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1.
Cell Death Dis ; 14(4): 269, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37059730

RESUMO

Hypoxia contributes to the initiation and progression of glioblastoma by regulating a cohort of genes called hypoxia-regulated genes (HRGs) which form a complex molecular interacting network (HRG-MINW). Transcription factors (TFs) often play central roles for MINW. The key TFs for hypoxia induced reactions were explored using proteomic analysis to identify a set of hypoxia-regulated proteins (HRPs) in GBM cells. Next, systematic TF analysis identified CEBPD as a top TF that regulates the greatest number of HRPs and HRGs. Clinical sample and public database analysis revealed that CEBPD is significantly up-regulated in GBM, high levels of CEBPD predict poor prognosis. In addition, CEBPD is highly expressed in hypoxic condition both in GBM tissue and cell lines. For molecular mechanisms, HIF1α and HIF2α can activate the CEBPD promotor. In vitro and in vivo experiments demonstrated that CEBPD knockdown impaired the invasion and growth capacity of GBM cells, especially in hypoxia condition. Next, proteomic analysis identified that CEBPD target proteins are mainly involved in the EGFR/PI3K pathway and extracellular matrix (ECM) functions. WB assays revealed that CEBPD significantly positively regulated EGFR/PI3K pathway. Chromatin immunoprecipitation (ChIP) qPCR/Seq analysis and Luciferase reporter assay demonstrated that CEBPD binds and activates the promotor of a key ECM protein FN1 (fibronectin). In addition, the interactions of FN1 and its integrin receptors are necessary for CEBPD-induced EGFR/PI3K activation by promoting EGFR phosphorylation. Furthermore, GBM sample analysis in the database corroborated that CEBPD is positively correlated with the pathway activities of EGFR/PI3K and HIF1α, especially in highly hypoxic samples. At last, HRPs are also enriched in ECM proteins, indicating that ECM activities are important components of hypoxia induced responses in GBM. In conclusion, CEPBD plays important regulatory roles in the GBM HRG-MINW as a key TF, which activates the EGFR/PI3K pathway through ECM, especially FN1, mediated EGFR phosphorylation.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/genética , Glioblastoma/metabolismo , Transdução de Sinais , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fatores de Transcrição , Proteômica , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Hipóxia/genética , Hipóxia/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Matriz Extracelular/metabolismo , Proteína delta de Ligação ao Facilitador CCAAT/metabolismo
2.
Front Med (Lausanne) ; 9: 952611, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36203769

RESUMO

Objective: The study aimed to determine the prevalence and pathogens of invasive fungal infection (IFI) among intensive care unit (ICU) patients. The next goal was to investigate the association between empirical antifungal treatment and mortality in ICU patients. Methods: Using microbiological events, we identified all ICU patients with IFI and then retrieved electronic clinical data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The data were statistically analyzed using t-tests, chi-square tests, log-rank tests, and Cox regression. Results: The most commonly reported fungi were Candida (72.64%) and Aspergillus (19.08%). The most frequently prescribed antifungal medication was fluconazole (37.57%), followed by micafungin (26.47%). In the survival study of ICU patients and patients with sepsis, survivors were more likely to receive empirical antifungal treatment. In contrast, non-empirical antifungal therapy was significantly associated with poor survival in patients with positive blood cultures. We found that the current predictive score makes an accurate prediction of patients with fungal infections challenging. Conclusions: Our study demonstrated that empirical antifungal treatment is associated with decreased mortality in ICU patients. To avoid treatment delays, novel diagnostic techniques should be implemented in the clinic. Until such tests are available, appropriate empirical antifungal therapy could be administered based on a model that predicts the optimal time to initiate antifungal therapy. Additional studies should be conducted to establish more accurate predictive models in the future.

