Room-temperature phosphorescence and fluorescence nanocomposites as a ratiometric chemosensor for high-contrast and selective detection of 2,4,6-trinitrotoluene.

Reports on using complementary colours for high-contrast ratiometric assays are limited to date. In this work, graphitized carbon nitride (g-C3N4) nanosheets and mercaptoethylamine (MEA) capped Mn-doped ZnS QDs were fabricated by liquid exfoliation of bulk g-C3N4, and by a coprecipitation and postmodification strategies, respectively. Mn-doped ZnS quantum dots were deposited onto g-C3N4 nanosheets through an electrostatic self-assembly to form new nanocomposites (denoted as Mn-ZnS QDs@g-C3N4). Mn-ZnS QDs@g-C3N4 can emit a pair of complementary colour light, namely, orange room-temperature phosphorescence (RTP) at 582 nm and blue fluorescence at 450 nm. After 2,4,6-trinitrotoluene (TNT) dosing into Mn-ZnS QDs@g-C3N4 aqueous solution, and pairing with MEA to generate TNT anions capable of quenching the emission of Mn-doped ZnS QDs, the fluorescence colours of the solution changed from orange to blue across white, exhibiting unusual high-contrast fluorescence images. The developed ratiometric chemosensor showed very good linearity in the range of 0-12 µM TNT with a limit of detection of 0.56 µM and an RSD of 6.4 % (n = 5). Also, the ratiometric probe had an excellent selectivity for TNT over other nitroaromatic compounds, which was applied in the ratiometric test paper to image TNT in water, and TNT sensing under phosphorescence mode to efficiently avoid background interference. A high-contrast dual-emission platform for selective ratiometric detection of TNT was therefore established.

Poly-α, ß-d, l-Aspartyl-Arg-Gly-Asp-Ser-Based Urokinase Nanoparticles for Thrombolysis Therapy.

The most concerning adverse effects of thrombolytic agents are major bleeding and intracranial hemorrhage due to their short half-life, low fibrin specificity, and high dosage. To alleviate bleeding side effects during thrombolytic therapy which would bring about the risk of aggravation, we try to find a novel biodegradable delivery nanosystem to carry drugs to target the thrombus, reduce the dosage of the drug, and system side effects. A novel urokinase/poly-α, ß-d, l-aspartyl-Arg-Gly-Asp-Ser complex (UK/PD-RGDS) was synthesized and simply prepared. Its thrombolytic potency was assayed by the bubble-rising method and in vitro thrombolytic activity by the thrombus clot lysis assay separately. The in vivo thrombolytic activity and bleeding complication were evaluated by a rat model of carotid arteriovenous bypass thrombolysis. The thrombolytic potency (1288.19 ± 155.20 U/mg) of the UK/PD-RGDS complex nano-globule (18-130 nm) was 1.3 times that of commercial UK (966.77 ± 148.08 U/mg). In vivo, the UK/PD-RGDS complex (2000 IU/kg) could reduce the dose of UK by 90% while achieving the equivalent thrombolysis effect as the free UK (20,000 IU/kg). Additionally, the UK/PD-RGDS complex decreased the tail bleeding time compared with UK. The organ distribution of the FITC-UK/PD-RGDS complex was explored in the rat model. The UK/PD-RGDS complex could provide a promising platform to enhance thrombolytic efficacy significantly and reduce the major bleeding degree.

A new insight on the NO-CO reaction at the electronic level: homogeneous, E-R, and L-H mechanisms.

Carbonaceous surface, as one of the major carriers in coal combustion, was found to exert great influence on the nitric oxide with carbon monoxide (NO-CO) reaction. Although there have been some studies addressing the NO-CO reaction, the inherent mechanism remains obscure. In this work, some updated mechanisms with details were proposed at the electronic level. Using density functional theory calculations, the preferred pathways were identified with three channels consisting of homogeneous, Eley-Rideal (E-R), and Langmuir-Hinshelwood (L-H) heterogeneous reactions. The reasons for the difference in energy barrier among the three mechanisms were revealed by analyzing the chemical bond and electronic transfer. Results show that among these channels, the NO-CO reaction is more likely to occur along the E-R mechanism, due to its lower energy barrier of the rate-determining step. Compared to the L-H mechanism, there is a higher degree of electronic localization between NO molecules at the initial stage of the E-R mechanism. As a result, the NO dimer formation of the E-R mechanism has a lower energy barrier than that of the L-H mechanism. Meanwhile, a large number of electrons floods into the N-N, N-O, and O-O bonds of NO dimer in the homogeneous reaction, which certainly gets more difficult for the dissociation of O atoms in the gas phase. Accordingly, the following stage of N2 formation in the homogeneous reaction has a higher energy barrier than that in both the E-R and L-H reactions. Compared to the L-H mechanism, the E-R mechanism exhibits a lower degree of electronic localization between N2O and carbonaceous surface, suggesting that the interfacial interaction in the E-R mechanism is weaker. As a result, N2 is easier to remove from the carbonaceous surface in the E-R mechanism than in the L-H mechanism. To sum up, the results deepen the knowledge about the NO-CO reaction, which will help to further develop the oxy-fuel combustion technology.

Effects of 8-Amino-Isocorydine, a Derivative of Isocorydine, on Gastric Carcinoma Cell Proliferation and Apoptosis.

BACKGROUND: Isocorydine (ICD) has anticancer effects; however, its suboptimal bioactivity has driven the production of ICD derivatives, including 8-amino-isocorydine (8-NICD). OBJECTIVE: This study explored the antitumor effects of 8-NICD on a variety of tumor cell lines to detect tumors sensitive to 8-NICD and investigated the mechanisms by which it suppresses tumor cell growth. METHODS: Human gastric carcinoma (GC) cells (MGC-803) were used to evaluate the effects of 8-NICD on cell proliferation and apoptosis. The in vivo action of 8-NICD in a nude mouse xenograft model was also investigated. The antioxidant activity of 8-NICD was evaluated using a 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. RESULTS: 8-NICD exerted significant antitumor activity against several tumor cell lines with IC50 between 8.0 and 142.8 µM and was not toxic to healthy fibroblasts and epithelial cells at concentrations up to 100 µM. Moreover, 8-NICD strongly inhibited the proliferation of MGC803 cells without causing toxicity to human umbilical vein endothelial cells with a selectivity index of 19.2 and arrested MGC803 cells in the S phase. Further, the percentages of apoptotic MGC-803 and BGC823 cells increased in a concentration-dependent manner, and the expression of apoptosis regulator Bax increased, whereas that of Bcl-2 decreased in response to 8-NICD treatment. Further, 8-NICD significantly suppressed MGC-803 tumor growth in nude mice. In addition, 8-NICD was a potent scavenger of radicles in a 1,1-diphenyl-2-picrylhydrazyl (IC50 = 11.12 µM) antioxidant assay. CONCLUSIONS: These results suggest that 8-NICD exerts significant antitumor effects on GC cells by inducing apoptosis and cell cycle arrest and is a promising candidate anti-GC drug. The particularly high sensitivity of MGC803 cells suggest that the potential of 8-NICD to treat GC should be further explored. (Curr Ther Res Clin Exp. 2021; 82:XXX-XXX).

TTC36 inactivation induce malignant properties via Wnt-ß-catenin pathway in gastric carcinoma.

Objective: Tetratricopeptide repeat (TRP)-mediated cofactor proteins are involved in a wide range of cancers. TTC36 is little studied member of TRP subfamily. This study aimed to investigate the role of TTC36 in human gastric carcinoma (GC) and explore the potential underlying mechanisms. Methods: The analysis of TTC36 differential expression in GC was conducted using data from TCGA and a human tissue microarray. And effects of TTC36 expression on the prognosis of patients with gastric carcinoma were analyzed using the data from the GEO database. Lentivirus was transfected into the cell lines of AGS and BGC823 to construct overexpression and knocked down TTC36 cell model respectively. The effect of TTC36 expression on the growth, apoptosis and cell cycle of cells was explored in vitro. Downstream molecules were detected by western blotting. GSEA predicted signal pathway and related proteins were then detected. Results: TTC36 expression in human GC tissues was found significantly lower than that in adjacent normal tissues and closely related to clinical prognosis. The overexpression of TTC36 notably inhibited tumor progression, cell cycle G1/S transfer and increased apoptosis in AGS cells. Conversely, the opposite effects were observed when TTC36 was suppressed in BGC823 cells. The expression of cleaved caspase3, Survivin, cyclin D1 and c-Myc were consistent with the phenotype in TTC36 operated GC cell lines. Intriguingly, GSEA analysis predicted Wnt-ß-catenin pathway involved in TTC36 induced effects in GC cells, expression of ß-catenin and downstream molecules such as TCF4, c-jun and pAKT were found negative related to TTC36 expression in GC cells. Notably, treatment with the Wnt/ß-catenin inhibitor XAV939 dramatically attenuated the effects of TTC36 in GC cells. Conclusion: These results signify a critical role for TTC36 as a tumor suppressor in gastric carcinoma via regulating Wnt-ß-catenin pathway.

