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1.
Nano Lett ; 24(31): 9505-9510, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39046144

RESUMO

In this contribution, we report on the visualization of 12-crown-4 molecular diffusion behavior within a single-crystal particle of covalent organic framework-300 (COF-300) using operando dark-field optical microscopy. The diffusion area and front of 12-crown-4 are directly tracked in real time, offering key information for quantifying the diffusion coefficient (D). The direction of the diffusion and variation of D reveal intraparticle and interparticle heterogeneity. Notably, an unexpected hydration-accelerated diffusion process of 12-crown-4 within the pore channels of COF-300 is captured, in which a relatively low concentration of 12-crown-4 aqueous solution induces a fast diffusion, whereas the pure 12-crown-4 liquid cannot access the framework. The observed acceleration diffusion is demonstrated to arise from the hydrogen-bonding interactions between surface water molecules of hydrated 12-crown-4 and the imine groups of COF-300. These findings expand the mechanistic understanding of the noncovalent interactions between COFs and crown ethers (CEs), which will help to design and prepare CE-based COFs with improved performance.

2.
J Endocrinol ; 250(1): 1-12, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-33970125

RESUMO

Our previous study has demonstrated maternal high-fat diet (HFD) caused sex-dependent cardiac hypertrophy in adult male, but not female offspring. The present study tested the hypothesis that estrogen normalizes maternal HFD-induced cardiac hypertrophy by regulating angiotensin II receptor (ATR) expression in adult female offspring. Pregnant rats were divided into the normal diet (ND) and HFD (60% kcal fat) groups. Ovariectomy (OVX) and 17ß-estradiol (E2) replacement were performed on 8-week-old female offspring. Maternal HFD had no effect on left ventricular (LV) wall thickness, cardiac function and molecular markers of cardiac hypertrophy function in sham groups. However, maternal HFD caused cardiac hypertrophy of offspring in OVX groups, which was abrogated by E2 replacement. In addition, maternal HFD had no effect on ERα and ERß in sham groups. In contrast, HFD significantly decreased ERα, but not ERß in OVX groups. In sham groups, there was no difference in the cardiac ATR type 1 (AT1R) and ATR type 2 (AT2R) between ND and HFD offspring. HFD significantly increased AT2R, but not AT1R in OVX groups. Furthermore, maternal HFD resulted in decreased glucocorticoid receptors (GRs) binding to the glucocorticoid response elements at the AT2R promoter, which was due to decreased GRs in hearts from OVX offspring. These HFD-induced changes in OVX groups were abrogated by E2 replacement. These results support a key role of estrogen in the sex difference of maternal HFD-induced cardiac hypertrophy in offspring, and suggest that estrogen protects female offspring from cardiac hypertrophy in adulthood by regulating AT2R.


Assuntos
Cardiomegalia/etiologia , Dieta Hiperlipídica/efeitos adversos , Estrogênios/fisiologia , Efeitos Tardios da Exposição Pré-Natal , Receptor Tipo 2 de Angiotensina/metabolismo , Animais , Estradiol , Receptor alfa de Estrogênio/metabolismo , Feminino , Masculino , Miocárdio/metabolismo , Gravidez , Distribuição Aleatória , Ratos Sprague-Dawley , Fatores Sexuais
3.
Proteomics ; 21(10): e2000262, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33763969

RESUMO

Macrophages are sentinels in the organism which can resist and destroy various bacteria through direct phagocytosis. Here, we reported that expression level of mitochondrial ribosomal protein S35 (Mrps35) continued to decrease over infection time after Listeria monocytogenes (L. monocytogenes) infected macrophages. Our results indicated that knockdown Mrps35 increased the load of L. monocytogenes in macrophages. This result supported that Mrps35 played the crucial roles in L. monocytogenes infection. Moreover, we performed the comprehensive proteomics to analyze the differentially expressed protein of wild type and Mrps35 Knockdown Raw264.7 cells by L. monocytogenes infection over 6 h. Based on the results of mass spectrometry, we presented a wide variety of hypotheses about the mechanism of Mrps35 controlling the L. monocytogenes intracellular proliferation. Among them, experiments confirmed that Mrps35 and 60S ribosomal protein L22-like 1 (Rpl22l1) were a functional correlation or potentially a compensatory mechanism during L. monocytogenes infection. This study provided new insights into understanding that L. monocytogenes infection changed the basic synthesis or metabolism-related proteins of host cells.