3.
FEBS Open Bio ; 12(7): 1406-1418, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35560988

RESUMO

As a model system, Escherichia coli has been used to study various life processes. A dramatic paradigm shift has occurred in recent years, with the study of single proteins moving toward the study of dynamically interacting proteins, especially protein-protein interaction (PPI) networks. However, despite the importance of PPI networks, little is known about the intrinsic nature of the network structure, especially high-dimensional topological properties. By introducing general hypergeometric distribution, we reconstruct a statistically reliable combined PPI network of E. coli (E. coli-PPI-Network) from several datasets. Unlike traditional graph analysis, algebraic topology was introduced to analyze the topological structures of the E. coli-PPI-Network, including high-dimensional cavities and cycles. Random networks with the same node and edge number (RandomNet) or scale-free networks with the same degree distribution (RandomNet-SameDD) were produced as controls. We discovered that the E. coli-PPI-Network had special algebraic typological structures, exhibiting more high-dimensional cavities and cycles, compared to RandomNets or, importantly, RandomNet-SameDD. Based on these results, we defined degree of involved q-dimensional cycles of proteins (q-DCprotein ) in the network, a novel concept that relies on the integral structure of the network and is different from traditional node degree or hubs. Finally, top proteins ranked by their 1-DCprotein were identified (such as gmhB, rpoA, rplB, rpsF and yfgB). In conclusion, by introducing mathematical and computer technologies, we discovered novel algebraic topological properties of the E. coli-PPI-Network, which has special high-dimensional cavities and cycles, and thereby revealed certain intrinsic rules of information flow underlining bacteria biology.


Assuntos
Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Escherichia coli/genética , Escherichia coli/metabolismo , Modelos Biológicos , Mapeamento de Interação de Proteínas/métodos , Proteínas/metabolismo
4.
BMC Cancer ; 22(1): 86, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35057766

RESUMO

BACKGROUND: Glioblastoma (GBM) can be divided into subtypes according to their genomic features, including Proneural (PN), Neural (NE), Classical (CL) and Mesenchymal (ME). However, it is a difficult task to unify various genomic expression profiles which were standardized with various procedures from different studies and to manually classify a given GBM sample into a subtype. METHODS: An algorithm was developed to unify the genomic profiles of GBM samples into a standardized normal distribution (SND), based on their internal expression ranks. Deep neural networks (DNN) and convolutional DNN (CDNN) models were trained on original and SND data. In addition, expanded SND data by combining various The Cancer Genome Atlas (TCGA) datasets were used to improve the robustness and generalization capacity of the CDNN models. RESULTS: The SND data kept unimodal distribution similar to their original data, and also kept the internal expression ranks of all genes for each sample. CDNN models trained on the SND data showed significantly higher accuracy compared to DNN and CDNN models trained on primary expression data. Interestingly, the CDNN models classified the NE subtype with the lowest accuracy in the GBM datasets, expanded datasets and in IDH wide type GBMs, consistent with the recent studies that NE subtype should be excluded. Furthermore, the CDNN models also recognized independent GBM datasets, even with small set of genomic expressions. CONCLUSIONS: The GBM expression profiles can be transformed into unified SND data, which can be used to train CDNN models with high accuracy and generalization capacity. These models suggested NE subtype may be not compatible with the 4 subtypes classification system.


Assuntos
Aprendizado Profundo , Perfilação da Expressão Gênica/métodos , Glioblastoma/classificação , Redes Neurais de Computação , Algoritmos , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica , Genômica , Humanos , Distribuição Normal
5.
Biomed Pharmacother ; 143: 112128, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34492424

RESUMO

Gender differences have important biological significance for medical research. In this study, a bias towards males was identified in animal experiments of Damp-Heat Syndrome in traditional Chinese medicine, as was first proposed by a data mining method. Combined with the correlation between Damp-Heat Syndrome in traditional Chinese medicine and Gender differences, it was considered that Gender-related factors have a significant influence on the development of Damp-Heat Syndrome in traditional Chinese medicine. However, most traditional Chinese medicine studies ignore the key significance of Gender-related factors. This study emphasises that the development of modern traditional Chinese medicine research needs to pay full attention to the biological significance of Gender-related factors and to apply this concept to the research on the Gender equivalence strategy in basic research and the practice of personalised medical diagnosis and clinical treatment.


