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1.
Org Biomol Chem ; 16(23): 4272-4278, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29796570

RESUMO

Controlling S-nitrosothiol decomposition, with the consequent release of nitric oxide, is a topic of great research interest. The incorporation of nitrosomercaptopyridine (SNO+) into the cucurbit[7]uril cavity results in a large increase of its nitrosation equilibrium constant. This effect being a consequence of the preferential stabilization of organic cations by the formation of host : guest complexes with CB7 results in a drastic reduction of the SNO+ denitrosation rate constant. Moreover, SNO+ encapsulation also prevents its decomposition yielding disulfide and nitric oxide. The expulsion of SNO+ from the cucurbituril cavity through the application of a chemical stimulus (competitive binding) results in controlled nitric oxide release as was confirmed by using a NO selective electrode.

3.
Mol Phylogenet Evol ; 61(3): 888-98, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21872668

RESUMO

Delimiting species is a crucial issue for many biological disciplines and is of primary importance for designing effective conservation plans. Traditional taxonomy based on morphological characters can be misled by the presence of phenotypic plesiomorphism or adaptative convergence. The use of multiple locus genetic data appears thus as a powerful tool for recognizing species boundaries. In this study, we used six nuclear introns and two mitochondrial markers to conduct a phylogenetic study of the Myotis nattereri species complex in the Western Palearctic. We combined tree-based and non-tree-based analyses, and also used concatenated phylogenetic methods of the separated nuclear and mitochondrial dataset as well as a recent coalescence-based multilocus approach. The strong concordance between the results of the analyses conducted confirms that M. nattereri is a paraphyletic group that is composed of four well-differentiated lineages in the study area. In the framework of the unified species concept, these four clades can be confidently considered as four valid species. This recognition of new cryptic species in the Western Mediterranean region shows that the biodiversity of this well-studied area is still not fully understood.


Assuntos
Quirópteros/genética , Loci Gênicos/genética , Filogenia , Alelos , Animais , Regiões Árticas , Teorema de Bayes , Núcleo Celular/genética , Análise por Conglomerados , Marcadores Genéticos , Geografia , Íntrons/genética , Região do Mediterrâneo , Mitocôndrias/genética , Dinâmica Populacional , Análise de Sequência de DNA , Software , Especificidade da Espécie
4.
J Phys Chem B ; 113(19): 6749-55, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19378985

RESUMO

In this contribution the influence of beta-cyclodextrin (CD) on the behavior of aqueous systems containing vesicles of dipalmitoyl phosphatidyl choline (DPPC) has been studied by determining the kinetics of the solvolysis reaction of substituted benzoyl chlorides whose solvolysis reactivity entails a high sensitivity on media properties. The application of the pseudophase formalism allowed us to obtain the thermodynamic and kinetic coefficients characteristic of the reaction, which are essentially independent of the concentration of CD. We were able to determine the percentages of uncomplexed cyclodextrin in equilibrium with the vesicular system which were in all cases compatible with 100%. The obtained results led us to conclude that the properties of DPPC vesicles are not affected by the presence of CD in the medium and there is no type of interaction between the CD and the vesicular surfactant monomers and, therefore, all cyclodextrin is present in the mixed system as uncomplexed cyclodextrin.


Assuntos
Benzoatos/química , Ciclodextrinas/química , Membranas Artificiais , Solventes/química , 1,2-Dipalmitoilfosfatidilcolina/química , Cinética , Água/química
5.
Heredity (Edinb) ; 103(2): 178-87, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19401715

RESUMO

The meridional serotine bat Eptesicus isabellinus is found in North Africa and the Iberian Peninsula. We analyzed the genetic structure of E. isabellinus at two different geographic scales to reveal the historical and ecological patterns that have shaped its populations. The role of the Straits of Gibraltar as an isolating barrier between African and Iberian populations is evaluated and the degree of genetic structure and female-mediated gene flow was assessed at a local scale between neighboring colonies. Populations of E. isabellinus from Iberia and northern Morocco show little genetic divergence and share mtDNA haplotypes, indicating that the Straits of Gibraltar are neither an impediment to dispersal nor a cause of genetic differentiation. Our results also suggest that E. isabellinus may have dispersed from western Andalusia into northern Morocco after the last glacial period. At a smaller geographic scale, the colonies studied showed high variation in genetic variability and structure, indicating that no female-mediated gene flow is present. This pattern is consistent with a described pattern of independent endemic viral circulation of the bat rabies virus EBLV-1, which was found when studying rabies dynamics in the same serotine bat colonies.


