Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Front Plant Sci ; 14: 1331704, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38146272

RESUMO

Introduction: Limited water and soil phosphorus (P) availability often hampers lucerne productivity in semiarid regions. Plastic film mulch and P application typically enhance young lucerne (2-3 years) productivity by increasing soil water use and P availability. However, the prolonged impact of film mulch and P application on lucerne productivity as the stand ages remains unclear. Methods: This study conducted a 9-year field experiment on the semiarid Loess Plateau to investigate how film mulch and P application affect lucerne forage yield, soil water content, and soil fertility. The field experiment used a split-plot design with randomized blocks, in which the whole plots were with (M1) and without plastic film mulch (M0), and the split plots were four P rates (0 (P0), 9.7 (P1), 19.2 (P2), and 28.8 (P3) kg P ha-1). Results and discussion: The M1 treatment produced significantly higher lucerne forage yields than the M0 treatment during the first five years, but the yield-increasing effect of film mulch gradually diminished over time, with no effect in Years 6-8, and lower yields than the M0 treatment in Year 9. Phosphorus fertilization significantly increased forage yield after Year 3 in the M0 treatment, but only in Years 3-5 in the M1 treatment. In Years 2-5, film mulch significantly increased soil organic carbon, total nitrogen (N), inorganic N, and microbial biomass carbon in P0, P1, and P2 but not in P3. However, in Years 7-9, film mulch significantly decreased soil available potassium (K), organic carbon mineralization, lucerne density, and shoot K concentration, but did not reduce soil N and P availability at any level P of application. Moreover, plastic film mulch significantly increased the soil water content at 0-300 cm deep from Year 7 onwards. In conclusion, film mulch ceased to enhance lucerne production beyond year 6, which could not be attributed to soil water content, N or P availability but was partially associated with reduced soil K availability. Consequently, future research should focus on soil K availability, and K addition should be considered after five years in lucerne pastures mulched with plastic film in semiarid areas.

2.
BMC Complement Med Ther ; 23(1): 197, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322476

RESUMO

BACKGROUND: The dried bark of Ailanthus altissima (Mill.) Swingle is widely used in traditional Chinese medicine for the treatment of ulcerative colitis. The objective of this study was to explore the therapeutic basis of the dried bark of Ailanthus altissima (Mill.) Swingle for the treatment of ulcerative colitis based on Virtual Screening-Molecular Docking-Activity Evaluation technology. METHODS: By searching the Traditional Chinese Medicine Systems Pharmacology TCMSP Database and Analysis Platform, 89 compounds were obtained from the chemical components of the dried bark of Ailanthus altissima (Mill.) Swingle. Then, after preliminarily screening the compounds based on Lipinski's rule of five and other relevant conditions, the AutoDock Vina molecular docking software was used to evaluate the affinity of the compounds to ulcerative colitis-related target proteins and their binding modes through use of the scoring function to identify the best candidate compounds. Further verification of the compound's properties was achieved through in vitro experiments. RESULTS: Twenty-two compounds obtained from the secondary screening were molecularly docked with ulcerative colitis-related target proteins (IL-1R, TLR, EGFR, TGFR, and Wnt) using AutoDock Vina. The free energies of the highest scoring compounds binding to the active cavity of human IL-1R, TLR, EGFR, TGFR, and Wnt proteins were - 8.7, - 8.0, - 9.2, - 7.7, and - 8.5 kcal/mol, respectively. The potential compounds, dehydrocrebanine, ailanthone, and kaempferol, were obtained through scoring function and docking mode analysis. Furthermore, the potential compound ailanthone (1, 3, and 10 µM) was found to have no significant effect on cell proliferation, though at 10 µM it reduced the level of pro-inflammatory factors caused by lipopolysaccharide. CONCLUSION: Among the active components of the dried bark of Ailanthus altissima (Mill.) Swingle, ailanthone plays a major role in its anti-inflammatory properties. The present study shows that ailanthone has advantages in cell proliferation and in inhibiting of inflammation, but further animal research is needed to confirm its pharmaceutical potential.


Assuntos
Ailanthus , Colite Ulcerativa , Humanos , Animais , Ailanthus/química , Simulação de Acoplamento Molecular , Colite Ulcerativa/tratamento farmacológico , Casca de Planta/química , Receptores ErbB
3.
J Biomed Nanotechnol ; 18(1): 120-131, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35180905

RESUMO

As one of the most challenging inflammatory diseases, the incidence of ulcerative colitis (UC) is increasing year by year, but the existing therapeutic drugs are not effective and lack of targeting. Nanomaterials are expected to become promising delivery system due to their good targeting effects. Here, we designed a nanomaterial sensitive to reactive oxygen species, which can be used to treat IBD, especially UC. It is a self-assembled polyether micelle that can be oxidized at the inflammation site where the concentration of reactive oxygen increases, and effectively release the encapsulated budesonide (Bud). Experiments have proved that for DSS-induced colitis, the synthetic drug-loaded nanoparticles have excellent therapeutic effects, can effectively repair intestinal barrier, and significantly improve the damaged colon tissue. At the same time, it has a beneficial regulatory effect on inflammatory factors. Molecular mechanism studies have shown that it achieves its therapeutic effects by activating the peroxisome proliferators-activated receptors-γ (PPAR-γ) pathway and inhibiting the nuclear factor (NF)-κB pathway. This study proves that oral nano-micelles have an important impact on improving the efficacy of UC treatment drugs and have far-reaching significance for the targeted treatment of gastrointestinal diseases.


Assuntos
Colite Ulcerativa , Nanoestruturas , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colo/metabolismo , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Micelas , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio
4.
Zhonghua Nan Ke Xue ; 24(12): 1116-1121, 2018 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-32212493

RESUMO

OBJECTIVE: To investigate the effect of Ruyi Jinhuang Plaster (RJP) on testosterone propionate-induced BPH in the rat model and its action mechanisms. METHODS: Forty-eight SD male rats were randomly divided into six groups of equal number: normal control, BPH model control, finasteride, and high-, medium- and low-dose RJP. The BPH model was made in the latter five groups by hypodermic injection of testosterone propionate. From the first day of modeling, the rats of the normal control and BPH model control groups were treated with blank plasters and those of the high-, medium- and low-dose RJP groups with RJPs at 42.0, 21.0 and 10.5 cm2/kg applied to the dehaired area of the back, and those of the finasteride group by gavage of finasteride at 4.5 mg/kg, all once a day for 30 successive days. Then the prostates of the animals were harvested for observation of histopathological changes by HE staining, measurement of the areas of interstitial and epithelial cells and prostatic glandular cavity, and determination of the expressions of P38, JNK2, NF-кBP65 and STAT3 proteins in the prostate tissue by Western blot. RESULTS: Compared with the BPH model controls, the high-dose RJP group showed significantly decreased proliferation and area proportion of prostatic epithelial cells (P < 0.05), increased area proportion of the prostatic glandular cavity (P < 0.05), and reduced expressions of P38, p-P38, NF-кBP65, P-NF-кBP65, STAT3, P-STAT3 and JNK2 in the prostate tissue (P < 0.05); the medium-dose RJP group exhibited markedly down-regulated expressions of JNK2 and NF-кBP65 (P < 0.05) but an up-regulated level of p-JNK (P < 0.05); while the low-dose RJP group displayed a remarkably reduced expression of JNK2 (P < 0.05) but an elevated level of p-JNK (P < 0.05). CONCLUSIONS: RJP suppresses BPH in the model rat by down-regulating the expressions of P38, p-P38, NF-кBP65, P-NF-кBP65, STAT3, P-STAT3 and JNK2 or up-regulating that of p-JNK in the prostate tissue.


Assuntos
Medicamentos de Ervas Chinesas , Extratos Vegetais , Hiperplasia Prostática , Propionato de Testosterona , Animais , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Finasterida , Masculino , Proteína Quinase 9 Ativada por Mitógeno/efeitos dos fármacos , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/metabolismo , Ratos , Fator de Transcrição STAT3/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Testosterona , Proteínas Quinases p38 Ativadas por Mitógeno
5.
Mol Med Rep ; 15(6): 3803-3809, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28393248

RESUMO

Hyperglycemia is a typical pathogenic factor in a series of complications among patients with type II diabetes. Epigallocatechin-3-gallate (EGCG) is the major polyphenol extracted from green tea and is reported to be an antioxidant. The aim of the present study was to examine the effect of EGCG on insulin resistance in human HepG2 cells pretreated with high concentrations of glucose. The protein kinase B (AKT)/glycogen synthase kinase (GSK) pathways were analyzed using western blot analysis in HepG2 cells and primary mouse hepatocytes treated with high glucose and/or EGCG. Cellular glycogen content was determined using a glycogen assay kit. Reactive oxygen species (ROS) production was determined using dihydroethidium staining and flow cytometry. c­JUN N­terminal kinase (JNK)/insulin receptor substrate 1 (IRS1)/AKT/GSK signaling was explored using western blot analysis in HepG2 cells treated with high glucose and/or EGCG or N-acetyl-cysteine. High glucose significantly decreased the levels of phosphorylated AKT and GSK in HepG2 cells and mouse primary hepatocytes. Pretreatment with EGCG significantly restored the activation of AKT and GSK in HepG2 cells and primary hepatocytes exposed to high glucose. In HepG2 cells and primary hepatocytes, glycogen synthesis was improved by EGCG treatment in a dose­dependent manner. High glucose significantly stimulated the production of ROS while EGCG protected high glucose­induced ROS production. ROS is known to serve a major role in high glucose induced­insulin resistance by increasing JNK and IRS1 serine phosphorylation. In the present study, EGCG was observed to enhance the insulin­signaling pathway. EGCG ameliorated high glucose­induced insulin resistance in the hepatocytes by potentially decreasing ROS­induced JNK/IRS1/AKT/GSK signaling.


Assuntos
Catequina/análogos & derivados , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Resistência à Insulina , Animais , Catequina/farmacologia , Linhagem Celular Tumoral , Glucose/metabolismo , Glicogênio/metabolismo , Células Hep G2 , Humanos , Insulina/metabolismo , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
6.
Pharmacol Biochem Behav ; 116: 25-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24125782

RESUMO

Drug combination is frequently used in pain treatment, which can produce similar analgesia with reduced dosage and side effects. In the present study, we examined the effects of co-administration of propofol, a general anesthetic, and alfentanil, an opioid analgesic drug, and the types of interactions between them in heat induced acute phasic and acetic-acid induced acute tonic pain models using the up-and-down method. In both pain models, alfentanil was administered in fixed-dose fractions of the 50% effective dose (ED50), and the types of interactions were determined by isobolographic analysis. In hot plate test, alfentanil (35.6-50.0 µg/kg, i.v.), propofol (6.5-15.5mg/kg, i.v.), and their combinations (80%, 50%, 30% and 10% of a single drug ED50) produce a significant, dose-dependent antinociception. In the tail-flick test, alfentanil (35.6-50.0 µg/kg, i.v.), propofol (5.0-14.3mg/kg, i.v.), and their combination significantly and dose dependently extend the tail-flick latency. In the acetic-acid induced writhing test, alfentanil (12.5-23.2 µg/kg, i.p.), propofol (15.0-28.5mg/kg, i.p.), and their combination significantly and dose dependently reduce the frequency of writhing. In all the above pain models, isobolographic analysis revealed a significant synergistic interaction between alfentanil and propofol, with about 4-fold reduction of doses of both drugs, in comparison with each single drug's ED50. These data suggest that the combination of alfentanil and propofol synergistically suppresses acute phasic and tonic pain in mice, indicating a potential application in pain treatment.


Assuntos
Alfentanil/farmacologia , Analgésicos/farmacologia , Propofol/farmacologia , Alfentanil/administração & dosagem , Animais , Quimioterapia Combinada , Camundongos , Propofol/administração & dosagem
7.
Int J Mol Sci ; 14(8): 15655-68, 2013 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-23896596

RESUMO

Tamoxifen resistance remains to be a huge obstacle in the treatment of hormone-dependent breast cancer, and this therefore highlights the dire need to explore the underlying mechanisms. The epithelial-mesenchymal transition (EMT) is a molecular process through which an epithelial cell transfers into a mesenchymal phenotype. Roles of EMT in embryo development, cancer invasion and metastasis have been extensively reported. Herein, we established tamoxifen-resistant MCF-7/TR breast cancer cells and showed that MCF-7/TR cells underwent EMT driven by enhanced endogenous TGF-ß/Smad signaling. Ectopic supplement of TGF-ß promoted in MCF-7 cells a mesenchymal and resistant phenotype. In parallel, we demonstrated that resveratrol was capable of synergizing with tamoxifen and triggering apoptosis in MCF-7/TR cells. Further Western blot analysis indicated that the chemosensitizing effects of resveratrol were conferred with its modulation on endogenous TGF-ß production and Smad phosphorylation. In particular, 50 µM resveratrol had minor effects on MCF-7/TR cell proliferation, but could significantly attenuate endogenous TGF-ß production and the Smad pathway, ultimately leading to reversion of EMT. Collectively, our study highlighted distinct roles of EMT in tamoxifen resistance and resveratrol as a potential agent to overcome acquired tamoxifen resistance. The molecular mechanism of resveratrol chemosensitizing effects is, at least in part, TGF-ß/Smad-dependent.


