Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
1.
Sheng Li Xue Bao ; 76(2): 233-246, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38658373

RESUMO

The high-order cognitive and executive functions are necessary for an individual to survive. The densely bidirectional innervations between the medial prefrontal cortex (mPFC) and the mediodorsal thalamus (MD) play a vital role in regulating high-order functions. Pyramidal neurons in mPFC have been classified into several subclasses according to their morphological and electrophysiological properties, but the properties of the input-specific pyramidal neurons in mPFC remain poorly understood. The present study aimed to profile the morphological and electrophysiological properties of mPFC pyramidal neurons innervated by MD. In the past, the studies for characterizing the morphological and electrophysiological properties of neurons mainly relied on the electrophysiological recording of a large number of neurons and their morphologic reconstructions. But, it is a low efficient method for characterizing the circuit-specific neurons. The present study combined the advantages of traditional morphological and electrophysiological methods with machine learning to address the shortcomings of the past method, to establish a classification model for the morphological and electrophysiological properties of mPFC pyramidal neurons, and to achieve more accurate and efficient identification of the properties from a small size sample of neurons. We labeled MD-innervated pyramidal neurons of mPFC using the trans-synaptic neural circuitry tracing method and obtained their morphological properties using whole-cell patch-clamp recording and morphologic reconstructions. The results showed that the classification model established in the present study could predict the electrophysiological properties of MD-innervated pyramidal neurons based on their morphology. MD-innervated pyramidal neurons exhibit larger basal dendritic length but lower apical dendrite complexity compared to non-MD-innervated neurons in the mPFC. The morphological characteristics of the two subtypes (ET-1 and ET-2) of mPFC pyramidal neurons innervated by MD are different, with the apical dendrites of ET-1 neurons being longer and more complex than those of ET-2 neurons. These results suggest that the electrophysiological properties of MD- innervated pyramidal neurons within mPFC correlate with their morphological properties, indicating that the different roles of these two subclasses in local circuits within PFC, as well as in PFC-cortical/subcortical brain region circuits.


Assuntos
Córtex Pré-Frontal , Células Piramidais , Células Piramidais/fisiologia , Células Piramidais/citologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/citologia , Animais , Ratos , Núcleo Mediodorsal do Tálamo/fisiologia , Núcleo Mediodorsal do Tálamo/citologia , Masculino , Fenômenos Eletrofisiológicos , Vias Neurais/fisiologia , Vias Neurais/citologia , Aprendizado de Máquina , Ratos Sprague-Dawley , Técnicas de Patch-Clamp
2.
Ann Hum Biol ; 49(7-8): 280-290, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36382866

RESUMO

BACKGROUND: Existing evidence about associations between change in body mass index (BMI) and waist-to-height ratio (WHtR) change and high blood pressure are relatively limited. AIMS: We aimed to investigate the associations of general overweight (based on BMI) and abdominal obesity (based on WHtR) change with high blood pressure in Chinese children. SUBJECTS AND METHODS: A school-based cohort study in Ningbo region (China) was conducted among children with baseline evaluations in October 2016 with follow-up two years later. A total of 1432 children aged 11-13 years participated in this study. RESULTS: Our results showed that a change from normal BMI or WHtR to overweight or abdominal obesity in children was associated with high blood pressure (adjusted odds ratio (AOR), 2.62; p<0.05 or AOR, 2.79; p<0.05, respectively). In addition, an increased risk of high blood pressure was observed in children who maintained overweight or abdominal obesity (AOR, 1.67; p<0.05 or AOR, 1.69; p<0.05, respectively), but not in children who experienced remission to non-excess weight. Interestingly, children who increased BMI or WHtR had greater impact on SBP than on DBP. CONCLUSION: The 2-year longitudinal study indicated that general overweight or abdominal obesity can predict the risk factor of high blood pressure in children. However, children who remitted to non-excess weight did not exhibit an increased risk of high blood pressure.


Assuntos
Hipertensão , Obesidade Infantil , Humanos , Criança , Adolescente , Índice de Massa Corporal , Pressão Sanguínea/fisiologia , Sobrepeso/epidemiologia , Sobrepeso/complicações , Obesidade Infantil/epidemiologia , Obesidade Abdominal/epidemiologia , Estudos Longitudinais , Estudos de Coortes , Estudos Prospectivos , Fatores de Risco , Circunferência da Cintura
3.
Molecules ; 27(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36234919

