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1.
Front Surg ; 9: 862632, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35965859

RESUMO

Purpose: This study was performed to assess the postoperative recovery outcomes in obese patients undergoing general anesthesia. Methods: The eligible studies were identified from PubMed, EmBase, and the Cochrane library until December 2020. The standard mean differences (SMDs) with 95% confidence intervals (CIs) were used to calculate the role of desflurane, sevoflurane, and propofol on recovery outcomes, and the analyses using the random-effects model. Results: Eleven randomized controlled trials involving 713 obese patients undergoing general anesthesia were selected for final meta-analysis. We noted desflurane was associated with a shorter time to eye-opening than sevoflurane (SMD: -0.86; 95% CI, -1.43 to -0.28; P = 0.003). The use of desflurane with shorter time to extubation as compared with propofol (SMD: -1.13; 95% CI, -1.52 to -0.73; P < 0.001) or sevoflurane (SMD: -1.19; 95% CI, -2.15 to -0.22; P = 0.016), while sevoflurane was associated with longer time to extubation as compared with propofol (SMD: 1.47; 95% CI, 1.03 to 1.91; P < 0.001). Desflurane were associated with shorter time to stating name as compared with propofol (SMD: -1.40; 95% CI, -2.32 to -0.48; P = 0.003) or sevoflurane (SMD: -2.09; 95% CI, -3.33 to -0.85; P = 0.001). In addition, desflurane was associated with a longer time for orientation to place as compared with propofol (SMD: 0.65; 95% CI, 0.22 to 1.07; P = 0.003), while desflurane with shorter time for orientation to place as compared with sevoflurane (SMD: -0.88; 95% CI, -1.46 to -0.30; P = 0.003). Conclusions: The use of desflurane could provide better recovery outcomes in obese patients undergoing general anesthesia. Further large-scale trials should be comparison the long-term effectiveness of various anesthetics.

2.
Sci Rep ; 12(1): 12349, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853971

RESUMO

Despite increased early diagnosis and improved treatment in breast cancer (BRCA) patients, prognosis prediction is still a challenging task due to the disease heterogeneity. This study was to identify a novel gene signature that can accurately evaluate BRCA patient survival. The gene expression and clinical data of BRCA patients were collected from The Cancer Genome Atlas (TCGA) and the Molecular Taxonomy of BRCA International Consortium (METABRIC) databases. Genes associated with prognosis were determined by Kaplan-Meier survival analysis and multivariate Cox regression analysis. A prognostic 16-gene score was established with linear combination of 16 genes. The prognostic value of the signature was validated in the METABRIC and GSE202203 datasets. Gene expression analysis was performed to investigate the diagnostic values of 16 genes. The 16-gene score was associated with shortened overall survival in BRCA patients independently of clinicopathological characteristics. The signalling pathways of cell cycle, oocyte meiosis, RNA degradation, progesterone mediated oocyte maturation and DNA replication were the top five most enriched pathways in the high 16-gene score group. The 16-gene nomogram incorporating the survival-related clinical factors showed improved prediction accuracies for 1-year, 3-year and 5-year survival (area under curve [AUC] = 0.91, 0.79 and 0.77 respectively). MORN3, IGJ, DERL1 exhibited high accuracy in differentiating BRCA tissues from normal breast tissues (AUC > 0.80 for all cases). The 16-gene profile provides novel insights into the identification of BRCA with a high risk of death, which eventually guides treatment decision making.


Assuntos
Neoplasias , Nomogramas , Estimativa de Kaplan-Meier , Prognóstico
3.
J Mol Biol ; 433(11): 166828, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33972023

RESUMO

There is a wide, and continuously widening, gap between the number of proteins known only by their amino acid sequence versus those structurally characterized by direct experiment. To close this gap, we mostly rely on homology-based inference and modeling to reason about the structures of the uncharacterized proteins by using structures of homologous proteins as templates. With the rapidly growing size of the Protein Data Bank, there are often multiple choices of templates, including multiple sets of coordinates from the same protein. The substantial conformational differences observed between different experimental structures of the same protein often reflect function related structural flexibility. Thus, depending on the questions being asked, using distant homologs, or coordinate sets with lower resolution but solved in the appropriate functional form, as templates may be more informative. The ModFlex server (https://modflex.org/) addresses this seldom mentioned gap in the standard homology modeling approach by providing the user with an interface with multiple options and tools to select the most relevant template and explore the range of structural diversity in the available templates. ModFlex is closely integrated with a range of other programs and servers developed in our group for the analysis and visualization of protein structural flexibility and divergence.


Assuntos
Modelos Moleculares , Proteínas/metabolismo , Software , Humanos , Lactoferrina/química , Conformação Proteica , Proteínas/química , Homologia Estrutural de Proteína , Interface Usuário-Computador
4.
EMBO J ; 39(23): e104523, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33073387

RESUMO

Oxidative stress alters cell viability, from microorganism irradiation sensitivity to human aging and neurodegeneration. Deleterious effects of protein carbonylation by reactive oxygen species (ROS) make understanding molecular properties determining ROS susceptibility essential. The radiation-resistant bacterium Deinococcus radiodurans accumulates less carbonylation than sensitive organisms, making it a key model for deciphering properties governing oxidative stress resistance. We integrated shotgun redox proteomics, structural systems biology, and machine learning to resolve properties determining protein damage by γ-irradiation in Escherichia coli and D. radiodurans at multiple scales. Local accessibility, charge, and lysine enrichment accurately predict ROS susceptibility. Lysine, methionine, and cysteine usage also contribute to ROS resistance of the D. radiodurans proteome. Our model predicts proteome maintenance machinery, and proteins protecting against ROS are more resistant in D. radiodurans. Our findings substantiate that protein-intrinsic protection impacts oxidative stress resistance, identifying causal molecular properties.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Estresse Oxidativo/fisiologia , Proteoma/metabolismo , Envelhecimento/metabolismo , Biologia Computacional , Deinococcus/metabolismo , Escherichia coli , Humanos , Aprendizado de Máquina , Doenças Neurodegenerativas/metabolismo , Oxirredução , Conformação Proteica , Processamento de Proteína Pós-Traducional , Proteômica/métodos , Espécies Reativas de Oxigênio/metabolismo , Análise de Sequência de Proteína
5.
Nucleic Acids Res ; 48(W1): W60-W64, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32469061

RESUMO

FATCAT 2.0 server (http://fatcat.godziklab.org/), provides access to a flexible protein structure alignment algorithm developed in our group. In such an alignment, rotations and translations between elements in the structure are allowed to minimize the overall root mean square deviation (RMSD) between the compared structures. This allows to effectively compare protein structures even if they underwent structural rearrangements in different functional forms, different crystallization conditions or as a result of mutations. The major update for the server introduces a new graphical interface, much faster database searches and several new options for visualization of the structural differences between proteins.


Assuntos
Software , Homologia Estrutural de Proteína , Algoritmos , Bases de Dados de Proteínas , Modelos Moleculares , Proteínas/química
6.
Cancer ; 126(14): 3202-3208, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32339256

RESUMO

BACKGROUND: Partner and localizer BRCA2 (PALB2) is a breast cancer predisposition gene, but the clinical relevance of PALB2 germline mutations in Chinese patients with breast cancer remains unknown. This study attempted to investigate the full prevalence and spectrum of PALB2 germline mutations in China and the associations between PALB2 germline mutations and breast cancer risk. METHODS: A total of 21,216 unselected patients with breast cancer were enrolled from 10 provinces in China, and 5890 Chinese women without cancer were enrolled as healthy controls. PALB2 screening was based on next-generation sequencing. RESULTS: A total of 16,501 BRCA1/2-negative patients with breast cancer were analyzed. Deleterious PALB2 mutation carriers accounted for 0.97% (n = 160) in the breast cancer cohort and for 0.19% (n = 11) in the healthy control cohort. Forty-one novel PALB2 germline mutations were identified. A high frequency of PALB2 c.751C>T was detected, and it accounted for 10.63% of the PALB2 germline mutations detected (17 of 160). PALB2 mutations were significantly associated with increased breast cancer risk (odds ratio [OR], 5.23; 95% confidence interval [CI], 2.84-9.65; P < .0001), especially among women 30 years old or younger (OR, 10.09; 95% CI, 3.95-25.79; P < .0001). Clinical characteristics, including a family history, bigger tumor size, triple-negative breast cancer, positive lymph nodes, and bilateral breast cancer, were closely related to PALB2 mutations. CONCLUSIONS: This study revealed a comprehensive spectrum of PALB2 germline mutations and characteristics of PALB2-related breast cancer in China. PALB2 germline mutations confer a moderately increased risk for breast cancer but profoundly increase breast cancer risk for those 30 years old or younger in the Chinese population.


