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1.
J Med Genet ; 61(6): 543-548, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38228392

RESUMO

BACKGROUND: METHODS: The GRN mutations, especially of the loss of function type, are causative of frontotemporal dementia (FTD). However, several GRN variants can be found in other neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease. So far, there have been over 300 GRN mutations reported globally. However, the genetic spectrum and phenotypic characteristics have not been fully elucidated in Chinese population.The participants were from the dementia cohort of Peking Union Medical College Hospital (n=1945). They received history inquiry, cognitive evaluation, brain imaging and exome sequencing. The dementia subjects carrying the rare variants of the GRN were included in this study. Those with the pathogenic or likely pathogenic variants of other dementia-related genes were excluded. RESULTS: 14 subjects carried the rare variants of GRN. They were clinically diagnosed with behavioural variant of FTD (n=2), non-fluent/agrammatic variant primary progressive aphasia (PPA, n=3), semantic variant PPA (n=1), AD (n=6) and mixed dementia (n=2). 13 rare variants of GRN were found, including 6 novel variants (W49X, S226G, M152I, A91E, G79E and A303S). The most prevalent symptom was amnesia (85.7%, 12/14), followed by psychiatric and behavioural disorder (78.6%, 11/14). In terms of lobar atrophy, temporal atrophy/hypometabolism was the most common (85.7%, 12/14), followed by parietal atrophy/hypometabolism (78.6%, 11/14). CONCLUSION: The novel GRN variants identified in this study contribute to enrich the GRN mutation repertoire. There is phenotypic similarity and diversity among Chinese patients with the GRN mutations.


Assuntos
Demência Frontotemporal , Estudos de Associação Genética , Mutação , Progranulinas , Humanos , Progranulinas/genética , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Estudos de Coortes , Demência/genética , Demência/patologia , Demência/epidemiologia , Povo Asiático/genética , Sequenciamento do Exoma , Fenótipo , China/epidemiologia , Predisposição Genética para Doença , População do Leste Asiático
2.
J Antimicrob Chemother ; 79(4): 903-917, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38412335

RESUMO

BACKGROUND: MDR Staphylococcus aureus infections, along with the severity of biofilm-associated infections, continue to threaten human health to a great extent. It necessitates the urgent development of novel antimicrobial and antibiofilm agents. OBJECTIVES: To reveal the mechanism and target of cinacalcet as an antibacterial and antimicrobial agent for S. aureus. METHODS: Screening of non-antibiotic drugs for antibacterial and antibiofilm properties was conducted using a small-molecule drug library. In vivo efficacy was assessed through animal models, and the antibacterial mechanism was studied using quantitative proteomics, biochemical assays, LiP-SMap, BLI detection and gene knockout techniques. RESULTS: Cinacalcet, an FDA-approved drug, demonstrated antibacterial and antibiofilm activity against S. aureus, with less observed development of bacterial resistance. Importantly, cinacalcet significantly improved survival in a pneumonia model and bacterial clearance in a biofilm infection model. Moreover, the antibacterial mechanism of cinacalcet mainly involves the destruction of membrane-targeted structures, alteration of energy metabolism, and production of reactive oxygen species (ROS). Cinacalcet was found to target IcaR, inhibiting biofilm formation through the negative regulation of IcaADBC. CONCLUSIONS: The findings suggest that cinacalcet has potential for repurposing as a therapeutic agent for MDR S. aureus infections and associated biofilms, warranting further investigation.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Humanos , Staphylococcus aureus , Cinacalcete/farmacologia , Cinacalcete/uso terapêutico , Complexo Ferro-Dextran/uso terapêutico , Reposicionamento de Medicamentos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Membrana Celular , Biofilmes , Testes de Sensibilidade Microbiana
3.
J Biol Chem ; 298(4): 101794, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35248531

