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1.
Eur J Public Health ; 33(5): 803-808, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37390810

RESUMO

BACKGROUND: The healthy immigrant paradox has found wide support in the literature. To evaluate this hypothesis that immigrants have better health outcomes than the native population, this study aimed to compare the premature cancer mortality between the native and immigrant populations in Spain. METHODS: We obtained the 2012-15 cause-specific mortality estimates from administrative records and participant characteristics data from the 2011 Spanish census. Using Cox proportional hazards regression models, we calculated the risks of mortality of the native and immigrant populations, and the latter populations' risk based on their regions of origin, and determined the effects of covariates of interest on the calculated risk. RESULTS: Our results show that the risk of premature cancer mortality is lower among immigrants than among natives, and this gap is higher among men than among women. There is a lower mortality rate among Latin American immigrants (Latino men are 81% less likely to die prematurely from cancer than native-born men, and Latino women are 54% less). Moreover, despite social class disparities, immigrants' advantage in cancer mortality remained constant and decreased with increasing length of residence in the host country. CONCLUSIONS: This study provided novel evidence on the 'healthy immigrant paradox', associated with the fact that migrants are favorably selected at origin, cultural patterns of the societies of origin and, in the case of men, there is some convergence or an 'unhealthy' integration that explains the fact that this advantage over natives is lost with more years of residence in Spain.


Assuntos
Emigrantes e Imigrantes , Neoplasias , Masculino , Humanos , Feminino , Espanha/epidemiologia , Grupos Populacionais , Fatores de Risco
2.
ACS Omega ; 8(6): 5451-5463, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36816685

RESUMO

Synthetic dyes and chemicals create an enormous impact on environmental pollution both in textile manufacturing and after the product's lifetime. Biobased plant-derived colorants and mordants have great potential for the development of more sustainable textile dyeing processes. Colorants isolated from biomass residues are renewable, biodegradable, and usually less harmful than their synthetic counterparts. Interestingly, they may also bring additional functions to the materials. However, the extraction and purification of the biocolorants from biomass as well as their dyeing efficiency and color fastness properties require a more thorough examination. Here, we extracted red onion (Allium cepa) skins to obtain polyphenolic flavonoids and anthocyanins as biocolorants, characterized the chemical composition of the mixture, and used a quartz crystal microbalance and thin films of cellulose nanofibrils to study the adsorption kinetics of dyes onto cellulose substrates in situ. The effect of different mordants on the adsorption behavior was also investigated. Comparison of these results with conventional dyeing experiments of textiles enabled us to determine the interaction mechanism of the dyes with substrates and mordants. Chitosan showed high potential as a biobased mordant based both on its ability to facilitate fast adsorption of polyphenols to cellulose and its ability to retain the purple color of the red onion dye (ROD) in comparison to the metal mordants FeSO4 and alum. The ROD also showed excellent UV-shielding efficiency at low concentrations, suggesting that biocolorants, due to their more complex composition compared to synthetic ones, can have multiple actions in addition to providing aesthetics.

3.
Infect Dis Poverty ; 11(1): 89, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945552

RESUMO

BACKGROUND: Since the late twentieth century, Chagas disease gained global attention to suppress the vector burden as a main control strategy in endemic countries. In Central America, multi-national initiative successfully achieved significant reduction in the estimated disease prevalence as well as elimination of the region's principal vector species at the time in 2012. While the last decade has witnessed significant changes in ecosystem-such as urbanization and replacement of the main vector species-that can possibly affect the vector's habitation and residual transmission, the up-to-date vector burden in the region has not been evaluated thoroughly due to the cessation of active vector surveillance. The aim of this study was to update the risk of vector-borne Trypanosoma cruzi infection in El Salvador, the top Chagas disease-endemic country in Central America. METHODS: A nationwide vector survey was conducted in the domestic environment of El Salvador from September 2018 to November 2020. The selection of the houses for inspection was based on expert purposeful sampling. Infection for T. cruzi was examined by microscopic observation of the insects' feces, followed by a species confirmation using PCR. The data were analyzed using R software version 4.1.3. Proportion estimates with 95% confidence intervals were inferred using the Jeffrey's method provided under the epiR package. RESULTS: A total of 1529 Triatoma dimidiata was captured from 107 houses (infestation rate, 34.4%; 107/311) in all the fourteen departments of the country visited within the period; prevalence of T. cruzi infection was as high as 10% (153/1529). In the country, domestic T. dimidiata infestation was distributed ubiquitously, while T. cruzi infection rates varied across the departments. Five out of fourteen departments showed higher infection rates than the average, suggesting sporadic high-risk areas in the country. CONCLUSIONS: Our comprehensive study revealed substantial T. cruzi infection of T. dimidiata across the country, indicating potential active transmission of the disease. Therefore, strengthened surveillance for both vector and human infection is required to truly eliminate the risk of T. cruzi transmission in Central America.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Animais , Doença de Chagas/epidemiologia , Ecossistema , El Salvador/epidemiologia , Humanos , Insetos Vetores
4.
Saf Sci ; 130: 104866, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32834511

RESUMO

We provide research findings on the physics of aerosol and droplet dispersion relevant to the hypothesized aerosol transmission of SARS-CoV-2 during the current pandemic. We utilize physics-based modeling at different levels of complexity, along with previous literature on coronaviruses, to investigate the possibility of airborne transmission. The previous literature, our 0D-3D simulations by various physics-based models, and theoretical calculations, indicate that the typical size range of speech and cough originated droplets ( d ⩽ 20 µ m ) allows lingering in the air for O ( 1 h ) so that they could be inhaled. Consistent with the previous literature, numerical evidence on the rapid drying process of even large droplets, up to sizes O ( 100 µ m ) , into droplet nuclei/aerosols is provided. Based on the literature and the public media sources, we provide evidence that the individuals, who have been tested positive on COVID-19, could have been exposed to aerosols/droplet nuclei by inhaling them in significant numbers e.g. O ( 100 ) . By 3D scale-resolving computational fluid dynamics (CFD) simulations, we give various examples on the transport and dilution of aerosols ( d ⩽ 20 µ m ) over distances O ( 10 m ) in generic environments. We study susceptible and infected individuals in generic public places by Monte-Carlo modelling. The developed model takes into account the locally varying aerosol concentration levels which the susceptible accumulate via inhalation. The introduced concept, 'exposure time' to virus containing aerosols is proposed to complement the traditional 'safety distance' thinking. We show that the exposure time to inhale O ( 100 ) aerosols could range from O ( 1 s ) to O ( 1 min ) or even to O ( 1 h ) depending on the situation. The Monte-Carlo simulations, along with the theory, provide clear quantitative insight to the exposure time in different public indoor environments.

5.
ACS Nano ; 14(6): 6921-6930, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32426968

RESUMO

The complex nature of typical colloids and corresponding interparticle interactions pose a challenge in understanding their self-assembly. This specifically applies to biological nanoparticles, such as those obtained from chitin, which typically are hierarchical and multidimensional. In this study, we obtain chitin nanocrystals by one-step heterogeneous acid hydrolysis of never-dried crab residues. Partial deacetylation facilitates control over the balance of electrostatic charges (ζ-potential in the range between +58 and +75 mV) and therefore affords chitin nanocrystals (DE-ChNC) with axial aspect (170-350 nm in length), as determined by cryogenic transmission electron microscopy and atomic force microscopy. We find that the surface amines generated by deacetylation, prior to hydrolysis, play a critical role in the formation of individual chitin nanocrystals by the action of a dual mechanism. We directly access the twisting feature of chitin nanocrystals using electron tomography (ET) and uncover the distinctive morphological differences between chitin nanocrystals extracted from nondeacetylated chitin, ChNC, which are bundled and irregular, and DE-ChNC (single, straight nanocrystals). Whereas chitin nanocrystals obtained from dried chitin precursors are known to be twisted and form chiral nematic liquid crystals, our ET measurements indicate no dominant twisting or handedness for the nanocrystals obtained from the never-dried source. Moreover, no separation into typical isotropic and anisotropic phases occurs after 2 months at rest. Altogether, we highlight the critical role of drying the precursors or the nanopolysaccharides to develop chirality.

6.
Salud Publica Mex ; 62(2): 211-214, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-32237564

RESUMO

OBJECTIVE: To measure the effect of the change in mortality by AIDS in life expectancy at birth of Spanish population in 1985-2017. MATERIALS AND METHODS: We analyzed 56 863 deaths by AIDS. We calculated age-standardized death rates, and we applied Poisson regression and decomposition of life expectancies. RESULTS: From 1985 to 1995, mortality by AIDS contributed to reduce life expectancy at birth of 0.64 years for men, and 0.17 for women; in 1996-2017, increase it by 0.60 years, men, and 0.17, women. CONCLUSIONS: The introduction of highly active antiretroviral therapy in 1996 and prevention were decisive to reduce mortality by AIDS and to become chronic the epidemic.


OBJETIVO: Medir el efecto del cambio en mortalidad por sida en la esperanza de vida de la población española en 1985-2017. MATERIAL Y MÉTODOS: Se analizaron 56 863 defunciones por sida. Se calcularon tasas estandarizadas de mortalidad y se aplicó regresión de Poisson y descomposición de esperanzas de vida. RESULTADOS: En 1985-1995, la mortalidad por sida contribuyó a disminuir la esperanza de vida 0.64 años en hombres y 0.17 en mujeres. En 1996-2017, la hizo crecer 0.60 en hombres y 0.17 en mujeres. CONCLUSIONES: La introducción en 1996 de los tratamientos antirretrovirales de gran actividad y la prevención fueron decisivas para disminuir la mortalidad por sida y cronificar la epidemia.


Assuntos
Síndrome da Imunodeficiência Adquirida/mortalidade , Expectativa de Vida , Causas de Morte , Feminino , Humanos , Masculino , Espanha/epidemiologia
7.
Salud pública Méx ; 62(2): 211-214, mar.-abr. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1366004

RESUMO

Resumen: Objetivo: Medir el efecto del cambio en mortalidad por sida en la esperanza de vida de la población española en 1985-2017. Material y métodos: Se analizaron 56 863 defunciones por sida. Se calcularon tasas estandarizadas de mortalidad y se aplicó regresión de Poisson y descomposición de esperanzas de vida. Resultados: En 1985-1995, la mortalidad por sida contribuyó a disminuir la esperanza de vida 0.64 años en hombres y 0.17 en mujeres. En 1996-2017, la hizo crecer 0.60 en hombres y 0.17 en mujeres. Conclusión: La introducción en 1996 de los tratamientos antirretrovirales de gran actividad y la prevención fueron decisivas para disminuir la mortalidad por sida y cronificar la epidemia.


Abstract: Objective: To measure the effect of the change in mortality by AIDS in life expectancy at birth of Spanish population in 1985-2017. Materials and methods: We analyzed 56 863 deaths by AIDS. We calculated age-standardized death rates, and we applied Poisson regression and decomposition of life expectancies. Results: From 1985 to 1995, mortality by AIDS contributed to reduce life expectancy at birth of 0.64 years for men, and 0.17 for women; in 1996-2017, increase it by 0.60 years, men, and 0.17, women. Conclusion: The introduction of highly active antiretroviral therapy in 1996 and prevention were decisive to reduce mortality by AIDS and to become chronic the epidemic.


Assuntos
Feminino , Humanos , Masculino , Expectativa de Vida , Síndrome da Imunodeficiência Adquirida/mortalidade , Espanha/epidemiologia , Causas de Morte
8.
Biomacromolecules ; 20(7): 2770-2778, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31117356

RESUMO

Nanocellulose has been demonstrated as a suitable material for cell culturing, given its similarity to extracellular matrices. Taking advantage of the shear thinning behavior, nanocellulose suits three-dimensional (3D) printing into scaffolds that support cell attachment and proliferation. Here, we propose aqueous suspensions of acetylated nanocellulose of a low degree of substitution for direct ink writing (DIW). This benefits from the heterogeneous acetylation of precursor cellulosic fibers, which eases their deconstruction and confers the characteristics required for extrusion in DIW. Accordingly, the morphology of related 3D-printed architectures and their performance during drying and rewetting as well as interactions with living cells are compared with those produced from typical unmodified and TEMPO-oxidized nanocelluloses. We find that a significantly lower concentration of acetylated nanofibrils is needed to obtain bioinks of similar performance, affording more porous structures. Together with their high surface charge and axial aspect, acetylated nanocellulose produces dimensionally stable monolithic scaffolds that support drying and rewetting, required for packaging and sterilization. Considering their potential uses in cardiac devices, we discuss the interactions of the scaffolds with cardiac myoblast cells. Attachment, proliferation, and viability for 21 days are demonstrated. Overall, the performance of acetylated nanocellulose bioinks opens the possibility for reliable and scale-up fabrication of scaffolds appropriate for studies on cellular processes and for tissue engineering.


Assuntos
Celulose/química , Nanoestruturas/química , Impressão Tridimensional , Alicerces Teciduais/química , Acetilação/efeitos dos fármacos , Alginatos/síntese química , Alginatos/química , Alginatos/farmacologia , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Celulose/síntese química , Humanos , Nanofibras/química , Engenharia Tecidual
9.
J Phys Condens Matter ; 31(29): 295301, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30986776

RESUMO

In this work, we study structural and vibrational properties of multilayer graphene using density-functional theory with van der Waals (vdW) functionals. Initially, we analyze how different vdW functionals compare by evaluating the lattice parameters, elastic constants and vibrational frequencies of low energy optical modes of graphite. Our results indicate that the vdW-DF1-optB88 functional has the best overall performance on the description of vibrational properties. Next, we use this functional to study the influence of the vdW interactions on the structural and vibrational properties of multilayer graphene. Specifically, we evaluate binding energies, interlayer distances and phonon frequencies of layer breathing and shear modes. We observe excellent agreement between our calculated results and available experimental data, which suggests that this functional has truly predictive power for layer-breathing and shear frequencies that have not been measured yet. This indicates that careful selected vdW functionals can describe interlayer bonding in graphene-related systems with good accuracy.

10.
Carbohydr Polym ; 191: 44-52, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29661320

RESUMO

Chitosan is high potential material for new applications due to its properties, especially its antimicrobial activity, and because it is one of the most abundant natural polymers. However, chitosan can be processed only from solution limiting its applications. Methods for processing chitosan in molten have been a subject of recent interest. One method, involves thermoplastic its blends with poly(vinyl alcohol), however these blends undergo degradation due to acid residues from previous processing steps. Here we described a process to produce thermoplastic blends of poly(vinyl alcohol)-chitosan in a poly(lactic acid) matrix by avoiding degradation even at higher chitosan contents. The process involves the use of spray- and freeze-drying techniques to produce acid free blends of PVA/chitosan, then incorporated in PLA matrix by extrusion. These findings are expected to contribute to increasing and extending the applications of polysaccharides, such as chitosan, in new applications such as textiles, medical and food packing.

11.
Gac Sanit ; 32(2): 151-157, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-28529096

RESUMO

OBJECTIVE: To calculate and analyse the contributions of changes in mortality by age groups and selected causes of death to sex differences in life expectancy at birth in Spain from 1980 to 2012. METHODS: Cross-sectional study with three time points (1980, 1995, and 2012). We used data from Human Cause-of-Death Database and Human Mortality Database. We use a decomposition method of the differences in life expectancy and gender differences in life expectancy from changes in mortality by 5-year age groups and causes of death between women and men. RESULTS: From 1980 to 1995, the lower mortality of women from 25 years old, and the differences in mortality by HIV/AIDS, lung cancer, and chronic obstructive pulmonary diseases contributed to the gap increase. From 1995 to 2012, greatest improvement in mortality of males under 74 years of age, and in improving male mortality from HIV/AIDS, acute myocardial infarction and traffic accidents contributed to the narrowing. CONCLUSIONS: The difference in life expectancy at birth between men and women has decreased since 1995 due to a greater improvement in mortality from causes of death associated with risky behaviours and habits of the working age male population.


Assuntos
Fatores Etários , Causas de Morte/tendências , Expectativa de Vida/tendências , Mortalidade/tendências , Fatores Sexuais , Acidentes/mortalidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Doença , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo , Espanha/epidemiologia , Adulto Jovem
12.
Biomacromolecules ; 12(4): 907-14, 2011 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-21361270

RESUMO

Ternary compatible blends of chitosan, poly(vinyl alcohol), and poly(lactic acid) were prepared by an oil-in-water (O/W) emulsion process. Solutions of chitosan in aqueous acetic acid, poly(vinyl alcohol) (PVA) in water, and poly(lactic acid) (PLA) in chloroform were blended with a high-shear mixer. PVA was used as an emulsifier to stabilize the emulsion and to reduce the interfacial tension between the solid polymers in the blends produced. It proved to work very well because the emulsions were stable for periods of days or weeks and compatible blends were obtained when PVA was added. This effect was attributed to a synergistic effect of PVA and chitosan because the binary blends PVA/PLA and chitosan/PLA were completely incompatible. The blends were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermal mechanical analysis (TMA), stress-strain tests, and Fourier transform infrared spectroscopy (FTIR). The results indicated that despite the fact that the system contained distinct phases some degree of molecular miscibility occurred when the three components were present in the blend.


Assuntos
Quitosana/química , Emulsões , Ácido Láctico/química , Polímeros/química , Álcool de Polivinil/química , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Óleos , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier
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