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1.
Sci Data ; 11(1): 304, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503792

RESUMO

Massive increases in the risks of depressive disorders and the ensuing suicide have become the overarching menace for children/adolescents. Despite global consensus to instigate psychological healthcare policy for these children/adolescents, their effects remain largely unclear neither from a small amount of official data nor from small-scale scientific studies. More importantly, in underprivileged children/adolescents in lower-middle-economic-status countries/areas, the data collection may not be as equally accessible as in developed countries/areas, thus resulting in underrepresented observations. To address these challenges, we released a large-scale and multi-center cohort dataset (n = 249,772) showing the effects of primary psychological healthcare on decreasing depression and suicidal ideation in these children/adolescents who were underrepresented in previous studies or current healthcare systems, including unattended children/adolescents, orphans, children/adolescents in especially difficult circumstances, and "left-behind" and "single-parenting" children/adolescents. We provided all individual data recording the depressive symptoms and suicide ideation that had been collected at baseline (Oct 2022) and half-year follow-up (May 2023) from practicing this psychological healthcare system.


Assuntos
Depressão , Ideação Suicida , Adolescente , Criança , Humanos , Depressão/psicologia , Depressão/terapia , Fatores Socioeconômicos , Estudos Multicêntricos como Assunto
2.
J Org Chem ; 89(7): 4406-4422, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38512313

RESUMO

The palladium-catalyzed sequential cross-coupling/annulation of ortho-vinyl bromobenzenes with aryl bromides generating phenanthrenes was characterized by density functional theory (DFT). The Pd(II)-Pd(IV) pathway (Path V) is shown to be less probable than the bimetallic pathway (Path I), the latter proceeding via the following six steps: oxidative addition, vinyl-C(sp2)-H activation, Pd(II)-Pd(II) transmetalation, C-C coupling, aryl-C(sp2)-H activation, and reductive elimination. The aryl-C(sp2)-H activation process acts as the rate-determining step (RDS) of the entire chemical transformation, with an activation free energy barrier of ca. 27.4-28.8 kcal·mol-1, in good agreement with the corresponding experimental data (phenanthrenes' yields of ca. 65-90% at 130 °C after 5 h of reaction). The K2CO3 additive effectively reduces the activation free energy barrier of the RDS through direct participation in the reaction while preferentially modulating the charge distributions and increasing the stability of corresponding intermediates and complexes along the reaction path. Furthermore, bonding and electronic structure analyses of the key structures indicate that the chemo- and regioselectivities of the reaction are strongly influenced by both electronic effects and steric hindrance.

3.
Inorg Chem ; 63(14): 6276-6284, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38546717

RESUMO

Molecules with high point-group symmetry are interesting prototype species in the textbook. As transition metal-centered boron clusters tend to have highly symmetric structures to fulfill multicenter bonding and high stability, new boron clusters with rare point-group symmetry may be viable. Through in-depth scrutiny over the structures of experimentally already observed transition metal-centered boron-wheel complexes, geometric and electronic design principles are summarized, based on which we studied M©B11k- (M = Y, La; Zr, Hf; k = 1, 2) clusters and found that a Y©B112- boron-wheel complex has an unprecedented D11h point-group symmetry. The remarkable stability of the planar Y©B112- complex is illustrated via extensive global-minimum structural search as well as comprehensive chemical bonding analyses. Similar to other boron-wheel complexes, the Y©B112- complex is shown to possess σ and π double aromaticity, indeed following the electronic design principle previously summarized. This new compound is expected to be experimentally identified, which will extend the currently known largest possible planar molecular symmetry and enrich the metal-centered boron-wheel class.

4.
ESC Heart Fail ; 10(6): 3311-3329, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37641543

RESUMO

AIMS: We aim to explore the role and mechanism of vagus nerve stimulation (VNS) in coronary endothelial cells and angiogenesis in infarcted hearts. METHODS AND RESULTS: Seven days after rat myocardial infarction (MI) was prepared by ligation of the left anterior descending coronary artery, the left cervical vagus nerve was treated with electrical stimulation 1 h after intraperitoneal administration of the α7-nicotinic acetylcholine inhibitor mecamylamine or the mAChR inhibitor atropine or 3 days after local injection of Ad-shSDF-1α into the infarcted heart. Cardiac tissue acetylcholine (ACh) and serum ACh, tumour necrosis factor α (TNF-α), interleukin 1ß (IL-1ß) and interleukin 6 (IL-6) levels were detected by ELISA to determine whether VNS was successful. An inflammatory injury model in human coronary artery endothelial cells (HCAECs) was established by lipopolysaccharide and identified by evaluating TNF-α, IL-1ß and IL-6 levels and tube formation. Immunohistochemistry staining was performed to evaluate CD31-positive vessel density and stromal cell-derived factor-l alpha (SDF-1α) expression in the MI heart in vivo and the expression and distribution of SDF-1α, C-X-C motif chemokine receptor 4 and CXCR7 in HCAECs in vitro. Western blotting was used to detect the levels of SDF-1α, V-akt murine thymoma viral oncogene homolog (AKT), phosphorylated AKT (pAKT), specificity protein 1 (Sp1) and phosphorylation of Sp1 in HCAECs. Left ventricular performance, including left ventricular systolic pressure, left ventricular end-diastolic pressure and rate of the rise and fall of ventricular pressure, should be evaluated 28 days after VNS treatment. VNS was successfully established for MI therapy with decreases in serum TNF-α, IL-1ß and IL-6 levels and increases in cardiac tissue and serum ACh levels, leading to increased SDF-1α expression in coronary endothelial cells of MI hearts, triggering angiogenesis of MI hearts with increased CD31-positive vessel density, which was abolished by the m/nAChR inhibitors mecamylamine and atropine or knockdown of SDF-1α by shRNA. ACh promoted SDF-1α expression and its distribution along with the branch of the formed tube in HCAECs, resulting in an increase in the number of tubes formed in HCAECs. ACh increased the levels of pAKT and phosphorylation of Sp1 in HCAECs, resulting in inducing SDF-1α expression, and the specific effects could be abolished by mecamylamine, atropine, the PI3K/AKT blocker wortmannin or the Sp1 blocker mithramycin. Functionally, VNS improved left ventricular performance, which could be abolished by Ad-shSDF-1α. CONCLUSIONS: VNS promoted angiogenesis to repair the infarcted heart by inducing SDF-1α expression and redistribution along new branches during angiogenesis, which was associated with the m/nAChR-AKT-Sp1 signalling pathway.


Assuntos
Infarto do Miocárdio , Estimulação do Nervo Vago , Ratos , Humanos , Camundongos , Animais , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Acetilcolina , Células Endoteliais/metabolismo , Fator de Necrose Tumoral alfa , Mecamilamina , Interleucina-6 , Fosfatidilinositol 3-Quinases , Células Estromais/metabolismo , Células Estromais/patologia , Derivados da Atropina
5.
Dalton Trans ; 52(30): 10609-10620, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37462420

RESUMO

Regioselective B-H activation of o-carboranes is an effective way for constructing o-carborane derivatives, which have broad applications in medicine, catalysis and the wider chemical industry. However, the mechanistic basis for the observed selectivities remains unresolved. Herein, a series of density functional theory (DFT) calculations were employed to characterise the palladium N-heterocyclic carbene (Pd-NHC) catalysed regioselective B(3,6)-diarylation of o-carboranes. Computational results at the IDSCRF(ether)-LC-ωPBE/BS1 and IDSCRF(ether)-LC-ωPBE/BS2 levels showed that the reaction undergoes a Pd(0) → Pd(II) → Pd(0) oxidation/reduction cycle, with the regioselective B(3)-H activation being the rate-determining step (RDS) for the full reaction profile. The computed RDS free energy barrier of 24.3 kcal mol-1 agrees well with the 82% yield of B(3,6)-diphenyl-o-carborane in ether solution at 298 K after 24 hours of reaction. The Ag2CO3 additive was shown to play a crucial role in lowering the RDS free energy barrier and facilitating the reaction. Natural charge population (NPA) and molecular surface electrostatic potential (ESP) analyses successfully predicted the experimentally observed regioselectivities, with electronic effects being revealed to be the dominant contributors to product selectivity. Steric hindrance was also shown to impact the reaction rate, as revealed by experimental and computational characterisation studies of substituents and ligand effects. Furthermore, computational predictions aligned with the experimental findings that NHC ligands outperform the phosphine ones for this particular reaction. Overall, the observed trends reported in this work are expected to assist in the rational optimisation of the efficiency and regioselectivity of this and related reactions.

