Genotype analysis of rotaviruses isolated from children during a phase III clinical trial with the hexavalent rotavirus vaccine in China.

The oral hexavalent live human-bovine reassortant rotavirus vaccine (RV6) developed by Wuhan Institute of Biological Products Co., Ltd (WIBP) has finished a randomized, placebo-controlled phase III clinical trial in four provinces of China in 2021. The trail demonstrated that RV6 has a high vaccine efficacy against the prevalent strains and is safe for use in infants. During the phase III clinical trial (2019-2021), 200 rotavirus-positive fecal samples from children with RV gastroenteritis (RVGE) were further studied. Using reverse transcription-polymerase chain reaction and high-throughput sequencing, VP7 and VP4 sequences were obtained and their genetic characteristics, as well as the differences in antigenic epitopes of VP7, were analyzed in detail. Seven rotavirus genotypes were identified. The predominant rotavirus genotype was G9P [8] (77.0%), followed by prevalent strains G8P [8] (8.0%), G3P [8] (3.5%), G3P [9] (1.5%), G1P [8] (1.0%), G2P [4] (1.0%), and G4P [6] (1.0%). The amino acid sequence identities of G1, G2, G3, G4, G8, and G9 genotypes of isolates compared to the vaccine strains were 98.8%, 98.2%-99.7%, 88.4%-99.4%, 98.2%, 94.2%-100%, and 93.9%-100%, respectively. Notably, the vaccine strains exhibited high similarity in amino acid sequence, with only minor differences in antigenic epitopes compared to the Chinese endemic strains. This supports the potential application of the vaccine in preventing diseases caused by rotaviruses.

Effects of Curing Conditions on Splitting Tensile Behavior and Microstructure of Cemented Aeolian Sand Reinforced with Polypropylene Fiber.

Aeolian sand is widely distributed in the Takramagan Desert, Xinjiang, China, which cannot be directly used as railway subgrade filling. It is beneficial for environmental protection to use fiber and cement-reinforced aeolian sand as railway subgrade filling. The present work is to explore the enhancement of tensile strength in cemented aeolian sand via the incorporation of polypropylene fibers under conditions of elevated temperature and drying curing. The purpose Is to delve into the examination of the temperature's impact on not only the mechanical attributes but also the microstructure of cemented aeolian sand reinforced with polypropylene fiber (CSRPF). For this, a comprehensive set of tests encompassing splitting tensile strength (STS) assessments and nuclear magnetic resonance (NMR) examinations is conducted. A total of 252 CSRPF specimens with varying fiber content (0, 6‱, 8‱, and 10‱) are tested at different curing temperatures (30 °C, 40 °C, 50 °C, 60 °C, 70 °C, and 80 °C). The outcomes of the NMR examinations indicate that elevating the curing temperature induces the expansion of pores within CSRPF, both in size and volume, consequently contributing to heightened internal structural deterioration. STS tests demonstrate that the STS of CSRPF decreases as the curing temperature increases. Meanwhile, the STS of CSRPF increases with fiber content, with optimal fiber content being 8‱. Regression models accurately predict the STS, with the curing temperature exhibiting the greatest influence, followed by the fiber content according to sensitivity analysis. The research results provide a valuable reference for the use of CSRPF as railway subgrade filling under high temperature and drying conditions.

Effects of Compound Probiotics on Cecal Microbiota and Metabolome of Swine.

Complex probiotics are made from various single probiotics mixed in scientific formula. The long-term intake of different probiotics is beneficial to maintain the intestinal microecological balance, inhibiting harmful pathogenic flora and facilitating organism health. Based on the limited research on intestinal flora and related metabolites after the long-term intake of the probiotic complex, in this study, 16S rRNA gene sequencing and untargeted metabolomics were used to further investigate the effects of the probiotic complex on the intestinal flora and metabolome of pigs. The results demonstrated that the content of flora in the intestinal tract or metabolites of pigs varied greatly and was related to cellular metabolic pathways after the long-term feeding of complex probiotics. This study provides a valuable theoretical basis for farmers to raise pigs scientifically and healthily.

Nomogram for predicting skip metastasis in cN0 papillary thyroid cancer patients at increased risk of lymph node metastasis.