Effect of Atmospheres on Transformation of Heavy Metals during Thermal Treatment of MSWI Fly Ash: By Thermodynamic Equilibrium Calculation.

The vaporization behaviors of eight heavy metals (Pb, Zn, Cu, Cd, Cr, Co, Mn, and Ni) in municipal solid wastes incineration (MSWI) fly ash during thermal treatment under air atmosphere (21% O2/79% N2), an inert atmosphere (100% N2), and a reducing atmosphere (50% CO/50% N2) were evaluated based on a thermodynamic equilibrium calculation by FactSage 8.1. The results show that the reducing atmosphere promotes the melting of MSWI fly ash, resulting in a more liquid phase than in air or an inert atmosphere. Except for Cd, the formation of liquids can dissolve heavy metals and reduce their vaporization ratio. In the air and inert atmospheres, Pb, Zn, Cu, Co, Mn, and Ni vaporize mainly in the form of metallic chlorides, while Cd volatilizes in the form of metallic Cd (g) and CdO (g). In the reducing atmosphere, Co, Mn, and Ni still vaporize as chlorides. Zn and Cd mainly vaporize in the form of Zn (g) and Cd (g), respectively. In terms of Pb, in addition to its chlorides, the volatiles of Pb contain some Pb (g) and PbS (g). Cr has a low vaporization ratio, accounting for 2.4% of the air atmosphere. Cr, on the other hand, readily reacts with Ca to form water-soluble CrCaO4, potentially increasing Cr leaching. Except for Cd, the results of this study suggest that the reducing atmosphere is used for the thermal treatment of MSWI fly ash because it promotes the melting of fly ash and thus prevents heavy metal vaporization.

Alcohol Use in China: Unrecorded and Recorded Bai Jiu in Three Rural Regions.

In China, approximately 70% of beverage alcohol is consumed in the form of spirits. An estimated 25% of all alcohol consumed is unrecorded, mostly spirits (bai jiu), produced outside regulatory systems in small neighborhood distilleries, mostly in rural areas. Unrecorded bai jiu drinkers are generally older, male, prefer higher-strength bai jiu, and drink daily and mostly at home. To explore possible regional differences, researchers used interview data from 2919 bai jiu drinkers in rural areas in Hebei, Anhui, and Hubei provinces in China. Results confirmed that patterns varied by province. The sample in Hubei preferred unrecorded bai jiu with a more stable preference to alcohol type, tended to drink less frequently, and reported experiencing less drinking pressure, suggesting lower-risk drinking patterns in this region. The Hebei and Anhui sample reported higher frequency and greater amount of alcohol consumption, were more likely to experience drinking pressure, indicating higher-risk patterns in alcohol use in these two regions. The results provide needed details about regional differences in unrecorded bai jiu drinking patterns that are not evident in aggregated data and suggest variations in drinking patterns that may reflect local geography, local values, traditions, and ethnic differences.

[Quantitative Analysis of Pinellia ternata in Banxia Decoction by PCR].

Objective: To establish the quantitative detection method for Pinellia ternata in Banxia decoction by polymerase chain reaction( PCR) and to explore a suitable quantitative analysis method for medicinal materials in liquid preparation of traditional Chinese medicine. Methods: The PCR method was adopted for analyzing Pinellia ternata in Banxia decoction based on the specific detection of ITS region. The PCR amplification products were analyzed with agarose gel electrophoresis. The relationship between the percentage of Pinellia ternata in Banxia decoction with the PCR products were established. In addition,Real-Time PCR assay and agarose gel electrophoresis were applied in the quantitative detection. Results: Accurate quantitative analysis of Pinellia ternata medicinal materials can be achieved by two methods,and a better linear correlation in the standard curve( r = 0. 9943) were obtained with agarose gel electrophoresis method. Conclusion: A high specificity and sufficient reproducibility PCR technology with agarose gel eletroghoresis method has been established for the quantitative detection of Pinellia ternata in Banxia decoction. The quantitative detection of medicinal materials in decoction based on PCR technology was reported for the first time.

MiR-519d-3p suppresses invasion and migration of trophoblast cells via targeting MMP-2.

