Am J Respir Cell Mol Biol
June 2024
Small muscular pulmonary artery remodeling is a dominant feature of pulmonary arterial hypertension (PAH). PSEN1 affects angiogenesis, cancer, and Alzheimer's disease. We aimed to determine the role of PSEN1 in the pathogenesis of vascular remodeling in pulmonary hypertension (PH).
View Article and Find Full Text PDFThe phytochemicals in the peel of six oranges and ten mandarins including seven wild varieties and three cultivars were systematically characterised using UHPLC-Q-TOF-MS, and the correlation analysis was performed between phytochemicals and antioxidant capacity in order to investigate the phytochemical contributors to antioxidant capacity. The gradient elution was completed within 16 min and 92 compounds were undoubtedly or tentatively identified. Furthermore, the antioxidant capacities were determined using ABTS, DPPH and FRAP methods.
View Article and Find Full Text PDFAn efficient ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry method was developed for separation and profiling of phytochemical constituents of Chinese wild mandarin Mangshanju (Citrus reticulata Blanco). All constituents were well separated within 16 min. Based on retention times, accurate mass, MS fragments, and/or reference standards as well as databases, a total of 81 compounds were unambiguously identified or tentatively assigned including flavonoid glycosides, acylated flavonoid glycosides, flavones, polymethoxylated flavonoids, and limonoids as well as four other compounds.
View Article and Find Full Text PDFA rapid, sensitive, and efficient ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) method has been developed to analyze polymethoxylated flavonoids (PMFs) in 14 Citrus peels, including 7 Citrus reticulata (C. reticulata) and 7 Citrus sinensis (C. sinensis).
View Article and Find Full Text PDFThe human lens is comprised largely of crystallin proteins assembled into a highly ordered, interactive macro-structure essential for lens transparency and refractive index. Any disruption of intra- or inter-protein interactions will alter this delicate structure, exposing hydrophobic surfaces, with consequent protein aggregation and cataract formation. Cataracts are the most common cause of blindness worldwide, affecting tens of millions of people, and currently the only treatment is surgical removal of cataractous lenses.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
November 2014
The citrus process industry produces annually a huge amount of pomace, which is a rich source of citrus pectin. Here, we report the hydrogel of citrus pectin mediated by sodium hydroxide can be used to prepare fluorescent carbon dots (CDs). The introduction of hydrogel can not only make the temperature of the hydrothermal reaction down to 100 °C, but also avoid visually carbonized precipitates in the synthesis process even up to 180 °C.
View Article and Find Full Text PDFA label-free and sensitive fluorescence method for recognition of sequence-specific DNA using DNA-intercalating dye and metal-organic frameworks (MOFs) is developed. Here, MIL-101 (Cr3F(H2O)2O[(O2C)-C6H4-(CO2)]3·nH2O) is introduced as a quenching platform to decrease the high background fluorescence of SYBR Green I (SG)/probe DNA complex. Mechanism investigations show that MIL-101 can strongly adsorb the SG/probe DNA complex through π-π stacking and electrostatic interactions, and as a consequence, the fluorescence of the SG dye is greatly quenched.
View Article and Find Full Text PDFWe have developed a simple, rapid and label-free sensor for the essential biological OH radicals based on the fluorescence quenching of DNA-templated Ag nanoclusters (DNA-Ag NCs). The OH radicals generated from the Fenton reagent attack and cleave the DNA template, which disturbs the microenvironments around Ag NCs, resulting in spontaneous aggregation due to the lack of stabilization and further the quenching of the Ag NCs fluorescence. These changes in fluorescence intensity allow sensing of OH radicals with good sensitivity and selectivity under optimal conditions.
View Article and Find Full Text PDFIn this paper, a nanosized porous metal-organic framework, Fe-MIL-88NH₂, was facilely prepared with a uniform octahedral shape by the addition of acetic acid, and for the first time was demonstrated to possess intrinsic peroxidase-like activity. Kinetic analysis and electron spin resonance measurements indicated that the catalytic behavior was consistent with typical Michaelis-Menten kinetics and follows a ping-pong mechanism. As a novel peroxidase mimic material, Fe-MIL-88NH₂ shows the advantages of high catalytic efficiency, ultrahigh stability and high biocompatibility in aqueous medium compared with natural enzymes and other peroxidase nanomimetics.
View Article and Find Full Text PDFHere, a rapid, simple and sensitive method for visual detection of tetracycline antibiotics (TCs) was developed based on the turned on fluorescence induced by a metal-organic coordination polymer of Zn(bix) [bix=1,4-bis(imidazol-1-ylmethyl)benzene]. Tetracycline antibiotics, such as tetracycline hydrochloride (TC), doxycycline hyclate (DC), chlortetracycline hydrochloride (CTC) and oxytetracyline hydrochloride (OTC), showed very weak fluorescence in Tris-HCl buffer of pH 8.68-9.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
February 2013
Flavonoids such as naringenin and morin are ubiquitous in a wide range of foods isolated from plants, and have diverse effects on plants even on human health. Here, we establish a selective visual method for recognition of aringenin and morin based on the "switched on" fluorescence induced by a metal-organic coordination polymer of Zn(bix) [bix=1,4-bis(imidazol-1-ylmethyl)benzene]. Owing to the coordination interaction of aringenin and morin with Zn(II) from the polymeric structure of Zn(bix), the conformational free rotation of naringenin and morin is restricted leading to relatively rigid structures.
