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1.
J Am Chem Soc ; 145(32): 17588-17596, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37454391

RESUMO

Organic dyes as non-noble metal photosensitizers have attracted increasing attention due to their environmental friendliness and sustainability but suffer from fast deactivation and low stability. Here, we reported a fruitful strategy by the confinement and stabilization of visible light-active signal unit organic dyes within the metal-organic frameworks (MOFs) and developed a series of heterogeneous photocatalysts dye@UiO-66s [dye = fluorescein (FL)/rhodamine B (RhB)/eosin Y (EY), UiO-66s = UiO-66, and Bim-UiO-66]. It has been demonstrated that the encapsulated dyes can effectively sensitize MOF hosts and dominate the band structures and photocatalytic activities of dye@UiO-66s regardless of the ligand functionalization of MOFs. Photocatalytic experiments showed that these dye@UiO-66s exhibit enhanced activities relative to free dyes and among them, FL@Bim-UiO-66 displays excellent efficiencies toward the green synthesis of new carbon-bridged annulations, [1,2,5]thiadiazole[3,4-g]benzoimidazoles in the yield of up to 98% at room temperature with outstanding stability and reusability. Furthermore, the intramolecular cyclization intermediate was captured and characterized by the single-crystal X-ray diffraction analysis.

2.
Inorg Chem ; 62(42): 17182-17190, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37815498

RESUMO

Oxidation and removal of highly toxic sulfides and amines are particularly important for environmental and human security but remain challenging. Here, incorporating an excellent photosensitizer, donor-acceptor-donor (D-A-D)-type 4,4'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic (H2L), into metal-organic frameworks (MOFs) has been manifested to promote the charge separation, affording four three-dimensional (3D) MOFs (isostructural 1-Co/1-Zn with Co2/Zn2 units, and 2-Gd/2-Tb with Gd/Tb-cluster chains) as photocatalysts in the visible light-driven air-O2-mediated catalytic oxidation and removal of hazardous phenylsulfides and benzylamines. Impressively, structure-property correlation illustrated that the transition metal centers assembled in MOFs play an important role in the photocatalytic activity, and we can conclude that 1-Zn can be a robust heterogeneous catalyst possessing good light adsorption and fast charge separation in oxidation removal reactions of both benzylamines and phenylsulfides under visible light irradiation and room temperature with excellent activity/selectivity, stability, and reusability.

3.
Chem Biodivers ; 20(9): e202300556, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37469185

RESUMO

In this article, two undescribed amides (1-2) with an unusual (2-formyl-5-hydroxymethyl)pyrroyl-butylamine moiety were obtained from the Physochlainae Radix. Comprehensive spectroscopic studies, including NMR and HR-ESI-MS, coupling with spectroscopic data comparisons were used to determine structures. Anti-inflammatory assay results showed that new amides possessed significant inhibitory activities of the NO production of LPS-induced RAW 264.7 cells, with IC50 values of 17.52±1.68 µM and 20.37±2.42 µM, respectively.


Assuntos
Amidas , Anti-Inflamatórios , Animais , Camundongos , Amidas/farmacologia , Anti-Inflamatórios/farmacologia , Células RAW 264.7 , Estrutura Molecular
4.
Inorg Chem ; 61(30): 11992-12002, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35866632

RESUMO

Effective and rapid capture of heavy metal oxo-anions from wastewater is a fascinating research topic, but it remains a great challenge. Herein, benzimidazole and -CH3 groups were integrated into UiO-66 in succession via a step-by-step linker modification strategy that was performed by presynthesis modification (to give Bim-UiO-66) and subsequently by postsynthetic ionization (to give Bim-UiO-66-Me). The UiO-66s (UiO-66, Bim-UiO-66, and Bim-UiO-66-Me) were applied in the removal of heavy metal oxo-anions from water. The two benzimidazole derivatives (Bim-UiO-66 and Bim-UiO-66-Me) showed much better performance than UiO-66, as both the initial sorption rate and sorption capacities decreased in the order Bim-UiO-66-Me > Bim-UiO-66 > UiO-66. The maximum performances of Bim-UiO-66 are 5.1 and 1.7 times those of UiO-66. Remarkably, Bim-UiO-66-Me shows 7.5 and 3.0 times better performance than UiO-66. The higher absorptivity of cationic Bim-UiO-66-Me compared with UiO-66 can be attributed to a strong Coulombic interaction as well as an anion-π interaction and hydrogen bonding between the benzimidazolium functional group and heavy metal oxo-anions. The as-synthesized Bim-UiO-66-Me not only provides a promising candidate for application in removal of heavy metal oxo-anions in wastewater treatment but also opens up a new strategy for the design of high-performance adsorbents.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Ânions , Benzimidazóis , Cátions , Estruturas Metalorgânicas , Ácidos Ftálicos , Poluentes Químicos da Água/análise
5.
Org Biomol Chem ; 20(29): 5845-5851, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35848391

RESUMO

A metal-free inactive C(sp3)-H bond functionalization of thioethers with styrenes using TBHP as an initiator and DBU as a base has been developed. This transformation has broken through the low activity of thioethers and realized moderate yields. Herein extended experiments were conducted to confirm the radical relay process, reaction energy and intermediate transformations.

6.
Mamm Genome ; 32(2): 115-122, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33755782

RESUMO

Atherosclerosis was an important pathophysiological basis of atherothrombotic stroke, and phosphodiesterase 4D (PDE4D) polymorphism (SNP83/rs966221) was reported to be associated with the susceptibility to atherothrombotic stroke. Aim of the present study was to explore the potential association between SNP83 and carotid atherosclerosis (CAS). 204 southern Chinese Han participants were divided into two groups according to the carotid intima-media thickness (IMT) of the carotid artery: CAS group (carotid IMT ≥ 1.0 mm) and non-CAS group (carotid IMT < 1.0 mm). Carotid IMT was measured by color Doppler ultrasound. The PDE4D SNP83 polymorphism was determined by SNaPshot technique. Our study found that SNP83 was associated significantly with CAS susceptibility under the dominant, overdominant and codominant models. After adjusting for age, gender, low-density lipoprotein cholesterol, Hemoglobin A1c, cigarette smoking, hypertension history, and diabetes mellitus history, the association still remained significant (dominant model: crude OR = 2.373, 95% CI: 1.268-4.442, P = 0.007; adjusted OR = 3.129, 95% CI: 1.104-8.866, P = 0.032; overdominant model: crude OR = 1.968, 95% CI: 1.043-3.714, P = 0.037; adjusted OR = 2.854, 95% CI: 1.005-8.108, P = 0.049; codominant: crude OR = 2.102, 95% CI: 1.110-3.979, P = 0.023; adjusted OR = 2.984, 95% CI: 1.047-8.502, P = 0.041). Carotid IMT of carriers with CT + CC genotypes was higher than carriers with TT genotype (P = 0.016). Our results indicated that the SNP83/rs966221 located on PDE4D gene was significantly associated between CAS susceptibility and carotid IMT independently of conventional risk factors in a southern Chinese Han population.


Assuntos
Povo Asiático/genética , Doenças das Artérias Carótidas/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Alelos , Biomarcadores , Doenças das Artérias Carótidas/diagnóstico , Espessura Intima-Media Carotídea , China , Estudos de Associação Genética , Genótipo , Humanos , Fatores de Risco
7.
Phys Chem Chem Phys ; 21(5): 2804-2815, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30667421

RESUMO

The construction route of organic superacids from the combination of organic superhalogens and protons is verified to be a rational one based on a systematic theoretical study covering different planar conjugated backbones, e.g., [C5H5]- and [BC5H6]-, and electron-withdrawing substituents, e.g., -F, -CN and -NO2. In both the gas phase and the solution phase, the acidities of the composites here have a consistent strengthening with the increase of the vertical electron detachment energy of the superhalogen part. Decomposition of the acidity into different contributions further verifies the dominant role of the superhalogen part in the variation of the acidity. Thus, tuning of the acidity of systems of this type could be achieved via rational design of the constituent part of the superhalogen. That is to say, the design of a novel organic superacid with enhanced properties could be guided by the search for a new strong superhalogen of organic nature eventually. Having provided important contributions to the topic of superhalogens, theoretical calculation should be trusted to provide useful guidance for the research of organic superacids and could be expected to promote related experimental studies in the near future.

