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1.
Geriatr Nurs ; 58: 352-360, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38878735

RESUMO

OBJECTIVES: There exists a deficiency in a distinct understanding of the intervention effects of Traditional Chinese Medicine (TCM) exercise therapies (Tai Chi, Yi Jin Jing, Ba Duan Jin, Liu Zi Jue, Qigong, Wu Qin Xi etc.) on cognitive function and its moderating variables in the elderly. This study aims to systematically evaluate the effects of TCM exercise therapies on the cognitive function of the elderly and further propose the best exercise intervention programme to delay the cognitive decline of the elderly. METHODS: PubMed, EBSCO host, Web of Science, EMbase, China National Knowledge Infrastructure and Wan Fang databases were searched for the effects of TCM exercise therapies on the cognitive function in older adults until July 2022. A meta-analysis of the included literature was performed using Stata 12.0 software, with a subgroup analysis of seven moderating variables: subject type, intervention content, intervention duration, intervention frequency, intervention period, study type and sample size. A random effects model was used to combine the overall effect sizes and to test for heterogeneity and publication bias across studies. RESULTS: A total of 20 publications with 1975 subjects were included. The TCM exercise therapies delayed cognitive decline in older adults (d = 0.83; 95 % CI [0.62-1.04]; P < 0.001). Subgroup analysis found that intervention content, intervention duration, intervention frequency, and intervention period were significant moderating variables influencing the effectiveness of the intervention. Among them, the Ba Duan Jin intervention (d = 0.85; 95 % CI [0.65-1.06]; P < 0.001), the duration of each exercise session of 60 min or more (d = 0.86; 95 % CI [0.71-1.00]; P < 0.001), the frequency of exercise of more than 5 times per week (d = 0.80; 95 % CI [0.64-0.96]; P < 0.001) and exercise cycles of 6-9 months (d = 0.96; 95 % CI [0.80-1.12]; P < 0.001) produced the largest effect sizes. CONCLUSION: TCM exercise therapies can effectively improve the cognitive function of the elderly. The best effect on the cognitive function of the elderly was achieved by choosing Ba Duan Jin and exercising at least five times a week for at least 60 min each time for a total of 6-9 months. The effect size of the TCM exercise therapy interventions on the cognitive function in older adults may be overestimated because of publication bias. In addition, large-sample, multicenter, high-quality randomised controlled trials should be conducted to validate this result.

2.
J Am Chem Soc ; 145(49): 26645-26656, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38051539

RESUMO

Photoactivatable luminescent materials have garnered enormous attention in the field of intelligent responsive materials, yet their design and applications remain challenging due to the limited variety of photoactivatable motifs. In the work described herein, we discovered a new photoactivatable luminescent motif that underwent ring-flipping isomerization under UV irradiation. The emission of this motif exhibited a rapid transformation from dark yellow to bright green, accompanied by a significant enhancement of quantum yield from 1.9% to 34.2%. Experimental and theoretical studies revealed that the effective intramolecular motion (EIM) was crucial to the distinct luminescence performance between two isomers. In addition, polymers containing this motif were achieved through a one-pot alkyne polymerization, exhibiting both photofluorochromic and photo-cross-linking properties. Furthermore, multiple types of photopatterning, including luminescent encryption, fluorescent grayscale imaging, and high-resolution photolithographic patterns, were realized. This work developed a new photoactivatable luminescent motif and demonstrated its potential applications in both small molecules and macromolecules, which will help in the future design of photoactivatable luminescent materials.

3.
Chemistry ; 29(56): e202301609, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37486704

RESUMO

We herein reported the design and synthesis of a ferrocene-based tetradentate ligand that is featured with modular synthesis and rigid skeleton. Its iron(II) complex facilitates asymmetric direct hydrogenation of ketones without the participation of extra strong-field ligand such as CO and isocyanide. Hydride donor lithium aluminum hydride (LAH) converted non-reactive Fe(II) species to reactive Fe(II) hydride species. With this catalyst, various chiral alcohols including the intermediate for montelukast could be prepared with satisfactory yields and enantioinduction.

4.
Angew Chem Int Ed Engl ; 60(9): 4619-4624, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33270973

RESUMO

The electrochemical three-component assembly of isoquinolines has been accomplished by ruthenaelectro-catalyzed C-H/N-H functionalization. The robustness of the electrocatalysis was reflected by an ample substrate scope, an efficient electrooxidation, and an operationally friendly procedure. The isolation of key intermediates and detailed mechanistic studies, including unprecedented cyclovoltammetric analysis of a seven-membered ruthenacycle, provided support for an unusual ruthenium(II/III/I) regime.

5.
Angew Chem Int Ed Engl ; 60(24): 13264-13270, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33651910

RESUMO

Rhodium-electrocatalyzed arene C-H oxygenation by weakly O-coordinating amides and ketones have been established by bimetallic electrocatalysis. Likewise, diverse dihydrooxazinones were selectively accessed by the judicious choice of current, enabling twofold C-H functionalization. Detailed mechanistic studies by experiment, mass spectroscopy and cyclovoltammetric analysis provided support for an unprecedented electrooxidation-induced C-H activation by a bimetallic rhodium catalysis manifold.

6.
Angew Chem Int Ed Engl ; 59(8): 3184-3189, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31777143

RESUMO

The catalytic generation of hypervalent iodine(III) reagents by anodic electrooxidation was orchestrated towards an unprecedented electrocatalytic C-H oxygenation of weakly coordinating aromatic amides and ketones. Thus, catalytic quantities of iodoarenes in concert with catalytic amounts of ruthenium(II) complexes set the stage for versatile C-H activations with ample scope and high functional group tolerance. Detailed mechanistic studies by experiment and computation substantiate the role of the iodoarene as the electrochemically relevant species towards C-H oxygenations with electricity as a sustainable oxidant and molecular hydrogen as the sole by-product. para-Selective C-H oxygenations likewise proved viable in the absence of directing groups.

7.
J Am Chem Soc ; 140(6): 2024-2027, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29377687

RESUMO

A ruthenium/C3-TunePhos catalytic system has been identified for highly efficient direct reductive amination of simple ketones. The strategy makes use of ammonium acetate as the amine source and H2 as the reductant and is a user-friendly and operatively simple access to industrially relevant primary amines. Excellent enantiocontrol (>90% ee for most cases) was achieved with a wide range of alkyl aryl ketones. The practicability of this methodology has been highlighted by scalable synthesis of key intermediates of three drug molecules. Moreover, an improved synthetic route to the optimal diphosphine ligand C3-TunePhos is also presented.

8.
Prostaglandins Other Lipid Mediat ; 134: 114-122, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917610

RESUMO

Docosahexaenoic acid (DHA) is an n-3 long chain polyunsaturated fatty acid (PUFA) that is involved in a wide range of cellular processes in human cells. Brain lipid binding protein (BLBP) exhibits a high affinity for n-3 PUFAs, especially DHA, but the precise functional contributions of DHA and BLBP in astrocytes are not clear. We analyzed cell viability and the ratio of Ki67 positive cells after manipulating DHA and/or BLBP levels in cultured astrocytes, and found that low-dose DHA stimulated proliferation of astrocytes, whereas this proliferative effect could be attenuated by downregulation of BLBP. Moreover, we found that astrocyte proliferation was directly regulated by BLBP independently of DHA. Taken together, low-dose DHA-induced astrocyte proliferation was disturbed by insufficient BLBP; and besides acting as a fatty acid transporter, BLBP was also involved in the proliferation of astrocytes directly.


Assuntos
Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Proteína 7 de Ligação a Ácidos Graxos/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Animais , Astrócitos/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ratos , Ratos Sprague-Dawley , Fase S/efeitos dos fármacos
9.
Chemistry ; 23(3): 546-548, 2017 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-27807893

RESUMO

A highly chemoselective and reactive direct catalytic reduction of various amides to amines and alcohols was developed by using a tetradentate ruthenium complex. The catalytic system showed excellent activity (turnover numbers up to 19 600) and great functional group tolerance under mild reaction conditions, compared to several bidentate and tridentate ruthenium-catalyzed systems.

10.
Nat Commun ; 14(1): 357, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36690612

RESUMO

Electricity-driven asymmetric catalysis is an emerging powerful tool in organic synthesis. However, asymmetric induction so far has mainly relied on forming strong bonds with a chiral catalyst. Asymmetry induced by weak interactions with a chiral catalyst in an electrochemical medium remains challenging due to compatibility issues related to solvent polarity, electrolyte interference, etc. Enabled by a properly designed phase-transfer strategy, here we have achieved two efficient electricity-driven catalytic asymmetric bromocyclization processes induced by weak ion-pairing interaction. The combined use of a phase-transfer catalyst and a chiral phosphate catalyst, together with NaBr as the bromine source, constitutes the key advantages over the conventional chemical oxidation approach. Synergy over multiple events, including anodic oxidation, ion exchange, phase transfer, asymmetric bromination, and inhibition of Br2 decomposition by NaHCO3, proved critical to the success.


