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1.
Eur Arch Psychiatry Clin Neurosci ; 274(5): 1167-1175, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38265467

RESUMO

This study aims to explore the link between Apo-E, brain white matter, and suicide in patients with major depressive disorder (MDD) to investigate the potential neuroimmune mechanisms of Apo-E that may lead to suicide. Thirty-nine patients with MDD (22 patients with suicidality) and 57 age, gender, and education-matched healthy controls participated in this study, provided plasma Apo-E samples, and underwent diffusion tensor imaging scans. Plasma Apo-E levels and white matter microstructure were analyzed among the MDD with suicidality, MDD without suicidality, and HC groups using analysis of variance with post hoc Bonferroni correction and tract-based spatial statistics (TBSS) with threshold-free cluster enhancement correction. Mediation analysis investigated the relationship between Apo-E, brain white matter, and suicidality in MDD. The MDD with suicidality subgroup had higher depressive and suicide scores, longer disease course, and lower plasma Apo-E levels than MDD without suicidality. TBSS revealed that the MDD non-suicide subgroup showed significantly increased mean diffusivity in the left corticospinal tract and body of the left corpus callosum, as well as increased axial diffusivity in the left anterior corona radiata and the right posterior thalamic radiation compared to the suicidal MDD group. The main finding was that the increased MD of the left corticospinal tract contributed to the elevated suicide score, with Apo-E mediating the effect. Preliminary result that Apo-E's mediating role between the left corticospinal tract and the suicide factor suggests the neuroimmune mechanism of suicide in MDD. The study was registered on ClinicalTrials.gov (NCT03790085).


Assuntos
Apolipoproteínas E , Transtorno Depressivo Maior , Imagem de Tensor de Difusão , Tratos Piramidais , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apolipoproteínas E/genética , Apolipoproteínas E/sangue , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/patologia , Transtorno Depressivo Maior/fisiopatologia , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/patologia , Tratos Piramidais/fisiopatologia , Ideação Suicida , Suicídio , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Estudos de Casos e Controles
2.
Inorg Chem ; 62(4): 1591-1601, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36657028

RESUMO

In this work, CAU-10-H@γ-AlOOH is prepared, and then UTSA-16 is loaded on CAU-10-H@γ-AlOOH to obtain UTSA-16@CAU-10-H@γ-AlOOH. Using the as-prepared composites as stationary materials by cryogenic gas chromatography at 77 K, while CAU-10-H@γ-AlOOH achieves the complete separation of ortho-H2 (o-H2) and D2 with a resolution R of 1.66 and a separation time t of 9.52 min, UTSA-16@CAU-10-H@γ-AlOOH achieves higher efficiency separation of hydrogen isotopes in a shorter separation time (4.56 min) with R = 1.7. Molecular simulation results show that CAU-10-H has both chemical affinity quantum sieving and kinetic sieving effects for H2/D2 at 77 K, and UTSA-16 can only exert the kinetic sieving effect. UTSA-16's load on CAU-10-H@γ-AlOOH weakens the adsorption of hydrogen isotopes, and the presence of Co2+ in UTSA-16 promotes the conversion of para-H2 to ortho-H2. In gas chromatography, H2 was preferentially desorbed from the system due to strong D2 adsorption caused by the chemical affinity quantum sieving effect and faster H2 diffusion caused by the kinetic sieving effect. These additive effects achieved efficient hydrogen isotope separation at 77 K.

3.
Rheumatology (Oxford) ; 61(7): 2923-2930, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34791076

RESUMO

OBJECTIVE: The aim of this observational cohort study was to assess the effectiveness and safety of the IL-6-receptor inhibitor tocilizumab (TCZ) in Behçet's syndrome (BS) with refractory arterial involvement. METHODS: Ten patients admitted to the Rheumatology and Immunology Department of Peking University People's Hospital between January 2014 and December 2019 were enrolled. The enrolled patients met the BS international criteria and exhibited severe arterial impairments. Refractory arterio-BS was diagnosed based on objective vascular symptoms unexplainable by other known illnesses, and resistance to traditional immunosuppressants and glucocorticoids after 12 weeks. Patients received 8 mg/kg TCZ infusions every 4 weeks for ≥24 weeks, with simultaneous continuation of immunosuppressants and glucocorticoids. Clinical and imaging data were assessed before and after TCZ treatment. RESULTS: The enrolled patients were men aged 44.3 (10.5) years; the median disease duration was 186.5 (45.7) months, and the average age of arterial impairment onset was 38.7 (12.9) years. The following trends were observed: improvement and maintenance of symptoms after the 26.8 (7.2)-month follow-up, n = 9; complete remission, n = 6; partial response, n = 3; immunosuppressant dose reduction, n = 4; radiologic improvement of arterial lesions, n = 4; and TCZ discontinuation owing to enlarged abdominal aortic aneurysm relapse, n = 1. The average daily glucocorticoid dose reduced from 54.5 (20.6) to 8.3 (3.6) mg/d (P < 0.001), while the median ESR and CRP values reduced from 50 (2-82) mm/h and 32.9 (2.1-62.3) mg/dl to 4 (1-10) mm/h and 2.9 (0.2-12.1) mg/dl, respectively (P < 0.001). No TCZ-associated side effects were noted. CONCLUSION: TCZ proved to be safe and effective for refractory arterial lesions in BS, with a steroid- and immunosuppressant-sparing benefit.


