Potentiation of the lateral habenula-ventral tegmental area pathway underlines the susceptibility to depression in mice with chronic pain.

Chronic pain often develops severe mood changes such as depression. However, how chronic pain leads to depression remains elusive and the mechanisms determining individuals' responses to depression are largely unexplored. Here we found that depression-like behaviors could only be observed in 67.9% of mice with chronic neuropathic pain, leaving 32.1% of mice with depression resilience. We determined that the spike discharges of the ventral tegmental area (VTA)-projecting lateral habenula (LHb) glutamatergic (Glu) neurons were sequentially increased in sham, resilient and susceptible mice, which consequently inhibited VTA dopaminergic (DA) neurons through a LHbGlu-VTAGABA-VTADA circuit. Furthermore, the LHbGlu-VTADA excitatory inputs were dampened via GABAB receptors in a pre-synaptic manner. Regulation of LHb-VTA pathway largely affected the development of depressive symptoms caused by chronic pain. Our study thus identifies a pivotal role of the LHb-VTA pathway in coupling chronic pain with depression and highlights the activity-dependent contribution of LHbGlu-to-VTADA inhibition in depressive behavioral regulation.

[Characteristics of climate change and its impacts on water resources in Qilian Mountains, China]. / ç¥è¿žå±±æ°”å€™å˜åŒ–ç‰¹å¾åŠå ¶å¯¹æ°´èµ„æºçš„å½±å“.

Qilian Mountains, is an important ecological function area, an important ecological security barrier, the river runoff region in Northwest China, as well as a sensitive area to global climate change and fragile area of ecological environment. The ecological environment in this area played an important role in the economic development of Northwest China. Based on the observation data of temperature and precipitation in Qilian Mountains, MOD10A2 snow products and the flow data of Shiyang River, Heihe River and Shule River, we systematically analyzed the characteristics of climate change from 1961 to 2020, and the impacts of climate change on water resources under the scenario of climate warming. The results showed that, from 1961 to 2020, the annual average temperature increased significantly, with the rate reaching 0.39 ℃·(10 a)-1. The warming rate was the highest in the western part of Qilian Mountains, followed by the middle and eastern regions. The warming trend was the strongest in winter and the lowest in spring. The average temperature changed abruptly in 1997. The annual average precipitation increased with flucturation, with a rate of 10 mm·(10 a)-1, which increased most obviously in the middle of Qilian Mountains. After 2004, it entered a rainy period, with a warm and humid trend. The precipitation in the four seasons showed an increasing trend and the increase of precipitation in summer contributed the most to the annual precipitation. Annual precipitation was dominated by interannual scale change, and the contribution rate of 2.8-year was approximately 64.3%. The snow cover of Qilian Mountains was obviously affected by temperature and snowfall, which was negatively correlated with summer temperature and positively correlated with snowfall. From 2016 to 2020, the temperature increase had slowed down in Qilian Mountains, the snowfall had increased, and the snow cover tended to increase. After 2000, the temperature and precipitation increased more obviously, the meltwater from glacier and snow increased, the mountainous runoff of Shiyang River, Heihe River and Shule River had an increasing trend. Our findings are of great significance to the construction of ecological civilization and coping with climate change in Qilian Mountains.

A novel light-controlled colorimetric detection assay for nitroreductase based on p-aminophenol-catalyzed and NADH-mediated synthesis of silver nanoparticles.

A novel and efficient light-controlled colorimetric assay for the quantification and detection of nitroreductase (NTR) was constructed based on p-aminophenol (pAP)-catalyzed and nicotinamide adenine dinucleotide (NADH)-mediated generation of AgNPs. Due to the hydrolysis of p-nitrophenol by NTR in the presence of NADH, the hydrolysis product can be used as a catalyst to catalyze the reduction of Ag+ by NADH under the light. As the concentration of NTR increases, the value of absorbance at ca. 400 nm (A400) decreases and the color of the solution turns from brown to bright yellow. A linear correlation was obtained between A400 and the NTR concentration in the range from 1-50 µg mL-1 and the limit of detection (LOD) is 0.27 µg mL-1. The detection system does not respond to other common biological molecules due to the specificity of enzymes and the effect of the nitroreductase inhibitor on the NTR activity was also tested. Finally, we applied the assay to determine NTR in human serum samples by spiking different concentrations of NTR with a recovery of 85.2%-92.5%.

Smartphone colorimetric assay of acid phosphatase based on a controlled iodine-mediated etching of gold nanorods.

