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1.
Mol Ecol ; 32(9): 2186-2205, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36798996

RESUMO

Understanding the factors that govern variation in genetic structure across species is key to the study of speciation and population genetics. Genetic structure has been linked to several aspects of life history, such as foraging strategy, habitat association, migration distance, and dispersal ability, all of which might influence dispersal and gene flow. Comparative studies of population genetic data from species with differing life histories provide opportunities to tease apart the role of dispersal in shaping gene flow and population genetic structure. Here, we examine population genetic data from sets of bird species specialized on a series of Amazonian habitat types hypothesized to filter for species with dramatically different dispersal abilities: stable upland forest, dynamic floodplain forest, and highly dynamic riverine islands. Using genome-wide markers, we show that habitat type has a significant effect on population genetic structure, with species in upland forest, floodplain forest, and riverine islands exhibiting progressively lower levels of structure. Although morphological traits used as proxies for individual-level dispersal ability did not explain this pattern, population genetic measures of gene flow are elevated in species from more dynamic riverine habitats. Our results suggest that the habitat in which a species occurs drives the degree of population genetic structuring via its impact on long-term fluctuations in levels of gene flow, with species in highly dynamic habitats having particularly elevated gene flow. These differences in genetic variation across taxa specialized in distinct habitats may lead to disparate responses to environmental change or habitat-specific diversification dynamics over evolutionary time scales.


A compreensão dos fatores que governam a variação da estrutura genética entre as espécies é fundamental para o estudo da especiação e da genética das populações. A estrutura genética tem sido ligada a vários aspectos da história da vida, tais como estratégia de forrageio, associação ao habitat, distância de migração e capacidade de dispersão, os quais poderiam influenciar a dispersão e o fluxo gênico. Estudos comparativos usando espécies que diferem nas suas histórias de vida oferecem uma oportunidade para desvendar o papel da dispersão no estabelecimento do fluxo gênico e da estrutura genética da população. Aqui examinamos dados genéticos populacionais de diversas espécies de aves com diferentes capacidades de dispersão especializadas em três habitats amazônicos, incluindo florestas de terra-firme, florestas de várzea e ilhas fluviais, cujos ambientes ripários são altamente dinâmicos. Utilizando dados genômicos que incluem milhares de loci, mostramos que o tipo de habitat tem um efeito significativo na estruturação genética das populações; espécies de florestas de terra-firme, florestas de várzea e ilhas fluviais exibem níveis de estruturação progressivamente menores. Embora os traços morfológicos frequentemente usados como indicadores da capacidade de dispersão a nível individual não expliquem este padrão, as medidas genéticas populacionais de fluxo gênico são altas em espécies associadas a habitats ribeirinhos mais dinâmicos. Nossos resultados sugerem que o habitat no qual uma espécie é encontrada determina o grau de estruturação genética da população através de seu impacto nas flutuações de longo prazo do fluxo gênico, com espécies em habitats altamente dinâmicos tendo um fluxo gênico particularmente alto. As diferenças na variação genética dos táxons especializados em diferentes habitats podem resultar em respostas díspares às mesmas mudanças ambientais, ou dinâmicas de diversificação específicas a um determinado habitat ao longo de escalas de tempo evolutivas.


Comprender los factores que rigen la variación de la estructura genética entre especies es clave para el estudio de la especiación y la genética de poblaciones. La estructura genética se ha relacionado con varios aspectos de la historia vital, como la estrategia de búsqueda de alimento, la asociación de hábitats, la distancia de migración y la capacidad de dispersión, factores todos ellos que podrían influir en la dispersión y el flujo genético. Los estudios comparativos de datos genéticos poblacionales de especies con historias vitales diferentes ofrecen la oportunidad de desentrañar el papel de la dispersión en la conformación del flujo genético y la estructura genética poblacional. En este trabajo examinamos los datos genéticos de poblaciones de especies de aves especializadas en una serie de hábitats amazónicos que, según la hipótesis, filtran especies con capacidades de dispersión radicalmente diferentes: bosques estables de tierras altas, bosques dinámicos de llanuras aluviales e islas fluviales altamente dinámicas. Utilizando marcadores genómicos, demostramos que el tipo de hábitat tiene un efecto significativo en la estructura genética de la población, y que las especies de los bosques de tierras altas, los bosques inundables y las islas fluviales presentan niveles de estructura progresivamente más bajos. Aunque los rasgos morfológicos utilizados como indicadores de la capacidad de dispersión individual no explican este patrón, las medidas genéticas poblacionales del flujo genético son más elevadas en las especies de hábitats fluviales más dinámicos. Nuestros resultados sugieren que el hábitat en el que se encuentra una especie determina el grado de estructuración genética de la población a través de su impacto en las fluctuaciones a largo plazo de los niveles de flujo genético, siendo las especies de hábitats muy dinámicos las que presentan un flujo genético particularmente elevado. Estas diferencias en la variación genética entre taxones especializados en hábitats distintos pueden dar lugar a respuestas dispares al cambio ambiental o a dinámicas de diversificación específicas del hbitat a lo largo de escalas temporales evolutivas.


Assuntos
Ecossistema , Fluxo Gênico , Animais , Florestas , Aves/genética , Genética Populacional , Variação Genética
2.
An Acad Bras Cienc ; 95(2): e20201599, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37255126

RESUMO

We collected data during three consecutive breeding seasons (2015-2018) to assess the effects of Taphropiestes plaumanni (Coleoptera: Cavognathidae) on its bird hosts in a native forest of central eastern Argentina. We monitored bird nests for T. plaumanni in 207 nests of Masked Gnatcatcher (Polioptila dumicola, Polioptilidae), 302 nests of Vermilion Flycatcher (Pyrocephalus rubinus, Tyrannidae), 55 nests of Blue-and-yellow Tanager (Pipraeidea bonariensis, Thraupidae), 99 nests of Small-billed Elaenia (Elaenia parvirostris, Tyrannidae), 23 nests of Yellow-browed Tyrant (Satrapa icterophrys, Tyrannidae), and other passerine species nesting in the same forest patches. We found 13 nests in which nestlings showed evidences of parasitism of which four species are new hosts for this parasite (Vermilion Flycatcher, Masked Gnatcatcher, Red-crested Cardinal Paroaria coronata, Thraupidae, and Fork-tailed Flycatcher Tyrannus savana). Skin lesions caused by T. plaumanni larvae consisted in lacerations and crusts on the belly and chest areas. In one parasitized nest of Vermilion Flycatcher and one parasitized nest of Masked Gnatcatcher we observed the death of nestlings after being parasitized. This study adds new species to the list of hosts for this parasite, reports nestling skin lesions in nests with T. plaumanni parasitism, and reports for the first time the death of parasitized nestlings.


Assuntos
Besouros , Parasitos , Passeriformes , Animais , Comportamento de Nidação , Larva , Argentina
3.
J Comput Chem ; 43(22): 1484-1494, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35731622

RESUMO

In the present study, the differential scattering cross-sections, depolarization ratios and Raman shifts of small molecular systems are obtained from configuration iteration wave functions of vibrational self-consistent field (VSCF) states. The transition polarizabilities were modeled using the Placzek approximation, neglecting those contributions not arising from the electric dipole mechanism. This theoretical approach is considered a good approximation for samples that absorb in the UV range if the excitation radiation falls in the visible region, as is the case of the molecules selected for the present study, namely: water, methane, and acetylene. Potential energy and electronic polarizability surfaces are calculated by the CCSD(T) and CC3 methods with aug-cc-p(C)V(T,Q,5)Z basis sets. The vibrational Hamiltonian includes the vibrational angular momentum contribution of the Watson kinetic energy operator. As expected, due to the variational nature of the VSCF and vibrational configuration interaction (VCI) methods, the Raman transition wavenumbers are substantially improved over the harmonic predictions. Surprisingly, the scattering cross-sections obtained using the harmonic approximation or the VSCF method better agrees with the experimental values than those cross-sections predicted using VCI wave functions. The more significant deviations of the VCI results from the experimental reference may be related to the significant uncertainties of the measured cross-sections. Still, it may also indicate that the VCI Raman transition moments may require a more accurate description of the electronic polarizability surface. Finally, the depolarization ratios calculated for H2 O and C2 D2 using harmonic and VCI wave functions have similar accuracy, whereas, for C2 H2 and C2 HD, the VCI results are more accurate.


Assuntos
Teoria Quântica , Análise Espectral Raman , Vibração , Água
4.
J Phys Chem A ; 125(15): 3219-3229, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33847496

RESUMO

We present a complete theoretical protocol to partition infrared intensities into terms owing to individual atoms by two different but related approaches: the atomic contributions (ACs) show how the entire molecular vibrational motion affects the electronic structure of a single atom and the total infrared intensity. On the other hand, the dynamic contributions (DCs) show how the displacement of a single atom alters the electronic structure of the entire molecule and the total intensity. The two analyses are complementary ways of partitioning the same total intensity and conserve most of the features of the total intensity itself. Combined, they are called the AC/DC analysis. These can be further partitioned following the CCTDP (or CCT) models according to the population analysis chosen by the researcher. The main conceptual features of the equations are highlighted, and representative numerical results are shown to support the interpretation of the equations. The results are invariant to rotation and translation and can readily be extended to molecules of any size, shape, or symmetry. Although the AC/DC analysis requires the choice of a charge model, all charge models that correctly reproduce the total molecular dipole moment can be used. A fully automated protocol managed by the Placzek program is made available, free of charge and with input examples.

5.
An Acad Bras Cienc ; 93(suppl 4): e20210520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34852066

RESUMO

Fluctuation asymmetries (FA) are random on the bilateral symmetry plan of paired morphological characters, and other types of symmetry, such as: for instance, translational or rotational symmetry, in response to environmental, and genetic stress. The relationship of FA with gonadossomatic (GSI), hepatosomatic (HSI), and fullness (RI) indexes and condition factor (K) for juveniles (n=8), adults (n=32), males (n=9), and females (n=26) of Corocoro grunt Orthopristis ruber were evaluated in this paper. The composite fluctuating asymmetry (CFA) was used to calculate the combined effects of FA over these four organosomatic indexes of 66 Corocoro grunt caught during 2011 in Guanabara Bay, Brazil, one of the most eutrophic coastal bays in the world. Redundancy Analysis (RDA) confirmed a significant relationship between CFA and the physiological descriptors (HSI, RI, K), but without clear differences among juveniles, adults, and sexes. Our results support the potential of CFA to be used as a proxy of environmental effects over reef-associated fish species in a tropical bay, but the relationship between CFA and physiological descriptors is complex, and further studies, such as experimental trials, are needed.


Assuntos
Baías , Peixes , Animais , Brasil , Feminino , Masculino
6.
An Acad Bras Cienc ; 93(4): e20191221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495199

RESUMO

The invasion record for the estuarine bivalve Mytilopsis leucophaeata in Brazil is in Rio de Janeiro city, including the Rodrigo de Freitas Lagoon, where high densities of this invader were registered. This work aimed to (1) assess the composition and structure of the benthic macrofauna associated with this invader in Rodrigo de Freitas Lagoon, (2) analyze the spatiotemporal variation of richness, density and diversity of the associated benthic community, and (3) correlate changes on the density of the associated benthic species with some water quality variables and the density of M. leucophaeata. Clusters of M. leucophaeata were collected monthly (two years) in four sites. Nine taxa associated with M. leucophaeata were found; Heleobia sp. (Gastropoda) and Melita mangrovi (Amphipoda) showed the highest densities. The structure of the benthic macrofauna slightly differed among sampling sites, but not between dry and wet seasons. The water quality parameters, specific patterns of each taxon and high densities of M. leucophaeata contribute to variations in density of the associated species. Oscillations in the densities of M. leucophaeata and the native bivalve Brachidontes darwinianus suggest some agonistic relationship between them, such as a competition for space.


Assuntos
Anfípodes , Bivalves , Animais , Brasil , Estações do Ano , Qualidade da Água
7.
Mol Ecol ; 29(12): 2129-2132, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32392379

RESUMO

One of the main goals of evolutionary biology is to understand the processes behind current patterns of biodiversity. Shared geographic distributions among unrelated species may result from a common history, providing a unique opportunity to assess the evolution of the landscape and the origins of biodiversity. Until recently, vicariance prevailed as the main evolutionary model to be tested, and the riverine barrier hypothesis the null model for taxa with river-bounded distributions. In recent years, however, multispecies comparative approaches have unveiled idiosyncratic scenarios among codistributed species, suggesting that rivers may or may not play a role in the speciation process. In a From the Cover article in this issue of Molecular Ecology, Kopuchian et al. (2020) explore predictions of the riverine barrier hypothesis in a major subtropical river system, evaluating the degree of mitochondrial and nuclear genomic differentiation in seven bird species with allegedly morphological differentiation across the Paraná-Paraguay river system. The authors show that in only one case, the genetic differentiation was concordant with the river. Interestingly, pairs presented disparate divergence times and/or distinct demographic histories. In most cases, putative contact zones broadly coincided with the transition of different ecoregions, such as the Espinal/Chaco ecological ecotone. These findings argue against the role of the Paraná-Paraguay river system as a major biogeographic barrier and highlight the need to explore the role of ecology in species diversification. Here, we feature different perspectives for studying the processes governing species divergence and suggest a basic protocol to advance the study of riverine barriers.


Assuntos
Especiação Genética , Rios , Animais , Biodiversidade , Aves , Filogenia
8.
Mol Ecol ; 29(22): 4457-4472, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32974981

RESUMO

South American dry forests have a complex and poorly understood biogeographic history. Based on the fragmented distribution of many Neotropical dry forest species, it has been suggested that this biome was more widely distributed and contiguous under drier climate conditions in the Pleistocene. To test this scenario, known as the Pleistocene Arc Hypothesis, we studied the phylogeography of the Rufous-fronted Thornbird (Phacellodomus rufifrons), a widespread dry forest bird with a disjunct distribution closely matching that of the biome itself. We sequenced mtDNA and used ddRADseq to sample 7,167 genome-wide single-nucleotide polymorphisms from 74 P. rufifrons individuals across its range. We found low genetic differentiation over two prominent geographic breaks - particularly across a 1,000 km gap between populations in Bolivia and Northern Peru. Using demographic analyses of the joint site frequency spectrum, we found evidence of recent divergence without subsequent gene flow across those breaks. By contrast, parapatric morphologically distinct populations in northeastern Brazil show high genetic divergence with evidence of recent gene flow. These results, in combination with our paleoclimate species distribution modelling, support the idea that currently disjunct patches of dry forest were more connected in the recent past, probably during the Middle and Late Pleistocene. This notion fits the major predictions of the Pleistocene Arc Hypothesis and illustrates the importance of comprehensive genomic and geographic sampling for examining biogeographic and evolutionary questions in complex ecosystems like Neotropical dry forests.


Assuntos
Aves , Ecossistema , Polimorfismo de Nucleotídeo Único , Animais , Aves/genética , Bolívia , Brasil , Florestas , Variação Genética , Peru , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único/genética
9.
Nanotechnology ; 31(35): 355706, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32434178

RESUMO

Nanoconfinement is one of the most intriguing nanoscale effects and affects several physical and chemical properties of molecules and materials, including viscosity, reaction kinetics, and glass transition temperature. In this work, liquid nuclear magnetic resonance (NMR) was used to analyze the behavior of 2,4-pentadienone in ordered mesoporous materials with a pore diameter of between 3 and 10 nm. The liquid NMR results showed meaningful changes in the hydrogen chemical shift and the keto-enol chemical equilibrium, which were associated with the pore diameter, allowing the authors to observe the effects of nanoconfinement. An interesting phenomenon was observed where the chemical equilibria of 2,4-pentadienone confined in a mesoporous material with a pore diameter of 3.5 nm was similar to that obtained with free (bulk) 2,4-pentadienone in larger pore materials. Another interesting result was observed for the enthalpy and entropy of the tautomeric equilibria of 2,4-pentadienone confined in mesoporous materials with a 5.5 nm pore diameter being -7.9 kJ mol-1 and -15.9 J mol-1.K. These values are similar to those obtained by dimethyl sulfoxide. This phenomenon indicates the possible use of ordered mesoporous materials as a reaction substitute in organic solvents. It was further observed that while the values of enthalpy (ΔH) and entropy (ΔS) had been modified by confinement, the Gibbs free energy (ΔG) value remained closer to that observed in free (bulk) 2,4-pentadienone. It is expected that this study will help in understanding the effects of nanoconfinement and provide a simple method to employ NMR techniques to analyze these phenomena.

10.
An Acad Bras Cienc ; 92(2): e20181096, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520216

RESUMO

The present study describes the community diversity and gives a seasonal distribution of an intertidal macroalgal assemblage at Prainha Beach, Arraial do Cabo City in Rio de Janeiro state, Brazil. Sampling was performed during four seasons of a 1-year period. Organisms were sampled and photographed using photoquadrats to quantify relative coverage. Ninety-six taxa of macroalgae were registered, including 23 chlorophytes, 19 ochrophytes, and 54 rhodophytes, while three barnacles, seven mollusks, one isopod, and one polychaete were recorded among the zoobenthos. In the upper intertidal zone, the coverage was frequently dominated by invertebrates. Macroalgae always dominated the middle and lower zones, covering almost 100 % in both zones. The highest values of species diversity (H'), richness (S), and turnover rates were found during the transition from spring to summer, which coincided with the upwelling period. A comparison with the 1980's flora revealed that the major changes in the macroalgal assemblage were among species belonging to the same genera, unless new additions were provided. The combination of photoquadrats and minimally destructive sampling allowed a detailed description of the composition and structural characteristics of the intertidal zone, a methodology that should be applied to study protected marine areas.


Assuntos
Organismos Aquáticos/classificação , Biodiversidade , Animais , Biomassa , Brasil , Estações do Ano
11.
Saudi Pharm J ; 27(8): 1096-1106, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31885469

RESUMO

Progesterone (PGT) is a natural hormone that stimulates and regulates various important functions, such as the preparation of the female body for conception and pregnancy. Due to its low water solubility, it is administered in a micronized form and/or in vehicles with specific solvents requirements. In order to improve the drug solubility, inclusion complexes of PGT and ß-cyclodextrins were obtained by the freeze-drying method. Two ß-cyclodextrins (native and methylated) in two solvents (water and water:ethanol) and different molar ratio of the reagents were the variables tested for the selection of the best condition for the preparation of the complexes. The PGT/randomly methylated-ß-cyclodextrin complexes were incorporated into chitosan thermosensitive hydrogels, as an alternative formulation for the vaginal administration of PGT. Neither the micro and macroscopic characteristics of the gels nor the transition time from solution to gel were modified after the complexes incorporation. In addition, chitosan gels with complexes resisted better the degradation in simulated vaginal fluid in comparison to commercial gel (Crinone®). The chitosan gel with inclusion complexes and Crinone® were tested in vitro in a diffusion assay to evaluate the delivery of the hormone and its diffusion through porcine epithelial mucosa obtained from vaginal tissue. Chitosan gel presented sustained diffusion similar to the exhibited by commercial gel. The use of chitosan gels with inclusion complexes based on cyclodextrins would be a viable alternative for vaginal administration of PGT.

12.
Ecology ; 99(2): 497, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29266462

RESUMO

South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on-line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeographic sub-regions. Considering the three main quantitative methods (mist net, point count, and line transect), we compiled abundance data for 745 species in 576 communities. In the data set, the most frequent species were Basileuterus culicivorus, Cyclaris gujanensis, and Conophaga lineata. There were 71 singletons, such as Lipaugus conditus and Calyptura cristata. We suggest that this small number of records reinforces the critical situation of these taxa in the Atlantic Forest. The information provided in this data set can be used for macroecological studies and to foster conservation strategies in this biodiversity hotspot. No copyright restrictions are associated with the data set. Please cite this Data Paper if data are used in publications and teaching events.

13.
Phys Chem Chem Phys ; 18(26): 17575-85, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27306140

RESUMO

The experimental infrared fundamental intensities of gas phase carbonyl compounds obtained by the integration of spectral bands in the Pacific Northwest National Laboratory (PNNL) spectral database are in good agreement with the intensities reported by other laboratories having a root mean square error of 27 km mol(-1) or about 13% of the average intensity value. The Quantum Theory of Atoms in Molecules/Charge-Charge Transfer-Counterpolarization (QTAIM/CCTCP) model indicates that the large intensity variation from 61.7 to 415.4 km mol(-1) is largely due to static atomic charge contributions, whereas charge transfer and counterpolarization effects essentially cancel one another leaving only a small net effect. The Characteristic Substituent Shift Model estimates the atomic charge contributions to the carbonyl stretching intensities within 30 km mol(-1) or 10% of the average contribution. However, owing to the size of the 2 × C × CTCP interaction contribution, the total intensities cannot be estimated with this degree of accuracy. The dynamic intensity contributions of the carbon and oxygen atoms account for almost all of the total stretching intensities. These contributions vary over large ranges with the dynamic contributions of carbon being about twice the size of the oxygen ones for a large majority of carbonyls. Although the carbon monoxide molecule has an almost null dipole moment contrary to the very polar bond of the characteristic carbonyl group, its QTAIM/CCTCP model is very similar to those found for the carbonyl compounds.

14.
Funct Integr Genomics ; 15(6): 685-96, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26013145

RESUMO

Asian soybean rust (ASR), caused by the obligate biotrophic fungus Phakopsora pachyrhizi, is one of most important diseases in the soybean (Glycine max (L.) Merr.) agribusiness. The identification and characterization of genes related to plant defense responses to fungal infection are essential to develop ASR-resistant plants. In this work, we describe four soybean genes, GmbZIP62, GmbZIP105, GmbZIPE1, and GmbZIPE2, which encode transcription factors containing a basic leucine zipper (bZIP) domain from two divergent classes, and that are responsive to P. pachyrhizi infection. Molecular phylogenetic analyses demonstrated that these genes encode proteins similar to bZIP factors responsive to pathogens. Yeast transactivation assays showed that only GmbZIP62 has strong transactivation activity in yeast. In addition, three of the bZIP transcription factors analyzed were also differentially expressed by plant defense hormones, and all were differentially expressed by fungal attack, indicating that these proteins might participate in response to ASR infection. The results suggested that these bZIP proteins are part of the plant defense response to P. pachyrhizi infection, by regulating the gene expression related to ASR infection responses. These bZIP genes are potential targets to obtain new soybean genotypes resistant to ASR.


Assuntos
Regulação da Expressão Gênica de Plantas , Glycine max/microbiologia , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Phakopsora pachyrhizi/patogenicidade , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Glycine max/genética , Glycine max/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Dedos de Zinco
15.
Scand J Rheumatol ; 44(1): 36-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25268749

RESUMO

OBJECTIVES: To determine the clinical and laboratory differences between cryoglobulinaemic and hypergammaglobulinaemic purpura in primary Sjögren's syndrome (pSS), in a large Italian multicentre cohort. METHOD: Patients were selected according to the following criteria: fulfilling the American-European classification criteria for pSS, serum cryoglobulin and gammaglobulin levels evaluated, and lack of hepatitis C virus (HCV) infection. Multinomial analyses were performed by distinguishing three groups of pSS: (i) purpura associated with cryoglobulinaemic vasculitis (CV), (ii) purpura associated with hypergammaglobulinaemic vasculitis (HGV), and (iii) pSS patients without purpura (pSS controls). Patients with purpura but without cryoglobulins or hypergammaglobulinaemia were excluded. RESULTS: A total of 652 patients were enrolled in this study. Group 1/CV comprised 23/652 patients (3.53%), group 2/HGV 40/652 patients (6.13%), and group 3/pSS controls 589/652 (90.34%). The three groups were found to be significantly different from each other (post-estimation test: group 1/CV vs. group 3/pSS controls: p < 0.0001; group 1/CV vs. group 2/HGV: p = 0.0001; group 2/HGV vs. group 3/pSS controls: p = 0.0003), thus confirming the different phenotypes of purpura in pSS.Multivariate analyses revealed that peripheral neuropathy (p < 0.001), low C4 (p < 0.001), leucopaenia (p = 0.01), serum monoclonal component (p = 0.02), and the presence of anti-SSB/La antibodies (p = 0.02) characterized CV whereas rheumatoid factor (p = 0.001), leucopaenia (p = 0.01), serum monoclonal component (p = 0.01), and anti-SSA/Ro antibodies (p = 0.049) were significantly associated with HGV. Lymphoma was associated only with CV. CONCLUSIONS: HGV is a cutaneous vasculitis, related to a benign B-cell proliferation, whereas CV is a systemic immune complex-mediated vasculitis with complement activation and a higher risk of lymphoma, thus confirming CV but not HGV as a prelymphomatous condition in pSS.


Assuntos
Crioglobulinemia/imunologia , Púrpura Hiperglobulinêmica/imunologia , Síndrome de Sjogren/imunologia , Adulto , Complexo Antígeno-Anticorpo/imunologia , Linfócitos B/imunologia , Estudos Transversais , Crioglobulinemia/sangue , Feminino , Humanos , Itália , Linfoma/sangue , Linfoma/imunologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Lesões Pré-Cancerosas/sangue , Lesões Pré-Cancerosas/imunologia , Prognóstico , Púrpura Hiperglobulinêmica/sangue , Estudos Retrospectivos , Síndrome de Sjogren/sangue , Vasculite/sangue , Vasculite/imunologia
16.
J Chem Phys ; 142(17): 174101, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25956084

RESUMO

A theoretical investigation on the origin dependence of the vibronic polarizabilities, isotropic and anisotropic rotational invariants, and scattering cross sections in Resonance Raman Optical Activity (RROA) spectroscopy is presented. Expressions showing the origin dependence of these polarizabilities were written in the resonance regime using the Franck-Condon (FC) and Herzberg-Teller (HT) approximations for the electronic transition moments. Differently from the far-from-resonance scattering regime, where the origin dependent terms cancel out when the rotational invariants are calculated, RROA spectrum can exhibit some origin dependence even for eigenfunctions of the electronic Hamiltonian. At the FC level, the RROA spectrum is completely origin invariant if the polarizabilities are calculated using a single excited state or for a set of degenerate states. Otherwise, some origin effects can be observed in the spectrum. At the HT level, RROA spectrum is origin dependent even when the polarizabilities are evaluated from a single excited state but the origin effect is expected to be small in this case. Numerical calculations performed for (S)-methyloxirane, (2R,3R)-dimethyloxirane, and (R)-4-F-2-azetidinone at both FC and HT levels using the velocity representation of the electric dipole and quadrupole transition moments confirm the predictions of the theory and show the extent of origin effects and the effectiveness of suggested ways to remove them.

17.
J Microencapsul ; 32(6): 538-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26218541

RESUMO

One possibility to obtain a higher dose of drug in a lower formulation volume can be by using of saturated quantity of drug in one of the phases of an emulsion. These formulations are called suspoemulsions (S/O/W). When a hydrophobic polymer is added to the organic phase of suspoemulsions, these formulations can be used to entrap the drug inside microspheres after in situ precipitation of the polymer-drug-excipients mix. In this work, performance and stability of progesterone suspensions in triacetin as organic phase of suspoemulsions were evaluated. These formulations were compared with O/W emulsions. Mathematical models were used to study in vitro release profiles. The results confirmed that S/O/W systems could be an attractive alternative to O/W formulations for the entrapment of progesterone inside poly(d,l-lactide-co-glycolide) microspheres. Diffusive-based models fit the in vitro release of progesterone from in situ-formed microspheres. For longer release periods, a time-dependent diffusion coefficient was successfully estimated.


Assuntos
Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Microesferas , Progesterona/administração & dosagem , Química Farmacêutica , Difusão , Portadores de Fármacos , Emulsões , Excipientes , Ácido Láctico/química , Modelos Teóricos , Poloxâmero/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/química , Polissorbatos/química , Progesterona/química , Triacetina/química
18.
J Comput Chem ; 35(4): 290-9, 2014 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-24403016

RESUMO

Simple procedures for the location of proper and improper rotations and reflexion planes are presented. The search is performed with a molecule divided into subsets of symmetrically equivalent atoms (SEA) which are analyzed separately as if they were a single molecule. This approach is advantageous in many aspects. For instance, in those molecules that are symmetric rotors, the number of atoms and the inertia tensor of the SEA provide one straight way to find proper rotations of any order. The algorithms are invariant to the molecular orientation and their computational cost is low, because the main information required to find symmetry elements is interatomic distances and the principal moments of the SEA. For example, our Fortran implementation, running on a single processor, took only a few seconds to locate all 120 symmetry operations of the large and highly symmetrical fullerene C720, belonging to the Ih point group. Finally, we show how the interatomic distances matrix of a slightly unsymmetrical molecule is used to symmetrize its geometry.

19.
J Spinal Disord Tech ; 27(8): 409-14, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23096129

RESUMO

STUDY DESIGN: Prospective observational study. OBJECTIVE: To assess patient quality of life before and after surgical treatment of adolescent idiopathic scoliosis (AIS) and determine whether an association exists between quality of life and curve magnitude, curve correction, and type of instrumentation. SUMMARY OF BACKGROUND DATA: Assessment of AIS surgery outcomes has always been based on analysis of radiographic measurements and postoperative curve correction. However, there is a current trend toward greater emphasis on patient-centered outcomes. Assessment of treatment success on the basis of these outcomes requires prospective use of quality-of-life surveys before and after AIS treatment. METHODS: Prospective study of 33 patients undergoing surgical treatment of AIS. Mean age was 15.6 years and mean Cobb angle was 70.5 degrees. Patients were randomly allocated into one of 2 instrumentation groups (hybrid and pedicle screws alone), and the Scoliosis Research Society-30 questionnaire (SRS-30) and Short Form-36 Health Survey (SF-36) questionnaires were administered preoperatively and at 3-, 6-, and 12-month follow-up. Statistical testing was performed to determine whether survey scores correlated with Cobb angle, curve correction, or type of instrumentation. RESULTS: SRS-30 and SF-36 scores improved significantly. The greatest changes occurred in the self-image and satisfaction with management domains of the SRS-30 survey. SRS-30 and SF-36 scores showed worsening pain and decreased function at 3-month follow-up, but significant improvement from baseline at 12 months. Total SRS-30 scores were significantly improved at 6- and 12-month follow-up, as were subscores in the general health, vitality, and social functioning domains of SF-36. Curve magnitude, percent curve correction, and type of instrumentation had no significant influence on final SRS-30 and SF-36 scores. CONCLUSIONS: Surgical treatment of AIS improved patient quality of life, as shown by significant improvement on all SRS-30 and SF-36 domains. Questionnaire scores did not correlate with Cobb angle, curve correction, or type of instrumentation.


Assuntos
Qualidade de Vida , Escoliose/psicologia , Escoliose/cirurgia , Adolescente , Parafusos Ósseos , Criança , Estudos de Coortes , Feminino , Seguimentos , Nível de Saúde , Humanos , Masculino , Satisfação do Paciente , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Radiografia , Escoliose/diagnóstico por imagem , Comportamento Social , Resultado do Tratamento , Adulto Jovem
20.
Mar Pollut Bull ; 203: 116407, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38701605

RESUMO

Cagarras Islands Archipelago, a no-take MPA in Southeast Brazil, was designated as Natural Monument (MONA Cagarras) and, more recently, recognized as Hope Spot for biodiversity conservation. This study aimed to assess plastic contamination by analyzing marine litter and microplastics in MONA Cagarras and surrounding waters. Marine litter (34.12 kg) was caught by artisanal fishermen in MONA Cagarras proximities, and plastics represented ∼79 %. Personal hygiene items and strains of hair were found, suggesting sewage-derived contamination from Ipanema SSO. Microplastics were detected in MONA Cagarras surface waters. Fragments and black particle were the most frequently found microplastic shape and color, respectively. µ-FTIR analysis identified, in descending order of occurrence, polystyrene-PS, polyethylene-PE, polyvinyl chloride-PVC, polypropylene-P, and polyamide-PA. Our integrated results of macro and microplastic contamination highlight an issue of effective conservation and health of marine biodiversity in MONA Cagarras and surrounding waters and a concern for better management of Brazilian MPAs.


Assuntos
Biodiversidade , Monitoramento Ambiental , Plásticos , Esgotos , Poluentes Químicos da Água , Brasil , Plásticos/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Microplásticos/análise , Ilhas , Conservação dos Recursos Naturais
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