Our study was approved by the Medical Ethics Committee of Tang Du Hospital, Fourth Military Medical University and complied strictly with national ethical guidelines. Preeclampsia (PE) is a specific clinical disorder characterized by gestational hypertension and proteinuria and is a leading cause of maternal and perinatal mortality worldwide. The miR-519d-3p is upregulated in the maternal plasma of patients with PE which indicates a possible association between this microRNA and the pathogenesis of PE. No studies to date have addressed the effect of miR-519d-3p on the invasion and migration of trophoblast cells. In our study, we found that miR-519d-3p expression was elevated in placental samples from patients with PE. In vitro, overexpression of miR-519d-3p significantly inhibited trophoblast cell migration and invasion, whereas transfection of a miR-519d-3p inhibitor enhanced trophoblast cell migration and invasion. Luciferase assays confirmed that matrix metalloproteinase-2 (MMP-2) is a direct target of miR-519d-3p. Quantitative real-time PCR and western blot assays showed that overexpression of miR-519d-3p downregulated MMP-2 mRNA and protein expression. Knockdown of MMP-2 using a siRNA attenuated the increased trophoblast migration and invasion promoted by the miR-519d-3p inhibitor. In placentas from patients with PE or normal pregnancies, a negative correlation between the expression of MMP-2 and miR-519d-3p was observed using the Pearson correlation and linear regression analysis. Our present findings suggest that upregulation of miR-519d-3p may contribute to the development of PE by inhibiting trophoblast cell migration and invasion via targeting MMP-2; miR-519d-3p may represent a potential predictive and therapeutic target for PE.

[Study on the occurrence of ferrum in coal by ultrasound-assisted sequential chemical extraction].

To reveal the occurrence of Ferrum in coal, seven coal samples were selected according to the different contents of ferric oxide in the coal ash, and the content of Ferric element was determined by atomic absorption spectrophotometer (AAS) using nitric acid-perchloric acid-hydrofluoric acid wet digestion. Modes of occurrence of ferrium in the seven coal samples were studied by AAS using ultrasound-assisted sequential chemical extraction experiment (SCEE). Ultrasound promoted the contact of the extraction reagent with the coal particles and enhanced the dissolution process by producing characteristic acoustic cavitations, which greatly shortened the experimental time. The total amount of ferrium obtained by sequential extraction was approximate to the result of wet digestion, which indicated the procedure of SCEE was reasonable. The results showed that the ferric element mainly occurred in forms of carbonate state, Fe-Mn oxides state, sulfide state, sialic state and organic bound Fe in these coal samples. Among the various forms of these occurrences, the content of carbonate was the least, below 3.1%, while the content of sulfide was the dominant occurrence, ranging from 40% to 81.5%.

Evaluation of mercury speciation and removal through air pollution control devices of a 190 MW boiler.

Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction (SCR) and wet flue gas desulfurization (FGD) systems have the co-benefits of air pollutant and mercury removal. Configuration and operational conditions of APCDs and mercury speciation affect mercury removal efficiently at coal-fired utilities. The Ontario Hydro Method (OHM) recommended by the U.S. Environmental Protection Agency (EPA) was used to determine mercury speciation simultaneously at five sampling locations through SCR-ESP-FGD at a 190 MW unit. Chlorine in coal had been suggested as a factor affecting the mercury speciation in flue gas; and low-chlorine coal was purported to produce less oxidized mercury (Hg2+) and more elemental mercury (Hg0) at the SCR inlet compared to higher chlorine coal. SCR could oxidize elemental mercury into oxidized mercury when SCR was in service, and oxidation efficiency reached 71.0%. Therefore, oxidized mercury removal efficiency was enhanced through a wet FGD system. In the non-ozone season, about 89.5%-96.8% of oxidized mercury was controlled, but only 54.9%-68.8% of the total mercury was captured through wet FGD. Oxidized mercury removal efficiency was 95.9%-98.0%, and there was a big difference in the total mercury removal efficiencies from 78.0% to 90.2% in the ozone season. Mercury mass balance was evaluated to validate reliability of OHM testing data, and the ratio of mercury input in the coal to mercury output at the stack was from 0.84 to 1.08.

UV-visible spectroscopic study of the salicyladehyde benzoylhydrazone and its cobalt complexes.

Salicyladehyde benzoylhydrazone (SBH) has three groups suitable for forming coordination bond with transition metal. The UV-vis absorption spectra of SBH and its Co(II) complexes in various media were studied by using the deconvolution method. It is found that the structure of complex in solution is different from those in solid crystals. The nature of complexes in solution depends on acidity of the phenolic proton of SBH and on the medium. In neutral or slightly acid medium, the SBH is a non-charged bidentate ligand. And the "free" hydroxyl group on the SBH molecule makes it possible to form hydrogen bonds in solution. In basic medium, the SBH is a mono, negatively charged tridentates ligand.