Assuntos
Síndrome de Behçet , Adulto , Anticorpos Monoclonais Humanizados , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/tratamento farmacológico , China , Estudos de Coortes , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/efeitos adversos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
4.
Inorg Chem ; 61(3): 1512-1520, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34969248

RESUMO

Maintaining a long-term continuous and stable reactivator blood concentration to treat organophosphorus nerve agent poisoning using acetylcholinesterase (AChE) reactivator pralidoxime chloride (2-PAM) is very important yet difficult. Because the flexible framework of MIL-88B(Fe) nanoparticles (NPs) can swell in polar solvents, pralidoxime chloride (2-PAM) was loaded in MIL-88B(Fe) NPs (size: ca. 500 nm) by stirring and incubation in deionized water to obtain 2-PAM@MIL-88B(Fe), which had a maximum drug loading capacity of 12.6 wt %. The as-prepared composite was characterized by IR, powder X-ray diffraction (P-XRD), scanning electron microscopy (SEM), ζ-potential, Brunauer-Emmett-Teller (BET), and thermogravimetry/differential thermal analysis (TG/DTA). The results showed that under constant conditions, the maximum drug release rates of 2-PAM@MIL-88B(Fe) in absolute ethanol, phosphate-buffered saline (PBS) solution (pH = 7.4), and PBS solution (pH = 4) at 150 h were 51.7, 80.6, and 67.1%, respectively. This was because the composite showed different swelling behaviors in different solvents. In PBS solution with pH = 2, the 2-PAM@MIL-88B(Fe) framework collapsed after 53 h and released 100% of 2-PAM. For mice after intragastric poisoning with sarin (a neurotoxic agent), an atropine-assisted 2-PAM@MIL-88B(Fe) treatment experiment revealed that 2-PAM@MIL-88B(Fe) continuously released 2-PAM for more than 72 h so that poisoned AChE was continuously and steadily reactivated. The reactivation rate of AChE was 56.7% after 72 h. This composite is expected to provide a prolonged, stable therapeutic drug for the mid- and late-stage treatment of neurotoxic agent poisoning.


Assuntos
Estruturas Metalorgânicas/química , Agentes Neurotóxicos/farmacologia , Compostos de Pralidoxima/farmacologia , Sarina/antagonistas & inibidores , Acetilcolinesterase/análise , Acetilcolinesterase/metabolismo , Administração Oral , Animais , Atropina/administração & dosagem , Atropina/farmacologia , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos , Nanopartículas/química , Agentes Neurotóxicos/química , Compostos de Pralidoxima/administração & dosagem , Compostos de Pralidoxima/química , Sarina/administração & dosagem , Sarina/toxicidade
5.
Ann Rheum Dis ; 79(1): 141-149, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31537547

RESUMO

OBJECTIVES: Open-labelled clinical trials suggested that low-dose IL-2 might be effective in treatment of systemic lupus erythematosus (SLE). A double-blind and placebo-controlled trial is required to formally evaluate the safety and efficacy of low-dose IL-2 therapy. METHODS: A randomised, double-blind and placebo-controlled clinical trial was designed to treat 60 patients with active SLE. These patients received either IL-2 (n=30) or placebo (n=30) with standard treatment for 12 weeks, and were followed up for additional 12 weeks. IL-2 at a dose of 1 million IU or placebo was administered subcutaneously every other day for 2 weeks and followed by a 2-week break as one treatment cycle. The primary endpoint was the SLE Responder Index-4 (SRI-4) at week 12. The secondary endpoints were other clinical responses, safety and dynamics of immune cell subsets. RESULTS: At week 12, the SRI-4 response rates were 55.17% and 30.00% for IL-2 and placebo, respectively (p=0.052). At week 24, the SRI-4 response rate of IL-2 group was 65.52%, compared with 36.67% of the placebo group (p=0.027). The primary endpoint was not met at week 12. Low-dose IL-2 treatment resulted in 53.85% (7/13) complete remission in patients with lupus nephritis, compared with 16.67% (2/12) in the placebo group (p=0.036). No serious infection was observed in the IL-2 group, but two in placebo group. Besides expansion of regulatory T cells, low-dose IL-2 may also sustain cellular immunity with enhanced natural killer cells. CONCLUSIONS: Low-dose IL-2 might be effective and tolerated in treatment of SLE. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registries (NCT02465580 and NCT02932137).


Assuntos
Antirreumáticos/uso terapêutico , Interleucina-2/administração & dosagem , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Nefrite Lúpica/tratamento farmacológico , Adulto , Método Duplo-Cego , Feminino , Humanos , Interleucina-2/uso terapêutico , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Resultado do Tratamento , Adulto Jovem
6.
Inorg Chem ; 59(16): 11595-11605, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32799468

RESUMO

Due to the unpredictable nature of a battlefield environment, in the simultaneous degradation of sulfur mustard and nerve agents it is preferable to use just one decontaminant. Herein, the new composite HPVMo@MOF-808 (HPVMo = H5PV2Mo10O40) was deliberately synthesized via a simple impregnation method and thoroughly characterized. The results showed that the decontamination rate of the composites (30-40 mg) with optimal HPVMo loadings for HD (4 µL) and GD (4 µL) under ambient conditions was 97.2% (within 120 min) and 90.8% (within 30 min), respectively. Due to the combinational/synergistic effect of MOF-808 and encapsulated homogeneously dispersed HPVMo, the composite can very efficiently oxidize HD to nontoxic products in a single system, while retaining the inherent excellence of MOF-808 in hydrolytically degrading GD. The decontamination process was found to follow first-order reaction kinetics, and the rate constant and half-life of the composite for HD and GD were 0.0231 min-1, 30.13 min and 0.0795 min-1, 8.72 min, respectively. In addition, experimental results in guinea pigs and Kunming mice used as animal models showed that the composite provided effective skin protection against HD and GD, showing great potential for application in skin decontamination and protection.


Assuntos
Substâncias para a Guerra Química/química , Estruturas Metalorgânicas/química , Gás de Mostarda/química , Soman/química , Compostos de Tungstênio/química , Animais , Substâncias para a Guerra Química/intoxicação , Cobaias , Camundongos , Intoxicação/prevenção & controle
7.
Ann Nutr Metab ; 76(1): 54-61, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32182619

RESUMO

INTRODUCTION: The role of tea consumption on rheumatoid arthritis (RA) has been studied in recent years, but no clear conclusion has been drawn as a result of small sample size of the studies or the fact that only in vitro studies have been performed. OBJECTIVES: The aim of this study was to explore the possible association of tea consumption with RA through a large-scale, real-world study. METHODS: A total of 733 RA patients were investigated from June to December, 2016. The disease activity of RA was assessed according to disease activity score 28-erythrocyte sedimentation rate. The amount and types of tea consumption were recorded by on-site self-administered questionnaires. Logistic regression models were applied to analyze the correlation between tea consumption and disease activity, adjusting for demographics, clinical and laboratory factors. RESULTS: There was an inverse association between tea consumption and disease activity in RA patients (OR 0.66, 95% CI 0.46-0.94). Compared with non-tea drinkers, a higher-intake of tea (>750 mL/day) was associated with lower disease activity of RA (OR 0.39, 95% CI 0.19-0.79), but not low-intake (≤750 mL/day; OR 0.83, 95% CI 0.42-1.63). A significant dose-response association was found between the amount of tea consumption and disease activity (p for trend <0.01). Further hierarchical regression analysis showed that such inverse associations were mainly present in female patients (p = 0.004), non-smokers (p = 0.01) or elders (≥60 years; p = 0.01). CONCLUSION: Tea consumption is associated with decreased disease activity of RA, suggesting the potential beneficial effect of tea in the disease.


Assuntos
Artrite Reumatoide , Chá , Idoso , Feminino , Humanos , Modelos Logísticos , Fatores de Risco , Inquéritos e Questionários
8.
Inorg Chem ; 58(13): 8763-8774, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247847

RESUMO

Four new organic-inorganic hybrids, [N(C4H9)4]5H[{HNC2O(CH2O)3P2V3W15O59}C44N4H29O3] (TPPOH-1POM), [N(C4H9)4]10H2[{HNC2O(CH2O)3P2V3W15O59}2C44N4H28O2] (TPPOH-2POM trans), [N(C4H9)4]10H2[{HNC2O(CH2O)3P2V3W15O59}2C44N4H28O2] (TPPOH-2POM cis), and [N(C4H9)4]15H3[{HNC2O(CH2O)3P2W15V3O59}3C44N4H27O] (TPPOH-3POM), have been synthesized by covalently grafting the Dawson-type polyoxometalate (POM) [N(C4H9)4]5[H4P2W15V3O62] onto new porphyrins N-[1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl]-4-[10,15,20-tris(4-hydroxyphenyl)porphyrin-5-yl]benzamide (TPPOH-1Tris), 4,4'-[5,15-bis(4-hydroxyphenyl)porphyrin-10,20-diyl]bis[ N-[1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl]benzamide] (TPPOH-2Tris trans), 4,4'-[10,15-bis(4-hydroxyphenyl)porphyrin-5,20-diyl]bis[ N-[1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl]benzamide] (TPPOH-2Tris cis). and 4,4',4″-[20-(4-hydroxyphenyl)porphyrin-5,10,15-triyl]tris[ N-[1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl]benzamide] (TPPOH-3Tris), respectively, in N, N-dimethylacetamide under nitrogen. The hybrid compounds were thoroughly characterized by elemental analysis, FT-IR, NMR (1H, 2D NOESY, 31P, and 51V), ESI-MS, MALDI-TOF-MS, UV-vis, and fluorescence spectroscopy. All porphyrins and their corresponding hybrids exhibited remarkable third-order nonlinear-optical responses under laser irradiation, with the intensity of light at focus E0 being 4.2 µJ at wavelength 532 nm, pulse duration τ = 6 ns, and repetition rate 10 Hz. The molecular second hyperpolarizability (γ) values of the hybrids (TPPOH-1POM, TPPOH-2POM trans, TPPOH-2POM cis, TPPOH-3POM) were calculated to be 8.48 × 10-28 esu, 8.94 × 10-28 esu, 10.16 × 10-28 esu, and 8.93 × 10-28 esu, while the molecular second hyperpolarizability (γ) of their corresponding porphyrin precursors (TPPOH-1Tris, TPPOH-2Tris trans, TPPOH-2Tris cis, and TPPOH-3Tris) were 7.19 × 10-28 esu, 8.09 × 10-28 esu, 9.07 × 10-28 esu, and 7.24 × 10-28 esu, respectively. The γ values of the cis forms were found to be superior to those of all other compounds, indicating the significant role of the greater dipole moment and low symmetry of the cis form compared to other compounds. It was also found that the fluorescence intensity was decreased by 81.52%, 90.37%, 93.93%, and 84.62% for the hybrids TPPOH-1POM, TPPOH-2POM trans, TPPOH-2POM cis, and TPPOH-3POM with respect to their corresponding precursors, respectively, which reveals the Dawson-type POM as a strong quencher. This quenching phenomenon not only indicates again unequivocally the formation of hybrid compounds but also may imply a photoinduced electron/energy-transfer process favored from a porphyrin moiety to a Dawson-type POM moiety.

9.
Inorg Chem ; 57(3): 995-1003, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29319311

RESUMO

Three new isostructural chiral silver-lanthanide heterometal-organic frameworks [Ag3Ln7(µ3-OH)8(bpdc)6(NO3)3(H2O)6](NO3)·2H2O [Ln = Eu (1), Tb (2, Sm (3); H2bpdc = 2,2'-bipyridine-3,3'-dicarboxylic acid] based on heptanuclear lanthanide clusters [Ln7(µ3-OH)8]13+ comprised of one-dimensional triple right-handed helical chains were hydrothermally synthesized. Various means such as UV-vis spectroscopy, IR spectroscopy, elemental analysis, powder X-ray diffraction, and thermogravimetric/differential thermal analysis were used to characterize the compounds, wherein compound 3 was crystallographically characterized. In the structure of compound 3, eight µ3-OH- groups link seven Sm3+ ions, forming a heptanuclear cluster, [Sm7(µ3-OH)8]13+, and the adjacent [Sm7(µ3-OH)8]13+ clusters are linked by the carboxylic groups of bpdc2- ligands, leading to the formation of a one-dimensional triple right-handed helical chain. The adjacent triple right-handed helical chains are further joined together by coordinating the pyridyl N atoms of the bpdc2- ligands with Ag+, resulting in a chiral three-dimensional silver(I)-lanthanide(III) heterometal-organic framework with one-dimensional channels wherein NO3- anions and crystal lattice H2O molecules are trapped. The compounds were studied systematically with respect to their photoluminescence properties and energy-transfer mechanism, and it was found that H2bpdc (the energy level for the triplet states of the ligand H2bpdc is 21505 cm-1) can sensitize Eu3+ luminescence more effectively than Tb3+ and Sm3+ luminescence because of effective energy transfer from bpdc2- to Eu3+ under excitation in compound 1.

10.
Inorg Chem ; 56(1): 156-166, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-27936639

RESUMO

A series of isostructural compounds Na(HL)(CH3COO)Ln(Al(OH)6Mo6O18)(H2O)6·10H2O [L = nicotinate; Ln = Eu (1), Tb (2)] and Na(HL)(CH3COO)EumTbnLa1-m-n(AlMo6(OH)6O18)(H2O)6·10H2O (3-8, L = nicotinate), wherein Anderson-type polyanions AlMo6(OH)6O183- as basic inorganic building blocks are connected by Eu(CH3COO)(HL)(H2O)3]24+ and [Na2(H2O)8]2+ cations, resulting in formation of three-dimensional lanthanide metal-organic open frameworks, were synthesized successfully with AlCl3·6H2O, Na2MoO4·2H2O, nicotinic acid, and lanthanide nitrates as starting materials. The compounds were characterized by UV-vis, IR, elemental analysis, powder XRD, and TG-DTA measurements. The single-crystal structures of compounds 1 and 2 show that the two compounds display three-dimensional open frameworks with 1D channels along the b and c axes. Investigation of the energy transfer mechanism indicated that the organic nicotinate ligand can transfer energy efficiently to Tb3+ rather than Eu3+. The influence of the POM moiety on the fluorescence of the compounds is also studied. Compounds 1-8 exhibit tunable luminescence color, and emitting of white light was realized through adjusting the molar ratio of Eu:Tb:La within the compounds.

11.
Inorg Chem ; 56(16): 9436-9447, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28795802

RESUMO

Two new porphyrin-polyoxometalate hybrids, namely, [(C4H9)4N]10H2[{COHNC(CH2O)3P2V3W15O59}2C44N4H28]·CH3CN 1, bearing two covalent-bonded Wells-Dawson-type polyoxometalates (POMs), and [(C4H9)4N)]5H[COHNC(CH2O)3P2V3W15O59{C44H29N4}]·CH3CN 2, bearing one covalent-bonded POM, have been synthesized and thoroughly characterized by means of elemental analysis, powder XRD, FT-IR, 1H (31P, 51V) NMR, MALDI-TOF-MS, UV-vis spectra, and cyclic voltammetry measurement. Experimental results demonstrate that while all the compounds show remarkable third-order optical nonlinearities, the hybrids 1 and 2 are superior to their corresponding porphyrin precursors (molecular second hyperpolarizability γ = 8.0 × 10-28 esu for 54-N-N'(1,3-tetrahydroxy-2-(dihydroxymethyl)propan-4-diyl)benz-diamide,10,15,20-triphenyl porphyrin that is the precursor for the hybrid 1, γ = 2.6 × 10-28 esu for 54-N-(1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl)benz-amide,10,15,20-triphenyl porphyrin that is the precursor for the hybrid 2), and the hybrid 1 (γ = 12.9 × 10-28 esu) is superior to the hybrid 2 (γ = 12.2 × 10-28 esu) reflecting more POM moieties covalently bonded to the porphyrin moiety exerting more significant influence on the third-order optical nonlinearities. Meanwhile, attachment of POMs on the porphyrin results in significant fluorescence quenching (fluorescence intensity is decreased 97% for the hybrid 1 and 80% for the hybrid 2 with respect to that of their corresponding porphyrin precursors) indicating strong electron transfer from porphyrin moiety to the polyoxometalate moiety. Lower transition energy, small energy difference between singlet and triplet excited states, and faster intersystem crossing (ISC) process of the hybrids are favorable to enhance the NLO responses of hybrids 1 and 2 resulting from the facile electron transfer from the porphyrin moiety to the Dawson POM moiety when the hybrids are subjected to laser irradiation, which is thought to be responsible to the superior of the hybrid 1 to hybrid 2 and the superior of the hybrids to their corresponding porphyrin precursors as well.

12.
Photochem Photobiol Sci ; 13(4): 660-70, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24525619

RESUMO

A new series of four isostructural mononuclear lanthanide complexes Ln(HPDH)3(H2O)3·H2O (Ln = Sm(III) 1, Eu(III) 2, Tb(III) 3 and Dy(III) 4; H2PDH = 6,7-dihydropyrido(2,3-d)pyridazine-5,8-dione) has been prepared and characterized by IR, elemental analysis, XRD and TG-DTA methods. Single crystal X-ray diffraction analysis of both complexes 1 and 3 revealed that the mononuclear discrete complexes form 3-D supramolecular networks via hydrogen bonds and offset stacking (­H···π) interactions. The photoluminescence study of the title complexes revealed the photoluminescent potential of the antenna ligand (H2PDH) toward the concerned lanthanide cations. The luminescence based sensing ability of the partially dehydrated complex Tb(HPDH)3(H2O)33a towards small solvent molecules, along with its reusability, has been studied. Isopropyl alcohol was found to be an excellent sensitizer, while tetrahydrofuran was a highly quenching solvent with a first order behavior towards the photoluminescence intensity. The photoluminescence intensity was found to decrease with the increase of the dielectric constant and normalized Dimroth­Reichardt ET parameter values for protic solvents, while reverse behavior was observed for dipolar aprotic solvents.

13.
Inorg Chem ; 53(7): 3362-70, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24635220

RESUMO

A new family of silver(I)-lanthanide(III) heterometallic-organic frameworks having the formula [AgLn(bpdc)2] (Ln = Eu (1), Tb (2), Sm (3), Dy (4), Y (5), Yb (6), Er (7), Ho (8); H2bpdc = 2,2'-bipyridine-3,3'-dicarboxylic acid), each of which crystallizes in the monoclinic space group C2/c with Z = 4, has been hydrothermally synthesized. The compounds were characterized by means of IR, elemental analysis, thermogravimetric-differential thermal analysis, and powder X-ray diffraction (XRD), wherein compounds 1, 2, and 4-8 were structurally characterized. The powder XRD and single-crystal structures of the title compounds indicate that all the compounds are isostructural and feature a three-dimensional (3-D) open framework. In the structures of the compounds, bpdc(2-) ligands link Ln(3+) through their carboxylic groups, resulting in the formation of a one-dimensional {Ln(bpdc)2}n infinite chain along the c direction. The adjacent chains are then connected to each other through the coordination interaction between Ag(+) and the pyridyl N atoms of bpdc(2-) ligands from the chains, resulting in a 3-D (2,4,6)-connected open framework with (4(11)·6(4))(4(3)·8(2)·10)(8)2 topology. The compounds show remarkable good thermally stability up to 370 °C because neither aquo ligands nor lattice water molecules exist in the composition of the compounds. The photoluminescent properties of compounds 1 and 2 were studied in detail. The energy level of the triplet states of the ligand H2bpdc 21,505 cm(-1) (465 nm) was determined based on the 77 K emission spectrum of the compound [Gd2(bpdc)3(phen)2(H2O)2]·6H2O 9. The (5)D0 and (5)D4 emission lifetimes (1.58 and 1.76 ms) and the overall quantum yields (21% and 22%) were determined for the compounds 1 and 2, respectively.

14.
Luminescence ; 29(5): 531-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24123974

RESUMO

A new sensitive quaternary photoluminescence enhancement system has been successfully developed to determine trace amounts of Eu(3+) and Zn(2+). The photoluminescence intensity of Eu - N-(o-vanilin)-1,8-diaminonaphthalene systems was greatly increased by the addition of specific concentrations of 1, 10-phenanthroline and Zn(2+). The excitation and emission wavelengths were 274 and 617 nm, respectively. Under optimal system conditions, the photoluminescence intensity showed a linear response toward Eu(3+) in the range of 5.0 × 10(-6) ~ 2.0 × 10(-5) M with a limit of detection (= 2.2 × 10(-9) M) and the photoluminescence intensity of the system decreased linearly by increasing the Zn(2+) concentration in the range of 5.0 × 10(-8) ~ 1.0 × 10(-6) M with a limit of detection (= 8.8 × 10(-11) M). This system was successfully applied for the determination of trace amounts of Eu(3+) in a high purity La2O3 matrix and in the synthetic rare earth oxide mixture, and of Zn(2+) in a high purity Mg(NO3)2 · 6H2O matrix and in synthetic coexisting ionic matrixes. The energy transfer mechanism, photoluminescence enhancement of the system and interference of other lanthanide ions and common coexisting ions were also studied in detail.


Assuntos
Európio/análise , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Zinco/análise , 2-Naftilamina/análogos & derivados , 2-Naftilamina/química , Benzaldeídos/química , Substâncias Luminescentes/síntese química , Fenantrolinas/química
15.
Sci Technol Adv Mater ; 15(3): 035010, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27877686

RESUMO

Tumor growth depends on angiogenesis, which can furnish the oxygen and nutrients that proliferate tumor cells. Thus, blocking angiogenesis can be an effective strategy to inhibit tumor growth. In this work, three typical nanoparticles based on polyoxometalates (POMs) have been prepared; we investigated their capability as antitumor and anti-angiogenesis agents. We found that Mo POM nanoparticles, especially complex 3, inhibited the growth of human hepatocellular liver carcinoma cells (HepG2) through cellular reactive oxygen species levels' elevation and mitochondrial membrane potential damage. Complex 3 also suppressed the proliferation, migration, and tube formation of endothelial cells in vitro and chicken chorioallantoic membrane development ex vivo. Furthermore, western blot analysis of cell signaling molecules indicated that Mo POMs blocked the vascular endothelial growth factor receptor 2-mediated ERK1/2 and AKT signaling pathways in endothelial cells. Using transmission electron microscopy, we demonstrated their cellular uptake and localization within the cytoplasm of HepG2 cells. These results indicate that, owing to the extraordinary physical and chemical properties, Mo POM nanoparticles can significantly inhibit tumor growth and angiogenesis, which makes them potential drug candidates in anticancer and anti-angiogenesis therapies.

16.
Anal Methods ; 16(25): 4066-4073, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38881395

RESUMO

Nerve agents have posed a huge threat to national and human security, and their sensitive detection is crucial. Herein, based on the oxidation of Ce4+ and the aggregation-induced emission (AIE) of glutathione-protected gold nanoclusters (GSH-Au NCs), a cascade reaction was designed to prepare oxidized 3,3',5,5'-tetramethylbenzidine (oxTMB) and GSH-Au NCs crosslinked by Ce3+ (Ce3+-GSH-Au NCs). oxTMB had a broad UV-visible absorption range (500-700 nm) and was capable of quenching the fluorescence of Ce3+-GSH-Au NCs at 590 nm through the internal filtration effect (IFE). Thiocholine (TCh), the hydrolysis product of acetylthiocholine chloride (ATCl) catalyzed by acetylcholinesterase (AChE), reduced oxTMB completely, resulting in a decrease in the absorption of oxTMB and the recovery of IFE-quenched fluorescence of Ce3+-GSH-Au NCs. Nerve agent sarin (GB) hindered the production of TCh and the reduction of oxTMB by inhibiting the AChE activity, leading to the fluorescence of Ce3+-GSH-Au NCs being quenched again. The dual-output sensing system (AChE + ATCl + oxTMB + Ce3+-GSH-Au NCs) exhibited a low limit of detection to GB (2.46 nM for colorimetry and 1.18 nM for fluorimetry) and excellent selectivity toward common interferences being unable to inhibit AChE. Moreover, the intelligent logic gate constructed based on the sensing system showed promising applications in the field of smart sensing of nerve agents.


Assuntos
Acetilcolinesterase , Ouro , Nanopartículas Metálicas , Agentes Neurotóxicos , Sarina , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Sarina/química , Sarina/análise , Agentes Neurotóxicos/química , Agentes Neurotóxicos/análise , Ouro/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Cério/química , Glutationa/química , Humanos , Benzidinas/química , Espectrometria de Fluorescência/métodos , Limite de Detecção
17.
Clin Rheumatol ; 43(5): 1541-1550, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565803

RESUMO

OBJECTIVE: Systemic lupus erythematosus (SLE) is associated with a significant risk of atherosclerotic cardiovascular disease, especially in the development of premature atherosclerosis. Specific prediction models for premature atherosclerosis in SLE patients are still limited. The objective of this study was to establish a predictive model for premature atherosclerosis in SLE. METHOD: The study collected clinical and laboratory data from 148 SLE patients under the age of 55, between January 2021 and June 2023. The least absolute shrinkage and selection operator logistic regression model was utilized to identify potentially relevant features. Subsequently, a nomogram was developed using multivariable logistic analysis. The performance of the nomogram was evaluated through a receiver-operating characteristic curve, calibration curve, and decision curve analysis (DCA). RESULTS: A total of 148 SLE patients who fulfilled the inclusion criteria were enrolled in the study, of whom 53 patients (35.81%) met the definition of premature atherosclerosis. Hypertension, antiphospholipid syndrome, azathioprine use, duration of glucocorticoid, and age of patients were included in the multivariable regression. The nomogram, based on the non-overfitting multivariable model, was internally validated and demonstrated sufficient clinical utility for assessing the risk of premature atherosclerosis (area under curve: 0.867). CONCLUSIONS: The comprehensive nomogram constructed in this study serves as a useful and convenient tool for evaluating the risk of premature atherosclerosis in SLE patients. It is helpful for clinicians to early identify SLE patients with premature atherosclerosis and facilitates the implementation of more effective preventive measures. Key Points • SLE patients are at a significantly higher risk of developing premature atherosclerosis compared to the general population, and this risk persists even in cases with low disease activity. Traditional models used to evaluate and predict premature atherosclerosis in SLE patients often underestimate the risk. • This study establishes a comprehensive and visually orientated predictive model of premature atherosclerosis in SLE patients, based on clinical characteristics. • The scoring system allows for convenient and effective prediction of individual incidence of premature atherosclerosis, and could provide valuable information for identification and making further intervention decision.


Assuntos
Síndrome Antifosfolipídica , Aterosclerose , Hipertensão , Lúpus Eritematoso Sistêmico , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/epidemiologia , Aterosclerose/etiologia , Síndrome Antifosfolipídica/complicações , Hipertensão/complicações , Incidência , Fatores de Risco
18.
J Colloid Interface Sci ; 674: 791-804, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38955010

RESUMO

Selective oxidation of sulfur mustard gas (HD) to non-toxic sulfoxide by the visible-light-catalyzed generation of singlet oxygen (1O2) is a promising degradation strategy. Although PCN-224 can absorb visible light, it suffers from rapid electron-hole recombination and low redox capacity, which limits the performance of HD degradation. Titanium dioxide (TiO2) is an excellent photocatalyst but it lacks visible-light-activity in degrading HD. In this study, PCN-224@TiO2 heterojunction with S-type core-shell structure was synthesized by in-situ growth method to prolong the visible light absorption capacity of TiO2 and inhibit the rapid recombination of PCN-224. The interface formation and internal electric field were optimized by adjusting the Zr/Ti ratio to enhance the charge transfer, redox capacity, electron-hole separation, and visible light absorption. In this study, the formation of heterojunction composites based on Zr-O-Ti linkages is demonstrated by a series of characterization methods. It is demonstrated by experiments and theoretical calculations that PCN-224@TiO2 can generate nearly 100 % 1O2 under visible light conditions without a sacrificial agent, resulting in efficient and selective oxidation of 2-chloroethyl ethyl sulfide (CEES), a simulant of HD, to non-toxic sulfoxide form.

19.
Inorg Chem ; 52(11): 6338-45, 2013 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-23688305

RESUMO

Hydrothermal reactions of lanthanide nitrates with glyphosate have resulted three new isostructural 3D lanthanide-organic frameworks, Ln(NO3)(H2L) [Ln = Eu (1), Tb (2), Gd (3); H4L = 2,5-dioxo-1,4-piperazinylbis(methylphosphonic) acid], with good yields, where H4L as a new ligand was formed via in situ cyclodehydration of original ligand glyphosates during the hydrothermal reaction. The compounds were thoroughly characterized by IR, UV-vis, elemental analysis, single-crystal X-ray diffraction analysis, powder X-ray diffraction analysis, and thermogravimetric/differential thermal analysis (TG-DTA). Three compounds display 3D 6,6-connected open frameworks with 4(13)·6(2) topology possessing 1D channels in which NO3(-) anions act as troglodytes by chelating Ln(3+) centers. The TG-DTA study of the compounds showed remarkable thermal stability up to 380 °C. Under room temperature UV-light irradiation, the Eu(3+) and Tb(3+) compounds showed the corresponding characteristic Ln(3+) intra 4f(n) emission peaks. The triplet energy level (21882 cm(-1)) of the ligand (H4L) was determined from the emission spectrum of its Gd(3+) compound at 77 K. The emission lifetimes (1.54 ms of (5)D0 for compound 1 and 1.98 ms of (5)D4 for compound 2) and absolute emission quantum yields (10.1% for compound 1 and 5.9% for compound 2) were also determined.


Assuntos
Glicina/análogos & derivados , Elementos da Série dos Lantanídeos/química , Luminescência , Compostos Organometálicos/química , Piperazinas/química , Cristalografia por Raios X , Glicina/química , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Processos Fotoquímicos , Glifosato
20.
Dalton Trans ; 52(2): 376-383, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36515365

RESUMO

The reaction of porous γ-Al2O3 particles acting as both a sacrificial template and an aluminum source with 1,4-naphthalene diacid (H2NDC) resulted in the formation of γ-AlOOH@Al(OH)(1,4-NDC) composites, in which ZIF-67 was then loaded by the in situ crystallization method, leading to the formation of γ-AlOOH@Al(OH)(1,4-NDC)@ZIF-67 composites. The deliberately designed composite was used to separate H2/D2 at 77 K in a 1 m chromatographic column. The results demonstrated that the optimized composite can achieve the effective separation of H2/D2 in gas chromatography due to the additive effects of kinetic sieving and chemical affinity quantum sieving of Al(OH)(1,4-NDC) and ZIF-67. By optimizing chromatographic separation conditions, the resolution R reached 2.02 with the separation time t = 7.72 min. The composite also showed satisfactory repeatability and reproducibility.

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