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The traditional fermentation process of soy sauce employs a hyperhaline model and has a long fermentation period. A hyperhaline model can improve fermentation speed, but easily leads to the contamination of miscellaneous bacteria and fermentation failure. In this study, after the conventional koji and moromi fermentation, the fermentation broth was pasteurized and diluted, and then inoculated with three selected microorganisms including Corynebacterium glutamicum, Corynebacterium ammoniagenes, and Lactiplantibacillus plantarum for secondary fermentation. During this ten-day fermentation, the pH, free amino acids, organic acids, nucleotide acids, fatty acids, and volatile compounds were analyzed. The fermentation group inoculated with C. glutamicum accumulated the high content of amino acid nitrogen of 0.92 g/100 mL and glutamic acid of 509.4 mg/100 mL. The C. ammoniagenes group and L. plantarum group were rich in nucleotide and organic acid, respectively. The fermentation group inoculated with three microorganisms exhibited the best sensory attributes, showing the potential to develop a suitable fermentation method. The brewing speed of the proposed process in this study was faster than that of the traditional method, and the umami substances could be significantly accumulated in this low-salt fermented model (7% w/v NaCl). This study provides a reference for the low-salt and rapid fermentation of seasoning. [ABSTRACT FROM AUTHOR]

The vapor‐phase nitrilation of dimethyl adipate (DMA) with ammonia (NH3) is an environmentally benign route leading to adiponitrile (ADN) with great application value. In this study, the performance of HZSM‐5 zeolites, widely used in industry as the solid acid catalysts, was investigated. It exhibits a strong correlation between the SiO2/Al2O3 ratio (SAR) in HZSM‐5 zeolites and the reactivity (both activity and selectivity). The influence of Al density closely related to the value of SAR on the reactivity of HZSM‐5 was thus elucidated by mechanistic experiments. As a result, the introduction of Al element to the framework is beneficial to the activation of ester functionality, thus improving the activity, especially at a high liquid hourly space velocity (LHSV). However, a high Al density will lead to poor selectivity and deactivation due to too strong adsorption of esters and intermediates (e. g., amides). Herein, the balanced adsorption/desorption capability was reached on HZSM‐5 with SAR as 631 (i. e., HZSM‐5‐631), which provides the best selectivity to nitriles (SADN+MCP, 92.5 %) at a high single‐pass conversion of DMA (CDMA, 98.0 %). [ABSTRACT FROM AUTHOR]

Aims: Apatinib is widely used in Chinese cancer patients. As the in vivo drug disposition of apatinib has large individual differences, adverse events are prone to occur. Cytochrome P450 (CYP)3A5 and cancer types maybe the main factors affecting this individual differences. The objective of our study was to establish a population pharmacokinetics (PK) model of apatinib in adult cancer patients, and to explore optimal dosage regimens for individualized treatment. Methods: Adult patients with various types of cancer treated with apatinib were enrolled. The concentration of apatinib in plasma was determined by high‐performance liquid chromatography–tandem mass spectrometry. CYP3A5 genotype was determined using TaqMan allelic discrimination technique. The population PK model was developed by NONMEM V7.4. The dosing regimen was optimized based on Monte Carlo simulations. Results: A population PK model of apatinib in adult cancer patient was established. CYP3A5 genotype and systemic cancer type (digestive system cancers, nondigestive system cancers) were the most significant covariates for PK parameters. Patients with CYP3A5*1 expressers (CYP3A5*1/*1 and CYP3A5*1/*3) had lower apparent clearance and apparent volume of distribution than patients who do not express CYP3A5*1 (CYP3A5*3/*3). Patients with nondigestive system cancer had higher apparent volume of distribution and absorption rate constant than digestive system cancer. The results of dose simulation suggest that the apatinib dose in patients who do not express CYP3A5*1 should be 33.33–50.00% higher than that in CYP3A5*1 expressers. Conclusions: A population PK model of apatinib in adult cancer patients was established. CYP3A5 genotype and systemic cancer type had concurrent effects on PK parameters. CYP3A5 patients who do not express CYP3A5*1 required higher doses. [ABSTRACT FROM AUTHOR]