RESUMO

Epigenetic regulation plays substantial roles in human pathophysiology, which provides opportunities for intervention in human disorders through the targeting of epigenetic pathways. Recently, emerging evidence from preclinical studies suggested the potential in developing therapeutics of Alzheimer's disease (AD) by targeting bromodomain containing protein 4 (BRD4), an epigenetic regulatory protein. However, further characterization of AD-related pathological events is urgently required. Here, we investigated the effects of pharmacological degradation or inhibition of BRD4 on AD cell models. Interestingly, we found that both degradation and inhibition of BRD4 by ARV-825 and JQ1, respectively, robustly increased the levels of amyloid-beta (Aß), which has been associated with the neuropathology of AD. Subsequently, we characterized the mechanisms by which downregulation of BRD4 increases Aß levels. We found that both degradation and inhibition of BRD4 increased the levels of BACE1, the enzyme responsible for cleavage of the amyloid-beta protein precursor (APP) to generate Aß. Consistent with Aß increase, we also found that downregulation of BRD4 increased AD-related phosphorylated Tau (pTau) protein in our 3D-AD human neural cell culture model. Therefore, our results suggest that downregulation of BRD4 would not be a viable strategy for AD intervention. Collectively, our study not only shows that BRD4 is a novel epigenetic component that regulates BACE1 and Aß levels, but also provides novel and translational insights into the targeting of BRD4 for potential clinical applications.


Assuntos
Doença de Alzheimer , Proteínas de Ciclo Celular , Epigênese Genética , Fatores de Transcrição , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
J Antimicrob Chemother ; 78(8): 1859-1870, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37288948

RESUMO

BACKGROUND: CpxR is a critical regulator in bacterial adaptation to various harmful stresses, and is known to regulate bacterial resistance to commonly used antibiotics, such as aminoglycosides, ß-lactams and polypeptides. However, the detailed study of functional residues of CpxR remains insufficient. OBJECTIVES: To investigate the contribution of Lys219 to CpxR's function in regulating antibiotic resistance of Escherichia coli. METHODS: We performed sequence alignment and conservative analysis of the CpxR protein and constructed mutant strains. We then performed electrophoretic mobility shift assay, real-time quantitative PCR assay, determination of reactive oxygen species (ROS) levels, molecular dynamics simulation, conformational analysis and circular dichroism. RESULTS: All mutant proteins (K219Q, K219A and K219R) lost the cpxP DNA-binding ability. Additionally, the three complemented strains eK219A, eK219Q, and eK219R exhibited lower resistance to copper toxicity and alkaline pH toxicity than eWT. Molecular dynamics analysis revealed that mutation of Lys219 leads to looser and more unstable conformation of CpxR, leading to its decreased binding affinity with downstream genes. Moreover, the Lys219 mutation resulted in the down-regulation of efflux pump genes (acrD, tolC, mdtB and mdtA), leading to the accumulation of antibiotics inside the cells and an increase in ROS production, which significantly reduces antibiotic resistance. CONCLUSIONS: The mutation of the key residue Lys219 causes a conformational change that results in the loss of regulatory ability of CpxR, which may potentially reduce to antibiotic resistance. Therefore, this study suggests that targeting the highly conserved sequence of CpxR could be a promising strategy for the development of new antibacterial drugs.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Regulação Bacteriana da Expressão Gênica
5.
Biol Pharm Bull ; 45(8): 1027-1035, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35908886

RESUMO

The reactive oxygen species (ROS) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway play critical roles in the pathogenesis of prostate cancer by modulating cell proliferation. Picropodophyllin (PPP), an inhibitor of the insulin-like growth factor 1 receptor (IGF-1R), exerts significant antitumor effects via the PI3K/AKT signaling pathway. However, the effects of PPP on prostate cancer via ROS production and the PI3K/AKT signaling pathway remain elusive. Herein, we focused on examining the antitumor effects of PPP on DU145 and LNCaP human prostate cancer cells to determine the possible molecular mechanism. Our data indicated that the inhibitory effect of PPP on the proliferation of DU145 and LNCaP human prostate cancer cells was mediated by apoptosis induction and cell cycle blockade. Furthermore, PPP significantly influenced the expression of apoptosis-related, cell cycle, ROS production, and PI3K/AKT signaling proteins. These findings suggest that PPP can induce cell cycle arrest and apoptosis via the production of ROS and inhibition of PI3K/AKT signaling pathway, thereby suppressing the proliferation of prostate cancer cells.