6.
J Transl Med ; 21(1): 173, 2023 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-36870952

RESUMO

BACKGROUND: Clinically, Charcot-Marie-Tooth disease (CMT)-associated muscle atrophy still lacks effective treatment. Deletion and mutation of L-periaxin can be involved in CMT type 4F (CMT4F) by destroying the myelin sheath form, which may be related to the inhibitory role of Ezrin in the self-association of L-periaxin. However, it is still unknown whether L-periaxin and Ezrin are independently or interactively involved in the process of muscle atrophy by affecting the function of muscle satellite cells. METHOD: A gastrocnemius muscle atrophy model was prepared to mimic CMT4F and its associated muscle atrophy by mechanical clamping of the peroneal nerve. Differentiating C2C12 myoblast cells were treated with adenovirus-mediated overexpression or knockdown of Ezrin. Then, overexpression of L-periaxin and NFATc1/c2 or knockdown of L-periaxin and NFATc3/c4 mediated by adenovirus vectors were used to confirm their role in Ezrin-mediated myoblast differentiation, myotube formation and gastrocnemius muscle repair in a peroneal nerve injury model. RNA-seq, real-time PCR, immunofluorescence staining and Western blot were used in the above observation. RESULTS: For the first time, instantaneous L-periaxin expression was highest on the 6th day, while Ezrin expression peaked on the 4th day during myoblast differentiation/fusion in vitro. In vivo transduction of adenovirus vectors carrying Ezrin, but not Periaxin, into the gastrocnemius muscle in a peroneal nerve injury model increased the numbers of muscle myosin heavy chain (MyHC) I and II type myofibers, reducing muscle atrophy and fibrosis. Local muscle injection of overexpressed Ezrin combined with incubation of knockdown L-periaxin within the injured peroneal nerve or injection of knockdown L-periaxin into peroneal nerve-injured gastrocnemius muscle not only increased the number of muscle fibers but also recovered their size to a relatively normal level in vivo. Overexpression of Ezrin promoted myoblast differentiation/fusion, inducing increased MyHC-I+ and MyHC-II + muscle fiber specialization, and the specific effects could be enhanced by the addition of adenovirus vectors for knockdown of L-periaxin by shRNA. Overexpression of L-periaxin did not alter the inhibitory effects on myoblast differentiation and fusion mediated by knockdown of Ezrin by shRNA in vitro but decreased myotube length and size. Mechanistically, overexpressing Ezrin did not alter protein kinase A gamma catalytic subunit (PKA-γ cat), protein kinase A I alpha regulatory subunit (PKA reg Iα) or PKA reg Iß levels but increased PKA-α cat and PKA reg II α levels, leading to a decreased ratio of PKA reg I/II. The PKA inhibitor H-89 remarkably abolished the effects of overexpressing-Ezrin on increased myoblast differentiation/fusion. In contrast, knockdown of Ezrin by shRNA significantly delayed myoblast differentiation/fusion accompanied by an increased PKA reg I/II ratio, and the inhibitory effects could be eliminated by the PKA reg activator N6-Bz-cAMP. Meanwhile, overexpressing Ezrin enhanced type I muscle fiber specialization, accompanied by an increase in NFATc2/c3 levels and a decrease in NFATc1 levels. Furthermore, overexpressing NFATc2 or knocking down NFATc3 reversed the inhibitory effects of Ezrin knockdown on myoblast differentiation/fusion. CONCLUSIONS: The spatiotemporal pattern of Ezrin/Periaxin expression was involved in the control of myoblast differentiation/fusion, myotube length and size, and myofiber specialization, which was related to the activated PKA-NFAT-MEF2C signaling pathway, providing a novel L-Periaxin/Ezrin joint strategy for the treatment of muscle atrophy induced by nerve injury, especially in CMT4F.


Assuntos
Doença de Charcot-Marie-Tooth , Neuropatia Hereditária Motora e Sensorial , Humanos , Atrofia Muscular , Diferenciação Celular , Fibras Musculares Esqueléticas
7.
Sci Rep ; 13(1): 436, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624121

RESUMO

We aimed to explore whether superfluous sympathetic activity affects myoblast differentiation, fusion, and myofiber types using a continuous single-dose isoprenaline exposure model in vitro and to further confirm the role of distinct NFATs in ISO-mediated effects. Compared with delivery of single and interval single, continuous single-dose ISO most obviously diminished myotube size while postponing myoblast differentiation/fusion in a time- and dose-dependent pattern, accompanied by an apparent decrease in nuclear NFATc1/c2 levels and a slight increase in nuclear NFATc3/c4 levels. Overexpression of NFATc1 or NFATc2, particularly NFATc1, markedly abolished the inhibitory effects of ISO on myoblast differentiation/fusion, myotube size and Myh7 expression, which was attributed to a remarkable increase in the nuclear NFATc1/c2 levels and a reduction in the nuclear NFATc4 levels and the associated increase in the numbers of MyoG and MEF2C positive nuclei within more than 3 nuclei myotubes, especially in MEF2C. Moreover, knockdown of NFATc3 by shRNA did not alter the inhibitory effect of ISO on myoblast differentiation/fusion or myotube size but partially recovered the expression of Myh7, which was related to the slightly increased nuclear levels of NFATc1/c2, MyoG and MEF2C. Knockdown of NFATc4 by shRNA prominently increased the number of MyHC +, MyoG or MEF2C + myoblast cells with 1 ~ 2 nuclei, causing fewer numbers and smaller myotube sizes. However, NFATc4 knockdown further deteriorated the effects of ISO on myoblast fusion and myotube size, with more than 5 nuclei and Myh1/2/4 expression, which was associated with a decrease in nuclear NFATc2/c3 levels. Therefore, ISO inhibited myoblast differentiation/fusion and myotube size through the NFAT-MyoG-MEF2C signaling pathway.


Assuntos
Fibras Musculares Esqueléticas , Transdução de Sinais , Isoproterenol/farmacologia , Isoproterenol/metabolismo , Diferenciação Celular , Fibras Musculares Esqueléticas/metabolismo , Mioblastos/metabolismo , RNA Interferente Pequeno/metabolismo
8.
Inorg Chem ; 61(31): 12349-12355, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35877827

RESUMO

While a series of trinuclear rare-earth metal methylene (divalent >CH2) complexes with the so-called "ionic carbene" have been known for decades, the nature of metal-carbene interactions in this class of compounds remains elusive. Herein, a quantum chemical investigation has been performed to reveal the bonding nature in typical trimetallic "ionic carbene" species with the [M3(µ3-CH2)] (M = Sc, Y, La, and Ac) cluster core. Through various chemical bonding analyses, we have demonstrated that there exists a non-negligible covalent interaction between µ3-CH2 and M3 moieties, and the chemical bonding can be accounted for with two three-center two-electron (3c-2e) bonds. The chemical bonding analyses reveal that the metal d-electron configuration plays an important role in stabilizing various µ3-coordinated carbene complexes. The late transition metals do not favor such a µ3-coordination geometry, thus explaining why ionic carbene complexes are usually found for rare-earth and early transition metals. A series of ionic carbene complexes with early transition metals, lanthanides, and actinides are predicted to be stable as well. These reactive ionic carbene complexes may have characteristic properties for organic synthesis and catalysis.

9.
Anal Methods ; 14(4): 378-382, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35006230

RESUMO

Improved diagnostics are needed to manage the ongoing COVID-19 pandemic. In this study, we enhanced the color changes and sensitivity of colorimetric SARS-CoV-2 RT-LAMP assays based on triarylmethane dyes. We determined a mechanism for the color changes and obtained sensitivities of 10 RNA copies per microliter.


Assuntos
COVID-19 , SARS-CoV-2 , Colorimetria , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Pandemias , RNA Viral/genética , Reprodutibilidade dos Testes
10.
J Ethnopharmacol ; 284: 114782, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34728316

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Euonymus alatus (Thunb.) Siebold (family Celastraceae) is a deciduous woody shrub that is recorded in ShenNong BenCaoJing. It has been widely used for diabetes in traditional Chinese medicine. AIM OF THE STUDY: This study aimed to identify the most effective extract of Euonymus alatus (EA) against high glucose-induced endothelial cells in vitro, evaluate its pharmacological effect on retinopathy in diabetic mice and explore its underlying mechanism by RNA sequencing. METHODS: Retinal vascular endothelial cells (RF/6A) were treated with normal glucose (5.5 mmol/L glucose), high glucose (25 mmol/L glucose) or high glucose plus methanol extracts of EA (MEA), ethyl acetate extracts of EA (EEA) or water extracts of EA (WEA). The cytotoxicity and cell viability were determined by Cell Counting Kit-8 (CCK-8) assay. Cell migration was examined using the Transwell assay, and tube formation ability was measured using the Matrigel assay. Then, the KK-Ay mice were administered WEA or water for 12 weeks. The velocities of ocular blood flow were determined by Doppler ultrasound. RNA sequencing and reverse transcription quantitative PCR (RT-qPCR) were performed on WEA-stimulated RF/6A cells to reveal the underlying mechanism. RESULTS: The cytotoxicity assay found that 30 µg/mL MEA, 20 µg/mL EEA and 30 µg/mL WEA had no toxic effect on RF/6A cells. The cell viability results showed that MEA, EEA and WEA all decreased cell viability. Compared with the high-glucose group, both MEA and WEA decreased the number of migrated cells, while the inhibition rate of WEA was higher. The Matrigel results showed that 30 µg/mL WEA effectively reduced the total tube length. Moreover, WEA improved the haemodynamics of the central retinal artery. RNA sequencing coupled with RT-qPCR verified that WEA regulated angiogenesis-related factors in high glucose-stimulated RF/6A cells. CONCLUSIONS: WEA inhibits the migration and tube formation of RF/6A cells and improves diabetic retinopathy (DR) by mediating angiogenesis.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Euonymus/química , Fitoterapia , Animais , Glicemia/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Diabetes Mellitus , Medicamentos de Ervas Chinesas/química , Glucose/toxicidade , Haplorrinos , Masculino , Camundongos , Camundongos Endogâmicos A
11.
Front Cell Dev Biol ; 9: 759237, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926450

RESUMO

Satellite stem cell availability and high regenerative capacity have made them an ideal therapeutic approach for muscular dystrophies and neuromuscular diseases. Adult satellite stem cells remain in a quiescent state and become activated upon muscular injury. A series of molecular mechanisms succeed under the control of epigenetic regulation and various myogenic regulatory transcription factors myogenic regulatory factors, leading to their differentiation into skeletal muscles. The regulation of MRFs via various epigenetic factors, including DNA methylation, histone modification, and non-coding RNA, determine the fate of myogenesis. Furthermore, the development of histone deacetylation inhibitors (HDACi) has shown promising benefits in their use in clinical trials of muscular diseases. However, the complete application of using satellite stem cells in the clinic is still not achieved. While therapeutic advancements in the use of HDACi in clinical trials have emerged, histone methylation modulations and the long non-coding RNA (lncRNA) are still under study. A comprehensive understanding of these other significant epigenetic modulations is still incomplete. This review aims to discuss some of the current studies on these two significant epigenetic modulations, histone methylation and lncRNA, as potential epigenetic targets in skeletal muscle regeneration. Understanding the mechanisms that initiate myoblast differentiation from its proliferative state to generate new muscle fibres will provide valuable information to advance the field of regenerative medicine and stem cell transplant.

12.
J Am Chem Soc ; 143(31): 12261-12267, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34324334

RESUMO

The first linear silver supercluster based on icosahedral Ag13 units has been constructed via bridging of dpa ligands: Ag61(dpa)27(SbF6)4 (Hdpa = dipyridylamine) (Ag61). Single-crystal X-ray diffraction reveals that this rod-shaped cluster consists of four vertex-sharing Ag13 icosahedra in a linear arrangement. This Ag61 cluster represents the longest one-dimensional metal nanocluster with a resolved structure. Unprecedented electron coupling develops between their constituent Ag13 units. Theoretical studies disclose that the stabilities of the two superclusters are dictated by a strong interaction between the Ag13 units as well as the ligand effect of the dpa-Ag motifs. The quantum size effect accounts for the significant enhancement of the metal-related absorptions and the red shift at the near-infrared region as the length of the cluster increases. This work sheds light on the evolution of one-dimensional materials and an understanding of the electronic communication between the constituent clusters.

13.
Stem Cell Res Ther ; 12(1): 387, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34233723

RESUMO

AIMS: Neointimal hyperplasia remains a major obstacle in vascular regeneration. Sca-1-positive progenitor cells residing within the vascular adventitia play a crucial role in the assemblage of vascular smooth muscle cell (VSMC) and the formation of the intimal lesion. However, the underlying mechanisms during vascular injury are still unknown. METHODS AND RESULTS: Aneointimal formation rat model was prepared by carotid artery injury using 2F-Forgaty. After vascular injury, Meox1 expressions time-dependently increased during the neointima formation, with its levels concurrently increasing in the adventitia, media, and neointima. Meox1 was highly expressed in the adventitia on the first day after vascular injury compared to the expression levels in the media. Conversely, by the 14th day post-injury, Meox1 was extensively expressed more in the media and neointima than the adventitia. Analogous to the change of Meox1 in injured artery, Sca-1+ progenitor cells increased in the adventitia wall in a time-dependent manner and reached peak levels on the 7th day after injury. More importantly, this effect was abolished by Meox1 knockdown with shRNA. The enhanced expression of SDF-1α after vascular injury was associated with the markedly enhanced expression levels of Sca1+ progenitor cell, and these levels were relatively synchronously increased within neointima by the 7th day after vascular injury. These special effects were abolished by the knockdown of Meox1 with shRNA and inhibition of CXCR4 by its inhibitor, AMD3100. Finally, Meox1 concurrently regulated SDF-1α expressions in VSMC via activating CDC42, and CDC42 inhibition abolished these effects by its inhibitor, ZCL278. Also, Meox1 was involved in activation of the CXCR4 expression of Sca-1+ progenitor cells by CDC42. CONCLUSIONS: Spatio-temporal model of Meox1 expression regulates theSca-1+progenitor cell migration during the formation of the neointima through the synergistic effect of Rho/CDC42 and SDF-1α/CXCR4.


Assuntos
Proteínas de Homeodomínio/genética , Neointima , Células-Tronco , Fatores de Transcrição/genética , Animais , Lesões das Artérias Carótidas/genética , Movimento Celular , Células Cultivadas , Quimiocina CXCL12/genética , Miócitos de Músculo Liso , Ratos , Receptores CXCR4/genética , Proteína cdc42 de Ligação ao GTP
14.
Inorg Chem ; 59(13): 8864-8870, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32538629

RESUMO

Gold nanoclusters are attractive because of their electronic and optical properties. Many theoretical models have been proposed to explain their electronic structures through an electron-counting approach. However, subtle features may not be well explained by electron-counting rules. In this work, we have discovered a unique example of ligand-controlled skeletal bonding in two recently reported gold nanoclusters with very similar compositions and geometries. We have shown that the superatomic orbitals of the common kernel of the two clusters undergo different ligand-field splitting because of the different ligand-field strengths in the two clusters. Such a difference is clearly revealed by constructing the Jellium orbitals via an orbital alignment process, and a subsequent localization of the Jellium orbitals allows us to obtain localized bonding models. Finally, on the basis of localized bonding models, we predict the existence of a ligated gold cluster with a [Au32]4+ kernel.