BACKGROUND: Skip lymph node metastasis (SLNM) refers to lateral lymph node metastasis (LLNM) without involving central lymph node (CLN). Some microscopic nodal positivity may be difficult to detect before surgery due to atypical imaging characteristics. These patients are misdiagnosed as having clinically node-negative (cN0) papillary thyroid cancer (PTC) even after central lymph node dissection, leading to a high risk of developing LNM after surgery. Current prediction models have limited clinical utility, as they are only applicable to predict SLNM from clinically node-positive (cN+) PTC, not cN0 PTC, and this has little impact on treatment strategies. OBJECTIVES: This study aimed to establish a nomogram for preoperatively assessing the likelihood of SLNM in cN0 PTC patients with increased risk of LNM, thus optimizing their therapeutic options. MATERIAL AND METHODS: The records of 780 PTC patients undergoing thyroidectomy along with bilateral central lymph node dissection were retrospectively reviewed. The cN0 patients with postoperative LLNM (occult SLNM) and cN+ patients without central lymph node metastasis (CLNM) (typical SLNM) were included in the SLNM group (n = 82). The CLNM-negative cN0 patients without postoperative LLNM were assigned to the non-SLNM group (n = 698). The independent correlates of SLNM constituted the nomogram for determining the likelihood of SLNM in high-risk cN0 PTC patients. RESULTS: The independent correlates of SLNM were age (hazard ratio (HR) = 1.016), tumor location (HR = 1.801), tumor size (HR = 1.528), and capsular invasion (HR = 2.941). They served as components in the development of the nomogram. This model was verified to present acceptable discrimination. It showed good calibration and a decent net benefit when the predicted probability was <60%. CONCLUSIONS: We developed a nomogram incorporating preoperative clinical data to predict the probability of SLNM development in high-risk cN0 PTC patients, which contributed to their optimized treatment options.

Efficacy, safety and immunogenicity of hexavalent rotavirus vaccine in Chinese infants.

A randomized, double-blind, placebo-controlled multicenter trial was conducted in healthy Chinese infants to assess the efficacy and safety of a hexavalent live human-bovine reassortant rotavirus vaccine (HRV) against rotavirus gastroenteritis (RVGE). A total of 6400 participants aged 6-12 weeks were enrolled and randomly assigned to either HRV (n â€‹= â€‹3200) or placebo (n â€‹= â€‹3200) group. All the subjects received three oral doses of vaccine four weeks apart. The vaccine efficacy (VE) against RVGE caused by rotavirus serotypes contained in HRV was evaluated from 14 days after three doses of administration up until the end of the second rotavirus season. VE against severe RVGE, VE against RVGE hospitalization caused by serotypes contained in HRV, and VE against RVGE, severe RVGE, and RVGE hospitalization caused by natural infection of any serotype of rotavirus were also investigated. All adverse events (AEs) were collected for 30 days after each dose. Serious AEs (SAEs) and intussusception cases were collected during the entire study. Our data showed that VE against RVGE caused by serotypes contained in HRV was 69.21% (95%CI: 53.31-79.69). VE against severe RVGE and RVGE hospitalization caused by serotypes contained in HRV were 91.36% (95%CI: 78.45-96.53) and 89.21% (95%CI: 64.51-96.72) respectively. VE against RVGE, severe RVGE, and RVGE hospitalization caused by natural infection of any serotype of rotavirus were 62.88% (95%CI: 49.11-72.92), 85.51% (95%CI: 72.74-92.30) and 83.68% (95%CI: 61.34-93.11). Incidences of AEs from the first dose to one month post the third dose in HRV and placebo groups were comparable. There was no significant difference in incidences of SAEs in HRV and placebo groups. This study shows that this hexavalent reassortant rotavirus vaccine is an effective, well-tolerated, and safe vaccine for Chinese infants.

Experimental Investigation of the Mechanical Properties of the Sand-Concrete Pile Interface Considering Roughness and Relative Density.

