De Novo Design of a Highly Stable Ratiometric Probe for Long-Term Continuous Imaging of Endogenous HClO Burst.

Long-term continuous imaging of endogenous HClO burst is of great importance for the elucidation of various physiological or pathological processes. However, most of the currently reported HClO probes have failed to achieve this goal due to their insufficient photobleaching resistance under a laser source. Herein, a highly stable ratiometric probe, HFTC-HClO 1, which is capable of continuously monitoring endogenous HClO burst over a long period of time, has been judiciously developed. Briefly, the de novo development of HFTC-HClO 1 mainly involved three main steps: (1) novel coumarins (HFTC 1-5) were designed and synthesized; (2) the most stable scaffold, HFTC 3, was selected through dye screening and cell imaging validation; and (3) based on HFTC 3, three candidate HClO probes were constructed, and HFTC-HClO 1 was finally selected due to its superior sensing properties toward HClO. Furthermore, HFTC-HClO 1 can quantitatively measure HClO levels in various real samples with excellent recovery (>90.4%), and the use of HFTC-HClO 1-coated test strips for qualitative analysis of HClO in real samples was also achieved. In addition, the application of HFTC-HClO 1 for long-term continuous monitoring of intracellular HClO burst was successfully demonstrated. Significantly, HFTC-HClO 1 was able to visualize HClO generated in the rheumatoid arthritis mouse model.

Functional MRI of inhibitory control processing in problematic mobile video gamers.

With the development of mobile technology, mobile video games provide people with a more convenient way of entertainment, but problematic playing could also bring some negative consequences. Prior studies have indicated that Internet gaming addicts were accompanied by impaired inhibitory control. However, as a relatively new form of problematic game usage based on mobile devices, little is known about the neurobiological underpinnings of inhibitory control in problematic mobile video game (PMVG) users. Adopting an event-related fMRI Stroop task, the present study aimed to examine the different neural correlates of inhibitory control between PMVG and healthy control (HC) subjects. Compared with HC group, PMVG group showed greater brain activities in the right dorsolateral prefrontal cortex (DLPFC) during the Stroop process. Moreover, correlation analysis showed that brain activities extracted from the voxel in the DLPFC cluster had a significantly negative correlation with reward sensitivity. Our current findings may suggest the compensating effect in key brain regions of inhibitory control in problematic mobile video gamers relative to healthy controls.

Homoadamantane-Fused Tetrahydroquinoxaline as a Robust Electron-Donating Unit for High-Performance Asymmetric NIR Rhodamine Development.

Rhodamines have emerged as a useful class of dye for bioimaging. However, intrinsic issues such as short emission wavelengths and small Stokes shifts limit their widespread applications in living systems. By taking advantage of the homoadamantane-fused tetrahydroquinoxaline (HFT) moiety as an electron donor, we developed a new class of asymmetric NIR rhodamine dyes, NNR1-7. These new dyes retained ideal photophysical properties from the classical rhodamine scaffold and showed large Stokes shifts (>80 nm) with improved chemo/photostability. We found that NNR1-7 specifically target cellular mitochondria with superior photobleaching resistance and improved tolerance for cell fixation compared to commercial mitochondria trackers. Based on NNR4, a novel NIR pH sensor (NNR4M) was also constructed and successfully applied for real-time monitoring of variations in lysosomal pH. We envision this design strategy would find broad applications in the development of highly stable NIR dyes with a large Stokes shift.

Genome-Wide Identification of the Bcl-2 Associated Athanogene (BAG) Gene Family in Solanum lycopersicum and the Functional Role of SlBAG9 in Response to Osmotic Stress.

The Bcl-2-associated athanogene (BAG) proteins are a family of multi-functional group of co-chaperones regulators, modulating diverse processes from plant growth and development to stress response. Here, 10 members of SlBAG gene family were identified based on the available tomato (Solanum lycopersicum) genomic information and named as SlBAG1-10 according to their chromosomal location. All SlBAG proteins harbor a characteristic BAG domain, categorized into two groups, and SlBAG4, SlBAG7, and SlBAG9 of group I contain a plant-specific isoleucine glutamine (IQ) calmodulin-binding motif located in the N terminus. The quantitative real-time PCR expression analysis revealed that these SlBAG genes had organ-specific expression patterns and most SlBAG genes were differentially expressed in multiple abiotic stresses including drought, salt, high temperature, cold, and cadmium stress as well as abscisic acid and H2O2. In addition, heterologous overexpression of SlBAG9 increased the sensitivity of Arabidopsis to drought, salt, and ABA during seed germination and seedling growth. The decreased tolerance may be due to the downregulation of stress-related genes expression and severe oxidative stress. The expression levels of some stress and ABA-related genes, such as ABI3, RD29A, DREB2A, and P5CS1, were significantly inhibited by SlBAG9 overexpression under osmotic stress. Meanwhile, the overexpression of SlBAG9 inhibited the expression of FSD1 and CAT1 under stress conditions and the decreased levels of superoxide dismutase and catalase enzyme activities were detected accompanying the trends in the expression of both genes, which resulted in H2O2 accumulation and lipid peroxidation. Taken together, these findings lay a foundation for the future study of the biological function of SlBAG genes in tomato.

