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1.
Curr Pharm Des ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38798216

RESUMO

MicroRNAs (miRNAs) are non-coding RNA molecules that bind to mRNAs to regulate gene expression. Since changes in miRNA expression levels have been found in a variety of autoimmune illnesses, miRNAs are important in autoimmune diseases. MiRNAs serve not only as pathogenic factors and biomarkers for autoimmune diseases but also as important targets for disease therapeutics. Although miRNA-based treatments are still in the research stage, in-depth investigations into the biological functions of miRNAs have significantly enhanced our understanding of their mechanisms in autoimmune diseases. The purpose of this review is to summarize the biological functions of miRNAs, their roles in rheumatoid arthritis and systemic lupus erythematosus, therapeutic strategies, and challenges.

2.
Inorg Chem ; 62(32): 12730-12740, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37529894

RESUMO

The construction of attractive dual-functional lanthanide-based metal-organic frameworks (Ln-MOFs) with ratiometric fluorescent detection and proton conductivity is significant and challenging. Herein, a three-dimensional (3D) Eu-MOF, namely, [Eu4(HL)2(SBA)4(H2O)6]·9H2O, has been hydrothermally synthesized with a dual-ligand strategy, using (4-carboxypiperidyl)-N-methylenephosphonic acid (H3L = H2O3PCH2-NC5H9-COOH) and 4-sulfobenzoic acid monopotassium salt (KHSBA = KO3SC6H4COOH) as organic linkers. Eu-MOF showed ratiometric fluorescent broad-spectrum sensing of benzophenone-like ultraviolet filters (BP-like UVFs) with satisfactory sensitivity, selectivity, and low limits of detection in water/ethanol (1:1, v/v) solutions and real urine systems. A portable test paper was prepared for the convenience of actual detection. The potential sensing mechanisms were thoroughly analyzed by diversified experiments. The synergistic effect of the forbidden energy transfer from the ligand to Eu3+, the internal filtration effect (IFE), the formation of a complex, and weak interactions between the KHSBA ligand and BP-like UVFs is responsible for the ratiometric sensing effect. Meanwhile, Eu-MOF displayed relatively high proton conductivity of 2.60 × 10-4 S cm-1 at 368 K and 95% relative humidity (RH), making it a potential material for proton conduction. This work provides valuable guidance for the facile and effective design and construction of multifunctional Ln-MOFs with promising performance.

3.
Int J Biol Macromol ; 237: 124216, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36990414

RESUMO

A hyphenated process, autoclaving followed by ultrasonication (AU), was evaluated for efficient extraction of polysaccharides (PS) from Lentinula edodes (Shiitake) mushroom. The PS yield (w/w) was 8.44 % from hot-water extraction (HWE), 11.01 % by autoclaving extraction (AE), and 16.3 % by AUE. The AUE water extract was subject to fractional precipitation in four-steps with increasing ethanol concentration of 40 %, 50 %, 70 % and 80 % (v/v), yielding four PS fractions in descending molecular weight (MW), PS40 > PS50 > PS70 > PS80. All the four PS fractions were composed of four monosaccharide residues, mannose (Man), glucose (Glc) and galactose (Gal) but in different mole ratios. The PS40 fraction with the highest average MW (4.98 × 106) was the most abundant fraction, accounting for 64.4 % of the total PS mass and also had the highest glucose molar ratio (~80 %). PS40 also most significantly enhanced the NO, and ROS generation and phagocytic activity in RAW 264.7 cells. The results proved that AUE followed by fractional ethanol precipitation is an efficient strategy with reduced solvent expenditure for isolation of the major immunostimulatory PS from L. edodes mushroom.


Assuntos
Cogumelos Shiitake , Humanos , Cogumelos Shiitake/química , Precipitação Fracionada , Polissacarídeos/química , Água , Glucose , Etanol
4.
Inorg Chem ; 61(49): 20111-20122, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36424127

