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1.
Org Lett ; 24(25): 4586-4591, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35714047

ABSTRACT

The intermolecular addition of allylic copper species generated from diene and copper hydride remains elusive. Herein copper hydride catalyzed asymmetric cross reductive coupling of conjugated dienes and ketoimines including trifluoromethyl ketoimines and α-iminoacetates was first achieved using chiral Ph-BPE as the ligand, providing rapid access to structurally and optically enriched homoallylic amines containing two vicinal stereogenic centers with up to 95% yield, 99% ee, and 11:1 diastereoselectivities.


Subject(s)
Copper , Polyenes , Amines , Catalysis , Stereoisomerism
2.
Ann Transl Med ; 10(5): 248, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35402592

ABSTRACT

Background: To evaluate the effects of four ceramic primers and two cement types on the bonding strength and durability between zirconia and resin cement. Methods: A total of 115 polished and air-abraded zirconia blocks were randomly divided into five groups (with 23 in each group) to test the performance of various primers. Meanwhile, all primer samples were divided into two subgroups randomly to measure the difference between the two cement types. Group No treat - Clearfil SA Cement (NT-C); group No treat - RelyX Unicem Cement (NT-U); group Z-Prime Plus - Clearfil SA Cement (ZPP-C); group Z-Prime Plus - RelyX Unicem Cement (ZPP-U); group Rely X Ceramic Primer - Clearfil SA Cement (RCP-C); group Rely X Ceramic Primer - RelyX Unicem Cement (RCP-U); group Clearfil Ceramic Primer - Clearfil SA Cement (CCP-C); group Clearfil Ceramic Primer - RelyX Unicem Cement (CCP-U); group Monobond-S - Clearfil SA Cement (MS-C); group Monobond-S - RelyX Unicem Cement (MS-U). According to the type of cement, the specimens were randomly selected for electron microscope scanning and energy spectrum analysis, and the tightness of zirconium porcelain resin adhesive interface was observed. The bonding strength of different adhesives and aging experiments were tested by shear test mode, and the shear strength of each experimental group was analyzed by one variable three factor analysis of variance. Results: All primers in the treated groups maintained a pristine structure without micro-crack, while the non-primer treatment sample exhibited obvious micro-cracks. Furthermore, among the four primers, the sample treated with Clearfil Ceramic Primer (CCP) obtained the highest bonding strength, with a statistically significant difference (P<0.05). However, cohesive failure mainly occurred in the CCP group before thermal cycles, and mixed failure occurred after thermal cycles. Conclusions: CCP is the superior primer, and can improve the bonding strength between zirconia and resin cement. Because the thermal cycles have a significantly adverse effect on the shear bond strength, CCP can be helpful in improving the durability of the zirconia bonding strength. Furthermore, the two cement types exhibited a similar bonding performance for zirconia.

3.
Mol Med Rep ; 16(2): 1269-1277, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28627590

ABSTRACT

In Parkinson's disease (PD), microglial activation-mediated neuroinflammation is associated with dopaminergic neurons degeneration in the substantia nigra pars compacta. Previous studies that have investigated this neurodegenerative disease have reported that the Sonic hedgehog (SHH) signaling pathway, through inhibiting the inflammatory processes, exerts a beneficial neuroprotective effect. However, the mechanisms underlying the anti­inflammatory and neuroprotective effects of this signaling pathway remain poorly understood. The present study aimed to further investigate these mechanisms in vitro and in vivo. At first, BV2 microglial cells treated with lipopolysaccharide (LPS) were used to induce an inflammatory response. It was observed that the activation of SHH signaling by Purmorphamine attenuated the LPS­induced inflammatory response, increased the expression of transforming growth factor­ß1 through the phosphatidylinositol 3­kinase (PI3K)/AKT serine/threonine kinase (Akt) intracellular signaling pathway and inhibited nuclear receptor subfamily 4 group A member 2, independently of the PI3K/Akt signaling pathway. Furthermore, the blockade of the PI3K/Akt signaling pathway by intranasal administration of LY294002, significantly reduced the SHH­associated neuroprotective effects on dopaminergic neurons, improved motor functions, and increased the microglial activation and inflammatory response in a mouse model of PD induced using 1­methyl­4­phenyl­1,2,3,6­tetrahydropyridine. In conclusion, the data of the present study reported that anti­inflammatory and neuroprotective effects can be obtained in BV2 microglial cells and in a mouse model of PD by successive activation of the SHH and PI3K/Akt signaling pathways.


Subject(s)
Dopaminergic Neurons/drug effects , Dopaminergic Neurons/metabolism , Hedgehog Proteins/metabolism , Morpholines/pharmacology , Phosphatidylinositol 3-Kinase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Purines/pharmacology , Signal Transduction/drug effects , Animals , Cell Line , Disease Models, Animal , Inflammation/metabolism , Male , Mice , Microglia/drug effects , Microglia/metabolism , Neuroprotective Agents/pharmacology , Parkinson Disease/drug therapy , Parkinson Disease/metabolism , Parkinson Disease/physiopathology
4.
Zhong Yao Cai ; 30(4): 401-3, 2007 Apr.
Article in Chinese | MEDLINE | ID: mdl-17674787

ABSTRACT

OBJECTIVE: To provide the scientific basis for identification and utilization of Memorialis hirta ( BL) Wedd. METHODS: Macroscopical identification and microscopic identification. RESULTS: To make system pharmacognostical studies on stalk and fine powder of Memorialis hirta (BL) Wedd. CONCLUSION: These characteristic can provide the scientific basis for identification of Memorialis hirta (BL) Wedd.


Subject(s)
Plant Stems/anatomy & histology , Plants, Medicinal/anatomy & histology , Urticaceae/anatomy & histology , Drugs, Chinese Herbal/isolation & purification , Pharmacognosy/methods , Plant Stems/cytology , Plants, Medicinal/cytology , Powders , Urticaceae/cytology
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