RESUMO

High-fat (HF) diets and low-grade chronic inflammation contribute to the development of insulin resistance and type 2 diabetes (T2D), whereas n-3 polyunsaturated fatty acids (PUFAs), due to their anti-inflammatory effects, protect against insulin resistance. Interleukin (IL)-1ß is implicated in insulin resistance, yet how n-3 PUFAs modulate IL-1ß secretion and attenuate HF diet-induced insulin resistance remains elusive. In this study, a HF diet activated NLRP3 inflammasome via inducing reactive oxygen species (ROS) generation and promoted IL-1ß production primarily from adipose tissue preadipocytes, but not from adipocytes and induced insulin resistance in wild type (WT) mice. Interestingly, endogenous synthesized n-3 polyunsaturated fatty acids (PUFAs) reversed this process in HF diet-fed fat-1 transgenic mice although the HF diet induced higher weight gain in fat-1 mice, compared with the control diet. Mechanistically, palmitic acid (PA), the main saturated fatty acid in an HF diet inactivated AMPK and led to decreased GSK-3ß phosphorylation, at least partially through reducing Akt activity, which ultimately blocked the Nrf2/Trx1 antioxidant pathway and induced TXNIP cytoplasm translocation and NLRP3 inflammasome activation, whereas docosahexaenoic acid (DHA), the most abundant n-3 PUFA in fat-1 adipose tissue, reversed this process via inducing Akt activation. Our GSK-3ß shRNA knockdown study further revealed that GSK-3ß played a pivot role between the upstream AMPK/Akt pathway and downstream Nrf2/Trx1/TXNIP pathway. Given that NLRP3 inflammasome is implicated in the development of most inflammatory diseases, our results suggest the potential of n-3 PUFAs in the prevention or adjuvant treatment of NLRP3 inflammasome-driven diseases.


Assuntos
Diabetes Mellitus Tipo 2 , Ácidos Graxos Ômega-3 , Resistência à Insulina , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Proteínas de Transporte , Dieta Hiperlipídica/efeitos adversos , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Graxos/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Glicogênio Sintase Quinase 3 beta , Inflamassomos/metabolismo , Resistência à Insulina/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ácido Palmítico/farmacologia , Proteínas Proto-Oncogênicas c-akt , RNA Interferente Pequeno , Espécies Reativas de Oxigênio , Tiorredoxinas
4.
Molecules ; 24(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939790

RESUMO

A sensitive biotinylated indirect competitive enzyme-linked immunosorbent assay (Bic-ELISA) was developed to detect acetamiprid pesticides in pollen, based on the heterogeneous coating antigen and biotinylated anti-acetamiprid monoclonal antibody. Under optimized experimental conditions, the detection limit for the Bic-ELISA was 0.17 ng/mL and the linear range was 0.25⁻25 ng/mL. The cross-reactivities could be regarded as negligible for the biotinylated antibodies with their analogues except for thiacloprid (1.66%). Analyte recoveries for extracts of spiked pollen (camellia pollen, lotus pollen, rape pollen) ranged from 81.1% to 108.0%, with intra-day relative standard deviations (RSDs) of 4.8% to 10.9%, and the average reproducibility was 85.4% to 110.9% with inter-assay and inter-assay RSDs of 6.1% to 11.7%. The results of Bic-ELISA methods for the Taobao's website samples were largely consistent with HPLC-MS/MS. Therefore, the established Bic-ELISA methods would be conducive to the monitoring of acetamiprid in pollen.


Assuntos
Anticorpos Monoclonais/imunologia , Camellia/química , Ensaio de Imunoadsorção Enzimática/métodos , Lotus/química , Neonicotinoides/análise , Pólen/química , Neonicotinoides/imunologia
5.
New Phytol ; 210(3): 997-1010, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26720747

RESUMO

Plant germplasm resources with natural resistance against globally important toxigenic Fusarium are inadequate. CWP2, a Fusarium genus-specific antibody, confers durable resistance to different Fusarium pathogens that infect cereals and other crops, producing mycotoxins. However, the nature of the CWP2 target is not known. Thus, investigation of the gene coding for the CWP2 antibody target will likely provide critical insights into the mechanism underlying the resistance mediated by this disease-resistance antibody. Immunoblots and mass spectrometry analysis of two-dimensional electrophoresis gels containing cell wall proteins from Fusarium graminearum (Fg) revealed that a glyoxal oxidase (GLX) is the CWP2 antigen. Cellular localization studies showed that GLX is localized to the plasma membrane. This GLX efficiently catalyzes hydrogen peroxide production; this enzymatic activity was specifically inhibited by the CWP2 antibody. GLX-deletion strains of Fg, F. verticillioides (Fv) and F. oxysporum had significantly reduced virulence on plants. The GLX-deletion Fg and Fv strains had markedly reduced mycotoxin accumulation, and the expression of key genes in mycotoxin metabolism was downregulated. This study reveals a single gene-encoded and highly conserved cellular surface antigen that is specifically recognized by the disease-resistance antibody CWP2 and regulates both virulence and mycotoxin biosynthesis in Fusarium species.


