Base de dados : MEDLINE
Pesquisa : D12.776.306.366.100 [Categoria DeCS]
Referências encontradas : 428 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 43 ir para página                         

  1 / 428 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28813434
[Au] Autor:Castro-Garza J; García-Jacobo P; Rivera-Morales LG; Quinn FD; Barber J; Karls R; Haas D; Helms S; Gupta T; Blumberg H; Tapia J; Luna-Cruz I; Rendon A; Vargas-Villarreal J; Vera-Cabrera L; Rodríguez-Padilla C
[Ad] Endereço:Centro de Investigación Biomédica del Noreste, Instituto Mexicano del Seguro Social, Monterrey, Nuevo León, México.
[Ti] Título:Detection of anti-HspX antibodies and HspX protein in patient sera for the identification of recent latent infection by Mycobacterium tuberculosis.
[So] Source:PLoS One;12(8):e0181714, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Mycobacterium tuberculosis is a pathogen causing tuberculosis (TB) a spectrum of disease including acute and asymptomatic latent stages. Identifying and treating latently-infected patients constitutes one of the most important impediments to TB control efforts. Those individuals can remain undiagnosed for decades serving as potential reservoirs for disease reactivation. Tests for the accurate diagnosis of latent infection currently are unavailable. HspX protein (α-crystallin), encoded by Rv2031c gene, is produced in vitro by M. tuberculosis during stationary growth phase and hypoxic or acidic culture conditions. In this study, using standard, and Luminex xMAP® bead capture ELISA, respectively, we report on detection of anti-HspX IgG and IgM antibodies and HspX protein in sera from acute and latent TB patients. For the antibody screen, levels of IgG and IgM antibodies were similar between non-infected and active TB patients; however, individuals classified into the group with latent TB showed higher values of anti-HspX IgM (p = 0.003) compared to active TB patients. Using the bead capture antigen detection assay, HspX protein was detected in sera from 56.5% of putative latent cases (p< 0.050) compared to the background median with an average of 9,900 pg/ml and a range of 1,000 to 36,000 pg/ml. Thus, presence of anti-HspX IgM antibodies and HspX protein in sera may be markers of latent TB.
[Mh] Termos MeSH primário: Antígenos de Bactérias/imunologia
Tuberculose Latente
Mycobacterium tuberculosis/fisiologia
Tuberculose/sangue
Tuberculose/imunologia
alfa-Cristalinas/sangue
alfa-Cristalinas/imunologia
[Mh] Termos MeSH secundário: Antígenos de Bactérias/genética
Proteínas de Bactérias/sangue
Proteínas de Bactérias/genética
Proteínas de Bactérias/imunologia
Reações Cruzadas/imunologia
Ensaio de Imunoadsorção Enzimática
Feminino
Seres Humanos
Imunoglobulina G/sangue
Imunoglobulina G/imunologia
Imunoglobulina M/sangue
Imunoglobulina M/imunologia
Masculino
Tuberculose/microbiologia
alfa-Cristalinas/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antigens, Bacterial); 0 (Bacterial Proteins); 0 (Immunoglobulin G); 0 (Immunoglobulin M); 0 (alpha-Crystallins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171018
[Lr] Data última revisão:
171018
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170817
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0181714


  2 / 428 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28768713
[Au] Autor:Petrou AL; Terzidaki A
[Ad] Endereço:Laboratory of Inorganic Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis, Athens 15771, Greece athpetrou@chem.uoa.gr.
[Ti] Título:A meta-analysis and review examining a possible role for oxidative stress and singlet oxygen in diverse diseases.
[So] Source:Biochem J;474(16):2713-2731, 2017 Aug 02.
