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1.
Int. arch. otorhinolaryngol. (Impr.) ; 19(1): 80-85, Jan-Mar/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-741526

RESUMO

Introduction Obstructive sleep apnea syndrome affects up to 4% of middle-aged men and 2% of adult women. It is associated with obesity. Objective The objective of this article is to review the literature to determine which factors best correlate with treatment success in patients with obstructive sleep apnea syndrome treated with a mandibular repositioning appliance. Data Synthesis A search was performed of the PubMed, Cochrane, Lilacs, Scielo, and Web of Science databases of articles published from January 1988 to January 2012. Two review authors independently collected data and assessed trial quality. Sixty-nine articles were selected from PubMed and 1 from Cochrane library. Of these, 42 were excluded based on the title and abstract, and 27 were retrieved for complete reading. A total of 13 articles and 1 systematic review were considered eligible for further review and inclusion in this study: 6 studies evaluated anthropomorphic and physiologic factors, 3 articles addressed cephalometric and anatomic factors, and 4 studies evaluated variables related to mandibular repositioning appliance design and activation. All the studies evaluated had low to moderate methodologic quality and were not able to support evidence on prediction of treatment success. Conclusion Based on this systematic review on obstructive sleep apnea syndrome treatment, it remains unclear which predictive factors can be used with confidence to select patients suitable for treatment with a mandibular repositioning appliance. .


Assuntos
Animais , Evolução Biológica , Proteínas de Transporte/química , Cinesinas/química , Modelos Moleculares , Microtúbulos/metabolismo , Transporte Biológico/fisiologia , Chlorocebus aethiops , Células COS , Dimerização , Transferência Ressonante de Energia de Fluorescência , Cinética , Microscopia de Fluorescência
2.
Experimental & Molecular Medicine ; : e158-2015.
Artigo em Coreano | WPRIM | ID: wpr-147140

RESUMO

Gephyrin is a central element that anchors, clusters and stabilizes glycine and gamma-aminobutyric acid type A receptors at inhibitory synapses of the mammalian brain. It self-assembles into a hexagonal lattice and interacts with various inhibitory synaptic proteins. Intriguingly, the clustering of gephyrin, which is regulated by multiple posttranslational modifications, is critical for inhibitory synapse formation and function. In this review, we summarize the basic properties of gephyrin and describe recent findings regarding its roles in inhibitory synapse formation, function and plasticity. We will also discuss the implications for the pathophysiology of brain disorders and raise the remaining open questions in this field.


Assuntos
Animais , Humanos , Proteínas de Transporte/química , Suscetibilidade a Doenças , Neurônios GABAérgicos/metabolismo , Regulação da Expressão Gênica , Proteínas de Membrana/química , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Processamento de Proteína Pós-Traducional , Transporte Proteico , Sinapses/metabolismo
3.
Indian J Exp Biol ; 2013 Dec; 51(12): 1055-1062
Artigo em Inglês | IMSEAR | ID: sea-150292

RESUMO

yielded an average particle size of 120 nm with 70% encapsulation-efficiency. In vitro release profile of NP-OP showed sustained release of OP for 21 days. In vivo anti-fertility studies were conducted in marmosets. Results indicated that control animals conceived in the same cycle while two of three treated animals failed to conceive in treatment cycle. The in vivo studies thus corroborate with in vitro release of OP, demonstrating its anti-fertility activity in 66% of animals.


Assuntos
Animais , Callithrix/fisiologia , Proteínas de Transporte/administração & dosagem , Proteínas de Transporte/química , Anticoncepção , Feminino , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/química , Folículo Ovariano/química , Tamanho da Partícula , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/química , Polímeros/administração & dosagem , Polímeros/química
4.
Indian J Biochem Biophys ; 2007 Feb; 44(1): 44-9
Artigo em Inglês | IMSEAR | ID: sea-27422

RESUMO

Kaliocin-1, a 31-residue synthetic peptide (FFSASCVPGADKGQFPNLCRLCA GTGENKCA), which has shown the antimicrobial activity forms the 152-182 fragment of human lactoferrin (HLf). As the octapeptide FSASCVPG forms the 2-9 fragment of kaliocin-1, in the present study, its conformation in dimethyl sulfoxide-d6 (DMSO-d6) has been determined using two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy as well as restrained molecular dynamics. Sequence specific assignments of all the 1H resonances have been carried out using 2D correlation experiments (2D DQF-COSY, TOCSY and ROESY). In dimethyl sulfoxide-d6 at 25 degrees C, the octapeptide adopts a predominantly extended backbone conformation. The calculated structure resembles closely with the reported structure of the corresponding fragment of HLf. The peptide also has sequence and structural similarity with the corresponding fragments of lactoferrins from other organisms.


