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State-owned listed companies in the commercial category in Shanghai and Shenzhen A-shares from 2013 to 2020 were selected as the research sample. Data related to the shareholding and delegated behavior of private shareholders among the top ten shareholders are utilized. Using a fixed-effects model, we empirically analyze the impact of private companies' participation in the mixed reform of state-owned enterprises on the value preservation and appreciation of state-owned assets at the equity level and the management right level. Explore the moderating effects of internal control and the level of market-oriented development on the above relationships. The study shows that the participation of private enterprises in the mixed reform of SOEs can effectively contribute to the value preservation and appreciation of state-owned assets, both at the equity level and at the management level. Meanwhile, the level of internal control of SOEs has a significant positive moderating effect on the relationship between the participation of private firms in SOEs' mixed reform and the value-added of SOEs' assets; The participation of private firms can effectively compensate for the impact of insufficient market development on the value-added of SOEs' assets.

Scientific and accurate assessment of the comprehensive benefits and regional differences of state-owned mixed-owned enterprises is an important link in promoting the steady progress of mixed-ownership reform of state-owned enterprises and achieving high-quality development of the state-owned economy. Using factor analysis method and GA-BP neural network model to evaluate the comprehensive benefits of listed state-owned mixed enterprises, the results show that, first, the main factors affecting the comprehensive benefits of state-owned mixed enterprises are profitability factor, sustainability factor and solvency factor, and the effect is as follows: profitability factor>sustainability factor>solvency factor; second, factor analysis effectively improves the evaluation performance of the GA-BP neural network model. Further analysis of regional differences, it is found that the average comprehensive benefit of regional state-owned mixed enterprises is: eastern region > central region > western region. Among them, the profitability factor and solvency factor are as follows: eastern region>central region>western region, and the size of sustainability factor is: eastern region>western region>central region. Therefore, we can start from deepening the classification reform of state-owned enterprises, increasing investment in innovation, reducing financial leverage, and improving regional linkages, so as to improve the profitability, solvency and sustainability of enterprises, narrow regional differences, and achieve coordinated development between regions.

Exploring the governance modes of private listed enterprises, this paper divides private listed enterprises into categories of small, medium and large. The governance modes of private listed enterprises can be divided into 9 categories according to two different management intensities of equity capital governance and manpower capital governance. The 9 categories of governance modes of private listed enterprises are identified by using the BP neural network mode. This paper analyses the evolution of private listed companies’ governance modes at different scales and analyses various governance modes. Therefore, small, medium and large private listed companies choose the “strong equity and weak manpower”, “moderate equity and moderate manpower” and “weak equity and moderate manpower” governance modes, respectively. This paper comparatively analyses the governance efficiency of governance modes at different scales. The results show that “moderate equity and moderate manpower” is the most effective management mode for all three scales.

Two new genera and six new species of trilobites are systematically documented herein: Sinagnostus mirabilis new genus new species, Yanpingia punctata n. gen. n. sp., Illaenus taoyuanensis n. sp., Panderia striolatus n. sp., Nileus yichongqiaoensis n. sp., and Paratiresias peculiaris n. sp. The materials were collected from the Darriwilian (late Middle Ordovician) strata in the Upper Yangtze Region, South China. Also provided is an emended diagnosis of the genus Paratiresias based on the new species Paratiresias peculiaris, which is the oldest known species of this genus with an extremely narrow (sag. and exsag.) preglabellar field. Those Chinese species previously referred to Nanillaenus are reassigned to Illaenus sensu lato. These trilobites add new data for the Darriwilian trilobite macroevolution and show highly endemic to South China and the faunal exchanges between South China and Tarim, Kazakhstan, Alborz, as well as Sibumasu and North China.UUID: http://zoobank.org/ec3be9be-b003-4367-910d-7a0ac4edc982

Ketamine can produce rapid-acting antidepressant effects in treatment-resistant patients with depression. Although alterations in glutamatergic and GABAergic neurotransmission in the brain play a role in depression, the precise molecular mechanisms in these neurotransmission underlying ketamine's antidepressant actions remain largely unknown. Mice exposed to FSS (forced swimming stress) showed depression-like behavior and decreased levels of GABA (γ-aminobutyric acid), but not glutamate, in the hippocampus. Ketamine increased GABA levels and decreased glutamate levels in the hippocampus of mice exposed to FSS. There was a correlation between GABA levels and depression-like behavior. Furthermore, ketamine increased the levels of enzymes and transporters on the GABAergic neurons (SAT1, GAD67, GAD65, VGAT and GAT1) and astrocytes (EAAT2 and GAT3), without affecting the levels of enzymes and transporters (SAT2, VGluT1 and GABA

Four proetid trilobite species, Chuanqianoproetus guizhouensis Yin in Yin and Li, 1978, C. shuangheensis Wu, 1977, C. sp., and Latiproetus guizhouensis Yin in Yin and Li, 1978, are described from the Ningqiang Formation in Ningqiang County, Shaanxi, China. They are middle Telychian (Llandovery, Silurian) in age. Chuanqianoproetus and Latiproetus are both regarded as members of the subfamily Warburgellinae; the former has been considered to be a junior subjective synonym of Astroproetus, but on the basis of its morphology we argue here that they represent two independent genera. The poorly sorted bioclastic grainstones containing trilobite sclerites may indicate their deposition in turbulent conditions on an open marine platform.

