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Aluminate is generally used as a flocculant in water and wastewater treatment processes, but the residual aluminum (Al) may have toxic effects on aquatic organisms when the concentration accumulates beyond a threshold level. The in situ and laboratory tests were conducted to evaluate the impact of residual Al on submerged macrophytes in West Lake, Hangzhou, China, which receives Al flocculant-purified water diverted from the Qiantang River. The responses of Vallisneria natans and Hydrilla verticillata were investigated based on their morphological and physiological parameters in pot culture and aquarium simulation experiments. In the pot culture experiments, the biomass, seedling number, plant height, stolon number, stolon length, and root weight were significantly higher at a site located 150 m from the inlet compared with those at a site located 15 m from the inlet ( P < 0.05), thereby indicating that the residual Al significantly inhibited the morphological development of V. natans and H. verticillata . The variations in the chlorophyll-a, protein, and malondialdehyde contents of the two species in both the pot culture and aquarium simulation experiments also demonstrated that the two submerged macrophytes were stressed by residual Al. V. natans and H. verticillata accumulated 0.052–0.227 mg of Al per gram of plant biomass (fresh weight, mg/g FW) and 0.045–0.205 mg Al/g FW in the in situ experiments, respectively, where the amounts of Al were significantly higher in the plants in the treatment aquaria during the laboratory experiments than those in the controls. These results may have important implications for the restoration of submerged macrophytes and ecological risk assessments in Al-exposed lakes. It is recommended that the Al salt concentration used for the control of lake eutrophication should be reduced to an appropriate level. [ABSTRACT FROM AUTHOR]

Abstract: Background: Laryngeal exposure to cigarette smoke (CS) evokes sensory irritation, but the mechanisms are largely unclear. The TRPA1 and TRPV1 receptors are two types of Ca2+-permeant channels located at the terminals of airway capsaicin-sensitive afferents. We investigated the mechanisms underlying the airway reflex evoked by laryngeal CS exposure in anesthetized rats. Methods: CS (7 ml) was delivered into a functionally isolated larynx, while the animals (n = 201) breathed spontaneously. Respiratory parameters were measured. All use of pharmacological agents involved pretreatment by laryngeal application. Results: Laryngeal CS exposure immediately evoked a concentration-dependant apneic response that was unrelated to the nicotine content of the CS. This inhibition of breathing was abolished by bilateral sectioning of the superior laryngeal nerves (SLNs) or by perineural capsaicin treatment of the SLNs (selective blocking of capsaicin-sensitive afferent neural conduction), suggesting the involvement of superior laryngeal capsaicin-sensitive afferents in the reflex. The reflex apnea was significantly attenuated by N-acetyl-l-cysteine (antioxidant), EGTA (extracellular Ca2+ chelator) and BAPTA-AM (intracellular Ca2+ chelator), indicating the importance of reactive oxygen species (ROS) and Ca2+. This reflex apnea was also partially reduced by HC030031 (TRPA1 receptor antagonist) and capsazepine (TRPV1 receptor antagonist), and was nearly abolished by a combination of these two antagonists, suggesting a central role for the TRPA1 and TRPV1 receptors. Furthermore, the reflex apnea was attenuated by indomethacin (cyclooxygenase inhibitor); however, the attenuation by indomethacin was not increased by pretreatment with HC030031 or capsazepine, indicating that TRPA1 and TRPV1 receptor functionality is, at least in part, linked to cyclooxygenase metabolites. Conclusions: The reflex apnea evoked by laryngeal CS requires activation of both TRPA1 and TRPV1 receptors, which are likely to be located at the terminals of superior laryngeal capsaicin-sensitive afferents. Laryngeal sensory irritation by CS seems to depend on the actions of ROS and cyclooxygenase metabolites on these two types of receptors. [Copyright &y& Elsevier]

Cascade charge transfer pathway elaborately designed over multilayered heterostructure accelerates interfacial charge transfer/separation towards multifarious photoredox catalysis. [Display omitted] • Interface-tunable heterostructured photocatalysts can effectively mediate charge transport kinetics and pathway. • All TMCs-comprising ternary heterostructures were fabricated by a progressive step-by-step cation exchange strategy. • Directional carrier transfer channel can be constructed over TMCs-based heterojunctions. • Spatially multilayered all TMCs-comprising heterostructure favors boosted multifarious photocatalysis. Maneuvering spatial photo-induced charge modulation/separation over semiconductor-based photocatalysts represents an enduring challenge in solar-powered photoredox catalysis, but suffers from sluggish charge transport kinetics, confined light absorption scope, limited active species, and rapid charge recombination rate. Herein, we conceptually demonstrate the elaborate design of all transition metal chalcogenides (TMCs)-comprising heterostructures via a facile, controllable, and precise cascade cation exchange strategy. This progressive route strategically extends the light absorption of TMCs, engenders elegant heterostructured interface, and furnishes favorable energy level alignment. The resultant TMCs heterostructures demonstrate markedly enhanced and multifarious photoactivities, owing predominantly to the robust interfacial electronic coupling and applicable energy level configuration among the building blocks, synergistically resulting in the reinforced charge transfer impetus and considerably prolonged charge lifespan. Our work would provide an emerging avenue to fine tuning of vectorial charge motion via such a judicious interface modulation strategy for solar-to-chemical energy conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Transition metal chalcogenides/MXene heterostructures were judiciously designed by a ligand-triggered self-assembly strategy. • Ti 3 C 2 T x (MXene) can serve as an efficient interfacial charge transfer mediator to prolong charge lifetime. • Multifarious photoreduction catalysis has been comprehensively probed. • The role of Ti 3 C 2 T x (MXene) as charge mediator has been evidenced to be universal. Transition metal chalcogenides quantum dots (TMCs QDs) demonstrate emerging potential in solar energy conversion owing to marvelous physicochemical properties, such as quantum size effect, large extinction coefficient, and multiple excitons generation. Nevertheless, TMCs QDs as photosensitizers are unstable owing to high surface energy, and moreover, substantial trap states of TMCs QDs annihilate the photo-induced charge carriers, thus resulting in ultra-short charge lifetime and inferior photoactivities. Herein, 0D/2D TMCs QDs/MXene heterostructures were designed by a ligand-initiated electrostatic self-assembly strategy, wherein positively charged TMCs QDs were anchored on the negatively charged ultrathin Ti 3 C 2 T x nanosheets (NSs) framework, which promotes the anisotropic unidirectional electron transport from TMCs QDs to MXene NSs. MXene functions as an effective charge mediator to decrease the charge recombination and prolong the charge lifetime for photocatalytic hydrogen generation and anaerobic reduction of nitroaromatics to amino compounds under visible light irradiation. Our work would shed new insights on the role of MXene in tuning the directional charge transport for solar energy conversion. [ABSTRACT FROM AUTHOR]

Abstract Background Platelet microparticles (PMPs) are closely associated with diabetic macrovascular complications. This study aimed to explore the underlying mechanisms of high glucose-induced PMPs generation. Methods Washed platelets, obtained from the plasma of healthy male Sprague-Dawley rats, were incubated with high glucose. PMPs were isolated using gradient centrifugation and counted by flow cytometry. Expression and activity of ROCK1 and caspase3 were evaluated by real-time PCR, Western blotting, and activity assay kit. Results High glucose enhanced PMPs shedding in the presence of collagen. The mRNA and protein levels of ROCK1, but not ROCK2, were increased in platelets incubated with high glucose. Y-27632, an inhibitor of ROCK, blocked the increased PMPs shedding induced by high glucose. Expression and activity of caspase3 were elevated in platelets under the high glucose conditions. Z-DVED-FMK, a caspase3 inhibitor, inhibited ROCK1 activity and decreased the PMPs generation under high glucose. Conclusion High glucose increased PMPs shedding via caspase3-ROCK1 signal pathway. Graphical abstract Image 1 Highlights • High glucose enhanced platelet microparticles shedding. • Caspase3 mediated activation of RCOK1 under high glucose. [ABSTRACT FROM AUTHOR]