Overexpression of a Bcl-2-associated athanogene SlBAG9 negatively regulates high-temperature response in tomato.

The Bcl-2-associated athanogene (BAG) gene is a multi-functional family of co-chaperones regulator, modulating plant stress response. Our previous study revealed that the SlBAG9 of tomato (Solanum lycopersicum) had the higher expression level induced by high-temperature (HT) at the transcriptional and protein levels, but its biological function was still unclear. Here, we conducted an in-depth analysis of SlBAG9. SlBAG9 protein was not located in the mitochondria but in the cytoplasm and nucleus. Many cis-acting elements involved in plant stress and hormone responses were located in the promoter regions of SlBAG9 including heat-shock element (HSE1). The ß-glucuronidase (GUS) histochemical analysis showed that SlBAG9 promoter could drive GUS gene expression in transiently transformed Nicotiana tabacum leaves under non-inducing condition and HSE1 is critical for HT-induced GUS activity under HT. The transcription of SlBAG9 was expressed in different organs and was regulated by HT, cold, drought, and salt stresses as well as exogenous abscisic acid (ABA) and H2O2. To further elucidate SlBAG9 function in response to HT, the transgenic tomato plants overexpressing SlBAG9 were developed. Compared to the wild-type plants, SlBAG9-overexpressing plants exhibited more sensitivity to HT stress, reflected by the burning symptoms, the degradation of chlorophyll, and the reduction of photosynthetic rates. Additionally, SlBAG9-overexpressing lines showed higher accumulation of lipid peroxidation production (MDA) and H2O2, but lower activities of superoxide dismutase, catalase, and peroxidase. Therefore, it is speculated that SlBAG9 plays a negative role in thermotolerance probably by inhibition of antioxidant enzyme system leading to the oxidative damage, consequently aggravating the HT-caused injury phenotype.

Characteristics of SlCML39, a Tomato Calmodulin-like Gene, and Its Negative Role in High Temperature Tolerance of Arabidopsis thaliana during Germination and Seedling Growth.

Calmodulin-like (CML) proteins are primary calcium sensors and function in plant growth and response to stress stimuli. However, so far, the function of plant CML proteins, including tomato, is still unclear. Previously, it was found that a tomato (Solanum lycopersicum) CML, here named SlCML39, was significantly induced by high temperature (HT) at transcription level, but its biological function is scarce. In this study, the characteristics of SlCML39 and its role in HT tolerance were studied. SlCML39 encodes a protein of 201 amino acids containing four EF hand motifs. Many cis-acting elements related to plant stress and hormone response appear in the promoter regions of SlCML39. SlCML39 is mainly expressed in the root, stem, and leaf and can be regulated by HT, cold, drought, and salt stresses as well as ABA and H2O2. Furthermore, heterologous overexpression of SlCML39 reduces HT tolerance in Arabidopsis thaliana at the germination and seedling growth stages. To better understand the molecular mechanism of SlCML39, the downstream gene network regulated by SlCML39 under HT was analyzed by RNA-Seq. Interestingly, we found that many genes involved in stress responses as well as ABA signal pathway are down-regulated in the transgenic seedlings under HT stress, such as KIN1, RD29B, RD26, and MAP3K18. Collectively, these data indicate that SlCML39 acts as an important negative regulator in response to HT stress, which might be mediated by the ABA signal pathway.

De Novo Design of a Robust Fluorescent Probe for Basal HClO Imaging in a Mouse Parkinson's Disease Model.