8.
Lipids Health Dis ; 18(1): 233, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31883534

RESUMO

BACKGROUND: Previous genome-wide association studies have found two single nucleotide polymorphisms (SNP) rs7692387 and rs1842896 located on or near the GUCY1A3 gene were associated with coronary artery disease (CAD). GUCY1A3 was considered to be involved in the process of atherosclerosis, but there was little information about the association between genotypic polymorphisms of the GUCY1A3 and large artery atherosclerotic (LAA) stroke. This study aimed to investigate the associations between the GUCY1A3 rs7692387, rs1842896 polymorphisms and LAA stroke susceptibility. METHODS: A total of 298 LAA stroke patients and 300 control subjects from a southern Chinese Han population were included. SNaPshot technique was used for genotype analysis. Associations between genotypes and LAA stroke susceptibility were analyzed with logistic regression model. RESULTS: Our study found that under the recessive model (TT vs. GT + GG), the GUCY1A3 rs1842896 polymorphism was significantly correlated with LAA stroke (OR = 1.48, 95%CI: 1.07-2.04, P = 0.018). After adjustment for its effects on age, gender, cigarette smoking, total cholesterol, low-density lipoprotein cholesterol, HbA1c, hypertension, diabetes mellitus, and CAD, the rs1842896 TT genotype retained association with increased susceptibility to LAA stroke (recessive model: adjusted OR = 1.96, 95%CI: 1.22-3.17, P = 0.006). However, association between rs7692387 polymorphism with LAA stroke was not observed. CONCLUSION: Our results indicate that the GUCY1A3 rs1842896 polymorphism is an LAA stroke risk factor in Southern Han Chinese.


Assuntos
Aterosclerose/genética , Hipertensão/genética , Guanilil Ciclase Solúvel/genética , Acidente Vascular Cerebral/genética , Idoso , Artérias/patologia , Aterosclerose/epidemiologia , Aterosclerose/patologia , China/epidemiologia , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Hipertensão/epidemiologia , Hipertensão/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/patologia
9.
J Chem Phys ; 149(6): 064301, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30111124

RESUMO

A series of 20 composite structures, consisting of superhalogen and noble gas (Ng) hydrides, was explored via high-level coupled-cluster single, double and perturbative triple excitations calculations in this work. The existence of these composites, as local minima on the potential energy surface, arises from the charge transfer from the Ng hydride part to the superhalogen moiety. Clearly, this transfer could lead to stabilizing the interaction of the ionic type between the two components. The driving force of the charge transfer should be the high vertical electron detachment energy (VDE) of the superhalogen part leading to its enough capability of extracting the electron from the Ng hydride moiety. However, except triggering the ionic attractive interaction, there is nomonotonic correlation between the VDE value and the thermodynamic stability of the whole composite. This counter-intuitive result actually originates from the fact that, irrespective of various superhalogens, only two of their F ligands interact with the Ng atoms directly. Thus, although leading to higher VDE values, the increase in the number of electronegative ligands of the superhalogen moiety does not affect the stabilizing interaction of the composites here directly. In other words, with the necessary charge transfer generated, further increase of the VDE does not ensure the improvement of the thermodynamic stabilities of the whole composite. Moreover, in the transition state of the exothermic dissociation channel, more F atoms will give rise to higher probability of additional attractions between the F and H atoms which should lower the energy barrier. That is to say, increasing VDE, i.e., having more F atoms in many cases, will probably reduce the kinetic stability. Knowing the inevitable existence of the exothermic channel, kinetic stability is crucial to the ultimate goal of experimental observation of these Ng hydrides. Thus, in some cases, only the superhalogen itself may not provide enough information for the correct prediction on the properties of the whole composites. The understanding of the superhalogen-based composites will provide valuable information on the functional properties as well as the application potential of superhalogen clusters. Thus, the corresponding researches should focus on not only the superhalogen itself but also other related aspects, especially the details of the interaction between different parts.

10.
Zhongguo Zhong Yao Za Zhi ; 42(12): 2236-2246, 2017 Jun.
Artigo em Zh | MEDLINE | ID: mdl-28822175

RESUMO

Plant tissue culture technology has been widely used in the field of traditional Chinese medicine(TCM) resources with its unique advantages, playing an important role in the protection of TCM resources. In this review, some applications of plant tissue culture were summarized, including production of active compounds by using plant tissue culture, genetic diversity analysis, Dao-di herbs, elicitor application, biosynthesis and transgenic plants. Through the above researches will promote the further development of plant tissue culture technology, making it play a greater role in the field of TCM resources.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos , Medicina Tradicional Chinesa , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
11.
Phys Chem Chem Phys ; 18(41): 28576-28584, 2016 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-27711649

