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1.
Artigo em Inglês | MEDLINE | ID: mdl-35805502

RESUMO

Based on the Environmental Kuznets Curve (EKC) hypothesis, this paper examines whether rural broadband adoption affects agricultural carbon reduction efficiency (ACRE), using panel data from 30 Chinese provinces from 2011 to 2019. This paper achieves a measurement of ACRE by taking the carbon sink of agricultural as one of the desired outputs and using a Slacks-Based Measure (SBM) model and the global Malmquist-Luenberger (GML) index. The results show that: (1) Rural broadband adoption has a positive effect on ACRE. The relationship between the income of rural residents and ACRE was an inverted U-shaped, which confirms the EKC hypothesis. (2) Land transfer has a significant promoting effect on the relationship between rural broadband adoption and ACRE. When the land transfer rate is high, the positive effect of broadband adoption is obvious. (3) The positive effect of broadband adoption on ACRE was more obvious when farmers invested more in production equipment, that is to say, it has a significant positive moderating effect. As farmers in many developing countries suffer from increasingly frequent and severe extreme weather events, we believe that the results of this study also have implications for the implementation of agricultural carbon reduction and smart agricultural equipment roll-out in many countries.


Assuntos
Agricultura , Carbono , Carbono/análise , China , Desenvolvimento Econômico , Eficiência , Fazendeiros , Humanos
2.
J Agric Food Chem ; 70(7): 2231-2240, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35148079

RESUMO

Oleanane-type ginsenosides are highly biologically active substances in Panax ginseng, a popular Chinese dietary plant. Lack of key enzymes for glycosylation reactions has hindered de novo synthesis of these bioactive molecules. We mined candidate glycosyltransferases (GTs) of the ginseng database by combining key metabolites and transcriptome coexpression analyses and verified their function using in vitro enzymatic assays. The PgCSyGT1, a cellulose synthase-like GT rather than a UDP-dependent glucuronosyltransferase (UGT), was verified as the key enzyme for transferring a glucuronosyl moiety to the free C3-OH of oleanolic acid to synthesize calenduloside E. Two UGTs (PgUGT18 and PgUGT8) were first identified as, respectively, catalyzing the glycosylation reaction of the second sugar moiety of C3 and the C28 in the oleanane-type ginsenoside biosynthetic pathway. Then, we integrated these GTs in combinations into Saccharomyces cerevisiae genome and realized de novo biosynthesis of oleanane-type ginsenosides with a yield of 1.41 µg/L ginsenoside Ro in shake flasks. This report provides a basis for effective biosynthesis of diverse oleanane-type ginsenosides in microbial cell factories.


Assuntos
Ginsenosídeos , Ácido Oleanólico , Panax , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
3.
Eur J Pharmacol ; 857: 172449, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207208

RESUMO

Endoplasmic reticulum stress (ERS)-induced cardiomyocyte apoptosis plays an important role in the pathological process following myocardial infarction (MI). Macrophages that express microRNA-155 (miR-155) mediate cardiac inflammation, fibrosis, and hypertrophy. Therefore, we investigated if miR-155 regulates ERS-induced cardiomyocyte apoptosis after MI using a mouse model, lipopolysaccharide (LPS)-induced rat bone marrow derived macrophages (BMDMs)and hypoxia-induced neonatal rat cardiomyocytes (NRCMs). In vivo, miR-155 levelswere significantly higher in the MI group compared to the sham group. MI increasedmacrophage infiltration, nuclear factor-κB (NF-κB) activation, ERS induced-apoptosis, and SOCS1 expression, all of which were attenuated by the miR-155 antagomir, with the exception of SOCS1 expression. Additionally, post-MI cardiac dysfunction was significantly improved by miR-155 inhibition. In vitro, LPS upregulated miR-155 expression in BMDMs, and the miR-155 antagomir decreased LPS-induced macrophage inflammation and NF-κB pathway activation, but increased expression of SOCS1. Hypoxia increased NF-κB pathway activation, ERS marker expression, and apoptosis in NRCMs. Interestingly, conditioned medium from LPS-induced macrophages in combination with the miR-155 antagomir decreased, while the miR-155 agomir increased, the hypoxia-induced effects in NRCM's. The miR-155 agomir effects were reversed by inhibiting the NF-κB pathway in cardiomyocytes. Moreover, SOCS1 knockdown in LPS-induced macrophages promoted NF-κB pathway activation and ERS-induced cardiomyocyte apoptosis in the hypoxia-induced NRCMs, but the SOCS1-siRNA-induced effects were markedly decreased by miR-155 antagomir treatment. These data suggest that miR-155 inhibition attenuates ERS-induced cardiomyocyte apoptosis after MI via reducing macrophage inflammation through the SOCS1/NF-κB pathway.


Assuntos
Apoptose/genética , Estresse do Retículo Endoplasmático/genética , Macrófagos/metabolismo , MicroRNAs/antagonistas & inibidores , Miócitos Cardíacos/patologia , Animais , Antagomirs/farmacologia , Apoptose/efeitos dos fármacos , Células da Medula Óssea/citologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Coração/fisiopatologia , Inflamação/genética , Inflamação/patologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , MicroRNAs/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , NF-kappa B/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteína 1 Supressora da Sinalização de Citocina/genética
4.
Eur J Pharmacol ; 851: 122-132, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30721702

RESUMO

Inflammation plays an important role in sympathetic neural remodeling induced by myocardial infarction (MI). MiR-155 is a vital regulator of inflammatory responses, and macrophage-secreted miR-155 promotes cardiac fibrosis and hypertrophy. However, whether miR-155 influences MI-induced sympathetic neural remodeling is not clear. Therefore, we examined the role of miR-155 in MI-induced sympathetic neural remodeling and the related mechanisms in both an mouse model and in lipopolysaccharide (LPS)-stimulated bone marrow-derived macrophages (BMDMs). Our data showed that miR-155 expression was significantly enhanced in the myocardial tissues of MI mice compared to sham mice. Also, MI up-regulated the electrophysiological parameters, M1 macrophage polarization, inflammatory responses, and suppressor of cytokine signaling 1 (SOCS1) expression, which coincided with the increased expression of sympathetic nerve remodeling markers(nerve growth factor, tyrosine hydroxylase and growth-associated protein 43). Except for SOCS1, these proteins were attenuated by miR-155 antagomir. In vitro, LPS-stimulation promoted miR-155 expression in BMDMs. Consistent with the in vivo findings, miR-155 antagomir diminished the LPS-induced M1 macrophage polarization, nuclear factor (NF)-κB activation, and the expression of pro-inflammatory factors and nerve growth factor; but it increased the expression of SOCS1. Inversely, miR-155 agomir significantly potentiated LPS-induced pathophysiological effects in BMDMs. MiR-155 agomir-induced effects were reversed by the NF-κB inhibitor. Mechanistically, treatment with siRNA against SOCS1 augmented the aforementioned LPS-mediated activities, which were antagonized by the addition of miR-155 antagomir. In conclusion, miR-155 inhibition downregulated NGF expression via decreasing M1 macrophage polarization and inflammatory responses dependent on the SOCS1/NF-κB pathway, subsequently diminishing MI-induced sympathetic neural remodeling and ventricular arrhythmias (VAs).


Assuntos
Macrófagos/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Infarto do Miocárdio/patologia , Plasticidade Neuronal/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Animais , Antagomirs/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Inflamação/patologia , Inflamação/fisiopatologia , Macrófagos/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Fator de Crescimento Neural/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Sistema Nervoso Simpático/efeitos dos fármacos
5.
Food Funct ; 9(12): 6517-6525, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30474680

RESUMO

To enhance production of Antrodia cinnamomea triterpenoids (ACTs) from mycelia in solid-state culture, α-terpineol was added to the medium as an elicitor at an optimal concentration of 0.05 mL L-1. Multi-stage solvent extraction and HPLC analysis were performed, and the compositions of ACTs-E (from culture with elicitor) and ACTs-NE (from culture without elicitor) were found to be quite different. In assays of in vitro antitumor activity, ACTs-E, in comparison with ACTs-NE, produced stronger viability reduction in several tumor cell lines and stronger apoptosis induction in HeLa in a dose-dependent manner. Several related proteins involved in the mitochondrial pathway of apoptosis (p53, Bax, caspase-3) did not show expression upregulation by ACTs-E, suggesting that apoptosis induction occurred through a p53-independent process. Further analysis revealed that ACTs-E strongly inhibited synthesis of topoisomerase I (TOP1) and tyrosyl-DNA phosphodiesterase I (TDP1), which are involved in DNA repair, at both transcriptional and protein levels. Our findings suggest that ACTs-E have potential for applications in the pharmaceutical, clinical, and functional food industries, as a novel antitumor agent and a dual TOP1/TDP1 inhibitor.


Assuntos
Antineoplásicos Fitogênicos/biossíntese , Antrodia/metabolismo , Cicloexenos/metabolismo , Monoterpenos/metabolismo , Extratos Vegetais/antagonistas & inibidores , Triterpenos/metabolismo , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/farmacologia , Antrodia/química , Antrodia/crescimento & desenvolvimento , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Meios de Cultura/metabolismo , Monoterpenos Cicloexânicos , DNA Topoisomerases Tipo I/genética , DNA Topoisomerases Tipo I/metabolismo , Humanos , Micélio/química , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Triterpenos/análise , Triterpenos/farmacologia
6.
Zhonghua Yi Xue Za Zhi ; 93(11): 811-5, 2013 Mar 19.
Artigo em Chinês | MEDLINE | ID: mdl-23859384

RESUMO

OBJECTIVE: To evaluate the magnetic resonance diffusion-weighted imaging (DWI) in the detection of early ankylosing spondylitis and explore the manifestations of ankylosing spondylitis on whole body DWI (WB-DWI). METHODS: A total of 16 patients with early ankylosing spondylitis (AS) and 18 patients with low back pain (LBP) were recruited. Subchondral bone marrow apparent diffusion coefficient (ADC) in bilateral ilium and sacrum along sacroiliac joints were compared. An independent sample t-test (SPSS 16.0, SPSS, Chicago, III) was utilized to analyze the ADC value differences between groups. P < 0.05 denoted statistical significance. The mean ADC values of focal lesions in AS patients were also measured. Whole body diffusion weighted imaging was performed in additional 8 clinical confirmed AS patients and analyzed with the techniques of maximum intensity projection (MIP) and multiplanar reconstruction (MPR) in comparison with conventional MRI images to investigate the detectability of AS lesions with whole body DWI. RESULTS: Mean ADC values in 16 AS patients were (0.51 ± 0.13)×10(-3)mm(2)/s in ilium and (0.49 ± 0.17)×10(-3)mm(2)/s in sacrum. Mean ADC values in 18 LBP patients were (0.32 ± 0.06)×10(-3)mm(2)/s in ilium and (0.31 ± 0.08)×10(-3)mm(2)/s in sacrum. The ADC value in AS patients were statistically significantly greater than those in ilium and sacrum of LBP patients. Whole body DWI detected abnormalities in 8 AS patients within bilateral sacroiliac joints and other sites corresponding to the clinical symptoms of patients. The mean ADC values of focal lesions of this patient cohort were (1.31 ± 0.38)×10(-3)mm(2)/s in sacrum and (1.18 ± 0.27)×10(-3)mm(2)/s in ilium. CONCLUSION: Subchondral marrow ADC values along sacroiliac joints allow the differentiation of patients with early AS from LBP patients. In conjunctions with such post-processing techniques as MIP and MPR, WB-DWI allows a comprehensive assessment of AS patients to guide treatment, evaluate prognosis and follow therapeutic responses.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Espondilite Anquilosante/diagnóstico , Adolescente , Adulto , Feminino , Humanos , Dor Lombar/diagnóstico , Masculino , Imagem Corporal Total/métodos , Adulto Jovem
7.
Eur J Cardiothorac Surg ; 40(4): 939-47, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21334909

RESUMO

OBJECTIVE: To evaluate a new method for chest wall reconstruction using porcine-derived artificial rib and pleura in an animal experiment. Further, the clinical application was performed in five patients with large defects in the chest wall as a preliminary observation. METHODS: In animal experiments, a full-thickness chest wall defect of 7 cm × 8 cm was created in 12 adult mongrel dogs. Six dogs underwent reconstruction with porcine-derived artificial ribs and pleura (test group), and six with methylmethacrylate and double polyester mesh in the form of traditional Marlex sandwich technique (control group). At follow-up of each for 3, 6, and 12 months postoperatively, a general performance assessment and thoracic radiography were performed. Gross and histopathological examinations were carried out following humane euthanasia at the time of last follow-up. In clinical application, five patients with wide tumor resection in the chest wall underwent reconstruction with porcine-derived artificial ribs and pleura as well. RESULTS: In animal experiment, no perioperative death or hyperpyrexia occurred and no difference in either infection or dyspnea was noted between the two groups. Postoperative radiography revealed good thoracic integrity with no evidence of collapse, deformation, or abnormal movement in the test group. In the control group, similar results were observed, except that two dogs had abnormal movement in the chest wall associated with respiration. Severe adhesions between the 'sandwich' complex and the host tissues were identified in the control group, but by contrast, only mild adhesions were noted in the test group. The non-degradable polyester mesh induced fibrous proliferation and rejection, whereas the artificial pleura was absorbed with mild fibrous hyperplasia after 12 months. In clinical application, no thoracic deformity, chronic pain, or respiratory discomfort were observed at 1 or 12 postoperative months. CONCLUSIONS: Porcine-derived ribs and pleura can be employed safely to create an artificial chest wall to repair bony chest defects. The clinical results corresponded well with those of animal experiments, and thus confirmed the safety and feasibility of this new alternative of chest wall reconstruction. However, a long-term study in a large number is needed due to the small number of animals in this study.


Assuntos
Procedimentos de Cirurgia Plástica/métodos , Pleura/cirurgia , Próteses e Implantes , Costelas/cirurgia , Parede Torácica/cirurgia , Adolescente , Adulto , Idoso , Animais , Materiais Biocompatíveis , Bioprótese , Modelos Animais de Doenças , Cães , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pleura/patologia , Cuidados Pós-Operatórios/métodos , Radiografia , Procedimentos de Cirurgia Plástica/efeitos adversos , Costelas/patologia , Telas Cirúrgicas , Neoplasias Torácicas/cirurgia , Parede Torácica/diagnóstico por imagem , Coleta de Tecidos e Órgãos/métodos , Adulto Jovem
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