Assuntos
Sequência de Aminoácidos , Proteínas de Transporte/química , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Fragmentos de Peptídeos/química , Estrutura Secundária de Proteína , Termodinâmica
5.
Genet. mol. res. (Online) ; 6(4): 1169-1177, 2007. ilus, graf
Artigo em Inglês | LILACS | ID: lil-520032

RESUMO

The oligopeptide-binding protein, OppA, ushers oligopeptide substrates to the membrane-associated oligopeptide permease (Opp), a multi-component ABC-type transporter involved in the uptake of oligopeptides by several bacterial species. In the present study, we report a structural model and an oligopeptide docking analysis of the OppA protein expressed by Xanthomonas axonopodis pv. citri (X. citri), the etiological agent of citrus canker. The X. citri OppA structural model showed a conserved three-dimensional structure, irrespective of the low amino acid identities with previously defined structures of Bacillus subtilis and Salmonella typhimurium orthologs. Oligopeptide docking analysis carried out with the proposed model indicated that the X. citri OppA preferentially binds tri- and tetrapeptides. The present study represents the first structural analysis of an OppA ortholog expressed by a phytopathogen and contributes to the understanding of the physiology and nutritional strategies of X. citri.


Assuntos
Lipoproteínas/química , Oligopeptídeos/metabolismo , Proteínas de Bactérias/química , Proteínas de Transporte/química , Xanthomonas/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Doenças das Plantas/microbiologia , Ligantes , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica
7.
Indian J Biochem Biophys ; 2006 Oct; 43(5): 319-22
Artigo em Inglês | IMSEAR | ID: sea-27502

RESUMO

The low molecular mass proteins found in the pheromonal sources such as urine, saliva, glandular secretion etc have been reported as ligand carriers for the processes of chemocommunication in mammals. The preputial gland plays an important role in the production of olfactory signals for pheromonal communication. Thus, in the present study, alpha-2u globulin having molecular mass of 18 kDa has been identified in the preputial gland of Norway rat (Rattus norvegicus) by in-gel trypsin digestion and analyzing the resulting peptides by MALDI-TOF. Since preputial gland is one of the major pheromonal sources in rat, the results suggest that alpha-2u globulin might act as a carrier for hydrophobic odorants of preputial gland.


Assuntos
alfa-Globulinas/química , Sequência de Aminoácidos , Animais , Proteínas de Transporte/química , Genitália Masculina/metabolismo , Lipocalina 1 , Masculino , Dados de Sequência Molecular , Peptídeos/química , Feromônios/química , Ligação Proteica , Ratos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Tripsina/química
8.
Indian J Biochem Biophys ; 2006 Oct; 43(5): 323-6
Artigo em Inglês | IMSEAR | ID: sea-26815

RESUMO

The extraction and carrier-facilitated transport of amino acids (leucine, valine and glycine) was studied through chloroform bulk liquid membrane system using a series of non-cyclic receptors such as diethylene glycol (1), diethylene glycol dimethyl ether (2), diethylene glycol dibutyl ether (3), diethylene glycol dibenzoate (4), triethylene glycol (5) and tetraethylene glycol (6). The amount of amino acid extracted and transported depends mainly upon the structure and the concentration of the receptors and also on the concentration of amino acid. The receptors 1 to 4, having small chain length and flexible end groups, formed stable complexes with amino acids, and the flexibility of receptors in different conformational forms was responsible for their carrier ability, while the receptors 5 and 6, having larger chain length showed poor carrier ability. Hydrophobicity of amino acids also play an important role in the extraction as well as transport process.