For typical biodegradable polymers, their overall performance almost declines exponentially to the degradation degree, which inevitably leads to a dilemma between the requirements of service life and retention time in the environment (both in vitro and in vivo). It is a great challenge to develop a biodegradable polymeric device with relatively stable performance in service while rapidly degrading out of service. Herein, we demonstrate an effective strategy to control degradation of biodegradable polymers in stages by constructing separated bicontinuous microphases with very different microphase degradation rates. First, polyurethane copolymers (PCL-b-CrP-U) containing two blocks, i.e., semicrystalline poly(ε-caprolactone) (PCL) blocks and amorphous random copolymer blocks (CrP) based on ε-CL and p-dioxanone (PDO), were synthesized. The microscopic morphology of PCL-b-CrP-U is investigated by an alkali-accelerated degradation experiment, which also demonstrates that the chain cleavage-induced crystallization during degradation resulted in a self-reinforcement by forming degradation residues with a scaffold-like morphology. The tensile test shows that PCL-b-CrP-U has excellent mechanical properties (1500% of elongation at break, a tensile strength of about 7.5 MPa, and an elastic modulus of 40.0 MPa). The degradation experiments with artificial pancreatic juice as a working medium reveal that PCL-b-CrP-U samples containing relatively high PDO units exhibit a three-stage degradation, i.e. an induction stage, a steady degradation stage and an accelerated degradation stage. The CrP phase preferentially hydrolyzes to form some microchannels due to its amorphous nature and relatively high hydrophilicity, effectively accelerating the entry of water and enzymes into the inner parts of the sample. Meanwhile, at this stage, those originally amorphous PCL segments gradually crystalize owing to their enhanced chain mobility induced by the chain cleavage, forming a "scaffold"-like structure, which effectively reinforces the sample to resist the damage from external force and therefore guarantees a relatively stable mechanical performance of PCL-b-CrP-U during service. With the further depletion of the CrP phase, the intermediate "scaffold"-like structure is also very beneficial to accelerate the degradation of residues owing to its large specific surface area, which is expected to be beneficial for preventing long-term retention of the implantation devices. [ABSTRACT FROM AUTHOR]

In this study, palladium‐based heterogeneous catalysts were successfully prepared by encapsulating the palladium diphosphine complexes into an imine‐linked 2D‐COF (TPB‐DMTP‐COF) through a one pot self‐assembly approach. It not only prevents the oxidation of phosphine‐based ligand during the stepwise impregnation but also suppresses the coordination of imine linkers at the COF host to the palladium guest, thus enabling highly efficient encapsulation of the active bidentate phosphine chelated palladium complex by the widely explored imine‐linked COF. Besides, the dosage of diphosphine ligand (Xantphos‐SO3H, L) and the ratio of palladium to L in the preparation of [Pd]@COF hybrids can be readily adjusted under such one pot procedure to satisfy the requirement of crystallinity, porosity, active sites, and CO adsorption capacity for the catalytic performance in the methoxycarbonylation of olefins. The resultant [Pd]@COF‐A‐0.25‐0.5 provides satisfied catalytic performance for both aliphatic and aromatic olefins with total esters up to 92.1 % under optimized conditions. These findings provide the basis for a novel design concept to design heterogeneous catalysts with high efficiency for reaction processes comprising the alkoxycarbonylation of olefins. [ABSTRACT FROM AUTHOR]

A new simple magnetic electrospinning setup was devised to manufacture partially aligned nanofiber in the paper. Compared with the traditional electrospinning setup, a U-shaped permanent magnet was employed and applied with a slide rheostat. Polyvinyl alcohol (PVA) and PVA/Fe3O4fibers were prepared by the magnetic electrospinning, respectively. The morphology and alignment of the fibers were characterized by the use of scanning electron microscopy (SEM). Results showed that the magnetic field could decrease the diameter of fibers and enhance the crystal conditions of fibers, and the addition of Fe3O4nanoparticles improved the alignment of nanofibers. [ABSTRACT FROM AUTHOR]

