RESUMEN
Osteoporosis stands out as a prevalent skeletal ailment, prompting exploration into potential treatments, including dietary strontium ion supplements. This study assessed the efficacy of supplementation of three strontium forms-strontium citrate (SrC), strontium ranelate (SrR), and strontium chloride (SrCl)-for enhancing bone structure in 50 female SWISS mice, aged seven weeks. In total, 40 mice underwent ovariectomy, while 10 underwent sham ovariectomy. Ovariectomized (OVX) mice were randomly assigned to the following groups: OVX (no supplementation), OVX + SrR, OVX + SrC, and OVX + SrCl, at concentrations equivalent to the molar amount of strontium. After 16 weeks, micro-CT examined trabeculae and cortical bones, and whole-bone strontium content was determined. Results confirm strontium administration increased bone tissue mineral density (TMD) and Sr content, with SrC exhibiting the weakest effect. Femur morphometry showed limited Sr impact, especially in the OVX + SrC group. This research highlights strontium's potential in bone health, emphasizing variations in efficacy among its forms.
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Ácido Cítrico , Osteoporosis , Estroncio , Tiofenos , Femenino , Animales , Ratones , Densidad Ósea , Cloruros , Citratos , Osteoporosis/tratamiento farmacológico , Halógenos , Modelos Animales de EnfermedadRESUMEN
In this study, Fe0@Fe3O4 was synthesized and used to remove U(VI) from groundwater. Different experimental conditions and cycling experiments were used to investigate the performance of Fe0@Fe3O4 in the U(VI) removal, and the XRD, TEM, XPS and XANES techniques were employed to characterize the Fe0@Fe3O4. The results showed that the U(VI) removal efficiency of Fe0@Fe3O4 was 48.5 mg/g that was higher than the sum of removal efficiency of Fe0 and Fe3O4. The uranium on the surface of Fe0@Fe3O4 mainly existed as U(IV), followed by U(VI) and U(V). The Fe0 content decreased after reaction, while the Fe3O4 content increased. Based on the results of experiments and characterization, the enhanced removal efficiency of Fe0@Fe3O4 was attributed to the synergistic effect of Fe0 and Fe3O4 in which Fe3O4 accelerated the Fe0 corrosion that promoted the progressively formation of Fe(II) that promoted the reduction of adsorbed U(VI) to U(IV) and incorporated U(VI) to U(V). The performance of Fe0@Fe3O4 at near-neutrality condition was better than at acidic and alkalic conditions. The chloride ions, sulfate ions and nitrate ions showed minor effect on the Fe0@Fe3O4 performance, while carbonate ions exhibited significant inhibition. The metal cations showed different effect on the Fe0@Fe3O4 performance. The removal efficiency of Fe0@Fe3O4 decreased with the number of cycling experiment. Ionizing radiation could regenerate the used Fe0@Fe3O4. This study provides insight into the U(VI) removal by Fe0@Fe3O4 in aqueous solution.