[Is] ISSN:1470-8728
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:From kinetic data (k, T) we calculated the thermodynamic parameters for various processes (nucleation, elongation, fibrillization, etc.) of proteinaceous diseases that are related to the ß-amyloid protein (Alzheimer's), to tau protein (Alzheimer's, Pick's), to α-synuclein (Parkinson's), prion, amylin (type II diabetes), and to α-crystallin (cataract). Our calculations led to ΔG values that vary in the range 92.8-127 kJ mol at 310 K. A value of ∼10-30 kJ mol is the activation energy for the diffusion of reactants, depending on the reaction and the medium. The energy needed for the excitation of O from the ground to the first excited state ( Δ , singlet oxygen) is equal to 92 kJ mol So, the ΔG is equal to the energy needed for the excitation of ground state oxygen to the singlet oxygen ( Δ first excited) state. The similarity of the ΔG values is an indication that a common mechanism in the above disorders may be taking place. We attribute this common mechanism to the (same) role of the oxidative stress and specifically of singlet oxygen, ( Δ ), to the above-mentioned processes: excitation of ground state oxygen to the singlet oxygen, Δ , state (92 kJ mol ), and reaction of the empty π* orbital with high electron density regions of biomolecules (∼10-30 kJ mol for their diffusion). The ΔG for cases of heat-induced cell killing (cancer) lie also in the above range at 310 K. The present paper is a review and meta-analysis of literature data referring to neurodegenerative and other disorders.
[Mh] Termos MeSH primário: Peptídeos beta-Amiloides/metabolismo
Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo
alfa-Cristalinas/metabolismo
alfa-Sinucleína/química
Proteínas tau/metabolismo
[Mh] Termos MeSH secundário: Doença de Alzheimer/metabolismo
Doença de Alzheimer/patologia
Peptídeos beta-Amiloides/química
Catarata/metabolismo
Catarata/patologia
Diabetes Mellitus Tipo 2/metabolismo
Diabetes Mellitus Tipo 2/patologia
Metabolismo Energético
Seres Humanos
Polipeptídeo Amiloide das Ilhotas Pancreáticas/química
Estresse Oxidativo
Oxigênio/química
Oxigênio/metabolismo
Doença de Parkinson/metabolismo
Doença de Parkinson/patologia
Oxigênio Singlete
Termodinâmica
alfa-Cristalinas/química
alfa-Sinucleína/metabolismo
Proteínas tau/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; META-ANALYSIS; REVIEW
[Nm] Nome de substância:
0 (Amyloid beta-Peptides); 0 (Islet Amyloid Polypeptide); 0 (alpha-Crystallins); 0 (alpha-Synuclein); 0 (tau Proteins); 17778-80-2 (Singlet Oxygen); S88TT14065 (Oxygen)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170814
[Lr] Data última revisão:
170814
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170804
[St] Status:MEDLINE
[do] DOI:10.1042/BCJ20161058


  3 / 428 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28720375
[Au] Autor:Khoshaman K; Yousefi R; Moosavi-Movahedi AA
[Ad] Endereço:Protein Chemistry Laboratory (PCL), Department of Biology, Shiraz University, Shiraz, Iran.
[Ti] Título:Protective role of antioxidant compounds against peroxynitrite-mediated modification of R54C mutant αA-crystallin.
[So] Source:Arch Biochem Biophys;629:43-53, 2017 Sep 01.
[Is] ISSN:1096-0384
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:As a highly potent reactive oxygen and nitrogen species, peroxynitrite (PON) has endogenous production in the eye ball and contributes to a variety of ocular disorders. In the current study the structural characteristics, chaperone-like activity and conformational stability of R54C mutant αA-crystallin (αA-Cry) were studied upon modification with PON and in the presence of three antioxidant compounds such as ascorbic acid (ASA), glutathione (GSH) and N-acetylcysteine (NAC) using gel electrophoresis and different spectroscopy methods. The results of both fluorescence analysis and gel electrophoresis suggested that PON modification leads to dityrosine-mediated intermolecular cross-linking of this cataractogenic mutant protein. Also, the propensity of R54C mutant αA-Cry for disulfide cross-linking was increased upon PON modification. In addition, the PON-modified protein indicated structural alteration, reduced chemical stability and different pattern of proteolysis. Upon modification with PON, mutant αA-Cry displayed a significant increase in the chaperone-like activity against aggregation of γ-crystallin and insulin. In addition, different antioxidant compounds indicated a prominent role in neutralizing the PON damaging effects on structural integrity and stability of this protein. The results of this study may highlight the importance of antioxidant-rich foods or potent antioxidant supplements in protection of lens crystallins against PON-mediated structural damages and cataract development.