Elevated HClO gets involved in the pathogenesis of Parkinson's disease (PD). Herein, a novel fluorescent probe NUU-1 was designed and synthesized. Distinct from the general strategies, NUU-1 features two distinct HClO reactive sites, a HClO-specific reaction site and a HClO-nonspecific reactive site, which in turn endows NUU-1 with the "0 + 1 > 1" amplification effect, that thus dramatically promotes the selectivity. NUU-1 displayed a fast response rate (within 15 s), remarkable fluorescence enhancement (about 538-fold), and excellent sensitivity (LOD = 25.8 nM) in response to HClO while the remaining fluorescence silence toward other common ROS (H2O2, •OH, ONOO-, O2•-, and 1O2) even at high concentrations (up to 0.5 mM). NUU-1 allows for the imaging of both exogenous and endogenous HClO in living dopaminergic cells (SH-SY5Y). Moreover, by employing NUU-1 as the probe, the image of HClO in C. elegans and zebrafish was successfully achieved. Significantly, in the first trial, NUU-1 was successfully utilized for the brain basal HClO imaging in PD mice models and distinguished PD brain tissues from normal control, thereby holding great potential for in-depth biological applications.

Aggregation-enhanced emission enables phenothiazine coumarin as a robust ratiometric fluorescent for rapid and selective detection of HClO.

By taking advantage of phenothiazine moiety as an electron-donating group, a novel donor-acceptor (D-A) type coumarin dye, PTZ-Et, was developed. The introduction of phenothiazine moiety not only caused emission red-shifting and Stokes shift enlarging, but also endowed PTZ-Et with significant aggregation-enhanced emission (AEE) features, thereby enabled PTZ-Et as a robust ratiometric fluorescent probe for HClO detection. Upon oxidation of the sulfur atom on phenothiazine into sulfoxide, PTZ-Et displayed remarkable ratiometric fluorescence response (over 150 folds variations of F534/F626) toward HClO with rapid response time (<30 s) and ultra-sensitivity (LOD = 15 nM). Additionally, the corresponding sensing mechanism of PTZ-Et for HClO was fully elucidated through the successful purification and well characterization (1H NMR, 13C NMR, HRMS, and single crystal data) of the corresponding reaction product between PTZ-Et and HClO. Significantly, PTZ-Et was capable of monitoring both exogenous and endogenous HClO in living RAW 264.7 cells by ratiometric fluorescence imaging.

High-yield synthesis of monodisperse gold nanorods with a tunable plasmon wavelength using 3-aminophenol as the reducing agent.

Facile synthesis of high quality gold nanorods (AuNRs) with a tunable size is of great value for applications of AuNRs in various fields and for the study of the growth mechanism of such anisotropic nanostructures. However, limitations usually exist in a specific synthetic protocol. In this work, using 3-aminophenol as the reducing agent, we present a AuNR synthetic strategy with an excellent comprehensive performance, which includes an exceptional monodispersity, a AuNR shape purity of around 99%, a conversion ratio of the gold precursor of about 91%, and an easily tuned longitudinal surface plasmon resonance wavelength ranging from 580 to ∼1050 nm. Studies on the impacts of the experimental parameters including silver ions, gold seeds, reducing agent, and cetyltrimethylammonium bromide (CTAB) revealed a profound recognition of the significant effect of the reductive atmosphere, in synergy with other parameters, in directing the growth and structural evolution of the gold seeds, thus deeply affecting the size, shape yield, monodispersity, and morphology of the final structure. These results could be immensely useful for the application and revelation of the growth mechanism of AuNRs.

The Association Between Mobile Game Addiction and Depression, Social Anxiety, and Loneliness.

As a new type of addictive behaviors and distinct from traditional internet game addiction on desktop computers, mobile game addiction has attracted researchers' attention due to its possible negative effects on mental health issues. However, very few studies have particularly examined the relationship between mobile game addiction and mental health outcomes, due to a lack of specified instrument for measuring this new type of behavioral addiction. In this study, we examined the relationship between mobile game addition and social anxiety, depression, and loneliness among adolescents. We found that mobile game addiction was positively associated with social anxiety, depression, and loneliness. A further analysis on gender difference in the paths from mobile game addiction to these mental health outcomes was examined, and results revealed that male adolescents tend to report more social anxiety when they use mobile game addictively. We also discussed limitations and implications for mental health practice.

Unexpected reaction patterns enable simultaneous differentiation of H2S, H2Sn and biothiols.

A robust fluorescent probe, MCP1, was developed for triple-detection of H2S, H2Sn and biothiols for the first time. Introduction of H2S, H2Sn and biothiols to MCP1 lead to distinct emission peaks at 508, 576 and 469 nm, respectively, enabling simultaneous detection of H2S, H2Sn and biothiols from distinct emission channels.