Assuntos
Aminoácidos/química , Transporte Biológico , Transporte Biológico Ativo , Proteínas de Transporte/química , Portador Sadio , Membrana Celular/metabolismo , Glicina/química , Leucina/química , Modelos Biológicos , Modelos Químicos , Fatores de Tempo , Valina/química
9.
Experimental & Molecular Medicine ; : 434-443, 2002.
Artigo em Inglês | WPRIM | ID: wpr-13045

RESUMO

The release of neurotransmitter is regulated in the processes of membrane docking and membrane fusion between synaptic vesicles and presynaptic plasma membranes. Synaptic vesicles contain a diverse set of proteins that participate in these processes. Small GTP-binding proteins exist in the synaptic vesicles and are suggested to play roles for the regulation of neurotransmitter release. We have examined a possible role of GTP-binding proteins in the regulation of protein phosphorylation in the synaptic vesicles. GTPgammaS stimulated the phosphorylation of 46 kappa Da protein (p46) with pI value of 5.0-5.2, but GDPbetaS did not. The p46 was identified as protein interacting with C-kinase 1 (PICK-1) by MALDI-TOF mass spectroscopy analysis, and anti-PICK-1 antibody recognized the p46 spot on 2-dimensional gel electrophoresis. Rab guanine nucleotide dissociation inhibitor (RabGDI), which dissociates Rab proteins from SVs, did not affect phosphorylation of p46. Ca2+/ calmodulin (CaM), which causes the small GTP- binding proteins like Rab3A and RalA to dissociate from the membranes and stimulates CaM- dependnet protein kinase(s) and phosphatase, strongly stimulate the phosphorylation of p46 in the presence of cyclosporin A and cyclophylin. However, RhoGDI, which dissociates Rho proteins from membranes, reduced the phosphorylation of p46 to the extent of about 50%. These results support that p46 was PICK-1, and its phosphorylation was stimulated by GTP and Ca2+/CaM directly or indirectly through GTP-binding protein(s) and Ca2+/CaM effector protein(s). The phosphorylation of p46 (PICK-1) by GTP and Ca2+/CaM may be important for the regulation of transporters and neurosecretion.


Assuntos
Animais , Ratos , Cálcio/metabolismo , Calmodulina/metabolismo , Proteínas de Transporte/química , Inibidores de Dissociação do Nucleotídeo Guanina/metabolismo , Guanosina Trifosfato/metabolismo , Peso Molecular , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Recombinantes de Fusão/química , Membranas Sinápticas/química , Vesículas Sinápticas/química
10.
Indian J Exp Biol ; 2001 Aug; 39(8): 781-5
Artigo em Inglês | IMSEAR | ID: sea-55691

RESUMO

Indian toad (Bufo melanostictus, Schneider) skin extract (TSE) is pharmacologically potent and probably contains several bioactive compounds [Das et. al., Indian J Pharmacol, 28 (1996) 72]. A lethal factor was isolated and purified by neutral alumina column chromatography followed by HPLC. Spectroscopic (UV, IR, FAB-MASS) study indicated that the lethal factor (TSE-LF) was a 254 Da long chain compound with carbonyl, hydroxyl and ester as functional groups. LD50 of TSE-LF was found to be 3.5 mg/kg (iv). Biological study showed that TSE-LF possesses hypotensive, cardiotoxic, neurotoxic activity and produced death by apnoea in experimental animal. Cyproheptadine antagonised TSE-LF induced contraction of isolated smooth muscle indicating involvement of histamine/serotonin receptors. TSE-LF induced neurotoxic action on chick biventer cervices was mediated through Ca2+ ion.


Assuntos
Animais , Antígenos de Bactérias , Toxinas Bacterianas , Bufonidae , Sistema Cardiovascular/efeitos dos fármacos , Proteínas de Transporte/química , Cromatografia Líquida de Alta Pressão , Cobaias , Dose Letal Mediana , Ratos , Pele/química , Análise Espectral
11.
Braz. j. med. biol. res ; 34(1): 27-34, Jan. 2001. ilus
Artigo em Inglês | LILACS | ID: lil-277053

RESUMO

The presence of chitin in midgut structures of Callosobruchus maculatus larvae was shown by chemical and immunocytochemical methods. Detection by Western blotting of cowpea (Vigna unguiculata) seed vicilins (7S storage proteins) bound to these structures suggested that C. maculatus-susceptible vicilins presented less staining when compared to C. maculatus-resistant vicilins. Storage proteins present in the microvilli in the larval midgut of the bruchid were recognized by immunolabeling of vicilins in the appropriate sections with immunogold conjugates. These labeling sites coincided with the sites labeled by an anti-chitin antibody. These results, taken together with those previously published showing that the lower rates of hydrolysis of variant vicilins from C. maculatus-resistant seeds by the insect's midgut proteinases and those showing that vicilins bind to chitin matrices, may explain the detrimental effects of variant vicilins on the development of C. maculatus larvae


Assuntos
Animais , Besouros/metabolismo , Quitina/análise , Fabaceae/metabolismo , Intestinos/química , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Western Blotting , Proteínas de Transporte/química , Proteínas de Transporte/isolamento & purificação , Proteínas de Transporte/metabolismo , Quitina/metabolismo , Fabaceae/química , Intestinos/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Sementes/química
12.
Experimental & Molecular Medicine ; : 89-94, 2001.
Artigo em Inglês | WPRIM | ID: wpr-42076

RESUMO

Clathrin-mediated vesicle formation is an essential step in the intracellular trafficking of the protein and lipid. Binding of clathrin assembly protein to clathrin triskelia induces their assembly into clathrin-coated vesicles (CCVs). In order to better understand a possible role of post-translational modification of CALM (clathrin assembly protein lymphoid myeloid), the homologue of AP180, in the assembly of CCVs, CALM was expressed in the cell-free reticulocyte translation system that is capable of carrying out post-translational modification. The apparent molecular weight of the expressed recombinant CALM was estimated as 105 kD. Alkaline phosphatase treatment of CALM resulted in a mobility shift on SDS-PAGE. We found that CALM was associated with the proteins harboring SH3 domain, promote assembly of clathrin triskelia into clathrin cage and bound to the preformed clathrin cage. CALM was also proteolyzed by caspase 3 and calpain but not by caspase 8. These results indicated that the post-translationally modified CALM, expressed in the eukaryotic cell-free reticulocyte translation system was able to mediate the assembly of clathrin and the coated-vesicle formation.


Assuntos
Bovinos , Fosfatase Alcalina/farmacologia , Animais , Encéfalo/metabolismo , Calpaína/metabolismo , Proteínas de Transporte/química , Caspases/metabolismo , Sistema Livre de Células , Clatrina/química , Eletroforese em Gel de Poliacrilamida , Glutationa Transferase/metabolismo , Lipídeos/química , Proteínas de Membrana/química , Fosforilação , Ligação Proteica , Processamento de Proteína Pós-Traducional , Estrutura Terciária de Proteína , Transporte Proteico , Proteínas Recombinantes/química , Reticulócitos/metabolismo , Biossíntese de Proteínas , Domínios de Homologia de src
13.
Indian J Biochem Biophys ; 1993 Aug; 30(4): 209-13
Artigo em Inglês | IMSEAR | ID: sea-27667

RESUMO

Disulphide reduced and carboxymethylated riboflavin carrier protein (RCM-RCP), an unfolded derivative of chicken RCP, does not bind riboflavin and there is a drastic reduction in its ability to interact with antiserum to cRCP. Antibodies to RCM-RCP are directed against sequential epitopes(s). On radioiodination of RCM-RCP, a maximum of 30-50% binding at dilution of 1:500 was obtained with rabbit antibodies RCM-RCP [n = 5]. However, high titer antibodies was obtained when radioiodinated RCM-RCP was immobilized on ELISA microtiter plates suggesting that immobilization of RCM-RCP leads to either preservation of antigenic sites or improved presentation of the antigenic determinants. An avidin-biotin system was utilized to develop an ELISA.


Assuntos
Animais , Reações Antígeno-Anticorpo , Proteínas de Transporte/química , Galinhas , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos/análise , Feminino , Soros Imunes , Proteínas de Membrana Transportadoras , Metilação , Oxirredução , Riboflavina/metabolismo
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