15.
Zhongguo Zhong Yao Za Zhi ; 45(4): 746-754, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237474

RESUMO

The aim of this paper was to compare different effects of Tripterygium Glycosides Tablets from 6 different manufacturers on multiple organ injuries in rats and to explore mechanism of hepatotoxicity preliminarily from the perspective of apoptosis and oxidative stress. Rats were randomly divided into the groups normal, Zhejiang, Hunan, Hubei, Shanghai, Jiangsu and Fujian(7 groups with 16 rats in each group, sex in half). Rats were given Tripterygium Glycosides Tablets at 144 mg·kg~(-1)·d~(-1)(16 times the clinical equivalent dose) once a day according to its corresponding group like rats in Zhejiang group was given Tripterygium Glycosides Tablets from Zhejiang manufactures continuously for 20 days with the life and death situation of mice to be observed, then rats were executed to detect various indicators. RESULTS:: showed that 8 female rats in Zhejiang group died after 15 days of administration, the serum NEUT of rats in Hubei, Fujian and Shanghai groups was significantly lower than that of normal rats. The serum AST, ALT and/or TBiL levels were increased in all rats, and serum BUN and/or CRE levels of rats were also increased in Hunan, Hubei, Fujian and Shanghai groups. In dosage groups, testicular and ovarian coefficients of rats were reduced, the number of sperm were significant decreased while the rate of sperm malformation increased and sperm dynamics parameters of normal, especially in Jiangsu and Zhejiang groups. Liver histopathology and apoptosis of liver cells were observed in dosage groups, especially in Jiangsu and Hubei groups. In liver, Nrf2, HO-1 and Bcl-2 were inhibited and the protein expression level of Bax were increased simultaneously in dosage groups. These results showed that all Tripterygium Glycosides Tablets from 6 manufacturers could lead to chronic multiple organ injuries with disparate specialties in rats, and Jiangsu and Zhejiang groups were more toxic. It could be the mechanism promoting mitochondrial mediated Bax/Bcl-2 cell apoptosis signaling pathway and negatively regulating Nrf2/HO-1 oxidative stress signaling pathway that Tripterygium Glycosides Tablets from 6 different manufacturers resulted in chronic liver injury, the results above were for reference only in subsequent study.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Glicosídeos/farmacologia , Tripterygium/química , Animais , Apoptose , China , Feminino , Masculino , Estresse Oxidativo , Distribuição Aleatória , Ratos , Transdução de Sinais , Comprimidos
16.
Phys Chem Chem Phys ; 22(18): 10076-10086, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32342069

RESUMO

Due to the recent rise in the interest and research efforts on first-row transition metal catalysis and other radical-related reactions, open-shell systems play a much more important role in modern chemistry. However, the development of bonding analysis tools for open-shell systems is still lagging behind. In this work, we present the principal interacting spin orbital (PISO) analysis, which is an analysis framework developed based on our previously reported principal interacting orbital (PIO) analysis. We will demonstrate the power of our framework to analyse different kinds of open-shell systems, ranging from simple organic radicals to much more complicated coordination complexes, from which we can see how different kinds of odd-electron bonds could be identified. We will also illustrate its advantage when used in the analysis of chemical reactions, through which we can observe subtle patterns that could be helpful for tuning or rational design of related reactions.

17.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3494-3501, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602914

RESUMO

The aim of this paper was to compare the performance of acute liver injury in mice induced by Tripterygium Glycosides Tablets from 6 different manufacturers,and to explore the toxicity mechanism from the perspective of oxidative stress and apoptosis preliminarily. Male or female mice were randomly divided into normal group,Zhejiang group,Hunan group,Hubei group,Shanghai group,Jiangsu group and Fujian group. Mice in Tripgerygium Glycosides Tablets groups were given 16 times the clinical equivalent dose( 300 mg·kg-1) Tripgerygium Glycosides Tablets by oral administration for one time,mice were executed in 24 h after lavaged.Then the visceral brain coefficient of the organ was calculated. Histopathological changes of liver were observed by hematoxylin-eosin staining. Td T-mediated d UTP nick-end labeling was used to detect the apoptosis of the liver cells and the protein content of oxidative stress related factors in liver homogenate. Nuclear transcription factor E2-related factor( Nrf2) and heme oxygenase-1( HO-1) as well as mitochondrial mediated apoptosis-related protein expression levels of Bax and Bcl-2 in hepatic tissue were measured by Western blot.Within 24 hours of administration,6 male mice in Jiangsu group and 2 female mice in Zhejiang group were dying; compared with normal ones,liver coefficients of mice in Zhejiang,Shanghai,Jiangsu and Hunan groups were significantly increased,thymus coefficients in the first two groups were significantly reduced,as well as the lung coefficients of Fujian group mice,the rest was normal. In addition to Hubei group,serum AST,ALT or ALP levels of mice were increased,while TBi L were not being affected. Histopathological changes and apoptosis of liver cells were observed in all mice,and the degree of severity was ranked as Jiangsu,Zhejiang,Shanghai,Hunan,Hubei and Fujian group. All Tripterygium Glycosides Tablets increased the MDA and reduced the content of T-SOD,CAT or GSH in liver tissue while inhibited Nrf2,HO-1 and Bcl-2,increased the protein expression level of Bax( except Hunan group). Tripgerygium Glycosides Tablets from 6 manufacturers all resulted in liver function damage and liver histopathological changes,especially in Jiangsu,Hubei and Fujian,and the mechanism may related to inhibit Nrf2/HO-1 oxidative stress pathway and activate Bax/Bcl-2 apoptosis pathway to mediate lipid peroxidation and induce liver cell apoptosis. Triptolide A may be one of the main toxic components of Tripgerygium Glycosides Tablets that causing drug-induced liver injury. This study was conducted on normal mice with super dose medication,so the relevant results are for reference only.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Medicamentos de Ervas Chinesas/toxicidade , Glicosídeos/toxicidade , Tripterygium/toxicidade , Animais , Apoptose , Feminino , Heme Oxigenase-1/metabolismo , Peroxidação de Lipídeos , Fígado/efeitos dos fármacos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Distribuição Aleatória , Comprimidos , Proteína X Associada a bcl-2/metabolismo
18.
Dalton Trans ; 48(39): 14801-14807, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31552968