Assuntos
Oxirredutases do Álcool/imunologia , Anticorpos/metabolismo , Membrana Celular/enzimologia , Resistência à Doença/imunologia , Fusarium/enzimologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Ergosterol/metabolismo , Imunofluorescência , Fusarium/genética , Fusarium/patogenicidade , Regulação Fúngica da Expressão Gênica , Proteínas de Fluorescência Verde/metabolismo , Modelos Biológicos , Mutação/genética , Micotoxinas/biossíntese , Oxirredução , Ligação Proteica , Reação em Cadeia da Polimerase em Tempo Real , Virulência
6.
Int J Mol Sci ; 17(11)2016 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-27809226

RESUMO

Dendritic cells (DCs), the most potent antigen-presenting cells, play a central role in the initiation, regulation, and maintenance of the immune responses. Vascular endothelial growth factor (VEGF) is one of the important cytokines in the tumor microenvironment (TME) and can inhibit the differentiation and functional maturation of DCs. To elucidate the potential mechanisms of DC dysfunction induced by VEGF, the effects of VEGF on the biophysical characteristics and motility of human mature DCs (mDCs) were investigated. The results showed that VEGF had a negative influence on the biophysical properties, including electrophoretic mobility, osmotic fragility, viscoelasticity, and transmigration. Further cytoskeleton structure analysis by confocal microscope and gene expression profile analyses by gene microarray and real-time PCR indicated that the abnormal remodeling of F-actin cytoskeleton may be the main reason for the deterioration of biophysical properties, motility, and stimulatory capability of VEGF-treated mDCs. This is significant for understanding the biological behavior of DCs and the immune escape mechanism of tumors. Simultaneously, the therapeutic efficacies may be improved by blocking the signaling pathway of VEGF in an appropriate manner before the deployment of DC-based vaccinations against tumors.


Assuntos
Fenômenos Biofísicos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Citoesqueleto/metabolismo , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Actinas/metabolismo , Apoptose/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Elasticidade , Eletroforese , Perfilação da Expressão Gênica , Ontologia Genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fragilidade Osmótica/efeitos dos fármacos , Pseudópodes/efeitos dos fármacos , Pseudópodes/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Migração Transendotelial e Transepitelial/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Viscosidade
7.
Phys Chem Chem Phys ; 17(16): 11077-87, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25826287

RESUMO

We report a theoretical study highlighting the thermoelectric properties of biological and synthetic DNA molecules. Based on an effective tight-binding model of duplex DNA and by using the nonequilibrium Green's function technique, the thermal conductance, electrical conductance, Seebeck coefficient and thermoelectric figure of merit in the system are numerically calculated by varying the asymmetries of energies and electronic hoppings in the backbone sites to simulate the environmental complications and fluctuations. We find that due to the multiple transport paths in the DNA molecule, the Fano antiresonance occurs, and enhances the Seebeck coefficient and the figure of merit. When the energy difference is produced in every opposite backbone site, the Dicke effect appears. This effect gives rise to a semiconducting-metallic transition, and enhances the thermoelectric efficiency of the DNA molecule remarkably. Moreover, as the Fano antiresonance point is close to the Dicke resonance one, a giant enhancement in the thermoelectric figure of merit in the DNA molecule has been found. These results provide a scenario to obtain effective routes to enhance the thermoelectric efficiency in the DNA molecules, and suggest perspectives for future experiments intending to control the thermoelectric transport in DNA-like nanodevices.


Assuntos
DNA/química , Condutividade Elétrica , Conformação de Ácido Nucleico , Temperatura , Modelos Moleculares
8.
Asian J Androl ; 26(4): 356-365, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38563741

RESUMO

The second-to-fourth digit (2D:4D) ratio is thought to be associated with prenatal androgen exposure. However, the relationship between the 2D:4D ratio and hypospadias is poorly understood, and its molecular mechanism is not clear. In this study, by analyzing the hand digit length of 142 boys with hypospadias (23 distal, 68 middle, and 51 proximal) and 196 controls enrolled in Shanghai Children's Hospital (Shanghai, China) from December 2020 to December 2021, we found that the 2D:4D ratio was significantly increased in boys with hypospadias ( P < 0.001) and it was positively correlated with the severity of the hypospadias. This was further verified by the comparison of control mice and prenatal low testosterone mice model obtained by knocking out the risk gene (dynein axonemal heavy chain 8 [ DNAH8 ]) associated with hypospadias. Furthermore, the discrepancy was mainly caused by a shift in 4D. Proteomic characterization of a mouse model validated that low testosterone levels during pregnancy can impair the growth and development of 4D. Comprehensive mechanistic explorations revealed that during the androgen-sensitive window, the downregulation of the androgen receptor (AR) caused by low testosterone levels, as well as the suppressed expression of chondrocyte proliferation-related genes such as Wnt family member 5a ( Wnt5a ), Wnt5b , Smad family member 2 ( Smad2 ), and Smad3 ; mitochondrial function-related genes in cartilage such as AMP-activated protein kinase ( AMPK ) and nuclear respiratory factor 1 ( Nrf-1 ); and vascular development-related genes such as myosin light chain ( MLC ), notch receptor 3 ( Notch3 ), and sphingosine kinase 1 ( Sphk1 ), are responsible for the limitation of 4D growth, which results in a higher 2D:4D ratio in boys with hypospadias via decreased endochondral ossification. This study indicates that the ratio of 2D:4D is a risk marker of hypospadias and provides a potential molecular mechanism.