The aim of this study was to investigate the effect of roughness and relative density on the mechanical properties of sand-concrete pile interface. A series of direct shear tests were carried out on the interface using a large-scale direct shear apparatus with various relative densities of sand (73%, 47%, and 23%) and concrete blocks with four roughness values (I = 0, 10, 20, and 30 mm). Various mechanical properties (such as shear stress, volume change, peak shear strength, secant friction angle, and normalized friction coefficient) from the interface tests were compared with trends obtained from the pure sand direct shear test. For the smooth interface, the shear stress-horizontal displacement curves of the dense sand specimen exhibited a slight softening response, which became more apparent as the roughness increased. The curves of the loose sand specimen demonstrated a hardening response. The volumetric response was influenced by the combination of normal stress, relative density, and roughness. The peak shear strength demonstrated a nonlinear increasing trend as the normal stress increased. With an increase in the normal stress, the secant friction angle and peak friction coefficient decreased as exponential and power functions, respectively. Additionally, a critical roughness value Icr resulted from the tests, which halted the upward trend of the peak friction coefficient and normalized the secant friction angle when I exceeded Icr.

Regulatory mechanism of montmorillonite on antibiotic resistance genes in Escherichia coli induced by cadmium.

The emergence and spread of antibiotic resistance genes (ARGs) induced by the overuse of antibiotics has become a serious threat to public health. Heavy metals will bring longer-term selection pressure to ARGs when the concentration of their residues is higher than that of antibiotics in environmental media. To explore the potential roles of montmorillonite (Mt) in the emergence of ARGs under divalent cadmium ion (Cd2+) stress, Escherichia coli (E. coli) was induced continuously for 15 days under Cd2+ gradient concentrations (16, 32, 64, 96, and 128 µg∙mL-1) with and without Mt. Subsequently, antibiotic resistance testing, transcriptomics, transmission electron microscope, scanning electron microscopy, and Fourier transform infrared were conducted for analysis. The results of characterization analysis showed that Cd2+could enhance the expression of resistance genes such as penicillin, tetracycline, macrolactone, and chloramphenicol in E. coli. Moreover, compared with Cd2+, Mt-Cd could inhibit the promotion of these resistances by alleviating the expressions of genes involved in cell wall/membrane, protein synthesis, transport systems, signal transduction, and energy supply processes. Therefore, the study promoted the understanding of Cd2+ in triggering bacterial antibiotic resistance and highlighted a novel theme of clay's ability to mitigate ecological risk of antibiotic resistance caused by heavy metals. KEY POINTS: • Montmorillonite (Mt) could inhibit the promotion of antibiotic resistances. • E. coli formed a unique resistance mechanism by interacting with Mt and Cd2+. • Mt stimulated cellular signal transduction, cellular component, and energy supply.

Activation of NLRP3-Caspase-1 pathway contributes to age-related impairments in cognitive function and synaptic plasticity.

Aging is characterized by a progressive deterioration in physiological functions that is associated with cognitive decline as well as other physical functional impairments. Microglia activation leading to neuroinflammation has been generally recognized as playing a critical role in the development of age-related cognitive decline. NLRP3 inflammasome in microglia is fundamental for IL-1ß maturation and subsequent inflammatory events. However, it remains unknown whether NLRP3 activation contributes to aging-induced cognitive decline in vivo. Here, our study demonstrated that aging rats showed declined cognitive function and impaired synaptic plasticity as well as decreased density of dendritic spines. Importantly, our data demonstrated strongly enhanced expression of NLRP3, ASC and Caspase-1 in the hippocampus of aged rats as well as decreased AMPA receptor and phosphorylated levels of CaMKII and CREB in the hippocampus of natural aging rats. Furthermore, NLRP3 inflammasome inhibitor elevated the surface expression of AMPA receptor and the phosphorylated levels of CaMKII, CREB in hippocampus, and finally contributed to the attenuation of hippocampal long-term potentiation (LTP) deficits and the improvement of cognitive decline of natural aging rats. These results revealed an important role for the NLRP3-Caspase-1 pathway in aging-induced cognitive decline and suggested that inhibition of NLRP3 inflammasome represented a novel therapeutic intervention for aging-related cognitive impairment.

Chitosan/Polyvinyl Alcohol/ Lauramidopropyl Betaine/2D-HOF Mixed Film with Abundant Hydrogen Bonds Acts as High Mechanical Strength Artificial Skin.