RESUMO

Construction and investigation of dual-functional metal-organic frameworks (MOFs) with luminescent sensing and proton conduction provide widespread applications in clean energy and environmental monitoring fields. By selecting a phosphonic acid ligand 4-pyridyl-CH2N(CH2PO3H2)2 (H4L) and coligand 2,2'-biimidazole (H2biim), two cadmium-based MOFs [Cd1.5(HL)(H2biim)0.5] (1) and (H4biim)0.5·[Cd2(L)(H2biim)Cl] (2) with different structures and properties have been hydrothermally synthesized by controlling reaction temperature. Based on the excellent thermal and chemical stabilities, and good luminescent stabilities in water solution, 1 and 2 can serve as luminescent sensors of chloramphenicol (CAP) with different quenching constant (KSV) values and detection limits (LODs) in water, simulated environmental system, and real fish water system. Meanwhile, different sensing effects and possible sensing mechanisms are analyzed in detail. Moreover, 1 and 2 can also serve as good proton-conducting materials. The proton conductivities can reach up to 1.41 × 10-4 S cm-1 for 1 and 1.02 × 10-3 S cm-1 for 2 at 368 K and 95% relative humidity (RH). Among them, 2 shows better luminescent sensing and proton conduction performance than 1, which indicates that different crystal structures have a great impact on the properties of MOFs. Through the discussion of the relationship between structures and properties in detail, the possible reasons for the differences in properties are obtained, which can provide theoretical guidance for the rational design of this kind of dual-functional MOFs in the future.


Assuntos
Estruturas Metalorgânicas , Animais , Prótons , Antibacterianos , Cádmio , Água
5.
Inorg Chem ; 60(22): 17303-17314, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34699193

RESUMO

It remains a challenge to exploit dual-functional metal-organic frameworks (MOFs) for applications, including luminescence detection and proton conduction. With the deliberate selection of the bifunctional organic ligand 5-sulfoisophthalic acid monosodium salt (NaH2bts), and the phosphonic acid ligand N,N'-piperazine (bismethylenephosphonic acid; H4L), a robust three-dimensional (3D) noninterpenetrating dual-functional MOF, [Tb(H2L)(H2bts)(H2O)]·H2O (1), has been synthesized hydrothermally. On the basis of the excellent thermal and chemical as well as superior luminescence stabilities in water and solutions with different pHs, 1 can serve as the simple, rapid, and highly selective and sensitive luminescence detection of the carcinoid biomarkers 5-hydroxytryptamine (HT) and its metabolite 5-hydroxyindole-3-acetic acid (HIAA) with detection limits of nanomolar magnitude in water and in simulated blood plasma and urine systems. Due to the change in the signals that could be readily differentiated by the naked eye under a UV lamp, a portable test paper has been developed. The probable quenching mechanisms are discussed in detail. In addition, a great number of hydrogen-bonding networks are formed among the uncoordinated carboxylic oxygen atoms, sulfonate oxygen atoms, protonated nitrogen atoms, and water molecules, which provide potential proton-hopping sites for proton conduction, leading to a maximum proton conductivity of 2.3 × 10-4 S cm-1 at 368 K and 95% relative humidity. The above results suggest that rationally designed dual-functional MOFs can open an avenue for the development of occupational diagnostic tools and alternative energy technology.


Assuntos
Tumor Carcinoide/química , Luminescência , Estruturas Metalorgânicas/química , Prótons , Biomarcadores/análise , Estruturas Metalorgânicas/síntese química , Modelos Moleculares
6.
Biochem Biophys Res Commun ; 506(4): 874-882, 2018 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-30392910

RESUMO

Serum transferrin (tf), encoding an iron-binding glycoprotein, has been revealed to play important roles in iron transportation and immune response, and it also has been demonstrated to be valuable for phylogenetic analysis in vertebrates. However, the evolutionary conservation, expression profiles and positive selection of transferrin genes among freshwater turtle species remain largely unclear. Here, the genomic DNA and coding sequences of transferrin genes were cloned and characterized in seven freshwater turtles including Mauremys mutica, Mauremys sinensis, Cyclemys dentate, Mauremyssi reevesi, Heosemys grandis, Trachemys scripta and Chrysemys picta. The isolated coding sequences of turtles' tf genes were 2118 bp or 2121 bp, encoding 706 or 707 amino acids. The predicted Tf proteins of turtles share high identities with M. mutica Tf, up to 91%-98% and the M. mutica Tf has the highest identity (91%) in amino acid with the Chelomia mydas Tf, the moderate with other reptiles' Tfs (65%-59%), chicken (58%), and Human Tf (∼55%), and the lowest with zebrafish Tf (41%). Additionally, tf genes were consistently composed of 17 exons and 16 introns with the same splicing sites in introns in all the turtles examined. Moreover, 12 positive selected sites were detected in these turtles' Tf and mainly distributed on the surface of transferrin protein. Importantly, it was found that transferrin genes in all turtles examined were predominantly expressed in adult liver via real-time quantitative PCR. The molecular characterizations and expression profiles of transferrin would shed new insights into understanding the conversations and divergences of transferrin genes in turtles, even in vertebrates.


Assuntos
Evolução Molecular , Água Doce , Regulação da Expressão Gênica , Genoma , Transferrina/genética , Tartarugas/genética , Sequência de Aminoácidos , Animais , Teorema de Bayes , Clonagem Molecular , DNA Complementar/genética , Éxons , Íntrons , Modelos Moleculares , Especificidade de Órgãos/genética , Seleção Genética , Transferrina/química
7.
ACS Omega ; 3(12): 16443-16452, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31458280

RESUMO

Two luminescent lead phosphonates with two-dimensional (2D) layer and three-dimensional (3D) framework structure, namely, Pb3[(L1)2(Hssc)(H2O)2] (1) and [Pb2(L2)0.5(bts)(H2O)2]·H2O (2) (H2L1 = O(CH2CH2)2NCH2PO3H2, H4L2 = H2PO3CH2NH(C2H4)2NHCH2PO3H2, H3ssc = 5-sulfosalicylic acid, NaH2bts = 5-sulfoisophthalic acid sodium) have been prepared via hydrothermal techniques. The two compounds not only show excellent thermal stability but also remain intact in aqueous solution within an extensive pH range. Moreover, the atomic absorption spectroscopy analysis experiment indicates that there does not exist the leaching of Pb2+ ions from the lead phosphonates, which show they are nontoxic in aqueous solution. In compound 1, the Pb(1)O4, Pb(2)O7, Pb(3)O4, and CPO3 polyhedra are interlinked into a one-dimensional chain, which is further connected to adjacent chain by sharing the Hssc2- to form a 2D layer. Interestingly, compound 1 as a highly selective and sensitive luminescent material can be used to detect the thymine molecule with a very low detection limit of 8.26 × 10-7 M. In compound 2, the Pb(1)O6 and Pb(2)O5 polyhedra are interlinked into a dimer via edge sharing, which is further connected to adjacent dimer to form a tetramer via corner sharing, and such a tetramer is then interlinked into a 2D layer through bts3- ligands; the adjacent 2D layers are finally constructed to a 3D structure by sharing the L2 4- ligand. Compound 2 can be applied as an excellent luminescent sensor for sensing of VO3 - anion. Furthermore, the probable fluorescent quenching mechanisms of the two compounds have also been studied.

8.
ACS Omega ; 3(12): 16735-16742, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31458303

RESUMO

A stable 2D terbium oxalatophosphonate with green luminescence, namely, [Tb2(H3L)(C2O4)3(H2O)4]·2H2O (1), has been hydrothermally obtained by using (4-carboxypiperidyl)-N-methylenephosphonic acid (H3L) and oxalate ligand. The luminescent investigation indicates that the emission behavior of compound 1 shows high water and pH stabilities. It can be applied as a multiresponsive luminescent probe with high selectivity, high sensitivity, recycling capability, and fast sensing of CrO4 2-, Cr2O7 2- anions and tryptophan (Trp) molecules in aqueous solution through the luminescence quenching effect. Moreover, the sensing results can be distinguished by the naked eye under the irradiation of UV light of 254 nm. In addition, the probable mechanisms for the quenching behavior are also discussed, which can be mainly attributed to the competitive absorption of excitation energy between compound 1 and the analytes.

9.
Dalton Trans ; 43(4): 1542-9, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24213567

RESUMO

By the introduction of oxalate as the second ligand, five new lanthanide oxalatophosphonate hybrids with a 2D layered structure, namely, [Ln(H2L)(C2O4)(H2O)]·2H2O [Ln = Nd (1), Sm (2), Eu (3), Tb (4), Dy (5), H3L = H2O3PCH2NCH2(CH2CH2OPO2H)], have been hydrothermally synthesized and structurally characterized by X-ray single-crystal diffraction, X-ray powder diffraction, infrared spectroscopy, elemental analysis and thermogravimetric analysis. Compounds 1-5 are isostructural and exhibit a 2D layer formed by the interconnection of a 1D zigzag chain of {Ln(C2O4)}(+) with the phosphonate ligands. The effect of lanthanide contraction induces the decrease of the lattice parameters and crystal size from Nd to Dy. The luminescence properties of compounds 2-5 have been studied.