A simple but efficient colorimetric assay was developed for the detection and quantification of acid phosphatase (ACP) using a smartphone. This strategy is based on target-controlled iodine-mediated etching of gold nanorods (AuNRs). Due to effective hydrolysis of the substrate pyrophosphate (PPi) by ACP, chelated Cu2+ with PPi was released, which promoted the redox reaction with an iodide ion (I-), leading to the formation of I3-. As the etching agent of AuNRs, I3- caused a blueshift of the localized surface plasmon resonance peak and, more importantly, an observable color change. The vivid colors were recorded with a smartphone camera and directly analyzed using an image-processing app. On the basis of the direct correlation between ACP concentration and the etching degree of AuNRs as well as color change, this smartphone nanocolorimetry technique showed a good linear response toward ACP over the range of 0-15.0 U/L, with a detection limit of 0.97 U/L. Using the standard addition method, the practical applicability of the proposed smartphone-based assay was successfully demonstrated by determining ACP in human serum samples, with results consistent with those obtained by UV-Vis spectrophotometry.

In vitro genotoxicity study of silver nanoparticles and titanium dioxide nanoparticles.

Nanoparticles are widely used in cosmetic, pharmaceutical, and food industries, but their safety and genetic toxicity are still unclear. In this study, the genotoxicity of silver nanoparticles (AgNPs) and titanium dioxide nanoparticles (titanium dioxide nanoparticles) were evaluated by in vitro comet assay and PIG-A assay in TK6 cells. We exposed TK6 cells to two types of nanoparticles at the highest concentration of 200 µmol/L for 4 h and conducted the in vitro comet assay. We examined the mutation results of PIG-A gene in vitro after 4 h, 24 ho and 10 days of exposure, respectively. We also examined the endocytosis of nanoparticles in TK6 cells exposed to nanoparticles for 24 h. In the endocytosis assay, with the increase of nano-material concentration, the side scatter (SSC) of TK6 cells in flow cytometry showed a concentration-dependent and time-dependent increase, indicating that TK6 cells could uptake both types of nanoparticles. In the comet assay, AgNPs could induce a concentration-dependent increase in DNA tail intensity. However, titanium dioxide NPs could not induce the concentration-dependent increase of DNA fluorescence intensity of comet tail. In the PIG-A assay, both AgNPs and TiO2NPs did not induce PIG-A gene mutation frequency in TK6 cells. The results showed that AgNPs could induce DNA damage in TK6 cells, but could not induce increase of PIG-A gene mutation frequency. TiO2NPs neither induce DNA damage in TK6 cells nor increase PIG-A mutation frequency. Further tests are needed to determine whether TiO2NPs are genotoxic.

Colorimetric determination of cytosine-rich ssDNA by silver(I)-modulated glucose oxidase-catalyzed growth of gold nanoparticles.

A colorimetric assay is described for determination of cytosine-rich ssDNA at physiological pH values. The working principle is based on (a) Ag(I) ion-induced formation of an i-motif structure, and (b) glucose oxidase-controlled growth of gold nanoparticles (AuNPs). The combination between Ag+ and cytosine-rich DNA can modulate the generation of H2O2 resulting from enzyme catalyzed glucose oxidation. Depending on the amount of H2O2 formed, the solution containing the AuNPs will turn red in the presence of cytosine-rich ssDNA but blue in the absence of such DNA if Ag+ is added before the formation of the red AuNPs. Upon addition of C-DNA at different concentrations, the peak shift (Δλ) of the AuNP solution relative to the SPR peak position (560 nm) in the absence of C-DNA is taken as the signal readout. The method shows a good linear response toward C-DNA over the range 10-200 nM with a detection limit of 2.7 nM. It may also be performed visually. The photometric assay is highly sensitive, specific, and rapid. The method is particularly attractive in terms of applications such as in human serum analysis, a colorimetric logic gate, and the calculation of binding constants for the interaction between Ag+ and glucose oxidase (GOx), and between Ag+ and cytosine-rich ssDNAs. Graphical abstract Schematic presentation of colorimetric detection of cytosine (C)-rich ssDNA (C-DNA) based on the modulation of the glucose oxidase (GOx)-catalyzed growth of gold nanoparticles (AuNPs) with Ag+ as the enzyme inhibitor.

Security protection using two different image shadows with authentication.

Security protection using two different image shadows with authentication.

A highly sensitive fluorescent probe with different responses to Cu2+ and Zn2.

We report a highly sensitive fluorescent probe based on p-dimethylaminobenzoyl derivatives (probe L) for the detection of Cu2+ and Zn2+. In this work, the probe L exhibited a fluorescent turn-on sensing model to Cu2+ and Zn2+ with a distinct fluorescent color change from colorless to green and yellow respectively. Probe L exhibited high selectivity as a fluorescent Cu2+/Zn2+ probe with a limit of detection (LOD) of 45 nM/17 nM. The results of 1H NMR titrations revealed that the response of L to Cu2+ and Zn2+ was triggered by the interaction of the thiophene unit and the metal ion. Furthermore, the fluorescence titrations and Job's plot curves displayed the binding ratio of 1:2 for Cu2+ and 1:1 for Zn2+ metal-L complex formation respectively. Density functional theory calculation also demonstrated the possibility of molecular luminescence and the process of metal-L complex formation. Additionally, fluorescent test strips have been prepared for convenient detection of Cu2+ and Zn2+, which means the convenient and rapid assay in real samples can be achieved.

A novel jointly colorimetric and fluorescent sensor for Cu2+ recognition and its complex for sensing S2- by a Cu2+ displacement approach in aqueous media.

In this work, a simple and easily synthesized Schiff-based derivative colorimetric and fluorescent sensor (1), 4-dimethylamino-benzoic acid (2-imidazole formaldehyde)-hydrazide, was obtained for the detection of Cu2+ and S2-. The compound 1 exhibited dual spectral responses to Cu2+, that is, vivid color change and fluorescence enhancement in the presence of Cu2+. The detection limits were valued as 0.46 µM and 15 nM according to absorption and fluorescent response, respectively. Both of them are below the World Health Organization (WHO) guidelines for drinking water (31.5 µM). In addition, the ensemble (1-Cu2+) selectively and sensitively detected a low concentration of S2-. As the addition of S2- instantly removed Cu2+ from the ensemble (1-Cu2+) resulting in a color change from yellow to colorless and a "turn-off" fluorescent response. The detection limit for S2- was estimated as 0.12 µM (from fluorescent method) and 0.68 µM (from absorption method), respectively, each of which was also lower than the maximum allowable level of S2- (15 µM) in drinking water defined by the WHO. The binding process was confirmed via UV-vis absorption, fluorescence measurements, 1H NMR, mass spectroscopy and density functional theory calculation. What's more, successful practical application of test paper is used to inspect the S2- which means the convenient and rapid assay in real samples can be achieved.

A highly selective turn-on fluorescent probe for Al3+ in aqueous solution based on quinoline Schiff-base.

A new Al3+-specific fluorescent probe NQ was designed and synthesized from 2-hydroxy-1-naphthaldehyde and 2-aminoquinoline. Upon the addition of Al3+, the fluorescent intensity of NQ was significantly enhanced compared with other examined metal ions in aqueous solution. The result of a Job's plot indicated the formation of a 1:1 complex between the probe and Al3+, and the possible binding mode of the system between NQ and Al3+ was clarified by IR analysis and 1H NMR titration. Moreover, other metal ions examined had little effect on the detection of Al3+. The detection limit of NQ for Al3+ detection was 1.98 µM, which is lower than the level (7.4 µM) in drinking water defined by the World Health Organization. In addition, the fluorescent probe NQ could be recyclable simply through treatment with a proper reagent such as F-, and could also be used for the detection of Al3+ in real samples.

Ultrasensitive turn-on fluorescence detection of Cu2+ based on p-dimethylaminobenzamide derivative and the application to cell imaging.

A new p-dimethylaminobenzamide derivative based compound BDIH has been synthesized. Cu2+ turned on the fluorescence of compound BDIH with a 1:2 binding stoichiometry. The fluorescent color of compound BDIH shows an evident change from colorless to bright blue upon the addition of Cu2+, which could be visibly detected by the naked eye under UV light at 365nm. More importantly, the detection limit was found to be 0.64nM which is far lower than the maximal allowed concentration of the WHO limit (31.5µM) for drinking water. This selective "turn-on" fluorescence sensor was used to identify Cu2+ in living cells using confocal fluorescence microscopy, indicating that compound BDIH has a potential application for selective detection of Cu2+ in organism.

Note: Durability analysis of optical fiber hydrogen sensor based on Pd-Y alloy film.

The Pd-Y alloy sensing film has an excellent property for hydrogen detection, but just for one month, the sensing film's property decreases seriously. To study the failure of the sensing film, the XPS spectra analysis was used to explore the chemical content of the Pd-Y alloy film, and analysis results demonstrate that the yttrium was oxidized. The paper presented that such an oxidized process was the potential reason of the failure of the sensing film. By understanding the reason of the failure of the sensing film better, we could improve the manufacturing process to enhance the property of hydrogen sensor.

[Condylar position and condylar symmetry in patients with temporomandibular disorders].

PURPOSE: To investigate condylar position and condylar symmetry in patients with temporomandibular disorders (TMD) as well as malocclusion. METHODS: Fifteen patients with TMD and malocclusion were selected for the experiment, 15 asymptomatic patients served as controls. The bilateral temporomandibular joints of all subjects were evaluated by computed tomography (CT) imaging. Both the joint spaces and the condylar symmetry were determined, based on the axial CT images properly chose. All statistical analysis were performed using SPSS17.0 software package. RESULTS: The condyle of the patients in the experimental group were seated more posteriorly, while slight anterior condylar position were found in the control group. In the experimental group, the horizontal angle of the condyle in the symptomatic side was larger than that in the asymptomatic side (P<0.05), while the vertical angle was just opposite (P<0.05). No statistically significant asymmetries were found in the mediolateral diameter,the anteroposterior diameter, the angle of condylar axis, the distance between condylar center to midsagittal plane and anteroposterior difference of condyle center. CONCLUSION: Obvious posterior condylar position and vertical asymmetry exist in patients with temporomandibular disorders.