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1.
Proc Natl Acad Sci U S A ; 121(20): e2319115121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38709931

RESUMO

The endosomal sorting complexes required for transport (ESCRTs) are responsible for membrane remodeling in many cellular processes, such as multivesicular body biogenesis, viral budding, and cytokinetic abscission. ESCRT-III, the most abundant ESCRT subunit, assembles into flat spirals as the primed state, essential to initiate membrane invagination. However, the three-dimensional architecture of ESCRT-III flat spirals remained vague for decades due to highly curved filaments with a small diameter and a single preferred orientation on the membrane. Here, we unveiled that yeast Snf7, a component of ESCRT-III, forms flat spirals on the lipid monolayers using cryogenic electron microscopy. We developed a geometry-constrained Euler angle-assigned reconstruction strategy and obtained moderate-resolution structures of Snf7 flat spirals with varying curvatures. Our analyses showed that Snf7 subunits recline on the membrane with N-terminal motifs α0 as anchors, adopt an open state with fused α2/3 helices, and bend α2/3 gradually from the outer to inner parts of flat spirals. In all, we provide the orientation and conformations of ESCRT-III flat spirals on the membrane and unveil the underlying assembly mechanism, which will serve as the initial step in understanding how ESCRTs drive membrane abscission.


Assuntos
Microscopia Crioeletrônica , Complexos Endossomais de Distribuição Requeridos para Transporte , Proteínas de Saccharomyces cerevisiae , Membrana Celular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/ultraestrutura
2.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35177473

RESUMO

Researchers commonly anneal metals, alloys, and semiconductors to repair defects and improve microstructures via recrystallization. Theoretical studies indicate that simulated annealing on biological macromolecules helps predict the final structures with minimum free energy. Experimental validation of this homogenizing effect and further exploration of its applications are fascinating scientific questions that remain elusive. Here, we chose the apo-state 70S ribosome from Escherichia coli as a model, wherein the 30S subunit undergoes a thermally driven intersubunit rotation and exhibits substantial structural flexibility as well as distinct free energy. We experimentally demonstrate that annealing at a fast cooling rate enhances the 70S ribosome homogeneity and improves local resolution on the 30S subunit. After annealing, the 70S ribosome is in a nonrotated state with respect to corresponding intermediate structures in unannealed or heated ribosomes. Manifold-based analysis further indicates that the annealed 70S ribosome takes a narrow conformational distribution and exhibits a minimum-energy state in the free-energy landscape. Our experimental results offer a facile yet robust approach to enhance protein stability, which is ideal for high-resolution cryogenic electron microscopy. Beyond structure determination, annealing shows great potential for synchronizing proteins on a single-molecule level and can be extended to study protein folding and explore conformational and energy landscapes.


Assuntos
Conformação Proteica , Proteínas Ribossômicas/ultraestrutura , Ribossomos/fisiologia , Microscopia Crioeletrônica , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , RNA Ribossômico/metabolismo , RNA Ribossômico/ultraestrutura , Proteínas Ribossômicas/metabolismo , Ribossomos/ultraestrutura
3.
Cancer Immunol Immunother ; 71(6): 1295-1311, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34652523

RESUMO

The tumor immune microenvironment plays essential roles in regulating inflammation, angiogenesis, immune modulation, and sensitivity to therapies. Here, we developed a powerful prognostic signature with immune-related lncRNAs (irlncRNAs) in lung adenocarcinoma (LUAD). We obtained differentially expressed irlncRNAs by intersecting the transcriptome dataset for The Cancer Genome Atlas (TCGA)-LUAD cohort and the ImmLnc database. A rank-based algorithm was applied to select top-ranking altered irlncRNA pairs for the model construction. We built a prognostic signature of 33 irlncRNA pairs comprising 40 unique irlncRNAs in the TCGA-LUAD cohort (training set). The immune signature significantly dichotomized LUAD patients into high- and low-risk groups regarding overall survival, which is likewise independently predictive of prognosis (hazard ratio = 3.580, 95% confidence interval = 2.451-5.229, P < 0.001). A nomogram with a C-index of 0.79 demonstrates the superior prognostic accuracy of the signature. The prognostic accuracy of the signature of 33 irlncRNA pairs was validated using the GSE31210 dataset (validation set) from the Gene Expression Omnibus database. Immune cell infiltration was calculated using ESTIMATE, CIBERSORT, and MCP-count methodologies. The low-risk group exhibited high immune cell infiltration, high mutation burden, high expression of CTLA4 and human leukocyte antigen genes, and low expression of mismatch repair genes, which predicted response to immunotherapy. Interestingly, pRRophetic analysis demonstrated that the high-risk group possessed reverse characteristics was sensitive to chemotherapy. The established immune signature shows marked clinical and translational potential for predicting prognosis, tumor immunogenicity, and therapeutic response in LUAD.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , RNA Longo não Codificante , Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Humanos , Imunoterapia , Pulmão/patologia , Neoplasias Pulmonares/patologia , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Microambiente Tumoral/genética
4.
J Transl Med ; 19(1): 374, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34461934

RESUMO

BACKGROUND: Ubiquitin-conjugating enzyme E2T (UBE2T) acts as an oncogene in various types of cancer. However, the mechanisms behind its oncogenic role remain unclear in lung cancer. This study aims to explore the function and clinical relevance of UBE2T in lung cancer. METHODS: Lentiviral vectors were used to mediate UBE2T depletion or overexpress UBE2T in lung cancer cells. CCK8 analysis and western blotting were performed to investigate the effects of UBE2T on proliferation, autophagy, and relevant signaling pathways. To exploit the clinical significance of UBE2T, we performed immunohistochemistry staining with an anti-UBE2T antibody on 131 NSCLC samples. Moreover, we downloaded the human lung adenocarcinoma (LUAD) dataset from The Cancer Atlas Project (TCGA). Lasso Cox regression model was adopted to establish a prognostic model with UBE2T-correlated autophagy genes. RESULTS: We found that UBE2T stimulated proliferation and autophagy, and silencing this gene abolished autophagy in lung cancer cells. As suggested by Gene set enrichment analysis, we observed that UBE2T downregulated p53 levels in A549 cells and vice versa. Blockade of p53 counteracted the inhibitory effects of UBE2T depletion on autophagy. Meanwhile, the AMPK/mTOR signaling pathway was activated during UBE2T-mediated autophagy, suggesting that UBE2T promotes autophagy via the p53/AMPK/mTOR pathway. Interestingly, UBE2T overexpression increased cisplatin-trigged autophagy and led to cisplatin resistance of A549 cells, whereas inhibiting autophagy reversed drug resistance. However, no association was observed between UEB2T and overall survival in a population of 131 resectable NSCLC patients. Therefore, we developed and validated a multiple gene signature by considering UBE2T and its relevance in autophagy in lung cancer. The risk score derived from the prognostic signature significantly stratified LUAD patients into low- and high-risk groups with different overall survival. The risk score might independently predict prognosis. Interestingly, nomogram and decision curve analysis demonstrated that the signature's prognostic accuracy culminated while combined with clinical features. Finally, the risk score showed great potential in predicting clinical chemosensitivity. CONCLUSIONS: We found that UBE2T upregulates autophagy in NSCLC cells by activating the p53/AMPK/mTOR signaling pathway. The clinical predicting ability of UBE2T in LUAD can be improved by considering the autophagy-regulatory role of UBE2T.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Serina-Treonina Quinases TOR/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Proteínas Quinases Ativadas por AMP , Adenocarcinoma de Pulmão/genética , Autofagia , Humanos , Neoplasias Pulmonares/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Proteína Supressora de Tumor p53/genética , Enzimas de Conjugação de Ubiquitina/genética
5.
J Biol Chem ; 294(8): 2880-2891, 2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30587574

RESUMO

Accumulating evidence indicates that a wide range of E3 ubiquitin ligases are involved in the development of many human diseases. Searching for small-molecule modulators of these E3 ubiquitin ligases is emerging as a promising drug discovery strategy. Here, we report the development of a cell-based high-throughput screening method to identify modulators of E3 ubiquitin ligases by integrating the ubiquitin-reference technique (URT), based on a fusion protein of ubiquitin located between a protein of interest and a reference protein moiety, with a Dual-Luciferase system. Using this method, we screened for small-molecule modulators of SMAD ubiquitin regulatory factor 1 (SMURF1), which belongs to the NEDD4 family of E3 ubiquitin ligases and is an attractive therapeutic target because of its roles in tumorigenesis. Using RAS homolog family member B (RHOB) as a SMURF1 substrate in this screen, we identified a potent SMURF1 inhibitor and confirmed that it also blocks SMURF1-dependent degradation of SMAD family member 1 (SMAD1) and RHOA. An in vitro auto-ubiquitination assay indicated that this compound inhibits both SMURF1 and SMURF2 activities, indicating that it may be an antagonist of the catalytic activity of the HECT domain in SMURF1/2. Moreover, cell functional assays revealed that this compound effectively inhibits protrusive activity in HEK293T cells and blocks transforming growth factor ß (TGFß)-induced epithelial-mesenchymal transition (EMT) in MDCK cells, similar to the effects on these processes caused by SMURF1 loss. In summary, the screening approach presented here may have great practical potential for identifying modulators of E3 ubiquitin ligases.