Assuntos
Fosfatos , Estrutura Molecular , Ânions/química , Oxirredução , Catálise
11.
Am J Phys Med Rehabil ; 102(3): 229-234, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35944079

RESUMO

OBJECTIVE: The aim of the study is to re-evaluate the methodological quality and quality of evidence for a systematic evaluation/meta-analysis of the effect of mirror visual feedback therapy on physical function re-education after stroke. METHODS: Systematic evaluations/meta-analyses of mirror visual feedback therapy on physical function re-education after stroke were searched in the China Knowledge Network database, Wanfang database, Vipers database, China Biomedical Literature database, PubMed, Web of Science, and Embase using a computer, and the search time frame was up to January 2022. Methodological quality and quality of evidence ratings of the included studies were determined using the AMSTAR2 scale and GRADE classification by two authors. RESULTS: Seventeen publications were included. The evaluation with the AMSTAR2 scale showed that one study had an intermediate quality rating, five had a low-quality rating, and the remaining 11 were all very low quality. The GRADE scale showed 93 outcome indicators, of which 6 were intermediate, 23 were low grades, and the rest were very low grades, with low overall quality. CONCLUSIONS: Mirror visual feedback therapy is efficacious for physical function re-education after stroke and promotes recovery from physical dysfunction, but the methodological quality and quality of evidence from the related systematic evaluations/meta-analyses are low.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Retroalimentação Sensorial , Acidente Vascular Cerebral/terapia , China
12.
Micromachines (Basel) ; 13(6)2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35744549

RESUMO

Sodium-cooled reactors (SFR) have always been recognized as one of the most promising candidates for the fourth-generation nuclear systems as announced by the Generation-IV International Forum. In the design of SFR, helical wire-wrapped rod is applied to stabilize the structure of the rod bundle and enhance coolant mixing. Although there has been considerable research on SFR in computational fluid dynamics (CFD), the phenomenon of heat transfer has rarely been paid attention to. This article discovered that there exists reversed heat flux from coolant to wrapped wire, which is contrary to our usual understanding. This phenomenon has not been reported in previous CFD calculations. Hence, a solid heat conduction model is proposed to prove this phenomenon and analyze the heat transfer process. The simulation results show that the wrapping wire embedding depth, the shape of the calculation domain and the physical properties of all components have great influence on the magnitude of the reversed heat flux. The present findings will have strong influence on the temperature field and maximum value of the fuel rod as well as profound reference value for future flow calculation, especially in grid generation and treatment of the junction between the winding wire and fuel rod.

13.
Histochem Cell Biol ; 136(5): 515-26, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21928068

RESUMO

During the central nervous system (CNS) development, radial glia cells (RGCs) play at least two essential roles, they contribute to neuronal production and the subsequent guidance of neuronal migration, whereas its precise distribution and contribution to cerebral cortex remains less understood. In this research, we used Vimentin as an astroglial marker and Sox2 as a neural progenitor marker to identify and investigate RGCs in rat cerebral cortex at embryonic day (E) 16.5. We found that the Sox2+ progenitor cells localized in the germinal zone (GZ) of E16.5 cerebral cortex, ~95% Sox2+ cells co-localized with Vimentin+ or Nestin+ radial processes which extended to the pial surface across the cortical plate (CP). In vitro, we obtained RG-like cells from E16.5 cerebral cortex on adherent conditions, these Sox2+ Radial glia (RG)-like cells shared some properties with RGCs in vivo, and these Sox2+ RG-like cells could differentiate into astrocytes, oligodendrocytes and presented the radial glia-neuron lineage differentiation ability. Taken together, we identified and investigated some characterizations and properties of Sox2+ RGCs derived from E16.5 cerebral cortex, we suggested that the embryonic Sox2+ progenitor cells which located in the cortical GZ were mainly composed of Sox2+ RGCs, and the cortex-derived Sox2+ RG-like cells displayed the radial glia-neuron lineage differentiation ability as neuronal progenitors in vitro.


Assuntos
Córtex Cerebral/citologia , Embrião de Mamíferos/metabolismo , Células-Tronco Neurais/citologia , Neuroglia/citologia , Fatores de Transcrição SOXB1/metabolismo , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular , Células Cultivadas , Córtex Cerebral/embriologia , Embrião de Mamíferos/embriologia , Idade Gestacional , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas de Filamentos Intermediários/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Nestina , Células-Tronco Neurais/metabolismo , Neuroglia/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição SOXB1/genética , Vimentina/metabolismo
14.
Cell Biol Int ; 35(12): 1217-23, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21663595

RESUMO

Fetal brain tissue can be used in cell replacement therapy for PD (Parkinson's disease), but there is a poor donor supply of this tissue. NSCs (neural stem cells) may overcome this problem as they can be isolated and expanded in vitro. However, the usage of NSCs is limited because the differentiation of NSCs into specific dopaminergic neurons has proven difficult. In the present study, we investigated the effect of Nurr1 (nuclear receptor related factor 1), a transcription factor specific for the development and maintenance of the midbrain dopaminergic neurons on inducing the differentiation of NSCs into TH (tyrosine hydroxylase) immunoreactive dopaminergic neurons. Nonetheless, these cells exhibited an immature neuronal morphology with small cell bodies and short neurite processes, and they seldom expressed DAT (dopamine transporter), a late marker of mature dopaminergic neurons. However, forced co-expression of Nurr1 with Brn4, a member of the POU domain family of transcription factors, caused immature Nurr1-induced dopaminergic neurons to differentiate into morphologically and phenotypically more mature neurons. Thus the enriched generation of mature dopaminergic neurons by forced expression of Nurr1 with Brn4 may be of future importance in NSC-based cell replacement therapy for PD.


Assuntos
Diferenciação Celular , Neurônios Dopaminérgicos/citologia , Proteínas do Tecido Nervoso/genética , Células-Tronco Neurais/citologia , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Fatores do Domínio POU/genética , Transdução Genética , Animais , Neurônios Dopaminérgicos/metabolismo , Mesencéfalo/citologia , Mesencéfalo/metabolismo , Células-Tronco Neurais/metabolismo , Ratos , Ratos Sprague-Dawley
15.
Org Lett ; 23(3): 668-675, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33471538

RESUMO

A highly efficient catalytic system based on the cheap transition metal nickel for the asymmetric hydrogenation of challenging cyclic alkenyl sulfones, 3-substituted benzo[b]thiophene 1,1-dioxides, was first successfully developed. A series of hydrogenation products, chiral 2,3-dihydrobenzo[b]thiophene 1,1-dioxides, were obtained in high yields (95-99%) with excellent enantioselectivities (90-99% ee). According to the results of nonlinear effect studies, deuterium-labeling experiments, and DFT calculation investigations, a reasonable catalytic mechanism for this nickel-catalyzed asymmetric hydrogenation was provided, which displayed that the two added hydrogen atoms of the hydrogenation products could be from H2 through the insertion of Ni-H and subsequent hydrogenolysis.

16.
Cell Biol Int ; 34(9): 877-82, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20524937

RESUMO

NSCs (neural stem cells) provide a powerful research tool for the design and discovery of new approaches to cell replacement therapy during brain repair. However, the usefulness of this tool has been particularly obstructed by limited neuronal differentiation of NSCs. Brn-4, a member of the POU domain family of transcription factors, has been previously implicated in the development of neurons by expression analysis. Here, we directly investigated the effects of Brn-4 on the neuronal differentiation and development of NSCs derived from the E13 rat midbrain. We found that Brn-4 knockdown in NSCs resulted in a significant decrease of MAP-2-positive neurons with immature morphology. Overexpression of Brn-4 in NSCs markedly increased the production and maturation of newborn neurons. These results suggest that Brn-4 has a critical role in the neuronal differentiation of mesencephalic NSCs and the maturation of newborn neurons. Brn-4 may be utilized to manipulate NSCs for gene and cell therapy of several neurological diseases.


Assuntos
Diferenciação Celular , Mesencéfalo/citologia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Fatores do Domínio POU/metabolismo , Células-Tronco/citologia , Animais , Western Blotting , Células Clonais , Imunofluorescência , Proteínas Luminescentes/metabolismo , Interferência de RNA , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Células-Tronco/metabolismo , Transfecção
17.
Int J Neurosci ; 120(3): 192-200, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20374086

RESUMO

Neurogenesis in the hippocampus continues throughout adult life and can be regulated by the local microenvironment. To determine whether denervation stimulates neurogenesis in hippocampus, proliferation, migration, and differentiation of local neural stem cells (NSCs) in dentate gyrus was investigated after fimbria fornix transection. In the denervated hippocampus, NSCs proliferated markedly and migrated along the subgranular layer, and more newborn cells differentiated into neurons or astrocytes. After denervation, more newborn cells in the deafferented hippocampus expressed Brn-4 and differentiated into beta-Tubulin III positive neurons. It is concluded that the local NSCs in hippocampus may proliferate and migrate into granule cell layer, in which changes in the deafferented hippocampus provided a suitable microenvironment for hippocampal neurogenesis and the increased Brn-4 in denervated hippocampus may be involved in this process.