Assuntos
Dedos , Hipospadia , Hipospadia/genética , Hipospadia/patologia , Hipospadia/metabolismo , Masculino , Animais , Humanos , Dedos/anatomia & histologia , Camundongos , Feminino , Testosterona/sangue , Testosterona/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Gravidez , Pré-Escolar , Criança , Estudos de Casos e Controles
9.
Anal Chem ; 85(22): 10992-9, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24128348

RESUMO

A sensitive and specific analytical method to detect ubiquitous aflatoxigenic Aspergillus pathogens is essential for monitoring and controlling aflatoxins. Four highly reactive chicken single-chain variable fragments (scFvs) against soluble cell wall proteins (SCWPs) from Aspergillus flavus were isolated by phage display. The scFv antibody AfSA4 displayed the highest activity toward both A. flavus and A. parasiticus and specifically recognized a surface target of their cell walls as revealed by immunofluorescence localization. Molecular modeling revealed a unique compact motif on the antibody surface mainly involving L-CDR2 and H-CDR3. As measured by surface plasmon resonance, AfSA4 fused to alkaline phosphatase had a higher binding capability and 6-fold higher affinity compared with AfSA4 alone. Immunoblot analyses showed that the fusion had good binding capacity to SCWP components from the two fungal species. Direct sandwich enzyme-linked immunosorbent assays with mouse antiaspergillus monoclonal antibody mAb2A8 generated in parallel as a capture antibody revealed that the detection limit of the two fungi was as low as 10(-3) µg/mL, 1000-fold more sensitive than that reported previously (1 µg/mL). The fusion protein was able to detect fungal concentrations below 1 µg/g of maize and peanut grains in both artificially and naturally contaminated samples, with at least 10-fold more sensitivity than that reported (10 µg/g) thus far. Thus, the fusion can be applied in rapid, simple, and specific diagnosis of Aspergillus contamination in field and stored food/feed commodities.


Assuntos
Fosfatase Alcalina/imunologia , Anticorpos Monoclonais/imunologia , Aspergilose/diagnóstico , Aspergillus/patogenicidade , Contaminação de Alimentos/análise , Anticorpos de Cadeia Única/imunologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , Arachis/química , Arachis/microbiologia , Aspergilose/imunologia , Aspergilose/microbiologia , Galinhas , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Biblioteca de Peptídeos , Conformação Proteica , Homologia de Sequência de Aminoácidos , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/metabolismo , Zea mays/química , Zea mays/microbiologia
10.
Ann Diagn Pathol ; 16(3): 190-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22209503

RESUMO

To explore the rationale for renal-sparing surgery as an alternative method to radical nephrectomy in the treatment of renal cell carcinoma (RCC), we analyzed clinical data from 94 patients diagnosed as having RCC. They were divided into 3 groups based on the maximum diameter of their tumor specimens. Group A had tumors size ranging from 0 to 4 cm, group B had tumors size ranging from 4 to 7 cm, and group C had tumors size greater than 7 cm. Tissue samples (5 cm) were taken from the upper pole side, lower pole side, and renal pelvic side of the tumor pseudocapsule; if the tumor was located on 1 pole of the kidney, samples were collected from 2 directions. The specimens were then embedded in paraffin and cut serially at segments 0 to 1, 1 to 3, and 3 to 5 cm. Staining with hematoxylin and eosin, anti-pancytokeratin, and vimentin was performed to determine tumor type and tumor infiltration. From the 94 patients analyzed, 2 patients in group A had RCC metastasis within 1 cm of tissue around the pseudocapsule, and 4 patients in groups B and C had lymph node metastasis without metastasis in the tissue 1 cm outside the pseudocapsule in all 3 directions described. There was no statistical significant difference found between the incidence of local metastasis of the various tumor sizes, suggesting that local metastasis of RCC is not associated with the size of the tumor. Based on the observation that incidences of local metastasis were low in early-stage RCC, we came to the conclusion that pseudocapsule of RCC tumor might have growth-limiting effect on the tumor enclosed. It is theoretically a safer and better surgical option for patients with RCC with a smaller size of tumor and indications for radical nephrectomy to undergo renal-sparing surgery with an excision margin of 1 cm of normal tissue around the pseudocapsule of the tumor.