Assuntos
Quirópteros/genética , DNA Mitocondrial/genética , África do Norte , Animais , Genética Populacional , Gibraltar , Região de Controle de Locus Gênico , Espanha
6.
Nanotechnology ; 20(9): 095708, 2009 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-19417504

RESUMO

In this work we compare the standard imaging of various types of nanoparticles deposited on surfaces by atomic force microscopy (AFM) with a complementary analysis of the same samples by either electrostatic force microscopy (EFM) or magnetic force microscopy (MFM). Experiments were carried out on gold nanoparticles (decahedrons and stars) and two different iron oxide systems: goethite (alpha-FeOOH) and hematite (alpha-Fe(2)O(3)). Regardless of the particular geometry, the EFM signal appears to be stronger on edges or tips of pure gold nanoparticles. Both EFM and MFM experiments were also carried out on iron oxide particles. Apart from the structural analysis, we analyzed the influence of a shell layer deposited on the gold and iron oxide particles, the shell being amorphous SiO(2). Although the silica layer was found to have an insulating effect around the particles, in all cases EFM/MFM measurements could still be performed by the proper choice of the scan lift height (with an eventual slight increase of the sample bias, where applicable).


Assuntos
Cristalização/métodos , Microscopia de Força Atômica/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
7.
Dev Biol (Basel) ; 131: 311-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18634493

RESUMO

Different rhabdoviruses have been found in healthy bats, suggesting asymptomatic infection. The aim of this study was to focus on the epidemiology and pathogenesis of EBLV1 infection in the meridional serotine bat (Eptesicus isabellinus), as well as to search for other rhabdoviruses in this bat, which is the responsible for more than 95% of cases of human exposure to lyssaviruses in Europe. RT-PCR on oropharyngeal swabs was used together with antibody detection by the Rapid Fluorescent Focus Inhibition Test (RFFIT) to investigate EBLV1 circulation in 19 natural colonies of meridional serotine bats in Andalusia (Spain) from 1998 to 2003. The survey was based on 1,227 different captures of 1,033 individuals that were ring banded, sampled and released. Individuals that were repeatedly captured were always found in the same colony, despite the fact that some colonies were less than five km apart. Viral circulation was detected in ten colonies either by RT-PCR, serology or both. Each colony showed a different temporal pattern of viral circulation suggesting independent endemic circulation. Some positive individuals were captured healthy in following campaigns providing evidence for survival after viral infection. RNA from two apparently new Dimarhabdoviruses was also found in the pharyngeal cavity of two healthy bats.


Assuntos
Quirópteros/virologia , Lyssavirus/isolamento & purificação , Infecções por Rhabdoviridae/veterinária , Animais , Animais Selvagens , Lyssavirus/classificação , Lyssavirus/imunologia , Orofaringe/virologia , RNA Viral/química , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Infecções por Rhabdoviridae/diagnóstico , Infecções por Rhabdoviridae/epidemiologia , Infecções por Rhabdoviridae/virologia , Espanha/epidemiologia
8.
J Genet ; 97(5): 1179-1183, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30555067

RESUMO

Pteronotus psilotis, a mormoopid bat, is an insectivorous, gregarious and strict cave-dwelling species that is found areas between the sea level and an elevation of about 1000 masl. This species is present in diverse habitats ranging from rain forest to dry deciduous forest. Nine microsatellite loci were developed for Wagner's mustached bat, Pteronotus psilotis using the next-generation sequencing approach, and their utility for population genetics studies was assessed. All loci were polymorphic (7-15 alleles) and characterized in 30 individuals from three P. psilotis populations, with the levels of observed and expected heterozygosity ranging from 0.280 to 0.867 and 0.584 to 0.842, respectively. One locus showed significant departures from Hardy-Weinberg expectations after Bonferroni correction. Cross-amplification in 11 other bat species was tested, for which eight microsatellites were successfully amplified, and of these seven were polymorphic. The development of these new microsatellite loci will contribute to investigations of genetic population structure, genetic diversity and gene flow in P. psilotis populations, as well as in other closely related bat species.


Assuntos
Quirópteros/classificação , Quirópteros/genética , DNA/análise , Repetições de Microssatélites , Animais , DNA/genética , Especificidade da Espécie
10.
J Phys Chem B ; 110(16): 8524-30, 2006 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-16623541

RESUMO

A systematic study on the solvolysis reaction of substituted benzoyl chlorides in the presence of zwitterionic vesicles of dipalmitoyl phosphatidylcholine (DPPC) has been performed. Size, shape, surface charge, and polarity of the interface of the vesicular aggregates were determined using various techniques. The application of the pseudophase formalism allowed us to obtain the thermodynamic and kinetic coefficients characteristic of the reaction. The effects of vesicular aggregates on the solvolysis of benzoyl chlorides, which are known to be sensitive to the physical properties of the medium, depend on the nature of the substrate. For benzoyl chlorides with electron-donating groups, which react predominantly through a dissociative mechanism which is strongly affected by medium properties, the rate constant decreases as the vesicle concentration increases. On the other hand, for benzoyl chlorides with electron-withdrawing groups, which react mainly via an associative pathway, DPPC vesicles catalyze the solvolysis reaction.

11.
J Phys Chem B ; 110(32): 15831-8, 2006 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-16898733

RESUMO

The chemical behavior of beta-cyclodextrin/nonionic surfactant mixed systems has been investigated using the basic hydrolysis of N-methyl-N-nitroso-p-toluenesulfonamide as a chemical probe. The experimental results prove that at the cmc, there are significant quantities of uncomplexed beta-CD in equilibrium with the micellar aggregates. In contrast to the expected situation, the percentage of uncomplexed beta-CD in equilibrium with the micellar system increases on increasing the hydrophobicity of the surfactant molecule. This behavior is due to the existence of two simultaneous processes: complexation of surfactant monomers by cyclodextrin and the process of self-assembly to form micellar aggregates. The autoaggregation of surfactant monomers is expected to be more important than the complexation process in this mixed system. Varying the hydrophobicity of the surfactant monomer enabled us to determine that the percentages of uncomplexed cyclodextrin in equilibrium with the micellar system were in the range of 5-95%.


Assuntos
Micelas , beta-Ciclodextrinas/química , Hidrólise , Estrutura Molecular , Sulfonamidas/química , Tensão Superficial , Tensoativos/química
12.
Dev Biol (Basel) ; 125: 257-61, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16878483

RESUMO

The serotine bat (Eptesicus serotinus) accounts for 95 % of cases of human exposition to EBLV1. The aim of this study was to focus on the epidemiology and pathogenesis of EBLV1 infection in the serotine bat. Our first objective was the development of an RT-PCR technique for the specific detection of EBLV1 RNA in oro-pharyngeal swabs. This technique showed better performance than the classical immunofluorescence (IF) on brain in detecting EBLV1 in healthy flying bats. We have used this technique together with antibody detection by the fluorescent focus inhibition test (FFIT) to investigate EBLV1 circulation in 19 natural colonies of serotine bats in Andalusia (Spain) from 1998 to 2003. The survey was based on 1223 different captures of 1080 individuals that were ring banded, sampled and released. Individuals that were repeatedly captured were always found in the same colony even though some colonies were less than five Km apart. Viral circulation was detected in nine colonies either by RT-PCR, serology or both. Each colony showed a different temporal pattern of viral circulation suggesting independent endemic circulation. Some positive individuals were captured healthy in following campaigns evidencing survival after viral infection.


Assuntos
Quirópteros/virologia , Lyssavirus , Infecções por Rhabdoviridae/virologia , Animais , Encéfalo/virologia , Estudos Longitudinais , Lyssavirus/genética , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Infecções por Rhabdoviridae/genética , Infecções por Rhabdoviridae/transmissão , Espanha
13.
Nanoscale ; 8(8): 4557-64, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26822759

RESUMO

Here we describe the first seedless synthesis of vinyl-terminated Au nanotriangular prisms (AuNTPs) and nanooctahedra (AuNOC) in aqueous media. This synthesis is performed by chemical reduction of chloroauric acid (HAuCl4) with 3-butenoic acid (3BA) in the presence of benzyldimethylammonium chloride (BDAC). The principal novelties of the presented method are the use of a mixture of 3BA and BDAC, the synthesis of gold prisms and octahedra with controllable size, and the presence of terminal double bonds on the metal surface. Initially this method produces a mixture of triangular gold nanoprisms and octahedra; however, both morphologies are successfully separated by surfactant micelle induced depletion interaction, reaching percentages up to ∼90%. Moreover, the alkene moieties present on the gold surface are exploited for the fabrication of hybrid core@shell particles. Gold octahedra and triangular prisms are easily encapsulated by free radical polymerization of N-isopropylacrylamide (NIPAM). Finally, in order to obtain a gold core with the most number of tips, AuNTP@pNIPAM microgels were subjected to gold core overgrowth, thus resulting in star-shaped nanoparticles (AuSTs@pNIPAM). We use 4-amino-benzenethiol as the model analyte for SERS investigations. As expected, gold cores with tips and high curvature sites produced the highest plasmonic responses.

14.
J Phys Chem B ; 109(47): 22614-22, 2005 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16853944

RESUMO

The solvolysis reactivity of benzoyl chlorides entails a high sensitivity on medium properties. A systematic study of the reaction of a series of these substrates, varying the electron-withdrawing character of the substituent, has been performed in nonionic microemulsions. The kinetic effects due to variation of microemulsion compositions can be assigned to modifications in system properties, to be precise, to modifications in interface properties. Microemulsion properties that are obtained from kinetic analysis of solvolysis show a good agreement with the characterization of the microemulsion that was made via 1H NMR and solvatochromic fluorescence probes. Benzoyl chlorides with electron-donating groups react through a dissociative mechanism, whereas electron-withdrawing groups favor an associative mechanism. A comparative analysis of reactivity between the different substrates at the interface shows a variation in the contributions of both reaction pathways, associative and dissociative, to the whole reaction mechanism. The confined media shift the point where the mechanism changes from an associative to a dissociative pathway, far away from the turning point in water. Furthermore, the change in mechanism can be modulated by modification of the microemulsion composition.

15.
Cancer Epidemiol Biomarkers Prev ; 8(2): 159-66, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10067814

RESUMO

To choose a sensitive protocol to discriminate populations exposed and not exposed to inducers, five urinary metabolite ratios (MRs) [MR1 (17X + 17U)/137X, MR2 (5-acetylamino-6-formylamino-3-methyluracil [AFMU] + 1X + 1U)/17U, MR3 (17X/137X), MR4 (AFMU + 1X + 1U + 17X + 17U)/137X, and MR5 (AFMU + 1X + 1U)/17X] were calculated in 4-5 h and 0-24 h urine samples after caffeine intake. One hundred twenty-five healthy volunteers (59 nonsmokers and 66 smokers) were included in the study. All ratios showed a log-normal distribution. MR2 in the two time intervals was the only ratio nondependent on the urine flow. Differences between nonsmokers and smokers could be detected with all ratios at 4-5 h. However, only MR2 and, to a lesser extent, MR5 allowed the discrimination of higher cytochrome P450 1A2 (CYP1A2) activity in smokers in the 0-24 h sample. Although smokers had increased urinary mutagenicity in relation to nonsmokers, a significant association between MRs and urine mutagenicity was observed only with MR2 in the 4-5 h interval; this ratio/time schedule being that of higher association with tobacco consumption. The most flow-dependent ratios, MR1, MR3, and MR4, were closely correlated with each other at the two intervals. The flow dependency profile of each ratio may explain their different power to indicate both tobacco exposure and tobacco-derived mutagenicity. In conclusion, MR2 in the period of 4-5 h after caffeine intake seems preferable, especially at high urine flow rates.


Assuntos
Cafeína/urina , Estimulantes do Sistema Nervoso Central/urina , Citocromo P-450 CYP1A2/metabolismo , Mutagênicos/farmacologia , Fumar/metabolismo , Micção , Adolescente , Adulto , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Exposição Ambiental , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reologia , Fumar/urina , Teofilina/urina , Fatores de Tempo , Uracila/análogos & derivados , Uracila/urina , Ácido Úrico/análogos & derivados , Ácido Úrico/urina , Xantinas/urina
16.
Org Lett ; 2(2): 127-30, 2000 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-10814263

RESUMO

[reaction: see text] We have analyzed the different catalytic effects of surfactant aggregates upon the rate-determining hydroxide ion induced deprotonation reaction of 1. Vesicles are more effective catalysts than micelles, most likely providing a more apolar microenvironment at the substrate binding sites. We suggest that this leads to a catalytic reaction involving less strongly hydrated hydroxide ions. In the case of DODAB and DODAC vesicles, binding of cholesterol to the bilayer further increases the catalytic efficiency.


Assuntos
Lipossomos/farmacologia , Prótons , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Carbono/química , Catálise/efeitos dos fármacos , Colesterol/farmacologia , Cinética , Lipossomos/química , Micelas , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Tensoativos/química , Tensoativos/farmacologia
17.
Rev Neurol ; 34 Suppl 1: S148-50, 2002 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-12447807

RESUMO

The child's rehabilitation objectives are the same of the early intervention. The early intervention include motor approaches to facilitate the unique way of the newborn's expression: the movement and with it his holistic development. The motor approach is a classic aspect of early intervention but it is not itself early intervention. When the treatment objective is a term or preterm newborn or neonate the motor approach may be the principal method to facilitate perceptions experiences and basic habits. This intervention is not made with a specific physiotherapeutic technique. It is a sequential stimulation or development, without forget that the child must be taken as a whole. This point of view has special importance the first days of life and must be included in perinatal approach routines. In this paper we expose the work method of a Child Rehabilitation Team liked to a Newborn Unit.


Assuntos
Intervenção Educacional Precoce/métodos , Transtornos dos Movimentos/terapia , Modalidades de Fisioterapia , Feminino , Humanos , Lactente , Recém-Nascido , Equipe de Assistência ao Paciente , Estimulação Física , Gravidez , Cuidado Pré-Natal
18.
An Med Interna ; 15(7): 353-7, 1998 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-9710984

RESUMO

BACKGROUND: Community-acquired pneumonia (CAP) frequently determines inpatient treatment and has a high mortality. It is desirable to know which factors predicts a favorable outcome of elderly patients with CAP. This fact could allow that a growing number of patients could be treated in their home. OBJECTIVE: To investigate the variables related with the survival of hospitalized elderly patients for with CAP. METHODS: We carried out a retrospective study of 158 patients aged more than 65 years, that were admitted to our hospital for CAP. RESULTS: Mean age was 80.3 +/- 8.2 years (66-98 years). Eighty nine (56%) patients were men and 69 (44%) were women. Twenty seven patients (17%) died during their stay in the hospital. By multivariate analysis, independent variables associated with survival were: confusion (p = 0.0001), treatment with H2 receptor antagonists (p = 0.01), respiratory frequency (above 30 per minute, p = 0.01) and arterial pH (below 7.40, p = 0.03). Sensibility and specificity about prediction of survival in elderly patients with PAC who hadn't any variables above pointed out were 0.89 and 0.64, respectively. CONCLUSIONS: Application of this results could help physicians make decisions about hospitalization for elderly patients with PAC.


Assuntos
Idoso , Pneumonia/mortalidade , Fatores Etários , Idoso de 80 Anos ou mais , Infecções Comunitárias Adquiridas/complicações , Infecções Comunitárias Adquiridas/mortalidade , Feminino , Hospitalização , Humanos , Masculino , Análise Multivariada , Pneumonia/complicações , Prognóstico , Estudos Retrospectivos
20.
Mol Ecol Resour ; 9(3): 1044-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-21564834

RESUMO

Ten novel polymorphic microsatellite loci were isolated and characterized from the Balearic shearwater (Puffinus mauretanicus), a critically endangered seabird. The developed loci revealed a relatively low number of alleles per locus, as well as low levels of polymorphism (H(O)  = 0.377 ± 0.241). One of the loci appeared to be W-linked. All polymorphic loci were successfully amplified in its closely related species, the Yelkouan shearwater (Puffinus yelkouan). These microsatellite markers would be useful for assessing population structure in the Balearic shearwater and the possible hybridization process between both shearwaters species.

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