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1.
Inorg Chem ; 62(23): 8784-8788, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37253277

RESUMO

Herein we report the structural change and radical generation of a cadmium-based metal-organic framework (Cd-MOF) induced by external electric fields. Under a weaker single electric field, different coordination modes of Cd-L lead to 3D → 2D structural change. Under stronger superposed electric fields, Cd-MOF was excited to produce a stable free radical. This study will provide a new avenue for the controlled assembly of MOFs.

2.
Inorg Chem ; 61(3): 1521-1529, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34985269

RESUMO

The rational design and preparation of monolayer metal-organic framework (MOF) nanosheets remain great challenges. Recently, we found that monolayer MOF nanosheets can be facially exfoliated on a large scale from pristine two-dimensional (2D) MOFs with substantially reduced interlaminar interaction. By employing cage-like bicyclocalix[2]arene[2]triazine tri-imidazole as the building block, a family of cationic two-dimensional metal-organic frameworks (2D MOFs) with steric layer were designed and prepared. The single crystal structures have clearly identified that only very weak and sparse distributed C-H···π interaction exists between adjacent layers.On the basis of density functional theory calculation, the interlayer interaction of these cage-based cationic 2D MOFs was estimated to be 1/46th of that of graphite. Due to the extremely weak interaction, these cationic 2D MOFs tend to degenerate into an "amorphous" state after being soaked in other solvents; they can be readily exfoliated into 1.1 nm thick monolayer nanosheets with a high degree of thickness homogeneity, large lateral size, and significantly enlarged surface area. This work has identified that a cage-like molecule is the ideal building block for 2D cationic MOFs and ultrathin nanosheets; It was futher confirmed that weakening the interlaminar interaction is an effective strategy for facilely producing monolayer nanosheets.

3.
Curr Psychol ; : 1-11, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35068907

RESUMO

This study explored the chain mediating effects of rumination and anxiety in the relationship between online risky behavior and sleep quality among Chinese college students. A sample of 1039 Chinese college students (Mage = 19.49, SD = 1.14, 53.32% males) were investigated with Online Risky Behavior Scale (ORBS), Pittsburgh Sleep Quality Index scale (PSQI), Ruminative Responses Scale (RRS) and Self-rating Anxiety Scale (SAS). The results showed that: (1) There is a significant positive correlation among online risky behavior, sleep quality, rumination and anxiety, and (2) Online risky behavior could not directly affect sleep quality, but it can affect sleep quality through the mediation of rumination and anxiety. The chain mediating effects includes three paths: The mediating role of rumination, the mediating role of anxiety, and the chain mediating role of rumination and anxiety after controlling for gender, grade, major, and network usage time. These findings contribute to a deeper understanding of how online risky behavior affects sleep quality and provide important practical guidance for improving sleep quality.

4.
Endocr J ; 68(9): 1057-1065, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33907068

RESUMO

To examine the association between blood urea nitrogen (BUN) and risk of type 2 diabetes (T2DM) among Chinese adults, we performed an ongoing cohort study of 38578 Chinese adults (56.3% males; average age, 41.6 y) who underwent repeated health check-up examinations between 2009 and 2016 and without T2DM at baseline. During follow-up, incident T2DM cases were identified based on self-report, medication use, measurements of fasting plasma glucose, 2 h post oral glucose, or haemoglobinA1c. 2009 (5.2%) cases confirmed with incident T2DM were identified during median follow-up of 3.1 years. With increasing quartiles of BUN levels, the incidences of T2DM gradually increased with 0.69%, 1.11%, 1.53%, and 1.87% for quartile 1 to quartile 4 (p trend <0.001). Compared with quartile 1, the multivariate-adjusted hazard ratios (HRs) and its 95% confidence intervals (95% CIs) for T2DM risk were 1.16 (0.97-1.38) for quartile 2, 1.28 (1.07-1.51) for quartile 3, and 1.28 (1.08-1.52) for quartile 4 (p trend = 0.005). HR for per each standard deviation increase in BUN level was 1.10 (1.04-1.16) (p trend <0.001). This association tended to be more pronounced in those with a lower body mass index at baseline (p-interaction <0.001). Our results suggested that BUN levels were positively associated with incident T2DM risk among Chinese adults. Future prospective investigations in other populations are necessary to confirm our findings.