Assuntos
Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Nefrectomia/métodos , Néfrons/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Queratinas/análise , Queratinas/biossíntese , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Vimentina/análise , Vimentina/biossíntese
11.
Int J Mol Sci ; 13(6): 7038-7056, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22837678

RESUMO

Fusarium verticillioides is the primary causal agent of Fusarium ear and kernel rot in maize, producing fumonisin mycotoxins that are toxic to humans and domestic animals. Rapid detection and monitoring of fumonisin-producing fungi are pivotally important for the prevention of mycotoxins from entering into food/feed products. Chicken-derived single-chain variable fragments (scFvs) against cell wall-bound proteins from F. verticillioides were isolated from an immunocompetent phage display library. Comparative phage enzyme-linked immunosorbant assays (ELISAs) and sequencing analyses identified four different scFv antibodies with high sensitivity. Soluble antibody ELISAs identified two highly sensitive scFv antibodies, FvCA3 and FvCA4, with the latter being slightly more sensitive. Three-dimensional modeling revealed that the FvCA4 may hold a better overall structure with CDRH3, CDRL1 and CDRL3 centered in the core region of antibody surface compared with that of other scFvs. Immunofluorescence labeling revealed that the binding of FvCA4 antibody was localized to the cell walls of conidiospores and hyphae of F. verticillioides, confirming the specificity of this antibody for a surface target. This scFv antibody was able to detect the fungal mycelium as low as 10(-2) µg/mL and contaminating mycelium at a quantity of 10(-2) mg/g maize. This is the first report that scFv antibodies derived from phage display have a wide application for rapid and accurate detection and monitoring of fumonisin-producing pathogens in agricultural samples.


Assuntos
Fusarium/metabolismo , Micotoxinas/química , Anticorpos de Cadeia Única/química , Sequência de Aminoácidos , Animais , Anticorpos/química , Antígenos/química , Sequência de Bases , Galinhas , Ensaio de Imunoadsorção Enzimática , Biblioteca Gênica , Imageamento Tridimensional , Immunoblotting , Microscopia de Fluorescência , Modelos Moleculares , Conformação Molecular , Dados de Sequência Molecular , Biblioteca de Peptídeos , Homologia de Sequência de Aminoácidos , Zea mays/metabolismo
12.
J Ethnopharmacol ; 298: 115602, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36030030

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The fruit of Ginkgo biloba L. (Ginkgo nuts) has been used for a long time as a critical Chinese medicine material to treat cough and asthma, as well as a disinfectant. Similar records were written in the Compendium of Materia Medica (Ben Cao Gang Mu, pinyin in Chinese) and Sheng Nong's herbal classic (Shen Nong Ben Cao Jing, pinyin in Chinese). Recent research has shown that Ginkgo biloba exocarp extract (GBEE) has the functions of unblocking blood vessels and improving brain function, as well as antitumour activity and antibacterial activity. GBEE was shown to inhibit methicillin-resistant Staphylococcus aureus (MRSA) biofilm formation as a traditional Chinese herb in our previous report in this journal. AIM OF THE STUD: yThe antibiotic resistance of clinical bacteria has recently become increasingly serious. Thus, this study aimed to investigate the Ginkgo biloba exocarp extract (GBEE) antibacterial lineage, as well as its effect and mechanism on S. haemolyticus biofilms. This study will provide a new perspective on clinical multidrug resistant (MDR) treatment with ethnopharmacology herbs. METHODS: The microbroth dilution assay was carried out to measure the antibacterial effect of GBEE on 13 types of clinical bacteria. Bacterial growth curves with or without GBEE treatment were drawn at different time points. The potential targets of GBEE against S. haemolyticus were screened by transcriptome sequencing. The effects of GBEE on bacterial biofilm formation and mature biofilm disruption were determined by crystal violet staining and scanning electron microscopy. The metabolic activity of bacteria inside the biofilm was assessed by colony-forming unit (CFU) counting and (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2HY-tetrazolium bromide (MTT) assay. Quantitative polymerase chain reaction (qPCR) was used to measure the gene expression profile of GBEE on S. haemolyticus biofilm-related factors. RESULTS: The results showed that GBEE has bacteriostatic effects on 3 g-positive (G+) and 2 g-negative (G-) bacteria among 13 species of clinical bacteria. The antibacterial effect of GBEE supernatant liquid was stronger than the antibacterial effect of GBEE supernviaould-like liquid. GBEE supernatant liquid inhibited the growth of S. epidermidis, S. haemolyticus, and E. faecium at shallow concentrations with minimum inhibitory concentrations (MICs) of 2 µg/ml, 4 µg/ml and 8 µg/ml, respectively. Genes involved in quorum sensing, two-component systems, folate biosynthesis, and ATP-binding cassette (ABC) transporters were differentially expressed in GBEE-treated groups compared with controls. Crystal violet, scanning electron microscopy (SEM) and MTT assays showed that GBEE suppressed S. haemolyticus biofilm formation in a dose-dependent manner. Moreover, GBEE supernatant liquid downregulated cidA, cidB and atl, which are involved in cell lysis and extracellular DNA (eDNA) release, as well as downregulated the cbp, ebp and fbp participation in encoding cell-surface binding proteins. CONCLUSIONS: GBEE has an excellent antibacterial effect on gram-positive bacteria and also inhibits the growth of gram-negative bacteria, such as A. baumannii (carbapenem-resistant Acinetobacter baumannii) CRABA and S. maltophilia. GBEE inhibits the biofilm formation of S. haemolyticus by altering the regulation and biofilm material-related genes, including the release of eDNA and cell-surface binding proteins.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus haemolyticus , Antibacterianos/farmacologia , Bactérias , Biofilmes , Violeta Genciana/farmacologia , Ginkgo biloba/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
13.
J Food Sci ; 86(10): 4704-4716, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34494660