RESUMO

The potential of 23 superhalogen anions of halogen-free structures as high-performance electrolytes of Li-ion batteries is theoretically explored here. According to high-level ab initio results at the CCSD(T) level, eight candidates, obeying the Wade-Mingos rule, should be capable of forming electrolytes, which are better than the currently used commercial products. When comparing different methods, MP2 was found to be in good agreement with CCSD(T) in the calculation of ΔELi+ and ΔEH2O, which are parameters describing the performance of potential electrolytes. Thus, MP2 represents a good choice for such calculations, particularly for large potential electrolyte systems wherein CCSD(T) calculations are actually impractical. The five functionals selected here (ωB97XD, B2GP-PLYP, B2K-PLYP, B2T-PLYP and B3LYP) are also capable of reproducing the variational trends of the relative values of different structures at the CCSD(T) level. However, the actual DFT values of ΔELi+ are usually different from those of CCSD(T) by more than 1 eV. These significant deviations may be a problem when accurate ΔELi+ values are required.

12.
J Chem Phys ; 144(5): 054303, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26851917

RESUMO

A systematic density functional theory study including 17 exchange-correlation functionals was performed on different types of superhalogens with high level coupled-cluster single double including perturbative triple excitations (CCSD(T)) results as the reference. The superhalogens selected here cover the ranges from mononuclear to polynuclear structures and from structures with halogen-atom ligands to those with non-halogen ligands, e.g., [MgX3](-), [Mg2X5](-), and [Mg3X7](-) (X = F, Cl, CN). It is clearly indicated that three double-hybrid functionals B2T-PLYP, B2GP-PLYP, B2K-PLYP as well as the range-separated hybrid functional ωB97X are capable of providing results which approach the accuracy at the CCSD(T) level. The basis set effect is usually moderate and, in most cases, it is enough to utilize the basis set of triple-ξ quality, e.g., Def2-TZVP. In addition, the results of the HF and MP2 method are also acceptable here, especially for polynuclear superhalogens where CCSD(T) is probably unpractical.

13.
Chemistry ; 21(12): 4703-11, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25663637

RESUMO

The 1D complex [(CuL0.5H2O)⋅H2O]n (1) (H4L = 2,2'-bipyridine-3,3',6,6'-tetracarboxylic acid) undergoes an irreversible thermally triggered single-crystal-to-single-crystal (SCSC) transformation to produce the 3D anhydrous complex [CuL0.5]n (2). This SCSC structural transformation was confirmed by single-crystal X-ray diffraction analysis, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) patterns, variable-temperature powder X-ray diffraction (VT-PXRD) patterns, and IR spectroscopy. Structural analyses reveal that in complex 2, though the initial 1D chain is still retained as in complex 1, accompanied with the Cu-bound H2O removed and new O(carboxyl)-Cu bond forming, the coordination geometries around the Cu(II) ions vary from a distorted trigonal bipyramid to a distorted square pyramid. With the drastic structural transition, significant property changes are observed. Magnetic analyses show prominent changes from antiferromagnetism to weak ferromagnetism due to the new formed Cu1-O-C-O-Cu4 bridge. The catalytic results demonstrate that, even though both solid-state materials present high catalytic activity for the synthesis of 2-imidazolines derivatives and can be reused, the activation temperature of complex 1 is higher than that of complex 2. In addition, a possible pathway for the SCSC structural transformations is proposed.

14.
Chemphyschem ; 16(17): 3652-9, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26337156

RESUMO

An ab initio study of the superhalogen properties of eighteen binuclear double-bridged [Mg2 (CN)5 ](-1) clusters is reported herein by using various theoretical methods. High-level CCSD(T) results indicate that all the clusters possess strong superhalogen properties owing to their high vertical electron detachment energies (VDEs), which exceed 6.8 eV (highest: 8.15 eV). The outer valence Green's function method provides inaccurate relative VDE values; hence, this method is not suitable for this kind of polynuclear superhalogens. Both the HF and MP2 results are generally consistent with the CCSD(T) level regarding the relative VDE values and-especially interesting-the average values of the HF and MP2 VDEs are extremely close to the CCSD(T) results. The distributions of the extra electrons of the anions are mainly aggregated into the terminal CN units. These distributions are apparently different from those of previously reported triple-bridged isomers and may be the reason for the decreased VDE values of the clusters. In addition, comparisons of the VDEs of binuclear and mononuclear superhalogens as well as studies of the thermodynamic stabilities with respect to the detachment of various CN(-1) ligands are also performed. These results confirm that polynuclear structures with pseudohalogen ligands can be considered as probable new superhalogens with enhanced properties.