Assuntos
Disparidades nos Níveis de Saúde , Sistema Imunitário/fisiopatologia , Inflamação/fisiopatologia , Medicina Tradicional Chinesa , Caracteres Sexuais , Animais , Mineração de Dados , Modelos Animais de Doenças , Feminino , Humanos , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/terapia , Mediadores da Inflamação/metabolismo , Masculino , Fatores de Risco , Fatores Sexuais , Síndrome , Biologia de Sistemas
6.
SAGE Open Med ; 8: 2050312120958908, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33110602

RESUMO

OBJECTIVE: We aimed to identify and represent factors associated with thrombocytopenia in intensive care unit, especially the pathogens and drugs related to severe and extremely thrombocytopenia. Then, we aim to compare the mortality of platelet transfusion and non-transfusion in patients with different degrees of thrombocytopenia. METHODS: We identified all thrombocytopenic patients in intensive care unit by using platelet-specific values and then extracted electronic health records from our Hospital Information System. Data were statistically analyzed with t test, chi-square test, and logistic regression. RESULTS: We found that infections (32.7%) were the most frequent cause associated with thrombocytopenia, followed by sepsis shock (3.93%) and blood loss (2.99%). Meanwhile, antifungals (p = 0.002) and bacterial infection (p = 0.037) were associated with severe and extremely severe thrombocytopenia. Finally, we found that the mortality of platelet transfusion and non-transfusion in patients was statistically significant for patients with platelet counts between 30 and 49/nL (χ2 = 9.719, p = 0.002). CONCLUSION: Infection and sepsis emerged as two primary factors associated with thrombocytopenia in intensive care unit. Meanwhile, antifungals and bacterial infection were associated with platelet counts less than 49/nL. Finally, platelet transfusion may be associated with reduced mortality in patients with platelet counts between 30 and 49/nL.

7.
Cell Mol Neurobiol ; 39(8): 1093-1114, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31203532

RESUMO

Hypoxia regulated genes (HRGs) formed a complex molecular interaction network (MINW), contributing to many aspects of glioblastoma (GBM) tumor biology. However, little is known about the intrinsic structures of the HRGs-MINW, mainly due to a lack of analysis tools to decipher MINWs. By introducing general hyper-geometric distribution, we obtained a statistically reliable gene set of HRGs (SR-HRGs) from several datasets. Next, MINWs were reconstructed from several independent GBM expression datasets. Algebraic topological analysis was performed to quantitatively analyze the amount of equivalence classes of cycles in various dimensions by calculating the Betti numbers. Persistent homology analysis of a filtration of growing networks was further performed to examine robust topological structures in the network by investigating the Betti curves, life length of the cycles. Random networks with the same number of node and edge and degree distribution were produced as controls. As a result, GBM-HRGs-MINWs reconstructed from different datasets exhibited great consistent Betti curves to each other, which were significantly different from that of random networks. Furthermore, HRGs-MINWs reconstructed from normal brain expression datasets exhibited topological structures significantly different from that of GBM-HRGs-MINWs. Analysis of cycles in GBM-HRGs-MINWs revealed genes that had clinical implications, and key parts of the cycles were also identified in reconstructed protein-protein interaction networks. In addition, the cycles are composed by genes involved in the Warburg effect, immune regulation, and angiogenesis. In summary, GBM-HRGs-MINWs contained abundant molecular interacting cycles in different dimensions, which are composed by genes involved in multiple programs essential for the tumorigenesis of GBM, revealing novel interaction diagrams in GBM and providing novel potential therapeutic targets.


Assuntos
Redes Reguladoras de Genes , Glioblastoma/genética , Glioblastoma/imunologia , Glicólise , Hipóxia Tumoral/genética , Encéfalo/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glioblastoma/patologia , Humanos
8.
Nanomedicine ; 14(3): 745-758, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29341934

RESUMO

Discovery and development of new antibacterial drugs against multidrug resistant bacterial strains have become more and more urgent. Antisense oligonucleotides (ASOs) show immense potential to control the spread of resistant microbes due to its high specificity of action, little risk to human gene expression, and easy design and synthesis to target any possible gene. However, efficient delivery of ASOs to their action sites with enough concentration remains a major obstacle, which greatly hampers their clinical application. In this study, we reviewed current progress on delivery strategies of ASOs into bacteria, focused on various non-virus gene vectors, including cell penetrating peptides, lipid nanoparticles, bolaamphiphile-based nanoparticles, DNA nanostructures and Vitamin B12. The current review provided comprehensive understanding and novel perspective for the future application of ASOs in combating bacterial infections.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Oligonucleotídeos Antissenso/farmacologia , Animais , Infecções Bacterianas/microbiologia , Humanos , Nanopartículas
9.
Oncotarget ; 7(30): 47808-47820, 2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-27329597