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Hierro , Uranio , Agua , Cloruros , Halógenos , AdsorciónRESUMEN
Quenching is an important step to terminate disinfection during preparation of disinfected water samples for the analysis of disinfection byproducts (DBPs). However, an incomplete quenching might result in continued reactions of residual chlorine, whereas an excessive quenching might decompose target DBPs. Therefore, an adequate quenching to achieve simultaneous disinfection termination and DBP preservation is of particular importance. In this study, the two-stage reaction kinetics of chlorine and three commonly used quenching agents (i.e., ascorbic acid, sodium thiosulfate, and sodium sulfite) were determined. Stopping quenching during the first stage prevented interactions of residual chlorine with natural organic matter. Complete quenching was achieved by minimizing the quenching time for ascorbic acid and sodium sulfite, while limiting the quenching time to less than 3 min for sodium thiosulfate. At the optimized quenching times, the molar ratios (MRs) of quenching agent to chlorine were 1.05, 1.10, and 0.75 for ascorbic acid, sodium sulfite, and sodium thiosulfate, respectively. The destructive effects of the three quenching agents on total organic halogen (TOX) followed the rank order of ascorbic acid (33.7-64.8 %) < sodium sulfite (41.6-72.8 %) < sodium thiosulfate (43.3-73.2 %), and the destructive effects on aliphatic DBPs also followed the rank order of ascorbic acid (29.5-44.5 %) < sodium sulfite (34.9-51.9 %) < sodium thiosulfate (46.9-53.2 %). For total organic chlorine (TOCl) and aliphatic DBPs, the quenching behavior itself had more significant destructive effect than the quenching agent type/dose and quenching time, but for total organic bromine (TOBr), the destructive effect caused by quenching agent type/dose and quenching time was more significant. High-dose, long-duration quenching enhanced the reduction of TOX, but had little effect on aliphatic DBPs. Additionally, the three quenching agents reduced the levels of halophenols (except for tribromophenol), while maintained or increased the levels of tribromophenol, halobenzoic/salicylic acids, and halobenzaldehydes/salicylaldehydes. To achieve adequate quenching for overall DBP analysis in chlorinated water samples, it is recommended to use ascorbic acid at a quenching agent-to-chlorine MR of 1.0 for a quenching time of < 0.5 h.
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Desinfectantes , Agua Potable , Sulfitos , Tiosulfatos , Contaminantes Químicos del Agua , Purificación del Agua , Agua Potable/análisis , Cloro/análisis , Desinfectantes/análisis , Halógenos/análisis , Desinfección , Cloruros , Ácido Ascórbico/análisis , Contaminantes Químicos del Agua/análisis , HalogenaciónRESUMEN
The interaction between mercury (Hg) and inorganic compounds, including selenium (Se), sulfur (S), and halogens (X = Cl, Br, or I), plays a critical role in the global mercury cycle. However, most previously reported mercury compounds are susceptible to reduction, leading to the release of elemental mercury (Hg0) and causing secondary pollution. In this study, we unveil a groundbreaking discovery that underscores the vital role of halogenation in creating exceptionally stable Hg3Se2X2 compounds. Through the dynamic interplay of Hg, Se, and halogens, an intermediary stage denoted [HgSe]m[HgX2]n emerges, and this transformative process significantly elevates the stabilization of mercury. Remarkably, halogen ions strategically occupy pores at the periphery of HgSe clusters, engendering a more densely packed atomic arrangement of Hg, Se, and halogen components. A marked enhancement in both thermal and acid stability is observed, wherein temperatures ascend from 130 to 300 °C (transitioning from HgSe to Hg3Se2Cl2). This sequence of escalating stability follows the order HgSe < Hg3Se2I2 < Hg3Se2Br2 < Hg3Se2Cl2 for thermal resilience, complemented by virtually absent acid leaching. This innovative compound formation fundamentally alters the transformation pathways of gaseous Hg0 and ionic mercury (Hg2+), resulting in highly efficient in situ removal of both Hg0 and Hg2+ ions. These findings pave the way for groundbreaking advancements in mercury stabilization and environmental remediation strategies, offering a comprehensive solution through the creation of chemically stable precipitates.
