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Hydraulic fracturing has become one of the most important aspects of well completion because of the ever-increasing development of unconventional oil and gas reservoirs. Uncontrolled fluid flowback after the fracture treatment has the potential to impact well productivity and profitability, as aggressive flowback strategies can damage a well’s completion while conservative flowback procedures may hinder near-term economic performance.

Gamma-hydroxybutyric acid (GHB) is a commonly used “date rape” drug in drug-facilitated sexual assaults (DFSA) due to its low price and ready availability, and it is more quickly excreted from the human body than other drugs. Therefore, the development of a real-time detection method for GHB could help facilitate law enforcement agencies in tackling DFSA. In this work, a long-lived iridium(III) chemosensor 1 has been synthesized for the switch-off detection of GHB. Upon addition of GHB to an aqueous solution of the iridium(III) complex 1, a significant luminescence quenching occurred that could be observed by the naked eye under UV illumination. The luminescence signal of the iridium(III) complex 1 could also be distinguished from strongly fluorescent media using time-resolved emission spectroscopy.

Peptidylarginine deaminase 4 (PAD4) is a crucial post-translational modifying enzyme catalyzing the conversion of arginine into citrulline residues, and mediating the formation of neutrophil extracellular traps (NETs). PAD4 plays a vital role in the occurrence and development of cardiovascular diseases, autoimmune diseases, and various tumors. Therefore, PAD4 is considered as a promising drug target for disease diagnosis and treatment. More and more efforts are devoted to developing highly efficient and selective PAD4 inhibitors via high-throughput screening, structure-based drug design and structure-activity relationship study. This article outlined the physiological and pathological functions of PAD4, and corresponding representative small molecule inhibitors reported in recent years.

RNAs play important roles in various biological processes. Imaging of intracellular microRNAs (miRNAs) and messenger RNAs (mRNAs) not only helps us to better understand the formation and transcription of mRNAs, but also provides vital information for disease diagnosis and treatment. Recently, many efforts have been focused on the development of high-performance RNA imaging probes that directly monitor endogenous miRNAs and mRNAs inside living cells without special treatment. Such real-time and in situ monitoring of the intracellular RNA expression level offers dynamic distribution information of target RNA in living cells that promotes target mRNA/miRNA functional research. With the breakthrough in smart cell delivery techniques, efficient live cell RNA imaging probes greatly expand our knowledge of life processes and improve cancer detection accuracy. In this review, we summarize different classes of state-of-the-art live cell miRNA/mRNA optical imaging probes based on smart and versatile nanomaterials that have been reported in recent years. By featuring the designs and performance for the probes of interest, we compare advanced RNA imaging probes, provide guidance for better utilization of the existing imaging probes and suggest the design of future advanced live cell RNA imaging probes.

The adverse effects that thiourea can induce in biological systems demand the development of new methods for its detection. In this work, we present a iridium(III) complex-based chemosensor (1) containing a recognition unit for thiourea. The reaction of the recognition unit with thiourea affects the long-lived excited states of the complex, leading to an enhancement of luminescence. Complex 1 showed a 3.3-fold enhanced luminescence in the presence of thiorea and a good linear relationship with thiourea ranging from 10 to 200 μM, with a limit of detection (LOD) of 3.85 μM. By using time-resolved emission spectroscopy (TRES), complex 1 could detect thiourea in the presence of interfering fluorescence. Moreover, complex 1 offers the capability to image thiourea in living HeLa cells. To our knowledge, complex 1 is the first iridium(III) complex-based sensor reported for imaging thiourea in living cells.

We have developed a Ag@Au core-shell nanoparticle (NP)/iridium(III) complex-based sensing platform for the sensitive luminescence "turn-on" sensing of cyanide ions, an acutely toxic pollutant. The assay is based on the quenching effect of Ag@Au NPs on the emission of complex 1, but luminescence is restored after the addition of cyanide anions due to their ability to dissolve the Au shell. Our sensing platform exhibited a high sensitivity toward cyanide anions with a detection limit of 0.036 μM, and also showed high selectivity for cyanide over 10-fold excess amounts of other anions. The sensing platform was also successfully applied to monitor cyanide anions in drinking water and in living cells.