Assuntos
Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina/metabolismo , Animais , Cães , Células HEK293 , Humanos , Células Madin Darby de Rim Canino , Transdução de Sinais , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
6.
J Cell Physiol ; 235(9): 6043-6057, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32052446

RESUMO

N6-methyladenosine (m6 A) RNA modification can alter gene expression and function by regulating RNA splicing, stability, translocation, and translation. Deregulation of m6 A has been involved in various types of cancer. However, its implications in non-small-cell lung cancer (NSCLC) are mostly unknown. This posttranscriptional modification is dynamically and reversibly mediated by different regulators, including methyltransferase, demethylases, and m6 A binding proteins. In this study, we comprehensively investigated the contributions and prognostic values of 13 common m6 A RNA modification regulators using The Cancer Genome Atlas database. We found that the expression levels of most of the studied genes were significantly altered in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). Using consensus clustering, the gene-expression profiles of 13 m6 A regulators could classify patients with LUAD into two subgroups with significantly distinct clinical outcomes, but not the LUSC cohort or the combination of the two cohorts. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and gene set enrichment analysis were applied to explore differential signaling pathways and cellular processes between the two LUAD subgroups. Moreover, we found that this gene-expression signature could better predict prognosis in the late-stage (III + IV) than in the early-stage (I + II) LUAD. Finally, we developed an optimal prognostic gene signature by using the least absolute shrinkage and selection operator Cox regression algorithm and compute risk score. In conclusion, our study unveiled the implication of m6 A RNA modification regulators in NSCLC and identified the m6 A gene expression classifiers for predicting the prognosis of NSCLC.


Assuntos
Adenosina/análogos & derivados , Carcinoma Pulmonar de Células não Pequenas/genética , Metilação de DNA/genética , RNA/genética , Adenosina/genética , Adenosina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Metiltransferases/genética , Pessoa de Meia-Idade , Prognóstico
7.
J Cell Biochem ; 120(10): 18094-18103, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31144382

RESUMO

The aim of our study is to construct the competing endogenous RNA (ceRNA) network of head and neck squamous cell carcinoma (HNSCC) and identify key long noncoding RNAs (lncRNAs) to predict prognosis. The genes whose expression were differentially in HNSCC and normal tissues were explored by the Cancer Genome Atlas database. The ceRNA network was constructed by the Cytoscape software. The lncRNAs which could estimate the overall survival were explored from Cox proportional hazards regression. There are 1997, 589, and 82 mRNAs, lncRNAs, and miRNAs whose expression were statistically significant different, respectively. Then, the network between miRNA and mRNA or miRNA and lncRNA was constructed by miRcode, miRDB, TargetScan, and miRanda. Five mRNAs, 10 lncRNAs, and 3 miRNAs were associated with overall survival. Then, 11-lncRNAs were found to be prognostic factors. Therefore, our research analyzed the potential signature of novel 11-lncRNA as candidate prognostic biomarker from the ceRNA network for patients with HNSCC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , RNA Longo não Codificante/genética , Idoso , Carcinoma de Células Escamosas/diagnóstico , Biologia Computacional/métodos , Feminino , Ontologia Genética , Redes Reguladoras de Genes , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Análise de Sobrevida
8.
EMBO Rep ; 18(10): 1801-1816, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28808113

RESUMO

The regulation of inflammation is pivotal for preventing the development or reoccurrence of multiple sclerosis (MS). A biased ratio of high-M1 versus low-M2 polarized microglia is a major pathological feature of MS Here, using microarray screening, we identify the long noncoding RNA (lncRNA) GAS5 as an epigenetic regulator of microglial polarization. Gain- and loss-of-function studies reveal that GAS5 suppresses microglial M2 polarization. Interference with GAS5 in transplanted microglia attenuates the progression of experimental autoimmune encephalomyelitis (EAE) and promotes remyelination in a lysolecithin-induced demyelination model. In agreement, higher levels of GAS5 are found in amoeboid-shaped microglia in MS patients. Further, functional studies demonstrate that GAS5 suppresses transcription of TRF4, a key factor controlling M2 macrophage polarization, by recruiting the polycomb repressive complex 2 (PRC2), thereby inhibiting M2 polarization. Thus, GAS5 may be a promising target for the treatment of demyelinating diseases.


Assuntos
Microglia/fisiologia , Esclerose Múltipla/fisiopatologia , RNA Longo não Codificante/genética , Diferenciação Celular , Doenças Desmielinizantes/fisiopatologia , Encefalomielite Autoimune Experimental , Epigênese Genética , Regulação da Expressão Gênica , Humanos , Inflamação , Macrófagos , Esclerose Múltipla/genética , RNA Longo não Codificante/metabolismo
9.
J Pharmacol Sci ; 139(4): 340-345, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30871871

RESUMO

Aralia echinocaulis is used for the treatment of rheumatoid arthritis by Tujia Minority in China. A previous study demonstrated that A. echinocaulis had a significant anti-arthritic effect on adjuvant arthritis (AA) rats in vivo. However, it remains unclear whether A. echinocaulis can induce the apoptosis of fibroblast-like synoviocytes (FLS) from AA rats and the underlying mechanism is unknown. In this paper, CCK-8 assay, Hoechst staining and flow cytometry were used to evaluate the apoptotic effect of an A. echinocaulis ethanol extract (AEE) on AA FLS. Western blotting analysis was performed to measure the protein expression levels of Bcl-2, Bax, cleaved caspase-3, Akt, p-Akt, and Hif-1α. The results revealed that AEE could inhibit FLS proliferation in a dose and time-dependent manner. After treatment with AEE, AA FLS displayed the classical apoptotic morphology, and the apoptosis rates were significantly increased. Furthermore, we found that AEE increased the protein levels of Bax, cleaved caspase 3, and decreased the protein levels of Bcl-2, Hif-1α and p-Akt, without affecting total Akt levels. Collectively, these results suggested that the apoptosis inducing effect of AEE on AA FLS was related to the regulation of the expression of apoptosis-related proteins and the inhibition of the Akt/Hif-1α signaling pathway.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/genética , Aralia/química , Artrite Experimental/genética , Artrite Experimental/patologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sinoviócitos/patologia , Animais , Caspase 3/genética , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Ratos Sprague-Dawley , Fatores de Tempo
10.
Anal Chem ; 90(15): 8936-8945, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29953204

RESUMO

A surface plasmon resonance (SPR) biosensor-based active ingredients recognition system (SPR-AIRS) was developed, validated, and applied to screen signal transducer and activator of transcription 3 (STAT3) ligands. First, features of the screening system were investigated in four aspects: (1) specificity of the STAT3-immobilized chip, it shows that the chip could be applied to screen STAT3 ligands from complex mixture; (2) linearity and limit of detection (LOD) of the system, the minimum recovery cycle number was determined as 5 cycles; (3) saturability of the chip, the results indicate that it is necessary to select a proper concentration based on the compound's Kd value; (4) robustness of the system, it indicates that inactive compounds in the matrix could not interfere with active compounds in the process of screening. Next, SPR-AIRS was applied to screen STAT3 ligands from medicinal herbs. Nine candidate compounds were fished out. Then SPR assay and molecular docking were performed to verify the interplay between STAT3 and candidate compounds. Apoptosis assay and luciferase report assay were performed to investigate the drug effect of candidate compounds on STAT3 activity. Western blot results indicated that neobaicalein and polydatin could inhibit the phosphorylation of STAT3. As far as we know, this is the first time that neobaicalein and polydatin are reported as effective STAT3 ligands. In a conclusion, we have systemically demonstrated the feasibility of SPR biosensor-based screening method applying to complex drug systems, and our findings suggest that SPR-AIRS could be a sensitive and effective solution for the discovery of active compounds from a complex matrix.


Assuntos
Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Fator de Transcrição STAT3/metabolismo , Ressonância de Plasmônio de Superfície/métodos , Apoptose/efeitos dos fármacos , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Células Hep G2 , Humanos , Proteínas Imobilizadas/metabolismo , Ligantes , Células MCF-7 , Simulação de Acoplamento Molecular
12.
J Neurosci ; 36(35): 9253-66, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27581464

RESUMO

UNLABELLED: T-helper 17 (Th17) cells play an important role in the pathogenesis of multiple sclerosis (MS), an autoimmune demyelinating disease that affects the CNS. In the present study, MicroRNA sequencing (miRNA-seq) was performed in mouse Th0 and Th17 cells to determine the critical miRNAs that are related to Th17 differentiation. We found that miR-30a was significantly downregulated during mouse Th17 differentiation. In addition, the level of miR-30a in CD4(+) T cells from peripheral blood of MS patients and experimental autoimmune encephalomyelitis (EAE) animal models was also decreased and inversely correlated with the expression of interleukin 17a, the canonical cytokine of Th17 cells. Moreover, overexpression of miR-30a inhibited Th17 differentiation and prevented the full development of EAE, whereas interference of miR-30a promoted Th17 differentiation. Mechanism studies showed that miR-30a reduced IRF4 expression by specifically binding with the 3'-untranslated region. Through screening of 640 different Food and Drug Administration (FDA)-approved drugs, we found that disulfiram and diphenhydramine hydrochloride were effective candidates for inhibiting Th17 differentiation and ameliorating EAE development through upregulating miR-30a. To our knowledge, the present work is not only the first miRNA-seq study focusing on Th17 differentiation, but also the first chemical screening for FDA-approved drugs that inhibit Th17 differentiation through regulating miRNA expression. SIGNIFICANCE STATEMENT: The present work is the first miRNA sequencing (miRNA-seq) study focusing on T-helper 17 (Th17) differentiation. By miRNA deep sequencing, we found that miR-30a was downregulated during Th17 differentiation. miR-30a was also decreased in CD4(+) T cells from multiple sclerosis patients and experimental autoimmune encephalomyelitis (EAE) mice. miR-30a reduced IRF4 expression by specific binding with the 3'-untranslated region and thus suppressed Th17 differentiation and prevented the full development of EAE. Interestingly, by performing a chemical screen with Food and Drug Administration-approved small-molecule drugs, we found that disulfiram and diphenhydramine upregulated miR-30a and suppressed Th17-associated autoimmune demyelination.


Assuntos
Difenidramina/farmacologia , Dissulfiram/farmacologia , Encefalomielite Autoimune Experimental/metabolismo , Interleucina-17/metabolismo , MicroRNAs/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/prevenção & controle , Feminino , Células HEK293 , Humanos , Fatores Reguladores de Interferon/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Proteolipídica de Mielina/toxicidade , Glicoproteína Mielina-Oligodendrócito/toxicidade , Fragmentos de Peptídeos/toxicidade , Estatísticas não Paramétricas , Transfecção
13.
Pancreatology ; 16(5): 733-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27324074

RESUMO

BACKGROUND/OBJECTIVES: Pulmonary apoptosis is an important pathogenic mechanism of acute lung injury induced by many factors. This study aims to investigate whether the caspase inhibitor zVAD-fmk has a protective effect against lung injury in the severe acute pancreatitis model (SAP) in rats. METHODS: Seventy-two Sprague-Dawley rats were randomly divided into Sham, SAP, and SAP + zVAD-fmk groups. The SAP model was established by injection of 5% sodium taurocholate into the pancreatic duct. Animals were sacrificed at 3 h, 6 h, 12 h, and 24 h after operation and then HE staining analysis was performed to assess the lung injury. ELISA was used to detect the activity of myeloperoxidase (MPO) and the concentrations of tumor necrosis factor α (TNF-α) and interleukin 1ß (IL-1ß). Western blotting was used to detect the expression of cleaved caspase-3 in the lung tissues. RESULTS: Rats in SAP group showed obvious lung injury through pathologic examination. Pretreatment with zVAD-fmk significantly inhibited a post-SAP increase in the activation of MPO, TNF-α, IL-1ß, and caspase-3, and decreased lung injury induced by SAP as determined by the pathologic score. CONCLUSION: Our results suggest that apoptosis plays an important role in acute pancreatitis-associated lung injury (APALI), and inhibition of caspase activity may represent a new therapeutic approach for the treatment of APALI.


Assuntos
Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/prevenção & controle , Clorometilcetonas de Aminoácidos/uso terapêutico , Apoptose/efeitos dos fármacos , Inibidores de Caspase/uso terapêutico , Inflamação/etiologia , Inflamação/prevenção & controle , Pancreatite/complicações , Lesão Pulmonar Aguda/patologia , Amilases/sangue , Animais , Caspase 3/biossíntese , Interleucina-1beta/antagonistas & inibidores , Masculino , Ductos Pancreáticos/patologia , Pancreatite/induzido quimicamente , Pancreatite/patologia , Ratos , Ratos Sprague-Dawley , Ácido Taurocólico , Fator de Necrose Tumoral alfa/antagonistas & inibidores
14.
Glia ; 63(4): 684-98, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25530119

RESUMO

Differentiation of oligodendrocyte precursor cells (OPCs) is a prerequisite for both developmental myelination and adult remyelination in the central nervous system. The molecular mechanisms underlying OPC differentiation remain largely unknown. Here, we show that the thirty-kDa HIV-1 Tat interacting protein (TIP30) is a negative regulator in oligodendrocyte development. The TIP30(-/-) mice displayed an increased myelin protein level at postnatal day 14 and 21. By using a primary OPC culture system, we demonstrated that overexpression of TIP30 dramatically inhibited the stage progression of differentiating OPCs, while knockdown of TIP30 enhanced the differentiation of oligodendroglial cells remarkably. Moreover, overexpression of TIP30 was found to sequester the transcription factor Olig1 in the cytoplasm and weaken its nuclear translocation due to the interaction between TIP30 and Olig1, whereas knockdown of TIP30 led to more Olig1 localized in the nucleus in the initiation stage during OPC differentiation. In the cuprizone-induced demyelination model, there was a dramatic increase in NG2-expressing cells with nuclear location of Olig1 in the corpus callosum during remyelination. In contrast, within chronic demyelinated lesions in multiple sclerosis, TIP30 was abnormally expressed in NG2-expressing cells, and few nuclear Olig1 was observed in these cells. Taken together, our findings suggest that TIP30 plays a negative regulatory role in oligodendroglial differentiation.


Assuntos
Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Citoplasma/metabolismo , Oligodendroglia/citologia , Proteínas Repressoras/metabolismo , Células-Tronco/citologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Animais Recém-Nascidos , Antígenos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores/metabolismo , Técnicas de Cultura de Células , Núcleo Celular/metabolismo , Corpo Caloso/citologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Bainha de Mielina/metabolismo , Fibras Nervosas Mielinizadas/metabolismo , Oligodendroglia/metabolismo , Oligodendroglia/fisiologia , Proteoglicanas/metabolismo , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética
15.
Mod Pathol ; 28(1): 37-47, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25059573

RESUMO

Dedifferentiated liposarcoma represents a form of liposarcoma composed of a non-lipogenic sarcoma associated with well-differentiated liposarcoma. The prognostic significance of histological grading of the dedifferentiated component remains to be elucidated due to vague grading criteria employed in previous studies. Molecular markers of tumor behavior, including amplification levels of murine double minute-2 (MDM2) and cyclin-dependent kinase-4 (CDK4) genes, have been explored in a limited number of cases. Here we investigate whether 'Fédération Nationale des Centres de Lutte Contre le Cancer' (FNCLCC) grade and MDM2 gene amplification levels have prognostic value in dedifferentiated liposarcoma in terms of local recurrence and disease-specific survival. Fifty cases were retrieved, reviewed and FNCLCC grade was scored for the dedifferentiated component. Testing for MDM2 gene amplification was performed by fluorescence in situ hybridization. Amplification was categorized as high level (≥20 copies) and as low level (<20 copies). Follow-up data was obtained through chart review. Log-rank test and Cox proportional hazard models were used to determine the effect of grade and level of MDM2 amplification on outcomes. Our series includes 50 patients (male n=28, female n=22) with an average age of 63 years (range, 28-88) and a median follow-up of 28 months (range, 2-120). Tumors were graded as grade 1 (6%), grade 2 (58%), and grade 3 (36%). When adjusted for age, sex, site, tumor size, and margin status, grade 3 patients had a higher recurrence rate than grades 1 and 2 (HR=2.07, 95% CI: 1.24, 7.62; P=0.015). Patients with high-level MDM2 amplification had higher recurrence rate on univariate analysis (P=0.028), but not on multivariate analysis (HR=1.69, 95% CI: 0.73, 3.94; P=0.221). FNCLCC grade 3 dedifferentiation confers a worse prognosis in dedifferentiated liposarcoma in terms of local recurrence. MDM2 amplification level remains a useful diagnostic tool in dedifferentiated liposarcoma, but has no prognostic value in terms of local recurrence.


Assuntos
Lipossarcoma/genética , Lipossarcoma/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Proteínas Proto-Oncogênicas c-mdm2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Amplificação de Genes , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Lipossarcoma/mortalidade , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos
16.
Acta Odontol Scand ; 73(8): 595-601, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25644205

RESUMO

BACKGROUND: Gallic acid (GA) has been shown to inhibit demineralization and enhance remineralization of enamel; however, GA solution is highly acidic. This study was to investigate the stability of GA solutions at various pH and to examine the resultant effects on enamel demineralization. METHODS: The stability of GA in H2O or in phosphate buffer at pH 5.5, pH 7.0 and pH 10.0 was evaluated qualitatively by ultraviolet absorption spectra and quantified by high performance liquid chromatography with diode array detection (HPLC-DAD). Then, bovine enamel blocks were subjected to a pH-cycling regime of 12 cycles. Each cycle included 5 min applications with one of the following treatments: 1 g/L NaF (positive control), 4 g/L GA in H2O or buffered at pH 5.5, pH 7.0 and pH 10.0 and buffers without GA at the same pH (negative control), followed by a 60 min application with pH 5.0 acidic buffers and a 5 min application with neutral buffers. The acidic buffers were analysed for dissolved calcium. RESULTS: GA was stable in pure water and acidic condition, but was unstable in neutral and alkaline conditions, in which ultraviolet spectra changed and HPLC-DAD analysis revealed that most of the GA was degraded. All the GA groups significantly inhibited demineralization (p < 0.05) and there was no significant difference of the inhibition efficacy among different GA groups (p > 0.05). CONCLUSIONS: GA could inhibit enamel demineralization and the inhibition effect is not influenced by pH. GA could be a useful source as an anti-cariogenic agent for broad practical application.


Assuntos
Cariostáticos/uso terapêutico , Esmalte Dentário/efeitos dos fármacos , Ácido Gálico/uso terapêutico , Desmineralização do Dente/prevenção & controle , Animais , Soluções Tampão , Cálcio/análise , Bovinos , Cromatografia Líquida de Alta Pressão , Esmalte Dentário/química , Concentração de Íons de Hidrogênio , Fosfatos/química , Fluoreto de Sódio/uso terapêutico , Espectrofotometria Ultravioleta , Remineralização Dentária , Água/química
17.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(11): 1361-6, 2015 Nov.
Artigo em Zh | MEDLINE | ID: mdl-26775486

RESUMO

OBJECTIVE: To explore the effect of Tanshinone II A on severe acute pancreatitis (SAP) lung injury (ALI) rats and its possible mechanism. METHODS: SD rats were injected with sodium taurocholate to induce SAP group, and then intervened with sodium tanshinone II A sulfonate ( STS group). Simultaneously a sham-operation group (SO group) was set up. There were 24 rats in each group. The survival state and wet-to-dry weight ratio of lung tissues were observed. Activities of myeloperoxidase (MPO) in lung were determined by MPO reagent kit. Pathologic changes of lung tissues were determined by Hofbuaer method. Expression levels of three cytokines, TNF-alpha, IL-1beta, and intercellular cell adhesion molecule-1 (ICAM-1) were detected by ELISA. RESULTS: The survival state of rats in the SAP group was deteriorated. The wet-to-dry weight ratio, MPO activities, pathologic changes in lung tissues, and expression levels of TNF-alpha, IL-1beta, and ICAM-1 increased significantly more in the SAP group than in the SO group (P < 0.05). Compared with those in the SAP group, the survival state of rats in the STS group was improved; the wet-to-dry weight ratio, MPO activities, pathologic changes in lung tissues, and expression levels of TNF-alpha, IL-1beta, and ICAM-1 obviously decreased in the STS group (P < 0.05). CONCLUSION: Tanshinone II A had remarkable effect on SPA LI rats, which might be associated with changing cytokines levels and attenuating infiltration of lung inflammatory cells.


Assuntos
Abietanos/farmacologia , Lesão Pulmonar Aguda/tratamento farmacológico , Citocinas/metabolismo , Pancreatite/tratamento farmacológico , Abietanos/uso terapêutico , Animais , Molécula 1 de Adesão Intercelular , Interleucina-1beta , Pulmão , Peroxidase , Ratos , Ratos Sprague-Dawley , Ácido Taurocólico , Fator de Necrose Tumoral alfa
18.
Genet Med ; 16(12): 881-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24922459

RESUMO

PURPOSE: We sought to characterize the natural history of vascular Ehlers-Danlos syndrome in individuals with heterozygous COL3A1 mutations. METHODS: We reviewed clinical records for details of vascular, bowel, and organ complications in 1,231 individuals (630 index cases and 601 relatives). RESULTS: Missense and splice-site mutations accounted for more than 90% of the 572 alterations that we had identified in COL3A1. Median survival was 51 years but was influenced by gender (lower in men) and by the type of mutation. CONCLUSION: Although vascular Ehlers-Danlos syndrome appears to be genetically homogeneous, allelic heterogeneity is marked, and the natural history varies with gender and type of mutation in COL3A1. These findings indicate that when counseling families, confirmation of the presence of a COL3A1 mutation and its nature can help evaluate the risks of complications. These data are also important ingredients in both the selection and allocation of individuals to appropriate arms in clinical trials to assess the effects of interventions.


Assuntos
Colágeno Tipo III/genética , Análise Mutacional de DNA , Síndrome de Ehlers-Danlos/genética , Síndrome de Ehlers-Danlos/mortalidade , Mutação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Criança , Feminino , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Splicing de RNA , Resultado do Tratamento , Adulto Jovem
19.
Pancreatology ; 14(2): 87-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24650959

RESUMO

BACKGROUND AND AIMS: Refractory chronic pancreatitis has been proposed as a challenge for endoscopists following routine single plastic stenting. However, data on the efficacy and safety of further endoscopic stenting are still controversial. The current systematic review aimed to assess the efficacy and safety of placement of fully covered self-expandable metal stent (FCSEMS) and multiple plastic stents. METHODS: Databases including MEDLINE, EMBASE, the Cochrane Library, CBM, CNKI, VIP, and WANFANG Database were used to search relevant trials. Published studies were assessed by using well-defined inclusion and exclusion criteria. The process was independently performed by two investigators. RESULTS: A total of 5 studies provided data of 80 patients. Forest plots and publication bias were not carried out because few studies were relevant and screened studies were all case series. The technical success rate was 100% both in placement of FCSEMS and multiple plastic stents. The functional success rate after placement of FCSEMS was 100%, followed by multiple plastic stents (94.7%). Complications occurred 26.2% after FCSEMS placement, which was not described in detail in multiple plastic stents. The stent migration rate was 8.2% for FCSEMS and 10.5% for multiple plastic stents. Reintervention rate was 9.8% for FCSEMS and 15.8% for multiple plastic stents. Pain improvement rate was 85.2% for FCSEMS and 84.2% for multiple plastic stents. CONCLUSIONS: FCSEMS appeared to be no significant difference with multiple plastic stents in treatment of refractory chronic pancreatitis. We need to develop more investigations.


Assuntos
Materiais Biocompatíveis , Metais , Ductos Pancreáticos/cirurgia , Pancreatite/cirurgia , Plásticos , Stents , Doença Crônica , Constrição Patológica/terapia , Humanos , Complicações Pós-Operatórias/epidemiologia , Desenho de Prótese , Reoperação/estatística & dados numéricos , Stents/efeitos adversos
20.
Neurol Ther ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814531

RESUMO

INTRODUCTION: This study aimed to explore influencing factors and clinical significance of ultra-long-term microischemia following intracranial aneurysm (IA) embolization and establish a theoretical foundation for reducing both the incidence of ultra-long-term microischemia and cognitive dysfunction in patients post embolization. METHODS: A retrospective analysis was conducted on data from 147 patients who received endovascular treatment for IAs. Patients were categorized into microischemic and control (non-microischemic) groups on the based on the findings of high-resolution magnetic resonance vessel wall imaging (HR-VWI) examinations performed 3 days postoperatively and 6 months postoperatively. Risk factors for the occurrence of ultra-long-term microischemia were determined by univariate analysis and multivariate logistic regression analysis. RESULTS: Out of 147 patients included in the study, 51 (34.69%) developed microischemia while the remaining 96 (65.31%) did not experience this condition. Analysis revealed that factors such as sex, age, history of underlying diseases (hypertension, diabetes mellitus), aneurysmal site characteristics, the presence or absence of stenosis in the aneurysm-bearing artery, modified Fisher score at admission, Barthel's index at discharge, immunoinflammatory index at 3 days postoperatively and at the 6-month follow-up, the presence or absence of aneurysmal wall enhancement, and the presence or absence of aneurysmal lumen showed no statistically significant differences between the two groups (all P > 0.05). By contrast, variables like in operative time, rupture status of the aneurysm before surgery according to World Federation of Neurologic Surgeons (WFNS) grade, aneurysm size, number of stents used, number of guidewires and catheters used, and Evans index between the two groups were found to have statistically significant disparities between those who developed microischemia and those who did not (P < 0.05). A subsequent multivariate analysis revealed that aneurysm size, Evans index, and the number of stents used were independent risk factors for the occurrence of ultra-long-term microischemia after surgical intervention of aneurysms (P < 0.05). The receiver operating characteristic (ROC) curves of the patients were constructed on the basis of risk factors determined through multivariate logistic regression analysis. Results indicated that aneurysm size (area under ROC curve (AUC) 0.619, sensitivity 94.7%, specificity 17.1%, P = 0.049), Evans index (AUC 0.670, sensitivity 96.4%, specificity 26.8%, P = 0.004), and number of stents (AUC 0.639, sensitivity 44.6%, specificity 90.2%, P < 0.001) effectively predicted the occurrence of microischemia. The incidence of cognitive dysfunction was higher in the microischemic group than in the control group (P < 0.05), and a greater number of microischemic foci was associated with a higher incidence of cognitive dysfunction. The proportion of microschemia foci in the thalamus and basal ganglia in patients with cognitive dysfunction (60.87%) was significantly higher than that in patients without cognitive dysfunction (34.55%) (P < 0.05). CONCLUSION: Aneurysm size, Evans index > 0.3, and the quantity of stents were independent risk factors for the occurrence of ultra-long-term microischemia after aneurysm embolization and provided good predictive performance. Cognitive dysfunction was closely associated with microischemia, with its severity increasing with an increase in the number of ischemic foci.

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