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1.
J Endocrinol Invest ; 45(10): 1977-1990, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35718853

RESUMO

OBJECTIVES: Graves' disease induced by Alemtuzumab (GD-IA) is one of the most frequently observed adverse events in patients with multiple sclerosis (MS) treated with this drug. The aim of this study is the sequencing and description of these events, along with the identification of the risk factors leading to their development. MATERIALS AND METHODS: We conducted a retrospective observational study identifying patients with relapsing-remitting multiple sclerosis (RRMS) and GD-IA, studying their baseline clinical features and variables related to the natural history of the disease. RESULTS: A total of 121 participants treated with Alemtuzumab were included, of whom 41 developed GD-IA (33.9%). A higher percentage of first-degree relatives with autoimmune thyroid disease was documented in the subgroup who developed the abovementioned event (14.6% vs 1.5%; p < 0.01). A total of 70.7% of patients diagnosed with GD-IA (n = 29/41) had fluctuations in thyroid function during follow-up, and 24.4% (n = 10/41) required total thyroidectomy for resolution of the condition. In 54.8% of participants diagnosed with GD-IA, a pattern of significant TSH decline was identified in the month prior to diagnosis of the event, with high predictive ability and associated with a more favorable clinical course (fewer weeks to normalization of thyroid function, HR = 8.99; 95% CI [2.11-38.44]; p = 0.0003). CONCLUSION: GD-IA has an atypical course compared to classical forms of the disease. The identification of risk factors for the development of the disease before starting treatment with Alemtuzumab and early monitoring of thyroid function once this treatment is initiated prove to be useful strategies in the diagnosis and clinical management of this condition.


Assuntos
Doença de Graves , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Alemtuzumab/efeitos adversos , Doença de Graves/induzido quimicamente , Doença de Graves/tratamento farmacológico , Humanos , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Tireoidectomia
2.
Sci Rep ; 11(1): 15161, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34312431

RESUMO

As the south-westernmost region of Europe, the Iberian Peninsula stands as a key area for understanding the process of modern human dispersal into Eurasia. However, the precise timing, ecological setting and cultural context of this process remains controversial concerning its spatiotemporal distribution within the different regions of the peninsula. While traditional models assumed that the whole Iberian hinterland was avoided by modern humans due to ecological factors until the retreat of the Last Glacial Maximum, recent research has demonstrated that hunter-gatherers entered the Iberian interior at least during Solutrean times. We provide a multi-proxy geoarchaeological, chronometric and paleoecological study on human-environment interactions based on the key site of Peña Capón (Guadalajara, Spain). Results show (1) that this site hosts the oldest modern human presence recorded to date in central Iberia, associated to pre-Solutrean cultural traditions around 26,000 years ago, and (2) that this presence occurred during Heinrich Stadial 2 within harsh environmental conditions. These findings demonstrate that this area of the Iberian hinterland was recurrently occupied regardless of climate and environmental variability, thus challenging the widely accepted hypothesis that ecological risk hampered the human settlement of the Iberian interior highlands since the first arrival of modern humans to Southwest Europe.


Assuntos
Migração Humana/história , Animais , Arqueologia , Teorema de Bayes , Carvão Vegetal/história , Clima , Meio Ambiente , Fósseis/história , Sedimentos Geológicos/análise , Fenômenos Geológicos , História Antiga , Humanos , Modelos Biológicos , Pólen/química , Dinâmica Populacional/história , Datação Radiométrica , Espanha , Vertebrados , Madeira/história
3.
J Small Anim Pract ; 61(9): 547-553, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32716068