Chronic neuropathic pain is frequently accompanied by memory impairment, yet the underlying mechanisms remain unclear. Here, we showed that mice displayed memory impairment starting at 14 days and lasting for at least 21 days after chronic constriction injury (CCI) of unilateral sciatic nerve in mice. Systemic administration of the pan histone deacetylase (HDAC) inhibitor sodium butyrate attenuated this memory impairment. More specifically, we found that hippocampus HDAC3 was involved in this process because the levels of its mRNA and protein increased significantly in the hippocampus at 14 and 21 days after CCI, but not sham surgery. Systemic administration of the selective HDAC3 antagonist RGFP966 attenuated CCI-induced memory impairment, improved hippocampal long-term potentiation impairment, and rescued reductions of dendritic spine density and synaptic plasticity-associated protein in the hippocampus. In addition, HDAC3 overexpression in the hippocampus led to memory impairment without affecting basal nociceptive responses in naive mice. Our findings suggest that HDAC3 contributes to memory impairment after CCI by impairing synaptic plasticity in hippocampus. Histone deacetylase 3 might serve as a potential molecular target for therapeutic treatment of memory impairment under neuropathic pain conditions.

The selective and quantitative detection of H2O2 is important for its employment in physiological, environmental and industrial applications. In this paper, a sensitive and selective strategy for H2O2 detection was established based on the fluorescence quenching of CdSe@ZnS quantum dots (QDs) by H2O2-mediated etching process of Ag nanoclusters (AgNCs). In this strategy, dihydrolipoic acid (DHLA) modified AgNCs were applied as H2O2 response group, the existence of H2O2 could initiate the oxidation of AgNCs and the production of Ag+. CdSe@ZnS QDs are very sensitive to Ag+, which could give rise to the effective fluorescence quenching of CdSe@ZnS QDs. Based on this strategy, the present fluorescent assay could realize the quantification detection of H2O2 and the limit of detection is calculated to be 0.3 μM under the optimum conditions. Furthermore, CdSe@ZnS/AgNCs hybrid-based probe was applied to detecting H2O2 in milk samples and showed a good recoveries results ranged from 95.8% to 112.0%, meaning the potential applicability of this strategy.

Autophagy is well-known as a common cellular response to nanomaterials. As one of the most comprehensively studied carbon-based nanomaterials, fullerene and its derivatives have been reported to bring about autophagic features in various cell lines, but little is known about the role of fullerenol (C60(OH)44) on the modulation of autophagy in human gastric tumor cell line SGC-7901. Fullerenol treatment led to the accumulation of autophagosomes, as evidenced by the increased fluorescent intensity of monodansylcadaverine (MDC) staining cells, an elevated level of LC3 protein, and the observation of auotphagosomes in cytoplasm. Subsequent results of the p62 level demonstrated that the accumulation of autophagosomes resulted from the blockade of autophagic flux rather than the activation of autophagy. Fullerenol disrupted autophagic flux by impairing lysosomal function, including lysosome membrane permeabilization (LMP), alkaline of lysosomes, and reduced activity of capthesin B. Interestingly, fullerenol tre...

A highly selective and sensitive nanoprobe with fluorescence turn-on sensing properties for recognizing Cd2+ was developed through replacing Mn2+ near the surface of Mn:ZnSe quantum dots (QDs). The similar ionic radii of Cd2+ and Zn2+ make the replacement of superficial Zn2+ by Cd2+ possible, followed by the replacement of external Mn2+ by Cd2+. Thus, this fluorescence turn-on strategy possesses great selectivity for the determination of Cd2+. Based on this strategy, the limit of detection (LOD) for Cd2+ is 18 nM, which is superior to the LOD of most reported fluorescent nanomaterial-based probes.

Understanding the interaction mechanism between proteins and surfactants is conducive to the application of protein/surfactant mixtures in the food industry. The present study investigated the interaction mechanism of casein with cationic Gemini surfactant (BQAS), anionic Gemini surfactant (SGS), anionic single-chain surfactant (sodium dodecyl sulfate [SDS]), and two biosurfactants (rhamnolipid [RL] and lactone sophorolipid [SL]) at the interface and in bulk phase. BQAS/casein and SDS/casein mixtures exhibit a strong synergistic effect on the surface activity. For SGS, RL, and SL, the formation of surfactant/casein complexes caused no improvement in surface activity. Dilational elasticity results indicate the displacement of casein by SGS, RL, and SL at the surface. However, the BQAS/casein complexes manifested varying dilational properties from pure casein surface. The strong electrostatic interaction between BQAS and casein produced large-size precipitate particles. For other surfactants, no precipitate particles formed. Determination of ζ-potential, UV-vis absorption spectra, and fluorescence spectra demonstrated the stronger interaction of BQAS and SDS with casein than that of SGS, RL, and SL. Addition of BQAS initially increased and then decreased the α-helix structure of casein. For SGS, RL, and SL, no noticeable change occurred in the casein structure. However, the formation of SDS/casein complexes was conducive to the casein structure. In conclusion, the interaction between BQAS and casein is similar to that of cationic single-chain surfactant. Furthermore, SGS exhibits a significantly different interaction mechanism from the corresponding monomer (SDS), possibly resulting from its excellent interfacial activity, low critical micelle concentration values, and strong self-assembly capability. For RL and SL, the weak interaction is attributed to the relatively complicated structure and less charged degree of hydrophilic headgroups.

Twelve trilobite species assigned to 11 genera are described from the Lower Unit of the Dawan Formation at the Huanghuachang section of Yichang, Hubei, southern China, which has been ratified by the International Union of Geological Sciences (IUGS) as the Global Stratotype Section and Point (GSSP) for the base of the Middle Ordovician Series and the Third Stage (Dapingian) of the Ordovician System. Of these trilobites, five species, i.e., Carolinites genacinaca genacinaca, Ovalocephalus eoprimitivus, Rhombampyx chinensis, Taihungshania tachengssuensis, and Niobe (Niobella) obscura n. sp., occur in the lowermost part of the Dawan Formation, and are restricted to the upper part of the Oepikodus communis conodont biozone to the lower part of the Oepikodus evae Biozone. Two species, Liomegalaspides taningensis and Pseudocalymene transversa, are distributed almost throughout the Lower Unit of the Dawan Formation; two taxa, Annamitella sp. and Mioptychopyge sp., are recorded from the middle part and upper part of the Oepikodus evae Biozone, respectively; and two other species, Rhombampyx yii and Aulacopleura (Paraaulacopleura) dawanensis, appear in the upper part of the Lower Unit of the Dawan Formation, which is referred to the Middle Ordovician Microzarkodina flabellum-Baltoniodus triangularis Biozone. Agerina parva has a shorter range, across the Lower–Middle Ordovician boundary. The fauna is dominated by Liomegalaspides taningensis, which is assigned to the Liomegalaspides Biofacies, and indicates an inner-shelf environment. For regional chronostratigraphic correlation, the occurrence of the middle–late Floian (approximately Corymbograptus deflexus Zone) forms Carolinites genacinaca genacinaca and Taihungshania tachengssuensis in the fauna is of great significance: the former, a pelagic trilobite species, occurs extensively in North America, East Siberia, Novaya Zemlya, and Spitsbergen; the latter is widely distributed in the Yangtze Region, occurring in Sichuan, Guizhou, Yunnan, southern Shaanxi, and eastern Anhui as well as in Hubei. The trilobites of the fauna are mostly typical of the South China Plate and eastern Peri-Gondwana, but the presence of Agerina and Niobe (Niobella) suggests faunal links with coeval Baltoscandian assemblages, and the occurrence of Rhombampyx is indicative of a Laurentian affinity.

Both environmental stress and immune challenge can induce abnormal neurobehavior. However, the impact of chronic stress on immune challenge-related neurobehavioral abnormalities is still controversial. Hence, we aimed to investigate the effects of chronic stress on immune challenge-related neurobehavioral abnormalities and explore the possible underlying mechanisms. During the first set of experiments, mice were reared under normal condition (NC) or chronic stress (CS) for 4 consecutive weeks. They were allocated to the following four groups: NC + normal saline (NS) group, CS + NS group, NC + lipopolysaccharide (LPS) group, and CS + LPS group. Open field, elevated plus maze, fear conditioning, novel object recognition, and forced swimming tests were performed, and their tissues were harvested. During the second set of experiments, after rearing the mice under the above conditions for 3 weeks, microelectrodes were implanted into the CA1 of the hippocampus. After recovery for 1 week under the respective environmental conditions, the mice were allocated to four groups, as in the first experiments. The basal (home cage) and task (fear conditioning)-related local field potential (LFP) were recorded. In the present study, LPS significantly induced a decrease in the freezing to context and discrimination ratio. However, only the freezing to context was further reduced by prior chronic stress. This suggested that chronic stress worsened fear memory impairment induced by acute LPS challenge. Consistent with the change in fear memory, LPS significantly decreased the expression of PV in the CA1, which was further downregulated by prior chronic stress. On the other hand, LPS inhibited the power of both basal and task-related θ oscillations in the CA1. Only the task-related θ power was further decreased by chronic stress. In conclusion, our study showed that the phenotypic loss of PV interneurons and the decrease in the power of the θ oscillation in the CA1 aggravated by chronic stress may mediate, at least in part, the deterioration of fear memory impairment induced by LPS.

A one-pot hydrothermal synthesis of manganese-doped carbon dots (Mn-CDs) is reported for fluorescent “on-off-on” determination of Mn(VII) and L-ascorbic acid (L-AA) in aqueous solution and living cells. Mn-CDs were prepared by using sulfanilic acid, tetrakis(hydroxymethyl)phosphonium chloride, and Mn(II) chloride as precursors. Mn-CDs were characterized by several spectroscopic methods and microscopic techniques. Mn-CDs show distinctly long fluorescence lifetime (12.39 ± 0.07 ns) and high absolute fluorescence quantum yield (around 37%) with excitation and emission wavelengths of 362 and 500 nm, respectively. Mn-CDs exhibit no significant cytotoxicity to human cervical carcinoma HeLa cells and human embryonic kidney HEK-293T cells at 200 μg mL−1 level after 48 h incubation. The fluorescence of Mn-CDs at 500 nm (excited at 362 nm) is quenched efficiently by Mn(VII) and can be further recovered after the addition of L-AA, resulting in a fluorescent “on-off-on” assay for the determination of Mn(VII) and L-AA. Under optimal experimental conditions, the linear response covers the 3 to 150 μM Mn(VII) concentration range and the 3 to 140 μM L-AA concentration range. This method offers relatively low detection limits of 0.66 μM for Mn(VII) and 0.90 μM for L-AA. This strategy was applied to visual determination of Mn(VII) and L-AA in living HeLa cells with satisfying results.

A ratiometric fluorescent assay is fabricated for the evaluation of alkaline phosphatase (ALP) activity. This assay is composed of ionic liquid–functionalized carbon dots (IL-CDs) with blue fluorescence signal at 470 nm and 2,3-diaminophenazine (DAP) with yellow fluorescence signal at 570 nm. IL-CDs were synthesized via electrochemical method by using ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) and ultrapure water as precursors. DAP is produced by the oxidation reaction between o-phenylenediamine and H2O2 under the catalysis of horseradish peroxidase. H2O2 is reduced by ascorbic acid which is the hydrolysis product of ascorbic acid 2-phosphate under the catalysis of ALP, finally reducing the amount of DAP. The activity of ALP is evaluated through the ratiometric fluorescent signal between IL-CDs and DAP via Forster resonance energy transfer. Under optimal experimental conditions, this ratiometric fluorescent assay has a response that covers the 0.04 to 3.2 U L−1 (12 to 960 pM) ALP activity. This assay possesses ultralow detection limit of 0.012 U L−1 (3.6 pM) for ALP and high selectivity for ALP among several enzymes. The method was used to measure ALP activity in human serum samples with satisfying results.

Background Postoperative cognitive decline (POCD) is a recognized clinical phenomenon characterized by cognitive impairments in patients following anesthesia and surgery, yet its underlying mechanism remains unclear. Brain-derived neurotrophic factor (BDNF) plays an important role in neuronal plasticity, learning, and memory via activation of TrkB-full length (TrkB-FL) receptors. It has been reported that an abnormal truncation of TrkB mediated by calpain results in dysregulation of BDNF/TrkB signaling and is associated with cognitive impairments in several neurodegenerative disorders. Calpains are Ca2+-dependent proteases, and overactivation of calpain is linked to neuronal death. Since one source of intracellular Ca2+ is N-methyl-d-aspartate receptors (NMDARs) related and the function of NMDARs can be regulated by neuroinflammation, we therefore hypothesized that dysregulation of BDNF/TrkB signaling mediated by NMDAR/Ca2+/calpain might be involved in the pathogenesis of POCD. Methods In the present study, 16-month-old C57BL/6 mice were subjected to exploratory laparotomy with isoflurane anesthesia to establish the POCD animal model. For the interventional study, mice were treated with either NMDAR antagonist memantine or calpain inhibitor MDL-28170. Behavioral tests were performed by open field, Y maze, and fear conditioning tests from 5 to 8 days post-surgery. The levels of Iba-1, GFAP, interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), NMDARs, calpain, BDNF, TrkB, bax, bcl-2, caspase-3, and dendritic spine density were determined in the hippocampus. Results Anesthesia and surgery-induced neuroinflammation overactivated NMDARs and then triggered overactivation of calpain, which subsequently led to the truncation of TrkB-FL, BDNF/TrkB signaling dysregulation, dendritic spine loss, and cell apoptosis, contributing to cognitive impairments in aging mice. These abnormities were prevented by memantine or MDL-28170 treatment. Conclusion Collectively, our study supports the notion that NMDAR/Ca2+/calpain is mechanistically involved in anesthesia and surgery-induced BDNF/TrkB signaling disruption and cognitive impairments in aging mice, which provides one possible therapeutic target for POCD.

Background: Only part of the severe patients with coronavirus disease 2019 (COVID-19) may deteriorate to become critically ill and require aggressive treatments and intensive care. We aim to develop an early-warning system to predict the risk of clinical deterioration in an earlier stage to distinguish the patients with or without potential risks in advance by a systematic, data-driven, and analytical approach in severe patients with COVID-19. Methods: This study was designed as a single-centre, retrospective, observational study for the development and validation of a clinical prediction model. We retrospectively analysed 1,364 COVID-19 patients under severe conditions from 22nd Jan. 2020 to 15th Mar. 2020 in Wuhan Tongji hospital (Wuhan, China). We developed a computational modelling framework including data pre-processing, feature generation and ranking, and LightGBM (Light Gradient Boosting), an ensemble machine learning approach, to construct an early-warning system. We thoroughly examined the top features given by the explainable tool from A total of 226 features and attempted to obtain near-optimal performance with much fewer features. To train the model, all samples are divided into a training set and a test set according to a 4:1 ratio. Findings: Nine physiological indicators from the ranking list were used, namely, the first time SARS-CoV-2 nucleic acid detection result, alanine transaminase, lymphocytes, lactate dehydrogenase, antibodies of IgG, C reactive protein, total protein, myoglobin, and monocytes. The prediction model has been validated with AUC 0.9754, ACC 0.9524, recall 0.8571 and specificity 0.9732 using the nine available clinical markers. Interpretation: The prediction model will be used for identifying patients who are at risk of critical disease in early stage of the disease. Due to the high specificity, patients with low risk of critical disease according to the prediction can be classified and managed appropriately to reduce the investment of medical resources. Funding Statement: The study was conceived, developed, and executed by the authors with no funding and external or commercial support. Declaration of Interests: The authors declare that they have no conflict of interest. Ethics Approval Statement: The Ethics Commission of Wuhan Tongji hospital approved the study.

Two new noroleanane-type triterpenoid saponins, 3β,20α,24-trihydroxy-29-norolean-12-en-28-oic acid 24-O-β-L-fucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranoside (1) and 3β,20α,24-trihydroxy-29-norolean-12-en-28-oic acid 24-O-β-D-glucopyranosyl-(1→2)-[α-L-arabinopyranosyl-(1→3)]-β-D-glucopyranoside (2) were isolated from the stems of Stauntonia chinensis DC., together with three known compounds, brachyantheraoside B2 (3), eupteleasaponin Ⅷ (4) and fargoside B (5). Their structures were elucidated by spectroscopic and chemical methods. The cytotoxic activities of compounds 1 and 2 were evaluated against five human tumor cell lines (HCT-116, HepG2, BGC-823, NCI-H1650, and A2780). Compounds 1 and 2 showed moderate cytotoxic activities toward the tested cell lines with IC50 values ranging from 12.71 to 32.04 μM.

Sepsis impairs learning and memory function, yet marked interindividual variability exists in the degree to which sepsis compromises learning and memory function. Thus, testing resilience versus susceptibility to systemic inflammation induced-memory impairment and the underlying mechanism is needed. In the present study, we firstly used lipopolysaccharide (LPS) to induce memory impairment, and then evaluated cognitive function on days 4-7 after the first LPS challenge. Subjects' scores on both behavioral measures were subjected to a hierarchical cluster analysis, identifying two clusters that differed notably on the Y-maze and fear conditioning tests. This analysis divided these subjects into two groups, one cluster (13 of 34 subjects) displayed impaired working and associative memory, named "Susceptive". The remaining cluster (21 of 34 subjects) showed normal memory, named "Resilient". We have also included another group receiving normal saline to serve as the control group. The three groups underwent a battery of biochemical detections. In addition, we investigated whether the individual differences would disappear between the "Resilient" and "Susceptive" groups by using microglia inhibitor minocycline. We showed that as compared with the "Resilient" or control group, the "Susceptive" group was accompanied by increased tumor necrosis factor-alpha, interleukin-1beta (IL-1β), IL-6, and biomarkers of microglia activation ionized calcium binding adaptor molecule-1 and cluster of differentiation 68. Notably, after decreasing the activation of microglia, the differences in cognitive function between the "Resilient" and "Susceptive" groups disappeared. Collectively, our study suggests that individual differences in the brain are associated with resilience versus susceptibility to LPS-induced memory impairment.

The pollution of Hg2+ is one of the most serious problems to human health due to their high toxicity, mobility, difficulty in degradation and ability of accumulation in ecological systems. Thus, it is of great importance to develop highly selective and sensitive probe for detecting Hg2+ in aquatic ecosystems. Here we propose a new turn-on strategy for specific recognition and detection of Hg2+. Mn-doped ZnSe quantum dots (QDs) with small size (2.1 nm) were prepared and adopted as probe, the small size of doped QDs makes the replacement of Mn2+ by Hg2+ accessible, which eliminates the fluorescence quenching effect of superficial Mn2+ on Mn-doped ZnSe QDs. Different from traditional semiconductor nanocrystals based turn-off probe for detecting Hg2+, we realize a turn-on strategy for the selective detection of Hg2+ by Hg2+-Mn2+ replacement using semiconductor nanocrystals (Mn-doped ZnSe QDs). This turn-on mechanism was verified by fluorescence spectra, ICP-AES and XPS. In the absence of Hg2+, Mn-doped ZnSe QDs possessed low fluorescence intensity. With the addition of Hg2+, the fluorescence intensity around 600 nm increased dramatically. Our Mn-doped ZnSe QDs exhibits excellent selectivity and sensitivity for Hg2+. The limit of detection is 7.0 nM, which is lower than the mercury toxic level defined by the U.S. Environmental Protection Agency (10 nM). The result of Hg2+ detection in real samples indicates the feasibility and sensitivity of our probe for application in environmental samples.

With spreading applications of fluorescent quantum dots (QDs) in biomedical fields in recent years, there is increasing concern over their toxicity. Among various factors, surface ligands play critical roles. Previous studies usually employed QDs with different kinds of surface ligands, but general principles were difficult to be obtained since it was hard to compare these surface ligands with varied chemical structures without common features. Herein, the physicochemical properties of two types of CdTe QDs were kept very similar, but different in the surface ligands with mercaptoacetic acid (TGA) and 3-mercaptopropionic acid (MPA), respectively. These two types of homologous ligands only had a difference in one methylene group (–CH2–). The interactions of the two types of CdTe QDs with bovine serum albumin (BSA), which was one of the main components of cell culture, were studied by fluorescence, UV-vis absorption, and circular dichroism spectroscopy. It was found that the fluorescence quenching of BSA by CdTe QDs followed a static quenching mechanism, and there was no obvious difference in the Stern–Volmer quenching constants and binding constants. The thermodynamic parameters of the two types of QDs were similar. BSA underwent conformational changes upon association with these QDs. By comparing the cytotoxicity of these two types of QDs, TGA-capped QDs were found to be less cytotoxic than MPA-capped QDs. Besides, in the presence of serum proteins, the cytotoxicity of the QDs was reduced. QDs in the absence of serum proteins had a higher internalization efficiency, compared with those in the medium with serum. To the best of our knowledge, this is a rare study focusing on surface ligands with such small variations at the biomolecular and cellular levels. These findings can provide new insights for the design and applications of QDs in complex biological media.

Effect of pine needle extract from Cedrus deodara (PNE) on the quality and safety of Chinese traditional smoked bacon was observed, and its action mechanism was further investigated. With the treatment of PNE, the quality properties of smoked bacon, including moisture content, pH and titratable acidity values, color, texture and volatile compositions, were all ameliorated. Meanwhile, the peroxide value (POV), thiobarbituric acid value (TBARS) and nitrite content of smoked bacon with PNE decreased. In addition, the content of N-nitrosodimethylamine in smoked bacon gradually decreased with the increased concentration of PNE. Moreover, the heavy polycyclic aromatic hydrocarbons (PAHs) were not detected in smoked bacon with PNE, while the types and contents of light PAHs in smoked bacon were both reduced by PNE. With the measurement of fluorescence spectroscopy and circular dichroism spectroscopy, the secondary and tertiary structures of myofibrillar protein in smoked bacon were both changed though the treatment of PNE. Furthermore, according to the analysis of molecular docking, hydrogen bond was the main molecular force between PNE and meat proteins in smoked bacon. All present results suggested that PNE had the potential value to improve the quality and safety of smoked bacon in food industry.

Fullerenols, known as polyhydroxylated derivatives of fullerene, have attracted great attention due to their distinctive material properties and potential applications in biology and medicine. As a step toward the elucidation of basic behavior in biological systems, a variety of spectroscopic measurements as well as isothermal titration calorimetry (ITC) were applied to study the interaction between fullerenol (C60(OH)44) and serum proteins (bovine serum albumin (BSA) and γ-globulins). The results of fluorescence spectra indicated that the intrinsic fluorescence of proteins could be effectively quenched by the dynamic mechanism. The affinity values of both proteins bound to fullerenol were of the same order of magnitude. Meanwhile, ITC results showed that the interaction between fullerenol and BSA was enthalpy favorable, while the interaction with γ-globulins was enthalpy unfavorable. Furthermore, fullerenol had little influence on the secondary structure of both proteins. Additional cytotoxicity tests showed that the presence of proteins attenuated the toxic effect of fullerenol on human normal gastric epithelial cell line (GES-1). Thus, the interaction between fullerenol and proteins is indispensable to evaluate the biosafety of fullerenol, which may in turn promotes the development of its biological applications.

China is being transformed by economic development, urban migration, and social change. Environmental reporting on China has tended to focus on environment damage, especially air pollution. Relatively unnoticed in the West, however, China has invested in improving and expanding its system of protected areas. These protected areas follow varied models—they include nature reserves, forest parks, wetland parks, and more—and face challenges roughly similar to those of protected areas in the United States and many other countries. Unsurprisingly, though, there are important differences that make China's protected area program uniquely Chinese. Chinese protected areas have been largely created and continue to be developed with strong top-down authority, although national-level control is softening and other models are being tested. Several nature reserves have received influxes of government funding in recent years to improve and expand their infrastructure and activities to support conservation, tourism, and other uses. Chinese nature reserves also tend to have explicit zoning and economic activities designed to promote economic development in and around them; this emphasis on economic development is greater and takes a different approach in Chinese parks than is typical in Western park systems. Here we compare aspects of the Chinese and US investments in national parks and national nature reserves; we use two examples—Wudalianchi National Nature Reserve in China and Acadia National Park in the United States—to highlight similarities and differences. We conclude that each country's approach to protected areas has strengths and weaknesses in terms of conservation value, engagement with local communities, and sustainability, but that overall each country's protected areas program has structural deficiencies, particularly related to the allocation of funding, that undermine their ability to achieve their stated mission over the long term. The shortcomings in each country are different and may not be as substantial as the shortcomings of` national parks in many other countries, but they are critical nonetheless.

The interaction mechanism of multiple quaternary ammonium salts (MQAS) with bovine serum albumin (BSA) was examined by the fluorescence quenching method and circular dichroism (CD) spectra. Moreover, the effects of MQAS on the dynamic properties of BSA adsorption layers at different pH values were investigated using dilational interfacial rheology. Results show that the quenching constants increase with an increase in pH values and decrease with an increase in the experiment temperature at pH 5.3. The quenching mechanism is static quenching, and the electrostatic force dominates the interaction between MQAS and BSA at pH 5.3. Due to three positive head groups, MQAS can significantly affect the dynamic interfacial activity of BSA molecules at a relatively low concentration. At pH 4.3, the electrostatic repulsion is unfavorable for the formation of MQAS/BSA complexes. Consequently, MQAS molecules will replace BSA molecules from the interface by competitive adsorption. At the pH value above the isoelectric point of BSA, the electrostatic attraction is better for the formation of MQAS/BSA complexes, which exhibit a rapid adsorption rate and an enhanced interfacial activity. Moreover, the kinetic dependencies of interfacial dilational elasticity for the MQAS/BSA mixtures become nonmonotonous. The appearance of the maximum interfacial elasticity values can be attributed to the formation of tails and loops, which suggests that the addition of MQAS destroys the secondary and tertiary structure of protein in the bulk phase. In addition, the effects of MQAS on the secondary structure of protein were demonstrated by CD spectra.

Understory vegetation hosts high biodiversity and plays a critical role in the ecosystem processes of boreal forests. However, the drivers of understory plant diversity in this high-latitude ecosystem remain uncertain. To investigate the influences of forest type and latitude on understory beta diversity at different scales, we quantified the species composition of Vaccinium uliginosum Linnaeus communities under broadleaf and coniferous forests at two latitudes at the quadrat (2 &times, 2 m) and plot (10 &times, 10 m) scales in the Greater Xing&rsquo, an Mountains, NE China. At the quadrat scale, species alpha diversity of V. uliginosum communities was higher in broadleaf forests than that in coniferous forests at both latitudes. The differences in species beta diversity (the S&oslash, rensen&rsquo, s dissimilarity) in two forest types depended on the latitude: beta diversity in broadleaf forests was higher than that in coniferous forests at the higher latitude, while beta diversity in coniferous forests was higher at the lower latitude. At the plot scale, alpha and beta diversity of V. uliginosum communities decreased from broadleaf forests to coniferous forests at the higher latitude, and they did not show significant differences between forest types at the lower latitude. These results indicate the interactive effects of forest type and latitude on beta diversity of understory vegetation. Moreover, the influences of forest type and latitude on species alpha and beta diversity were different across the two spatial scales, suggesting that the assembly mechanisms underlying species diversity may be different at different scales. Understanding the maintenance of understory vegetation diversity will benefit the conservation and management of boreal forests.

Herein, binding interaction between black phosphorus quantum dots (BPQDs) and human serum albumin (HSA) was systematically characterized for deep illustration of conformational structure variation of HSA affected by BPQDs. The results confirmed that the intrinsic fluorescence of HSA was statically quenched by BPQDs mainly through van der Waals interaction and hydrogen bond. BPQDs bound strongly with the site I of HSA to form ground state complex with molar ratio of 1 to 1. The secondary structure of HSA was changed obviously after its binding interaction with BPQDs, and the α-helix structure of HSA was transformed to the β-sheet structure. The melting temperature of HSA was decreased after its binding interaction with BPQDs, suggesting that BPQDs promoted the thermal denaturation process of HSA. BPQDs could also reduce the molar enthalpy change and the thermal stability of HSA. These results explored the exact conformational structure variation of HSA after its binding interaction with BPQDs, which provides vital information for possible biological influence of BPQDs on human beings.

Rheumatoid arthritis( RA) is an autoimmune disease characterized by chronic and aggressive polyarthritis. The innate immunity mechanism plays a key role in the pathogenesis of RA. Tripterygium wilfordii and its extracts have regulatory effects on innate immune cells including macrophages,dendritic cells,neutrophils,mast cells,NK cells,NKT cells,etc.,as well as a variety of innate immune molecules including cytokines,adhesion molecules,patterns recognition receptor( PRR) and the complement molecules,showing a regulatory effect in the pathogenesis of RA innate immunity. In this paper,the recent domestic and foreign researches on the pathogenesis of RA with innate immunity involved were reviewed and the research status of T. wilfordii and its extracts on the regulation of innate immunity involved in RA was summarized.

To explore the optimum conditions for the extraction of anthocyanins and flavonols from bog bilberry (Vaccinium uliginosum L.) marc on a single-factor experimental basis, a response surface methodology was adopted for this intensive study. The extraction procedure was carried out in a Waring blender and followed an ultrasonic bath, and the natural antioxidant carnosic acid was added to inhibit oxidation. The optimum extraction conditions were as follows: a volume fraction of ethanol of 70%, an antioxidant content of 0.02% (the mass of sample) carnosic acid, a liquid&ndash, solid ratio of 16 mL/g, a homogenization time of 3 min, a reaction temperature of 55 &deg, C, an ultrasound irradiation frequency of 80 kHz, an ultrasound irradiation power of 200 W, and an ultrasound irradiation time of 40 min. Satisfactory yields of anthocyanins (13.95 &plusmn, 0.37 mg/g) and flavonols (3.51 &plusmn, 0.16 mg/g) were obtained. The experimental results showed that the carnosic acid played an effective antioxidant role in the extraction process of anthocyanins and flavonols with a green and safety guarantee.

Sepsis-associated encephalopathy induces cognitive dysfunction via mechanisms that commonly involve neuroinflammation and synaptic plasticity impairment of the hippocampus. The β2-adrenoceptor (β2-AR) is a G-protein coupled receptor that regulates immune response and synaptic plasticity, whereas its dysfunction has been implicated in various neurodegenerative diseases. Thus, we hypothesized abnormal β2-AR signaling is involved in sepsis-induced cognitive impairment. In the present study, C57BL/6 mice were subjected to cecal ligation and puncture (CLP) to mimic the clinical human sepsis-associated encephalopathy. The levels of hippocampal β2-AR, proinflammatory cytokines tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), IL-6, cAMP-response element binding protein (CREB), brain derived neurotrophic factor (BDNF), post-synaptic density protein 95 (PSD95), and NMDA receptor 2 B subtypes (GluN2B) were determined at 6, 12, 24 h and 7 and 16 days after CLP. For the interventional study, mice were treated with β2-AR agonist clenbuterol in two ways: early treatment (immediately following CLP) and delayed treatment (on the 8th day following CLP). Neurobehavioral performances were assessed by open field and fear conditioning tests. Here, we found that hippocampal β2-AR expression was significantly decreased starting from 12 h and persisted until 16 days following CLP. Besides, sepsis mice also exhibited increasing neuroinflammation, down-regulated CREB/BDNF, decreasing PSD95 and GluN2B expression, and displayed hippocampus-dependent cognitive impairments. Notably, early clenbuterol treatment alleviated sepsis-induced cognitive deficits by polarizing microglia toward an anti-inflammatory phenotype, reducing proinflammatory cytokines including IL-1β, TNF-α, and up-regulating CREB/BDNF, PSD95, and GluN2B. Intriguingly, delayed clenbuterol treatment also improved cognitive impairments by normalization of hippocampal CREB/BDNF, PSD95, and GluN2B. In summary, our results support the beneficial effects of both early and delayed clenbuterol treatment, which suggests that activation of β2-AR has a translational value in sepsis-associated organ dysfunction including cognitive impairments.

Developing simple and sensitive non-aggregation strategy for detecting Cd

Two new norneolignans, (7

Sepsis-associated encephalopathy (SAE) is a potentially irreversible acute cognitive dysfunction with unclear mechanism. Striatal-enriched protein tyrosine phosphatase (STEP) is a brain-specific phosphatase which normally opposes synaptic strengthening by regulating key signaling molecules involved in synaptic plasticity and neuronal function. Thus, we hypothesized that abnormal STEP signaling pathway was involved in sepsis-induced cognitive impairment evoked by lipopolysaccharides (LPS) injection. The levels of STEP, phosphorylation of GluN2B (pGluN2B), the kinases extracellular signal-regulated kinase 1/2 (pERK), cAMP-response element binding protein (CREB), synaptophysin, brain derived neurotrophic factor (BDNF), and post-synaptic density protein 95 (PSD95) in the hippocampus, prefrontal cortex, and striatum were determined at the indicated time points. In the present study, we found that STEP levels were significantly increased in the hippocampus, prefrontal cortex, and striatum following LPS injection, which might resulted from the disruption of the ubiquitin-proteasome system. Notably, a STEP inhibitor TC-2153 treatment alleviated sepsis-induced memory impairment by increasing phosphorylation of GluN2B and ERK1/2, CREB/BDNF, and PSD95. In summary, our results support the key role of STEP in sepsis-induced memory impairment in a mouse model of SAE, whereas inhibition of STEP may provide a novel therapeutic approach for this disorder and possible other neurodegenerative diseases.

Microglia activation and subsequent pro-inflammatory responses play a key role in the development of neuropathic pain. The process of microglia polarization towards pro-inflammatory phenotype often occurs during neuroinflammation. Recent studies have demonstrated an active role for the gut microbiota in promoting microglial full maturation and inflammatory capabilities via the production of Short-Chain Fatty Acids (SCFAs). However, it remains unclear whether SCFAs is involved in pro-inflammatory/anti-inflammatory phenotypes microglia polarization in the neuropathic pain. In the present study, chronic constriction injury (CCI) was used to induce neuropathic pain in mice, the mechanical withdrawal threshold, thermal hyperalgesia were accomplished. The levels of microglia markers including ionized calcium-binding adaptor molecule 1 (Iba1), cluster of differentiation 11b (CD11b), pro-inflammatory phenotype markers including CD68, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and anti-inflammatory phenotype markers including CD206, IL-4 in the hippocampus and spinal cord were determined on day 21 after CCI. The results showed that CCI produced mechanical allodynia and thermal hyperalgesia, and also increased the expressions of microglia markers (Iba1, CD11b) and pro-inflammatory phenotype markers (CD68, IL-1β, and TNF-α), but not anti-inflammatory phenotype marker (CD206, IL-4) in the hippocampus and spinal cord, accompanied by increased SCFAs in the gut. Notably, antibiotic administration reversed these abnormalities, and its effects was also bloked by SCFAs administration. In conclusion, data from our study suggest that CCI can lead to mechanical and thermal hyperalgesia, while SCFAs play a key role in the pathogenesis of neuropathic pain by regulating microglial activation and subsequent pro-inflammatory phenotype polarization. Antibiotic administration may be a new treatment for neuropathic pain by reducing the production of SCFAs and further inhibiting the process of microglia polarization.