Shigellosis in chickens was first reported in 2004. This study aimed to determine the pathogenicity of Shigella in chickens and the possibility of cross-infection between humans and chickens. The pathogenicity of Shigella in chickens was examined via infection of three-day-old SPF chickens with Shigella strain ZD02 isolated from a human patient. The virulence and invasiveness were examined by infection of the chicken intestines and primary chicken intestinal epithelial cells. The results showed Shigella can cause death via intraperitoneal injection in SPF chickens, but only induce depression via crop injection. Immunohistochemistry and transmission electron microscopy revealed the Shigella can invade the intestinal epithelia. Immunohistochemistry of the primary chicken intestinal epithelial cells infected with Shigella showed the bacteria were internalized into the epithelial cells. Electron microscopy also confirmed that Shigella invaded primary chicken intestinal epithelia and was encapsulated by phagosome-like membranes. Our data demonstrate that Shigella can invade primary chicken intestinal epithelial cells in vitro and chicken intestinal mucosa in vivo, resulting in pathogenicity and even death. The findings suggest Shigella isolated from human or chicken share similar pathogenicity as well as the possibility of human-poultry cross-infection, which is of public health significance. [ABSTRACT FROM AUTHOR]

Contamination of organohalogen pollutants (OHPs), including dichlorodiphenyl trichloroethane and its metabolites (DDTs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), decabromodiphenylethane (DBDPE), hexabromocyclododecanes (HBCDs), and dechlorane plus (DP) in three metropolises of China, Beijing, Wuhan, and Guangzhou, and a reference rural site were determined using terrestrial residential passerine species as bioindicator. DDTs dominated in Wuhan whereas flame retardants dominated in Guangzhou and Beijing. No geographical variation was found for PCB levels but it exhibited different homologue profiles among different sites which could be attributed to different dietary sources of birds. Industry characteristics of the sampling location contributed to the geographical differences in the occurrence and contamination profile of OHPs. The transformation of traditional agriculture characterized contamination profiles to industry characterized profiles in Beijing and Guangzhou implicates significantly environmental concern on the flame retardants contamination in non-hot-spot regions of China. [Copyright &y& Elsevier]

The article focuses on the study of the development of an indirect test which uses antibodies and color change enzyme-linked immunosorbent assay (ELISA) to detect anti-porcine epidemic diarrhea virus (PEDV) antibody. Topics discussed include the cloning, sequencing, and, analysis of complete PEDV N gene, the immunoreaction activity of recombinant protein, and the results which shows that ELISA indicates a sensitive, specific, and reproducible results suitable for monitoring anti-PEDV antibody.

The article presents a study on the temporal and spatial expression characteristics of β1 gene in chicken intestine. The study used real-time fluorescence quantitative polymerase chain reaction (PCR) to establish a method of detecting the level of β1 expression. The results revealed the existence of β1 gene in chicken intestine and that the expression levels of β1 gene messenger RNA vary in different day-old chicken intestinal tissue.

The laboratory trophic transfer of hexabromocyclododecanes (HBCDs) was studied using predatory (oscar) fish and a prey species (tiger barb) exposed to a technical HBCD. Gut absorption, dynamic changes of diastereomer pattern and enantiomer fractions, and potential metabolism of HBCDs were examined. Compared with β- or γ-HBCD, α-HBCD showed lower absorption efficiency in the gut of oscar fish. A predominance of γ-HBCD was observed in the tiger barb after 5 d HBCD-exposed and oscar feeding on the tiger barb for 16 d. After 20 d of depuration, 41.1% γ-HBCD and 42.7% β-HBCD disappeared, and α-HBCD exceeded the initial amount. The transformation from γ-HBCD predominance in the food to α-HBCD predominance in the oscar was attributed mainly to the isomerization of γ-HBCD (at least 3% and up to 22.7%) to α-HBCD. Selective enrichment of the (+) α- and (−) β-enantiomers and no enantioselective enrichment of γ-HBCD were observed in the tiger barbs. No enantioselective uptake of the 3 diasteromers was found in the oscar gut. The enantiomer fractions of α- and γ-diastereomers were significantly higher, but that of β-diastereomer were significantly lower in the oscars than in the tiger barbs, indicating enantioselective metabolism of the 3 diastereomers. Two HBCD monohydroxylated metabolites were detected in the 2 fish species, but their composition patterns differed, indicating a species-specific metabolism of HBCD in the studied fish species. Environ Toxicol Chem 2013;32:2565-2570. © 2013 SETAC [ABSTRACT FROM AUTHOR]