RESUMO

Hypoxia contributes to the maintenance of stem-like cells in glioblastoma (GBM), and activates vascular mimicry and tumor resistance to anti-angiogenesis treatments. The present study examined the expression patterns and biological significance of hypoxia-inducible protein 2 (HIG2, also known as HILPDA) in GBM. HIG2 was highly expressed in gliomas and was correlated with tumor grade, and high HIG2 expression independently predicted poor GBM patient prognosis. HIG2 was upregulated during hypoxia and by hypoxia mimics, and HIG2 knockdown in GBM cells inhibited cell proliferation and invasion. HIF1α bound to the HIG2 promoter and increased its expression in GBM cells, and HIG2 upregulated HIF1α expression. Reconstruction of a HIG2-related molecular network using bioinformatics methods revealed that HIG2 is closely correlated with angiogenesis genes, such as VEGFA, in GBM. HIG2 levels positively correlated with VEGFA in GBM samples. In addition, treatment of transplanted xenograft nude mice with bevacizumab (anti-angiogenesis therapy) resulted in HIG2 upregulation at late stages. We conclude that HIG2 is overexpressed in GBM and upregulated by hypoxia, and is a potential novel therapeutic target. HIG2 overexpression is an independent prognostic indicator and may promote tumor resistance to anti-angiogenesis treatments.


Assuntos
Bevacizumab/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Proteínas de Neoplasias/biossíntese , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos Imunológicos/farmacologia , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/irrigação sanguínea , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Nus , Neovascularização Patológica/metabolismo , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Arch Pharm Res ; 39(10): 1349-1355, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26077886

RESUMO

A series of bisoumarin (1-4) and dihydropyran (5-8) derivatives were successfully synthesized as new antibacterial agents. The molecular structures of three representative compounds 1, 5 and 7 were confirmed by single crystal X-ray diffraction study. Among these compounds tested toward Staphylococcus aureus (S. aureus ATCC 29213), methicillin-resistant S. aureus (MRSA XJ 75302), vancomycin-intermediate S. aureus (Mu50 ATCC 700699), and USA 300 (Los Angeles County clone, LAC), compounds 1 and 2 displayed the most potent antibacterial activity. Additionally, the HB energy in biscoumarins 1-4 was calculated by density functional theory (DFT) [B3LYP/6-31G*] method.


Assuntos
Antibacterianos/classificação , Antibacterianos/síntese química , Cumarínicos/classificação , Cumarínicos/síntese química , Antibacterianos/farmacologia , Cumarínicos/farmacologia , Cristalografia por Raios X/métodos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Testes de Sensibilidade Microbiana/métodos
11.
Nanomedicine ; 11(2): 329-39, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25461286

RESUMO

The pandemic of multidrug-resistant Gram negative bacteria (GNB) is a worldwide healthcare concern, and very few antibiotics are being explored to match the clinical challenge. Recently, amino-terminated poly(amidoamine) (PAMAM) dendrimers have shown potential to function as broad antimicrobial agents. However, PAMAM displays a generation dependent cytotoxicity to mammalian cells and low selectivity on bacterial cells, which limits PAMAM to be developed as an antibacterial agent for systemic administration. We conjugated G3 PAMAM with LED209, a specific inhibitor of quorum sensor QseC of GNB, to generate a multifunctional agent PAMAM-LED209. Intriguingly, PAMAM-LED209 showed higher selectivity on GNB and lower cytotoxicity to mammalian cells, yet remained strong antibacterial activity. PAMAM-LED209 also inhibited virulence gene expression of GNB, and did not induce antibiotic-resistance. The present work firstly demonstrated that PAMAM-LED209 conjugate had a highly selective anti-GNB activity and low cytotoxicity, which offered a feasible strategy for combating multidrug-resistant GNB infections. FROM THE CLINICAL EDITOR: This research team demonstrated that a novel PAMAM-LED209 conjugate had highly selective activity against Gram-negative bacteria, coupled with low cytotoxicity, offering a potential strategy for combating multidrug-resistant infections.