The mechanical properties of artificial skins are complicated to maintain under ensuring air permeability and antimicrobial. Thus, a series of hydrophilic antimicrobial polymer networks are prepared by crosslinking chitosan and polyvinyl alcohol with the lauramidopropyl betaine and hydrogen bond organic framework (CS/PVA/LPB/2D-HOF). The mechanical performance of the control groups and the complex are systematically evaluated to attain an artificial strength skin. The CS/PVA/LPB/2D-HOF complex exhibits strong mechanical abilities than other control groups. By analyzing the IR spectra and the morphology, the synergistic effect of hydrogen bonds between molecules and cracks significantly improves the mechanical properties of the complex. Its maximum tensile strength can reach 29 MPa, and its maximum load capacity can reach 3700 g. Notably, the composite membrane also performs an excellent antimicrobial activity. In vivo and in vitro experiments show that the hybrid membrane can promote tissue regeneration and wound healing (95％). These results may open up the opportunity for future composite material investigations in the artificial skin and tissue engineering field.

Kaolinite weakens the co-stress of ampicillin and tetracycline on Escherichia coli through multiple pathways.

Ampicillin and tetracycline are common antibiotics and can threaten humans by inducing antibiotic resistance in bacteria. Microorganisms are usually exposed to a mixed antibiotic system in the environment. However, there are few researches on the specific regulatory mechanisms of clay on microorganisms under the stress of complex antibiotics. In this study, tandem mass tag-based coupled with two-dimensional liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) was employed to recognize and quantify changes in protein expression of Escherichia coli (E. coli) after culture for 15 days, with or without kaolinite in the co-stress of ampicillin and tetracycline. The results indicated that kaolinite could activate metabolic pathways of E. coli such as the energy metabolism, the biosynthesis of other secondary metabolites, and the metabolism of cofactors and vitamins. Particularly, the fatty acid degradation pathway has also been promoted, indicating that in the same unfavorable environment, kaolinite might influence the composition of E. coli cell membranes. This might be due to the change in membrane composition that was a kind of adaptive strategy of bacterial evolution. Moreover, kaolinite could promote multidrug efflux system to export the bacterial intracellular toxic substances, making E. coli survive better in an adverse environment. Consequently, this study not only disclosed the regulation of kaolinite on E. coli in a complex antibiotic environment but also provided new insights into the environmental process of antibiotic resistance.

Design and Synthesis of Polyimide Covalent Organic Frameworks.

As a subseries of the covalent organic framework (COF) material family, polyimide-based covalent organic framework (PI-COF) material, which has the advantages of high stability of polyimide, high specific surface area, and controllable pores of COF material, is expected to be a new type of porous material with potential applications. Although the development of PI-COF is in the early stages during the past decade, it has attracted extensive attention and is widely used in heterogeneous catalysis, gas separation, and storage fields. Therefore, this review is aiming to give a comprehensive understanding of the recent progress of PI-COFs. This article summarizes the progress of PI-COF from three aspects: controllable structure design, synthesis method, and application. First of all, under the guidance of network chemical design principles, the topology type of PI-COF and the size and shape of the formed pores are summarized in terms of different organic monomers. Then the five synthetic strategies for the synthesis of PI-COF are analyzed. Finally, the applications of PI-COF in adsorption and separation, drug delivery, solar-to-electrochemical energy storage, photocatalysis, and electrocatalyst are introduced.

UiO-66 derivate as a fluorescent probe for Fe3+ detection.

The fluorescent dye molecules have gained wide attention for their applications in areas such as imaging and sensor. However, the properties of the fluorescent dyes are limited due to the built-in problems such as the aggregation-caused quenching (ACQ). Herein, a fluorescent dye@MOF was developed by encapsulating fluorescent dye molecules into the channels of metal-organic frameworks (MOFs) to disperse them. This composite material SRB@UiO-66, equipping appreciable stability, was successfully obtained with sulfonyl rhodamine B (SRB) integrated into UiO-66. The composite material overtly accelerated the fluorescence property of SRB due to the limitation of nanometer channels on SRB, while UiO-66 has some fluorescence properties. Besides, SRB@UiO-66 with dual emission centers can be utilized as ratiometric sensors for Fe3+ detection in aqueous solution owing to their high sensitivity and selectivity. SRB@UiO-66 shows a new possibility to fabricate fluorescent molecular probes for the determination of heavy metal ions.

Quantitative proteomic analysis reveals the mechanisms of polymyxin B toxicity to Escherichia coli.

Polymyxin B is increasingly employed all over the world to treat patients who affected by multidrug-resistant Gram-negative bacteria. Although the mechanism of resistance to polymyxin B is well known, the metabolic role of bacteria in stress response to polymyxin B remains an important task and may help to better understand polymyxin B-related stress response. In this study, the proteome changes of Escherichia coli (E. coli) continuously induced in concentrations of 1.0 mg/L and 10.0 mg/L polymyxin B were revealed. Compared to E. coli (PMB0), E. coli exposed to polymyxin B at 1.0 mg/L (PMB1) and 10.0 mg/L (PMB10) resulted in 89 and 314 differentially expressed proteins (DEPs), respectively. Such differences related to fatty acid degradation, quorum sensing and two-component regulatory system pathways. Based on absolute quantitative (iTRAQ) proteomics analysis, this study comprehensively studied the changes of E. coli proteome in culture with concentrations of 1.0 mg/L and 10.0 mg/L polymyxin B through confocal laser scanning microscopy observation, cell viability detection and reactive oxygen species analysis. The results showed that E. coli cultured at concentration of 10.0 mg/L polymyxin B increased the expression levels of multidrug-resistant efflux transporters and efflux pump membrane transporters, which might further improve the pathogens of polymyxin B-resistant bacteria lastingness and evolution. It has emerged globally to resist polymyxin B. The reuse of polymyxin B should be aroused public attention to avoid causing more serious environmental pollution. These findings could provide new insights into polymyxin B-related stress.

Adhesion of Sphingomonas sp. GY2B onto montmorillonite: A combination study by thermodynamics and the extended DLVO theory.

Bacterial adhesion on mineral surface are of fundamental importance in geochemical processes and biogeochemical cycling, such as mineral transformation and clay-mediated biodegradation. In this study, thermodynamics analysis combined with classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory as well as the extended DLVO (XDLVO) theory were employed to investigate the adhesion of the Gram-negative PAH-degrading bacteria Sphingomonas sp. GY2B on montmorillonite (Mt). Scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS) indicated the affinity of GY2B for Mt, and the experimental results could be described well by pseudo-second-order (R2 = 0.997) and Langmuir model (R2 = 0.995). The thermodynamics analysis revealed the physical nature of bacterial adhesion onto Mt, which was confirmed by the XDLVO theory. The related surface properties (Zeta potential, hydrodynamic diameter and hydrophobicity) at different ionic strength were determined and the interaction energy between Mt and GY2B were also calculated using the DLVO and XDLVO theories in KCl or CaCl2 solution. At low ionic strength (≤ 20 mM), GY2B adhesion onto Mt was primarily driven by long-range DLVO forces (e.g. electrostatic repulsion), while short-range (separation distance < 5 nm) Van der Waals and hydrophobic interactions played more important roles in the bacterial adhesion at higher ionic strength (50-100 mM). In addition, Mt had a better adhesion capacity to bacteria in Ca2+ solution than that in K+ solution, owing to less negative charge and lower energy barrier in mineral-bacteria system in Ca2+ solution. Overall, the adhesion of bacteria onto Mt could be evaluated well on the basis of the XDLVO theory along with thermodynamics analysis. This study provides valuable insights into the clay-mediated microbial remediation of hydrophobic organic contaminants in the environment.

The Fluorescence Property of Zirconium-Based MOFs Adsorbed Sulforhodamine B.

Sulforhodamine B (SRB) is widely utilized for cell staining and laser field. But its application is limited by aggregation-caused quenching (ACQ). In this work, we evaluated the use of UiO-66 and UiO-67 of Zr-based metal organic frameworks (Zr-MOFs) as the host to adsorb SRB molecules due to the high stabily and good loading capacity of Zr-MOFs. The fluorescence properties of the compounds were then discussed respectively. Due to the aperture difference between UiO-66 and UiO-67, they showed distinct fluorescence properties after loading SRB. When the concentration reaches 5 ppm, fluorescence quenching begins to occur in SRB@UiO-66, while it occurs in SRB@UiO-67 at 2 ppm. The solution of quenching phenomenon could open new avenues for the extensive use of SRB.

The regulatory mechanism of Chryseobacterium sp. resistance mediated by montmorillonite upon cadmium stress.

Cadmium (Cd) is a toxic heavy metal and its uptake by living organisms causes adverse effect, further resulting in cycle pollution of the biosphere. The specific regulatory mechanism between clays and microbes under Cd stress remains unclear. In this study, interface interactions among clays, microbes and Cd were confirmed. Comparative transcriptome was conducted to investigate how it regulated gene expression patterns of microbes (Chryseobacterium sp. WAL2), which exposed to a series of gradient concentrations of Cd (16, 32, 64 and 128 µg mL-1) for 12 d in the presence and absence of clay montmorillonite (Mt) (16 g L-1). Cd was highly enriched by the unique interface interactions between Mt and bacteria (67.6-82.1%), leading to a more hostile environment for bacterial cells. However, Mt ultimately enhanced bacterial resistance to Cd stress by stimulating the mechanism of bacterial resistance; namely: (i) Mt increased genes expression connected with ion transport, enhancing the uptake of Cd; (ii) Mt stimulated genes expression related to efflux pump and positively regulated cellular oxidative stress (e.g., glutathione) and Cd accumulation (e.g., cysteine) processes. Further, genes expression related to intracellular metabolic processes was enforced, which supplied a driving force and accelerated electron transfer; (iii) Mt improved genes expression involved in DNA replication and other biological processes (e.g., terpenoid backbone biosynthesis) to maintain bacterial vitality. Therefore, the study not only optimized a unique Cd resistance mechanism of Mt on Chryseobacterium sp., but also provided a novel insight for environmental mitigation of heavy metals from the perspective of molecular biology.

Batch interaction of emerging tetracycline contaminant with novel phosphoric acid activated corn straw porous carbon: Adsorption rate and nature of mechanism.

In this work, corn straw (CS) based porous carbon was prepared by one-step phosphoric acid (H3PO4) low temperature activation. The impregnation ratios (H3PO4/CS, g/g) played an important role in the pore development. ACS300-1 engineered at 300 °C and the impregnation ratio of 1.0 showed the maximal specific surface area of 463.89 m2/g with total pore volume of 0.387 cm3/g, attaining a high tetracycline (TC) uptake of 227.3 mg/g. The adsorption of TC onto ACS300-1 was found tolerant with wide pH (2.0-10.0) and high ionic strength (0 - 0.5 M). The adsorption data can be fitted well by the pseudo-second order kinetic model and Langmuir isotherm model. The endothermic and spontaneous properties of the adsorption system was implied by Thermodynamic study. The findings of the current work conclude that one-step H3PO4 activation is a green and promising method for corn straw based porous carbon that may be found with great potentials in antibiotic containing wastewater treatment.

[Improved effects of saponins from Panax japonicus on decline of cognitive function in natural aging rats via NLRP3 inflammasome pathway].

The aim of this paper was to investigate the effect of total saponins from Panax japonicus( SPJ) on cognitive decline of natural aging rats and its mechanism. Thirty male SD rats of eighteen month old were randomly divided into three groups: aged group,10 mg·kg~(-1) SPJ-treated group and 30 mg·kg~(-1) SPJ-treated group. The SPJ-treated groups were given SPJ at the dosages of 10 mg·kg~(-1) and 30 mg·kg~(-1),respectively,from the age of 18 to 24 months. Aged group were lavaged the same amount of saline,10 six-month-old rats were used as control group,with 10 rats in each group. The open field test,novel object recognition and Morris water maze were performed to detect the changes of cognitive function in each group. The changes of synaptic transmission of long-term potentiation( LTP) in hippocampal CA1 region were detected by field potential recording. Western blot was used to detect the protein levels of NLRP3,ASC,caspase-1 and the changes of Glu A1,Glu A2,CAMKⅡ,CREB and phosphorylation of CAMKⅡ,CREB in each group.The results showed that SPJ could improve the decline of cognitive function in aging rats,reduce the damage of LTP in the hippocampal CA1 region of aged rats,and decrease the expression of NLRP3,ASC,caspase-1 in aging rats. At the same time,SPJ could enhance the membrane expression of AMPA receptor( Glu A1 and Glu A2),and increase the expression of p-CAMKⅡand p-CREB in aging rats.SPJ could improve cognitive decline of natural aging rats,and its mechanism may be related to regulating NLRP3 inflammasome,thus regulating the membrane expression of AMPA receptor,and enhancing the expression phosphorylation of CAMKⅡ and CREB.