RESUMO

Systematic bonding analysis has been carried out for transition metal complexes containing more than one redox-active/non-innocent ligand. These complexes include tetralithio spiroaromatic palladole, dicupra[10]annulene, highly reduced nickel cyclooctadiene complex and tris(dithiolene)vanadium(iv). Our detailed bonding analysis reveals a common inter-ligand delocalisation pattern in these cases.

19.
Dalton Trans ; 48(40): 14962-14965, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31549712

RESUMO

The mononuclear cyclic (alkyl)(amino)carbene (cAAC) supported titanium(iii) chloride complex [(cAAC)2TiCl3] has been synthesized by treatment of free cAAC with TiCl3(THF)3. Further reduction of (cAAC)2TiCl3 with potassium graphite (KC8) afforded the desired (cAAC)2TiCl2 complex, which features a small S-T energy gap. Both complexes were structurally characterized and represent the first cAAC supported Ti complexes.

20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(4): 1071-1076, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418359

RESUMO

OBJECTIVE: To explore the relationship between the expression levels of JARID1B,Hes1 and MMP-9 genes and the stages of chronic myelogenous leukemia(CML) and the curative effect of imatinib mesylate (IM). METHODS: Peripheral blood samples of 15 cases of CML in chronic phase and 10 cases of CML in progressive phase were collected from the Hematology Department of Taihe Hospital affiliated to Hubei University of Medicine and 15 cases of healthy people in the Physical Examination Center. CML patients were divided into effective group and ineffective group based on the efficacy after treatment with IM, then real-time PCR was used to detect the expression levels of JARID1B, Hes1 and MMP-9 mRNA, finally, the differences in the level of gene expression and their correlations with CML stages and IM curative efficacy were analysed. RESULTS: The expression levels of Hes1 and MMP-9 in initially diagnosed patients in chronic and progressive phase without IM treatment were significantly higher than those of health people(P<0.05). There was no significant difference in the expression level of JARID1B between chronic phase patients and health people(P>0.05), but the expression level of JARID1B in the progressive phase patients was higher than that of health people (P<0.05). The expression levels of JARID1B and Hes1 in the IM-effective group were not significantly different from those in the IM-ineffective group (P=0.85,P=0.82), while the expression level of MMP-9 in the IM-effective group [JP2]was significantly lower than that in the IM-ineffective group(P<0.05). CONCLUSION: The expression levels of JARID1B Hes1 and MMP-9 relate with the different phase of CML; The expression levels of JARID1B and Hes1 have not significant relationship with IM curative efficacy, the MMP-9 gene expression level relates with IM curative efficacy.


Assuntos
Antineoplásicos/uso terapêutico , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Histona Desmetilases com o Domínio Jumonji , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Metaloproteinase 9 da Matriz , Proteínas Nucleares , Proteínas Repressoras , Fatores de Transcrição HES-1
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