Assuntos
Dendrímeros/administração & dosagem , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções/tratamento farmacológico , Sulfonamidas/administração & dosagem , Animais , Antibacterianos/uso terapêutico , Proteínas de Bactérias/antagonistas & inibidores , Dendrímeros/química , Bactérias Gram-Negativas/patogenicidade , Humanos , Infecções/microbiologia , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Proteínas Repressoras/antagonistas & inibidores , Sulfonamidas/química , Virulência/efeitos dos fármacos
12.
Neurosci Lett ; 584: 135-40, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25451725

RESUMO

The biological roles of stem cell marker LGR5, the receptor for the Wnt-agonistic R-spondins, for nervous system are poorly known. Bioinformatics analysis in normal human brain tissues revealed that LGR5 is closely related with neuron development and functions. Interestingly, LGR5 and its ligands R-spondins (RSPO2 and RSPO3) are specifically highly expressed in projection motor neurons in the spinal cord, brain stem and cerebral. Inhibition of Notch activity in neural stem cells (NSCs) increased the percentage of neuronal cells and promoted LGR5 expression, while activation of Notch signal decreased neuronal cells and inhibited the LGR5 expression. Furthermore, knockdown of LGR5 inhibited the expression of neuronal markers MAP2, NeuN, GAP43, SYP and CHRM3, and also reduced the expression of genes that program the identity of motor neurons, including Isl1, Lhx3, PHOX2A, TBX20 and NEUROG2. Our data demonstrated that LGR5 is highly expressed in motor neurons in nervous system and is involved in their development by regulating transcription factors that program motor neuron identity.


Assuntos
Células-Tronco Neurais/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Encéfalo/citologia , Encéfalo/fisiologia , Diferenciação Celular , Células Cultivadas , Humanos , Neurônios Motores/citologia , Neurônios Motores/fisiologia , Células-Tronco Neurais/citologia , Medula Espinal/citologia , Medula Espinal/fisiologia
13.
Phytother Res ; 29(3): 373-80, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25414071

RESUMO

A new kind of pregnane-type alkaloid, 20α-dimethylamino-3ß-senecioylamino-16ß-hydroxy-pregn-5-ene (K-6), was isolated from Pachysandra terminalis Sieb. et Zucc., and its antibacterial activity against MRSA and MRSE was evaluated. We found that K-6 showed antibacterial effects against MRSA and MRSE with minimum inhibitory concentration values (25 mg/L), but did not induce antibiotic resistance in bacteria easily. The administration of K-6 dose-dependently improved the animal survival rate of mice infected with MRSA, with survival rates of 36.34% and 66.67% in the low-dose and high-dose groups, respectively. The protective effects were associated with the reduction of the bacterial titers in the blood and with the morphological amelioration of infected tissues. Scanning and transmission electron microscopy analyses indicated that the cytoplasm shrink of bacterial cells led to noticeable gaps between the cell membrane and cell cytoplasm, and the severely damaged cell membrane resulted in leakage of intracellular content, which ultimately caused the lethal effect of K-6 on bacteria. These findings demonstrated that K-6 is a potential agent against MRSA and MRSE.


Assuntos
Alcaloides/farmacologia , Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pachysandra/química , Pregnanos/farmacologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana
14.
Org Biomol Chem ; 12(29): 5528-35, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-24947818

RESUMO

Four dicoumarols (DC, 2-PyDC, 3-PyDC and 4-PyDC) were synthesized and characterized via IR, (1)H NMR, HRMS, and single crystal X-ray crystallography. Two classical intramolecular O-H···O hydrogen bonds (HBs) stabilized their structures. The total HB energies in DC, 2-PyDC, 3-PyDC and 4-PyDC were calculated with the density functional theory (DFT) [B3LYP/6-31G*] method. The in vitro antibacterial activity of DC, 2-PyDC, 3-PyDC and 4-PyDC against Staphylococcus aureus (S. aureus ATCC 29213), methicillin-resistant S. aureus (MRSA XJ 75302), vancomycin-intermediate S. aureus (Mu50 ATCC 700699), and USA 300 (Los Angeles County clone, LAC) was evaluated by observing the minimum inhibitory concentration and time-kill curves. The results showed that among all the compounds, 2-PyDC exhibited the most potent antibacterial activity.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Dicumarol/síntese química , Dicumarol/farmacologia , Modelos Moleculares , Antibacterianos/toxicidade , Morte Celular , Cristalografia por Raios X , Dicumarol/química , Dicumarol/toxicidade , Elétrons , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Ligação de Hidrogênio , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Teoria Quântica , Eletricidade Estática , Termodinâmica
15.
Eur J Pharmacol ; 721(1-3): 151-7, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24076183

RESUMO

Four novel 4-hydroxycoumarin derivatives (4-MBH, 3-MBH, 4-MDT and 3-MDT) were successfully synthesized and their structures were verified by single-crystal X-ray crystallography. All target compounds were evaluated for their in vitro antibacterial activity against Staphylococcus aureus (S. aureus ATCC 29213), methicillin-resistant S. aureus (MRSA XJ 75302), vancomycin-intermediate S. aureus (Mu50 ATCC 700699), and USA 300 (Los Angeles County clone, LAC). The minimum inhibitory concentration and time-kill curves were obtained for the test compounds and antibiotics. Among the tested compounds, 3-MBH showed the most potent antibacterial activities.


Assuntos
4-Hidroxicumarinas/síntese química , 4-Hidroxicumarinas/farmacologia , Antibacterianos/síntese química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , 4-Hidroxicumarinas/química , Antibacterianos/química , Técnicas de Química Sintética , Cristalografia por Raios X , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Relação Estrutura-Atividade , Fatores de Tempo
16.
Cell Mol Neurobiol ; 33(6): 851-65, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23793848

RESUMO

The biological functional roles of LGR5 (leucine-rich repeat containing G protein-coupled receptor 5, also known as GPR49), a novel potential marker for stem-like cells in glioblastoma (GSCs), is poorly acknowledged. Here, we demonstrated that LGR5 was detected in glioblastoma tissues and GSCs. Bioinformatics analysis revealed that LGR5 is closely related to neurogenesis and neuronal functions, and preferentially expressed in Proneural subtype of GBMs. Furthermore, LGR5 is regulated by Proneural factor OLIG2, which is important for both neurogenesis and GSC maintenance. Biological experiments in GSC cells validated the bioinformatics analysis results and revealed that LGR5 regulated the tumor sphere formation capacity, an important stem cell property for GSCs. Therefore, LGR5 expression may be functionally correlated with the neurogenic competence, and be regulated by OLIG2 in GSCs.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Glioma/metabolismo , Glioma/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Adolescente , Adulto , Idoso , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Diferenciação Celular/genética , Biologia Computacional , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes/genética , Glioblastoma/genética , Glioblastoma/patologia , Glioma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Neurônios/patologia , Fator de Transcrição 2 de Oligodendrócitos , Análise de Componente Principal , Receptores Acoplados a Proteínas G/genética , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Células Tumorais Cultivadas , Adulto Jovem
17.
Neuro Oncol ; 15(7): 865-79, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23645533

RESUMO

BACKGROUND: A proportion of glioblastoma stemlike cells (GSCs) expressing endothelial cell marker CDH5 (vascular-endothelial-cadherin or CD144) can transdifferentiate into endothelial cells and form blood vessels. However, the implications of CDH5 expression in gliomas and how it is regulated in GSCs remain to be clarified. METHODS: The mRNA and protein levels of CDH5 were detected in glioma samples and cultured cell lines, and the prognostic value of the CDH5 expression level for GBM patients was evaluated. Bioinformatics analysis was performed to reveal the potential functional roles of CDH5 in glioblastoma multiforme. Gene knockdown induced by short hairpin RNA, chromatin immunoprecipitation analysis, and a vasculogenic tube formation assay were performed to investigate the relationships among hypoxia, CDH5 expression level, and angiogenesis. RESULTS: CDH5 was overexpressed in gliomas, correlated with tumor grades, and was an independent adverse prognostic predictor for glioblastoma multiforme patients. CDH5 was specifically activated in GSCs but not in non-GSCs or neural stem cells, and CDH5(+) cells could produce xenografts in immunocompromised mice. Bioinformatics analysis demonstrated that CDH5 might interact directly with hypoxia-inducible factor (HIF)2α. CDH5 expression was significantly upregulated in GSCs, but not in non-GSCs or normal neural stem cells, under a 1% O2 condition. Both HIF1α and HIF2α positively regulated CDH5 level in GSCs and could bind to the promoter of CDH5. Furthermore, CDH5 contributed to the vasculogenic mimicry of GSCs, especially under hypoxic conditions. CONCLUSIONS: The specific expression of CDH5 in GSCs may contribute to GSC-derived neovasculogenesis in glioblastoma multiforme, especially under hypoxic conditions, revealing novel tumorigenic mechanisms contributed by GSCs.


Assuntos
Antígenos CD/metabolismo , Neoplasias Encefálicas/patologia , Caderinas/metabolismo , Glioblastoma/patologia , Hipóxia , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/patologia , Células-Tronco Neurais/patologia , Adulto , Animais , Antígenos CD/genética , Apoptose , Western Blotting , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Caderinas/antagonistas & inibidores , Caderinas/genética , Proliferação de Células , Células Cultivadas , Imunoprecipitação da Cromatina , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Gradação de Tumores , Células-Tronco Neoplásicas/metabolismo , Neovascularização Patológica/metabolismo , Células-Tronco Neurais/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Neurosci Bull ; 29(1): 111-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23179066

RESUMO

There is no effective drug to treat Alzheimer's disease (AD), a neurodegenerative disease affecting an estimated 30 million people around the world. Strongly supported by preclinical and clinical studies, amyloid-beta (Aß) may be a target for developing drugs against AD. Meanwhile, the fact that localized neuronal death/loss and synaptic impairment occur in AD should also be considered. Neuronal regeneration, which does not occur normally in the mammalian central nervous system, can be promoted by neurotrophic factors (NTFs). Evidence from clinical trials has shown that both Aß clearance and NTFs are potentially effective in treating AD, thus a new approach combining Aß clearance and administration of NTFs may be an effective therapeutic strategy.


Assuntos
Doença de Alzheimer/terapia , Peptídeos beta-Amiloides/metabolismo , Fatores de Crescimento Neural/uso terapêutico , Doença de Alzheimer/metabolismo , Animais , Humanos , Taxa de Depuração Metabólica/fisiologia
19.
Zhong Yao Cai ; 36(9): 1477-80, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24620696

RESUMO

OBJECTIVE: To study the neurotrophic effects of senegenin on the expression of MAP2 mRNA and BDNF mRNA in cultured cerebral cortical neurons. METHODS: The newborn rat cerebral cortex neurons were cultured in vitro. LDH assay was used to investigate the effect of senegenin on the neuronal viability and reverse transcription polymerase chain reaction (RT-PCR) was carried out to determine the expression level of MAP2 mRNA and BDNF mRNA. RESULTS: LDH assay showed that senegenin at the concentration of 0. 5 micromol/L,1 micromol/L and 2 micromol/L could obviously enhance the survival of cells and the survival rates were in dose-dependent manner to some extent. Moreover, the low, medium and high concentrations of senegenin significantly increased the expression of MAP2 mRNA and BDNF mRNA. CONCLUSION: The study suggests that suitable dose of senegenin can increase the expression of MAP2 mRNA and BDNF mRNA in cultured cerebral cortical neurons, and its mechanism needs further study.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Córtex Cerebral/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Animais Recém-Nascidos , Fator Neurotrófico Derivado do Encéfalo/genética , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , L-Lactato Desidrogenase/metabolismo , Masculino , Neuritos/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Neurol Res ; 34(9): 901-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22909461

RESUMO

OBJECTIVE: To investigate the mechanisms underlying protocatechuic acid (PCA)-induced neurotrophic effects on cultured cortical neurons. METHODS: The mRNA expression of microtubule-associated protein 2 (MAP2) and brain-derived neurotrophic factor (BDNF) were measured by real-time quantitative PCR (qPCR). Subsequently, antagonists were used to study the signaling pathways activated by PCA and western blotting was used to detect the phosphorylation level of kinase-related protein. RESULTS: The mRNA expression of MAP2 and BDNF were upregulated in neurons treated with PCA compared with vehicle control. PCA-induced neurite outgrowth and neuronal survival in cultured cortical neurons were significantly inhibited by ZM241385 (an A(2A) receptor antagonist) and LY294002 (a PI3K inhibitor), but not by K252a (a TrkA receptor antagonist), GÖ6976 (a protein kinase C inhibitor) and PD98059 (a MEK inhibitor). PCA enhanced the phosphorylation of Akt, which could be blocked by LY294002. CONCLUSION: The PI3K/Akt signaling pathway might play an important role in the neurotrophic activity of PCA.


Assuntos
Anticarcinógenos/farmacologia , Córtex Cerebral/citologia , Hidroxibenzoatos/farmacologia , Neurônios/efeitos dos fármacos , Proteína Oncogênica v-akt/metabolismo , Animais , Animais Recém-Nascidos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/genética , Fosforilação/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
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