Assuntos
Células-Tronco Adultas/citologia , Movimento Celular , Proliferação de Células , Fórnice/lesões , Hipocampo/citologia , Neurogênese , Células-Tronco Adultas/metabolismo , Animais , Astrócitos/citologia , Feminino , Hipocampo/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Neurônios/citologia , Fatores do Domínio POU/biossíntese , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem , Tubulina (Proteína)/biossíntese
18.
Org Lett ; 22(18): 7230-7233, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32866391

RESUMO

The discrimination of a fluorine atom from a hydrogen atom has been challenging in asymmetric catalysis. We herein report iridium-catalyzed hydrogenation of α-fluoro ketones using a strategy of dynamic kinetic resolution. Both enantiomeric and diastereomeric selectivities were satisfactory in the preparation of ß-fluoro alcohols. The DFT calculation revealed a C-F···Na charge-dipole interaction in the transition state of hydride transfer. This noncovalent interaction would be responsible for the diastereomeric control.

19.
J Cancer ; 11(24): 7146-7156, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193877

RESUMO

Background: Circular RNAs (circRNAs), a novel class of endogenous noncoding RNAs, are involved in a variety of diseases, including several types of cancers. We hypothesized that circRNAs are involved in the tumorigenesis and development of clear cell renal cell carcinoma (ccRCC). Methods: To verify our hypothesis, we explored the circRNA expression profiles in 4 pairs of ccRCC tissues and their adjacent non-carcinoma tissues via microarray analysis. Selected circRNAs were further validated by qPCR. Moreover, hsa_circ_0005875 was selected for further study and the potential clinical values of hsa_circ_0005875 were investigated in 60 pairs of ccRCC tissues and adjacent normal controls. In addition, the role of hsa_circ_0005875 in ccRCC progression were performed using colony formation assay, Transwell assay and Martrigel-Transwell assay respectively. Finally, interactions between the circRNAs and miRNAs were predicted using Arraystar's miRNA target prediction software. Luciferase reporter assays were performed to evaluate the interaction between hsa_circ_0005875 and hsa_miR-145-5p. Results: The microarray data showed 1988 circRNAs were significantly dysregulated circRNAs, including 1033 upregulated and 955 downregulated ones in the ccRCC tissues. Hsa_circ_0005875 was confirmed to be significantly upregulated in the ccRCC tumor tissues and renal carcinoma cells. Further analysis revealed that hsa_circ_0005875 expression was associated with tumor size, pathological TNM stage, histological differentiation, and lymphatic metastasis. Functional experiments demonstrated that overexpression of hsa_circ_0005875 increased proliferation, migration and invasion abilities. Moreover, bioinformatics analysis and luciferase reporter assays suggest that hsa_circ_0005875 may serve as a ceRNA (competing endogenous RNA) of miR-145-5p to relieve the repressive effect of miR-145-5p on target ZEB2. Conclusions: These data indicate that hsa_circ_0005875 might play a role in promoting tumor growth and metastasis and be a potential biomarker of ccRCC.

20.
Chem Commun (Camb) ; 56(99): 15557-15560, 2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33244528

RESUMO

Chiral α-hydroxy-ß-lactams are key fragments of many bioactive compounds and antibiotics, and the development of efficient synthetic methods for these compounds is of great value. The highly enantioselective dynamic kinetic resolution (DKR) of α-keto-ß-lactams was realized via a novel proton shuttling strategy. A wide range of α-keto-ß-lactams were reduced efficiently and enantioselectively by Ni-catalyzed asymmetric hydrogenation, providing the corresponding α-hydroxy-ß-lactam derivatives with high yields and enantioselectivities (up to 92% yield, up to 94% ee). Deuterium-labelling experiments indicate that phenylphosphinic acid plays a pivotal role in the DKR of α-keto-ß-lactams by promoting the enolization process. The synthetic potential of this protocol was demonstrated by its application in the synthesis of a key intermediate of Taxol and (+)-epi-Cytoxazone.

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