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Compuestos de Mercurio , Mercurio , Selenio , Mercurio/química , Halogenación , Halógenos , Iones , Compuestos de Mercurio/químicaRESUMEN
The presented "PubChemQC B3LYP/6-31G*//PM6" data set is composed of the electronic properties of 85,938,443 molecules, encompassing a broad spectrum of molecules from essential compounds to biomolecules with a molecular weight up to 1000. These molecules account for 94.0% of the original PubChem Compound catalog as of August 29, 2016. The electronic properties, including orbitals, orbital energies, total energies, dipole moments, and other pertinent properties, were computed by using the B3LYP/6-31G* and PM6 methods. The data set, available in three formats, namely, GAMESS quantum chemistry program files, selected JSON output files, and a PostgreSQL database, provides researchers with the ability to query molecular properties. It is further subdivided into five subdata sets for more specific data. The first two subsets encompass molecules with carbon, hydrogen, oxygen, and nitrogen with molecular weights under 300 and 500, respectively. The third and fourth subsets incorporate molecules with carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur, fluorine, and chlorine, with molecular weights under 300 and 500, respectively. The fifth subset comprises molecules with carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur, fluorine, chlorine, sodium, potassium, magnesium, and calcium, with a molecular weight of under 500. The coefficients of determination for the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gap range from 0.892 (for CHON500) to 0.803 (for the whole data set). These comprehensive results pave the way for applications in drug discovery and materials science, among others. The data sets can be accessed under the Creative Commons Attribution 4.0 International license at the following web address: https://nakatamaho.riken.jp/pubchemqc.riken.jp/b3lyp_pm6_datasets.html.
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Cloro , Flúor , Halógenos , Carbono , Cloruros , Electrónica , Hidrógeno , Nitrógeno , Oxígeno , FósforoRESUMEN
Recently zero-dimensional (0-D) inorganic-organic metal halides (IOMHs) have become a promising class of optoelectronic materials. Herein, we report a new photoluminescent (PL) 0-D antimony(III)-based IOMH single crystal, namely [H2BPZ][SbCl5]·H2O (BPZ = benzylpiperazine). Photophysical characterizations indicate that [H2BPZ][SbCl5]·H2O exhibits singlet/triplet dual-band emission. Density functional theory (DFT) calculations suggest that [H2BPZ][SbCl5]·H2O has the large energy difference between singlet and triplet states, which might induce the dual emission in this compound. Temperature-dependent PL spectra analyses suggest the soft lattice and strong electron-phonon coupling in this compound. Thermogravimetric analysis shows that the water molecules in the lattice of the title crystal could be removed by thermal treatment, giving rise to a dehydrated phase of [H2BPZ][SbCl5]. Interestingly, such structural transformation is accompanied by a reversible PL emission transition between red light (630 nm, dehydrated phase) and yellow light (595 nm, water-containing phase). When being exposed to an environment with 77% relative humidity, the emission color of the dehydrated phase was able to change from red to yellow within 20 s, and the red emission could be restored after reheating. The red to yellow emission switching could be achieved in acetone with water concentration as low as 0.2 vol%. The reversible PL transition phenomenon makes [H2BPZ][SbCl5]·H2O a potential material for luminescent water-sensing.
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Calor , Hipertermia Inducida , Antimonio , Cloruros , Luminiscencia , HalógenosRESUMEN
Gaseous potassium (K) species play an important role in biomass combustion processes, and imaging techniques are powerful tools to investigate the related gas-phase chemistry. Here, laser absorption imaging of gaseous atomic K in flames is implemented using tunable diode laser absorption spectroscopy at 769.9 nm and a high-speed complementary metal oxide semiconductor (CMOS) camera recording at 30 kfps. Atomic K absorption spectra are acquired for each camera pixel in a field of view of 28 × 28 mm at a rate of 100 Hz. The technique is used to determine the spatial distribution of atomic K concentration during the conversion of potassium chloride (KCl) salt and wheat straw particles in a laminar premixed CH4/air flame with an image pixel resolution of up to 120 µm. Due to axisymmetry in setup geometry and, consequently, atomic K distributions, the radial atomic K concentration fields could be reconstructed by one-dimensional tomography. For the KCl sample, the K concentration field was in excellent agreement with previous point measurements. In the case of wheat straw, atomic K concentrations of around 3 ppm were observed in a cylindrical flame during devolatilization. In the char conversion phase, a spherical layer of atomic K, with concentrations reaching 25 ppm, was found within 5 mm of the particle surface, while the concentration rapidly decreased to sub-ppm levels along the vertical axis. In both cases, a thin (â¼1 mm) layer without any atomic K was observed in close vicinity to the particle, suggesting that the potassium was initially not released in its atomic form.