Immobilization of Sphingomonas sp. GY2B in polyvinyl alcohol-alginate-kaolin beads for efficient degradation of phenol against unfavorable environmental factors.

In this study, batch experiments were carried out to evaluate the biodegradation of phenol by Sphingomonas sp. GY2B, which were immobilized in polyvinyl alcohol (PVA)-sodium alginate-kaolin beads under different conditions. The optimal degradation performance was achieved by GY2B immobilized in beads containing 1.0% (w/v) of kaolin, 10% (w/v) of PVA, 0.3% (w/v) of sodium alginate, 10% (v/v) of biomass dosage, and exposed to an initial phenol concentration of 100 mg/L. The experimental results indicated that PVA-sodium alginate-kaolin beads can accelerate the degradation rate of phenol by reducing the degradation time and also improve degradation rate. The biodegradation rate of phenol by immobilized cells (16.79 ±â€¯0.81 mg/(L·h)) was significantly higher than that of free cells (11.49 ±â€¯1.29 mg/(L·h)) under the above optimal conditions. GY2B immobilized on beads was more competent than free GY2B in degradation under conditions with high phenol concentrations (up to 300 mg/L) and in strong acidic (pH = 1) and alkaline (pH = 12) environments. Higher phenol concentrations inhibit the biomass and reduce the biodegradation rate, while the lower biodegradation rate at low initial phenol concentrations is attributed to mass transfer limitations. The Haldane inhibitory model was in agreement with the experimental data well, revealing that phenol showed a considerable inhibitory effect on the biodegradation by Sphingomonas sp. GY2B, especially at concentrations higher than 90 mg/L. Intra-particle diffusion model analysis suggests that adsorption of phenol by immobilized beads was controlled by both rapid surface adsorption as well as pore diffusion mechanism. It's worth noting that the presence of 1 mg/L Cr(VI) enhanced the biodegradation of phenol by free cells, while Cr(VI) showed no obvious impact on the removal of phenol by immobilized cells. In addition, immobilized cells were reused 16 times and removed 99.5% phenol, and when stored at 4 °C for 90 days, more than 99% phenol was removed. These results showed that immobilized cells can significantly improve the microbial degradation performance, and protect microorganisms against unfavorable environment. It is implied that PVA -sodium alginate-kaolin beads have great potential to be applied in a practical and economical phenolic wastewater treatment system.

Hydrogen Sulfide Reverses Aging-Associated Amygdalar Synaptic Plasticity and Fear Memory Deficits in Rats.

As an endogenous neuromodulator, hydrogen sulfide (H2S) exerts multiple biological effects in the brain. Previous studies have shown that H2S is involved in the regulation of neural synaptic plasticity and cognition in healthy rodents. It is well known that there is a progressive decline of cognitive function that occurs with increased age. The purpose of this study was to investigate the role of H2S in aging-associated amygdalar synaptic plasticity and cued fear memory deficits as well as to explore the underlying mechanisms. We found that H2S levels in the amygdala were significantly lower in aged rats when compared with healthy adult rates, which displayed significant deficits in long-term potentiation (LTP) in the thalamo-lateral amygdala (LA) pathway and amygdala-dependent cued fear memory. Bath application of an H2S donor, sodium hydrogen sulfide (NaHS), significantly reversed the impaired LTP in brain slices from aged rats, and intra-LA infusion of NaHS restored the cued fear memory in aged rats. Mechanismly, we found that H2S treatment significantly enhanced NMDAR-mediated synaptic responses in the thalamo-LA pathway of aged rats. Notably, GluN2B-containing NMDARs, but not GluN2A-containing NMDARs, contributed to the effects of H2S on aging-associated impairments of amygdalar LTP and fear memory, because applying GluN2B antagonist could abolish the beneficial effects of NaHS treatment on amygdalar LTP and cognitive performance in aged rats. Collectively, these results show that H2S can reverse aging-associated amygdalar synaptic plasticity and fear memory deficits by restoring the function of GluN2B-containing NMDARs, suggesting that supplement of H2S might be a therapeutic approach for aging-related cognitive disorders.