RESUMO

Epidemiologic and preclinical studieshave shown that marine n-3 polyunsaturated fatty acids (n-3 PUFAs) elicit promising chemoprevention against breast cancer. Docosahexaenoic acid monoglyceride (MAG-DHA), a docosahexaenoic acid sn-1-monoacylglycerol does not required pancreatic lipase to be absorbed, eliciting a better bioavailability when compared with other formulations such as DHA-free fatty acid, DHA-triglycerol, or DHA-ethyl ester. However, the anticancer actions and underlying mechanisms of MAG-DHA on breast cancer remain to be assessed. In this study, MAG-DHA induced significant growth inhibition in MCF-7 and MDA-MB-231 breast cancer cells in a dose-dependent manner. MAG-DHA treatment (80 µM) led to 83.8 and 94.3% growth inhibition between MCF-7 and MDA-MB-231 cells, respectively. MAG-DHA-induced growth inhibition was tightly associated with apoptosis, as evidenced by increased active forms of caspase-3, poly (ADP-ribose) polymerase (PARP) and caspase-12. In particular, MAG-DHA-induced apoptosis was triggered by oxidative stress-mediated endoplasmic reticulum (ER) stress, as evidenced by activation of the PERK-eIF2α pathway in ER. MAG-DHA treatment also strongly suppressed the growth of E0771 murine breast cancer xenografts, significant differences of tumor volume were found between MAG-DHA group (0.271 cm3 ) and control group (0.875 cm3 ) after 15 daily MAG-DHA treatments. The in vitro antibreast cancer mechanism of MAG-DHA was supported by the in vivo xenograft model. In addition, MAG-DHA-induced ER stress concomitantly triggered autophagy in these cancer cells, and the induction of autophagy suppressed its ability to induce apoptotic cell death. Our data suggested that MAG-DHA as dietary supplement, in combination with autophagy inhibitors may be a useful therapeutic strategy in treating breast cancer.


Assuntos
Apoptose , Autofagia , Neoplasias da Mama , Estresse do Retículo Endoplasmático , Monoglicerídeos , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Xenoenxertos , Humanos , Peroxidação de Lipídeos , Células MCF-7 , Camundongos , Monoglicerídeos/farmacologia
14.
Sci Rep ; 11(1): 8741, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888811

RESUMO

When operating within the environments rich with sodium chloride, steel bars of reinforced concrete structures are often subject to corrosion caused by surrounding erosive materials, and the associated rust expansion force due to corrosion takes a critical role in determining the durability of relevant reinforced concrete structures. By investigating the corrosion course of steel reinforcement with theory of elasticity, a numerical rust expansion model is established for the moment of concrete surface rupture based on non-uniform sin function. Cuboid reinforced concrete specimen with squared cross sections is tested to analyze the rust expansion when concrete cracks due to corrosive forces. The utility of the established expansion model is validated by numerical simulation with Abaqus through the comparison between the associated outcomes. The impacts of steel bar diameter and concrete cover thickness on the magnitude of rust expansion force are discussed.

