillus cereus emetic toxin production in penne pasta under household conditions using liquid chromatography coupled with mass spectrometry

Two outbreak-related Bacillus cereus emetic strains were investigated for their growth and cereulide production potential in penne pasta at 4, 8 and 25 °C during 7-day storage. Cereulide production was detected and quantified by LC-MS method (LOD of 1 ng/ml, LOQ of 5 ng/ml) and growth was determined by culture-based enumeration. Inoculated B. cereus strains (10(5) CFU/g) were able to reach counts of more than 10(8) CFU/g and cereulide production of about 500 ng/g already after 3 days of storage at 25 °C. Interestingly, a constant increase of the toxin was noticed during incubation at ambient temperature storage: the cereulide was continuously produced during the bacterial stationary growth phase reaching maximal amounts at the end of the experiment (7 days, concentration of about 1000 ng/g). Strictly respected cold chain temperature as 4 °C did not allow any detectable cereulide production for any of the two tested strains. At the limited temperature abuse of 8 °C, a detectable amount of cereulide was observed after two days for one of the strain (TIAC303) (相似文献   

Galectins in Early Pregnancy and Pregnancy-Associated Pathologies

Galectins are a family of conserved soluble proteins defined by an affinity for β-galactoside structures present on various glycoconjugates. Over the past few decades, galectins have been recognized as important factors for successful implantation and maintenance of pregnancy. An increasing number of studies have demonstrated their involvement in trophoblast cell function and placental development. In addition, several lines of evidence suggest their important roles in feto-maternal immune tolerance regulation and angiogenesis. Changed or dysregulated galectin expression is also described in pregnancy-related disorders. Although the data regarding galectins’ clinical relevance are still at an early stage, evidence suggests that some galectin family members are promising candidates for better understanding pregnancy-related pathologies, as well as predicting biomarkers. In this review, we aim to summarize current knowledge of galectins in early pregnancy as well as in pregnancy-related pathologies.     

Genome-Wide Association Analysis and Genomic Prediction of Thyroglobulin Plasma Levels

Thyroglobulin (Tg) is an iodoglycoprotein produced by thyroid follicular cells which acts as an essential substrate for thyroid hormone synthesis. To date, only one genome-wide association study (GWAS) of plasma Tg levels has been performed by our research group. Utilizing recent advancements in computation and modeling, we apply a Bayesian approach to the probabilistic inference of the genetic architecture of Tg. We fitted a Bayesian sparse linear mixed model (BSLMM) and a frequentist linear mixed model (LMM) of 7,289,083 variants in 1096 healthy European-ancestry participants of the Croatian Biobank. Meta-analysis with two independent cohorts (total n = 2109) identified 83 genome-wide significant single nucleotide polymorphisms (SNPs) within the ST6GAL1 gene (p<5×10−8). BSLMM revealed additional association signals on chromosomes 1, 8, 10, and 14. For ST6GAL1 and the newly uncovered genes, we provide physiological and pathophysiological explanations of how their expression could be associated with variations in plasma Tg levels. We found that the SNP-heritability of Tg is 17% and that 52% of this variation is due to a small number of 16 variants that have a major effect on Tg levels. Our results suggest that the genetic architecture of plasma Tg is not polygenic, but influenced by a few genes with major effects.     

Me-DLC films as material for highly sensitive temperature compensated strain gauges

In technical applications strain gauges are widely used. Apart from conventional polymer foil based strain gauges that are glued to the work piece surface, sputtered strain gauges are already commercially used in special applications. Those sputter strain gauges are typically made of NiCr alloy and the sensor layer is as sensitive to strain as the ones used in the glued strain gauges with a gauge factor of 2, but neglecting problems of creeping and swelling of the involved polymer materials. Diamond-like carbon (DLC) films offer significantly higher strain sensitivity, but usually they are also very sensitive to temperature effects. Using metal doped diamond-like carbon (Me-DLC), higher strain sensitivity than conventional metal based systems, in combination with thermal compensation, is possible. The influence of different process parameters on the gauge factor and temperature coefficient of resistance (TCR) of DLC and Me-DLC films produced in industrial sputtering systems was investigated. Gauge factors up to 13 in combination with a high negative TCR in the range of a few thousand ppm/K were reached with sputtered DLC films. The substrate bias voltage in particular showed a strong influence on the resulting gauge factor of the films. For Me-DLC films different deposition methods (dc and rf sputtering) and various doping metals (Ag, Ni, Ti, and W) were investigated. Using dc sputtering of the Me-DLC films only Ni-DLC showed gauge factors slightly higher than 2. Furthermore, only for Ni-DLC zero crossing of the TCR was observed by variation of the metal content. Using rf excitation especially Ni-DLC films showed gauge factors exceeding values of 15 in combination with a TCR close to zero.     

The comparative study of biocomposites based on hydrochar and chitosan-modified urea-formaldehyde resins

To provide new insight into the field of urea-formaldehyde (UF) adhesives science, in this work, for the first time, UF resin was modified with hydrochar of spent mushroom substrate (HCUF) and chitosan (CHUF) to investigate the effect of these bio-fillers on the hydrolytic and thermal stability of in situ prepared UF resins. The characterization of the modified UF biocomposites was performed using X-ray diffraction analysis (XRD), Fourier transforms infrared spectroscopy (FTIR), non-isothermal thermogravimetric analysis (TG), differential thermal gravimetry (DTG), and differential thermal analysis (DTA). Scanning electron micrographs (SEM) of the CHUF and HCUF biocomposites show a spherical structure that differs from each other because the surface of the CHUF biocomposite has pronounced pores that form a network structure. With its hydroxyl and amino groups, chitosan bonding to UF resin through hydrogen bonds, which is confirmed by FTIR analysis. The content of free FA in CHUF biocomposite is 0.06%, while that of HCUF is higher and amounts to 0.48%. The content of released FA in both modified UF biocomposites was similar (2.5% and 2.8% for CHUF and HCUF, respectively). The hydrolytic stability of CHUF is slightly higher compared to the HCUF biocomposite. Thermal analysis shows that the CHUF is thermally more stable because it starts to decompose at a slightly higher temperature than the HCUF biocomposite.     

Thermodynamic modeling of vapor-liquid equilibria and excess properties of the binary systems containing diethers and n-alkanes by cubic equation of state

A comparison of the performances of two different approaches of cubic equations of state models, based on a classical van der Waals and mixing rules incorporating theG ^E equation, was carried out for correlation of Vapor-Liquid Equilibria (VLE), H^E and C _P ^E data alone, and simultaneous correlation of VLE+H^E, VLE+C _P ^E , H^E +C _P ^E and VLE+H^E +C _P ^E data for the diethers (1,4-dioxane or 1,3-dioxolane) with n-alkane systems. For all calculations the Peng-Robinson-Stryjek-Vera cubic equation of state (PRSV CEOS) was used. A family of mixing rules for the PRSV CEOS based on the Modified van der Waals one-fluid mixing rule (MvdW1) and two well-known CEOS/G^E mixing rules (MHV1 and MHV2), was considered. The NRTL equation, as the G^E model with linear or reciprocal temperature dependent parameters, was incorporated in the CEOS/G^E models. The results obtained by the CEOS/G^E models exhibit significant improvement in comparison to the MvdW1 models.     

Deposition of silver ions onto DBD and DCSBD plasma treated nonwoven polypropylene

The aim of this work is plasma activation of nonwoven polypropylene (PP) using two different ambient air plasma sources: volume dielectric barrier discharge (DBD) and diffuse coplanar surface barrier discharge (DCSBD) and its functionalization by silver ion deposition.     

Total and individual carotenoids and phenolic acids content in fresh,refrigerated and processed spinach (Spinacia oleracea L.)

The carotenoid and phenolic acid contents in fresh, stored and processed (blanched, frozen and boiled) spinach were comparatively determined by spectrophotometric and HPLC analyses. The major carotenoids identified after HPLC analysis in saponified samples were lutein (37–53 μg/kg), β-carotene (18–31 μg/kg), violaxanthin (9–23 μg/kg) and neoxanthin (10–22 μg/kg). These carotenoids were all affected by storage and/or heating. The content of carotenoids was best preserved after storage for one day at 4 °C.