In this work, we report a novel iridium(III)-based luminescent switch on-off-on probe, for the in vitro and in vivo detection of sulfide ion. The mechanism of this platform is based on the effective charge transfer quenching of the iridium(III) complex 1 by Fe3+, followed by the restoration of luminescence upon the addition of Na2S. The probe, hereinafter referred to as 1–Fe3+, exhibited a linear range of detection for Na2S from 0.01 to 1.5 mM, with a detection limit of 2.9 μM at signal-to-noise ratio (S/N) of 3. We also demonstrate the utility of 1–Fe3+ for cell-based imaging as well as for the detection of enzymatic sulfide generation in living zebrafish.

A sensitive turn-on luminescent sensor for H2O2 based on the silver nanoparticle (AgNP)-mediated quenching of an luminescent Ir(III) complex (Ir-1) has been designed. In the absence of H2O2, the luminescence intensity of Ir-1 can be quenched by AgNPs via non-radiative energy transfer. However, H2O2 can oxidize AgNPs to soluble Ag+ cations, which restores the luminescence of Ir-1. The sensing platform displayed a sensitive response to H2O2 in the range of 0−17 μM, with a detection limit of 0.3 μM. Importantly, the probe was successfully applied to monitor intracellular H2O2 in living cells, and it also showed high selectivity for H2O2 over other interfering substances.

A cyclometalated iridium(III) complex has been synthesized as a novel luminescent probe for G-quadruplex (G4) DNA in aqueous solution, and a G4-based assay was employed for the detection of nicking endonuclease activity using Nb.BsmI as a model enzyme. In the assay, an initial hairpin DNA (5′- TG4AG3TG4AG3TG4A2G3A2TGCTA3TAGCAT2C3T2C4AC-3′) sequence containing the Nb.BsmI recognition site in its stem region and a partially caged G-rich DNA sequence at its 5′-terminus could be cleaved by Nb.BsmI, which liberates the G-rich DNA sequence and enhances the luminescence of complex 1. This assay showed a linear relation between luminescent signal and Nb.BsmI concentration over the range of 0–10 U/mL (R2 = 0.9937) with a detection limit for Nb.BsmI of 0.042 U/mL. Furthermore, this assay showed high selectivity for Nb.BsmI over other nicking endonucleases, and functioned effectively in the presence of cell lysates.

The relationship between childhood risk factors and long-term arterial stiffness was explored.A baseline survey was conducted in 4623 school children aged 6-15 years in rural areas of Hanzhong city, Shaanxi, in 1987. According to three independent measurements of SBP in 1987, 1989, and 1992, cases of the same age and sex with continuous SBP at least 75 percentile were classified as the high-blood pressure (BP) group, whereas those with SBP less than 50 percentile were classified as the normal-BP group. The cohort was followed up again after 26 years (in 2013). Blood biochemistry indexes, including fasting glucose, uric acid, and blood lipid, were measured. Brachial-ankle pulse wave velocity (baPWV) was recorded by noninvasive automatic waveform analyzer.Follow-up rate was 71.6%. The high-BP group had a higher incidence of hypertension (39.5 vs. 18.0%, P 0.01) and baPWV (1337.2 ± 198.3 vs. 1271.7 ± 204.3 cm/s, P = 0.028) than the normal-BP group during the follow-up period. Positive correlation was found during follow-up between baPWV and childhood SBP, as well as SBP, DBP, BMI, heart rate, total cholesterol, low-density lipoprotein cholesterol, triacylglycerol, fasting glucose, and uric acid in adulthood (all P 0.05). Results from stepwise multivariate regression analysis showed that men, family history of hypertension, SBP at both baseline and follow-up, fasting glucose, and uric acid in adulthood are independent impact factors of baPWV in adults.Higher SBP in children and adolescents, family history of hypertension, and male sex may increase the risk of developing long-term arterial stiffness.

The 3′–5′ exonuclease plays key roles in maintaining genome stability; therefore, the detection of 3′–5′ exonuclease activity is very important for disease diagnosis and drug development. In this study, we present a novel highly sensitive and label-free fluorescent assay to detect the activity of exonuclease III (Exo III) using molecular beacon DNA with a polythymine (T) loop as a template for the formation of fluorescent copper nanoparticles (CuNPs). Upon the addition of Exo III, the molecular beacon probe was digested into mono- or short oligonucleotides by the exonucleases and failed to form fluorescent CuNPs. As a result, the fluorescence intensity of CuNPs decreased. This method exhibited a very low detection limit of 0.02 U mL−1 for Exo III. The designed molecular beacon probe can be a potential label-free strategy for the detection of other nuclease activity.

A series of luminescent iridium(iii) complexes were synthesized and evaluated for their ability to interact with hydroxide ions in semi-aqueous media at ambient temperature. Upon the addition of OH-, a nucleophilic aromatic substitution reaction takes place at the bromine groups of the N^N ligand of complex 1, resulting in the generation of a yellow-green luminescence. Complex 1 showed a 35-fold enhanced emission at pH 14 when compared to neutral pH, and the detection limit for OH- ions was 4.96 μM. Complex 1 exhibited high sensitivity and selectivity, long-lived luminescence and impressive stability. Additionally, we have demonstrated the practical application of complex 1 to detect OH- ions in simulated wastewater.

A rapid and sensitive detection platform for GSH has been constructed by combining a MnO2 nanosheet with a luminescent iridium(III) complex [Ir(Cl-phq)2(Cl-phen)]+. The MnO2 nanosheet was prepared by using a facile one-step approach and was characterized by TEM. The luminescence intensity of the detection platform responded linearly with the GSH concentration from 1 to 200 μM (R2 = 0.9951), and the detection limit for GSH was 0.13 μM. More importantly, practical application of the detection platform for visualizing the intracellular GSH distribution in living zebrafish has also been demonstrated.

Background and aims Anthosachne Steudel is a group of allopolyploid species that was derived from hexaploidization between the Asian StY genome Roegneria entity and the Australasia W genome Australopyrum species. Polyploidization and apomixis contribute to taxonomic complexity in Anthosachne Here, a study is presented on the phylogeny and evolutionary history of Anthosachne australasica The aims are to demonstrate the process of polyploidization events and to explore the differentiation patterns of the St genome following geographic isolation. Methods Chloroplast rbcL and trnH-psbA and nuclear Acc1 gene sequences of 60 Anthosachne taxa and nine Roegneria species were analysed with those of 33 diploid taxa representing 20 basic genomes in Triticeae. The phylogenetic relationships were reconstructed. A time-calibrated phylogeny was generated to estimate the evolutionary history of A. australasica Nucleotide diversity patterns were used to assess the divergence within A. australasica and between Anthosachne and its putative progenitors. Key results Three homoeologous copies of the Acc1 sequences from Anthosachne were grouped with the Acc1 sequences from Roegneria, Pseudoroegneria, Australopyrum, Dasypyrum and Peridictyon The chloroplast sequences of Anthosachne were clustered with those from Roegneria and Pseudoroegneria Divergence time for Anthosachne was dated to 4·66 million years ago (MYA). The level of nucleotide diversity in Australasian Anthosachne was higher than that in continental Roegneria A low level of genetic differentiation within the A. australasica complex was found. Conclusions Anthosachne originated from historical hybridization between Australopyrum species and a Roegneria entity colonized from Asia to Australasia via South-east Asia during the late Miocene. The St lineage served as the maternal donor during the speciation of Anthosachne A contrasting pattern of population genetic structure exists in the A. australasica complex. Greater diversity in island Anthosachne compared with continental Roegneria might be associated with mutation, polyploidization, apomixis and expansion. It is reasonable to consider that A. australasica var. scabra and A. australasica var. plurinervisa should be included in the A. australasica complex.

A label-free fluorescence assay has been developed for sensitive and selective detection of adenosine triphosphate (ATP) by using poly(thymine) (poly T)-templated copper nanoparticles (CuNPs) as fluorescent indicator. In our design, ATP aptamer was split into two fragments, both of which were elongated with poly T strands that can be utilized as efficient template for the formation of copper nanoparticles through the reduction of copper ions by sodium ascorbate. In the presence of ATP, the two split aptamers could be dragged to form aptamer-ATP aptamer complex, which drew the poly T strands close to each other and induced a remarkable fluorescence enhancement of poly T-templated CuNPs. Thus, an elevated fluorescence enhancement of poly T-templated CuNPs was obtained with the increase in ATP concentration. Under optimized conditions, a good linear range for ATP detection was realized from 100 nM to 100 μM with a detection limit of 10.29 nM. In addition, the application of this biosensing system in complex biological matrix was demonstrated with satisfactory results. This assay provided a simple, label-free, cost-effective, and sensitive platform for the detection of ATP.

Dephosphorylation of DNA by DNA 3′-phosphatases plays significant regulatory roles in DNA damage repair, replication, and recombination. Here, we present a novel, highly sensitive and label-free fluorescent assay for T4 polynucleotide kinase/phosphatase (T4 PNKP) activity and its inhibitors on the basis of nicking enzyme-assisted signal amplification and poly(thymine)-templated fluorescent copper nanoparticles (CuNPs) as a fluorescent indicator. It was designed such that an A-rich hairpin primer with a 3′-phosphoryl end can serve as the substrate for T4 PNKP. Once the phosphorylated hairpin primer was hydrolyzed by T4 PNKP, the resulting hairpin primer with a 3′-hydroxyl end was immediately elongated to form a long double-strand product using DNA polymerase as well as a double-stranded recognition site for nicking enzyme Nb.BbvCI. With the help of nicking enzyme Nb.BbvCI, the double-strand product could be cleaved to release a single-stranded poly-(thymine) (poly T) DNA, which could be used as a template for the formation of fluorescent CuNPs. Subsequently, the remaining probe could be reacted as the primer to trigger the next cycle of polymerization and scission process, thus significantly improving the sensitivity of the sensor. Furthermore, the application of the proposed strategy for screening T4 PNKP inhibitors also demonstrated satisfactory results. With the advantages mentioned above, this simple, cost-effective, and highly sensitive strategy has potential for the study of DNA damage repair mechanisms.

DNA 3'-phosphatase takes an important role in DNA damage repair, replication and recombination. Here, we present a novel label-free fluorescent assay for T4 polynucleotide kinase/phosphatase (T4 PNKP) activity and its inhibitor screening by using poly(thymine)-templated fluorescent copper nanoparticles (CuNPs) as a fluorescent indicator. In this assay, we designed a simple T-rich hairpin primer with a 3'-phosphoryl end, which can serve as both the substrate for T4 PNKP and DNA template for the formation of fluorescent CuNPs. Once the phosphorylated hairpin primer was hydrolyzed by T4 PNKP, the resulting hairpin primer with a 3'-hydroxyl end was immediately elongated to form a long double-strand product by DNA polymerase, which prohibited the formation of fluorescent CuNPs due to the lack of poly T single-stranded DNA template. This new strategy provides a sensitive, selective, and cost-effective manner for T4 PNKP analysis, which holds a great potential in the study of DNA damage repair mechanisms.

We have developed a novel label-free fluorescence approach for nicotinamide adenine dinucleotide (NAD+) detection by coupling poly(AT-TA) dsDNA-templated fluorescent copper nanoparticles (CuNPs) as a fluorescence indicator with a dumbbell DNA probe designed for ligation. Herein, we designed a dumbbell probe which can form a self-complementary structure at both ends. In the absence of NAD+, the extension reaction can be performed from the exposed 3′-end, and instantly opened the hybridized structure at the 5′-end, producing a chimeric poly(AT-TA) double-stranded fragment which can be used as a highly-efficient template for the formation of CuNPs, showing high fluorescence. Whereas in the presence of NAD+, together with the E. coli DNA ligase, the 5′-phosphoryl end and the 3′-end of the DNA probe can be ligated to block the extension reaction, showing slight fluorescence. This novel NAD+ assay is label-free, fast and easy to operate, highly sensitive and selective, which holds wide applicability as a robust analytical tool in NAD+ related biological processes and clinical diagnosis.

A paper-based microfluidic device based on unconventional principle was developed and used to detect lead ions through a two-step process including heated incubation and subsequent mixing. The device was made by generating a superhydrophobic pattern, which defines channel and reservoir barriers, on a water-impermeable paper substrate, followed by loading and drying the reagents in the defined reservoirs. Different from the conventional paper-based devices that are made of water-permeable paper, the as-prepared device holds water drops in discrete reservoirs, and the water drops will not move unless the device is titled along the direction of the predefined channels. In this way, the liquid samples applied onto the device are handled as individual drops and could be stored, transported, and mixed on demand. Different from the conventional paper-based devices that use capillary force to drive liquid, our new device uses wetting and gravity as driving force. We name this operation principle suspending-droplet mode paper-based device (SD-μPAD). The use of a Teflon contact-printing stamp makes the production of such devices rapid, cost efficient, and mass productive. Utilizing a G-quadruplex-based luminescence switch-on assay, we demonstrated rapid, convenient, highly sensitive, and low cost detection of lead(II) ions in water samples, using a custom made battery-powered portable device, and a smart phone as the detector.

A series of luminescent iridium(iii) complexes were synthesized and evaluated for their ability to interact with hydroxide ions in semi-aqueous media at ambient temperature. Upon the addition of OH

The hypoxia inducible factor (HIF) pathway has been considered to be an attractive anti-cancer target. One strategy to inhibit HIF activity is through the disruption of the HIF-1α–p300 protein-protein interaction. We report herein the identification of an osmium(II) complex as the first metal-based inhibitor of the HIF-1α–p300 interaction. We evaluated the effect of complex 1 on HIF-1α signaling pathway in vitro and in cellulo by using the dual luciferase reporter assay, co-immunoprecipitation assay, and immunoblot assay. Complex 1 exhibited a dose-dependent inhibition of HRE-driven luciferase activity, with an IC50 value of 1.22 μM. Complex 1 interfered with the HIF-1α–p300 interaction as revealed by a dose-dependent reduction of p300 co-precipitated with HIF-1α as the concentration of complex 1 was increased. Complex 1 repressed the phosphorylation of SRC, AKT and STAT3, and had no discernible effect on the activity of NF-κB. We anticipate that complex 1 could be utilized as a promising scaffold for the further development of more potent HIF-1α inhibitors for anti-cancer treatment.

By catalyzing highly specific and tightly controlled chemical reactions, enzymes are essential to maintaining normal cellular physiology. However, aberrant enzymatic activity can be linked to the pathogenesis of various diseases. Therefore, the unusual activity of particular enzymes can represent testable biomarkers for the diagnosis or screening of certain diseases. In recent years, G-quadruplex-based platforms have attracted wide attention for the monitoring of enzymatic activities. In this Personal Account, we discuss our group's works on the development of G-quadruplex-based sensing system for enzyme activities by using mainly iridium(III) complexes as luminescent label-free probes. These studies showcase the versatility of the G-quadruplex for developing assays for a variety of different enzymes.

A rapid and sensitive detection platform for GSH has been constructed by combining a MnO

In this paper, combining with the domestic design and application of the snowplow in quality and quantity two aspects, basing on engineering application software ADAMS and CATIA, dynamics for 10t snowplow working device was researched, and the strength of the main stress components was analyzed by finite element method. On the basis of lightweight, strength and structure reasonable design, the snowplow device structure was verified feasibility through the research results. The paper studies could have a certain theoretical reference for the theoretical design and practical application of similar products.

To estimate the origin and genomic relationships of the polyploid species within Elymus L. sensu lato, two unlinked single-copy nuclear gene (Acc1 and Pgk1) sequences of eighteen tetraploids (StH and StY genomes) and fourteen hexaploids (StStH, StYP, StYH, and StYW genomes) were analyzed with those of 35 diploid taxa representing 18 basic genomes in Triticeae. Sequence and phylogenetic analysis suggested that: (1) the St, H, W, and P genomes were donated by Pseudoroegneria, Hordeum, Australopyrum, and Agropyron, respectively, while the Y genome is closely related to the Xp genome in Peridictyon sanctum; (2) different hexaploid Elymus s.l. species may derived their StY genome from different StY genome tetraploid species via independent origins; (3) due to incomplete lineage sorting and/or hybridization events, the genealogical conflict between the two gene trees suggest introgression involving some Elymus s.l. species, Pseudoroegneria, Agropyron and Aegilops/Triticum; (4) it is reasonable to recognize the StH genome species as Elymus sensu stricto, the StY genome species as Roegneria, the StYW genome species as Anthosachne, the StYH genome species as Campeiostachys, and the StYP genome species as Kengyilia. The occurrence of multiple origin and introgression could account for the rich diversity and ecological adaptation of Elymus s.l. species.

Analysis of the patterns and levels of diversity in duplicate gene not only traces evolutionary history of polyploids, but also provides insight into how the evolutionary process differs between lineages and between homoeologous loci within lineages. Elymus sensu lato is a group of allopolyploid species, which share a common St genome and with the different combinations of H, Y, P, and W genomes. To estimate the evolutionary process of the rbc L gene in species of Elymus s. l. and its putative dioploid relatives, 74 sequences were obtained from 21 species of Elymus s. l. together with 24 diploid taxa representing 19 basic genomes in Triticeae. Phylogeny and sequence diversity pattern analysis suggested that (1) species of Pseudoroegneria (Nevski) A. Love might serve as the maternal donor of the species of Elymus s. l; (2) differentiation of St genome were shown in the species of Elymus s. l. following polyploidy event; (3) divergences within the species might associate with geographic diversity and morphological variability; (4) differences in the levels and patterns of nucleotide diversity of the rbc L gene implied that the St genome lineages in the species of Elymus s. l. have differently evolutionary potentials.

Four benzofuran-conjugated iridium(III) or rhodium (III)-based metal complexes are synthesized to screen as an inhibitor of STAT3 activity in prostate cancer cells. All complexes show the high stability and solubility in the biological system. In this study, an iridium(III) complex engages STAT3 and NF-κB to inhibit their translocation and transcriptional activities. Moreover, complex 1 shows more potential antiproliferative activity against DU145 cells and suppresses tumor growth in a prostate cancer xenograft mouse without observable adverse effects. Complex 1 may provide the basis for developing new therapeutic strategy in vivo and in vitro for the treatment of advanced prostate cancer.

A long-lived aldol reaction-based iridium(III) chemosensor [Ir(ppy)2(5-CHOphen)]PF6 (1, where ppy = 2-phenylpyridine and 5-CHOphen = 1,10-phenanthroline-5-carbaldehyde) for proline detection has been synthesized. The iridium(III) complex 1, incorporating an aldehyde group in N^N donor ligand, can take part in aldol reaction with acetone mediated by proline. The transformation of the sp2-hybridized carbonyl group into a sp3-hybridized alcohol group influences the metal-to-ligand charge-transfer (MLCT) state of the iridium(III) complex, resulting in a change in luminescence in response to proline. The interaction of the iridium(III) complex 1 with proline was investigated by 1H NMR, HRMS and emission titration experiments. Upon the addition of proline to a solution of iridium(III) complex 1, a maximum 8-fold luminescence enhancement was observed. The luminescence signal of iridium(III) complex 1 could be recognized in strongly fluorescent media using time-resolved emission spectroscopy (TRES). The detection of proline in living cells was also demonstrated.

Background Hybridization and polyploidization can be major mechanisms for plant evolution and speciation. Thus, the process of polyploidization and evolutionary history of polyploids is of widespread interest. The species in Elymus L. sensu lato are allopolyploids that share a common St genome from Pseudoroegneria in different combinations with H, Y, P, and W genomes. But how the St genome evolved in the Elymus s. l. during the hybridization and polyploidization events remains unclear. We used nuclear and chloroplast DNA-based phylogenetic analyses to shed some light on this process. Results The Maximum likelihood (ML) tree based on nuclear ribosomal internal transcribed spacer region (nrITS) data showed that the Pseudoroegneria, Hordeum and Agropyron species served as the St, H and P genome diploid ancestors, respectively, for the Elymus s. l. polyploids. The ML tree for the chloroplast genes (matK and the intergenic region of trnH-psbA) suggests that the Pseudoroegneria served as the maternal donor of the St genome for Elymus s. l. Furthermore, it suggested that Pseudoroegneria species from Central Asia and Europe were more ancient than those from North America. The molecular evolution in the St genome appeared to be non-random following the polyploidy event with a departure from the equilibrium neutral model due to a genetic bottleneck caused by recent polyploidization. Conclusion Our results suggest the ancient common maternal ancestral genome in Elymus s. l. is the St genome from Pseudoroegneria. The evolutionary differentiation of the St genome in Elymus s. l. after rise of this group may have multiple causes, including hybridization and polyploidization. They also suggest that E. tangutorum should be treated as C. dahurica var. tangutorum, and E. breviaristatus should be transferred into Campeiostachys. We hypothesized that the Elymus s. l. species origined in Central Asia and Europe, then spread to North America. Further study of intraspecific variation may help us evaluate our phylogenetic results in greater detail and with more certainty. Electronic supplementary material The online version of this article (doi:10.1186/s12870-015-0517-2) contains supplementary material, which is available to authorized users.

A novel label-free nanosensor has been developed for detecting biothiols including cysteine, glutathione and homocysteine based on poly(thymine)-templated fluorescent copper nanoparticles (CuNPs), which were controlled through thymine-Hg(II)-thymine coordination. This assay provides a simple, cost-effective, and sensitive platform for the detection of biothiols. By employing this turn-on sensor, biological thiols, such as cysteine, glutathione and homocysteine, are successfully detected at concentrations as low as 12.5nM for cysteine, 15nM for glutathione, and 20nM for homocysteine. The sensing system also exhibits high selectivity against other amino acids, and the application of the sensor for biological fluids shows that the proposed method works well for real samples.

Objective: The aim of our study was to assess the effects of altered salt and potassium intake on urinary renalase and serum dopamine levels in humans. Methods: Forty-two subjects (28-65 years of age) were selected from a rural community of northern China. All subjects were sequentially maintained on a low-salt diet for 7 days (3.0 g/day of NaCl), a high-salt diet for an additional 7 days (18.0 g/day of NaCl), and a high-salt diet with potassium supplementation for a final 7 days (18.0 g/day of NaCl + 4.5 g/day of KCl). Results: Urinary renalase excretions were significantly higher during the high-salt diet intervention than during the low-salt diet. During high-potassium intake, urinary renalase excretions were not significantly different from the high-salt diet, whereas they were significantly higher than the low-salt levels. Serum dopamine levels exhibited similar trends across the interventions. Additionally, a significant positive relationship was observed between the urine renalase and serum dopamine among the different dietary interventions. Also, 24-hour urinary sodium excretion positively correlated with urine renalase and serum dopamine in the whole population. Conclusions: The present study indicates that dietary salt intake and potassium supplementation increase urinary renalase and serum dopamine levels in Chinese subjects.