Assuntos
Nitrogênio da Ureia Sanguínea , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Adulto , Idoso , Povo Asiático/estatística & dados numéricos , Glicemia/análise , Índice de Massa Corporal , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
5.
Inorg Chem ; 59(20): 15019-15027, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33000937

RESUMO

Two novel fac-Re(CO)3-based rectangles {[(CO)3Re(µ-Cl)2Re(CO)3]2(µ-L)2} (1) and {[(CO)3Re(µ-OC4H9)2Re(CO)3]2(µ-L)2}(2) based on new photochromic dithienylethene-containing ligand 2,7-di(pyridin-4-yl)-9,10-bis(5-chloro-2-methylthien-3-yl)-phenanthrene (L) were prepared. They displayed varying photochromic properties both in solution and in the single-crystal state. Through a judicious choice of the bridging ligands along the short sides of the rectangles, the photophysical and electrochemical properties of the complexes could also be readily tuned.

6.
Appl Opt ; 59(25): 7646-7651, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32902465

RESUMO

We present the design of Ge1-xSnx-on-Si waveguide photodetectors for the applications in the C- to U-bands. The GeSn photodetectors have been studied in respect to responsivity, dark current, and bandwidth, with light butt- or evanescent-coupled from an Si waveguide. With the introduction of 4.5% Sn into Ge, the GeSn waveguide PD with evanescent-coupling exhibits high responsivity of 1.25 A/W and 3 dB bandwidth of 123.1 GHz at 1.675 µm. Further increasing the Sn composition cannot improve the absorption in the U-band significantly but does lead to poorer thermal stability and higher dark current. This work suggests a promising avenue for future high-speed high-responsivity photodetection in the C- to U-bands.

7.
Inorg Chem ; 58(5): 2916-2920, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30784270

RESUMO

Four [Ag-Ag]2+ unit-encapsulated trimetallic cages 1-4 were synthesized from one new tripodal ligand L and silver salts in different solvent systems by a one-pot method. The formation of coordination cages occurred simultaneously with the condensation of amino groups and ketone. The remarkable structural feature of cages 1-4 is their spontaneous incorporation of [Ag-Ag]2+ cationic units. Moreover, the argentophilic interactions are modulated by the uncoordinated amino substituents. The study herein shows that modification and subtle changes of the cage structures could be realized by a one-pot synthetic method.

8.
Inorg Chem ; 58(13): 8657-8664, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31187988

RESUMO

In search of multifunctional metal-organic frameworks (MOFs), redox-active donors and acceptors, namely, tetrathiafulvalene (TTF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ), were concomitantly used as skeletal components with diamagnetic metal nodes (Cd and Zn) to construct unique framework materials. Six isostructural frameworks were synthesized by diffusion of metal salts, TTF(py)4, and either paramagnetic Li(TCNQ) or diamagnetic H2TCNQ. They were characterized by single-crystal X-ray diffraction and FT-IR and UV-vis-NIR spectroscopy, and their physical properties were studied, including two postsynthetic modifications involving crystal-to-crystal transformations following a solid-solution reaction with I2. The highly colored crystals of two isostructural Zn and Cd frameworks contain undulating Cd-TTF(py)4 layers entwined with TCNQ in a chicken-wire net as part of the skeleton of the MOF as well as TCNQ intercalated within the channels, while nitrate anions are occluded within the cavities formed by the pyridine moieties. Reaction with I2 replaces each intercalated TCNQ•- within the channels with I3-. The optical properties and the electron paramagnetic resonance (EPR) spectra indicate the presence of only radical TCNQ•- in the parent compounds, while the magnetic susceptibilities enabled an estimation of the amount of TCNQ•- ( S = 1/2) leading to almost paramagnetic behavior. Solid-state electrochemistry provides evidence of several one-electron redox states corresponding to the electroactive cores.

9.
Inorg Chem ; 57(11): 6218-6221, 2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-29775051

RESUMO

A CuI-MOF was found to be a highly selective visual sensor for recognizing C2H2. Gas chromatography studies indicated that it can be used to effectively remove minor amounts of C2H2 from C2H4/C2H2 mixtures (98:2) and produce highly pure C2H4 (nearly 100%).

10.
Inorg Chem ; 56(3): 1049-1052, 2017 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-28112935

RESUMO

The generation of highly reactive oxygen (1O2) is very significant for a variety of applications such as degradation, bleaching, chemical synthesis, photodynamic therapy for tumor treatment, and others. Herein, we report a novel peroxide-dianion-embedded bimetallic macrocycle, [O22-@Ag4Cu4L4]2+ (2), that can completely release the inserted peroxide dianion as the singlet oxygen (1O2) via a H+-assisted disproportionation process in methanol. Notably, the resulting empty Ag4Cu4L4(ClO4)4 (3) is able to trap oxygen (3O2) from air and fixes it in the macrocycle host as a peroxide dianion; furthermore, it releases it as 1O2 again in the presence of H+. So, the bimetallic macrocycle [Ag4Cu4L4]4+ herein behaves as a highly efficient reusable triplet oxygen receptor and singlet oxygen generator.

11.
Inorg Chem ; 56(21): 13241-13248, 2017 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-28985071

RESUMO

Fluorescent probes are powerful tools for the investigations of reactive oxygen species (ROS) in living organisms by visualization and imaging. As one of the most important of the natural reactive oxygen species (ROS), hypochlorous acid (HClO) plays a crucial role in various physiological and pathological processes. We report herein a new redox-switchable NMOF of UiO-68-ol via a direct ligand modification approach. The obtained UiO-68-ol NPs, which contains organic-based molecular redox switches, exhibit excellent photophysical properties for biological application and can be highly sensitive and selective fluorescent probes to detect HClO species in living cells.


Assuntos
Portadores de Fármacos/farmacologia , Corantes Fluorescentes/farmacologia , Ácido Hipocloroso/análise , Estruturas Metalorgânicas/farmacologia , Nanopartículas/química , Compostos de Urânio/química , Animais , Linhagem Celular Tumoral , Cisteína/metabolismo , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Hidrazinas/metabolismo , Ligantes , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Camundongos , Microscopia Confocal/métodos , Imagem Molecular , Oxirredução , Porosidade
12.
Inorg Chem ; 56(21): 12678-12681, 2017 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-29023109

RESUMO

Neutral N-pyrazolyl radicals [3,5-R2pz]• as reactive intermediates were generated by one-electron oxidization of the corresponding 3,5-disubstituted pyrazolato anions [3,5-R2pz]- (R = tBu, Ph) with BiCl3 and trapped by the use of 5,5-dimethyl-1-pyrroline-N-oxide as a spin trap, which was confirmed by electron paramagnetic resonance spectral analysis. With dimerization of the postulated pyrazolato low-valent BiII radical species, two novel paddlewheel pyrazolatodibismuthanes [L2(Bi-Bi)L2] [L = η1,η1-3,5-R2pz; R = tBu (5α, 5ß, and 5γ), Ph (6)] were isolated and structurally characterized.

13.
Inorg Chem ; 56(4): 2337-2344, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28182424

RESUMO

A bifunctional robust and highly porous imidazolium-based ionic liquid decorated UiO-67 type MOF (UiO-67-IL, 1) was successfully constructed via solvothermal assembly of the imidazolium-based ligand and Zr(IV) ions. It exhibits a highly selective adsorption for CO2 over CH4 and N2. Furthermore, 1 herein can be used as a highly active heterogeneous catalyst for CO2 cycloaddition with epoxides under atmospheric pressure with or without cocatalyst TBAB (n-Bu4NBr).

14.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(10): 1180-1183, 2016 10.
Artigo em Zh | MEDLINE | ID: mdl-30641003

RESUMO

Objective To observe the correlation between the distribution of Chinese medicine (CM) syndromes and CD4 + T lymphocyte counts of acquired immune deficiency syndrome (AIDS) patients in Xin- jiang region. Methods Totally data (four diagnostic information of CM) of 787 HIV+ patients were collected and syndrome typed from 6 places with higher incidence of AIDS (Urumqi region, Aksu region, Turpan region, Yili region, Kashi region, and Bazhou region). CD4 + T lymphocyte counts were detected in AIDS patients with each syndrome. The correlations of CD4 + T lymphocyte counts and distributions of CM syndrome types were ana- lyzed. Results Qi-yin deficiency syndrome (QYDS) and qi deficiency and dampness resistance syndrome (QDDRS) were dominant in AIDS patients in Urumqi region and Aksu region. Gan stagnation qi stasis syn- drome (GSQSS) was more often seen in AIDS patients in Turpan region. QDDRS was more often seen in AIDS patients in Yili Region. Gan-Shen yin deficiency syndrome (GSYDS) was more often seen in AIDS patients in Kashi region. QYDS was more often seen in AIDS patients in Bazhou region. Fei-Shen yin deficiency syndrome (FSYDS) was more often seen in AIDS patients with CD4 T lymphocytes less than 200/µL. FSYDS and qi stag- nation phlegm coagulation syndrome (QSPCS) were more often seen in AIDS patients with CD4+ T lympho- cytes ranging 201 -350/µL. QDDRS and QYDS were more often seen in AIDS patients with CD4 + T lymphocytes ranging 351 -500/µL. Unconsolidated Fei-qi syndrome (UFQS) and Pi-qi deficiency syndrome (PQDS) were more often seen in AIDS patients with CD4+ T lymphocytes more than 501/µL (P <0. 05). Conclusions There existed different T-lymphocyte levels in AIDS patients with various syndrome types of CM in Xinjiang region, with certain correlation. Along with decreased CD4+T lymphocyte counts, AIDS patients' CM syndromes mani- fested a changing process from superficiality to interior syndrome, and from intermingled syndromes of defi- ciency and excess to deficiency syndrome.


Assuntos
Síndrome da Imunodeficiência Adquirida , Medicina Tradicional Chinesa , Qi , Síndrome da Imunodeficiência Adquirida/diagnóstico , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/terapia , Contagem de Linfócito CD4 , Humanos , Síndrome , Deficiência da Energia Yin
15.
Inorg Chem ; 54(22): 10865-72, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26497909

RESUMO

A porous Co(II)-MOF (1) was synthesized by the combination of a bent imidazole-bridged ligand and p-phthalic acid (PTA) with Co(OAc)2 under solvothermal conditions. This Co(II)-MOF (1) is able to undergo a reversible MeOH substitution reaction on the Co(II) center via a single-crystal-to-single-crystal process. The desolvated Co(II)-MOF (2) with the open Co(II) sites is very stable (up to 350 °C). Furthermore, 2 is a highly active heterogeneous catalyst for various organic substrates oxidation in the presence of tert-butyl hydroperoxide (TBHP) under milder conditions. The importance of open Co(II) sites in 2 for the organic substrates oxidation is directly evidenced by the single-crystal X-ray diffraction.

16.
Inorg Chem ; 54(24): 11590-2, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26645672

RESUMO

A porous Cu(I)-MOF [H2O⊂Cu2(L)2I2; L = 1-benzimidazolyl-3,5-bis(4-pyridyl)benzene], which can be a visual and luminescent sensor for detecting small polar aliphatic volatile organic compounds (VOCs), such as alcohols, ketones, and halocarbons, is reported. The naked-eye and luminescent detection limitations for these VOCs are 5 and 1 ppm, respectively.

17.
Inorg Chem ; 53(20): 10791-3, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25260017

RESUMO

A solid-state simultaneous exchange of metal nodes and counteranions based on a cobalt(2+) coordination polymer is reported for the first time. The ion-exchange process is visual, and the structural integrity of the cobalt(2+) coordination polymer is maintained during the ion-exchange process.

18.
Inorg Chem ; 53(17): 9087-94, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25116406

RESUMO

A series of isostructural 2-fold interpenetrating 2D Cd(II)-MOFs, namely G⊂CdL2(OTs)2 (G = THF (1), PhF (2), PhCl (3), PhBr (4), PhI (5), L = 1,2-bis[(3-(pyridin-4-yl)phenoxy]ethane, and OTs(-) = p-toluenesulfonate anion), have been successfully synthesized from the flexible ethylene glycol ether-bridging ligand L and Cd(OTs)2 in solution. The CdL2(OTs)2 framework contains squarelike nonpolar channels, and the encapsulated guest molecules can be removed by heating (150 °C) to generate a guest-free host framework which is able to reversibly adsorb monohalobenzenes PhX (X = F, Cl, Br, I) in the liquid phase under ambient conditions without loss of framework integrity. Furthermore, it can effectively separate these monohalobenzenes and exhibits a clear affinity for monohalobenzenes according to the following order: PhI > PhBr > PhCl > PhF. In addition, PhX⊂CdL2(OTs)2 exhibits guest-dependent luminescence properties.


Assuntos
Benzeno/química , Cádmio/química , Halogênios/química , Adsorção , Luminescência , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Infravermelho
19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(7): 816-8, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25137847

RESUMO

OBJECTIVE: To investigate the tongue manifestation features of sexually transmitted and intravenous drug use spread HIV infected population in Xinjiang. METHODS: Recruited were 990 HIV infected subjects in Xinjiang from May 2011 to March 2012, who were assigned to the intravenous drug use spread HIV infected (498 cases) and the sexually transmitted (492 cases). By using tongue figure shoot combined with analyses of experts, tongue manifestations were analyzed and compared between the sexually transmitted and the intravenous drug use spread from four aspects, i.e., the tongue color, the tongue shape, the fur color, and the fur property. RESULTS: Compared with the sexually transmitted population, red tongue, fissured tongue, yellow fur, thick fur, eroded fur, deficiency of fur fluid were more often seen, showing statistical difference (P < 0.05). Compared with the intravenous drug use spread population, pale tongue, white fur, and thin fur were more often seen, showing statistical difference (P < 0.05). CONCLUSIONS: The tongue manifestations of the intravenous drug use spread HIV population reflected inner exuberance of evil toxin and heat impairing qi and yin. Compared with the intravenous drug use spread population, the attack of HIV infection was more hiding in the sexually transmitted population, with milder internal injury. Their Wei-qi was not damaged and no obvious change occurred in the tongue figure.


Assuntos
Infecções por HIV/patologia , Medicina Tradicional Chinesa , Língua/patologia , Adolescente , Adulto , Idoso , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Virais Sexualmente Transmissíveis/diagnóstico , Doenças Virais Sexualmente Transmissíveis/patologia , Transtornos Relacionados ao Uso de Substâncias/complicações , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adulto Jovem
20.
Eur J Med Chem ; 264: 115997, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38056303

RESUMO

The suppression of ferroptosis is emerging as a promising therapeutic strategy for effectively treating a wide range of diseases, including neurodegenerative disorders, organ ischemia-reperfusion injury, and inflammatory conditions. However, the clinical utility of ferroptosis inhibitors is significantly impeded by the limited availability of rational drug designs. In our previous study, we successfully unraveled the efficacy of ferrostatin-1 (Fer-1) attributed to the synergistic effect of its ortho-diamine (-NH) moiety. In this study, we present the discovery of the ortho-hydroxyl-amino moiety as a novel scaffold for ferroptosis inhibitors, employing quantum chemistry as well as in vitro and in vivo assays. 2-amino-6-methylphenol derivatives demonstrated remarkable inhibition of RSL3-induced ferroptosis, exhibiting EC50 values ranging from 25 nM to 207 nM. These compounds do not appear to modulate iron homeostasis or lipid reactive oxygen species (ROS) generation pathways. Nevertheless, they effectively prevent the accumulation of lipid peroxides in living cells. Furthermore, compound 13 exhibits good in vivo activities as it effectively protect mice from kidney ischemia-reperfusion injury. In summary, compound 13 has been identified as a potent ferroptosis inhibitor, warranting further investigation as a promising lead compound.


Assuntos
Peróxidos Lipídicos , Traumatismo por Reperfusão , Animais , Camundongos , Peroxidação de Lipídeos , Peróxidos Lipídicos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Fenóis/farmacologia
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