Assuntos
Listeria monocytogenes , Proliferação de Células , Macrófagos , Fagocitose , Proteômica
4.
Nat Prod Bioprospect ; 9(3): 209-214, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31028545

RESUMO

Two new C21 steroidal glycosides, paniculatumosides H and I, together with four known ones were isolated from the roots of Cynanchum paniculatum (Bge.) Kitag. Their structures were identified by spectroscopic methods including extensive 1D and 2D NMR techniques. All compounds were subjected to detect the anti-tobacco mosaic virus (TMV) activities and their cytotoxities against three human tumor cell lines (SMMC-7721, MDA-MB-231 and A549). The results showed that compounds 1 and 5 exhibited potent protective activities against TMV, while 2, 4 and 6 had moderate effects on the SMMC-7721 cancer cells viability.

5.
J Nat Med ; 73(2): 339-352, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30523551

RESUMO

The aim of this study was to elucidate the gastroprotective activity and possible mechanism of involvement of araloside A (ARA) against ethanol- and aspirin-induced gastric ulcer in mice. The experimental mice were randomly divided into control, model, omeprazole (20 mg/kg, orally) and ARA (10, 20 and 40 mg/kg, orally). Gastric ulcer in mice was induced by intragastric administration of 80% ethanol (10 mL/kg) containing 15 mg/mL aspirin 4 h after drug administration on day 7. The results indicated that ARA could significantly raise gastric juice volume and acidity; ameliorate gastric mucosal blood flow, gastric binding mucus volume, ulcer index and ulcer inhibition rate; suppress H+/K+-ATPase activity, which was confirmed by computer-aided docking simulations; inhibit the release of mitochondrial cytochrome c into the cytoplasm; inhibit caspase-9 and caspase-3 activities and down-regulate mRNA expression levels; down-regulate the mRNA and protein expressions of apoptosis protease-activating factor-1 and protein expression of cleaved poly(ADP ribose) polymerase-1; and up-regulate Bcl-2 mRNA and protein expressions and down-regulate Bax mRNA and protein expressions, thus elevating the Bcl-2/Bax ratio in a dose-dependent manner. Histopathological observations further provided supportive evidence for the aforementioned results. The results demonstrated that ARA exerted beneficial gastroprotective effects on alcohol- and aspirin-induced gastric ulcer in mice, which was related to suppressing H+/K+-ATPase activity as well as pro-apoptotic protein expression, and promoting anti-apoptotic protein expression, thus alleviating gastric mucosal injury and cell death.


Assuntos
Antiulcerosos/uso terapêutico , Mucosa Gástrica/efeitos dos fármacos , ATPase Trocadora de Hidrogênio-Potássio/efeitos dos fármacos , Ácido Oleanólico/análogos & derivados , Saponinas/uso terapêutico , Úlcera Gástrica/prevenção & controle , Animais , Antiulcerosos/isolamento & purificação , Antiulcerosos/farmacologia , Fator Apoptótico 1 Ativador de Proteases/metabolismo , Aralia/química , Aspirina/efeitos adversos , Caspase 3/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Avaliação Pré-Clínica de Medicamentos , Etanol/efeitos adversos , Suco Gástrico/efeitos dos fármacos , Mucosa Gástrica/irrigação sanguínea , Mucosa Gástrica/metabolismo , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Masculino , Camundongos , Mitocôndrias/metabolismo , Simulação de Acoplamento Molecular , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Ácido Oleanólico/uso terapêutico , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Poli(ADP-Ribose) Polimerase-1/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Distribuição Aleatória , Fluxo Sanguíneo Regional/efeitos dos fármacos , Saponinas/isolamento & purificação , Saponinas/farmacologia , Úlcera Gástrica/induzido quimicamente
6.
J Nat Prod ; 81(5): 1209-1218, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29667820

RESUMO

The phytochemical study of Euphorbia resinifera afforded 18 structurally diverse diterpenoids, including 14 new ingol-type diterpenoids, euphorblins A-N (1-14), a new rhamnofolane diterpenoid, euphorblin O (15), and three known analogues (16-18). The structures of these compounds were deduced using 2D NMR spectroscopy and NOE experiments. The structure of compound 1 was confirmed by single-crystal X-ray crystallography. The abilities of the compounds to enhance lysosomal biosynthesis were evaluated through LysoTracker Red staining. Among the 10 active compounds, compounds 2, 4, and 18 showed remarkable immunofluorescence strength, and their LysoTracker staining intensities were 155.9%, 143.5%, and 140.7%, respectively, greater than that of the control. A series of lysosomal genes were also found to be upregulated by these compounds, which further confirms their ability to induce lysosome biosynthesis and suggests that these diterpenoids have potential as lead compounds for the development of drugs for the treatment of lysosome-related diseases.


Assuntos
Diterpenos/química , Diterpenos/farmacologia , Euphorbia/química , Lisossomos/efeitos dos fármacos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética/métodos , Ressonância Magnética Nuclear Biomolecular/métodos
7.
Int J Med Mushrooms ; 19(3): 233-242, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28605338

RESUMO

Phytoestrogen has previously been proposed as an alternative to hormone replacement therapy. Hispolon has been found to have phytoestrogenic properties. However, the possible effects of hispolon on estrogen receptors and other related molecules remain to be determined. This study was performed mainly to confirm the estrogenic function of hispolon as it relates to estrogen receptors, aromatase, and cyclooxygenase 2 (COX-2). Hispolon was shown to increase the serum 17ß-estradiol in vivo. Immunohistochemical staining methods showed that hispolon exhibited a biphasic effect on ERα/ß and aromatase expression in MCF-7 cells. Hispolon could also significantly inhibit aromatase activity, assessed using the enzyme-linked immunosorbent assay. Western blotting showed that COX-2 and aromatase could be inhibited by hispolon. These results further prove the phytoestrogenic features of hispolon and explore some pharmacological mechanisms that suggest that hispolon could be useful in the treatment of breast cancers or other gynecologic diseases.


Assuntos
Aromatase/metabolismo , Basidiomycota/química , Catecóis/farmacologia , Ciclo-Oxigenase 2/metabolismo , Receptores de Estrogênio/metabolismo , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Western Blotting , Catecóis/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Ensaio de Imunoadsorção Enzimática , Humanos , Células MCF-7 , Fitoestrógenos/isolamento & purificação , Fitoestrógenos/farmacologia
8.
Chemosphere ; 164: 128-133, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27588571

RESUMO

Industrialization and urbanization have led to increasingly serious levels of atmospheric heavy metal pollution, which is one of the main sources of heavy metals to terrestrial ecosystems. Therefore, it is essential to quantify atmospheric fluxes and explore their potential effects on natural ecosystems and human welfare. We monitored water-soluble heavy metals (lead (Pb), cadmium (Cd), and chromium (Cr)) in rainfalls on a monthly basis in 2013 and 2014, at 31 field stations located in typical natural Chinese ecosystems. The average soluble Pb, Cd, and Cr deposition was 1.90 ± 1.54, 0.28 ± 0.25, and 0.96 ± 0.48 mg m-2 yr-1, respectively, with a large variation among the different sites. Generally, the atmospheric deposition of soluble Pb, Cd, and Cr was higher in the southwest, central, south, and north China than in the northwest and northeast China, Inner Mongolia, and Qinghai-Tibet. As expected, the atmospheric heavy soluble metal deposition fluxes were significantly correlated with the number of vehicles (Ps < 0.1). The wet deposition of soluble Pb and Cr was positively correlated with oil and coal consumption, unlike Cd deposition. Moreover, soluble Pb and Cd in atmospheric wet deposition were positively correlated with the contents of Pb and Cd in soil at different regions. In this study, atmospheric heavy metal deposition through rainfall in typical natural ecosystems in China is assessed at the national scale, alerting potential ecological hazards resulting from an increasing atmospheric heavy metal deposition and providing a basis for future studies.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , China , Ecossistema , Monitoramento Ambiental
9.
Oncoimmunology ; 4(4): e1001230, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26137399

RESUMO

A characteristic immunopathology of human cancers is the induction of tumor antigen-specific T lymphocyte responses within solid tumor tissues. Current strategies for immune monitoring focus on the quantification of the density and differentiation status of tumor-infiltrating T lymphocytes; however, properties of the TCR repertoire ‒ including antigen specificity, clonality, as well as its prognostic significance ‒ remain elusive. In this study, we enrolled 28 gastric cancer patients and collected tumor tissues, adjacent normal mucosal tissues, and peripheral blood samples to study the landscape and compartmentalization of these patients' TCR ß repertoire by deep sequencing analyses. Our results illustrated antigen-driven expansion within the tumor compartment and the contracted size of shared clonotypes in mucosa and peripheral blood. Most importantly, the diversity of mucosal T lymphocytes could independently predict prognosis, which strongly underscores critical roles of resident mucosal T-cells in executing post-surgery immunosurveillance against tumor relapse.

10.
ACS Comb Sci ; 17(7): 409-12, 2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26086733

RESUMO

A chemiluminescence (CL) sensing method for amino acid discrimination based on luminol functionalized silver nanoparticles (LumAgNPs) has been developed. Luminescence emission in the presence of hydrogen peroxide under neutral conditions was characterized in three ways: the time required for the signal to appear (Ta), the time required to reach maximum luminescence (Tp), and CL intensity. These factors were found to change upon interaction of the nanoparticles with various amino acids, leading to distinct response patterns characteristic of each analyte. Seven amino acids (l-cysteine, l-proline, l-phenylalanine, l-arginine, l-threonine, l-glutamic acid, and l-tyrosine) were identified at a concentration of 10 ng/mL. This sensitivity is about 3 orders of magnitude better than that of recently reported methods based on fluorescent sensor arrays using cucurbit[n]uril and comparable to high-performance liquid chromatography. Application to 27 unknown samples gave a 96.3% success rate at the 10 ng/mL level.


Assuntos
Aminoácidos/análise , Nanopartículas Metálicas/química , Prata/química , Cromatografia Líquida de Alta Pressão , Medições Luminescentes , Luminol/química , Estrutura Molecular
11.
Chin J Physiol ; 56(2): 83-9, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23589924

RESUMO

Cyclin G1 is the only cyclin that has either positive or negative effects on cell growth. Our previous study found decreased expression of cyclin G1 in human endometrial carcinoma tissues compared with normal endometrial tissues. The study aimed to evaluate cyclin G1 expression and its effect on proliferation of human endometrial carcinoma cells (ECCs). Cyclin G1-GFP (green fluorescence protein) plasmid was constructed and transfected into various differentiated human ECCs, including Ishikawa, HEC-1-B and KLE cells, and proliferation of the transfected cells was determined by the CCK-8 method. Exogenous cyclin G1 mRNA and protein were measured by RT-PCR and Western blot, respectively, and GFP signal was monitored by fluorescence microscopy. Chinese hamster ovary (CHO) cells were transfected with the same constructs as a cell control. Cyclin G1-GFP-transfected Ishikawa cells were further treated with MG132, an inhibitor of proteasome, to analyze if low expression of cyclin G1 is related to its abnormal degradation in ECCs. Ectopic expression of exogenous cyclin G1 was found to significantly suppress the proliferation of Ishikawa and HEC-1-B cells but not KLE cells. Compared with cyclin G1-transfected CHO cells, exogenous cyclin G1 protein expression was low in Ishikawa and HEC-1-B cells, and was undetectable in KLE cells. However, all ECC lines and CHO cells expressed similar levels of exogenous cyclin G1 and GFP mRNA. MG132 treatment increased cyclin G1 protein expression in cyclin G1-GFP-transfected Ishikawa cells. This is the first study to present evidence to suggest that cyclin G1 exerts negative control on proliferation of ECCs. Exogenous cyclin G1 shows different protein expression levels in ECCs with different malignancies, and cyclin G1 protein is highly unstable and is rapidly degraded in ECCs.


Assuntos
Ciclina G1/fisiologia , Neoplasias do Endométrio/patologia , Animais , Células CHO , Linhagem Celular Tumoral , Proliferação de Células , Cricetinae , Cricetulus , Ciclina G1/genética , Feminino , Humanos , RNA Mensageiro/análise , Transfecção
12.
Reprod Sci ; 19(11): 1205-10, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22649121

RESUMO

Cyclin G1 protein is expressed in normal endometrial epithelial cells in a progesterone-dependent manner. It is an important mediator of the inhibiting effect of progesterone on cell proliferation. Moreover, the expression of cyclin G1 is also found to be decreased in human endometrial carcinoma cells (ECCs). To study the mechanism of decrease in the expression levels of cyclin G1, 3 ECC cell lines, Ishikawa, HEC-1-B, and KLE cells were treated with progesterone (P(4)). The KLE cells, in which progesterone receptor (PR) expression was absent, were transfected with PR-expressing plasmid before treatment with P(4). The results showed that cyclin G1 expression increased in Ishikawa and HEC-1-B cells after treatment with P(4), additionally the cell proliferation was suppressed but not in KLE cells. When the PR-expressing plasmid was transfected into KLE cells, the effect of P(4) was restored. Our data suggest that the deficiency of progesterone and its receptors is an important cause of the decreased expression of cyclin G1 in endometrial carcinoma, which may account for carcinogenesis and development of endometrial carcinomas.


Assuntos
Ciclina G1/genética , Neoplasias do Endométrio/metabolismo , Progesterona/fisiologia , Receptores de Progesterona/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Progesterona/farmacologia , RNA Mensageiro/análise , Receptores de Progesterona/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 43(2): 166-9, 2012 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-22650023

RESUMO

OBJECTIVE: To study the effect of protein phosphatase 2A (PP2A) in the negative regulation of progesterone on the proliferation of mouse endometrial epithelial cells (EECs). METHODS: Mouse EECs were isolated and cultured in vitro, which were divided into four groups when they grown to confluence: control group (P4) was treated with 1 micromol/L progesterone only, group A, B and C were treated respectively with 1 micromol/L progesterone and different concentrations of okadaic acid (5 nmol/L, 10 nmol/L and 20 nmol/L). After 24 h, the numbers of cells in different phases of the cell cycle were counted with flow cytometry. RESULTS: The effect of OA on mouse EECs was concentration-dependent. Compared with control group of P4, the change of cell cycle procession in group A was not obvious. Lower proportion of cells in G1 and G2/M phase and higher proportion of cells in S phase in group B, higher proportion of cells in G1 and S phase and lower proportion of cells in G2/M phase in group C were observed. CONCLUSION: Adequate dose OA inhibiting PP2A could release the inhibitory effect of progesterone on proliferation of mouse EECs obviously, this suggested that PP2A was involved in the inhibitory effect of progesterone on proliferation of EECs by influencing the process of cell cycle.


Assuntos
Proliferação de Células/efeitos dos fármacos , Endométrio/citologia , Células Epiteliais/citologia , Progesterona/farmacologia , Proteína Fosfatase 2/antagonistas & inibidores , Animais , Ciclo Celular , Células Cultivadas , Feminino , Camundongos , Ácido Okadáico/farmacologia
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