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1.
Front Psychol ; 13: 938951, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783713

RESUMO

High-quality faculties are the fundamental guarantee to achieving the connotation development of higher education. Hence, performing university faculties determines the quality of teaching and the level of talent cultivation. Facing the change in teaching demand and environment, faculties need to change their working methods spontaneously to achieve high-level performance. Relevant empirical studies have shown that empowering leadership positively affects adaptive performance. However, some researchers have found that leadership effectiveness even has a negative effect. There may be two reasons for the inconsistency in the effectiveness of empowering leadership: (1) There is a lack of in-depth research on the effectiveness of empowering leadership and employees' performance in existing studies, and the exploration of its theoretical mechanism should be enriched. (2) The effectiveness of empowering leadership may be subject to the conditions of the individual's characteristics of the empowering. Therefore, the mechanism of empowering leadership on faculties' adaptive performance still needs to be further explored. This study explores the impact of empowering leadership on adaptive performance. Based on Social Exchange Theory and Psychology Empowerment theory, this study explores the mediating role of the leadership-member exchange relationship and psychological empowerment in the relationship between them. According to Regulatory Focus Theory, the moderating role of promotion focus and prevent focus was studied. We adopted questionnaire survey data including 292 individuals in Changchun, Shijiazhuang, and other cities; STATA 15 was conducted to test the hypotheses. The results showed that: (1) Empowering leadership was significantly and positively related to adaptive performance. (2) Leader-member exchange relationship and psychological empowerment play a mediating chain role in empowering leadership and adaptive performance; empowering leadership promotes psychology empowerment by enhancing the leadership-member exchange relationship, enhancing their adaptive performance. (3) Promotion focus positively regulates the relationship between psychological empowerment and adaptive performance. Individuals with a promotion focus have a significant positive impact on adaptive performance. Individuals with preventing focus do not weaken the positive impact of psychological empowerment on adaptive performance.

2.
Food Funct ; 13(12): 6749-6761, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35661847

RESUMO

Curculigo orchioides is widely used to treat osteoporosis in China. In this study, we identified the active substances in the crude polysaccharide (CO50) from C. orchioides that had anti-osteoporosis activity in vivo. Two polysaccharides, COP50-1 and COP50-4, were purified from CO50. Based on structural analysis, COP50-1 was composed of α-D-Glcp-(1→, ß-D-Galp-(1→, →4)-α-D-Glcp-(1→, →3,4)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→, →4,6)-ß-D-Manp-(1→, whereas COP50-4 was composed of α-L-Araf-(1→, →2)-α-L-Rhap-(1→, ß-D-Manp-(1→, α-D-Galp-(1→, →2,4)-α-L-Rhap-(1→, →2)-ß-D-Manp-(1→, →4)-α-D-GlcAp-(1→, →3)-α-D-GalAp-(1→, →4,6)-α-D-Galp-(1→, →2,3,6)-ß-D-Manp-(1→, →2,3,5)-α-L-Araf-(1→, →2,5)-α-L-Araf-(1→, →4)-α-D-Glcp-(1→ and →3)-α-D-Galp-(1→. Pharmacological assessment revealed that COP50-1 had no obvious osteogenic activity. However, COP50-4 (0.5 µM) significantly enhanced the differentiation and mineralization of osteoblasts in vitro. Moreover, the effect of COP50-4 was greater than that of 17ß-estradiol. Therefore, COP50-4 may be an effective component of CO50 that has great potential for development as an alternative drug for the treatment of osteoporosis.


Assuntos
Curculigo , Osteoporose , Curculigo/química , Humanos , Osteogênese , Osteoporose/tratamento farmacológico , Polissacarídeos/química , Rizoma/química
3.
J Chromatogr Sci ; 57(1): 9-16, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30084945

RESUMO

Retention time (RT) shifts are inevitable in liquid chromatography-mass spectrometry (LC-MS)-based metabolomics studies. RT alignment, aligning peaks originating from the same feature to an identical RT, is a necessary step prior to multivariate data analysis. Many RT alignment software packages and various algorithms have been developed. In the present study, a simple method for peak alignment was proposed using relative RT related to an inherent peak in the chromatogram, and its performance on RT alignment in untargeted metabolomics was evaluated using an LC-MS dataset acquired from plasma samples from osteoporotic rats, and compared with the common MarkerLynx XS method using different RT window. RT alignment accuracy and relative standard deviation (RSD) value of the intensity of 79 selected ions in a chromatogram were employed to assess the alignment effectiveness of Method I (0.2 RT window), Method II (0.5 RT window) and Method III (relative RT). The overall RT alignment accuracy of these three methods was 67.7%, 77.2% and 90.9%, and 44.3%, 72.2% and 82.3% of the ions had intensity RSD values <30%, respectively. The results demonstrated that Method III using relative RT significantly reduced the influence caused by RT shifts in LC-MS-based metabolomics. Furthermore, Method I and Method III were applied to discover plasma biomarkers for osteoporosis in rats. Thirteen and nineteen ions were selected as potential biomarkers, respectively. Among them, only eight common ions were found, which demonstrated that different sets of biomarkers were obtained using those two RT alignment methods. The relative RT method exhibited fewer missing values, a lower RSD of peak intensity and better performance in pattern recognition, thereby showing the great potential in future metabolomics studies.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Metabolômica/métodos , Algoritmos , Animais , Biomarcadores/sangue , Feminino , Análise dos Mínimos Quadrados , Metaboloma/fisiologia , Osteoporose/metabolismo , Ratos , Ratos Sprague-Dawley
4.
Carbohydr Polym ; 203: 292-301, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30318216

RESUMO

Curculigo orchioides, is a traditional Chinese medicine, is used in strengthening tendons and bones. We evaluated the anti-osteoporosis activity of the crude polysaccharide (CO70) isolated from the rhizomes of C. orchioides in ovariectomized rats. CO70 showed excellent anti-osteoporosis activity comparable to that of 17ß-estradiol. To explore the constituents responsible for the anti-osteoporosis activity of CO70, a novel homogeneous heteropolysaccharide, COP70-3, was isolated and purified from CO70. COP70-3 has a main backbone chain of (1→5)-linked α-L-Araf, (1,3→5)-linked α-L-Araf, (1→6)-linked ß-D-Galp, (1→4)-linked ß-D-Manp, (1,2→5)-linked α-L-Araf, (1→3)-linked ß-L-Rhap, (1, 3→6)-linked ß-D-Manp, (1→3)-linked α-D-GalpA, (1,3→6)-linked ß-D-Galp and (1→6)-linked α-D-Glcp residues. Furthermore, 1.87 nM COP70-3 obviously promoted the differentiation of MC3T3-E1 cells, while 0.94 and 1.87 nM COP70-3 significantly improved the osteogenic mineralization rate. These data indicate that COP70-3 has favorable anti-osteoporosis activity in vitro.


Assuntos
Curculigo/química , Osteoporose/tratamento farmacológico , Polissacarídeos/uso terapêutico , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Osso Esponjoso/efeitos dos fármacos , Osso Esponjoso/fisiopatologia , Sequência de Carboidratos , Diferenciação Celular/efeitos dos fármacos , Feminino , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Ratos Sprague-Dawley , Rizoma/química
5.
Int J Biol Macromol ; 112: 433-441, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29410058

RESUMO

Osteoporosis is a frequent disease among the elderly especially in postmenopausal women. Achyranthes bidentata is a traditional Chinese medicine used to strengthen bones. Here, A. bidentata polysaccharides (ABPs) were confirmed to have anti-osteoporosis effects. This study discovered biomarkers by comparing normal and osteoporosis rats and evaluated the effects of ABPs on osteoporosis based on the UPLC/Q-TOF-MS-based metabolomics analysis. We could then predict the underlying mechanisms from the perspective of metabolomics. Osteoporotic rats were treated with ABPs, and serum was then sampled for metabolic analysis. Glutarylcarnitine, lysoPC (18:1) and 9-cis-retinoic acid were identified as biomarkers. The ABPs could significantly increase these biomarkers, and this indicated that ABPs curing osteoporosis regulated lipid metabolism. The UPLC/Q-TOF-MS-based metabolomics analysis offered a potential strategy to evaluate the anti-osteoporosis effects of ABPs and to explain the relative mechanisms. Furthermore, the ABPs have good potential for treating osteoporosis.


Assuntos
Achyranthes/química , Biomarcadores/sangue , Osteoporose/tratamento farmacológico , Polissacarídeos/administração & dosagem , Alitretinoína , Animais , Carnitina/análogos & derivados , Carnitina/sangue , Ácidos Docosa-Hexaenoicos/sangue , Humanos , Lisofosfatidilcolinas/sangue , Metabolômica , Osteoporose/sangue , Osteoporose/metabolismo , Osteoporose/patologia , Ovariectomia , Polissacarídeos/química , Ratos , Tretinoína/sangue
6.
Carbohydr Polym ; 174: 48-56, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28821095

RESUMO

Osteoporosis is characterized by a reduction in bone mass and bone mineral density, which weakens the bone. Due to the side effects associated with drugs that are currently used to treat this disease, an increasing number of studies have focused on the research of effective ingredients derived from natural products. In particular, polysaccharides extracted from Chinese herbal medicines have received increasing attention. In this study, we isolated a homogeneous polysaccharide (COP90-1) from the dried rhizomes of Curculigo orchioides, a famous traditional Chinese medicine that is widely used in China, and determined its structure using the combined methods of chemical and spectral analyses. In addition, its effects on the proliferation and differentiation of primary mouse osteoblasts were assessed. The results showed that COP90-1 can effectively promote the proliferation and differentiation of primary osteoblasts in vitro. Additional studies are warranted to study the effects of this compound in vivo.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Curculigo/química , Medicamentos de Ervas Chinesas/farmacologia , Mananas/farmacologia , Rizoma/química , Animais , Conservadores da Densidade Óssea/química , Células Cultivadas , China , Medicamentos de Ervas Chinesas/química , Mananas/química , Camundongos , Osteoblastos/efeitos dos fármacos , Osteoporose
7.
Int J Biol Macromol ; 101: 543-552, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28347786

RESUMO

The objectives of this study were to evaluate the anti-diabetic and anti-hyperlipidemic effects and relative mechanisms of guava polysaccharides (GPs) in rats with type 2 diabetic mellitus (T2DM). The chemical characterization and monosaccharide compositions of GPs, named as GP-1, GP-2, GP-3, and GP-4, were determined by PMP-HPLC and FT-IR. The results revealed that all GPs had the typical saccharide absorptions, and all were heteropolysaccharides. In addition, GPs efficiently decreased levels of fasting blood glucose, glucosylated serum protein, serum insulin, homeostasis model assessment of insulin resistance, total cholesterol, triglyceride and serum alanine transaminase, improved oral glucose tolerance, and increased insulin sensitivity in rats with T2DM. Histopathological observations suggested that GP-1, GP-3, and GP-4 could alleviate injury in pancreatic islet cells, and Western blot analysis showed that these GPs upregulated gene expression of the insulin receptor, insulin receptor substrate 2, Akt, and glucose transporter type 4. Taken together, these data suggest that GPs may be beneficial in treating T2DM and reducing the risk of hyperlipidemia, vascular disease, and cirrhosis via the PI3K/Akt signaling pathway.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Polissacarídeos/farmacologia , Psidium/química , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/fisiopatologia , Jejum/sangue , Frutas/química , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Hipolipemiantes/química , Hipolipemiantes/uso terapêutico , Insulina/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/fisiopatologia , Masculino , Pâncreas/efeitos dos fármacos , Pâncreas/patologia , Polissacarídeos/química , Polissacarídeos/uso terapêutico , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
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