[Mh] Termos MeSH primário: Antioxidantes/farmacologia
Mutação
Ácido Peroxinitroso/farmacologia
alfa-Cristalinas/genética
alfa-Cristalinas/metabolismo
[Mh] Termos MeSH secundário: Seres Humanos
Conformação Proteica/efeitos dos fármacos
Estabilidade Proteica/efeitos dos fármacos
alfa-Cristalinas/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antioxidants); 0 (alpha-Crystallins); 14691-52-2 (Peroxynitrous Acid)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170720
[St] Status:MEDLINE


  4 / 428 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28542382
[Au] Autor:Cetinel S; Semenchenko V; Cho JY; Sharaf MG; Damji KF; Unsworth LD; Montemagno C
[Ad] Endereço:Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada.
[Ti] Título:UV-B induced fibrillization of crystallin protein mixtures.
[So] Source:PLoS One;12(5):e0177991, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Environmental factors, mainly oxidative stress and exposure to sunlight, induce the oxidation, cross-linking, cleavage, and deamination of crystallin proteins, resulting in their aggregation and, ultimately, cataract formation. Various denaturants have been used to initiate the aggregation of crystallin proteins in vitro. All of these regimens, however, are obviously far from replicating conditions that exist in vivo that lead to cataract formation. In fact, it is our supposition that only UV-B radiation may mimic the observed in vivo cause of crystallin alteration leading to cataract formation. This means of inducing cataract formation may provide the most appropriate in vitro platform for in-depth study of the fundamental cataractous fibril properties and allow for testing of possible treatment strategies. Herein, we showed that cataractous fibrils can be formed using UV-B radiation from α:ß:γ crystallin protein mixtures. Characterization of the properties of formed aggregates confirmed the development of amyloid-like fibrils, which are in cross-ß-pattern and possibly in anti-parallel ß-sheet arrangement. Furthermore, we were also able to confirm that the presence of the molecular chaperone, α-crystallin, was able to inhibit fibril formation, as observed for 'naturally' occurring fibrils. Finally, the time-dependent fibrillation profile was found to be similar to the gradual formation of age-related nuclear cataracts. This data provided evidence for the initiation of fibril formation from physiologically relevant crystallin mixtures using UV-B radiation, and that the formed fibrils had several traits similar to that expected from cataracts developing in vivo.
[Mh] Termos MeSH primário: Amiloide/metabolismo
Catarata/metabolismo
Raios Ultravioleta/efeitos adversos
alfa-Cristalinas/metabolismo
gama-Cristalinas/metabolismo
[Mh] Termos MeSH secundário: Seres Humanos
Chaperonas Moleculares/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amyloid); 0 (Molecular Chaperones); 0 (alpha-Crystallins); 0 (gamma-Crystallins)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170911
[Lr] Data última revisão:
170911
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170526
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0177991


  5 / 428 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28182078
[Au] Autor:Zhao J; Shiratori B; Okumura M; Yanai H; Matsumoto M; Nakajima C; Mizuno K; Ono K; Oda T; Chagan-Yasutan H; Ashino Y; Matsuba T; Yoshiyama T; Suzuki Y; Hattori T
[Ad] Endereço:Division of Emerging Infectious Diseases, Department of Internal Medicine, Graduate School of Medicine, Tohoku University, Sendai, Miyagi 980-8574, Japan.
[Ti] Título:Difference in Antibody Responses to Antigens in Japanese Tuberculosis Patients Infected with the Beijing/Non-Beijing Genotype.
[So] Source:J Immunol Res;2017:4797856, 2017.
[Is] ISSN:2314-7156
[Cp] País de publicação:Egypt
[La] Idioma:eng
[Ab] Resumo:The Beijing genotype (MTB), notorious for its virulence and predisposition to relapse, could be identified by spoligotyping based on genetic heterogeneity. The plasma samples from 20 cases of Beijing and 16 cases of non-Beijing MTB infected individuals and 24 healthy controls (HCs) were collected, and antibodies against 11 antigens (Rv0679c142Asn, Rv0679c142Lys, Ag85B, Ag85A, ARC, TDM-M, TDM-K, HBHA, MDP-1, LAM, and TBGL) were measured by ELISA. Compared to the HCs, the MTB infected subjects showed higher titers of anti-Ag85B IgG (positivity 58.2%) and anti-ACR IgG (positivity 48.2%). Of note, anti-ACR IgG showed higher titer in Beijing MTB infected tuberculosis (TB) patients than in HC (Kruskal-Wallis test, < 0.05), while the levels of anti-Ag85B, anti-TBGL, anti-TDM-K, and anti-TDM-M IgG were higher in non-Beijing TB patients than in HC. Moreover, anti-Ag85B IgG showed higher response in non-Beijing TB patients than in Beijing TB patients ( < 0.05; sensitivity, 76.9% versus 44.4%). The sensitivity and specificity analysis showed that 78.8% Beijing infected individuals were negative in anti-TBGL-IgG or/and anti-Ag85B-IgG, while 75.0% of those were positive in anti-TBGL-IgA or/and anti-ACR-IgG tests. These results indicate the possibility of developing antibody-based test to identify Beijing MTB.
[Mh] Termos MeSH primário: Aciltransferases/imunologia
Anticorpos Antibacterianos/imunologia
Antígenos de Bactérias/imunologia
Proteínas de Bactérias/imunologia
Imunoglobulina G/sangue
Mycobacterium tuberculosis/imunologia
Tuberculose Pulmonar/imunologia
alfa-Cristalinas/imunologia
[Mh] Termos MeSH secundário: Feminino
Genótipo
Seres Humanos
Imunoglobulina G/imunologia
Japão
Masculino
Meia-Idade
Mycobacterium tuberculosis/isolamento & purificação
Tuberculose Pulmonar/diagnóstico
Tuberculose Pulmonar/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Antigens, Bacterial); 0 (Bacterial Proteins); 0 (Immunoglobulin G); 0 (alpha-Crystallins); 0 (alpha-crystallin 2, Mycobacterium tuberculosis); 144058-44-6 (Mycobacterium tuberculosis antigens); EC 2.3.- (Acyltransferases); EC 2.3.1.- (antigen 85B, Mycobacterium tuberculosis)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170313
[Lr] Data última revisão:
170313
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170210
[St] Status:MEDLINE
[do] DOI:10.1155/2017/4797856


  6 / 428 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27706231
[Au] Autor:Moafian Z; Khoshaman K; Oryan A; Kurganov BI; Yousefi R
[Ad] Endereço:Protein Chemistry Laboratory (PCL), Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran.
[Ti] Título:Protective Effects of Acetylation on the Pathological Reactions of the Lens Crystallins with Homocysteine Thiolactone.
[So] Source:PLoS One;11(10):e0164139, 2016.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Various post-translational lens crystallins modifications result in structural and functional insults, contributing to the development of lens opacity and cataract disorders. Lens crystallins are potential targets of homocysteinylation, particularly under hyperhomocysteinemia which has been indicated in various eye diseases. Since both homocysteinylation and acetylation primarily occur on protein free amino groups, we applied different spectroscopic methods and gel mobility shift analysis to examine the possible preventive role of acetylation against homocysteinylation. Lens crystallins were extensively acetylated in the presence of acetic anhydride and then subjected to homocysteinylation in the presence of homocysteine thiolactone (HCTL). Extensive acetylation of the lens crystallins results in partial structural alteration and enhancement of their stability, as well as improvement of α-crystallin chaperone-like activity. In addition, acetylation partially prevents HCTL-induced structural alteration and aggregation of lens crystallins. Also, acetylation protects against HCTL-induced loss of α-crystallin chaperone activity. Additionally, subsequent acetylation and homocysteinylation cause significant proteolytic degradation of crystallins. Therefore, further experimentation is required in order to judge effectively the preventative role of acetylation on the structural and functional insults induced by homocysteinylation of lens crystallins.
[Mh] Termos MeSH primário: Homocisteína/análogos & derivados
Cristalino/efeitos dos fármacos
alfa-Cristalinas/química
[Mh] Termos MeSH secundário: Acetilação
Animais
Bovinos
Dicroísmo Circular
Homocisteína/farmacologia
Seres Humanos
Microscopia Eletrônica de Varredura
Conformação Proteica/efeitos dos fármacos
Processamento de Proteína Pós-Traducional
Estabilidade Proteica/efeitos dos fármacos
alfa-Cristalinas/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (alpha-Crystallins); 0LVT1QZ0BA (Homocysteine); D5H88XF24X (homocysteine thiolactone)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170620
[Lr] Data última revisão:
170620
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161006
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0164139


  7 / 428 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27529638
[Au] Autor:Wu Z; Jiang K; Zhu H; Ma C; Yu Z; Li L; Guan W; Liu Y; Zhu H; Chen Y; Li S; Li J; Cheng J; Zhang L; Wang PG
[Ad] Endereço:Department of Chemistry, Georgia State University , Atlanta, Georgia 30303, United States.
[Ti] Título:Site-Directed Glycosylation of Peptide/Protein with Homogeneous O-Linked Eukaryotic N-Glycans.
[So] Source:Bioconjug Chem;27(9):1972-5, 2016 Sep 21.
[Is] ISSN:1520-4812
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Here we report a facile and efficient method for site-directed glycosylation of peptide/protein. The method contains two sequential steps: generation of a GlcNAc-O-peptide/protein, and subsequent ligation of a eukaryotic N-glycan to the GlcNAc moiety. A pharmaceutical peptide, glucagon-like peptide-1 (GLP-1), and a model protein, bovine α-Crystallin, were successfully glycosylated using such an approach. It was shown that the GLP-1 with O-linked N-glycan maintained an unchanged secondary structure after glycosylation, suggesting the potential application of this approach for peptide/protein drug production. In summary, the coupled approach provides a general strategy to produce homogeneous glycopeptide/glycoprotein bearing eukaryotic N-glycans.
[Mh] Termos MeSH primário: Peptídeo 1 Semelhante ao Glucagon/metabolismo
Polissacarídeos/metabolismo
alfa-Cristalinas/metabolismo
[Mh] Termos MeSH secundário: Acetilglucosamina/metabolismo
Sequência de Aminoácidos
Animais
Sítios de Ligação
Bovinos
Células Eucarióticas
Peptídeo 1 Semelhante ao Glucagon/química
Glicosilação
alfa-Cristalinas/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Polysaccharides); 0 (alpha-Crystallins); 89750-14-1 (Glucagon-Like Peptide 1); V956696549 (Acetylglucosamine)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170621
[Lr] Data última revisão:
170621
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160817
[St] Status:MEDLINE
[do] DOI:10.1021/acs.bioconjchem.6b00385


  8 / 428 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
[PMID]:27496206
[Au] Autor:Healy EF; Cervantes L
[Ad] Endereço:Department of Chemistry, St. Edward's University, Austin, TX, 78704, USA. healy@stedwards.edu.
[Ti] Título:An in silico study of the effect of SOD1 electrostatic loop dynamics on amyloid­like filament formation.
[So] Source:Eur Biophys J;45(8):853-859, 2016 Dec.
[Is] ISSN:1432-1017
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Superoxide dismutase [Cu-Zn], or SOD1, is a homo-dimeric protein that functions as an antioxidant by scavenging for superoxides. A wide range of SOD1 variants are linked to inherited, or familial, amyotrophic lateral sclerosis, a progressive and fatal neurodegenerative disease. Aberrant SOD1 oligomerization has been strongly implicated in disease causation, even for sporadic ALS, or SALS, which accounts for ~90 % of ALS cases. Small heat shock proteins (sHSP) have been shown to protect against amyloid fibril formation in vitro, and the sHSP αB-crystallin suppresses in vitro aggregation of SOD1. We are seeking to elucidate the structural features of both SOD1 amyloid formation and αB-crystallin amyloid suppression. Specifically, we have used a flexible docking protocol to refine our model of a SOD1 non-obligate tetramer, postulated to function as a transient desolvating complex. Homology modeling and molecular dynamics (MD) are used to supply the missing structural elements of a previously characterized SOD1 amyloid filament, thereby providing a structural analysis for the observed gain of interaction. This completed filament is then further modified using MD to provide a structural model for protofibril capping of SOD1 filaments by αB-crystallin.
[Mh] Termos MeSH primário: Peptídeos beta-Amiloides/química
Simulação por Computador
Eletricidade Estática
Superóxido Dismutase-1/química
Superóxido Dismutase-1/metabolismo
[Mh] Termos MeSH secundário: Seres Humanos
Ligações de Hidrogênio
Simulação de Dinâmica Molecular
Mutação
Agregados Proteicos
Multimerização Proteica
Estrutura Secundária de Proteína
Superóxido Dismutase-1/genética
alfa-Cristalinas/química
alfa-Cristalinas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amyloid beta-Peptides); 0 (Protein Aggregates); 0 (alpha-Crystallins); EC 1.15.1.1 (Superoxide Dismutase-1)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160807
[St] Status:MEDLINE


  9 / 428 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
PubMed Central Texto completo
Texto completo
[PMID]:27234311
[Au] Autor:Yang J; Zhou S; Guo M; Li Y; Gu J
[Ad] Endereço:State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54S Xianlie, Guangzhou, Guangdong, 510060, People's Republic of China.
[Ti] Título:Different alpha crystallin expression in human age-related and congenital cataract lens epithelium.
[So] Source:BMC Ophthalmol;16:67, 2016 May 28.
[Is] ISSN:1471-2415
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The purpose of this study was to investigate the different expressions of αA-crystallin and αB-crystallin in human lens epithelium of age-related and congenital cataracts. METHODS: The central part of the human anterior lens capsule approximately 5 mm in diameter together with the adhering epithelial cells, were harvested and processed within 6 hours after cataract surgery from age-related and congenital cataract patients or from normal eyes of fresh cadavers. The mRNA and soluble protein levels of αA-crystallin and αB-crystallin in the human lens epithelium were detected by real-time PCR and western blots, respectively. RESULTS: The mRNA and soluble protein expressions of αA-crystallin and αB-crystallin in the lens epithelium were both reduced in age-related and congenital cataract groups when compared with the normal control group. However, the degree of α-crystallin loss in the lens epithelium was highly correlated with different cataract types. The α-crystallin expression of the lens epithelium was greatly reduced in the congenital cataract group but only moderately decreased in the age-related cataract group. The reduction of αA-crystallin soluble protein levels in the congenital cataract group was approximately 2.4 fold decrease compared with that of the age-related cataract group, while an mRNA fold change of 1.67 decrease was observed for the age-related cataract group. Similarly, the reduction of soluble protein levels of αB-crystallin in the congenital cataract group was approximately a 1.57 fold change compared with that of the age-related cataract group. A 1.75 fold change for mRNA levels compared with that of the age-related cataract group was observed. CONCLUSIONS: The results suggest that the differential loss of α-crystallin in the human lens epithelium could be associated with the different mechanisms of cataractogenesis in age-related versus congenital cataracts, subsequently resulting in different clinical presentations.