This study aimed to improve the flavor of fermented soybean foods and to investigate the molecular mechanisms of this flavor improvement phenomenon. Three fermented soybean foods (Bv, BvLp and Lp) were obtained using Bacillus velezensis SDL1 and Lactiplantibacillus plantarum Ly8 as starter cultures. Organoleptic evaluation showed that BvLp had the best flavor, followed by Bv and Lp. Next, some flavor-related physicochemical properties were investigated. Acid production level was ranked as Lp > BvLp > Bv, in which acetic acid and lactic acid were the main contributors to the variation in sample acid content, and BvLp contained the most lactic acid and isovaleric acid, 3.72−49.62 and 3.61−37.75 times those of Lp and Bv, respectively. Free amino acid analysis showed that the concentration trends of branched-chain amino acids and threonine were consistent with the sensory evaluation. Volatile metabolomics analysis indicated that acetoin and pyrazines were the key compounds for the superior flavor of BvLp. Finally, transcriptomic analysis, combined with the above data, revealed that under a parasitic-like interaction in microbial mixed culture, BvLp had significantly more flavor than Bv and Lp by reducing the acid content and increasing the concentration of some esters, acetoin and pyrazines. [Display omitted] • Mix-fermented soybean products taste better than single bacterial fermentation. • Acetoin and pyrazines are the main flavor compounds of fermented soybean foods. • B. velezensis and Lb. plantarum show a parasite-like interaction in co-fermentation. [ABSTRACT FROM AUTHOR]

The study of parathyroid hyperplasia with bone disease as a critical manifestation of chronic kidney disease-mineral and bone disorders (CKD-MBDs) is challenging due to the lack of a suitable research model. Here, we established a rat model with secondary hyperparathyroidism (SHPT) and bone disease induced by adenine and a high phosphorous diet and analyzed the skeletal characteristics. We performed blood analysis, emission computed tomography (ECT), dual energy X-ray absorptiometry (DEXA), micro-computed tomography (micro-CT), bone histomorphometry, and bone mechanical tests. The CKD rats with SHPT induced by adenine and a high phosphorus diet showed severe abnormalities in calcium and phosphorus metabolism and exhibited parathyroid hyperplasia. The bone mineral density (BMD) of femurs and lumbar vertebrae was significantly lower in the CKD rats than in the control (CTL) rats. The cortical and trabecular bone parameters of femurs showed significant bone loss. In addition, we found decreases in ultimate force, work to failure, stiffness, and elastic modulus in the CKD rats. In conclusion, our findings demonstrated that the CKD rats with SHPT induced by adenine and a high phosphorus diet may serve as a useful model for skeletal analysis in CKD with SHPT. [ABSTRACT FROM AUTHOR]

For rapid nondestructive detection of classification and adulteration of Mengding Mountain green tea, an experimental method combining Fluorescence hyperspectral imaging technology and machine learning modeling method was proposed. Spectral data were preprocessed with Median Filtering (MF) and Multiplicative Scatter Correction (MSC), which can effectively reduce the effects of baseline drift and tilt. Xgboost (XGB) and Logistic Regression (LGR) were used for feature band extraction. Light Gradient Boosting Machine (LightGBM), Random Forest (RF), and CatBoost were used to build predictive models. The results show that the MF-LGR-RF algorithm model is the best model for the classification of Mengshan green tea, and its accuracy is 100%. The MF-XGB-CatBoost algorithm model is the best model for the quantitative analysis of the doping of Laochuan tea tree Ganlu. The R2 of the test set is 0.959 and the RMSE is 0.065. In order to further improve the model performance, a multi-model stacking ensemble learning model was designed to quantitatively analyze the adulteration of Laochuan tea tree Ganlu. The R2 of the test set was increased to 0.968 and the RMSE was reduced to 0.058. • Light scattering and light absorption characteristics of tea were revealed. • Various algorithms were selected for data noise reduction and feature extraction. • Design and build hot machine learning models of MF-LGR-RF and MF-XgBoost-CatBoost. • Optimize the stacking learning model to achieve more ideal model results. • The rapid non-destructive quality of the tea leaves of the detective was satisfactory. [ABSTRACT FROM AUTHOR]

IncC plasmids are of great concern as vehicles of broad-spectrum cephalosporins and carbapenems resistance genes bla CMY and bla NDM . The aim of this study was to sequence and characterize a multidrug resistance (MDR) IncC plasmid (pPm14C18) recovered from Proteus mirabilis . pPm14C18 was identified in a CMY-2-producing P. mirabilis isolate from chicken in China in 2014, and could be transferred to Escherichia coli conferring an MDR phenotype. Whole genome sequencing confirmed pPm14C18 was a novel type 1/2 hybrid IncC plasmid 165,992 bp in size, containing fifteen antimicrobial resistance genes. It harboured a novel MDR mosaic region comprised of a hybrid Tn 21 tnp -pDU mer , in which bla CTX-M-65 , dfrA32 and ereA were firstly reported in IncC plasmid. Phylogenetic relationship reconstruction based on the nucleotide sequences of the 52 IncC backbones showed all type 1 IncC plasmids were clustered into one clade, and then merged with pPm14C18 and finally with the type 2 IncC plasmids and another type 1/2 hybrid IncC plasmid pYR1. The MDR IncC plasmids in P. mirabilis of animal origin might threaten public health, which should be drawn more attention. [ABSTRACT FROM AUTHOR]

Recently, a novel variant of the CTX-M enzyme, CTX-M-98, was detected in Escherichia coli isolates from food animals. However, few plasmids carrying bla CTX-M-98 have been fully characterized. In this study, we sequenced the complete pHeBE7 plasmid, an 86,015-bp plasmid that contains the bla CTX-M-98b , bla TEM-1 , rmtB , and traT genes, using whole-genome sequencing. The backbone of pHeBE7 shows a high similarity (> 99%) to pMC-NDM, which carries the bla NDM-1 gene, however its mosaic regions remain relatively unique among sequenced plasmids. We discovered that a typical IS Ecp1 - bla CTX-M -IS 903 element in the mosaic region harbors the bla CTX-M-98b gene. Conjugation and growth competition assays indicate that pHeBE7 can be easily transmitted and that it confers a limited fitness cost to the recipient cell. The genetic characterization of pHeBE7 may improve our knowledge of how antibiotic resistance disseminates in enterobacteria. [ABSTRACT FROM AUTHOR]

Abstract: The apoptotic pathway in higher eukaryotes remains controversial with respect to the necessity of activation of caspase-3 in TRAIL (tumor necrosis factor-related apoptosis-inducing ligand)-treated cells. In this study, a fluorescence resonance energy transfer (FRET) probe was developed to image the activation of caspase-3 and the related apoptotic pathway in TRAIL-treated cells in real time. Both kinds of apoptotic pathways were observed simultaneously in the same experiment proceeding from activation and non-activation of caspase-3. The total apoptotic rate was 56.08%, the apoptotic rates for activation and non-activation of caspase-3 pathways were 21.5% and 34.58%, respectively, which were examined later for Hoechst 33258 staining and morphological characteristics. The apoptotic rate due to the activation of caspase-3 pathways in TRAIL-treated cells has been independently measured to be around 25.11% by capillary electrophoresis (CE) analysis, which confirmed the apoptotic rate due to activation of caspase-3 pathways as found by FRET analysis. This result also suggests that rest apoptosis is preceded by caspase-3-independent pathways, as CE has the ability to quantitatively detect caspase-dependent apoptosis. The observation of the coexistence of caspase-3-dependent and caspase-3-independent apoptotic pathways in the TRAIL-treated cells was unusual in comparison with the previous reports. [Copyright &y& Elsevier]