Assuntos
Neoplasias da Próstata , Proteínas Proto-Oncogênicas c-akt , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Masculino , Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases/metabolismo , Podofilotoxina/análogos & derivados , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio
6.
J Assist Reprod Genet ; 39(3): 559-572, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35182265

RESUMO

OBJECTIVE: To compare the prevalence of chromosomal abnormalities detected in products of conception (POCs) between recurrent pregnancy loss and sporadic pregnancy loss. METHODS: A systematic search was performed in the PubMed and Embase databases from inception to December 31, 2020. Relevant studies analysing the association between the number of pregnancy losses and the incidence of chromosomal abnormalities were included. Independent data extraction was conducted and study quality was assessed. Meta-analyses were carried out to calculate odds ratios by using fixed- or random-effects models according to statistical homogeneity. RESULTS: A total of 8320 POCs in 19 studies were identified for the meta-analyses. The incidence of chromosomal abnormalities in sporadic pregnancy loss was significantly higher than that in recurrent pregnancy loss. In subgroup analyses, the following studies reported a high incidence of abnormal outcomes of sporadic pregnancy loss: studies with ≥ 300 samples, studies published before 2014, studies conducted in European and American countries, and studies with analyses using conventional karyotype techniques. Moreover, the incidence of chromosomal abnormalities in women with two pregnancy losses was significantly higher than that in women with three or more pregnancy losses. However, there was no difference in the distribution of abnormal types between sporadic and recurrent pregnancy loss or between two and three or more pregnancy losses. CONCLUSIONS: The prevalence of chromosomal abnormalities detected in POCs was lower in recurrent pregnancy loss than in sporadic pregnancy loss, and decreased with an increasing number of pregnancy losses.


Assuntos
Aborto Habitual , Aborto Habitual/epidemiologia , Aborto Habitual/genética , Aberrações Cromossômicas , Feminino , Humanos , Cariótipo , Cariotipagem , Gravidez
7.
J Cell Mol Med ; 24(21): 12464-12475, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32954681

RESUMO

NF-YA is considered as a crucial regulator for the maintenance of cancer stem cell (CSC) and involved in various types of malignant tumours. However, the exact function and molecular mechanisms of NF-YA in the progression of cervical cancer remains poorly understood. Here, the expression of NF-YA detected by immunohistochemistry was gradually increased from normal cervical tissues, to the high-grade squamous intraepithelial lesions, and then to cervical cancer tissues. NF-YA promoted the cell proliferation and tumorigenic properties of cervical cancer cells as well as tumorsphere formation and chemoresistance in vitro. The luciferase reporter assay combined with mutagenesis analyses and Western blotting showed that NF-YA trans-activated the expression of SOX2 in cervical cancer. Furthermore, quantitative chromatin immunoprecipitation (qChIP) and electrophoretic mobility shift assay (EMSA) confirmed that NF-YA protein directly bound to the CCAAT box region located upstream of the SOX2 promoter. Together, our data demonstrated that NF-YA was highly expressed in cervical cancer and promoted the cell proliferation, tumorigenicity and CSC characteristic by trans-activating the expression of SOX2.


Assuntos
Fator de Ligação a CCAAT/metabolismo , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição SOXB1/metabolismo , Neoplasias do Colo do Útero/metabolismo , Animais , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Separação Celular , Sobrevivência Celular , Feminino , Humanos , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Ativação Transcricional , Displasia do Colo do Útero/metabolismo
8.
Neurodegener Dis ; 20(5-6): 165-172, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34077945

RESUMO

INTRODUCTION: Idiopathic normal pressure hydrocephalus (iNPH) is one of the potentially reversible dementias. Early and accurate diagnosis is important for patients' prognosis. Emerging evidence shows fluid biomarkers are useful in diagnosis and pathophysiological research of iNPH. METHODS: Probable iNPH and Alzheimer's disease (AD) patients were recruited. Clinical diagnosis was performed according to international guidelines. CSF collection complied with a standard protocol. Commercial accessible ELISA kits were introduced for measurement of CSF t-tau, p-tau181, Aß42, and NfL. RESULTS: Twenty-seven iNPH, 27 AD, and 18 controls were included. The profiles of CSF t-tau, p-tau181, and t-tau/Aß42 in the iNPH and AD were significantly different (p < 0.0001). The profiles of CSF t-tau, p-tau181, and t-tau/Aß42 in the iNPH and control were not different (p > 0.05). Level of CSF Aß42 in iNPH was significantly lower than control (p < 0.0001) and also significantly higher than AD (p < 0.05). NfL level in iNPH and AD was increased, but its level in iNPH was significantly lower than that in AD (p = 0.005). NfL and t-tau level in the iNPH group was significantly correlated (coefficient = 0.649, p = 0.005), but not in AD (coefficient = 0.298, p = 0.157). CONCLUSION: Alzheimer's CSF biomarker profile of iNPH subjects showed moderately decreased Aß42 and normal t-tau, p-tau181, and t-tau/Aß42, which was distinguishable from AD. The different profiles and correlation of t-tau and NfL suggested different pathophysiology of AD and iNPH. t-tau was relatively an AD-specific neurodegenerative biomarker compared to NfL.