RESUMO

OBJECTIVES: Preliminary evaluation of the efficacy of two commercial ear solutions composed of (1) chlorhexidine-Tris-ethylenediaminetetraacetic acid (EDTA) or (2) medical grade honey, for the treatment of otitis externa in dogs. MATERIALS AND METHODS: Dogs affected with otitis externa housed in an animal shelter were eligible for inclusion. Treatment was applied daily for 10 days and effect was measured by otitis clinical scores and microbiological counts. One of the treatments was applied to affected left ears, while the other was applied to affected right ears. RESULTS: A total of 24 ears from 13 dogs were included in the study. During the treatment period, with both treatments it was observed an improvement in clinical scores and a decrease in microbiological counts. At the end of the study 22 of 24 ears were deemed to have mild (4 ears), or no (18 ears) pain, with only two ears still showing pruritus. CLINICAL SIGNIFICANCE: The application of ear solutions composed of chlorhexidine-Tris-EDTA or medical grade honey, in the absence of antimicrobial treatment, might be effective for the control of clinical signs and microbial colonisation in dogs with otitis externa. Additional randomised studies on clinical patients are required to validate these findings.


Assuntos
Doenças do Cão , Mel , Otite Externa , Animais , Antibacterianos/uso terapêutico , Clorexidina , Doenças do Cão/tratamento farmacológico , Cães , Otite Externa/tratamento farmacológico , Otite Externa/veterinária
4.
Appl Opt ; 59(13): D201-D209, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400643

RESUMO

Mixed-halide organic-inorganic hybrid perovskites are considered promising light-absorbing materials in the development of solar cells related to the obtained high-power conversion efficiency. Current efforts are focused on the study of the energy-conversion mechanisms, where the nonradiative recombination pathway is the least explored. In this work, a combination of optical and photoacoustic spectroscopies is used to determine the visible spectral light-into-heat conversion efficiency of lead-based mixed-halide organic-inorganic hybrid perovskites in a semicomplete n-i-p mesoscopic perovskite solar cell (PSC). A remarkable average conversion efficiency of about 87% has been found for the nonradiative combination in the perovskite, with the estimated composition ${{\rm FA}_{0.71}}{{\rm MA}_{0.29}}{{\rm PbI}_{2.9}}{{\rm Br}_{0.1}}$FA0.71MA0.29PbI2.9Br0.1 in the wavelength range of 400 to 800 nm. As a result, 13% of the incident light is transformed in radiative recombination processes and/or photodegradation of the material. Furthermore, the extinction coefficient and refractive index of the material are reported, and it was found that the optical constants and the optical absorption in the short-wavelength range are significantly smaller than previously reported for${{\rm MAPbI}_3}$MAPbI3.

5.
Bioelectrochemistry ; 126: 1-11, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30471483

RESUMO

The growth plate is a cartilaginous layer present from the gestation period until the end of puberty where it ossifies joining diaphysis and epiphysis. During this period several endocrine, autocrine, and paracrine processes within the growth plate are carried out by chondrocytes; therefore, a disruption in cellular functions may lead to pathologies affecting bone development. It is known that electric fields impact the growth plate; however, parameters such as stimulation time and electric field intensity are not well documented. Accordingly, this study presents a histomorphometrical framework to assess the effect of electric fields on chondroepiphysis explants. Bones were stimulated with 3.5 and 7 mV/cm, and for each electric field two exposure times were tested for 30 days (30 min and 1 h). Results evidenced that electric fields increased the hypertrophic zones compared with controls. In addition, a stimulation of 3.5 mV/cm applied for 1 h preserved the columnar cell density and its orientation. Moreover, a pre-hypertrophy differentiation in the center of the chondroepiphysis was observed when explants were stimulated during 1 h with both electric fields. These findings allow the understanding of the effect of electrical stimulation over growth plate organization and how the stimulation modifies chondrocytes morphophysiology.


Assuntos
Condrócitos/citologia , Estimulação Elétrica , Lâmina de Crescimento/crescimento & desenvolvimento , Animais , Proliferação de Células , Células Cultivadas , Condrócitos/patologia , Condrócitos/ultraestrutura , Estimulação Elétrica/instrumentação , Desenho de Equipamento , Fêmur/citologia , Fêmur/crescimento & desenvolvimento , Fêmur/patologia , Fêmur/ultraestrutura , Lâmina de Crescimento/citologia , Lâmina de Crescimento/patologia , Lâmina de Crescimento/ultraestrutura , Úmero/citologia , Úmero/crescimento & desenvolvimento , Úmero/patologia , Úmero/ultraestrutura , Hipertrofia , Osteogênese , Ratos , Ratos Wistar
6.
Science ; 362(6411)2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30309914

RESUMO

Slimak et al challenge the reliability of our oldest (>65,000 years) U-Th dates on carbonates associated with cave paintings in Spain. They cite a supposed lack of parietal art for the 25,000 years following this date, along with potential methodological issues relating to open-system behavior and corrections to detrital or source water 230Th. We show that their criticisms are unfounded.


Assuntos
Cavernas , Homem de Neandertal , Carbonatos , Reprodutibilidade dos Testes , Espanha
7.
Science ; 359(6378): 912-915, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29472483

RESUMO

The extent and nature of symbolic behavior among Neandertals are obscure. Although evidence for Neandertal body ornamentation has been proposed, all cave painting has been attributed to modern humans. Here we present dating results for three sites in Spain that show that cave art emerged in Iberia substantially earlier than previously thought. Uranium-thorium (U-Th) dates on carbonate crusts overlying paintings provide minimum ages for a red linear motif in La Pasiega (Cantabria), a hand stencil in Maltravieso (Extremadura), and red-painted speleothems in Ardales (Andalucía). Collectively, these results show that cave art in Iberia is older than 64.8 thousand years (ka). This cave art is the earliest dated so far and predates, by at least 20 ka, the arrival of modern humans in Europe, which implies Neandertal authorship.


Assuntos
Homem de Neandertal , Pinturas/história , Animais , Antropologia Cultural , Carbonatos/química , Cavernas , História Antiga , Humanos , Espanha , Tório/análise , Urânio/análise
8.
Biomech Model Mechanobiol ; 17(3): 853-875, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29322335

RESUMO

Long bone formation starts early during embryonic development through a process known as endochondral ossification. This is a highly regulated mechanism that involves several mechanical and biochemical factors. Because long bone development is an extremely complex process, it is unclear how biochemical regulation is affected when dynamic loads are applied, and also how the combination of mechanical and biochemical factors affect the shape acquired by the bone during early development. In this study, we develop a mechanobiological model combining: (1) a reaction-diffusion system to describe the biochemical process and (2) a poroelastic model to determine the stresses and fluid flow due to loading. We simulate endochondral ossification and the change in long bone shapes during embryonic stages. The mathematical model is based on a multiscale framework, which consisted in computing the evolution of the negative feedback loop between Ihh/PTHrP and the diffusion of VEGF molecule (on the order of days) and dynamic loading (on the order of seconds). We compare our morphological predictions with the femurs of embryonic mice. The results obtained from the model demonstrate that pattern formation of Ihh, PTHrP and VEGF predict the development of the main structures within long bones such as the primary ossification center, the bone collar, the growth fronts and the cartilaginous epiphysis. Additionally, our results suggest high load pressures and frequencies alter biochemical diffusion and cartilage formation. Our model incorporates the biochemical and mechanical stimuli and their interaction that influence endochondral ossification during embryonic growth. The mechanobiochemical framework allows us to probe the effects of molecular events and mechanical loading on development of bone.


Assuntos
Biofísica , Simulação por Computador , Modelos Biológicos , Osteogênese , Animais , Cartilagem/fisiologia , Fêmur/anatomia & histologia , Análise de Elementos Finitos , Lâmina de Crescimento/crescimento & desenvolvimento , Proteínas Hedgehog/metabolismo , Camundongos Endogâmicos BALB C , Morfogênese , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Reologia , Estresse Mecânico
9.
In Silico Biol ; 12(3-4): 83-93, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-26756921

RESUMO

Articular cartilage is characterized by low cell density of only one cell type, chondrocytes, and has limited self-healing properties. When articular cartilage is affected by traumatic injuries, a therapeutic strategy such as autologous chondrocyte implantation is usually proposed for its treatment. This approach requires in vitro chondrocyte expansion to yield high cell number for cell transplantation. To improve the efficiency of this procedure, it is necessary to assess cell dynamics such as migration, proliferation and cell death during culture. Computational models such as cellular automata can be used to simulate cell dynamics in order to enhance the result of cell culture procedures. This methodology has been implemented for several cell types; however, an experimental validation is required for each one. For this reason, in this research a cellular automata model, based on random-walk theory, was devised in order to predict articular chondrocyte behavior in monolayer culture during cell expansion. Results demonstrated that the cellular automata model corresponded to cell dynamics and computed-accurate quantitative results. Moreover, it was possible to observe that cell dynamics depend on weighted probabilities derived from experimental data and cell behavior varies according to the cell culture period. Thus, depending on whether cells were just seeded or proliferated exponentially, culture time probabilities differed in percentages in the CA model. Furthermore, in the experimental assessment a decreased chondrocyte proliferation was observed along with increased passage number. This approach is expected to having other uses as in enhancing articular cartilage therapies based on tissue engineering and regenerative medicine.


Assuntos
Cartilagem Articular , Morte Celular , Proliferação de Células , Condrócitos , Modelos Biológicos , Técnicas de Cultura de Células , Humanos , Engenharia Tecidual
10.
J Mol Graph Model ; 60: 169-79, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26059478

RESUMO

A thorough DFT and MM study of the conformational landscape, molecular and electronic structures of (-)-S-anabasine is reported aimed to reveal the mechanism controlling its conformational preference. Although the conformational flexibility and diversity of this system is quite extensive, only two structures are populated both in gas-phase and solution (CCl4 and DMSO). NBO-aided electronic structure analyses performed for the eight conformers representing minima in the potential energy surface of (-)-S-anabasine indicate that both steric and electrostatic factors are determinant in the conformational distribution of the sample in gas phase. Nonetheless, hyperconjugative effects are the key force tipping the balance in the conformational equilibrium between the two main rotamers. Increasing the polarity of the medium (using the IEF-PCM formalism) barely affect the conformational energy profile, although a slight increase in the theoretical population of those structures more affected by electrostatic interactions is predicted. The validity of the theoretical models and calculated conformers populations are endorsed by the accurate reproduction of the IR and VCD spectra (recorded in pure liquid and in CCl4 solution) of the sample (that have been firstly recorded and assigned in the present work) which are consistent with the occurrence of a 2:1 conformational ratio.


Assuntos
Anabasina/química , Dicroísmo Circular/métodos , Nicotiana/química , Teoria Quântica , Tetracloreto de Carbono , Dimetil Sulfóxido , Gases , Modelos Moleculares , Conformação Molecular , Reprodutibilidade dos Testes , Soluções , Solventes , Espectrofotometria Infravermelho , Estereoisomerismo , Vibração
11.
Mol Biochem Parasitol ; 201(1): 16-25, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26024834

RESUMO

Previously, we have studied the effect of the gold-compound auranofin (AF) on both thioredoxin-glutathione reductasa (TGR) activity and viability of Taenia crassiceps cysticerci. It was demonstrated that micromolar concentrations of AF were high enough to fully inhibit TGR and kill the parasites. In this work, the dynamics of changes in the glutathione pool of T. crassiceps cysticerci following the addition of AF, was analyzed. A dose-dependent decrease in the internal glutathione concentration, concomitant with an increase in ROS production was observed. These changes were simultaneous with the formation of glutathione-protein complexes and the export of glutathione disulfide (GSSG) to the culture medium. Incubation of cysticerci in the presence of both AF and N-acetyl cysteine (NAC) prevents all the above changes, maintaining cysticerci viability. By contrast, the presence of both AF and buthionine sulfoximine (BSO) resulted in a potentiation of the effects of the gold compound, jeopardizing cysticerci viability. These results suggest the lethal effect of AF on T. crassiceps cysticerci, observed at micromolar concentrations, can be explained as a consequence of major changes in the glutathione status, which results in a significant increase in the oxidative stress of the parasites.


Assuntos
Auranofina/toxicidade , Glutationa/análise , Oxidantes/toxicidade , Estresse Oxidativo , Taenia/química , Taenia/efeitos dos fármacos , Acetilcisteína/metabolismo , Animais , Antioxidantes/metabolismo , Butionina Sulfoximina/metabolismo , Cysticercus/química , Cysticercus/efeitos dos fármacos , Cysticercus/fisiologia , Espécies Reativas de Oxigênio/análise , Análise de Sobrevida , Taenia/fisiologia
12.
Comput Methods Programs Biomed ; 118(1): 59-68, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25453383

RESUMO

Mechanical stimuli play a significant role in the process of long bone development as evidenced by clinical observations and in vivo studies. Up to now approaches to understand stimuli characteristics have been limited to the first stages of epiphyseal development. Furthermore, growth plate mechanical behavior has not been widely studied. In order to better understand mechanical influences on bone growth, we used Carter and Wong biomechanical approximation to analyze growth plate mechanical behavior, and explore stress patterns for different morphological stages of the growth plate. To the best of our knowledge this work is the first attempt to study stress distribution on growth plate during different possible stages of bone development, from gestation to adolescence. Stress distribution analysis on the epiphysis and growth plate was performed using axisymmetric (3D) finite element analysis in a simplified generic epiphyseal geometry using a linear elastic model as the first approximation. We took into account different growth plate locations, morphologies and widths, as well as different epiphyseal developmental stages. We found stress distribution during bone development established osteogenic index patterns that seem to influence locally epiphyseal structures growth and coincide with growth plate histological arrangement.


Assuntos
Desenvolvimento Ósseo/fisiologia , Simulação por Computador , Lâmina de Crescimento/crescimento & desenvolvimento , Lâmina de Crescimento/fisiologia , Adolescente , Criança , Pré-Escolar , Epífises/embriologia , Epífises/crescimento & desenvolvimento , Epífises/fisiologia , Feminino , Análise de Elementos Finitos , Lâmina de Crescimento/embriologia , Humanos , Lactente , Recém-Nascido , Modelos Lineares , Masculino , Modelos Biológicos , Osteogênese/fisiologia , Gravidez , Estresse Mecânico
13.
Parasitol Int ; 64(2): 194-201, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25523293

RESUMO

Thioredoxin (Trx) is an oxidoreductase central to redox homeostasis in cells and is involved in the regulation of protein activity through thiol/disulfide exchanges. Based on these facts, our goal was to purify and characterize cytosolic thioredoxin from Taenia crassiceps cysticerci, as well as to study its behavior as a substrate of thioredoxin-glutathione reductase (TGR). The enzyme was purified >133-fold with a total yield of 9.7%. A molecular mass of 11.7kDa and a pI of 4.84 were measured. Native electrophoresis was used to identify the oxidized and reduced forms of the monomer as well as the presence of a homodimer. In addition to the catalytic site cysteines, cysticerci thioredoxin contains Cys28 and Cys65 residues conserved in previously sequenced cestode thioredoxins. The following kinetic parameters were obtained for the substrate of TGR: a Km of 3.1µM, a kcat of 10s(-1) and a catalytic efficiency of 3.2×10(6)M(-1)s(-1). The negative patch around the α3-helix of Trx is involved in the interaction with TGR and suggests variable specificity and catalytic efficiency of the reductase toward thioredoxins of different origins.


Assuntos
Regulação Enzimológica da Expressão Gênica/fisiologia , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , Taenia/metabolismo , Tiorredoxinas/metabolismo , Sequência de Aminoácidos , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Dados de Sequência Molecular , Complexos Multienzimáticos/genética , NADH NADPH Oxirredutases/genética , Conformação Proteica , Especificidade por Substrato , Taenia/enzimologia , Taenia/genética , Tiorredoxinas/genética
14.
Pediatr. aten. prim ; 16(61): e37-e46, ene.-mar. 2014.
Artigo em Espanhol | IBECS | ID: ibc-121763

RESUMO

Los niños con trastornos del espectro autista (TEA) coinciden en unos déficits que afectan la interacción social, la comunicación y la flexibilidad en razonamiento. Además, en algunos existen unos déficits motores, que afectarán a lo largo de la vida, y que son susceptibles de tratamiento desde la fisioterapia. Por lo tanto, la figura del fisioterapeuta es necesaria para una intervención precoz del niño, aprovechando la plasticidad cerebral, para incidir positivamente en el desarrollo, así como en la calidad de vida, y conseguir una correcta integración social. Se sabe que el tratamiento en el agua tiene una gran eficacia y un gran papel en el desarrollo del niño con TEA, donde el fisioterapeuta, aparte de trabajar los déficits motores, incidirá indirectamente en aspectos ligados a los déficits comunes del TEA (vínculo y comunicación). La cointervención entre psicomotricista y fisioterapeuta, efectuada al mismo tiempo, aparte de incidir en el desarrollo del niño, ayudará a tratarlo desde dos perspectivas distintas. Así, se tratan, por una parte, aspectos ligados a temas emocionales y conductuales y, por otra parte, aspectos físicos. Ambas coinciden en el tratamiento a través del juego. Se abre una nueva línea dentro de la fisioterapia pediátrica, en este caso dentro del ámbito paidopsiquiátrico. Por lo tanto, se trata de una oportunidad emergente de adquirir nuevos tratamientos de fisioterapia integrando el fisioterapeuta en el equipo multidisciplinar del TEA. Por ello, el fisioterapeuta participará directamente en un proyecto de atención integral del niño y adoptará el rol de agente promotor de la salud (AU)


Children with Autism Spectrum Disorder (ASD) coincide on deficits affecting social interaction, communication and flexibility in thinking. Furthermore, some exhibit lifetime motor deficits that can benefit by means of physiotherapy. Therefore, the figure of the physiotherapist is necessary for early intervention in the child, taking advantage of their brain plasticity to impact positively on their development and quality of life, and to obtain a proper social integration. It is well known that water treatment is highly effective and it has an important role in the development of children with ASD, where the physiotherapist, besides working motor deficits, indirectly will positively influence aspects related to common deficits of the ASD (communication and attachment). A co-intervention with a psychomotor-therapist and physiotherapist performed at the same time, besides influencing child development, will help manage the child from two different perspectives: aspects associated with emotional and behavioural problems, besides physical aspects. Both take place through play or game. This fact opens a new line in pediatric physiotherapy, in this case, within child psychiatry. It is an emerging opportunity to contribute with new physiotherapy treatments integrating the physiotherapist in the multidisciplinary ASD team. This way the physiotherapist is directly involved in an integral child care project, and assuming the role of a health-promoting agent


Assuntos
Humanos , Masculino , Feminino , Criança , Transtorno Autístico/fisiopatologia , Transtorno Autístico/terapia , Modalidades de Fisioterapia , Hidroterapia/métodos , Hidroterapia , Diagnóstico Precoce , Serviço Hospitalar de Fisioterapia/organização & administração , Transtornos Psicomotores/complicações , Transtornos Psicomotores/terapia , Qualidade de Vida , 28599
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 118: 828-34, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24157334

RESUMO

On the way towards the development of a synthetic route aimed at obtaining new methylsilanediol derivatives with an aminocarbonyl group in ß to silicon (which may have a potential biological interest), we have synthesized, isolated and purified five diphenylic possible precursors, namely chloromethyl(methyl)diphenylsilane, 2-{[methyl(diphenyl)silyl]methyl}-1H-isoindole-1,3(2H)-dione, N-[(methyl(diphenyl) silanyl)-methyl]-benzamide, N-[(methyl(diphenyl)silyl)-methyl]-acetamide and N-[(methyl(diphenyl)silyl)-methyl]-formamide. The conformational landscape of the five species in this study are explored by means of DFT calculations at the B3LYP/6-311++G(∗∗) level. The theoretical molecular structures predicted are confirmed by the reproduction of their respective IR and Raman spectral profiles, that are completely assigned. Some evidence in the vibrational spectra points to the occurrence of conformational mixtures in the samples. Further, single-crystal X-ray diffraction has allowed the elucidation of the crystalline structure of 2-{[methyl(diphenyl)silyl]methyl}-1H-isoindole-1,3(2H)-dione.


Assuntos
Silanos/química , Cristalografia por Raios X , Metilação , Modelos Moleculares , Conformação Molecular , Teoria Quântica , Silanos/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
16.
Chemphyschem ; 14(14): 3355-60, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-23853070

RESUMO

1H-indazoles are good candidates for studying the phenomena of molecular association and spontaneous resolution of chiral compounds. Thus, because the 1H-indazoles can crystallize as dimers, trimers, or catemers, depending on their structure and the phase that they are in, the difficulty in the experimental analysis of the structure of the family of 1H-indazoles becomes clear. This difficulty leads us to contemplate several questions: How can we determine the presence of different structures of a given molecular species if they change according to the phase? Could these different structures be present in the same phase simultaneously? How can they be determined? To shed light on these questions, we outline a very complete strategy by using various vibrational spectroscopic techniques that are sensitive (VCD) and insensitive (IR, FIR, and Raman) towards the chirality, together with quantum chemical calculations.

17.
Talanta ; 108: 53-8, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23601869

RESUMO

In most laser-based analytical methods, the reproducibility of quantitative measurements strongly depends on maintaining uniform and stable experimental conditions. For LIBS analysis this means that for accurate estimation of elemental concentration, using the calibration curves obtained from reference samples, the plasma parameters have to be kept as constant as possible. In addition, calcified tissues such as bone are normally less "tough" in their texture than many samples, especially metals. Thus, the ablation process could change the sample morphological features rapidly, and result in poor reproducibility statistics. In the present work, three artificial reference sample sets have been fabricated. These samples represent three different calcium based matrices, CaCO3 matrix, bone ash matrix and Ca hydroxyapatite matrix. A comparative study of UV (266 nm) and IR (1064 nm) LIBS for these three sets of samples has been performed under similar experimental conditions for the two systems (laser energy, spot size, repetition rate, irradiance, etc.) to examine the wavelength effect. The analytical results demonstrated that UV-LIBS has improved reproducibility, precision, stable plasma conditions, better linear fitting, and the reduction of matrix effects. Bone ash could be used as a suitable standard reference material for calcified tissue calibration using LIBS with a 266 nm excitation wavelength.


Assuntos
Carbonato de Cálcio/química , Cálcio/análise , Durapatita/química , Minerais/química , Análise Espectral/métodos , Lasers
18.
Neurocirugia (Astur) ; 21(4): 302-5, 2010 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-20725698

RESUMO

OBJECTIVE: The authors' objective is to report the initial appreciations on the use of the intraoperative near-infrared indocyanine green videoangiography during aneurysm surgery in our center. METHOD: 10 surgical procedures have been made in 9 patients, 5 males and 4 females between 27 and 61 years old with an average of age of 49 years during a time of 10 months between March, 2008 and January, 2009. 10 surgical procedures were performed and 11 aneurysms were clipped. Intravenous indocyanine green and surgical microscope Leica OH4 with module of vascular fluorescence intraoperating Leica FL800, with camera infrared Sony (Heerbrugg-Switzerland) were used. The information offered by this technique during the intervention is compared with the images of the postoperative angiography performed during the first 24 hours. The partial or complete occlusion and the respect to the near vessels were evaluated. RESULTS: The findings of the intraoperative videoangiography were the complete occlusion and absence of complications in all the cases. These results corresponded completely with the postoperative results of the angiography postoperative, except in a case where the angiography demonstrated vasoespasmo moderate without clinical repercussion that during the videoangiografía intraoperatoria was not perceived. Clinically no patient presented neurological added deficits. CONCLUSIONS: The intraoperative videoangiography is a tool of easy application that offers valuable information as for the complete occlusion of the aneurysm and the permeability of the adjacent vessels.