View Article and Find Full Text PDFPyrophosphate (PPi), as a biologically related phosphate anion, plays very important roles in organisms. Here, a highly selective visual method for distinction of PPi was made with commercial available 4-[(5-chloro-2-pyridyl)azo]-1,3-diaminobenzene (5-Cl-PADAB) in the presence of copper(II). The yellow solution of 5-Cl-PADAB exhibits strong absorption at 450.
View Article and Find Full Text PDFHighly selective sensing of cytidine triphosphate (CTP) against other triphosphate nucleosides including ATP, GTP and UTP is successfully achieved with a luminescent terbium(III)-organic framework (TbOF) of [Tb(2)(2,3-pzdc)(2)(ox)(H(2)O)(2)](n) (2,3-pzdc(2-) = 2,3-pyrazinedicarboxylate, ox(2-) = oxalate).
View Article and Find Full Text PDFAs one vital member among the family of phosphates, guanosine triphosphate (GTP) not only plays a very important role in many critical biological processes but also closely associates with definite pathological states. Based on the ratiometric fluorescence response of the zinc complex of 1,4-bis(imidazol-1-ylmethyl) benzene (bix) in this contribution, a highly selective recognition of GTP has been successfully developed. The fluorescence of bix-Zn(II) at 289 nm decreased in the presence of GTP with the appearance of one new emission band at 341 nm, resulting in ratiometric fluorescence changes with the concentration of GTP.
View Article and Find Full Text PDFA series of platinum(II) complexes bearing a chromophore-acceptor dyad obtained by reacting 4-(p-bromomethylphenyl)-6-phenyl-2,2'-bipyridine or 4'-(p-bromomethylphenyl)-2,2':6',2''-terpyridine with pyridine, 4-phenylpyridine, 4,4'-bipyridine, 1-methyl-4-(pyridin-4'-yl)pyridinium hexafluorophosphate respectively, were synthesized. Their photophysical properties, emission quenching studies by Pt nanoparticles and methyl viologen, electrochemical properties and photoinduced electron-transfer reactions in a photocatalytic hydrogen-generating system containing triethanolamine and colloidal Pt without an extra electron relay, were investigated. A comparison of the rates of hydrogen production for the two photocatalytic systems, one containing a metal-organic dyad and the other comprising a 1:1 mixture of the parental platinum(II) complexes and the corresponding electron relay, showed that intramolecular electron transfer improves the photocatalytic efficiency.
View Article and Find Full Text PDFPyrophosphate ion (PPi) is crucial in varieties of biological processes and industrial applications, and thus it is very important how to recognize it with high selectivity. In this contribution, one terpyridine (tpy)-based fluorescent molecule, 4-(methylphenyl)-2,2':6',2''-terpyridine (mptpy), has been reported to display a highly selective recognition for PPi in the presence of Zn(II). After exposure toward the Zn(II) ion, the characteristic emission of mptpy at 376 nm red-shifted to 406 nm with a strong enhancement upon an excitation at 280 nm, and then blue-shifted to 388 nm with the further addition of PPi.
View Article and Find Full Text PDFPyrophosphate (PPi) is involved in lots of anabolism and bioenergetic processes in organisms and possesses important biological functions so that its detection is very significant. Here, we developed a selective fluorometric detection method for PPi with a copper(II) complex of 2,6-bis(2-benzimidazolyl)pyridine (bbimp), and then applied it to the detection of bacterial alarmone ppGpp. bbimp has the fluorescence emission at 395 nm, but the bbimp-Cu(2+) complex is hardly fluorescent because the intrinsic fluorescence of bbimp is effectively quenched by Cu(2+).
View Article and Find Full Text PDFA simple method for phosphate (Pi) detection is established by developing an off-on fluorescence probe of europium-adjusted carbon dots (CDs), which has been successfully applied to the detection of Pi in very complicated matrixes such as artificial wetlands system.
View Article and Find Full Text PDFA simple, one-pot and controllable strategy is reported in this contribution for biomimetic synthesis and self-assembly of gold nanoparticles (Au-NPs). It involves our synthesized polyaldehyde dextran (PAD), which has been proved to be a biomacromolecule with excellent biocompatibility and biodegradability, acting as both a reducing agent and a stabilizer. The morphology of the as-prepared Au-NP assemblies can be controlled by adjusting the reaction conditions, such as the concentration of aldehyde in PAD, the reaction time and the temperature.
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