Assuntos
Antineoplásicos/toxicidade , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Estilbenos/toxicidade , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Antagonistas de Estrogênios/farmacologia , Feminino , Humanos , Células MCF-7 , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Tamoxifeno/farmacologia , Fator de Crescimento Transformador beta/metabolismo
8.
Int J Mol Sci ; 13(6): 7776-7787, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22837726

RESUMO

Hypoxic pulmonary hypertension is a life-threatening emergency if untreated. Consistent pulmonary hypertension also leads to arteries and ventricular remodeling. The clinical therapeutic strategy for pulmonary hypertension and the corresponding remodeling mainly interacts with NO, angiotensin II (Ang II) and elevated endothelin (ET) targets. In the present study, we evaluated the effects of polydatin on hypoxia-induced pulmonary hypertension. It was observed that polydatin attenuated hypoxic pulmonary hypertension, reversed remodeling, and regulated NO, Ang II, ET contents in the serum and lung samples. However, forced activation of PKC signaling by its selective activator thymeleatoxin (THX) could abate the effects of polydatain. These results suggest that polydatin might be a promising candidate for hypoxic pulmonary treatment through interaction with PKC mechanisms.


Assuntos
Glucosídeos/farmacologia , Hipertensão Pulmonar/tratamento farmacológico , Hipóxia/tratamento farmacológico , Proteína Quinase C/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Remodelação Vascular/efeitos dos fármacos , Angiotensina II/metabolismo , Animais , Endotelinas/metabolismo , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/fisiopatologia , Hipóxia/metabolismo , Hipóxia/patologia , Hipóxia/fisiopatologia , Masculino , Óxido Nítrico/metabolismo , Ésteres de Forbol/farmacologia , Proteína Quinase C/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley
9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 38(6): 503-9, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-21033130

RESUMO

OBJECTIVE: Essential hypertension (EH) was a complex disease resulted from the interaction of cumulative effect of multiple genetic and environment factors. The relationship between the genetic polymorphisms in the transforming growth factor-beta1 (TGF-beta1), the blood levels and EH have been investigated, but the conclusions were different. Therefore, we investigate the relationship between the tagging single nucleotide polymorphisms (tSNPs) (rs1800469, rs2241716, rs11466345, rs2241715, rs4803455) in TGF-beta1 gene, blood levels and EH in the Han nationality population in Xinjiang, to clarity the pattern of linkage disequilibrium (LD) and the feature of the structure of haplotype. METHODS: Based on the case-control study,we selected 732 (365 EH patients,367 controls) Han Chinese population from the Boertonggu countryside of Shawan region in the Xinjiang Uygur Autonomous Region of China by random cluster sampling. After questionnaire and physical examination, we collected blood samples, and the blood levels of TGF-beta1 were quantified using sandwich ELISA. The polymorphisms of TGF-beta1 gene in the study groups were detected with SNaPshot system. The case-control study in a large group was carried out separately for each of the tSNP and followed up by haplotypes analyses to determine the relation between tSNPs of TGF-beta1 gene and EH in the Han population. RESULTS: (1) The frequencies of alleles A, G of rs11466345 of TGF-beta1 gene in EH group and control group were as follows: 69.7%, 30.3%, 74.4%, 25.6%, respectively. It was demonstrated that the G allele of the rs11466345 polymorphism occurred at a significantly higher frequency in EH patients than in healthy controls (30.3% vs. 25.6%, P < 0.05). The rs11466345G-allele carriers had a significantly increased risk of EH compared to rs11466345A-allele carrier (OR = 1.261; P < 0.05). The frequencies of genotypes and alleles of the other tSNPs of TGF-beta1 gene had no difference between EH patients and controls (P > 0.05). (2)Except the site of rs11466345, the other tSNPs were in strong LD, and no statistical differences were observed in haplotypes distribution in the followup study between case-control groups (P > 0.05). (3) There were no difference of TGF-beta1 levels between the different genotypes and alleles in tSNPs of TGF-beta1 gene (P > 0.05). CONCLUSIONS: (1) These results suggested that TGF-beta1 gene rs11466345 G allele was likely to be a genetic susceptibility factor for EH in the Xinjiang Han population, the other tSNPs perhaps had no association with EH of in the study groups. (2) Except rs11466345, the other tSNPs were in strong LD, and the haplotypes reconstructed by tSNPs might not be associated with EH in the Han nationality populations. (3) There was no association between the tSNP of TGF-beta1 gene and TGF-beta1 blood levels in the Xinjiang Han nationality population.


Assuntos
Hipertensão/genética , Polimorfismo de Nucleotídeo Único , Fator de Crescimento Transformador beta1/genética , Adulto , Alelos , Povo Asiático/genética , China/epidemiologia , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fator de Crescimento Transformador beta1/sangue
10.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 27(4): 463-8, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20677160

RESUMO

OBJECTIVE: To investigate the association of the transforming growth factor- beta 1 (TGF- beta 1) gene polymorphisms and blood TGF- beta 1 level with essential hypertension (EH) in Kazakh Chinese. METHODS: The polymorphisms of TGF- beta 1 gene in 354 Kazakh EH patients and 435 healthy controls were detected with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing. The blood level of TGF- beta 1 was quantified using specific sandwich ELISA. RESULTS: The frequencies of genotypes GG, GC and alleles G and C of +915G/C in Xinjiang Kazakh were 97.9%, 2.1% and 98.77%, 1.23%, respectively. No significantly difference was found between EH patients and controls (P>0.05). The frequencies of genotypes TT, TC, CC and alleles T and C of +869T/C in controls was 25.97%, 46.67%, 27.36%, 49.3% and 50.7%, respectively, the CC genotype or C allele in EH patients had significantly higher frequencies than controls [41.60% vs. 27.36%, and 62.2% vs. 50.7%, respectively (P<0.05)]. It was also shown that TGF- beta 1 +869 C allele carriers had significantly increased risk of EH compared with T allele carriers (OR=1.60, P=0.00). There was linkage disequilibrium (LD) between the two polymorphisms. The frequency of haplotype C-G in the EH group was significantly higher than that in controls (61.6% vs. 49.8%, P<0.05). There were no differences in TGF- beta 1 level among different genotypes or alleles in both +869T/C and +915G/C loci (P>0.05). CONCLUSION: The frequency of +915G/C variation of the TGF- beta 1 gene was very low in Kazakh and there was no homozygous variation. The +869 C allele was likely the genetic susceptibility factor for EH in the population. There was linkage disequilibrium in the polymorphisms of +869T/C and +915G/C. Haplotype C-G was the risk factor of EH.


Assuntos
Povo Asiático/etnologia , Predisposição Genética para Doença , Hipertensão/genética , Desequilíbrio de Ligação/genética , Fator de Crescimento Transformador beta1/genética , Adulto , Alelos , Povo Asiático/genética , Genótipo , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores de Risco
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(5): 1427-30, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19650506

RESUMO

An analysis method was developed to determine the chemical speciation of Cu, Zn, Fe and Mn in radix scutellariae decoction using atomic absorption spectroscopy(AAS). The decoction can be divided into suspension and soluble species by 0.45 microm filter membrane and the soluble species can be separated into organism and inorganic species by LSA-10 macroporous resin. These elements in water-soluble test samples can be divided into alcohol-soluble and water-soluble by adopting n-octyl alcohol-water allocation system in man-made gastric acidity. Then, the concentration of these elements was determined by AAS, which provided more chemical speciation information about these elements instead of the total amount of them only in radix scutellariae. Deteotion limit of Cu, Zn and Mn by using the method was all 0.01 microg x mL(-1) and was 0.02 microg x mL(-1) for Fe. The RSD was in the range of 1.5%-3.6% (n=11) and the recovery rate of soluble species and inorganic species were in range of 96.7%-105.0%. The method has been successfully applied to determine the chemical speciation of Cu, Zn, Fe and Mn in radix scutellariae, which was very important for overall study of radix scutellariae.


Assuntos
Metais Pesados/análise , Metais Pesados/química , Scutellaria baicalensis/química , Espectrofotometria Atômica/métodos , Cobre/análise , Cobre/química , Ferro/análise , Ferro/química , Cinética , Limite de Detecção , Manganês/análise , Manganês/química , Solventes/química , Zinco/análise , Zinco/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA