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1.
Mol Ther ; 32(3): 766-782, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38273656

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic lethal disease in the absence of demonstrated efficacy for preventing progression. Although macrophage-mediated alveolitis is determined to participate in myofibrotic transition during disease development, the paradigm of continuous macrophage polarization is still under-explored due to lack of proper animal models. Here, by integrating 2.5 U/kg intratracheal Bleomycin administration and 10 Gy thorax irradiation at day 7, we generated a murine model with continuous alveolitis-mediated fibrosis, which mimics most of the clinical features of our involved IPF patients. In combination with data from scRNA-seq of patients and a murine IPF model, a decisive role of CCL2/CCR2 axis in driving M1 macrophage polarization was revealed, and M1 macrophage was further confirmed to boost alveolitis in leading myofibroblast activation. Multiple sticky-end tetrahedral framework nucleic acids conjunct with quadruple ccr2-siRNA (FNA-siCCR2) was synthesized in targeting M1 macrophages. FNA-siCCR2 successfully blocked macrophage accumulation in pulmonary parenchyma of the IPF murine model, thus preventing myofibroblast activation and leading to the disease remitting. Overall, our studies lay the groundwork to develop a novel IPF murine model, reveal M1 macrophages as potential therapeutic targets, and establish new treatment strategy by using FNA-siCCR2, which are highly relevant to clinical scenarios and translational research in the field of IPF.


Assuntos
Fibrose Pulmonar Idiopática , Macrófagos , Humanos , Camundongos , Animais , Modelos Animais de Doenças , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose , DNA , Bleomicina
2.
J Transl Med ; 22(1): 315, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539235

RESUMO

BACKGROUND: The treatment for colon adenocarcinoma (COAD) faces challenges in terms of immunotherapy effectiveness due to multiple factors. Because of the high tumor specificity and immunogenicity, neoantigen has been considered a pivotal target for cancer immunotherapy. Therefore, this study aims to identify and predict the potential tumor antigens of MUC somatic mutations (MUCmut) in COAD. METHODS: Three databases of TCGA, TIMER2.0, and cBioPortal were used for a detailed evaluation of the association between MUCmut and multi-factors like tumor mutation burden (TMB), microsatellite instability (MSI), prognosis, and the tumor microenvironment within the context of total 2242 COAD patients. Next, TSNAdb and the differential agretopicity index (DAI) were utilized to predict high-confidence neopeptides for MUCmut based on 531 COAD patients' genomic information. DAI was calculated by subtraction of its predicted HLA binding affinity of the MUCmut peptide from the corresponding wild-type peptide. RESULTS: The top six mutation frequencies (14 to 2.9%) were from MUC16, MUC17, MUC5B, MUC2, MUC4 and MUC6. COAD patients with MUC16 and MUC4 mutations had longer DFS and PFS. However, patients with MUC13 and MUC20 mutations had shorter OS. Patients with the mutation of MUC16, MUC5B, MUC2, MUC4, and MUC6 exhibited higher TMB and MSI. Moreover, these mutations from the MUC family were associated with the infiltration of diverse lymphocyte cells and the expression of immune checkpoint genes. Through TSNAdb 1.0/NetMHCpan v2.8, 452 single nucleotide variants (SNVs) of MUCmut peptides were identified. Moreover, through TSNAdb2.0/NetMHCpan v4.0, 57 SNVs, 1 Q-frame shift (TS), and 157 short insertions/deletions (INDELs) of MUCmut were identified. Finally, 10 high-confidence neopeptides of MUCmut were predicted by DAI. CONCLUSIONS: Together, our findings establish the immunogenicity and therapeutic potential of mutant MUC family-derived neoantigens. Through combining the tools of TSNAdb and DAI, a group of novel MUCmut neoantigens were identified as potential targets for immunotherapy.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Humanos , Mutação/genética , Antígenos de Neoplasias/metabolismo , Antígeno Ca-125/genética , Peptídeos/química , Microambiente Tumoral
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(3): 373-379, 2021 May.
Artigo em Zh | MEDLINE | ID: mdl-34018353

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a type of pulmonary disease that progresses acutely or slowly into irreversible pulmonary diseases, resulting in the end severe damages to patients' lung functions, as well as deaths. At present, the pathogenesis of pulmonary fibrosis is still not clear and there is no effective therapeutic measure available to control the progression of the disease. Research findings indicate that stem cells, being the origin of all cells of organisms, participate in the development of individuals at various stages and play an important role in repairing pulmonary tissue damage. Stem cells are attracting growing attention in the field of regenerative medicine, providing new ideas for treating IPF with transplanted stem cells. Herein, in order to better explore the potential applications of stem cell transplantation in treating IPF, we attempt to summarize preliminary studies of stem cell-mediated pulmonary remodeling after IPF, as well as cutting-edge clinical trials in stem cell-based IPF therapy.


Assuntos
Fibrose Pulmonar Idiopática , Transplante de Células-Tronco Mesenquimais , Humanos , Fibrose Pulmonar Idiopática/terapia , Pulmão , Cicatrização
4.
J Cell Biochem ; 119(2): 1368-1380, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28722813

RESUMO

The metastasis-associated lung adenocarcinoma transcription 1 (Malat1) is a long non-coding RNA (lncRNA), exerts oncogenic role in multiple cancers, including hepatocellular carcinoma (HCC). This study was aimed to investigate its posttranscriptional regulation in HCC cells. RT-PCR was performed to monitor the expression levels of Malat1 in normal liver and HCC cell lines. The expression of Malat1, microRNA (miR)-195, and epidermal growth factor receptor (EGFR) in HepG2 and MHCC97 cells was respectively or synchronously altered by transfection. Then the changes in cell viability, apoptotic cell rate, cell cycle distribution, migration, and invasion were respectively assessed. As a result, we found that Malat1 was highly expressed in HCC cell lines when compared to normal liver cells. Malat1 silence suppressed HCC cells viability, migration and invasion, induced apoptosis, and arrested more cells in G0/G1 phase. Malat1 acted as a circular endogenous RNA (ceRNA) for miR-195. Malat1 silence could not suppress HCC cell growth and motility when miR-195 was knocked down. EGFR was a direct target of miR-195. miR-195 overexpression could not suppress HCC cell growth and motility when the 3'UTR site of EGFR was overexpressed. Furthermore, Malat1 silence blocked the activation of PI3K/AKT and JAK/STAT pathways, while EGFR overexpression activated them. Our study demonstrates Malat1-miR-195-EGFR axis plays a critical role in HCC cells which provided a better understanding of Malat1 in HCC.


Assuntos
Carcinoma Hepatocelular/genética , Receptores ErbB/genética , Técnicas de Silenciamento de Genes , Neoplasias Hepáticas/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos
5.
BMC Microbiol ; 14: 197, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-25124936

RESUMO

BACKGROUND: Biosurfactants (BS) are amphiphilic compounds produced by microbes, either on the cell surface or secreted extracellularly. BS exhibit strong antimicrobial and anti-adhesive properties, making them good candidates for applications used to combat infections. In this study, our goal was to assess the in vitro antimicrobial, anti-adhesive and anti-biofilm abilities of BS produced by Lactobacillus jensenii and Lactobacillus rhamnosus against clinical Multidrug Resistant (MDR) strains of Acinetobacter baumannii, Escherichia coli, and Staphylococcus aureus (MRSA). Cell-bound BS from both L. jensenii and L. rhamnosus were extracted and isolated. The surface activities of crude BS samples were evaluated using an oil spreading assay. The antimicrobial, anti-adhesive and anti-biofilm activities of both BS against the above mentioned MDR pathogens were determined. RESULTS: Surface activities for both BS ranged from 6.25 to 25 mg/ml with clear zones observed between 7 and 11 cm. BS of both L. jensenii and L. rhamnosus showed antimicrobial activities against A. baumannii, E. coli and S. aureus at 25-50 mg/ml. Anti-adhesive and anti-biofilm activities were also observed for the aforementioned pathogens between 25 and 50 mg/ml. Finally, analysis by electron microscope indicated that the BS caused membrane damage for A. baumannii and pronounced cell wall damage in S. aureus. CONCLUSION: Our results indicate that BS isolated from two Lactobacilli strains has antibacterial properties against MDR strains of A. baumannii, E. coli and MRSA. Both BS also displayed anti-adhesive and anti-biofilm abilities against A. baumannii, E. coli and S. aureus. Together, these capabilities may open up possibilities for BS as an alternative therapeutic approach for the prevention and/or treatment of hospital-acquired infections.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Lactobacillus/química , Staphylococcus aureus/efeitos dos fármacos , Tensoativos/farmacologia , Acinetobacter baumannii/fisiologia , Antibacterianos/isolamento & purificação , Aderência Bacteriana/efeitos dos fármacos , Escherichia coli/fisiologia , Staphylococcus aureus/fisiologia , Tensoativos/isolamento & purificação
6.
Exp Biol Med (Maywood) ; 246(1): 97-105, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33172301

RESUMO

Previous studies demonstrated that mitochondrial fission arguments the stemness of bone marrow-derived mesenchymal stem cells (BMSCs). Because mitophagy is critical in removing damaged or surplus mitochondrial fragments and maintaining mitochondrial integrity, the present study was undertaken to test the hypothesis that mitophagy is involved in mitochondrial fission-enhanced stemness of BMSCs. Primary cultures of rat BMSCs were treated with tyrphostin A9 (TA9, a potent inducer of mitochondrial fission) to increase mitochondrial fission, which was accompanied by enhanced mitophagy as defined by increased co-staining of MitoTracker Green for mitochondria and LysoTracker Deep Red for lysosomes, as well as the increased co-localization of autophagy markers (LC3B, P62) and mitochondrial marker (Tom20). A mitochondrial uncoupler, carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (FCCP) was used to promote mitophagy, which was confirmed by an increased co-localization of mitochondrial and lysosome biomarkers. The argumentation of mitophagy was associated with enhanced stemness of BMSCs as defined by increased expression of stemness markers Oct4 and Sox2, and enhanced induction of BMSCs to adipocytes or osteocytes. Conversely, transfection of BMSCs with siRNA targeting mitophagy-essential genes Pink1/Prkn led to diminished stemness of the stem cells, as defined by depressed stemness markers. Importantly, concomitant promotion of mitochondrial fission and inhibition of mitophagy suppressed the stemness of BMSCs. These results thus demonstrate that mitophagy is critically involved in mitochondrial fission promotion of the stemness of BMSCs.


Assuntos
Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Mitofagia , Animais , Inativação Gênica , Dinâmica Mitocondrial , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ratos Sprague-Dawley , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
7.
Cell Prolif ; 54(8): e13084, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34170049

RESUMO

OBJECTIVES: Autoimmune diseases are a heterogeneous group of diseases which lose the immunological tolerance to self-antigens. It is well recognized that irregularly provoked T cells participate in the pathological immune responses. As a novel nanomaterial with promising applications, tetrahedral framework nucleic acid (TFNA) nanostructure was found to have immune regulatory effects on T cells in this study. MATERIALS AND METHODS: To verify the successful fabrication of TFNA, the morphology of TFNA was observed by atomic force microscopy (AFM) and dynamic light scattering. The regulatory effect of TFNA was evaluated by flow cytometry after cocultured with CD3+ T cells isolated from healthy donors. Moreover, the associated signaling pathways were investigated. Finally, we verified our results on the T cells from patients with neuromyelitis optica spectrum disorder (NMOSD), which is a typical autoimmune disease induced by T cells. RESULTS: We revealed the alternative regulatory functions of TFNA in human primary T cells with steady status via the JNK signaling pathway. Moreover, by inhibiting both JNK and ERK phosphorylation, TFNA exhibited significant suppressive effects on IFNγ secretion from provoking T cells without affecting TNF secretion. Similar immune regulatory effects of TFNA were also observed in autoreactive T cells from patients with NMOSD. CONCLUSIONS: Overall, our results revealed a potential application of TFNA in regulating the adaptive immune system, as well as shed a light on the treatment of T cell-mediated autoimmune diseases.


Assuntos
Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ácidos Nucleicos/farmacologia , Adulto , Células Cultivadas , Ciclosporina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Interferon gama/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Pessoa de Meia-Idade , Nanoestruturas/química , Neuromielite Óptica/metabolismo , Neuromielite Óptica/patologia , Ácidos Nucleicos/síntese química , Ácidos Nucleicos/química , Fosforilação/efeitos dos fármacos , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
8.
J Exp Med ; 196(11): 1523-8, 2002 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-12461087

RESUMO

Recognition of human erythrocytes by Plasmodium species depends in part on Region II of the Duffy binding-like family of parasite ligands, which includes BA erythrocyte binding ligand (BAEBL) of P. falciparum. In previous studies of BAEBL from two clones, Dd2/Nm from Vietnam and E12 from Papua New Guinea (PNG), it was found that BAEBL bound different erythrocyte receptors. Because of variation in binding specificity, we studied the sequence and erythrocyte binding specificity of Region II of BAEBL in P. falciparum clones from different parts of the world. We observed five nucleotide substitutions leading to five amino acid changes and five polymorphisms in Region II of BAEBL in parasites from both PNG and other parts of the world. We expressed four of the polymorphisms on COS cells and determined their binding to enzyme-treated erythrocytes and to Gerbich-negative erythrocytes. We also performed erythrocyte-binding assay using the native protein from radiolabeled culture supernatant. Both assays demonstrated that each of the four polymorphisms in the parasite ligand, BAEBL, bound to a different receptor on erythrocytes. These results suggest that P. falciparum has evolved multiple invasion pathways dependent on polymorphisms in the BAEBL ligand.


Assuntos
Proteínas de Transporte/genética , Eritrócitos/metabolismo , Proteínas de Protozoários/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação , Células COS , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Proteínas de Membrana , Dados de Sequência Molecular , Papua Nova Guiné , Polimorfismo Genético , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo
9.
Cardiovasc Res ; 116(1): 114-126, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30854566

RESUMO

AIMS: Sialylation is up-regulated during the development of cardiac hypertrophy. Sialyltransferase7A (Siat7A) mRNA is consistently over-expressed in the hypertrophic left ventricle of hypertensive rats independently of genetic background. The aims of this study were: (i) to detect the Siat7A protein levels and its roles in the pathological cardiomyocyte hypertrophy; (ii) to elucidate the effect of sialylation mediated by Siat7A on the transforming-growth-factor-ß-activated kinase (TAK1) expression and activity in cardiomyocyte hypertrophy; and (iii) to clarify hypoxia-inducible factor 1 (HIF-1) expression was regulated by Siat7A and transactivated TAK1 expression in cardiomyocyte hypertrophy. METHODS AND RESULTS: Siat7A protein level was increased in hypertrophic cardiomyocytes of human and rats subjected to chronic infusion of angiotensin II (ANG II). Delivery of adeno-associated viral (AAV9) bearing shRNA against rat Siat7A into the left ventricular wall inhibited ventricular hypertrophy. Cardiac-specific Siat7A overexpression via intravenous injection of an AAV9 vector encoding Siat7A under the cardiac troponin T (cTNT) promoter aggravated cardiac hypertrophy in ANG II-treated rats. In vitro, Siat7A knockdown inhibited the induction of Sialyl-Tn (sTn) antigen and cardiomyocyte hypertrophy stimulated by ANG II. Mechanistically, ANG II induced the activation of TAK1-nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signalling in parallel to up-regulation of Siat7A in hypertrophic cardiomyocytes. Siat7A knockdown inhibited activation of TAK1-NF-κB pathway. Interestingly, HIF-1α expression was increased in cardiomyocytes stimulated by ANG II but decreased after Siat7A knockdown. HIF-1α knockdown efficiently decreased TAK1 expression. ChIP and luciferase assays showed that HIF-1α transactivated the TAK1 promoter region (nt -1285 to -1274 bp) in the cardiomyocytes following ANG II stimulus. CONCLUSION: Siat7A was up-regulated in hypertrophic myocardium and promoted cardiomyocyte hypertrophy via activation of the HIF-1α-TAK1-NF-κB pathway.


Assuntos
Angiotensina II , Hipertrofia Ventricular Esquerda/enzimologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Miócitos Cardíacos/enzimologia , Sialiltransferases/metabolismo , Função Ventricular Esquerda , Remodelação Ventricular , Animais , Linhagem Celular , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica , Humanos , Hipertrofia Ventricular Esquerda/induzido quimicamente , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , MAP Quinase Quinase Quinases/genética , Masculino , Miócitos Cardíacos/patologia , Interferência de RNA , Ratos Wistar , Sialiltransferases/genética , Transdução de Sinais
10.
Exp Biol Med (Maywood) ; 244(1): 64-72, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30614257

RESUMO

IMPACT STATEMENT: How to maintain the stemness of bone marrow mesenchymal stem cells (BMSCs) in cultures is a long-standing question. The present study found that mitochondrial dynamics affects the stemness of BMSCs in cultures and the retaining of mitochondrial fission enhances the stemness of BMSCs. This work thus provides a novel insight into strategic approaches to maintain the stemness of BMSCs in cultures in relation to the clinical application of bone-marrow stem cells.


Assuntos
Células-Tronco Mesenquimais/citologia , Dinâmica Mitocondrial , Animais , Diferenciação Celular , Dinaminas/metabolismo , Citometria de Fluxo , Molécula 1 de Adesão Intercelular/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Quinazolinonas/farmacologia , Ratos Sprague-Dawley , Nicho de Células-Tronco , Antígenos Thy-1/metabolismo , Tirfostinas/farmacologia
11.
BMC Mol Biol ; 9: 90, 2008 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-18928538

RESUMO

BACKGROUND: RNA transfection into dendritic cells (DCs) is widely used to achieve antigen expression as well as to modify DC properties. CD40L is expressed by activated T cells and interacts with CD40 receptors expressed on the surface of the DCs leading to Th1 polarization. Previous studies demonstrated that ectopic CD40L expression via DNA transfection into DCs can activate the CD40 receptor signal transduction cascade. In contrast to previous reports, this study demonstrates that the same effect can be achieved when RNA encoding CD40L is electroporated into DCs as evidenced by secretion of IL-12. To achieve higher levels of IL-12 secretion, a systematic approach involving modification of coding and noncoding regions was implemented to optimize protein expression in the DCs for the purpose of increasing IL-12 secretion. RESULTS: Site-directed mutagenesis of each of the first five in-frame methionine codons in the CD40L coding sequence demonstrated that DCs expressing a truncated CD40L protein initiated from the second methionine codon secreted the highest levels of IL-12. In addition, a post-transcriptional method of capping was utilized for final modification of the CD40L RNA. This method enzymatically creates a type I cap structure identical to that found in most eukaryotic mRNAs, in contrast to the type 0 cap incorporated using the conventional co-transcriptional capping reaction. CONCLUSION: The combination of knocking out the first initiation methionine and post-transcriptional capping of the CD40L RNA allowed for approximately a one log increase in IL-12 levels by the transfected DCs. We believe this is a first report describing improved protein expression of post-transcriptionally capped RNA in DCs. The post-transcriptional capping which allows generation of a type I cap may have broad utility for optimization of protein expression from RNA in DCs and other cell types.


Assuntos
Ligante de CD40/genética , Células Dendríticas/metabolismo , Interleucina-12/biossíntese , Processamento Pós-Transcricional do RNA , Regiões 5' não Traduzidas/química , Sequência de Aminoácidos , Sequência de Bases , Antígenos CD40/fisiologia , Ligante de CD40/biossíntese , Células Cultivadas , Códon de Iniciação/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Capuzes de RNA/metabolismo , Regulação para Cima
12.
J Gastroenterol Hepatol ; 23(8 Pt 1): 1228-34, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18637057

RESUMO

BACKGROUND AND AIM: Several models for significant fibrosis or cirrhosis have been introduced for hepatitis C, but are seldom for hepatitis B. The present study retrospectively evaluates the relationship between ultrasonography, blood tests, and fibrosis stage, and constructs a model for predicting compensated cirrhosis. METHODS: A total of 653 patients with chronic hepatitis B who underwent liver biopsies, ultrasonographic scanning, and routine blood tests were retrospectively analyzed. The patients were divided into the model set and validation set. Blood tests and ultrasonographic indexes were analyzed statistically. An ultrasonographic scoring system consisting of liver parenchyma, gallbladder, hepatic vessel, and splenomegaly was introduced. RESULTS: There were significant differences between cirrhosis and other fibrosis stages in ultrasonographic indexes of liver parenchyma, gallbladder, hepatic vessel, and splenomegaly. Ultrasonographic scores were significantly different between F4 and other fibrosis, and significantly correlated with fibrosis stage. Apart from alanine aminotransferase and alkaline phosphatase, blood tests and patients' age were correlated with fibrosis, and were significantly different between patients with and without cirrhosis. The model for cirrhosis indexes consisting of ultrasonographic score, patient's age, and variables, including platelet, albumin, and bilirubin predicted cirrhosis with area under receiver-operator curve of 0.907 in the model set and 0.849 in the validation set. Using proper cut-off values, nearly 81% patients could be accurately assessed for the absence or presence of cirrhosis. CONCLUSION: The model consisting of ultrasonographic score, patients' age, blood variables of platelet, albumin, and bilirubin can identify hepatitis B cirrhosis with a high degree of accuracy. The application of this model would greatly reduce the number of biopsies.


Assuntos
Hepatite B/sangue , Cirrose Hepática/diagnóstico , Fígado/patologia , Adolescente , Adulto , Biópsia , Criança , Feminino , Hepatite B/complicações , Humanos , Fígado/diagnóstico por imagem , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Valor Preditivo dos Testes , Estudos Retrospectivos , Ultrassonografia , Adulto Jovem
13.
Cardiovasc Toxicol ; 18(4): 365-373, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29396798

RESUMO

Cytochrome c oxidase (CCO) is a copper-dependent enzyme of mitochondrial respiratory chain. In pressure overload-induced cardiac hypertrophy, copper level and CCO activity are both depressed, along with disturbance in mitochondrial fusion and fission dynamics. Copper repletion leads to recovery of CCO activity and normalized mitochondrial dynamics. The present study was undertaken to define the link between CCO activity and mitochondrial dynamic changes. Primary cultures of neonatal rat cardiomyocytes were treated with phenylephrine to induce cell hypertrophy. Hypertrophic cardiomyocytes were then treated with copper to reverse hypertrophy. In the hypertrophic cardiomyocytes, CCO activity was depressed and mitochondrial fusion was suppressed. Upon copper repletion, CCO activity was recovered and mitochondrial fusion was reestablished. Depression of CCO activity by siRNA targeting CCO assembly homolog 17 (COX17), a copper chaperone for CCO, led to fragmentation of mitochondria, which was not recoverable by copper supplementation. This study thus demonstrates that copper-dependent CCO is critical for mitochondrial fusion in the regression of cardiomyocyte hypertrophy.


Assuntos
Cardiomegalia/tratamento farmacológico , Sulfato de Cobre/farmacologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias Cardíacas/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Fenilefrina/toxicidade , Animais , Cardiomegalia/induzido quimicamente , Cardiomegalia/enzimologia , Cardiomegalia/patologia , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Células Cultivadas , Proteínas de Transporte de Cobre , Mitocôndrias Cardíacas/enzimologia , Mitocôndrias Cardíacas/patologia , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Cultura Primária de Células , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
14.
Biochem Biophys Res Commun ; 364(4): 748-54, 2007 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-17977514

RESUMO

The glycosylphosphatidylinositol (GPI) anchors of Plasmodium falciparum are indispensable for parasite survival since merozoite surface proteins-1, -2, -4, -5, and -10, crucial for erythrocyte invasion, are GPI-anchored. Therefore, the GPI biosynthetic pathway can offer potential targets for novel anti-malarial drugs. Here, we characterized the putative P. falciparum PIG-B gene (PfPIGB) that encodes mannosyltransferase-III of GPI biosynthesis. PfPIGB mRNA is transcribed in a developmental stage specific manner. A protein corresponding to the expected size of PfPIG-B is expressed by the parasite and is localized in the endoplasmic reticulum. Treatment of parasites with PfPIG-B specific siRNA caused reduction in GPI synthesis, affecting the PIG-B specific GPI intermediate. These data demonstrate that PfPIG-B is functional and encodes mannosyltransferase-III of the parasite GPI biosynthesis. The parasite PfPIG-B is novel in that its signature sequence HKEHKI is unique and is only partially conserved as compared to HKEXRF signature motif of mammalian PIG-B enzymes.


Assuntos
Manosiltransferases/genética , Manosiltransferases/metabolismo , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Animais , Sequência de Bases , Dados de Sequência Molecular , Especificidade de Órgãos , Distribuição Tecidual
15.
Zhonghua Yi Xue Za Zhi ; 87(26): 1840-3, 2007 Jul 10.
Artigo em Zh | MEDLINE | ID: mdl-17922996

RESUMO

OBJECTIVE: To investigate the relapse of patients with chronic hepatitis B (CHB) undergoing first and repeated recombinant interferon-alpha (rIFN-alpha) therapy during long-term follow up. METHOD: Five hundred and twenty three patients with chronic hepatitis B including 403 hepatitis B e-antigen (HBeAg) positive patients and 120 HBeAg negative ones were treated with 5MU recombinant interferon-alpha 1b (rIFN-alpha1b) subcutaneously thrice weekly for 6 - 25 (median 10) months. For each patient, serum alanine aminotransferase (ALT) was measured biochemically and serum HBV DNA level was detected by fluorescent-quantitative PCR, HBeAg with enzyme immunoassay every 1 - 3 month during therapy and every 3 - 6 month during the follow up period. Some of the individuals who relapsed during the follow-up period were treated with interferon-alpha repeatedly. RESULTS: Ratios of early response to interferon-alpha were similar in HBeAg positive patients (55.8%, 225/403), and HBeAg negative patients (64.2%, 77/120) at the end of naive treatment (chi(2) = 2.633, P = 0.105). 39.4% (119/302) of early responders relapsed during 39 +/- 22-month follow up, and relapse rates in HBeAg negative group (55.8%, 43/77) were higher than those in HBeAg positive group (33.8%, 76/225) at the end of follow up (chi(2) = 19.335, P = 0.000). Divided the follow-up period into six fragments as 1 - 12 months, 13 - 24 months, 25 - 36 months, 37 - 48 months, 48 - 60 months and > or = 61 months, we found that the differences of relapse incidence were significant (chi(2) = 73.518, df = 5, P = 0.000), and accumulative relapse rates were significant too (chi(2) = 32.167, df = 5, P = 0.000) in all follow-up periods. Constituent ratios of HBeAg in relapsed patients of every follow-up period were similar. 57 relapsed individuals (25 in HBeAg positive group and 32 in HBeAg negative group) were retreated with interferon-alpha, and complete response were achieved in all cases at the end of repeated therapy. The relapse rates in HBeAg positive group (52.0%, 13/25) were higher than in HBeAg negative group (21.9%, 7/32) during the follow-up period after the end of retreatment (chi(2) = 5.592, P = 0.018). CONCLUSION: Rates of early response to interferon-alpha therapy were similar in HBeAg positive and HBeAg negative patients at the end of nave treatment, and relapse rates in HBeAg negative group were higher than in HBeAg positive group during long term follow-up. Combined response was achieved in all relapse cases received repeated interferon-alpha therapy at the end of retreatment. The relapse rates in HBeAg positive group were higher than in HBeAg negative group during the follow-up period after repeated therapy.


Assuntos
Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Interferon Tipo I/uso terapêutico , Adulto , Alanina Transaminase/sangue , Antivirais/uso terapêutico , DNA Viral/sangue , DNA Viral/genética , Feminino , Seguimentos , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Reação em Cadeia da Polimerase , Proteínas Recombinantes , Recidiva , Fatores de Tempo , Resultado do Tratamento
16.
Zhonghua Gan Zang Bing Za Zhi ; 15(6): 422-4, 2007 Jun.
Artigo em Zh | MEDLINE | ID: mdl-17594805

RESUMO

OBJECTIVE: To investigate the relationship of virological breakthrough and production of neutralizing anti-interferon antibody (NAb) in chronic hepatitis B patients treated with recombinant interferon-alpha (rIFN-alpha). METHOD: Four hundred eighty-five patients with histological proven chronic hepatitis B were treated with 5 MU recombinant interferon-alpha 1b (rIFN-alpha1b) thrice weekly for 6-37 months (median 10). Serum HBV DNA, HBeAg and NAb levels of the patients were detected by fluorescent-quantitative PCR, enzymoimmunoassay and antiviral neutralizing biological assay respectively during the therapy. RESULTS: Virological breakthrough occurred in 66 patients (13.6%), and NAb was found in 98 patients (20.2%) of the total 485 patients. The rate of NAb positivity was higher in patients with viral breakthrough than those without it (68.2%, 45/66, vs 12.6%, 53/419, chi(2)=109.06, P < 0.01), and viral breakthrough occurred more in patients with positive NAb than with negative NAb (45.9%, 45/98, vs 5.4%, 21/387, chi(2)=109.06, P < 0.01). The time of the viral breakthrough occurrence and the time of NAb production had a significant correlation (P < 0.01). The occurrence of viral breakthrough was also influenced by the age of patients (P < 0.05) and HBeAg status (P < 0.01) before they were treated. CONCLUSION: Viral breakthrough occurred in 13.6% of our 485 chronic hepatitis B patients treated with recombinant interferon-alpha. Their viral breakthrough and production of NAb production had a significant correlation.


Assuntos
Anticorpos Anti-Hepatite B/biossíntese , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Interferon Tipo I/uso terapêutico , Adulto , Anticorpos Neutralizantes/biossíntese , Feminino , Vírus da Hepatite B/imunologia , Humanos , Masculino , Proteínas Recombinantes , Adulto Jovem
17.
Exp Ther Med ; 14(4): 3088-3092, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28928803

RESUMO

This study examined the application of 64-slice spiral double-low computed tomography (CT) to evaluate the degree of coronary artery stenosis. We examined 45 patients with coronary heart disease by 64-slice spiral double-low CT and coronary angiography (CAG) to determine CT accuracy in evaluating coronary artery stenosis. Imaging analysis from 64-slice spiral double-low CT identified 199 segments with coronary stenosis from 45 patients, including 46 segments with mild stenosis, 38 with moderate stenosis and 115 with severe stenosis or artery occlusion. CT analysis agreed with CAG on the identification of the degree of stenosis in 122 segments, with an overall accuracy of 61.3%. The accuracy for serious stenosis or occlusion was the highest at 69.6%. We also found a strong correlation between coronary plaque compositions and the degree of stenosis. Correspondence analysis showed that the presence of soft plaques closely correlated with severe stenosis, whereas mixed plaques closely correlated with moderate stenosis. Overall, 64-slice spiral double-low CT imaging can effectively assess the degree of coronary artery stenosis in patients with coronary heart disease and accurately detect plaque composition. Thus, 64-slice spiral double-low CT imaging can predict the risk of coronary heart disease and the degree of coronary artery stenosis, which is helpful for early diagnosis and treatment of coronary heart disease.

18.
Gene ; 371(1): 68-74, 2006 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-16426772

RESUMO

Alzheimer's disease (AD) is the most common cause of dementia in humans. A pathological hallmark in the brain of an AD patient is extracellular amyloid plaques formed by accumulated beta-amyloid protein (Abeta), a metabolic product of amyloid precursor protein (APP). Studies have revealed a strong genetic linkage in the early-onset familial form (<60 years old) of AD. For example, some mutant APPs are transmitted dominantly and are segregated with inheritance of early onset AD. These mutants facilitate Abeta production. The "Swedish" mutations (APP(SW)) and the "London" mutation (APP(LON)) are examples of these mutants. Selective silencing of these mutant alleles holds therapeutic promise for AD. Here we show that the expression of the mutant APPs was selectively inhibited by RNA interference. The best selectivity was obtained when the mismatches were centrally placed in the antisense strand of small interfering RNAs. Introducing an additional mismatch in the antisense strand may improve the selectivity. The addition of a G at 5' end of the antisense strand may enhance the efficacy of gene silencing by RNA interference. Our results illustrate the guiding principles for selection of targeted sequences to achieve allele-specific silencing. The sequences that are effective to silence APP(SW) and APP(LON) as identified in this study may be useful in both in vivo and in vitro studies to investigate the pathophysiological role of APP(SW) and APP(LON) in AD development.


Assuntos
Alelos , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Mutação , Interferência de RNA , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/biossíntese , Animais , Células CHO , Cricetinae , Cricetulus , Expressão Gênica , Células HeLa , Humanos
19.
Zhonghua Gan Zang Bing Za Zhi ; 13(1): 24-6, 2005 Jan.
Artigo em Zh | MEDLINE | ID: mdl-15670486

RESUMO

OBJECTIVE: To study the causes of poorer antiviral response to neutralizing anti-interferon-alpha antibodies (NA) in male chronic hepatitis B patients treated with recombinant interferon-alpha (rIFN-alpha). METHODS: Two hundred sixty-nine patients (198 males and 71 females) with histologically proven chronic hepatitis B were treated with 5 MU recombinant interferon-alpha 1b (rIFN-alpha 1b) subcutaneously thrice weekly for 6-37 (median 10.0) months. For each patient, serum HBV DNA levels were detected with fluorescent-quantitative PCR, HBeAg with enzymoimmunoassay, and NA with an antiviral neutralizing biological assay during therapy. RESULTS: NA was found in 70 (35.4%) of the 198 males and in 15 (21.1%) of the 71 females during treatment (x2 = 4.894, P = 0.027). At the end of treatment combined-response was achieved in 21 (24.7%) of the 85 NA-positive patients and in 100 (54.3%) of the 184 NA-negative cases (x2 = 20.642). Stratification analysis by NA showed that combined-response rate was significantly lower in males than in females (18.6%, 13/70 vs. 53.3%, 8/15, x2 = 8.024) among NA-positive patients while it was similar in males and in females (50.8%, 65/128, vs. 62.5%, 35/56, x2 = 2.156) among NA-negative patients. In stratification analysis by gender, it was significantly lower in NA-positive patients than in NA-negative ones (18.6%, 13/70 vs. 53.3%, 8/15, x2 = 8.024) among males but there was no significant difference between combined-response rates among females. CONCLUSION: The poorer antiviral response to recombinant interferon-alpha in male chronic hepatitis B patients than in female patients is related to the neutralizing anti-interferon antibodies.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Interferon Tipo I/uso terapêutico , Anticorpos/sangue , Antivirais/imunologia , DNA Viral/sangue , Feminino , Humanos , Interferon Tipo I/imunologia , Masculino , Testes de Neutralização , Proteínas Recombinantes , Fatores Sexuais , Resultado do Tratamento
20.
Chin Med J (Engl) ; 115(3): 422-4, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11940380

RESUMO

OBJECTIVE: To investigate the compositions of Th1/Th2/Th3 cells in chronic hepatitis B virus (HBV)-infected individuals by determining the expression of interleukin-4 (IL-4), inetrferon-gamma (IFN-gamma), and transform growth factor-beta (TGF-beta) in single CD4(+) T cells isolated from peripheral blood mononuclear cells (PBMCs) and the role of polarized Th cell populations in chronic HBV-infection was discussed. METHODS: PBMCs from chronically infected HBV individuals were isolated, stimulated by PMA/Ionomycin/Monensin, and IL-4, IFN-gamma and TGF-beta production by CD4(+) T cells was determined by using fluorescence activated cell sorter (FACS) analysis. RESULTS: The percentage of IFN-gamma-producing T cells, IL-4-producing T cells and TGF-beta-producing T cells ranged from 2.3% - 18.6%, 1.1% - 8.7% and 0.7% - 7.1% respectively in CD4(+) T cells from non-infected individuals. Most of CD4(+) T cells from PBMCs in chronically infected HBV individuals were Th0 cells. The proportion of Th1 cells increased significantly with hepatic inflammatory activity, and in the active period of chronic hepatitis B infection were higher than those in the non-active period (P < 0.05). Th2 cell percentage in CD4(+) T cells from HBV-infected individuals did not differ significantly (P > 0.05), but were higher than that from controls (P < 0.05). Th3 cell percentage in CD4(+) T cells from asymptomatic carrier (AsC) group was higher than that in the chronic hepatitis B (CHB) and control groups (P < 0.05). CONCLUSIONS: Th1 phenotype cytokines were positively correlated with hepatic inflammatory activity in chronic hepatitis B and Th2 cells may be associated with the persistence of HBV infection. Th3 cells cooperating with Th2 cells can negatively regulate immune responses and may be associated with the immune tolerant state of chronic HBV infection.


Assuntos
Hepatite B Crônica/patologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T CD4-Positivos/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/metabolismo , Humanos , Interferon gama/biossíntese , Interleucina-4/biossíntese , Células Th1/imunologia , Células Th2/imunologia , Fator de Crescimento Transformador beta/biossíntese
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