Assuntos
Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Mutação em Linhagem Germinativa , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Programas de Rastreamento/métodos , Neoplasias de Mama Triplo Negativas/genética , Adulto , Proteína BRCA1/genética , Proteína BRCA2/genética , Estudos de Casos e Controles , China/epidemiologia , Estudos de Coortes , Detecção Precoce de Câncer , Feminino , Frequência do Gene , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença , Humanos , Prevalência , Risco , Análise de Sequência de DNA , Neoplasias de Mama Triplo Negativas/epidemiologia , Neoplasias de Mama Triplo Negativas/patologia
7.
PLoS One ; 15(3): e0226702, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32163442

RESUMO

Protein structures, usually visualized in various highly idealized forms focusing on the three-dimensional arrangements of secondary structure elements, can also be described as lists of interacting residues or atoms and visualized as two-dimensional distance or contact maps. We show that contact maps provide an ideal tool to describe and analyze differences between structures of proteins in different conformations. Expanding functionality of the PDBFlex server and database developed previously in our group, we describe how analysis of difference contact maps (DCMs) can be used to identify critical interactions stabilizing alternative protein conformations, recognize residues and positions controlling protein functions and build hypotheses as to molecular mechanisms of disease mutations.


Assuntos
Biologia Computacional/métodos , Modelos Moleculares , Estrutura Secundária de Proteína , Proteínas/química , Algoritmos , Sítios de Ligação , Ligantes , Ligação Proteica , Proteínas/metabolismo
8.
Nucleic Acids Res ; 47(D1): D895-D899, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30407596

RESUMO

Our knowledge of cancer genomics exploded in last several years, providing us with detailed knowledge of genetic alterations in almost all cancer types. Analysis of this data gave us new insights into molecular aspects of cancer, most important being the amazing diversity of molecular abnormalities in individual cancers. The most important question in cancer research today is how to classify this diversity to identify subtypes that are most relevant for treatment and outcome prediction for individual patients. The Cancer3D database at http://www.cancer3d.org gives an open and user-friendly way to analyze cancer missense mutations in the context of structures of proteins they are found in and in relation to patients' clinical data. This approach allows users to find novel candidate driver regions for specific subgroups, that often cannot be found when similar analyses are done on the whole gene level and for large, diverse cohorts. Interactive interface allows user to visualize the distribution of mutations in subgroups defined by cancer type and stage, gender and age brackets, patient's ethnicity or vice versa find dominant cancer type, gender or age groups for specific three-dimensional mutation patterns.


Assuntos
Bases de Dados de Proteínas , Mutação de Sentido Incorreto , Neoplasias/genética , Conformação Proteica , Proteínas/genética , Humanos , Domínios Proteicos
9.
Cell Physiol Biochem ; 49(6): 2099-2110, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30257238

RESUMO

BACKGROUND: Propofol is a commonly used anaesthetic with controversial effects on cancer cells. We aimed to explore the functional roles of propofol in hepatocellular carcinoma (HCC) cells as well as the underlying mechanisms. METHODS: HepG2 and SMMC-7721 cells were used in this study. Firstly, the effects of propofol on cell viability, migration, invasion, apoptosis, and involved proteins were assessed by Cell Counting Kit-8 assay, Transwell assay, flow cytometry assay and Western blot analysis, respectively. Subsequently, alteration of miR-374a after stimulation of propofol was analyzed by qRT-PCR. miR-374a was overexpressed and the alteration of proteins in the Wnt/ß-catenin and PI3K/AKT pathways was detected by Western blot analysis. The downstream factor of miR-374a was finally studied. RESULTS: Propofol inhibited cell viability, migration and invasion but promoted apoptosis of HepG2 and SMMC-7721 cells. Meanwhile, cyclinD1, matrix metalloproteinase (MMP)-2 and MMP-9 were down-regulated while Bax/Bcl-2, cleaved caspase-3 and cleaved caspase-9 were up-regulated by propofol. Then, miR-374a level was reduced by propofol. Expression of Wnt3a, ß-catenin, p-PI3K and p-AKT was decreased by propofol, whereas these decreases were reversed by miR-374a overexpression. Finally, TP53 was proven to be target of miR-374a in HepG2 cells. CONCLUSION: Propofol inhibited cell proliferation, migration and invasion while promoted cell apoptosis of HepG2 and SMMC-7721 cells through inhibiting the Wnt/ß-catenin and PI3K/ AKT pathways via down-regulation of miR-374a. Besides, miR-374a affected propofol-treated HepG2 cells by targeting TP53.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , MicroRNAs/metabolismo , Propofol/farmacologia , Regiões 3' não Traduzidas , Antagomirs/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Caspase 3/metabolismo , Movimento Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos
10.
Medicine (Baltimore) ; 97(10): e9700, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29517692

RESUMO

The aim of this study was to systematically evaluate the effect of blood transfusion (BT) on postoperative atrial fibrillation (AF) in adult patients who had undergone coronary artery bypass grafting (CABG) surgery.PubMed, Embase, and Cochrane Library databases from inception to January 2017 were searched. Cohort studies were searched that evaluated the association between BT and the risk of postoperative AF in adult patients who had undergone CABG surgery. Study quality was assessed by using the Newcastle-Ottawa scale (NOS). A meta-analysis was performed with the random-effect model.Eight cohort studies involving 7401 AF cases and 31,069 participants were identified and included in our data analysis. The pooled odds ratio of postoperative AF in patients with BT was 1.45 (95% confidence interval, 1.26-1.67), with significant heterogeneity (P < .0001, I = 79%). Excluding one study that had an off-pump CABG did not significantly impact this result (odds ratio, 1.36; 95% confidence interval, 1.23-1.50; n = 7). To examine the stability of the primary results, we performed subgroup analyses. The association between BT and the risk of postoperative AF was similar, as determined in the stratified analyses conducted according to study design, type of surgery, and country.The findings of the present meta-analysis demonstrated a statistically significant increase in postoperative AF risk among adult patients with BT. Further prospective large-scale studies are needed to establish causality and to elucidate the underlying mechanisms.


Assuntos
Fibrilação Atrial/etiologia , Transfusão de Sangue/métodos , Ponte de Artéria Coronária/efeitos adversos , Complicações Pós-Operatórias , Reação Transfusional/complicações , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Período Pós-Operatório
11.
J Ultrasound Med ; 36(4): 749-756, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28150413

RESUMO

OBJECTIVES: Previous studies have demonstrated a high frequency of gas emboli during hysteroscopy, but guidelines for the prevention, early detection, and intervention of gas embolism during hysteroscopic procedures are still lacking. This study aimed to gain a clearer understanding of risk factors and specific signs and symptoms associated with gas emboli. METHODS: This prospective study enrolled 120 women scheduled for hysteroscopy using 5% glucose as distension medium. The gas bubbles were monitored sequentially in internal iliac vein, common iliac vein, inferior vena cava, superior vena cava, heart, and pulmonary artery under the gray-scale imaging of Doppler ultrasound. The frequency, extent, and the hemodynamic and respiratory effects of gas emboli were evaluated. The interventions and outcomes were recorded. The risk factors associated with gas emboli, and their relationship with the frequency and extent of gas emboli, were assessed. RESULTS: In our study, evidence of gas emboli under Doppler ultrasound monitoring was observed in 44 (36.7%) patients. The operation was continued and finished as soon as possible for patients presenting with stable vital signs or transient hemodynamic and respiratory changes, which resolved spontaneously without intervention. The operation was paused for patients presenting with significant hemodynamic changes or loss of consciousness, and the operation was resumed shortly after resumption of stable vital signs following symptomatic treatment. All patients in our study finished the operation and recovered without developing serious complications. Data analysis showed prolonged procedure duration and increased bleeding volume were both positively correlated with the frequency and extent of gas emboli. CONCLUSION: Our study demonstrated a high frequency of gas emboli during hysteroscopy. Doppler ultrasonic monitoring combined with a clearer understanding of specific signs, symptoms, and risk factors will facilitate early detection and intervention of gas emboli during hysteroscopy.


Assuntos
Embolia Aérea/diagnóstico por imagem , Histeroscopia/métodos , Ultrassonografia Doppler/métodos , Adulto , Idoso , Feminino , Coração/diagnóstico por imagem , Humanos , Veia Ilíaca/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Veias Cavas/diagnóstico por imagem , Adulto Jovem
12.
Clin Lab ; 63(1): 53-58, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28164487

RESUMO

BACKGROUND: The aim of this study was to evaluate the predictive value of serum human epidermal growth factor 2 (HER2) for recurrence and metastasis in triple negative breast cancer (TNBC). METHODS: A total of 200 patients with benign breast tumors and 300 patients with breast cancer treated in the Department of Breast Surgery, Women and Children's Hospital of Ningbo City (China) between December 2006 and December 2013 were enrolled. Another 500 age- and gender-matched healthy individuals served as controls. The serum level of HER2 was determined using suspension array technology. Patients with breast cancer were further divided into ER-/PR-/HER2- and ER-/PR-/HER2+ groups and followed up for 5 years to analyze the serum concentration of HER2. RESULTS: The serum HER2 concentration was significantly higher in patients with breast cancer than in healthy controls or patients with benign tumors (both p < 0.01). The serum HER2 concentration also was significantly higher in patients with TNBC than in healthy controls (p < 0.01). The serum concentration of HER2 was significantly higher in TNBC patients who experienced recurrence and metastasis than in TNBC patients who did not experience recurrence and metastasis (both p < 0.01). Notably, the serum HER2 concentration in TNBC patients who experienced recurrence and metastasis was increased to a level statistically similar to that in patients with HER2+ breast cancer (p > 0.05). CONCLUSIONS: Patients with TNBC still have an increased serum HER2 concentration, and serum HER2 may be a valuable, novel biomarker for recurrence and metastasis in TNBC.


Assuntos
Biomarcadores Tumorais/sangue , Recidiva Local de Neoplasia , Receptor ErbB-2/sangue , Neoplasias de Mama Triplo Negativas/sangue , China , Feminino , Humanos , Metástase Neoplásica , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia , Regulação para Cima
13.
Nucleic Acids Res ; 44(D1): D423-8, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26615193

RESUMO

The PDBFlex database, available freely and with no login requirements at http://pdbflex.org, provides information on flexibility of protein structures as revealed by the analysis of variations between depositions of different structural models of the same protein in the Protein Data Bank (PDB). PDBFlex collects information on all instances of such depositions, identifying them by a 95% sequence identity threshold, performs analysis of their structural differences and clusters them according to their structural similarities for easy analysis. The PDBFlex contains tools and viewers enabling in-depth examination of structural variability including: 2D-scaling visualization of RMSD distances between structures of the same protein, graphs of average local RMSD in the aligned structures of protein chains, graphical presentation of differences in secondary structure and observed structural disorder (unresolved residues), difference distance maps between all sets of coordinates and 3D views of individual structures and simulated transitions between different conformations, the latter displayed using JSMol visualization software.


Assuntos
Bases de Dados de Proteínas , Conformação Proteica , Ligantes , Modelos Moleculares
14.
Bioinformatics ; 31(13): 2098-105, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25701568

RESUMO

MOTIVATION: Most proteins consist of multiple domains, independent structural and evolutionary units that are often reshuffled in genomic rearrangements to form new protein architectures. Template-based modeling methods can often detect homologous templates for individual domains, but templates that could be used to model the entire query protein are often not available. RESULTS: We have developed a fast docking algorithm ab initio domain assembly (AIDA) for assembling multi-domain protein structures, guided by the ab initio folding potential. This approach can be extended to discontinuous domains (i.e. domains with 'inserted' domains). When tested on experimentally solved structures of multi-domain proteins, the relative domain positions were accurately found among top 5000 models in 86% of cases. AIDA server can use domain assignments provided by the user or predict them from the provided sequence. The latter approach is particularly useful for automated protein structure prediction servers. The blind test consisting of 95 CASP10 targets shows that domain boundaries could be successfully determined for 97% of targets. AVAILABILITY AND IMPLEMENTATION: The AIDA package as well as the benchmark sets used here are available for download at http://ffas.burnham.org/AIDA/. CONTACT: adam@sanfordburnham.org SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Biologia Computacional/métodos , Modelos Teóricos , Conformação Proteica , Proteínas/química , Proteínas/metabolismo , Software , Algoritmos , Humanos , Internet , Domínios e Motivos de Interação entre Proteínas , Estrutura Terciária de Proteína , Análise de Sequência de Proteína
15.
Cell Physiol Biochem ; 33(6): 1863-75, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24969755

RESUMO

BACKGROUND/AIMS: The ubiquitin-specific peptidase USP22 mediates various cellular and organismal processes, such as cell growth, apoptosis, and tumor malignancy. However, the molecular mechanisms that regulate USP22 activity remain poorly understood. Here we identify STAT3 as a new USP22 interactor. METHODS: · We used western blotting and RT-PCR to measure key protein, acetylated STAT3, and mRNA levels in HEK293 and colorectal cancer cell lines transfected with expression plasmids or specific siRNAs. Co-immunoprecipitation was used to demonstrate protein-protein interaction and protein complex composition. RESULTS: USP22 overexpression down-regulated STAT3 acetylation by deubiquitinating SIRT1. The three proteins were found to be present in a single protein complex. SiRNA-mediated depletion of endogenous USP22 resulted in SIRT1 destabilization and elevated STAT3 acetylation. Consistent with this finding, USP22 also down-regulated the expression of two known STAT3 target genes, MMP9 and TWIST. CONCLUSION: We show that USP22 is a new regulator of the SIRT1-STAT3 signaling pathway and report a new mechanistic explanation for cross talk between USP22 and the SIRT1-STAT pathways.


Assuntos
Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo , Tioléster Hidrolases/metabolismo , Acetilação , Western Blotting , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Microscopia de Fluorescência , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética , Tioléster Hidrolases/genética , Ubiquitina Tiolesterase , Ubiquitinação
16.
Nucleic Acids Res ; 42(Web Server issue): W240-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24838569

RESUMO

POSA (Partial Order Structure Alignment), available at http://posa.godziklab.org, is a server for multiple protein structure alignment introduced in 2005 (Ye,Y. and Godzik,A. (2005) Multiple flexible structure alignment using partial order graphs. Bioinformatics, 21, 2362-2369). It is free and open to all users, and there is no login requirement, albeit there is an option to register and store results in individual, password-protected directories. In the updated POSA server described here, we introduce two significant improvements. First is an interface allowing the user to provide additional information by defining segments that anchor the alignment in one or more input structures. This interface allows users to take advantage of their intuition and biological insights to improve the alignment and guide it toward a biologically relevant solution. The second improvement is an interactive visualization with options that allow the user to view all superposed structures in one window (a typical solution for visualizing results of multiple structure alignments) or view them individually in a series of synchronized windows with extensive, user-controlled visualization options. The user can rotate structure(s) in any of the windows and study similarities or differences between structures clearly visible in individual windows.


Assuntos
Software , Homologia Estrutural de Proteína , Algoritmos , Internet , Interface Usuário-Computador
17.
Nucleic Acids Res ; 42(Web Server issue): W308-13, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24831546

RESUMO

AIDA: ab initio domain assembly server, available at http://ffas.burnham.org/AIDA/ is a tool that can identify domains in multi-domain proteins and then predict their 3D structures and relative spatial arrangements. The server is free and open to all users, and there is an option for a user to provide an e-mail to get the link to result page. Domains are evolutionary conserved and often functionally independent units in proteins. Most proteins, especially eukaryotic ones, consist of multiple domains while at the same time, most experimentally determined protein structures contain only one or two domains. As a result, often structures of individual domains in multi-domain proteins can be accurately predicted, but the mutual arrangement of different domains remains unknown. To address this issue we have developed AIDA program, which combines steps of identifying individual domains, predicting (separately) their structures and assembling them into multiple domain complexes using an ab initio folding potential to describe domain-domain interactions. AIDA server not only supports the assembly of a large number of continuous domains, but also allows the assembly of domains inserted into other domains. Users can also provide distance restraints to guide the AIDA energy minimization.


Assuntos
Estrutura Terciária de Proteína , Software , Internet , Análise de Sequência de Proteína
18.
BMC Bioinformatics ; 15: 112, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24742328

RESUMO

BACKGROUND: Bacteroides spp. form a significant part of our gut microbiome and are well known for optimized metabolism of diverse polysaccharides. Initial analysis of the archetypal Bacteroides thetaiotaomicron genome identified 172 glycosyl hydrolases and a large number of uncharacterized proteins associated with polysaccharide metabolism. RESULTS: BT_1012 from Bacteroides thetaiotaomicron VPI-5482 is a protein of unknown function and a member of a large protein family consisting entirely of uncharacterized proteins. Initial sequence analysis predicted that this protein has two domains, one on the N- and one on the C-terminal. A PSI-BLAST search found over 150 full length and over 90 half size homologs consisting only of the N-terminal domain. The experimentally determined three-dimensional structure of the BT_1012 protein confirms its two-domain architecture and structural analysis of both domains suggests their specific functions. The N-terminal domain is a putative catalytic domain with significant similarity to known glycoside hydrolases, the C-terminal domain has a beta-sandwich fold typically found in C-terminal domains of other glycosyl hydrolases, however these domains are typically involved in substrate binding. We describe the structure of the BT_1012 protein and discuss its sequence-structure relationship and their possible functional implications. CONCLUSIONS: Structural and sequence analyses of the BT_1012 protein identifies it as a glycosyl hydrolase, expanding an already impressive catalog of enzymes involved in polysaccharide metabolism in Bacteroides spp. Based on this we have renamed the Pfam families representing the two domains found in the BT_1012 protein, PF13204 and PF12904, as putative glycoside hydrolase and glycoside hydrolase-associated C-terminal domain respectively.


Assuntos
Proteínas de Bactérias/química , Glicosídeo Hidrolases/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Bacteroides/enzimologia , Biologia Computacional , Trato Gastrointestinal/microbiologia , Genômica , Glicosídeo Hidrolases/genética , Humanos , Estrutura Terciária de Proteína
19.
Nucleic Acids Res ; 42(Database issue): D1133-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24214957

RESUMO

The discovery of broadly neutralizing antibodies (bNAbs) has provided an enormous impetus to the HIV vaccine research and to entire immunology. The bNAber database at http://bNAber.org provides open, user-friendly access to detailed data on the rapidly growing list of HIV bNAbs, including neutralization profiles, sequences and three-dimensional structures (when available). It also provides an extensive list of visualization and analysis tools, such as heatmaps to analyse neutralization data as well as structure and sequence viewers to correlate bNAbs properties with structural and sequence features of individual antibodies. The goal of the bNAber database is to enable researchers in this field to easily compare and analyse available information on bNAbs thereby supporting efforts to design an effective vaccine for HIV/AIDS. The bNAber database not only provides easy access to data that currently is scattered in the Supplementary Materials sections of individual papers, but also contributes to the development of general standards of data that have to be presented with the discovery of new bNAbs and a universal mechanism of how such data can be shared.


Assuntos
Anticorpos Neutralizantes/química , Bases de Dados de Proteínas , Anticorpos Anti-HIV/química , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Complexo Antígeno-Anticorpo/química , Anticorpos Anti-HIV/imunologia , Anticorpos Anti-HIV/farmacologia , Concentração Inibidora 50 , Internet , Conformação Proteica , Software
20.
Bioinformatics ; 30(5): 660-7, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24130308

RESUMO

MOTIVATION: Homology detection enables grouping proteins into families and prediction of their structure and function. The range of application of homology-based predictions can be significantly extended by using sequence profiles and incorporation of local structural features. However, incorporation of the latter terms varies a lot between existing methods, and together with many examples of distant relations not recognized even by the best methods, suggests that further improvements are still possible. RESULTS: Here we describe recent improvements to the fold and function assignment system (FFAS) method, including adding optimized structural features (experimental or predicted), 'symmetrical' Z-score calculation and re-ranking the templates with a neural network. The alignment accuracy in the new FFAS-3D is now 11% higher than the original and comparable with the most accurate template-based structure prediction algorithms. At the same time, FFAS-3D has high success rate at the Structural Classification of Proteins (SCOP) family, superfamily and fold levels. Importantly, FFAS-3D results are not highly correlated with other programs suggesting that it may significantly improve meta-predictions. FFAS-3D does not require 3D structures of the templates, as using predicted features instead of structure-derived does not lead to the decrease of accuracy. Because of that, FFAS-3D can be used for databases other than Protein Data Bank (PDB) such as Protein families database or Clusters of orthologous groups thus extending its applications to functional annotations of genomes and protein families. AVAILABILITY AND IMPLEMENTATION: FFAS-3D is available at http://ffas.godziklab.org.


Assuntos
Conformação Proteica , Homologia de Sequência de Aminoácidos , Algoritmos , Bases de Dados de Proteínas , Redes Neurais de Computação , Dobramento de Proteína , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas/química , Proteínas/classificação , Alinhamento de Sequência
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