Assuntos
Angiografia Cerebral/métodos , Corantes , Verde de Indocianina , Aneurisma Intracraniano , Monitorização Intraoperatória/métodos , Gravação em Vídeo/métodos , Adulto , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico , Aneurisma Intracraniano/cirurgia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
19.
Neurocir. - Soc. Luso-Esp. Neurocir ; 21(4): 302-305, jul.-ago. 2010. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-95477

RESUMO

Objetivo. El objetivo de los autores es reportar nuestra experiencia inicial sobre la utilización de la videoangiografía intraoperatoria con verde de indocianina durante la cirugía de aneurismas cerebrales en nuestrocentro. Material y métodos. Se han realizado 10 procedimientos quirúrgicos en 9 pacientes, 5 varones y 4 mujeres entre 27 y 61 años con una media de edad de 49 años durante un tiempo de 10 meses entre marzo de 2008 y enero de2009. Se realizaron 10 intervenciones y se cliparon 11aneurismas, de los cuales 5 fueron diagnosticados tras su ruptura y 6 no. Se utilizaron verde de indocianina intravenosa y microscopio quirúrgico Leica OH4 con módulo de fluorescencia vascular intraoperatoria Leica FL800, con cámara infrarroja Sony (Heerbrugg-Suiza).Se recoge la información ofrecida por esta técnica durante la intervención y se compara con las imágenes de la arteriografía postoperatoria a las 24 horas. Se valoraron la oclusión total o parcial de la lesión aneurismática así como la preservación o no de la vascularización adyacente. Resultados. Los hallazgos de la videoangiografía intraoperatoria sobre las lesiones aneurismáticas fueron de oclusión completa en todos los casos y permeabilidad de los vasos vecinos. Estos resultados se corresponden completamente con los de la arteriografía postoperatoria,excepto en un caso donde la arteriografía evidenció vasoespasmo moderado-grave sin repercusión clínica que durante la videoangiografía intraoperatoriano fue percibido. Clínicamente ningún paciente presentó déficits neurológicos añadidos.Conclusiones. La videoangiografía intraoperatoria es una herramienta de fácil aplicación que ofrece información valiosa en cuanto a la oclusión completa del saco aneurismático y la permeabilidad de los vasos adyacentesa éste (AU)


Objective. The authors’ objective is to report the initialappreciations on the use of the intraoperative near infraredindocyanine green videoangiography during aneurysm surgery in our center.Method. 10 surgical procedures have been made in 9 patients, 5 males and 4 females between 27 and 61 years old with an average of age of 49 years during a time of 10 months between March, 2008 and January, 2009. 10 surgical procedures were performed and 11 aneurysms were clipped. Intravenous indocyanine green and surgical microscope LeicaOH4 with module of vascular fluorescence intraoperating Leica FL800, with camera infrared Sony (Heerbrugg-Switzerland)were used. The information offered by this techniqueduring the intervention is compared with the images of the postoperative angiography performed during the first 24hours. The partial or complete occlusion and the respect to the near vessels were evaluated. Results. The findings of the intraoperative videoangiography were the complete occlusion and absence of complications in all the cases. These results corresponded completely with the postoperative results of the angiography postoperative, except in a case where the angiography demonstrated vasoespasmo moderate without clinical repercussion that during the videoangiografía intraoperatoria was not perceived. Clinically no patient presented neurological added deficits.Conclusions. The intraoperative videoangiographyis a tool of easy application that offers valuable informationas for the complete occlusion of the aneurysmand the permeability of the adjacent vessels (AU)


Assuntos
Humanos , Cirurgia Vídeoassistida/métodos , Angiografia Cerebral/métodos , Aneurisma Intracraniano/cirurgia , Verde de Indocianina , Permeabilidade Capilar
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