15.
Phys Chem Chem Phys ; 17(31): 20338-46, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26194876

RESUMO

The regulation of the electronic properties of organic molecules induced by polynuclear superhalogens is theoretically explored here for sixteen composite structures. It is clearly indicated by the higher vertical electron detachment energy (VDE) that polynuclear superhalogens are more effective in regulating the electronic properties than mononuclear structures. However, this enhanced regulation is not only determined by superhalogens themselves but also related to the distribution of the extra electron of the final composites. The composites, in which the extra electron is mainly aggregated into the superhalogen moiety, will possess higher VDE values, as reported in the case of C1', 7.12 eV at the CCSD(T) level. This is probably due to the fact that, compared with organic molecules, superhalogens possess stronger attraction towards the extra electron and thus should lead to lower energies of the extra electrons and to higher VDE values eventually. Compared with CCSD(T), the Outer Valence Green's Function (OVGF) method fails completely for composite structures containing Cl atoms, while MP2 results are generally consistent in terms of the relative order of VDEs. Actually if the extra electron distribution of the systems could be approximated by the HOMO, the results at the OVGF level will be consistent with the CCSD(T) results. Conversely, the difference in VDEs between OVGF and CCSD(T) is significantly large. Besides superhalogen properties, the structures, relative stabilities and thermodynamic stabilities with respect to various fragmentation channels were also investigated for all the composite structures.

16.
J Chem Phys ; 140(9): 094301, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24606355

RESUMO

The first theoretical exploration of superhalogen properties of polynuclear structures based on pseudohalogen ligand is reported here via a case study on eight triply-bridged [Mg2(CN)5](-) clusters. From our high-level ab initio results, all these clusters are superhalogens due to their high vertical electron detachment energies (VDE), of which the largest value is 8.67 eV at coupled-cluster single double triple (CCSD(T)) level. Although outer valence Green's function results are consistent with CCSD(T) in most cases, it overestimates the VDEs of three anions dramatically by more than 1 eV. Therefore, the combined usage of several theoretical methods is important for the accuracy of purely theoretical prediction of superhalogen properties of new structures. Spatial distribution of the extra electron of high-VDE anions here indicates two features: remarkable aggregation on bridging CN units and non-negligible distribution on every CN unit. These two features lower the potential and kinetic energies of the extra electron respectively and thus lead to high VDE. Besides superhalogen properties, the structures, relative stabilities and thermodynamic stabilities with respect to detachment of CN(-1) were also investigated for these anions. The collection of these results indicates that polynuclear structures based on pseudohalogen ligand are promising candidates for new superhalogens with enhanced properties.

17.
Fitoterapia ; 174: 105828, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38296166

RESUMO

Aster tataricus L.f. is highly valued for its rich reserves of bioactive compounds. Our research focused on the identification of previously unreported compounds found within the ethanol extract of A. tataricus. Through meticulous spectroscopic analyses and computational methods like NMR calculations and ECD, we successfully elucidated the structures of five novel compounds termed tatarisides A-E (1-5), alongside two known compounds (6, 7). The anti-inflammatory assays conducted yielded noteworthy results, particularly in relation to compounds 1 and 5. These compounds exhibited significant potential in inhibiting the release of NO in LPS-induced RAW 264.7 cells, as evidenced by their respective IC50 values of 17.81 ± 1.25 µM and 13.32 ± 0.84 µM. The discovery of these new compounds adds to the existing knowledge of A. tataricus's chemical composition and potential applications.


Assuntos
Aster , Estrutura Molecular , Aster/química , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Etanol
18.
Wien Klin Wochenschr ; 136(1-2): 67-72, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37389688

RESUMO

BACKGROUND: Neuronal intranuclear inclusion disease (NIID) is a rare highly heterogeneous disease. In this paper, we present a case of NIID featured in cortical involvement in left hemisphere of brain and the imaging changes in the process of the disease. CASE PRESENTATION: A 57-year-old female was hospitalized due to recurrent attacks of headache with cognitive impairment and tremor for 2 years. The symptoms of headache episodes were reversible. The characteristic radiologic change was high intensity signal involving the grey matter-white matter junction on the brain diffusion-weighted imaging (DWI), which existed in the frontal lobe and then extended backwards. Atypical features on fluid-attenuated inversion recovery (FLAIR) sequences showing small patchy high signals in the cerebellar vermis. High signals and edema were detected on FLAIR images along the cortex of the left occipito-parieto-temporal lobes, expanding and gradually shrinking in the follow-up visit. Besides, cerebral atrophy and bilateral symmetrical leukoencephalopathy were also detected. Skin biopsy and genetic testing confirmed the diagnosis of NIID. CONCLUSION: Except for typical radiological change strongly suggesting NIID, it is also necessary to notice the insidious symptoms of NIID combining with some atypical imaging features to make an early diagnosis. Skin biopsies or genetic testing should be carried out early in patients with highly suspected NIID.


Assuntos
Doenças Neurodegenerativas , Feminino , Humanos , Pessoa de Meia-Idade , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/patologia , Imageamento por Ressonância Magnética , Imagem de Difusão por Ressonância Magnética , Cefaleia
19.
J Chem Phys ; 139(5): 054305, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23927260

RESUMO

The structures, relative stabilities, vertical electron detachment energies, and magnetic properties of a series of trinuclear clusters are explored via combined broken-symmetry density functional theory and ab initio study. Several exchange-correlation functionals are utilized to investigate the effects of different halogen elements and central atoms on the properties of the clusters. These clusters are shown to possess stronger superhalogen properties than previously reported dinuclear superhalogens. The calculated exchange coupling constants indicate the antiferromagnetic coupling between the transition metal ions. Spin density analysis demonstrates the importance of spin delocalization in determining the strengths of various couplings. Spin frustration is shown to occur in some of the trinuclear superhalogens. The coexistence of strong superhalogen properties and spin frustration implies the possibility of trinuclear superhalogens working as the building block of new materials of novel magnetic properties.

20.
Zhongguo Zhen Jiu ; 43(7): 751-5, 2023 Jul 12.
Artigo em Zh | MEDLINE | ID: mdl-37429652

RESUMO

OBJECTIVE: To observe the effects of transcutaneous acupoint stimulation (TEAS) on sleep quality and inflammatory factor in frail elderly patients undergoing laparoscopic colorectal cancer surgery. METHODS: A total of 100 frail elderly patients undergoing elective laparoscopic colorectal cancer surgery were randomly divided into an observation group and a control group, 50 cases in each one. Patients in the observation group received TEAS, 30 min before surgery until the end of surgery, at 18:00 on the day of surgery and on the 1st, 2nd and 3rd day after surgery (30 min each time). TEAS was delivered at bilateral Neiguan (PC 6), Shenmen (HT 7) and Hegu (LI 4). The disperse-dense wave of 2 Hz/100 Hz was selected, and the maximal stimulation intensity depended on patient's tolerance. The operation procedure in the control group was same as the observation group, but without electric stimulation exerted. The 1st day before surgery and on the 1st, 3rd and 7th day after surgery, the scores of Pittsburgh sleep quality index (PSQI) and Athens insomnia scale (AIS), as well as the serum levels of C reactive protein (CRP) and interleukin-6 (IL-6) were observed in the patients of two groups. At 24 h, 48 h and 72 h after surgery, the score of pain visual analogue scale (VAS) was recorded in the two groups, as well as the pressing times of analgesic pump and the usage of flurbiprofen axetil during analgesic stage. The occurrence of post operative adverse reactions was observed in the patients of two groups. RESULTS: On the 1st and 3rd day after surgery, except the usage of hypnotic drug scores, the scores of each item and the total scores of PSQI, as well as AIS scores were all increased in the two groups compared with those of 1 day before surgery (P<0.05); and the scores in the observation group were lower than those in the control group (P<0.05). On the 7th day after surgery, the scores of each item and the total scores of PSQI, and AIS scores were not different statistically in comparison between the two groups (P>0.05). On the 1st, 3rd and 7th day after surgery, serum levels of CRP and IL-6 were all increased in the patients of two groups when compared with those of 1 day before surgery (P<0.05), serum levels CRP and IL-6 in the patients of the observation group were lower than those of the control group (P<0.05). The VAS scores of 24 h, 48 h and 72 h after surgery, the pressing times of analgesic pump, the frequency and dosage of the remedies were not different statistically between the two groups (P>0.05). CONCLUSION: TEAS can effectively improve sleep quality and reduce inflammatory reaction in frail elderly patients undergoing laparoscopic colorectal cancer surgery.


Assuntos
Pontos de Acupuntura , Neoplasias Colorretais , Idoso , Humanos , Idoso Fragilizado , Interleucina-6 , Qualidade do Sono , Proteína C-Reativa
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