[Mh] Termos MeSH primário: Catarata/metabolismo
Cristalino/metabolismo
alfa-Cristalinas/metabolismo
beta-Cristalinas/metabolismo
[Mh] Termos MeSH secundário: Idoso
Análise de Variância
Western Blotting
Catarata/congênito
Criança
Pré-Escolar
Epitélio/metabolismo
Feminino
Seres Humanos
Lactente
Masculino
Meia-Idade
RNA Mensageiro/metabolismo
Reação em Cadeia da Polimerase em Tempo Real
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Messenger); 0 (alpha-Crystallins); 0 (beta-Crystallins)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170126
[Lr] Data última revisão:
170126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160529
[St] Status:MEDLINE
[do] DOI:10.1186/s12886-016-0241-1


  10 / 428 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27225040
[Au] Autor:Khan MS; Bhat SA; Tabrez S; Alama MN; Alsenaidy MA; Al-Senaidy AM
[Ad] Endereço:Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia. moskhan@ksu.edu.sa.
[Ti] Título:Denaturation induced aggregation in α-crystallin: differential action of chaotropes.
[So] Source:J Mol Recognit;29(11):536-543, 2016 11.
[Is] ISSN:1099-1352
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:α-Crystallin is a member of small heat shock proteins and is believed to play an exceptional role in the stability of eye lens proteins. The disruption or denaturation of the protein arrangement or solubility of the crystallin proteins can lead to vision problems including cataract. In the present study, we have examined the effect of chemical denaturants urea and guanidine hydrochloride (GdnHCl) on α-crystallin aggregation, with special emphasis on protein conformational changes, unfolding, and amyloid fibril formation. GdnHCl (4 M) induced a 16 nm red shift in the intrinsic fluorescence of α-crystallin, compared with 4 nm shift by 8 M urea suggesting a major change in α-crystallin structure. Circular dichroism analysis showed marked increase in the ellipticity of α-crystallin at 216 nm, suggesting gain in ß-sheet structure in the presence of GdnHCl (0.5-1 M) followed by unfolding at higher concentration (2-6 M). However, only minor changes in the secondary structure of α-crystallin were observed in the presence of urea. Moreover, 8-anilinonaphthalene-1-sulfonic acid fluorescence measurement in the presence of GdnHCl and urea showed changes in the hydrophobicity of α-crystallin. Amyloid studies using thioflavin T fluorescence and congo red absorbance showed that GdnHCl induced amyloid formation in α-crystallin, whereas urea induced aggregation in this protein. Electron microscopy studies further confirmed amyloid formation of α-crystallin in the presence of GdnHCl, whereas only aggregate-like structures were observed in α-crystallin treated with urea. Our results suggest that α-crystallin is susceptible to unfolding in the presence of chaotropic agents like urea and GdnHCl. The destabilized protein has increased likelihood to fibrillate. Copyright © 2016 John Wiley & Sons, Ltd.
[Mh] Termos MeSH primário: Amiloide/metabolismo
Guanidina/farmacologia
Ureia/farmacologia
alfa-Cristalinas/química
[Mh] Termos MeSH secundário: Dicroísmo Circular
Interações Hidrofóbicas e Hidrofílicas
Modelos Moleculares
Desnaturação Proteica/efeitos dos fármacos
Dobramento de Proteína
Estrutura Secundária de Proteína
alfa-Cristalinas/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Amyloid); 0 (alpha-Crystallins); 8W8T17847W (Urea); JU58VJ6Y3B (Guanidine)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171101
[Lr] Data última revisão:
171101
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160527
[St] Status:MEDLINE
[do] DOI:10.1002/jmr.2553



página 1 de 43 ir para página                         
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde