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1.
Food Funct ; 14(17): 7897-7911, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37491882

RESUMO

One of the top ten tonic herbs, Dangshen is frequently found in Chinese functional foods. With the inclusion of Dangshen in the list of food and medicine substances in 2020, the Dangshen Huangjiu (DHJ) emerged. In the Bencao, it is written that Huangjiu can "open up the curved veins and thicken the stomach and intestines". Furthermore, increasing investigations have verified the protective effect of Dangshen on the gastric mucosa. Therefore, we propose the hypothesis that the stomach mucosa might be protected by the DHJ. To demonstrate that the effect of solids in Dangshen Huangjiu (DHJG) on damaged human gastric mucosal epithelial cells (GES-1) was reversed, the study used ethanol to induce injury to GES-1 and then used protein immunoblotting (western blotting) to determine the expression levels of p-Akt, p-NF-κB-p65, and NF-κB-p65 proteins in the cells. 0.04 mol L-1 MNNG (5 mL kg-1 body weight) mixed with eating disorders(2 d satiety, l d starvation, 3 d cycle) was used to further establish a chronic non-atrophic gastritis (CNAG) model in Wistar rats, at the same time, the experimental rats were given DHJ and DHJG gavage. Cellular assays confirmed that DHJG (25-100 µg mL-1) dose-dependently increased the viability of ethanol-injured GES-1 and lowered p-Akt and p-NF-κB-p65/NF-κB-p65 protein expression. Animal experiments revealed that 10 mL kg-1 and 20 mL kg-1 DHJ had no significant effect on the basic activity and gastric tissues and related biochemical indices of healthy rats; DHJ (10 mL kg-1, 20 mL kg-1) and DHJG (2.8 g kg-1, 11.4 g kg-1) resulted in some improvement in weight loss and significant improvement in gastric mucosal pathology in CNAG rats with damage. Particularly, DHJ and DHJG significantly decreased the expression of p-Akt, p-NF-κB-p65/NF-κB-p65 and Bcl-2/Bax proteins and Akt, IKKß, IκBα and NF-κB mRNA in the gastric tissues of CNAG rats. These results showed that DHJG ameliorates ethanol-induced GES-1 cell injury; both DHJ and DHJG alleviate CNAG, and the mechanisms by which they do so may be related to DHJ and DHJG increasing the antioxidant capacity (elevating SOD, decreasing MDA), attenuating inflammatory responses (decreasing IL-1ß, IL-6, and TNF-α), reversing apoptosis (reducing the Bcl-2/Bax ratio) and down-regulating gastric tissue p-Akt and p-NF-κB-p65/NF-κB-p65 protein expression as well as Akt, IKKß, IκBα and NF-κB mRNA expression. This study indicates that the interventional effects of DHJ and DHJG in CNAG may act through the Akt/NF-κB signaling pathway.


Assuntos
Codonopsis , Medicamentos de Ervas Chinesas , Gastrite , Gastrite/tratamento farmacológico , Humanos , Codonopsis/química , Inflamação/tratamento farmacológico , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Ratos , Ratos Wistar , Linhagem Celular , Etanol , Sobrevivência Celular/efeitos dos fármacos , Apoptose
2.
Polymers (Basel) ; 14(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35267811

RESUMO

End concrete cover separation is one of the most common failure modes for RC beams strengthened with external FRP reinforcement. The premature failure mode significantly restricts the application of FRP materials and could incur serious safety problems. In this paper, an innovative stress field-based analytical approach is proposed to assess the failure strength of end concrete cover separation and the conventional plane-section analysis is extended to evaluate the corresponding carrying capacity of FRP-strengthened RC beams. First, the dowel action of reinforcement and the induced concrete splitting, reflecting the interaction between concrete, steel and FRP, are considered in establishing the geometrical relationships of stress field for cracked concrete block. Then, the cracking angle and innovative failure criterion, considering the arrangement of steel and FRP reinforcement and cracking status of concrete and its softening effect, are derived to predict the occurrence of concrete cover separation and related mixed modes of debonding failure. Subsequently, an extended sectional analytical approach, in which the components of effective tensile strain of FRP resulted from flexural and shear actions are both considered, is presented to evaluate the carrying capacity of strengthened beams. Finally, the proposed calculational model is effectively validated by experimental results available in the literature.

3.
Materials (Basel) ; 14(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34771924

RESUMO

Through proper arranging of a hybrid combination of longitudinal fiber reinforced polymer (FRP) bars and steel bars in the tensile region of the beam, the advantages of both FRP and steel materials can be sufficiently exploited to enhance the flexural capacity and ductility of a concrete beam. In this paper, a methodology for the flexural strength design of hybrid FRP-steel reinforced concrete (RC) beams is proposed. Firstly, based on the mechanical features of reinforcement and concrete and according to the latest codified provisions of longitudinal reinforcement conditions to ensure ductility level, the design-oriented allowable ranges of reinforcement ratio corresponding to three common flexural failure modes are specified. Subsequently, the calculation approach of nominal flexural strength of hybrid FRP-steel RC beams is established following the fundamental principles of equilibrium and compatibility. In addition to the common moderately-reinforced beams, the proposed general calculation approach is also applicable to lightly-reinforced beams and heavily-reinforced beams, which are widely used but rarely studied. Furthermore, the calculation process is properly simplified and the calculation accuracy is validated by the experimental results of hybrid FRP-steel RC beams in the literature. Finally, with the ductility analysis, a novel strength reduction factor represented by net tensile steel strain and reinforcement ratio is proposed for hybrid FRP-steel RC beams.

4.
Immunol Invest ; 50(5): 461-477, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32552226

RESUMO

BACKGROUND: Inflammatory and inducible chemokines are the hallmarks of malignancy. Monocyte chemo-attractant protein-1 (MCP-1) is a crucial chemokine implicated in infection and inflammation. Methods: We performed an updated meta-analysis of thirty independent case-control studies with 6,777 cancer cases and 7,840 controls to determine if the MCP-1 gene rs1024611 A > G variant is associated with the risk of cancer. Results: The G allele carriers of rs1024611 in the MCP-1 gene might have a null association with cancer risk in overall comparison. In a subgroup analysis by ethnicity, we identified a marked association between the MCP-1 G allele rs1024611 polymorphism and cancer risk in the Caucasian populations (GG vs. AA: OR = 1.72, 95% CI, 1.12-2.64, P = .013, and GG vs. AG/AA: OR = 1.82, 95% CI, 1.19-2.78, P = .006). The potential bias in literature selection was witnessed in this meta-analysis (G vs. A: P Begg's = â€Š0.187, PEgger's = â€Š0.049; and GG/GA vs. AA: P Begg's = â€Š0.069, PEgger's = â€Š0.024). The adjusted ORs and CIs of the nonparametric "trim-and-fill" method demonstrated the reliability of these findings. The outcome of heterogeneity analysis indicated that heterogeneity might be due to small sample sizes (<1000 subjects), cancer types (bladder cancer, other cancers), ethnicity (Asians), and population-based studies. However, the sensitivity analysis validated the reliability of the findings. Conclusion: In conclusion, this updated meta-analysis showed that the G carrier of the MCP-1 gene rs1024611 is associated with susceptibility to cancer in Caucasian.


Assuntos
Quimiocina CCL2/genética , Neoplasias/genética , Grupos Populacionais , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Risco
5.
Behav Brain Res ; 288: 39-49, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25882722

RESUMO

Post-traumatic stress disorder (PTSD) is a stress-related mental disorder caused by traumatic experiences. Studies have found that exposure to early stressful events is a risk factor for developing PTSD. However, a limited number of studies have explored the effects of traumatic stress in early adolescence on behavior, hypothalamic-pituitary-adrenal (HPA) axis function, central corticotropin releasing factor receptor 1 (CRFR1) expression and the relative vulnerability of PTSD in adulthood. The current study aims to explore these issues using inescapable electric foot shock to induce a PTSD model in early adolescent rats. Meanwhile, running on a treadmill for six weeks and administration of the antagonist with 3.2mg/kg/day of CP-154, 526 for 14 consecutive days were used as therapeutic measures. Presently, the stress (S) group showed more anxiety and depression in the open field (OF) test and elevated plus maze (EPM) test, memory damage in the Y maze test, decreased basal CORT level, increased DEX negative feedback inhibition and exacerbated and longer-lasting reaction to CRH challenge in the DEX/CRH test compared with the control group. Central CRFR1 expression was also changed in the S group, as evidenced by the increased CRFR1 expression in the hypothalamus, amygdala and the prefrontal cortex (PFC). However, treadmill exercise alleviated early adolescent stress-induced behavior abnormalities and improved the functional state of the HPA axis, performing a more powerful effect than the CRFR1 antagonist CP-154, 526. Additionally, this study revealed that the alteration of central CRFR1 expression might play an important role in etiology of PTSD in adulthood.


Assuntos
Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Transtornos de Estresse Pós-Traumáticos/metabolismo , Animais , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Corticosterona/metabolismo , Depressão/tratamento farmacológico , Depressão/metabolismo , Modelos Animais de Doenças , Eletrochoque , Terapia por Exercício/métodos , , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/crescimento & desenvolvimento , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/crescimento & desenvolvimento , Pirimidinas/farmacologia , Pirróis/farmacologia , Distribuição Aleatória , Ratos Wistar , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Corrida , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/terapia , Estresse Psicológico/metabolismo
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