15.
J Ethnopharmacol ; 271: 113895, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33524512

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ginkgo biloba L. fruit, also known as Bai Guo, Ya Jiao Zi (in pinyin Chinese), and ginkgo nut (in English), has been used for many years as an important material in Chinese traditional medicine to treat coughs and asthma and as a disinfectant, as described in the Compendium of Materia Medica (Ben Cao Gang Mu, pinyin in Chinese), an old herbal book. Ginkgo nuts are used to treat phlegm-associated asthma, astringent gasp, frequent urination, gonorrhoea and turgidity; consumed raw to reduce phlegm and treat hangovers; and used as a disinfectant and insecticide. A similar record was also found in Sheng Nong's herbal classic (Shen Nong Ben Cao Jing, pinyin in Chinese). Recent research has shown that Ginkgo biloba L. exocarp extract (GBEE) can unblock blood vessels and improve brain function and exhibits antitumour and antibacterial activities. AIM OF STUDY: To investigate the inhibitory effect of Ginkgo biloba L. exocarp extract (GBEE) on methicillin-resistant S. aureus (MRSA) biofilms and assess its associated molecular mechanism. MATERIALS AND METHODS: The antibacterial effects of GBEE on S. aureus and MRSA were determined using the broth microdilution method. The growth curves of bacteria treated with or without GBEE were generated by measuring the CFU (colony forming unit) of cultures at different time points. The effects of GBEE on bacterial biofilm formation and mature biofilm disruption were determined by crystal violet staining. Quantitative polymerase chain reaction (qPCR) was used to measure the effects of GBEE on the gene expression profiles of MRSA biofilm-related factors at 6, 8, 12, 16 and 24 h. RESULTS: The minimum inhibitory concentration (MIC) of GBEE on S. aureus and MRSA was 4 µg/mL, and the minimum bactericidal concentration (MBC) was 8 µg/ml. Moreover, GBEE (4-12 µg/mL) inhibited S. aureus and MRSA biofilm formation in a dose-dependent manner. Interestingly, GBEE also destroyed mature biofilms of S. aureus and MRSA at 12 µg/ml. The expression of the MRSA biofilm-associated factor icaA and sarA were downregulated after 6 h of treatment with GBEE, while sigB was downregulated after 12 h. MeanwhileMeanwhile, icaR was upregulated at 12 h. In addition, GBEE also downregulated the virulence gene hld and inhibited the synthesis of staphyloxanthin. CONCLUSIONS: GBEE has excellent antibacterial effects against S. aureus and MRSA and inhibits their biofilm-forming ability by altering related gene expression.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Ginkgo biloba/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Staphylococcus aureus/fisiologia , Proteínas de Bactérias/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Virulência/efeitos dos fármacos
16.
Saudi J Biol Sci ; 27(2): 629-635, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32210681

RESUMO

The objective of this research is to solve the current medical problems of a high incidence of fungal infections in the lungs, high misdiagnosis rate, and high mortality. In this study, firstly, the logistic regression model was used to conduct. Risk factors of pulmonary fungal infection in respiratory department were analyzed. Then a model of pulmonary fungal infection in mice was constructed, and the expression difference of Progranulin (PGRN) in serum was detected by enzyme-linked immuno sorbent assay (ELISA). The expression of PGRN in lung tissues of mice infected by pulmonary fungi was detected by Western bolt method and quantitative polymerase chain reaction (PCR). The PGRN protein and mRNA expression in the lung epithelial cells of mice were detected after the infection. Results logistic regression model was used to analyze the main risk factors affecting pulmonary infection in mice. The risk factors of pulmonary fungal infection were indent catheter, hypoproteinemia, long-term use of glucocorticoid and long-term use of antibiotics. The PGRN content in serum was obviously higher than that before pulmonary fungal infection (P < 0.01). The expression of PGRN mRNA and protein in lung tissue was obviously higher than that before infection (P < 0.01). The expression of PGRN mRNA and protein in lung tissues of the infected group was obviously higher than that of the non-infected group (P < 0.01). The expression of PGRN protein in the lung epithelial cells of mice was obviously higher at 24 h after infection than before infection (P < 0.01), and the expression of PGRN mRNA was obviously higher at 12 h after infection than before infection (P < 0.01), indicating that PGRN is highly expressed in fungal pulmonary infection and is involved in disease progression. Therefore, this study provides a new idea for the diagnosis and treatment of fungal pulmonary infection in the later stage and has a good guiding significance for the diagnosis and treatment of fungal pulmonary infection.

17.
J Phys Chem Lett ; 11(20): 8721-8726, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32996769

RESUMO

The photon blockade induced by optical nonlinearity has been widely used to generate single-photon emission under optical driving in quantum optics. However, the same approach is difficult to achieve in electrically driven molecular junctions. Here we propose a scheme for tuning photon statistics via Fano-like interference effect in a system consisting of two molecules within one optical cavity. Under electrical pumping, a transition from photon bunching to antibunching takes place as a manifestation of the Fano-like interference. This effect persists even in the presence of the dipole-dipole interaction between molecules based on the parameters extracted from the experiments. Our proposal can be realized in current-carrying scanning tunneling microscope junctions.

18.
J Microbiol Biotechnol ; 30(5): 689-699, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32482934

RESUMO

Brevibacillus brevis GZDF3 is a gram-positive, plant growth-promoting rhizosphere bacterium (PGPR) isolated from the rhizosphere soil of Pinellia ternata (an important herb in traditional Chinese medicine). The GZDF3 strain produces certain active compounds, such as siderophores, which are the final metabolite products of non-ribosomal peptide synthetase (NRPS) and independent non-ribosomal peptide synthetase (NIS) activity. With the present study, we attempted to investigate the siderophore production characteristics and conditions of Bacillus sp. GZDF3. The antibacterial activity of the siderophores on pathogenic fungi was also investigated. Optimal conditions for the synthesis of siderophores were determined by single factor method, using sucrose 15 g/l, asparagine 2 g/l, 32°C, and 48 h. The optimized sucrose asparagine medium significantly increased the production of siderophores, from 27.09% to 54.99%. Moreover, the effects of different kinds of metal ions on siderophore production were explored here. We found that Fe3+ and Cu2+ significantly inhibited the synthesis of siderophores. The preliminary separation and purification of siderophores by immobilized-metal affinity chromatography (IMAC) provides strong antibacterial activity against Candida albicans. The synergistic effect of siderophores and amphotericin B was also demonstrated. Our results have shown that the GZDF3 strain could produce a large amount of siderophores with strong antagonistic activity, which is helpful in the development of new biological control agents.


Assuntos
Antifúngicos , Brevibacillus/metabolismo , Candida albicans/efeitos dos fármacos , Pinellia/microbiologia , Sideróforos , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Brevibacillus/isolamento & purificação , Meios de Cultura , Rizosfera , Sideróforos/metabolismo , Sideróforos/farmacologia
19.
Cell Biochem Biophys ; 78(3): 375-382, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32504355

RESUMO

Fumonisin B1 (FB1) is an important mycotoxin in nature and is a serious threat to human and animal health, but its specific target and molecular mechanism of the toxicity and potential carcinogenicity remain unclear. In this study, we first detected the effects of FB1 on the cell viability, biophysical properties, migration ability, and reactive oxygen species (ROS) of human umbilical vein endothelial cells (HUVECs). Subsequently, changes in the cytoskeletal structure and its binding proteins were analyzed by immunofluorescence and real-time PCR, respectively. The results showed that FB1 could inhibit the viability of HUVECs in a dose-dependent manner. After treatment of HUVECs with FB1, the hypotonic resistance, cell surface charges, cell membrane fluidity, and migration ability were weakened, whereas the ROS levels were significantly increased. Moreover, the cytoskeletal structure of the HUVECs was significantly changed, and the mRNA expression of some important actin-binding proteins was altered. Therefore, this study revealed that FB1 can affect the migration and cytoskeletal structure of HUVECs, which provides a new perspective for further understanding the molecular mechanisms of FB1 toxicity.


Assuntos
Movimento Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Fumonisinas/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Actinas/metabolismo , Sobrevivência Celular , Inibidores Enzimáticos/farmacologia , Fusarium , Humanos , Fragilidade Osmótica , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
20.
Int J Mol Med ; 24(1): 97-101, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19513541

RESUMO

PI-103, the first synthetic multitargeted compound which simultaneously inhibits PI3Kalpha and mammalian target of rapamycin (mTOR) shows high antitumor activity in glioma xenografts. In the present study, clear antitumor activity was observed with PI-103 treatment in two gefitinib-resistant non-small cell lung cancer (NSCLC) cell lines, A549 and H460, by simultaneously inhibiting p70s6k phosporylation and Akt phosphorylation in response to mTOR inhibition. In addition, H460 cells with activating mutations of PIK3CA were more sensitive to PI-103 than A549 cells with wild-type PIK3CA. PI-103 was found to inhibit growth by causing G0-G1 arrest in A549 and H460 cells. Western blotting showed that PI-103 induced down-regulation of cyclin D1 and E1 and simultaneously up-regulated p21 and p27, associated with arrest in the G0-G1 phase of the cell cycle. Furthermore, p53, the tumor suppressor which transcriptionally regulates p21, was also upregulated with PI-103 treatment. Collectively, our results suggest that multitargeted intervention is the most effective tumor therapy, and the cooperative blockade of PI3Kalpha and mTOR with PI-103 shows promise for treating gefitinib-resistant NSCLC.


Assuntos
Antineoplásicos/farmacologia , Furanos/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Piridinas/farmacologia , Pirimidinas/farmacologia , Carcinoma Pulmonar de Células não Pequenas , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases , Resistencia a Medicamentos Antineoplásicos , Gefitinibe , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares , Mutação , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Quinazolinas/farmacologia , Serina-Treonina Quinases TOR , Proteínas Supressoras de Tumor/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA