Physisorption Behaviors of Organochlorine Pesticides on the InP3 Monolayer from Theoretical Insight.

Dichlorodiphenyltrichloroethane (DDT), hexachlorocyclohexane (BHC), aldrin, and chlordimeform are ubiquitous organochlorine pesticide (OCP) residues in the environment, which pose a great threat to human health and ecosystems due to their high toxicity and easy accumulation. Based on the density functional theory (DFT) calculations, a two-dimensional InP3 monolayer was selected as a sensing material to study the sensitivity detection and adsorption behaviors toward BHC, aldrin, chlordimeform, and DDT. The calculation results show that four pesticide molecules are adsorbed on the InP3 surface by physical interaction. The identified response values (69.1, -43.1%) for DDT and chlordimeform reveal the potential of the InP3 monolayer as a sensing material for the detection of these two pesticides, accompanied by the achievement of cyclic utilization by heating to 498 K. The most satisfactory result is the adsorption of BHC, owing to the admirable sensing response (62.7%) and short recovery time (1.8 s) at room temperature, which makes InP3 a promising pesticide sensor for BHC. However, the InP3 surface is unsuitable for aldrin sensing due to poor response (-1.9%). Our work gives theoretical insight into the good sensitivity and recycling of the InP3 monolayer as a new pesticide sensor to detect DDT, BHC, and chlordimeform, which further broadens the application prospect of the InP3 nanosheet into the sensitive detection of organochlorine pesticides in the ecological environment.

A mitochondria-targeted dual-response sensor for monitoring viscosity and peroxynitrite in living cells with distinct fluorescence signals.

Viscosity and peroxynitrite (ONOO-) are two significant indicators to affect and evaluate the mitochondrial functional status, which are nearly relational with pathophysiological process in many diseases. Developing suitable analytical methods for monitoring mitochondrial viscosity changes and ONOO- is thus of great importance. In this research, a new mitochondria-targeted sensor DCVP-NO2 for the dual determination of viscosity and ONOO- was exploited based on the coumarin skeleton. DCVP-NO2 displayed a red fluorescence "turn-on" response toward viscosity along with about 30-fold intensity increase. Meanwhile, it could be used as ratiometric probe for detection of ONOO- with excellent sensitivity and extraordinary selectivity for ONOO- over other chemical and biological species. Moreover, thanks to its good photostability, low cytotoxicity and ideal mitochondrion-targeting capability, DCVP-NO2 was successfully utilized for fluorescence imaging of viscosity variations and ONOO- in mitochondria of living cells through different channels. In addition, the results of cell imaging revealed that ONOO- would lead to the increase of viscosity. Taken together, this work provides a potential molecular tool for researching biological functions and interactions of viscosity and ONOO- in mitochondria.

Bimetal zeolite imidazolate framework derived Mo0.84Ni0.16-Mo2C@NC nanosphere for overall water splitting in alkaline solution.

The bifunctional efficient electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are in urgent need for the advanced overall water splitting (OWS) device. Restricted by the thermodynamic limitations of the catalytic active center for OER and the reaction kinetics limitations induced by the structure of the electrocatalysts, the development of OWS catalysts requires more effort. Herein, a porous carbon-based bimetal electrocatalyst of Mo0.84Ni0.16-Mo2C@NC nanosphere is prepared by hydrothermal treatment of PMo12@PVP@Zn/Ni-ZIF which is synthesized via one-pot self-assembled hydrothermal method. Our study confirms that the Mo-Ni alloy and Mo2C nanoparticles homogeneously distribute in nitrogen-rich carbon-based materials. Furthermore, the porous structure exposes rich active sites and increases the effective specific area for redox reactions. The obtained Mo0.84Ni0.16-Mo2C@NC catalyst requires low overpotentials of 151 and 285 mV to reach a current density of 10 mA cm-2 towards the water reduction and oxidation in 1 M KOH solution, respectively, and possesses good catalytic stability for one day. This work introduces an advanced method for the synthesis of the bimetal electrocatalyst.

Electrochemically Exfoliated Platinum Dichalcogenide Atomic Layers for High-Performance Air-Stable Infrared Photodetectors.

Platinum dichalcogenide (PtX2), an emergent group-10 transition metal dichalcogenide (TMD) has shown great potential in infrared photonic and optoelectronic applications due to its layer-dependent electronic structure with potentially suitable bandgap. However, a scalable synthesis of PtSe2 and PtTe2 atomic layers with controlled thickness still represents a major challenge in this field because of the strong interlayer interactions. Herein, we develop a facile cathodic exfoliation approach for the synthesis of solution-processable high-quality PtSe2 and PtTe2 atomic layers for high-performance infrared (IR) photodetection. As-exfoliated PtSe2 and PtTe2 bilayer exhibit an excellent photoresponsivity of 72 and 1620 mA W-1 at zero gate voltage under a 1540 nm laser illumination, respectively, approximately several orders of magnitude higher than that of the majority of IR photodetectors based on graphene, TMDs, and black phosphorus. In addition, our PtSe2 and PtTe2 bilayer device also shows a decent specific detectivity of beyond 109 Jones with remarkable air-stability (>several months), outperforming the mechanically exfoliated counterparts under the laser illumination with a similar wavelength. Moreover, a high yield of PtSe2 and PtTe2 atomic layers dispersed in solution also allows for a facile fabrication of air-stable wafer-scale IR photodetector. This work demonstrates a new route for the synthesis of solution-processable layered materials with the narrow bandgap for the infrared optoelectronic applications.

Synthesis of nanoporous graphenes via decarboxylation reaction.

Two kinds of C-C bonded crystalline nanoporous graphenes (NPGs) have been synthesized by using a newly developed decarboxylation reaction. Both NPGs show good electrocatalytic oxygen evolution reaction (OER) activities. The clear pore-edge structures of the synthesized NPGs provide an ideal platform for further OER investigations.

Two-dimensional TiO2 nanoflakes enable rapid SALDI-TOF-MS detection of toxic small molecules (dyes and their metabolites) in complex environments.

High surface area (136 m2 g-1) nanoporous two-dimensional TiO2 nanoflakes are applied as an adsorbent and meanwhile a matrix for toxic small molecule analysis using positive-ion surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF MS). The TiO2 nanoflakes enable one-step enrichment and analysis, greatly simplifying the analysis technique. Due to the high enrichment efficiency and low background noise, small molecule organic contaminants at ppt or even sub-ppt concentrations such as malachite green (10 pg/mL), leucomalachite green (10 pg/mL), cetyltrimethylammonium bromide (0.001 pg/mL), rhodamine B (0.001 pg/mL), and crystal violet (0.1 pg/mL) were detected. In addition, malachite green and its metabolite leucomalachite green at ng/mL concentrations were successfully detected from fish blood and fish extracts, and crystal violet and its homologues at ng/cm2 concentrations were detected from inks on thermal receipt papers obtained from local supermarket.

One-Dimensional Porous Hybrid Structure of Mo2C-CoP Encapsulated in N-Doped Carbon Derived from MOF: An Efficient Electrocatalyst for Hydrogen Evolution Reaction over the Entire pH Range.

The development of outstanding noble-metal-free electrocatalysts for the hydrogen evolution reaction (HER) has attracted broad interest. Herein, a novel one-dimensional (1D) HER hybrid catalyst consisted of cobalt phosphide (CoP) and molybdenum carbide (Mo2C) nanoparticles wrapped by nitrogen-doped graphitic carbon (called CoP/Mo2C-NC) was successfully fabricated by a facile continuous-flow method and a simple two-step annealing process. During these processes, the successful synthesis of the MoO3 nanorods coated with cobalt zeolitic imidazolate frameworks (Co-ZIF-67) (Co-ZIF-67@MoO3) through the continuous-flow method plays a key role. The as-synthesized CoP/Mo2C-NC hybrid electrocatalyst exhibits a significantly enhanced HER electrocatalytic activity over the entire pH range relative to that of the control materials CoP, Mo2C-NC, and physically mixed CoP and Mo2C-NC. The outstanding HER catalytic performance is mainly due to the fact that the electron cloud transfers from Co to Mo in CoP/Mo2C-NC through the Co-P-Mo bond, resulting in the formation of a high valence state for Co (Co3+) species and lower valence states for Mo (i.e., Mo2+, Mo3+) species, providing the abundant HER active sites. Moreover, the Gibbs free energy (Δ GH*) of CoP/Mo2C-NC obtained by the density function theory calculations indicates a good balance between the Volmer and Heyrovsky/Tafel steps in HER kinetics. Such a cobalt zeolitic imidazolate framework-mediated strategy depicted in this work offers an interesting perspective for developing highly efficient noble-metal-free electrocatalysts for hydrogen production.

Porous Co9S8/Nitrogen, Sulfur-Doped Carbon@Mo2C Dual Catalyst for Efficient Water Splitting.

The exploration of highly efficient and stable bifunctional electrocatalysts for overall water splitting is currently of extreme interest for the efficient conversion of sustainable energy sources. Herein, we provide an earth-abundant, low-cost, and highly efficient bifunctional electrocatalyst composed of cobalt sulfide (Co9S8) and molybdenum carbide (Mo2C) nanoparticles anchored to metal-organic frameworks (MOFs)-derived nitrogen, sulfur-codoped graphitic carbon (Co9S8-NSC@Mo2C). The new composite mode of the electrocatalyst was realized through simple pyrolysis processes. The composite electrocatalyst shows outstanding hydrogen evolution reaction (HER) performance and excellent stability over the entire pH range. For example, it has a lower overpotential of 74, 89, and 121 mV with the Tafel slopes of 69.3, 86.7, and 106.4 mV dec-1 to achieve a current density of 10 mA cm-2 in 0.5 M H2SO4, 1.0 M KOH, and 1.0 M phosphate-buffered saline solutions, respectively. Moreover, it shows a small overpotential of 293 mV with a Tafel slope of 59.7 mV dec-1 to reach 10 mA cm-2 for the oxygen evolution reaction (OER) in 1.0 M KOH. The significantly enhanced HER and OER activities of Co9S8-NSC@Mo2C are mainly attributable to the electron transfer from Co to Mo2C, resulting in a lower Mo valence and a higher Co valence in Co9S8-NSC@Mo2C. Furthermore, using the Co9S8-NSC@Mo2C bifunctional electrocatalyst as both the anode for the OER and the cathode for the HER for overall water splitting, a cell voltage of only 1.61 V is needed to derive a current density of 10 mA cm-2. This interesting work offers a general method for designing and fabricating highly efficient and stable non-noble electrocatalysts for promising energy conversion.

Cationic Reduced Graphene Oxide as Self-Aligned Nanofiller in the Epoxy Nanocomposite Coating with Excellent Anticorrosive Performance and Its High Antibacterial Activity.

The design and preparation of an excellent corrosion protection coating is still a grand challenge and is essential for large-scale practical application. Herein, a novel cationic reduced graphene oxide (denoted as RGO-ID+)-based epoxy coating was fabricated for corrosion protection. RGO-ID+ was synthesized by in situ synthesis and salification reaction, which is stable dispersion in water and epoxy latex, and the self-aligned RGO-ID+-reinforced cathodic electrophoretic epoxy nanocomposite coating (denoted as RGO-ID+ coating) at the surface of metal was prepared by electrodeposition. The self-alignment of RGO-ID+ in the coatings is mainly attributed to the electric field force. The significantly enhanced anticorrosion performance of RGO-ID+ coating is proved by a series of electrochemical measurements in different concentrated NaCl solutions and salt spray tests. This superior anticorrosion property benefits from the self-aligned RGO-ID+ nanosheets and the quaternary-N groups present in the RGO-ID+ nanocomposite coating. Interestingly, the RGO-ID+ also exhibits a high antibacterial activity toward Escherichia coli with 83.4 ± 1.3% antibacterial efficiency, which is attributed to the synergetic effects of RGO-ID+ and the electrostatic attraction and hydrogen bonding between RGO-ID+ and E. coli. This work offers new opportunities for the successful development of effective corrosion protection and self-antibacterial coatings.

Influence Factors on Contrast Agent Venous Intravasation During Transvaginal 4-Dimensional Hysterosalpingo-Contrast Sonography.

OBJECTIVES: To explore the risk factors on contrast agent venous intravasation during transvaginal 4-dimensional hysterosalpingo-contrast sonography (TVS 4D-HyCoSy). METHODS: The TVS 4D-HyCoSy imaging data were collected from 276 female infertile patients. The correlation between endometrial thickness, days after menstruation, intrauterine intervention history, fallopian tubal patency degree, and contrast agent venous intravasation, respectively, was analyzed. RESULTS: In our study, the incidence of contrast agent venous intravasation was 13.04%. Endometrial thickness and days after menstruation were significantly associated with venous intravasation (P < .05). However, there was no significance for intrauterine intervention history and fallopian tube patency degree. CONCLUSIONS: Contrast agent intravasation during TVS 4D-HyCoSy is not infrequent. Performing TVS 4D-HyCoSy according to endometrial thickness and menstrual period could reduce intravasation incidence to some extent.

Assessment of Fallopian Tube Fimbria Patency With 4-Dimensional Hysterosalpingo-Contrast Sonography in Infertile Women.

OBJECTIVES: The purpose of this study was to evaluate the performance of 4-dimensional (4D) hysterosalpingo-contrast sonography (HyCoSy) for assessing fallopian tube fimbria patency in infertile women. METHODS: Seventy-seven infertile female patients with obstruction at the tubal fimbria or partial obstruction with pelvic adhesions were included. All of the patients underwent 4D HyCoSy enhanced by dynamic observation after a flush of normal saline and were followed with laparoscopic chromopertubation using methylene blue within 6 months. RESULTS: The overall accordance between 4D HyCoSy and laparoscopic chromopertubation was 92.9%. The sensitivity and specificity of 4D HyCoSy with laparoscopic chromopertubation as a reference standard were 93.8% and 92.2%, respectively. CONCLUSIONS: Four-dimensional HyCoSy can be the preferred method for assessment of tubal fimbria patency and pelvic adhesions surrounding the ovaries, with its advantages of accuracy, noninvasiveness, and a good safety profile.

Application of molecular imaging technologies in antitumor drug development and therapy.

Molecular imaging enables noninvasive characterization, quantification and visualization of biological and pathological processes in vivo at cellular and molecular level. It plays an important role in drug discovery and development. The skillful use of molecular imaging can provide unique insights into disease processes, which greatly aid in identifications of target. Importantly, molecular imaging is widely applied in the pharmacodynamics study to provide earlier endpoints during the preclinical drug development process, since it can be applied to monitor the effects of treatment in vivo with the use of biomarkers. Herein, we reviewed the application of molecular imaging technologies in antitumor drug development process ranging from identification of targets to evaluation of therapeutic effect.

Ultrasound-mediated local drug and gene delivery using nanocarriers.

With the development of nanotechnology, nanocarriers have been increasingly used for curative drug/gene delivery. Various nanocarriers are being introduced and assessed, such as polymer nanoparticles, liposomes, and micelles. As a novel theranostic system, nanocarriers hold great promise for ultrasound molecular imaging, targeted drug/gene delivery, and therapy. Nanocarriers, with the properties of smaller particle size, and long circulation time, would be advantageous in diagnostic and therapeutic applications. Nanocarriers can pass through blood capillary walls and cell membrane walls to deliver drugs. The mechanisms of interaction between ultrasound and nanocarriers are not clearly understood, which may be related to cavitation, mechanical effects, thermal effects, and so forth. These effects may induce transient membrane permeabilization (sonoporation) on a single cell level, cell death, and disruption of tissue structure, ensuring noninvasive, targeted, and efficient drug/gene delivery and therapy. The system has been used in various tissues and organs (in vitro or in vivo), including tumor tissues, kidney, cardiac, skeletal muscle, and vascular smooth muscle. In this review, we explore the research progress and application of ultrasound-mediated local drug/gene delivery with nanocarriers.

New progress in angiogenesis therapy of cardiovascular disease by ultrasound targeted microbubble destruction.

Angiogenesis plays a vital part in the pathogenesis and treatment of cardiovascular disease and has become one of the hotspots that are being discussed in the past decades. At present, the promising angiogenesis therapies are gene therapy and stem cell therapy. Besides, a series of studies have shown that the ultrasound targeted microbubble destruction (UTMD) was a novel gene delivery system, due to its advantages of noninvasiveness, low immunogenicity and toxicity, repeatability and temporal and spatial target specificity; UTMD has also been used for angiogenesis therapy of cardiovascular disease. In this review, we mainly discuss the combination of UTMD and gene therapy or stem cell therapy which is applied in angiogenesis therapy in recent researches, and outline the future challenges and good prospects of these approaches.

New researches and application progress of commonly used optical molecular imaging technology.

Optical molecular imaging, a new medical imaging technique, is developed based on genomics, proteomics and modern optical imaging technique, characterized by non-invasiveness, non-radiativity, high cost-effectiveness, high resolution, high sensitivity and simple operation in comparison with conventional imaging modalities. Currently, it has become one of the most widely used molecular imaging techniques and has been applied in gene expression regulation and activity detection, biological development and cytological detection, drug research and development, pathogenesis research, pharmaceutical effect evaluation and therapeutic effect evaluation, and so forth, This paper will review the latest researches and application progresses of commonly used optical molecular imaging techniques such as bioluminescence imaging and fluorescence molecular imaging.

Advance of molecular imaging technology and targeted imaging agent in imaging and therapy.

Molecular imaging is an emerging field that integrates advanced imaging technology with cellular and molecular biology. It can realize noninvasive and real time visualization, measurement of physiological or pathological process in the living organism at the cellular and molecular level, providing an effective method of information acquiring for diagnosis, therapy, and drug development and evaluating treatment of efficacy. Molecular imaging requires high resolution and high sensitive instruments and specific imaging agents that link the imaging signal with molecular event. Recently, the application of new emerging chemical technology and nanotechnology has stimulated the development of imaging agents. Nanoparticles modified with small molecule, peptide, antibody, and aptamer have been extensively applied for preclinical studies. Therapeutic drug or gene is incorporated into nanoparticles to construct multifunctional imaging agents which allow for theranostic applications. In this review, we will discuss the characteristics of molecular imaging, the novel imaging agent including targeted imaging agent and multifunctional imaging agent, as well as cite some examples of their application in molecular imaging and therapy.

[Protective effects of resveratrol on neonatal rat cardiomyocyte lesion induced by hypoxia].

OBJECTIVE: To investigate the effects of resveratrol (Res) on neonatal rat cardiomyocyte lesion induced by hypoxia. METHOD: The cardiomyocyte of neonatal rats were cultured in vitro and the model of cardiomyocyte hypoxia was established. The cardiomyocyte vitalities were determined by MTT assay, the HIF-1alpha expression levels in myocardial cells was detected by immunohistochemical, the activities of peroxidase (GSH-Px) and lactate dehydrogenase (LDH) were measured as well. RESULT: After the administration of hypoxia for 24 hours, the HIF-1alpha expression in myocardial cells was significantly increased. The LDH level in the culture medium was increased from (93.07 +/- 15.84) U x L(-1) to (750.77 +/- 181.51) U x L(-1) (P < 0.01). The intracellular GSH-Px activity was decreased from (46.96 +/- 8.36) U x mL(-1) to (27.13 +/- 4.76) U x mL(-1) (P < 0.05). Res 25, 50 and 75 micromol x L(-1) could dose-dependently inhibit the raising of the HIF-1alpha expression in myocardial cells induced by hypoxia. The LDH activities were decreased dose-dependently to (486.17 +/- 69.97), (189.43 +/- 32.07), (155.34 +/- 29.57) U x L(-1), respectively (P <0.05 or P <0.01). The GSH-Px activities were increased dose-dependently (33.55 +/- 6.34), (37.67 +/- 6.73), (41.44 +/- 7.91) U x mL(-1) (P < 0.05 or P < 0.01). CONCLUSION: Res has a protective effect on neonatal rat cardiomyocyte lesion induced by hypoxia.