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Cloruros , Potasio , Cloruro de Potasio , Biomasa , Gases , Cloruro de Sodio , Láseres de Semiconductores , Halógenos , TomografíaRESUMEN
Halogen bonding to phosphorus atoms remains uncommon, with relatively few examples reported in the literature. Here, the preparation and investigation of the cocrystal bis(dicyclohexylphenylphosphine)(1,6-diiodoperfluorohexane) by X-ray crystallography and solid-state multinuclear magnetic resonance spectroscopy is described. The crystal structure features two crystallographically unique C-I...P halogen bonds [dI...P = 3.090â (5)â Å, 3.264â (5)â Å] and crystallographic disorder of one of the 1,6-diiodoperfluorohexane molecules. The first of these is the shortest and most linear I...P halogen bond reported to date. 13C, 19F, and 31P magic angle spinning solid-state NMR spectra are reported. A 31P chemical shift change of -7.0 p.p.m. in the cocrystal relative to pure dicyclohexylphenylphosphine, consistent with halogen bond formation, is noted. This work establishes iodoperfluoroalkanes as viable halogen bond donors when paired with phosphorus acceptors, and also shows that dicyclohexylphenylphosphine can act as a practical halogen bond acceptor.
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Halógenos , Yodo , Cristalografía por Rayos X , Halógenos/química , Enlace de Hidrógeno , Yoduros/química , Espectroscopía de Resonancia Magnética , Resonancia Magnética Nuclear Biomolecular , Fósforo , Rayos XRESUMEN
Almost all conventional drug discovery research has been based on hydrocarbon-based frameworks and common chemical elements such as nitrogen, oxygen, sulfur, and the halogens. However, triggered by the approval of bortezomib, a boronic acid-containing pharmaceutical agent, the incorporation of functionalities that are not native in biological systems has been intensively investigated. Several other boron-containing pharmaceuticals have also been marketed. Therefore, the inclusion of various elements is one of the most promising strategies for the development of novel and distinctive drug candidates. In this symposium review, the author focused on the 'elements chemistry' approaches for the structural development of biologically active compounds, particularly those involving silicon and phosphorus. The isosteric exchange of Si and C (Si/C-exchange) is one of the most-investigated forms of substituting elements. We revealed the detailed physicochemical impact of Si/C-exchange, and we proposed several applications of silyl functionalities other than the simple Si/C-exchange. Regarding phosphorus, we recently revealed that the P-B substructure can function as the isostere of C-C or Si-C substructures. In addition to these isosteric exchanges, the development of biologically active compounds bearing unique substructures such as carboranes, hydrophobic boron clusters, and ferrocene is introduced. These novel strategies provide several options for structural development, offering great potential for expanding the chemical space of medicinal chemistry.
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Bortezomib/síntesis química , Química Farmacéutica/métodos , Diseño de Fármacos/métodos , Descubrimiento de Drogas/métodos , Elementos Químicos , Hidrocarburos/química , Bortezomib/química , Fenómenos Químicos , Química Farmacéutica/tendencias , Halógenos/química , Nitrógeno/química , Oxígeno/química , Fósforo/química , Silicio/química , Azufre/químicaRESUMEN
Peroxides in edible oils, whose amounts are measured using the peroxide value, are closely related to human health. Long-term consumption of edible oils with high peroxide values can lead to a variety of human diseases, which highlights the significance of examining oil types and their corresponding peroxide values. For identifying a wide range of edible oils, we established a colorimetric sensor array based on the halogen ion exchange between CsPbBr3 and two iodides (octadecylammonium iodide (ODAI) and ZnI2). Different kinds of edible oils contain distinct peroxidic substances that have the distinct ability to oxidize iodides. After specific types of edible oils react with excess iodides (ODAI and ZnI2), different amounts of residual iodides are left for further halogen exchange with CsPbBr3, resulting in various colorimetric responses, measured in RGB (red/green/blue) values, under fluorescent light. Based on RGB pattern analysis as fingerprints using two anion exchangers (ODAI and ZnI2), our proposed colorimetric sensor array was proved by linear discriminant analysis (LDA) to have an ability to accurately distinguish edible oils at a minimal volumetric concentration of 6.67% in seven real samples.
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Colorimetría , Yoduros , Halógenos , Humanos , Intercambio Iónico , Aceites de PlantasRESUMEN
BACKGROUND: Granny Smith (GS) apple has low protein content and poor antimicrobial properties; hence it has been blended with Aloe vera (AV; high ascorbic acid, antimicrobial and antioxidant properties) and soybean flour (SF; rich in phenols, flavonoids, ascorbic acid, total antioxidant and protein) in different proportions to obtain fortified GS, i.e. GSAVSF. Moreover, GS being a perishable fruit, its moisture content should be reduced to enhance shelf life. Accordingly, this GSAVSF was osmotically pre-dehydrated and finally dried through energy-efficient quartz-halogen radiation (QHR) assisted vacuum-drying (QHRVD) to produce dried GSAVSF i.e. (DGSAVSF) under optimized conditions. RESULTS: The optimally dehydrated DGSAVSF product resulted in minimum moisture (4.85% w/w) and maximum protein (6.24 g kg-1 ) content. The application of osmotic dehydration and QHRVD afforded acceptable colour of DGSAVSF compared to GSAVSF (ΔEI * = 10.07 ± 0.21). A parametric drying model was formulated that corroborated well with Fick's equation. QHRVD rendered high moisture diffusivity (1.49 × 10-8 m2 s-1 ) and low activation energy (27.64 kJ mol-1 K-1 ). Appreciable quality improvements with respect to fresh GS concerning ascorbic acid (176.05%), total phenolic (579.07%), total flavonoid (333.33%) contents and 2,2'-diphenyl-1-picrylhydrazyl radical scavenging activity (446.71%) could be achieved. The product demonstrated satisfactory shelf life (1 × 104 CFU g-1 : aerobic mesophilic; 1 × 104 CFU g-1 : mould and yeast) and high rehydration ratio (4.25 ± 0.1). CONCLUSION: The enrichment of GS with AV and SF along with optimal drying protocols could provide a quality fortified DGSAVSF through an energy-proficient sustainable process. The highly nutritious product with suitable colour, microbial stability and rehydration ratio also satisfied a 9-point hedonic scale, thus confirming consumer acceptability. © 2020 Society of Chemical Industry.
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Aloe/química , Desecación/métodos , Harina/análisis , Conservación de Alimentos/métodos , Glycine max/química , Halógenos/química , Malus/química , Cuarzo/química , Desecación/instrumentación , Conservación de Alimentos/instrumentación , Alimentos Fortificados/análisis , Frutas/química , Cinética , VacioRESUMEN
Iodothyronine deiodinases (Dios) are important selenoproteins that control the concentration of the active thyroid hormone (TH) triiodothyronine through regioselective deiodination. The X-ray structure of a truncated monomer of Type III Dio (Dio3), which deiodinates TH inner rings through a selenocysteine (Sec) residue, revealed a thioredoxin-fold catalytic domain supplemented with an unstructured Ω-loop. Loop dynamics are driven by interactions of the conserved Trp207 with solvent in multi-microsecond molecular dynamics simulations of the Dio3 thioredoxin(Trx)-fold domain. Hydrogen bonding interactions of Glu200 with residues conserved across the Dio family anchor the loop's N-terminus to the active site Ser-Cys-Thr-Sec sequence. A key long-lived loop conformation coincides with the opening of a cryptic pocket that accommodates thyroxine (T4) through an Iâ¯Se halogen bond to Sec170 and the amino acid group with a polar cleft. The Dio3-T4 complex is stabilized by an Iâ¯O halogen bond between an outer ring iodine and Asp211, consistent with Dio3 selectivity for inner ring deiodination. Non-conservation of residues, such as Asp211, in other Dio types in the flexible portion of the loop sequence suggests a mechanism for regioselectivity through Dio type-specific loop conformations. Cys168 is proposed to attack the selenenyl iodide intermediate to regenerate Dio3 based upon structural comparison with related Trx-fold proteins.
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Química Computacional/métodos , Yoduro Peroxidasa/metabolismo , Tiroxina/química , Tiroxina/metabolismo , Halógenos/química , Enlace de Hidrógeno , Yoduro Peroxidasa/química , Yoduro Peroxidasa/fisiología , Conformación Molecular , Selenocisteína , Selenoproteínas/metabolismo , Selenoproteínas/fisiología , Transducción de Señal , Hormonas Tiroideas , Triyodotironina/metabolismoRESUMEN
An eco-friendly biosynthesized Pd NP anchored Thymbra spicata extract-modified graphene oxide (Pd NPs/rGO-T. spicata) nanohybrid material has been introduced. Initially, the herb, Thymbra spicata extract was immobilized on the surface of GO via their natural adhering capability. The polyphenolic function grafted in situ prepared RGO acted as the natural reductant of Pd precursor. The as-prepared nanocomposite (Pd NPs/rGO-T. spicata) was characterized using Fourier transform infrared (FTIR), UV-vis, X-ray diffraction (XRD), inductively coupled plasma (ICP), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), high resolution transmission electron microscopy (HRTEM), Fast Fourier Transform (FFT), Raman spectroscopy and EDX elemental mapping techniques. It has been observed that the Pd NPs with perfect crystal structure, uniform shape and size were dispersed homogeneously on the rGO surface. The material showed excellent water dispersibility due to the hydrophilicity of biomolecules attached over them, which is very essential in heterogeneous catalysis. The T. spicata contained biomolecules served as effective capping, reducing and stabilizing agents for the uniform immobilization of Pd precursors on graphene sheet surface without aggregation. The catalytic activity of this nano hybrid was assessed comprehensively in the cyanation of aryl halides with a wide range of substrates using K4[Fe(CN)6] as a cheap source of cyanide. The model reaction resulted outstanding catalytic performance with a great reusability of the catalysis.
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Cianuros/química , Grafito/química , Halógenos/química , Nanopartículas del Metal/química , Paladio/química , Extractos Vegetales/química , Catálisis , Lamiaceae/ultraestructura , Nanopartículas del Metal/ultraestructura , Espectrometría por Rayos X , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Difracción de Rayos XRESUMEN
Continuous QSAR models have been developed and validated for the prediction of no-observed-adverse-effect (NOAEL) in rats, using training and test sets from the Fraunhofer RepDose® database and EFSA's Chemical Hazards Database: OpenFoodTox. This paper demonstrates that the HARD index, as an integrated attribute of SMILES, improves the prediction power of NOAEL values using the continuous QSAR models and Monte Carlo simulations. The HARD-index is a line of eleven symbols, which represents the presence, or absence of eight chemical elements (nitrogen, oxygen, sulfur, phosphorus, fluorine, chlorine, bromine, and iodine) and different kinds of chemical bonds (double bond, triple bond, and stereo chemical bond). Optimal molecular descriptors calculated with the Monte Carlo technique (maximization of correlation coefficient between the descriptor and endpoint) give satisfactory predictive models for NOAEL. Optimal molecular descriptors calculated in this way with the Monte Carlo technique (maximization of correlation coefficient between the descriptor and endpoint) give amongst the best results available in the literature. The models are built up in accordance with OECD principles.
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Modelos Químicos , Nivel sin Efectos Adversos Observados , Programas Informáticos , Animales , Simulación por Computador , Bases de Datos Factuales , Halógenos/química , Método de Montecarlo , Nitrógeno/química , Oxígeno/química , Fósforo/química , Relación Estructura-Actividad Cuantitativa , Ratas , Azufre/químicaRESUMEN
OBJECTIVES: This systematic review (PROSPERO register: CRD42016053140) investigated the influence of different types of light on the pulp tissue during dental bleaching. MATERIALS AND METHODS: Two independent authors conducted a systematic search and risk of bias evaluations. An electronic search was undertaken (PubMed/Medline, Embase, The Cochrane Library, and other databases) until May 2017. The population, intervention, comparison, outcomes (PICO) question was: "Does the light in dental bleaching change the response of the pulp to the bleaching procedure?" The intervention involved pulp tissue/cells after bleaching with light, while the comparison involved pulp tissue/cells after bleaching without light. The primary outcome was the inflammation/cytotoxicity observed in pulp after bleaching. RESULTS: Out of 2210 articles found, 12 articles were included in the review; four were in vivo studies (one study in dogs/others in human), and eight were in vitro studies (cell culture/with artificial pulp chamber or not). The light source used was halogen, light-emitting diode (LED), and laser. Only one in vivo study that used heat to simulate light effects showed significant pulp inflammation. Only two in vitro studies demonstrated that light influenced cell metabolism; one using halogen light indicated negative effects, and the other using laser therapy indicated positive effects. Given that animal and in vitro studies have been identified, there remain some limitations for extrapolation to the human situation. Furthermore, different light parameters were used. CONCLUSIONS: The effects of dental bleaching on the pulp are not influenced by different types of light, but different light parameters can influence these properties. CLINICAL RELEVANCE: There is insufficient evidence about the influence of different types of light on inflammation/cytotoxicity of the pulp.
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Luces de Curación Dental , Pulpa Dental/efectos de los fármacos , Pulpa Dental/efectos de la radiación , Terapia por Luz de Baja Intensidad , Blanqueadores Dentales/uso terapéutico , Blanqueamiento de Dientes/métodos , Animales , Perros , Halógenos , HumanosRESUMEN
The endophytic fungus, Dothideomycete sp. CRI7, isolated from the terrestrial plant, Tiliacora triandra, was salt tolerant, capable of growing in the culture medium prepared from seawater; salts in seawater did not have any effects on the fungal growth. Metabolite productions of the fungus CRI7 cultivated in media prepared from seawater (MSW), prepared from deionized water supplemented with potassium bromide (MKBr) or potassium iodide (MKI), and prepared from deionized water (MDW) were investigated. It was found that the cultivation of the fungus CRI7 in MKBr and MSW enabled the fungus to produce nine new metabolites (1-9). The production of an azaphilone, austdiol (10), of the fungus CRI7 grown in MDW was 0.04g/L, which was much lower than that grown in MSW, MKBr, and MKI media which provided the yields of 0.5, 0.9, and 1.2g/L, respectively, indicating that halogen salts significantly enhanced the production of the polyketide 10. The cultivation of terrestrial fungi in media containing halogen salts could therefore be useful for the metabolite diversification by one strain-many compounds (OSMAC) approach. Moreover, the isolated polyketides had significant biosynthetic relationship, suggesting that the cultivation of fungi in halogen containing media could provide the insights into certain polyketide biosynthesis. One of the isolated compounds exhibited antibacterial activity with the MIC value of 100µg/mL.
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Ascomicetos/metabolismo , Medios de Cultivo/química , Halógenos/química , Agua de Mar/química , Ascomicetos/crecimiento & desarrolloRESUMEN
Speciation analysis has become an invaluable tool in human health risk assessment, environmental monitoring or food quality control. Another step is to develop reliable multielemental speciation methodologies, to reduce costs, waste and time needed for the analysis. Separation and detection of species of several elements in a single analytical run can be accomplished by high performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC/ICP-MS). Our review assembles articles concerning multielemental speciation determination of: As, Se, Cr, Sb, I, Br, Pb, Hg, V, Mo, Te, Tl, Cd and W in environmental, biological, food and clinical samples analyzed with HPLC/ICP-MS. It addresses the procedures in terms of following issues: sample collection and pretreatment, selection of optimal conditions for elements species separation by HPLC and determination using ICP-MS as well as metrological approach. The presented work is the first review article concerning multielemental speciation analysis by advanced hyphenated technique HPLC/ICP-MS.
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Arsénico/análisis , Halógenos/análisis , Metales/análisis , Selenio/análisis , Animales , Cromatografía Líquida de Alta Presión/métodos , Contaminantes Ambientales/análisis , Humanos , Espectrometría de Masas/métodosRESUMEN
Thiourea derivatives have drawn much attention for their latent capacities of biological activities. In this study, we designed acylthiourea compounds as polo-like kinase 1 (Plk1) polo-box domain (PBD) inhibitors. A series of acylthiourea derivatives without pan assay interference structure (PAINS) were synthesized. Four compounds with halogen substituents exhibited binding affinities to Plk1 PBD in low micromole range. The most potent compound (3v) showed selectivity over other subtypes of Plk PBDs and inhibited the kinase activity of full-length Plk1.
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Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/química , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/química , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/química , Tiourea/química , Tiourea/farmacología , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Halógenos/química , Células HeLa , Humanos , Simulación del Acoplamiento Molecular , Dominios Proteicos , Inhibidores de Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Especificidad por Sustrato , Tiourea/metabolismo , Quinasa Tipo Polo 1RESUMEN
Drug repositioning has been attracting increasingly attention for its advantages of reducing costs and risks. Statistics showed that around one quarter of the marketed drugs are organohalogens. However, no study has been reported, to the best of our knowledge, to aim at efficiently repositioning organohalogen drugs, which may be attributed to the lack of accurate halogen bonding scoring function. Here, we present a study to show that two organohalogen drugs were successfully repositioned as potent B-Raf V600E inhibitors via molecular docking with halogen bonding scoring function, namely D(3)DOCKxb developed in our lab, and bioassay. After virtual screening by D(3)DOCKxb against the database CMC (Comprehensive Medicinal Chemistry), 3 organohalogen drugs that were predicted to form strong halogen bonding with B-Raf V600E were purchased and tested with ELISA-based assay. In the end, 2 of them, rafoxanide and closantel, were identified as potent inhibitors with IC50 values of 0.07 µM and 1.90 µM, respectively, which are comparable to that of vemurafenib (IC50: 0.17 µM), a marketed drug targeting B-Raf V600E. Single point mutagenesis experiments confirmed the conformations predicted by D(3)DOCKxb. And comparison experiment revealed that halogen bonding scoring function is essential for repositioning those drugs with heavy halogen atoms in their molecular structures.
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Reposicionamiento de Medicamentos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Sustitución de Aminoácidos , Evaluación Preclínica de Medicamentos , Halógenos/química , Halógenos/farmacocinética , Halógenos/farmacología , Humanos , Técnicas In Vitro , Simulación del Acoplamiento Molecular , Estructura Molecular , Mutagénesis Sitio-Dirigida , Compuestos Orgánicos/química , Compuestos Orgánicos/farmacocinética , Compuestos Orgánicos/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Rafoxanida/química , Rafoxanida/farmacocinética , Rafoxanida/farmacología , Salicilanilidas/química , Salicilanilidas/farmacocinética , Salicilanilidas/farmacología , Interfaz Usuario-ComputadorRESUMEN
A novel series of CD1d ligand α-galactosylceramides (α-GalCers) were synthesized by incorporation of the heavy atoms Br and Se in the acyl chain backbone of α-galactosyl-N-cerotoylphytosphingosine. The synthetic analogues are potent CD1d ligands and stimulate mouse invariant natural killer T (iNKT) cells to selectively enhance Th1 cytokine production. These synthetic analogues would be efficient X-ray crystallographic probes to disclose precise atomic positions of alkyl carbons and lipid-protein interactions in KRN7000/CD1d complexes.