9.
Virus Genes ; 55(2): 248-252, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30600430

RESUMO

Porcine pegiviruses (PPgV) have been first discovered in serum samples from domestic pigs in Germany in 2016 and then in the USA in 2018. To date, there is no documentation with respect to the presence of PPgVs in domestic pigs in China. Herein, we attempted to determine the presence and prevalence of PPgV in China and its genetic characterization. In this study, 469 sera were tested and 34 (7.25%) were positive for PPgV. An ascending trend of the positive rate for PPgV was observed from suckling piglets (1.61%) to nursing piglets (1.85%), finishing pigs (6.56%), and sows (11.34%). The complete genome sequence of a representative strain of PPgV, PPgV_GDCH2017, and the complete E2 gene of 17 PPgV isolates discovered in this study was determined. Sequence analysis indicated that PPgV_GDCH2017 was highly related to other PPgVs with nucleotide and amino acid identities ranging from 87.3 to 97.4% and 94.6-99.3%, respectively, in the complete coding region. Phylogenetic analyses demonstrated that the PPgV_GDCH2017 discovered in this study was closely related to the PPgVs from the USA and clustered in the same genus with pegiviruses from other hosts. The topology of the phylogenetic tree based on the complete E2 gene was consistent with that based on the complete genome of PPgV. Further studies on pathogenicity and pathogenesis of PPgVs are needed.


Assuntos
Infecções por Flaviviridae/virologia , Flaviviridae/genética , Genoma Viral/genética , Doenças dos Suínos/genética , Animais , China , Flaviviridae/isolamento & purificação , Flaviviridae/patogenicidade , Infecções por Flaviviridae/genética , Alemanha , Filogenia , Suínos/virologia , Doenças dos Suínos/virologia , Estados Unidos , Sequenciamento Completo do Genoma
10.
Cell Biochem Funct ; 37(3): 193-202, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30917408

RESUMO

Hypoxic pulmonary arterial hypertension is characterized by elevated pulmonary vascular resistance and remodelling. Transforming growth factor-ß1 (TGF-ß1 ) is the master regulator in cellular response to hypoxia which can directly target lysyl oxidase (LOX). This study aimed to determine whether hypercapnia attenuates hypoxic pulmonary hypertension via regulating TGF-ß1 and LOX signalling. We found that exposure to hypercapnia ameliorated the increase in mean pulmonary artery pressure (mPAP) and ratio of right ventricle to left ventricle plus septum (RV/(LV + S)) induced by hypoxia but had no effect on mPAP and RV/(LV + S) in normoxia-exposed control. In addition, exposure to hypoxia upregulated the mRNA and protein levels of LOX and TGF-ß1 in rat PASMCs both in vivo and in vitro, but these effects were abrogated by concurrent exposure to hypercapnia. The downregulation of LOX in rat PASMCs induced by hypercapnia was reversed by the administration with TGF-ß1 , while TGF-ß1 knockdown repressed the upregulation of LOX in hypoxia-exposed rat PASMCs. In conclusion, hypoxia upregulates LOX and TGF-ß1 expression in PASMCs and contributes to pulmonary hypertension. Hypercapnia downregulates hypoxia-induced LOX expression and alleviates hypoxia-associated pulmonary hypertension via inhibiting TGF-ß1 signalling. SIGNIFICANCE OF THE STUDY: Hypoxia-induced upregulation of TGF-ß1 , PDGF, and HIF-1α plays a pivotal role in PAH, but molecular mechanism of how hypoxia regulates LOX expression is not clear. In the present study, we showed that mRNA and protein expression levels of LOX were substantially increased when TGF-ß1 was induced by hypoxia, and the effects were reversed by TGF-ß1 knockdown. Our study indicates that TGF-ß1 is implicated in the regulation of LOX.


Assuntos
Regulação para Baixo , Hipercapnia/metabolismo , Hipertensão Pulmonar/metabolismo , Proteína-Lisina 6-Oxidase/biossíntese , Transdução de Sinais , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Animais , Apoptose , Hipóxia Celular , Sobrevivência Celular , Células Cultivadas , Hipertensão Pulmonar/patologia , Masculino , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Proteína-Lisina 6-Oxidase/metabolismo , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo
11.
Can J Microbiol ; 65(11): 795-804, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31238002

RESUMO

A novel Klebsiella pneumoniae strain (BPBA052) capable of degrading 3-phenoxybenzoic acid (3-PBA) was isolated from soybean rhizosphere soil. The strain was obtained by screening after enrichment, isolation, and purification using 3-PBA as the sole carbon and energy source. It could degrade 96.37% of 3-PBA (100 mg/L) within 72 h, and its growth and 3-PBA degradation followed kinetics models of logistic growth (XBPBA052 = 0.0883 × e0.0947t / [1 - 0.0792 × (1 - 0.0883 × e0.0947t)]; µm = 0.0947 h-1, X0 = 0.0883, and Xm = 1.1145) and first-order degradation (CBPBA052 = 101.8194 × e-0.0403t, k = 0.0403, t1/2 = 17.22 h), respectively. Based on Box-Behnken response surface analysis, the optimal temperature, pH, and 3-PBA concentration for K. pneumoniae BPBA052 were 35.01 °C, 7.77, and 150 mg/L, respectively. Moreover, pyrethroid pesticides (PPs) (such as ß-cypermethrin, permethrin, bifenthrin, deltamethrin, and fenvalerate) and 3-PBA metabolites (including phenol, catechol, and protocatechuate) were efficiently utilized by BPBA052. We propose a novel microbial metabolic pathway for 3-PBA, based on metabolite identification; enzyme-degrading activity; and cloning of the phenol hydroxylase, catechol 1,2-dioxygenase, and protocatechuate 3,4-dioxygenase genes. This study provides a fundamental platform for further studies to reveal the mechanism of biodegradation of 3-BPA and show K. pneumoniae BPBA052 as a potential microbial resource for bioremediation of environments polluted with 3-PBA or PPs.


Assuntos
Benzoatos/metabolismo , Klebsiella pneumoniae/metabolismo , Praguicidas/metabolismo , Piretrinas/metabolismo , Benzoatos/química , Biodegradação Ambiental , Cinética , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Praguicidas/química , Fenóis/química , Fenóis/metabolismo , Piretrinas/química , Microbiologia do Solo
12.
Med Sci Monit ; 24: 427-437, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29356802

RESUMO

BACKGROUND The aim of this study was to evaluate the dispersal effects of 3,5-dicaffeoylquinic acid (3,5-DCQA) against the preformed biofilm of Aspergillus fumigatus and to investigate its potential mechanism. MATERIAL AND METHODS Aspergillus fumigatus biofilms of laboratory strain AF293 and clinical strain GXMU04 were generated in 24- or 96-well polystyrene microtiter plates in vitro. Crystal violet assay and XTT reduction assay were performed to evaluate the effects of 3,5-DCQA on biofilm biomass, extracellular matrix, and metabolic activity alteration of cells in biofilms. Real-time PCR was performed to quantify the expression of hydrophobin genes. The cytotoxicity of 3,5-DCQA on human erythrocytes was evaluated by a hemolytic assay. RESULTS The results indicated that 3,5-DCQA in subminimum inhibitory concentrations (256 to 1024 mg/L) elicited optimal A. fumigatus biofilm dispersion activity and improved the efficacy of VRC and AMB in minimal fungicidal concentrations (MFCs) to combat fungal cells embedded in biofilms. The results of scanning electron microscope (SEM) and confocal laser scanning microscopy (CLSM) revealed 3,5-DCQA facilitated the entry of antifungal agents into the A. fumigatus biofilm through eliminating the hydrophobic extracellular matrix (ECM) without affecting fungal growth. Real-time PCR indicated that 3,5-DCQA down-regulated the expression of hydrophobin genes. Hemolytic assay confirmed that 3,5-DCQA exhibited a low cytotoxicity against human erythrocytes. CONCLUSIONS Subminimum inhibitory concentrations of 3,5-DCQA can disperse A. fumigatus biofilm and enhance fungicidal efficacy of VRC and AMB through down-regulating expression of the hydrophobin genes. The study indicated the anti-biofilm potential of 3,5-DCQA for the management of A. fumigatus biofilm-associated infection.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/fisiologia , Biofilmes/efeitos dos fármacos , Ácido Clorogênico/análogos & derivados , Voriconazol/farmacologia , Antifúngicos/química , Aspergillus fumigatus/metabolismo , Aspergillus fumigatus/ultraestrutura , Biomassa , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/metabolismo , Ácido Clorogênico/química , Ácido Clorogênico/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Polissacarídeos/biossíntese
13.
J Comput Chem ; 37(20): 1907-13, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27282122

RESUMO

Recent experiments indicate that fullerene isomers outside the classical definition can also encapsulate metallic atoms or clusters to form endohedral metallofullerenes. Our systematic study using DFT calculations, suggests that many heptagon-including nonclassical trimetallic nitride template fullerenes are similar in stability to their classical counterparts, and that conversion between low-energy nonclassical and classical parent cages via Endo-Kroto insertion/extrusion of C2 units and Stone-Wales isomerization may facilitate the formation of endohedral trimetallic nitride fullerenes. Close structural connections are found between favored isomers of trimetallic nitride template fullerenes from C78 to C82 . It appears that the lower symmetry and local deformations associated with introduction of a heptagonal ring favor encapsulation of intrinsically less symmetrical mixed metal nitride clusters. © 2016 Wiley Periodicals, Inc.

14.
Chemphyschem ; 15(13): 2780-4, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25045089

RESUMO

Sc(2)S@C(84) has recently been detected but not structurally characterized.1 Density functional theory calculations on C(84) and Sc(2)S@C(84) show that the favored isomer of Sc(2)S@C84 shares the same parent cage as Sc(2)C2@C(84), whereas Sc(2)S@C(84):51383, which violates the isolated-pentagon rule, is the second lowest energy isomer with the widest HOMO-LUMO gap and shows high kinetic stability. The analysis shows that Sc(2)S@C(84):51575 is favored when the temperature exceeds 2,800 K and it can transform into the most favorable isomer Sc(2)S@C(84):51591. Molecular orbital analysis indicates that both Sc(2)S and Sc(2)C(2) formally transfer four electrons to the cage, and quantum theory of atoms in molecules analysis demonstrates that there is a covalent interaction between Sc(2)S and C(84):51591. The IR spectra of Sc(2)S@C(84) are provided to aid future structural identification.

15.
Physiol Plant ; 150(3): 397-411, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24032447

RESUMO

WRKY proteins are encoded by a large gene family and are linked to many biological processes across a range of plant species. The functions and underlying mechanisms of WRKY proteins have been investigated primarily in model plants such as Arabidopsis and rice. The roles of these transcription factors in non-model plants, including pepper and other Solanaceae, are poorly understood. Here, we characterize the expression and function of a subgroup IIe WRKY protein from pepper (Capsicum annuum), denoted as CaWRKY27. The protein localized to nuclei and activated the transcription of a reporter GUS gene construct driven by the 35S promoter that contained two copies of the W-box in its proximal upstream region. Inoculation of pepper cultivars with Ralstonia solanacearum induced the expression of CaWRKY27 transcript in 76a, a bacterial wilt-resistant pepper cultivar, whereas it downregulated the expression of CaWRKY27 transcript in Gui-1-3, a bacterial wilt-susceptible pepper cultivar. CaWRKY27 transcript levels were also increased by treatments with salicylic acid (SA), methyl jasmonate (MeJA) and ethephon (ETH). Transgenic tobacco plants overexpressing CaWRKY27 exhibited resistance to R. solanacearum infection compared to that of wild-type plants. This resistance was coupled with increased transcript levels in a number of marker genes, including hypersensitive response genes, and SA-, JA- and ET-associated genes. By contrast, virus-induced gene silencing (VIGS) of CaWRKY27 increased the susceptibility of pepper plants to R. solanacearum infection. These results suggest that CaWRKY27 acts as a positive regulator in tobacco resistance responses to R. solanacearum infection through modulation of SA-, JA- and ET-mediated signaling pathways.


Assuntos
Capsicum/genética , Regulação da Expressão Gênica de Plantas/genética , Nicotiana/genética , Proteínas de Plantas/genética , Ralstonia solanacearum/crescimento & desenvolvimento , Fatores de Transcrição/genética , Acetatos/farmacologia , Capsicum/metabolismo , Capsicum/microbiologia , Ciclopentanos/farmacologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Inativação Gênica , Interações Hospedeiro-Patógeno , Compostos Organofosforados/farmacologia , Oxilipinas/farmacologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Ralstonia solanacearum/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ácido Salicílico/farmacologia , Fatores de Tempo , Nicotiana/metabolismo , Nicotiana/microbiologia , Fatores de Transcrição/metabolismo
16.
Parasitol Res ; 113(7): 2629-39, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24816816

RESUMO

Allograft inflammatory factor-1 (AIF-1) plays an important role in various inflammatory conditions. Our previous study demonstrated that AIF-1 was over-expressed in the liver of BALB/c mice infected with Schistosoma japonicum and played significant role in the pathogenesis of schistosomiasis. The aim of this study was to focus on the effect of AIF-1 treatment on liver fibrosis and necrosis of BALB/c mice infected with S. japonicum. Seventy-two BALB/c mice were infected with cercariae of S. japonicum and then divided into three groups: AIF-1-treated group, saline-treated group, and control group. The vital signs, liver function, egg load, and hepatic pathological changes of the mice were assessed, and the levels of AIF-1 and TNF-α in the liver and spleen were measured at 5, 8, and 14 weeks postinfection. The treatment of AIF-1 on the mice infected with S. japonicum suppressed the expression of TNF-α and increased the effectiveness of AIF-1 in the liver and spleen at 14 weeks postinfection. Histopathological analysis and Masson trichrome staining for the liver tissues showed that the liver fibrosis and necrosis were alleviated previously compared with other infected mice at 14 weeks postinfection. The treatment of AIF-1 on the mice infected with S. japonicum can alleviate hepatic fibrosis and necrosis which indicate that AIF-1 use may prevent and cure the liver fibrosis.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação a DNA/farmacologia , Cirrose Hepática/tratamento farmacológico , Fígado/efeitos dos fármacos , Proteínas dos Microfilamentos/metabolismo , Esquistossomose Japônica/tratamento farmacológico , Animais , Proteínas de Ligação a DNA/genética , Feminino , Expressão Gênica , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/mortalidade , Cirrose Hepática/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Contagem de Ovos de Parasitas , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Schistosoma japonicum/efeitos dos fármacos , Schistosoma japonicum/crescimento & desenvolvimento , Schistosoma japonicum/patogenicidade , Esquistossomose Japônica/metabolismo , Esquistossomose Japônica/mortalidade , Esquistossomose Japônica/parasitologia , Baço/efeitos dos fármacos , Baço/metabolismo , Baço/patologia , Análise de Sobrevida , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
17.
J Hazard Mater ; 466: 133453, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38246062

RESUMO

Ciprofloxacin (CIP) is a prevalent environmental contaminant that poses a high risk of antibiotic resistance. High concentrations of antibiotics can lead to the development of resistant bacteria with high fitness costs, which often face a competitive disadvantage. However, it is unclear whether low-cost resistant bacteria formed by exposure to sub-MIC CIP in the environment can evolve competitive mechanisms against sensitive Escherichia coli (SEN) other than stronger resistance to CIP. Our study exposed E. coli to sub-MIC CIP levels, resulting in the development of CIP-resistant E. coli (CIPr). In antibiotic-free co-culture assays, CIPr outcompeted SEN. This indicates that CIPr is very likely to continue to develop and spread in antibiotic-free environments such as drinking water and affect human health. Further mechanism investigation revealed that bacterial membrane vesicles (BMVs) in CIPr, functioning as substance delivery couriers, mediated a cleavage effect on SEN. Proteomic analysis identified Entericidin B (EcnB) within CIPr-BMVs as a key factor in this competitive interaction. RT-qPCR analysis showed that the transcription of its negative regulator ompR/envZ was down-regulated. Moreover, EcnB plays a crucial role in the development of CIP resistance, and some resistance-related proteins and pathways have also been discovered. Metabolomics analysis highlighted the ability of CIPr-BMVs to acidify SEN, increasing the lytic efficiency of EcnB through cationization. Overall, our study reveals the importance of BMVs in mediating bacterial resistance and competition, suggesting that regulating BMVs production may be a new strategy for controlling the spread of drug-resistant bacteria.


Assuntos
Ciprofloxacina , Escherichia coli , Humanos , Ciprofloxacina/farmacologia , Escherichia coli/genética , Proteômica , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Bactérias
18.
Int J Biol Macromol ; 270(Pt 2): 132348, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750838

RESUMO

Gambogic acid is a natural compound with anticancer properties and is effective for many tumors. But its low water solubility and dose-dependent side effects limit its clinical application. This study aims to develop a novel drug delivery system for intratumoral delivery of gambogic acid. In our experimental study, we propose a new method for encapsulating gambogic acid nanoparticles using a manganese composite hyaluronic acid hydrogel as a carrier, designed for targeted drug delivery to tumors. The hydrogel delivery system is synthesized through the coordination of hyaluronic acid-dopamine (HA-DOPA) and manganese ions. The incorporation of manganese ions serves three purposes:1.To form cross-linked hydrogels, thereby improving the mechanical properties of HA-DOPA.2.To monitor the retention of hydrogels in vivo in real-time using magnetic resonance imaging (MRI).3.To activate the body's immune response. The experimental results show that the designed hydrogel has good biosafety, in vivo sustained release effect and imaging tracking ability. In the mouse CT26 model, the hydrogel drug-loaded group can better inhibit tumor growth. Further immunological analysis shows that the drug-loaded hydrogel group can stimulate the body's immune response, thereby better achieving anti-tumor effects. These findings indicate the potential of the developed manganese composite hyaluronic acid hydrogel as an effective and safe platform for intratumoral drug delivery. The amalgamation of biocompatibility, controlled drug release, and imaging prowess positions this system as a promising candidate for tumor treatment.


Assuntos
Ácido Hialurônico , Hidrogéis , Manganês , Nanopartículas , Xantonas , Ácido Hialurônico/química , Animais , Manganês/química , Xantonas/química , Xantonas/farmacologia , Xantonas/administração & dosagem , Camundongos , Nanopartículas/química , Hidrogéis/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Imageamento por Ressonância Magnética
19.
J Environ Sci (China) ; 25(10): 2065-71, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24494493

RESUMO

In order to investigate the CH4 and CO2 fluxes across the water-gas interface and identify their controlling factors, four diel field campaigns and one monthly sampling campaign during June 2010-May 2011 were carried out at a site near the Three Gorges Dam, China. The averaged CH4 and CO2 fluxes across the air-water interface from the site were much less than those reported from reservoirs in tropic and temperate regions, and from the natural river channels of the Yangtze River. CH4 Fluxes at the site were very low compared to most other reservoirs or natural lakes. One of the most important reasons may be due to the oxidation of CH4 in the water column owing to the great water depth and high DO in water in the Three Gorges Reservoir. The averaged monthly CH4 and CO2 fluxes at the site during the observation year were 0.05 mg/(m2 x hr) and 104.43 mg/(m2 x hr) respectively with the maximum occurred in July 2010. The monthly CO2 fluxes during the observation year were positively correlated to the surface water temperature, and negatively correlated to the air pressure and the surface water pH. The CO2 flux showed a positive correlation with DOC to some extent, although not significantly, which indicated that allochthonous organic C was a major source of CO2 and biogeochemical processes in this reservoir were C-limited. The significantly positive correlation between the reservoir outflow and the seasonal gas flux indicate the disturbance condition of the water body dominated the seasonal gas emission.


Assuntos
Dióxido de Carbono/química , Ritmo Circadiano , Metano/química , Rios/química , Estações do Ano , China , Fatores de Tempo
20.
Transl Neurosci ; 14(1): 20220271, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37588107

RESUMO

Background: Recent studies have highlighted that circular RNAs regulate cancer-related genes' expression by functioning as microRNA sponges in cancers. Herein, we investigated the function and molecular mechanism of circYIPF6 in glioma. Methods: 5-Ethynyl-2'-deoxyuridine assay, colony formation, and flow cytometry were performed to assess the proliferation and apoptosis of glioma cells. The levels of glycolytic metabolism were evaluated by measuring the glucose uptake and lactate production. The protein levels of Bax, Bcl2, GLUT1, LDHA, and PTBP1 were examined by western blot. The interplay between miR-760 and circYIPF6 or PTBP1 was confirmed by a dual-luciferase reporter. The effect of circYIPF6 silencing on the growth of glioma in vivo was determined by a xenograft experiment. Results: circYIPF6 was significantly upregulated in glioma. Knockdown of circYIPF6 suppressed glioma cell proliferation and glycolysis while promoting cell apoptosis. Mechanistic studies revealed that circYIPF6 targeted miR-760 and could abundantly sponge miR-760 to inhibit the expression of its downstream target gene PTBP1. Functional rescue experiments showed that both miR-760 inhibition and PTBP1 overexpression could attenuate the regulatory effect of circYIPF6 silencing on glioma cells. Furthermore, circYIPF6 knocking down effectively impeded glioma growth in vivo. Conclusion: These findings suggested that circYIPF6 participated in the proliferation, apoptosis, and glycolysis of glioma through the miR-760/PTBP1 axis.

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