Defluorinative C(sp3 )-P Bond Construction for the Synthesis of Phosphorylation gem-Difluoroalkenes under Catalyst- and Oxidant-Free Conditions.

Defluorinative C(sp3 )-P bond formation of α-trifluoromethyl alkenes with phosphine oxides or phosphonates have been achieved under catalyst- and oxidant-free conditions, giving phosphorylation gem-difluoroalkenes as products. α-Trifluoromethyl alkenes bearing various of aryl substituents such as halogen, cyano, ester and heterocyclic groups are available in this transformation. The results of control experiments demonstrated that the mechanism of dehydrogenative/defluorinative cross-coupling reactions was not a radical route, but might be an SN 2' process involving phosphine oxide anion.

An endoplasmic reticulum-targetable fluorescent probe for highly selective detection of hydrogen sulfide.

Hydrogen sulfide (H2S), a critical endogenous signaling molecule, is widely involved in many physiological processes. Endoplasmic reticulum, an important organelle with a sac-like structure, plays crucial roles in maintaining the normal function of cells. Accordingly, monitoring the H2S levels in endoplasmic reticulum is of great importance. Herein, we have developed an endoplasmic reticulum-targetable fluorescent probe, ER-CN, for H2S detection. ER-CN features excellent sensing properties, such as high sensitivity and selectivity. In addition, ER-CN exhibits low cytotoxicity and a fine endoplasmic reticulum targeting property (with a Pearson's colocalization coefficient of 0.95). Significantly, visualization of H2S in the endoplasmic reticulum of living HeLa cells by using ER-CN was successfully realized.

A lysosome-targetable fluorescent probe for the simultaneous sensing of Cys/Hcy and GSH from different emission channels.

A lysosome-specific fluorescent probe, Lyso-AC, for biothiols was developed by incorporation of a 4-nitrophenol moiety into a coumarin dye. The Cys/Hcy-triggered substitution-rearrangement cascade, and GSH-induced substitution reaction lead to the corresponding blue emissive amino-coumarin and yellow emissive thiol-coumarin, thereby enabling Cys/Hcy and GSH detection from distinct emissions. Moreover, this probe displayed an excellent lysosome targeting property with a 0.92 Pearson's colocalization coefficient by using Neutral Red as a reference. Significantly, biological experiments indicated Lyso-AC has the potential to monitor lysosome Cys/Hcy and GSH simultaneously in living HeLa cells from distinct emissions.

Simultaneous Discrimination of Cysteine, Homocysteine, Glutathione, and H2S in Living Cells through a Multisignal Combination Strategy.

Biothiols are essential reactive sulfur species (RSS), which play crucial roles in various critical physiological activities. To clarify their complex correlations in signal transduction and metabolism pathways, methods to distinguish H2S, cysteine (Cys), homocysteine (Hcy), and glutathione (GSH) at the same time are highly needed. Herein, we deliberately integrate 7-diethylcoumarin and resorufin through an ether bond to develop RC for simultaneous differentiation of Cys, Hcy, GSH, and H2S for the first time. RC displays distinct fluorescence colors in response to H2S, Cys, Hcy, and GSH as red, blue-red, blue-green-red, and green-red, respectively, both in aqueous media and living cells. This work not only reported a robust molecule, RC, to disentangle the intricate interplay networks among different biothiols in biosystems but also demonstrated a strategy for the design of multisignal fluorescent probes for the simultaneous sensing of diverse RSS species as well as other biological species.

A Lysosome-Targetable Fluorescent Probe for Simultaneously Sensing Cys/Hcy, GSH, and H2S from Different Signal Patterns.

Biothiols, a vital branch of reactive sulfur species (RSS) family, are indispensable in human physiology. However, the exact functional roles of each biothiol involved in complicated physiological activities are still not fully clarified. A critical barrier is a lack of robust molecular tools which can simultaneously visualize different biothiols with distinct emission signals. Herein, the first lysosome-targetable fluorescent probe, Lyso-RC, which could respond to Cys/Hcy, GSH, and H2S with different sets of signal patterns was developed. Lyso-RC responds to Cys/Hcy, GSH, and H2S with the fluorescence signal patterns of blue-red, green-red, and red, respectively. Significantly, Lyso-RC is capable of discriminating lysosomal Cys/Hcy, GSH, and H2S in HeLa cells.

Simultaneous Detection of Glutathione and Hydrogen Polysulfides from Different Emission Channels.

Glutathione (GSH) and hydrogen polysulfides (H2Sn) play crucial roles in many physiological processes. To unravel the complicated interrelationship and cellular cross-talk between GSH and H2Sn, the development of single-molecule fluorescent probes that can selectively sense GSH and H2Sn simultaneously from different emission channels is highly desirable. In this report, we have developed the first dual-detection fluorescent probe, ACC-SePh, which responded to GSH with green fluorescence emission, whereas it reacted with H2Sn and emitted blue fluorescence. The probe exhibited excellent selectivity and sensitivity toward GSH and H2Sn over other common reactive sulfur species, such as Cys, Hcy and H2S. Importantly, we also demonstrated that ACC-SePh can be used for dual-channel imaging of endogenous GSH and H2Sn in living RAW264.7 cells.

Systematical investigation of in vitro interaction of InP/ZnS quantum dots with human serum albumin by multispectroscopic approach.

Cadmium-free quantum dots (QDs) have attracted great attention in biological and biomedical applications due to their less content of toxic metals, but their potential toxicity investigations on molecular biology level are rarely involved. Since few studies have addressed whether InP/ZnS QDs could bind and alter the structure and function of human serum albumin (HSA), in vitro interaction between InP/ZnS QDs and HSA was systematically characterized by multispectroscopic approaches. InP/ZnS QDs could quench the intrinsic fluorescence of HSA via static mode. The binding site of InP/ZnS QDs was mainly located at subdomain IIA of HSA. Some thermodynamic parameters suggested that InP/ZnS QDs interacted with HSA mainly through electrostatic interactions. As further revealed by three-dimensional spectrometry, FT-IR spectrometry and circular dichroism technique, InP/ZnS QDs caused more global and local conformational change of HSA than CdSe/ZnS QDs, which illustrated the stronger binding interaction and higher potential toxicity of InP/ZnS QDs on biological function of HSA. Our results offer insights into the in vitro binding mechanism of InP/ZnS QDs with HSA and provide important information for possible toxicity risk of these cadmium-free QDs to human health.

Molecular interaction investigation between three CdTe:Zn(2+) quantum dots and human serum albumin: A comparative study.

Water-soluble Zn-doped CdTe quantum dots (CdTe:Zn(2+) QDs) have attracted great attention in biological and biomedical applications. In particular, for any potential in vivo application, the interaction of CdTe:Zn(2+) QDs with human serum albumin (HSA) is of greatest importance. As a step toward the elucidation of the fate of CdTe:Zn(2+) QDs introduced to organism, the molecular interactions between CdTe:Zn(2+) QDs with three different sizes and HSA were systematically investigated by spectroscopic techniques. Three CdTe:Zn(2+) QDs with maximum emission of 514 nm (green QDs, GQDs), 578 nm (yellow QDs, YQDs), and 640 nm (red QDs, RQDs) were tested. The binding of CdTe:Zn(2+) QDs with HSA was a result of the formation of HSA-QDs complex and electrostatic interactions played major roles in stabilizing the complex. The Stern-Volmer quenching constant, associative binding constant, and corresponding thermodynamic parameters were calculated. The site-specific probe competitive experiments revealed that the binding location of CdTe:Zn(2+) QDs with HSA was around site I. The microenvironmental and conformational changes of HSA induced by CdTe:Zn(2+) QDs were analyzed. These results suggested that the conformational change of HSA was dramatically at secondary structure level and the biological activity of HSA was weakened in the present of CdTe:Zn(2+) QDs with bigger size.

[Study on the optimal extraction process of polysaccharide from Baphicacanthus cuaia (Nees) Bremek with the uniform design].

OBJECTIVE: To study the optimal extraction process of polysaccharide from Baphicacanthus cuaia (Nees) Bremek. METHODS: The optimal extraction process was selected with uniform design and statistical analysis system (SAS). The content of polysaccharide in the extract was determined to investigate the influence of temperature of extraction, the time of extraction and the solid-liquid ratio on it. RESULTS: The optimal extraction process was extraction temperature 90 degrees C with 2 hours and with 1:50 (g/ml) of Baphicacanthus cuaia (Nees) Bremek weight to distilled water. The optimum extraction rates of Polysaccharide from Baphicacanthus cuaia (Nees) Bremek and Isatis indigotica Fort were 3.26% and 12.76%.