10.
Dalton Trans ; 42(22): 8009-17, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-23563190

RESUMO

Two novel lead(II) carboxyphosphonates with a layered and a 3D framework structure, namely, [Pb2Cl3(H2L)]·H2O (1) and [Pb2(HL)(HBTC)] (2) (H3L = H2O3PCH2-NC5H9-COOH, H3BTC = 1,3,5-benzenetricarboxylic acid), have been synthesized under hydrothermal conditions and structurally characterized. For compound 1, the interconnection of Pb(1)O2Cl3, Pb(2)O2Cl3, and CPO3 polyhedra via corner- and edge-sharing forms a 1D chain. The adjacent chains connect with each other by sharing the chloride anion, thereby generating a 2D layered structure in the ab-plane. The lattice water molecules are located between adjacent layers. Compound 2 exhibits a 3D pillared-layered structure. The Pb(1)O5, Pb(2)O5, and CPO3 polyhedra are interconnected into a 1D double chain via corner- and edge-sharing, which is further linked to adjacent chains through carboxyphosphonate ligands to form a 2D double layer structure. Neighboring double layers are bridged through the second linkers HBTC(2-), leading to a 3D pillared-layered structure with a 1D channel system along the a-axis. An interesting feature of compound 1 is the presence of the dehydration/hydration properties. It is worth noting that compound 2 can be stable up to a high temperature. The luminescent properties of compounds 1 and 2 have also been studied.

11.
Dalton Trans ; 41(36): 10948-56, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22580847

RESUMO

By introduction of 1,4-benzenedicarboxylic acid as the second organic ligand, a series of novel lanthanide carboxyphosphonates with a 3D framework structure, namely, [Ln(3)(H(2)L)(HL)(2)(bdc)(2)(H(2)O)]·7H(2)O (Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8); H(3)L = H(2)O(3)PCH(2)NC(5)H(9)COOH; H(2)bdc = HOOCC(6)H(4)COOH) have been synthesized under hydrothermal conditions. Compounds are isostructural and feature a 3D framework in which Ln(III) polyhedra are interconnected by bridging {CPO(3)} tetrahedra into 2D inorganic layers parallel to the ab plane. The organic groups of H(2)L(-) are grafted on the two sides of the layer. These layers are further cross-linked by the bdc(2-) ligands from one layer to the Ln atoms from the other into a pillared-layered architecture with one-dimensional channel system along the a axis. The thermal stability of compounds has been investigated. Luminescent properties of compounds , and the magnetic properties of compound have also been studied.

12.
Dalton Trans ; 40(18): 5059-65, 2011 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-21451880

RESUMO

By introduction of 1,4-benzenedicarboxylic acid as a second organic ligand, two new divalent metal(II) phosphonates with a 3D framework structure, namely, [Zn(HL1)(bdc)(0.5)] (1) and [Cd(1.5)(HL2)(bdc)(0.5)] (2) (H(2)L1 = H(2)O(3)PCH(NH(2))C(6)H(5), H(3)L2 = H(2)O(3)PCH(2)-NC(5)H(9)-COOH, H(2)bdc = HOOCC(6)H(4)COOH), have been synthesized under hydrothermal conditions. The two compounds show three-dimensional (3D) framework structure with infinite two-dimensional (2D) networks pillared by H(2)bdc. For compound 1, the {ZnO(4)} polyhedra are interconnected by phosphonate groups into a 2D layer, and the adjacent layers are further cross-linked via the bdc(2-) anions to generate a three-dimensional framework structure with two types of channel system along the c-axis. A notable feature of compound 1 is the presence of alternate left- and right-handed helical chains in the structure. In compound 2, the inorganic chains, composed of {Cd(1)O(7)}, {Cd(2)O(4)} and {CPO(3)} polyhedra, are linked by HL2(2-) ligands to form a double layer structure in the ab plane, and the adjacent layers are further linked by the bdc(2-) anions to form a 3D framework structure with one-dimensional channel systems along the a-axis. Luminescence properties of compounds 1 and 2 have also been studied.

13.
Dalton Trans ; 40(20): 5584-90, 2011 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-21503365

RESUMO

Eleven new lanthanide oxalatophosphonate hybrids with a 2D layered structures, namely, [Ln(H(3)L)(C(2)O(4))]·2H(2)O (Ln = La-Dy, Er and Y, H(4)L = C(6)H(5)CH(2)N(CH(2)PO(3)H(2))(2)), have been synthesized under hydrothermal conditions and structurally characterized by X-ray single-crystal diffraction, X-ray powder diffraction, infrared spectroscopy, elemental analysis and thermogravimetric analysis. Compounds 1-11 are isomorphous and they exhibit a 2D framework structure. Two {LnO(8)} polyhedra and four {CPO(3)} tetrahedra are interconnected into a unit via corner-sharing, and the so-built units are bridged by the oxalate anions into a layer. The result of connections in this manner is the formation of a 24-atom window. The thermal stabilities and guest desorption-sorption properties of compounds 1-11 have been investigated. The luminescent properties of compounds 5, 6, 8 and 9 have also been studied.

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