Base de dados : MEDLINE
Pesquisa : D01.786 [Categoria DeCS]
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[PMID]:28465176
[Au] Autor:Nasabi M; Labbafi M; Mousavi ME; Madadlou A
[Ad] Endereço:Department of Food Science and Engineering, Razi Food Chemistry Lab, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran.
[Ti] Título:Effect of salts and nonionic surfactants on thermal characteristics of egg white proteins.
[So] Source:Int J Biol Macromol;102:970-976, 2017 Sep.
[Is] ISSN:1879-0003
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Effect of salts (Sodium chloride (NaCl), Sodium sulfate (Na SO ), Ammonium sulfate ((NH ) SO ), and nonionic surfactants (glycerol, tween20, tween80) on thermal properties of egg white proteins as a whole were investigated. Egg white solutions with additive (0, 0.5 and 1%) were collected after 0, 1 and 2min heat treatment. Physico-chemical properties of egg white proteins were evaluated by measuring heat coagulation time, solubility and turbidity of solution. Adding glycerol caused the most significant decrease in turbidity and increase in heat coagulation time and solubility of egg white, although Sodium Chloride had the least positive impact on physico-chemical properties of egg white under heat treatment. The Fourier transform infrared (FT-IR) spectroscopy analysis of heat treated egg white proteins as a whole with additives demonstrated changes in secondary protein structure, which are presented regarding the shape, intensity and position of FT-IR band. Meanwhile, it showed a good correlation with the physico-chemical properties consequences. Generally, the effect of nonionic surfactants were more noticeable than that of salts in preventing of egg white proteins aggregation under heat treatment. By improving thermal stability of egg white proteins, its usage in thermal processing industry can be evolved.
[Mh] Termos MeSH primário: Proteínas do Ovo/química
Sais/farmacologia
Tensoativos/farmacologia
Temperatura Ambiente
[Mh] Termos MeSH secundário: Animais
Agregados Proteicos/efeitos dos fármacos
Solubilidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Egg Proteins); 0 (Protein Aggregates); 0 (Salts); 0 (Surface-Active Agents)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE


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[PMID]:28466691
[Au] Autor:Guha M; Nguyen L; Poitout-Belissent F; Bedard A; Raman K
[Ad] Endereço:1 Medivation, Inc, San Francisco, CA, USA.
[Ti] Título:Salt Selection Matters: Differential Renal Toxicity With MDV1634.Maleate Versus MDV1634.2HCl.
[So] Source:Int J Toxicol;36(3):207-219, 2017 May/Jun.
[Is] ISSN:1092-874X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Salt forms of pharmaceutical compounds can have unique pharmacokinetic and toxicity properties. MDV1634 was evaluated for neurology indication and also demonstrated blood pressure (BP)-lowering effects in nonclinical studies. During the chemistry manufacturing campaign, 2 salt forms, dihydrochloride (2HCl) and maleate (MAL), which improved chemical stability and water solubility of the free base were identified. MDV1634.MAL showed better chemical attributes and was evaluated in toxicology studies for further development. A 28-day oral toxicity study in dogs with MDV1634.MAL demonstrated partially reversible renal toxicity. Although MAL salt is generally regarded as safe, renal toxicity is sometimes observed in rats and dogs. To evaluate contribution of each salt form to renal toxicity and BP lowering, an additional 28-day study was conducted with MDV1634.2HCL and MDV1634.MAL, which included toxicokinetics, continuous BP measurement in a subset of dogs, and sensitive urinary biomarker evaluation for temporal monitorability and reversibility of potential renal findings. In the repeat study, both salt forms showed similar exposures during the dosing period, but renal tubular toxicity was observed only with MDV1634.MAL and not with MDV1634.2HCl. The renal findings with MDV1634.MAL included early urinary biomarker changes (increase in albumin, clusterin, ß2 microglobulin, and neutrophil gelatinase-associated lipocalin); elevations in serum blood urea nitrogen and creatinine; and microscopic findings of partially reversible tubular basophilia, single cell necrosis, pigmentation, and mineralization. The renal findings in contrast to the BP findings were MAL-specific and considered not related to MDV1634, thereby under scoring the importance of salt forms in pharmaceutical development.
[Mh] Termos MeSH primário: Rim/efeitos dos fármacos
Maleatos/toxicidade
[Mh] Termos MeSH secundário: Animais
Pressão Sanguínea/efeitos dos fármacos
Cães
Feminino
Rim/patologia
Masculino
Maleatos/farmacocinética
Sais/farmacocinética
Sais/toxicidade
Testes de Toxicidade Subaguda
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Maleates); 0 (Salts)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180302
[Lr] Data última revisão:
180302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1177/1091581817704379


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[PMID]:29324339
[Au] Autor:Azzouz R; Peauger L; Gembus V; Tîntas ML; Sopková-de Oliveira Santos J; Papamicaël C; Levacher V
[Ad] Endereço:VFP Therapies, 15 rue François Couperin, 76000 Rouen, France.
[Ti] Título:Novel donepezil-like N-benzylpyridinium salt derivatives as AChE inhibitors and their corresponding dihydropyridine "bio-oxidizable" prodrugs: Synthesis, biological evaluation and structure-activity relationship.
[So] Source:Eur J Med Chem;145:165-190, 2018 Feb 10.
[Is] ISSN:1768-3254
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:As an extension of our previous work on donepezil-based "bio-oxidizable" prodrug approach, two new classes of N-benzylpyridinium donepezil analogues in tetralone B2 and acetophenone B3 series and a new set of indanone derivatives B1 were investigated along with the corresponding dihydropyridine prodrugs A1-3. A total of fifty one N-benzylpyridinium quaternary donepezil analogues B1-3 and twenty two prodrugs A1-3 were synthesized and evaluated for their inhibitory activities against hAChE and eqBuChE. While most prodrugs A1-3 were demonstrated to be inactive against AChE (IC > 10 µM), a large number of the corresponding N-benzylpyridinium salt B1-3 exhibited appealing three-to-one-digit nanomolar hAChE inhibitory activities and even reaching subnanomolar activity (IC = 0.36 nM). In addition, in silico docking studies were conducted for several compounds to explain the more relevant in vitro results. Lastly, the influence of the two stereogenic centers in prodrugs A was also evaluated, highlighting not only marked differences in residual AChE inhibitory activity of the four separated isomers of prodrug 23h (IC ranging from 173 nM to 10 µM) but also significant variations of the oxidation rate between two separated diastereoisomers of prodrug 24a. This work provides useful information in the search of a preclinical candidate to conduct further development of this attractive "bio-oxidizable" prodrug strategy.
[Mh] Termos MeSH primário: Acetilcolinesterase/metabolismo
Inibidores da Colinesterase/farmacologia
Di-Hidropiridinas/farmacologia
Pró-Fármacos/farmacologia
Compostos de Piridínio/farmacologia
[Mh] Termos MeSH secundário: Animais
Butirilcolinesterase/metabolismo
Inibidores da Colinesterase/síntese química
Inibidores da Colinesterase/química
Di-Hidropiridinas/química
Relação Dose-Resposta a Droga
Electrophorus
Cavalos
Simulação de Acoplamento Molecular
Estrutura Molecular
Pró-Fármacos/síntese química
Pró-Fármacos/química
Compostos de Piridínio/síntese química
Compostos de Piridínio/química
Sais/síntese química
Sais/química
Sais/farmacologia
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cholinesterase Inhibitors); 0 (Dihydropyridines); 0 (Prodrugs); 0 (Pyridinium Compounds); 0 (Salts); 7M8K3P6I89 (1,4-dihydropyridine); EC 3.1.1.7 (Acetylcholinesterase); EC 3.1.1.8 (Butyrylcholinesterase)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180227
[Lr] Data última revisão:
180227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180112
[St] Status:MEDLINE


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[PMID]:29297910
[Au] Autor:Pedreira-Segade U; Michot LJ; Daniel I
[Ad] Endereço:Univ Lyon, Ens de Lyon, Université Lyon 1, CNRS, UMR 5276 LGL-TPE, F-69342, Lyon, France. ulysse.pedreira@ens-lyon.org.
[Ti] Título:Effects of salinity on the adsorption of nucleotides onto phyllosilicates.
[So] Source:Phys Chem Chem Phys;20(3):1938-1952, 2018 Jan 17.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In the context of the origin of life, phyllosilicate surfaces might favor the adsorption, concentration and reactivity of otherwise diluted prebiotic molecules. The primitive oceanic seafloor was certainly rich in Fe-Mg-rich phyllosilicates. The salinity of the primitive seawater remains largely unknown. Values ranging from 1 to 15 times modern salinity have been proposed and the salt composition of the primitive ocean also remains elusive although it may have played a role in the interactions between nucleotides and mineral surfaces. Therefore we studied the adsorption of 5'-monophosphate deoxyguanosine (dGMP) as a model nucleotide onto a Fe-rich swelling clay, i.e. nontronite, and an Al-rich phyllosilicate, i.e. pyrophyllite, for comparison. Experiments were carried out at atmospheric pressure, 25 °C and natural pH, with a series of salts NaCl, MgCl , CaCl , MgSO , NaH PO and LaCl in order to evaluate the effect of cations and anions on dGMP adsorption. The present study shows that nucleotides are adsorbed on both phyllosilicates via a ligand exchange mechanism. The phosphate group of the nucleotide is adsorbed on the lateral metal hydroxyls of the broken edges of phyllosilicates. The presence of divalent cations or molecular anions, such as phosphate or sulfate, tends to inhibit this interaction on mineral surfaces. However, in the presence of divalent cations, cationic bridging on the basal surfaces of the swelling clay also occurs and could induce a higher retention capacity of the swelling clays compared to non-swelling phyllosilicates in primitive and modern natural environments.
[Mh] Termos MeSH primário: Silicatos de Alumínio/química
Nucleotídeos/química
[Mh] Termos MeSH secundário: Adsorção
Cátions Bivalentes/química
Nucleotídeos de Desoxiguanina/química
Concentração de Íons de Hidrogênio
Sais/química
Espalhamento a Baixo Ângulo
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Aluminum Silicates); 0 (Cations, Divalent); 0 (Deoxyguanine Nucleotides); 0 (Nucleotides); 0 (Salts); 1302-87-0 (clay); 7EAM4TG712 (2'-deoxyguanosine 5'-phosphate)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180104
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp07004g


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[PMID]:29406122
[Au] Autor:Wang X; Ma B; Bai Y; Lan H; Liu H; Qu J
[Ad] Endereço:Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
[Ti] Título:Comparison of the effects of aluminum and iron(III) salts on ultrafiltration membrane biofouling in drinking water treatment.
[So] Source:J Environ Sci (China);63:96-104, 2018 Jan.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Coagulation plays an important role in alleviating membrane fouling, and a noticeable problem is the development of microorganisms after long-time operation, which gradually secrete extracellular polymeric substances (EPS). To date, few studies have paid attention to the behavior of microorganisms in drinking water treatment with ultrafiltration (UF) membranes. Herein, the membrane biofouling was investigated with different aluminum and iron salts. We found that Al (SO ) ·18H O performed better in reducing membrane fouling due to the slower growth rate of microorganisms. In comparison to Al (SO ) ·18H O, more EPS were induced with Fe (SO ) ·xH O, both in the membrane tank and the sludge on the cake layer. We also found that bacteria were the major microorganisms, of which the concentration was much higher than those of fungi and archaea. Further analyses showed that Proteobacteria was dominant in bacterial communities, which caused severe membrane fouling by forming a biofilm, especially for Fe (SO ) ·xH O. Additionally, the abundances of Bacteroidetes and Verrucomicrobia were relatively higher in the presence of Al (SO ) ·18H O, resulting in less severe biofouling by effectively degrading the protein and polysaccharide in EPS. As a result, in terms of microorganism behaviors, Al-based salts should be given preference as coagulants during actual operations.
[Mh] Termos MeSH primário: Incrustação Biológica
Ferro/química
Sais/química
Purificação da Água/métodos
[Mh] Termos MeSH secundário: Alumínio
Ultrafiltração
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Salts); CPD4NFA903 (Aluminum); E1UOL152H7 (Iron)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180207
[St] Status:MEDLINE


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[PMID]:29253008
[Au] Autor:Milano T; Gulzar A; Narzi D; Guidoni L; Pascarella S
[Ad] Endereço:Dipartimento di Scienze biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, Italy.
[Ti] Título:Molecular dynamics simulation unveils the conformational flexibility of the interdomain linker in the bacterial transcriptional regulator GabR from Bacillus subtilis bound to pyridoxal 5'-phosphate.
[So] Source:PLoS One;12(12):e0189270, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:GabR from Bacillus subtilis is a transcriptional regulator belonging to the MocR subfamily of the GntR regulators. The structure of the MocR regulators is characterized by the presence of two domains: i) a N-terminal domain, about 60 residue long, possessing the winged-Helix-Turn-Helix (wHTH) architecture with DNA recognition and binding capability; ii) a C-terminal domain (about 350 residue) folded as the pyridoxal 5'-phosphate (PLP) dependent aspartate aminotransferase (AAT) with dimerization and effector binding functions. The two domains are linked to each other by a peptide bridge. Although structural and functional characterization of MocRs is proceeding at a fast pace, virtually nothing is know about the molecular changes induced by the effector binding and on how these modifications influence the properties of the regulator. An extensive molecular dynamics simulation on the crystallographic structure of the homodimeric B. subtilis GabR has been undertaken with the aim to envisage the role and the importance of conformational flexibility in the action of GabR. Molecular dynamics has been calculated for the apo (without PLP) and holo (with PLP bound) forms of the GabR. A comparison between the molecular dynamics trajectories calculated for the two GabR forms suggested that one of the wHTH domain detaches from the AAT-like domain in the GabR PLP-bound form. The most evident conformational change in the holo PLP-bound form is represented by the rotation and the subsequent detachment from the subunit surface of one of the wHTH domains. The movement is mediated by a rearrangement of the linker connecting the AAT domain possibly triggered by the presence of the negative charge of the PLP cofactor. This is the second most significant conformational modification. The C-terminal section of the linker docks into the "active site" pocket and establish stabilizing contacts consisting of hydrogen-bonds, salt-bridges and hydrophobic interactions.
[Mh] Termos MeSH primário: Bacillus subtilis/metabolismo
Proteínas de Bactérias/química
Proteínas de Bactérias/metabolismo
Simulação de Dinâmica Molecular
Fosfato de Piridoxal/metabolismo
Transativadores/química
Transativadores/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Ligação Proteica
Domínios Proteicos
Multimerização Proteica
Estrutura Secundária de Proteína
Subunidades Proteicas/química
Sais
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Protein Subunits); 0 (Salts); 0 (Trans-Activators); 5V5IOJ8338 (Pyridoxal Phosphate)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180108
[Lr] Data última revisão:
180108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189270


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[PMID]:28585343
[Au] Autor:Yuan XJ; Wen AY; Wang J; Desta ST; Dong ZH; Shao T
[Ad] Endereço:Institute of Ensiling and Processing of Grass, Nanjing Agricultural University, Nanjing, China.
[Ti] Título:Effects of four short-chain fatty acids or salts on fermentation characteristics and aerobic stability of alfalfa (Medicago sativa L.) silage.
[So] Source:J Sci Food Agric;98(1):328-335, 2018 Jan.
[Is] ISSN:1097-0010
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The objective of the present study was to evaluate the effects of four chemicals on the fermentation quality and aerobic stability of alfalfa (Medicago sativa L.) silage. Wilted alfalfa was ensiled without additive (control), or with formic acid (FA), potassium diformate (KDF), sodium diacetate (SDA) or calcium propionate (CAP). RESULTS: After 60 days of ensiling, the pH values in FA, KDF and SDA silages were lower (P < 0.05) compared to that of control and CAP silages, and chemicals (P < 0.05) decreased butyric acid and ammonia N concentrations and populations of aerobic bacteria and yeasts compared to the control. The SDA and CAP silages had a higher (P < 0.05) lactic acid bacteria content compared to the FA and KDF silages. The SDA and CAP silages had higher (P < 0.05) acetic and propionic acid contents compared to the other silages, respectively. The ammonia N concentrations in the FA and KDF silages were lower compared to the other silages during the first 5 days of aerobic exposure, and then increased sharply to 105 and 100 g kg total N, respectively, which was higher (P < 0.05) than that of the SDA and CAP silages on day 9 of aerobic exposure. Yeasts and aerobic bacteria counts in SDA silage slowly increased and remained at lower levels compared to the other silages after 7 days of aerobic exposure. CONCLUSION: Additives prolonged the aerobic stability duration compared to the control, and the SDA and CAP silages remained stable for more than 216 h, followed by the KDF and FA silages (202 and 196 h, respectively). © 2017 Society of Chemical Industry.
[Mh] Termos MeSH primário: Ácidos Graxos Voláteis/metabolismo
Lactobacillus/metabolismo
Medicago sativa/microbiologia
Sais/metabolismo
Silagem/análise
[Mh] Termos MeSH secundário: Aerobiose
Ácidos Graxos Voláteis/química
Fermentação
Medicago sativa/química
Propionatos/metabolismo
Silagem/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fatty Acids, Volatile); 0 (Propionates); 0 (Salts); 8AI80040KW (calcium propionate); JHU490RVYR (propionic acid)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171228
[Lr] Data última revisão:
171228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170607
[St] Status:MEDLINE
[do] DOI:10.1002/jsfa.8475


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[PMID]:29148294
[Au] Autor:Xie X; Cong W; Zhao F; Li H; Xin W; Hou G; Wang C
[Ad] Endereço:a School of Pharmacy, the Key Laboratory of Prescription Effect and Clinical Evaluation of State Administration of Traditional Chinese Medicine of China , Binzhou Medical University , Yantai , P. R. China.
[Ti] Título:Synthesis, physiochemical property and antimicrobial activity of novel quaternary ammonium salts.
[So] Source:J Enzyme Inhib Med Chem;33(1):98-105, 2018 Dec.
[Is] ISSN:1475-6374
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Twenty-four novel 5-phenyl-1,3,4-oxadiazole-2-thiol (POT) analogues, benzo[d]oxazole-2-thiol, benzo[d]thiazole-2-thiol and 5-methyl-1,3,4-thiadiazole-2-thiol-substituted N,N-bis(2-hydroxyethyl) quaternary ammonium salts (QAS) (5a-d, 6a-d, 7a-d, 10a-d, 13a-d, 16a-d) were prepared and characterised by FTIR, NMR and elemental analysis. Part of target compounds (5d, 6d, 7d, 10d, 13d, 16d) displayed potent antimicrobial effect against ten common pathogens (S. aureus, α-H-tococcus, ß-H-tococcus, E. coli, P. aeruginosa, Proteus vulgaris, Canidia Albicans, Cytospora mandshurica, Physalospora piricola, Aspergillus niger) and had relatively low cytotoxity against two human cell lines (HaCat and LO2). TEM and SEM images of E. coli and S. aureus morphologies treated with 7d showed that the antibacterial mechanism might be the QAS fixing on cell wall surfaces and puncturing to result in the release of bacterial cytoplasm. This study provides new information of QAS, which could be used to design novel antimicrobial agents applied in clinic or agriculture.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Antifúngicos/farmacologia
Bactérias/efeitos dos fármacos
Fungos/efeitos dos fármacos
Compostos de Amônio Quaternário/farmacologia
[Mh] Termos MeSH secundário: Antibacterianos/química
Antifúngicos/química
Linhagem Celular
Sobrevivência Celular/efeitos dos fármacos
Parede Celular/efeitos dos fármacos
Química Física
Relação Dose-Resposta a Droga
Seres Humanos
Testes de Sensibilidade Microbiana
Estrutura Molecular
Compostos de Amônio Quaternário/química
Sais/química
Sais/farmacologia
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Antifungal Agents); 0 (Quaternary Ammonium Compounds); 0 (Salts)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171118
[St] Status:MEDLINE
[do] DOI:10.1080/14756366.2017.1396456


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[PMID]:28934270
[Au] Autor:Laut L; Martins MVA; Frontalini F; Ballalai JM; Belart P; Habib R; Fontana LF; Clemente IMMM; Lorini ML; Mendonça Filho JG; Laut VM; Figueiredo MSL
[Ad] Endereço:Laboratório de Micropaleontologia - LabMicro, Universidade Federal do Estado do Rio de Janeiro - UNIRIO, Rio de Janeiro, Rio de Janeiro, Brazil.
[Ti] Título:Assessment of the trophic state of a hypersaline-carbonatic environment: Vermelha Lagoon (Brazil).
[So] Source:PLoS One;12(9):e0184819, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Vermelha Lagoon is a hypersaline shallow transitional ecosystem in the state of Rio de Janeiro (Brazil). This lagoon is located in the protected area of Massambaba, between the cities of Araruama and Saquarema (Brazil), and displays two quite uncommon particularities: it exhibits carbonate sedimentation and displays the development of Holocene stromatolites. Due to both particularities, the salt industry and property speculation have been, increasingly, generating anthropic pressures on this ecosystem. This study aims to apply a multiproxy approach to evaluate the trophic state of Vermelha Lagoon based on physicochemical parameters and geochemical data for the quantification and qualification of organic matter (OM), namely total organic carbon (TOC), total sulfur (TS), total phosphorus (TP) and biopolymeric carbon (BPC), including carbohydrates (CHO), lipids (LIP) and proteins (PTN). The CHO/TOC ratio values suggest that OM supplied to the sediment is of autochthonous origin and results, essentially, from microbial activity. The cluster analyses allowed the identification of four regions in Vermelha Lagoon. The Region I included stations located in shallow areas of the eastern sector of Vermelha lagoon affected by the impact of the artificial channel of connection with Araruama Lagoon. The Region II, under the influence of salt pans, is characterized by the highest values of BPC, namely CHO promoted by microbiological activity. The Region III include stations spread through the lagoon with high values of dissolved oxygen and lower values of TP. Stromatolites and microbial mattes growth was observed in some stations of this sector. Region IV, where the highest values of TOC and TS were found, represents depocenters of organic matter, located in general in depressed areas. Results of this work evidences that the Vermelha Lagoon is an eutrophic but alkaline and well oxygenated environment (at both water column and surface sediment) where the autotrophic activity is greater than heterotrophic one. These particular conditions make this a special and rare ecosystem.
[Mh] Termos MeSH primário: Ecossistema
Sedimentos Geológicos/química
Águas Salinas/química
[Mh] Termos MeSH secundário: Processos Autotróficos
Brasil
Carboidratos/química
Carbono/química
Análise por Conglomerados
Sedimentos Geológicos/microbiologia
Concentração de Íons de Hidrogênio
Lipídeos/química
Oxigênio/química
Fósforo/química
Proteínas/química
Sais/química
Enxofre/química
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Carbohydrates); 0 (Lipids); 0 (Proteins); 0 (Salts); 27YLU75U4W (Phosphorus); 70FD1KFU70 (Sulfur); 7440-44-0 (Carbon); S88TT14065 (Oxygen)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170922
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0184819


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[PMID]:28834716
[Au] Autor:Purohit A; England JK; Douma LG; Tondnevis F; Bloom LB; Levitus M
[Ad] Endereço:School of Molecular Sciences and Biodesign Institute, Arizona State University, Tempe, Arizona.
[Ti] Título:Electrostatic Interactions at the Dimer Interface Stabilize the E. coli ß Sliding Clamp.
[So] Source:Biophys J;113(4):794-804, 2017 Aug 22.
[Is] ISSN:1542-0086
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Sliding clamps are ring-shaped oligomeric proteins that encircle DNA and associate with DNA polymerases for processive DNA replication. The dimeric Escherichia coli ß-clamp is closed in solution but must adopt an open conformation to be assembled onto DNA by a clamp loader. To determine what factors contribute to the stability of the dimer interfaces in the closed conformation and how clamp dynamics contribute to formation of the open conformation, we identified conditions that destabilized the dimer and measured the effects of these conditions on clamp dynamics. We characterized the role of electrostatic interactions in stabilizing the ß-clamp interface. Increasing salt concentration results in decreased dimer stability and faster subunit dissociation kinetics. The equilibrium dissociation constant of the dimeric clamp varies with salt concentration as predicted by simple charge-screening models, indicating that charged amino acids contribute to the remarkable stability of the interface at physiological salt concentrations. Mutation of a charged residue at the interface (Arg-103) weakens the interface significantly, whereas effects are negligible when a hydrophilic (Ser-109) or a hydrophobic (Ile-305) amino acid is mutated instead. It has been suggested that clamp opening by the clamp loader takes advantage of spontaneous opening-closing fluctuations at the clamp's interface, but our time-resolved fluorescence and fluorescence correlation experiments rule out conformational fluctuations that lead to a significant fraction of open states.
[Mh] Termos MeSH primário: DNA Polimerase III/química
DNA Polimerase III/metabolismo
Escherichia coli/enzimologia
Multimerização Proteica
Eletricidade Estática
[Mh] Termos MeSH secundário: DNA Polimerase III/genética
Relação Dose-Resposta a Droga
Concentração de Íons de Hidrogênio
Mutação
Estabilidade Proteica/efeitos dos fármacos
Estrutura Quaternária de Proteína
Sais/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Salts); EC 2.7.7.- (DNA Polymerase III); EC 2.7.7.- (beta subunit, DNA polymerase III)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170907
[Lr] Data última revisão:
170907
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170824
[St] Status:MEDLINE



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