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1.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1301-1308, Nov.-Dec. 2021. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355670

RESUMO

The objective was to evaluate the antioxidant capacity, glucose and insulin concentration and reproductive performance of ewes supplemented with orange residue prior to insemination. Fifty-five multiparous ewes were divided into two corrals, and 15 unbred ewes were kept individually to measure feed consumption. Two integral diets were administered; T0: control treatment and T1: with 20% of dry matter of orange residue. Ten days after the start of supplementation, the ewes were synchronized. Supplementation was finalized prior to artificial insemination, then, a blood sample was taken to measure the antioxidant capacity and glucose and insulin concentration. An analysis of variance was made to evaluate the effect of treatment on the antioxidant capacity, glucose and insulin; and to analyze the response to estrus, percentage of gestation and prolificity a ji squared test was performed. Of 9 antioxidant compounds found in the orange residue, hesperidin (7.44%), chlorogenic acid (0.50%) and protocatechuic acid had the highest concentration. Feed intake, estrus response, percentage of gestation, antioxidant capacity, and glucose and insulin concentration were not affected by the treatment. It is concluded that inclusion of 20% of orange residue in the diet prior to insemination in ewes is possible.(AU)


O objetivo deste estudo foi avaliar a capacidade antioxidante, a concentração de glicose e insulina e o comportamento reprodutivo de ovelhas suplementadas com resíduo de laranja antes da inseminação. Cinquenta e cinco ovelhas multíparas foram divididas em dois currais e 15 ovelhas sem raça foram mantidas individualmente para se medir o consumo de ração. Duas dietas integrais foram administradas; T0: tratamento controle e T1: dieta com 20% de resíduo de laranja seco. Dias após o início da suplementação, as ovelhas foram sincronizadas. A suplementação foi finalizada antes da inseminação artificial e, em seguida, foi coletada uma amostra de sangue para medir a capacidade antioxidante e a concentração de glicose e insulina. Uma análise de variância foi feita para avaliar o efeito do tratamento sobre a capacidade antioxidante, a glicose e a insulina, e um teste do ji quadrado foi realizado para analisar a resposta ao estro, a porcentagem de gestação e de prolificidade. Dos nove compostos antioxidantes encontrados no resíduo laranja, a hesperidina (7,44%), o ácido clorogênico (0,50%) e o ácido protocatecuico foram os de maior concentração. O consumo alimentar, a resposta ao estro, a porcentagem de gestação, a capacidade antioxidante, a concentração de glicose e a insulina não foram afetados pelo tratamento. Conclui-se que é possível a inclusão de 20% de resíduos de laranja na dieta antes da inseminação em ovelhas.(AU)


Assuntos
Animais , Feminino , Glicemia/análise , Ovinos/fisiologia , Citrus sinensis/metabolismo , Sincronização do Estro/métodos , Insulinas/análise , Antioxidantes/análise , Inseminação Artificial/veterinária , Resíduos de Alimentos
2.
Sci Rep ; 11(1): 5474, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750828

RESUMO

Exchange bias properties of MnFe[Formula: see text]O[Formula: see text]@[Formula: see text]-Fe[Formula: see text]O[Formula: see text] core-shell nanoparticles are investigated. The measured field and temperature dependencies of the magnetization point out a well-ordered ferrimagnetic core surrounded by a layer with spin glass-like arrangement. Quasi-static SQUID magnetization measurements are presented along with high-amplitude pulse ones and are cross-analyzed by comparison against ferromagnetic resonance experiments at 9 GHz. These measurements allow one to discern three types of magnetic anisotropies affecting the dynamics of the magnetic moment of the well-ordered ferrimagnetic NP's core viz. the easy-axis (uniaxial) anisotropy, the unidirectional exchange-bias anisotropy and the rotatable anisotropy. The uniaxial anisotropy originates from the structural core-shell interface. The unidirectional exchange-bias anisotropy is associated with the spin-coupling at the ferrimagnetic/spin glass-like interface; it is observable only at low temperatures after a field-cooling process. The rotatable anisotropy is caused by partially-pinned spins at the core/shell interface; it manifests itself as an intrinsic field always parallel to the external applied magnetic field. The whole set of experimental results is interpreted in the framework of superparamagnetic theory, i.e., essentially taking into account the effect of thermal fluctuations on the magnetic moment of the particle core. In particular, it is found that the rotatable anisotropy of our system is of a uniaxial type.

3.
J Nanosci Nanotechnol ; 19(8): 4888-4902, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913800

RESUMO

In this paper we review the magnetic properties of spinel ferrite nanoparticles pointing out the primary role of the crystalline structure besides finite size and surface/interface effects. The details of the spinel crystal structure of bulk spinel ferrite materials and their influence on both the magnetization and magnetocrystalline anisotropy are recalled. Moreover, we review some results published in the literature over the last years about how the structure of magnetic nanoparticles influences their magnetic features. Perspectives about the challenges to improve the applications in several fields are finally reported.

4.
J Phys Condens Matter ; 31(17): 175801, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30699398

RESUMO

We compare both magnetic blocking properties and remanence curves for dilute ferrofluid and powder samples of ferrite magnetic nanoparticles. Low field DC magnetization, AC susceptibility, isothermal remanent magnetization and DC demagnetization techniques are employed to investigate the role of interparticle magnetic interactions on the superparamagnetic relaxation, the magnetic anisotropy and on the super-spin-glass state in closely packed particles. The samples used herein are 3 nm sized spinel-type nanocrystals made of a cobalt ferrite core covered by a layer of maghemite on its outermost surface and can be obtained as aqueous colloidal dispersions thanks to this core-shell strategy. They show large anisotropy attributed to an enhanced surface contribution and the blocking temperature is shifted towards higher values as interparticle distance decreases. For all investigated diluted liquids and powder samples the frequency dependency of the peak temperature is well accounted by a Vogel-Fulcher law, with the insertion of a phenomenological temperature associated to the magnitude of interparticle dipolar interactions. The fractional change of the peak temperature per decade of frequency enlights the presence of interactions between particles in dilute liquids and of a spin-glass-like state in powder samples. The remanence curves always show global demagnetizing behavior, attributed to the combination of both spin surface disorder and interparticle dipolar interactions, the former being predominant in isolated nanoparticles and the latter in powder samples. However, in the most compacted powder, exchange interaction between surface ions of different particles becomes more pronounced and promotes an additive magnetizing effect.

5.
Phys Chem Chem Phys ; 20(24): 16402-16413, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29873364

RESUMO

Thermodiffusion of different ferrite nanoparticles (NPs), ∼10 nm in diameter, is explored in tailor-made aqueous dispersions stabilized by electrostatic interparticle interactions. In the dispersions, electrosteric repulsion is the dominant force, which is tuned by an osmotic-stress technique, i.e. controlling of osmotic pressure Π, pH and ionic strength. It is then possible to map Π and the NPs' osmotic compressibility χ in the dispersion with a Carnahan-Starling formalism of effective hard spheres (larger than the NPs' core). The NPs are here dispersed with two different surface ionic species, either at pH ∼ 2 or 7, leading to a surface charge, either positive or negative. Their Ludwig-Soret ST coefficient together with their mass diffusion Dm coefficient are determined experimentally by forced Rayleigh scattering. All probed NPs display a thermophilic behavior (ST < 0) regardless of the ionic species used to cover the surface. We determine the NPs' Eastman entropy of transfer and the Seebeck (thermoelectric) contribution to the measured Ludwig-Soret coefficient in these ionic dispersions. The NPs' Eastman entropy of transfer sNP is interpreted through the electrostatic and hydration contributions of the ionic shell surrounding the NPs.

6.
Hum Immunol ; 79(7): 578-582, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29684412

RESUMO

Neurocysticercosis (NC) is caused by the establishment of the metacestode stage of Taenia solium in the human central nervous system. A great heterogeneity in the susceptibility to the infection and to the disease has been reported. While the factors involved in this heterogeneity are not completely understood, clearly different immune-inflammatory profiles have been associated to each condition. This study evaluated the association of cytokine single nucleotide polymorphisms (SNPs) with susceptibility to infection and disease severity in NC patients. Blood samples from 92 NC cases and their parents (trios) were genotyped for SNPs in five cytokines relevant for the immune response: IL4 (-589C/T), IL6 (-174C/G), IFNG (+874T/A), TNF (-238G/A), and IL2 (-330G/T). Specific DNA fragments were amplified by the polymerase chain reaction, using the 5'-nuclease Taqman assay on a 7500 platform, allowing the detection of the polymorphism genotypes. No association between the polymorphisms evaluated neither with susceptibility to infection nor with disease severity was found, although previous studies reported variations in the levels of these cytokines among different NC clinical pictures. These results, nevertheless, add new elements to our understanding of the complex pathogenic mechanisms involved in susceptibility to infection by T. solium cysticerci and the severity of the ensuing disease.


Assuntos
Sistema Nervoso Central/parasitologia , Interferon gama/genética , Interleucina-2/genética , Interleucina-4/genética , Interleucina-6/genética , Neurocisticercose/genética , Taenia solium/fisiologia , Teníase/genética , Fator de Necrose Tumoral alfa/genética , Animais , Progressão da Doença , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Linhagem , Polimorfismo de Nucleotídeo Único
7.
J Phys Chem A ; 121(30): 5728-5734, 2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28686436

RESUMO

In this paper, an augmented all-electron double-ζ basis set is used in calculations of the structure and electronic properties of small niobium clusters. The B3PW91 and M06 DFT functionals with and without second order Douglas-Kroll-Hess (DKH) scalar relativistic corrections are also utilized. Furthermore, an additional d Gaussian type function is introduced in the standard basis sets in order to improve the description of the clusters orbitals in the valence band. Our findings show that the extra d function is important to yield accurate results of electronic properties and, in addition, the DKH corrections can be relevant when the all-electron basis sets are used in the calculations. Our best results are obtained with the M06 functional together with the DKH second order corrections and with the extra d function added to the all-electron basis set.

8.
Int J Tuberc Lung Dis ; 21(7): 790-796, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28633704

RESUMO

OBJECTIVE: To evaluate the impact of the Brazilian cash transfer programme (Bolsa Família Programme, BFP) on tuberculosis (TB) incidence in Brazil from 2004 to 2012. DESIGN: We studied tuberculosis surveillance data using a combination of an ecological multiple-group and time-trend design covering 2458 Brazilian municipalities. The main independent variable was BFP coverage and the outcome was the TB incidence rate. All study variables were obtained from national databases. We used fixed-effects negative binomial models for panel data adjusted for selected covariates and a variable representing time. RESULTS: After controlling for covariates, TB incidence rates were significantly reduced in municipalities with high BFP coverage compared with those with low and intermediate coverage (in a model with a time variable incidence rate ratio = 0.96, 95%CI 0.93-0.99). CONCLUSION: This was the first evidence of a statistically significant association between the increase in cash transfer programme coverage and a reduction in TB incidence rate. Our findings provide support for social protection interventions for tackling TB worldwide.


Assuntos
Modelos Estatísticos , Assistência Pública , Tuberculose/epidemiologia , Brasil/epidemiologia , Cidades , Humanos , Incidência , Vigilância da População , Pobreza , Fatores de Tempo , Tuberculose/prevenção & controle
9.
Drug Dev Ind Pharm ; 42(7): 1127-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26556126

RESUMO

Idebenone is a high permeable drug with very slight water solubility that affects the dissolution rate in the biological fluids, causing an irregular and limited in vivo absorption after oral administration. Moreover, it is marketed in Europe as tablets equivalent to 150 mg, with the consequent administration of multiple dose of solid unit to obtain the correct dose, a deterrent for the patients' compliance. According to these considerations, our goal was to develop spray-dried microparticles using a soluble ß-cyclodextrin (CD) polymer and an enhancer of dissolution rate, such as carboxymethyl cellulose, to obtain a formulation easily dosable and soluble in water. The complex in solution was evaluated by phase solubility studies and the Idebenone/CD molar ratio selected was 1:1. According to Higuchi and Connors, adding carboxymethyl cellulose, a Bs-type profile was obtained. This result was due to the presence of carboxymethyl cellulose that competes with the CD in forming Idebenone microsystems, reducing of 10-fold the formulation bulk. UV-Vis absorption, (1)H nuclear magnetic resonance and circular dichroism showed the formation of the CD/Idebenone inclusion complex confirmed also by differential scanning calorimetry, Fourier transform infrared spectroscopy and fluorescence microscope (FM). The water solubility data and the in vitro dissolution tests performed in simulated gastric fluid, showed an increase of the drug water interaction due to the presence of the CD and carboxymethyl cellulose, both able to improve drug wettability, water solubility and dissolution rate. This approach seems to be suitable to produce microsystems which are able to enhance the in vivo absorption of Idebenone after oral administration and to increase the patient compliance.


Assuntos
Antioxidantes/administração & dosagem , Celulase/química , Cooperação do Paciente , Tecnologia Farmacêutica/métodos , Ubiquinona/análogos & derivados , beta-Ciclodextrinas/química , Administração Oral , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos , Estabilidade de Medicamentos , Humanos , Ubiquinona/administração & dosagem , Ubiquinona/química
10.
Artigo em Inglês | MEDLINE | ID: mdl-26565244

RESUMO

The temperature dependence of the Soret coefficient S(T)(T) in electrostatically charged magnetic colloids is investigated. Two different ferrofluids, with different particles' mean dimensions, are studied. In both cases we obtain a thermophilic behavior of the Soret effect. The temperature dependence of the Soret coefficient is described assuming that the nanoparticles migrate along the ionic thermoelectric field created by the thermal gradient. A model based on the contributions from the thermoelectrophoresis and variation of the double-layer energy, without fitting parameters, is used to describe the experimental results of the colloid with the bigger particles. To do so, independent measurements of the ζ potential, mass diffusion coefficient, and Seebeck coefficient are performed. The agreement of the theory and the experimental results is rather good. In the case of the ferrofluid with smaller particles, it is not possible to get experimentally reliable values of the ζ potential and the model described is used to evaluate this parameter and its temperature dependence.

11.
Artigo em Inglês | MEDLINE | ID: mdl-25974501

RESUMO

Magnetic fluids based on manganese ferrite nanoparticles were studied from the structural point of view through small angle x-rays scattering (SAXS) and from the magnetic point of view through zero-field cooling and field cooling (ZFC-FC) and ac susceptibility measurements (MS). Three different colloids with particles mean diameters of 2.78,3.42, and 6.15 nm were investigated. The size distribution obtained from SAXS measurements follows a log-normal behavior. The ZFC-FC and MS results revealed the presence of an important magnetic interaction between the nanoparticles, characterized by a magnetic correlation distance Λ. The colloidal medium can be pictures as composed by magnetic cluster constituted by N interacting particles. These magnetic clusters are not characterized by a physical aggregation of particles. The energy barrier energy obtained is consistent with the existence of this magnetic clusters. Besides the magnetic interaction between particles, confinement effects must be included to account for the experimental values of the magnetic energy barrier encountered.

12.
Artigo em Inglês | MEDLINE | ID: mdl-24730843

RESUMO

The Soret coefficient (ST) of positively charged magnetic colloids was measured as a function of the nanoparticles' diameter. The Z-scan technique and the generalization of the thermal lens model proved to be a reliable technique to measure ST. We show that ST is negative and increases with the particle's diameter, being best described by a functional dependence of the type ST∝d0. Potentiometric and conductometric experiments show that the particle's surface charge decreases as the temperature increases, changing the electrostatic interaction between the nanoparticles. The temperature gradient imposed in the ferrofluid by the Gaussian laser beam leads to the formation of the particle's concentration gradient. The origin of this phenomenon is discussed in terms of the decrease of the particle's surface charge in the hottest region of the sample and the thermoelectric field due to the inhomogeneous distribution of hydrogenous ions present in the colloidal suspension.

13.
Arq. bras. med. vet. zootec ; 66(2): 563-572, Jan.-Apr. 2014. graf, tab
Artigo em Português | LILACS | ID: lil-709298

RESUMO

O presente estudo foi conduzido para determinar o consumo e a digestibilidade dos nutrientes, bem como o comportamento ingestivo de cordeiros Somalis Brasileira, alimentados com diferentes níveis de energia metabolizável (EM). Foram utilizados 40 animais, não castrados, com peso vivo médio de 13,47±1,76kg. Os animais foram distribuídos em delineamento em blocos ao acaso, com cinco dietas com diferentes níveis de energia metabolizável (1,18; 2,07; 2,25; 2,42 e 2,69Mcal/kg de MS). O consumo de MS, PB, FDN, CF (g/dia), MS (g/kg0,75) e FDN (%PC e g/kg0,75) apresentaram efeito quadrático (P<0,05), assim como os coeficientes de digestibilidade (P<0,05) da PB, da FDN e dos CF. Foi averiguado efeito linear crescente (P<0,05) para digestibilidade da MS, da MO e dos CNF com o aumento da EM na dieta. Os tempos de alimentação e ócio (h/dia) foram influenciados pelos níveis de energia (P<0,05), e as eficiências de alimentação e ruminação (g FDN/h) apresentaram efeito quadrático (P<0,05). Conclui-se que o aumento dos níveis de EM das rações influencia o consumo e a digestibilidade dos nutrientes, bem como o comportamento ingestivo de cordeiros Somalis Brasileira...


The study was conducted to determine the intake, nutrient digestibility and ingestive behavior of Brazilian Somali lambs fed different levels of metabolizable energy (ME). Forty non-castrated Brazilian Somali lambs with average weight of 13.47±1.76kg were used. The animals were assigned to a randomized block design with eight replications per block and five diets with increasing metabolizable energy (1.18, 2.07, 2.25, 2.42 and 2.69 Mcal/kg DM). The quadratic effect (P<0.05) of the ME level was determined for DM, CP, NDF and FC (g/day) and DM (g/kg0,75) and NDF(%PC and g/kg0,75) intake, as well as the digestibility coefficients (P<0.05) for CP, NDF and CF. A linear effect (P<0.05) was observed for digestibility of DM, OM and NFC with the increase of ME in the diet. Eating and idle results (hours/day) were influenced by the energy levels (P<0.05) and efficiencies of feeding and rumination (g NDF/h) showed a quadratic effect (P<0.05). It is concluded that the increase of ME levels in the diet influences intatke, nutrient digestibility and ingestive behavior of Brazilian Somali lambs...


Assuntos
Animais , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Ingestão de Alimentos , Metabolismo Energético/fisiologia , Nutrientes , Ovinos/metabolismo , Absorção , Digestão/fisiologia , Fatores de Tempo
14.
Eur Phys J E Soft Matter ; 36(4): 9856, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23612746

RESUMO

In this work we focus on the surface charging properties of core shell ferrite nanoparticles dispersed in water, namely magnetic nanocolloids. This structural charge results from the Brönsted acid-base behavior of the particles surface sites and is achieved through hydrolysis reactions. It can be modeled by considering identical charged sites behaving as weak diprotic acids. Then, electrochemical techniques could be implemented to study the acid-base equilibrium between the particle surface and the colloid bulk solution. Simultaneous potentio-conductimetric titrations are therefore performed to determine the thermodynamical constants of the p H-dependent reactions and to obtain the p H variations of the surface charge density. The results reveal that the saturation value of the structural charge strongly depends on the nanoparticle mean size. For large particles, the surface tends to be fully ionized whereas for smaller particles the saturated structural charge decreases drastically. This surface charge reduction is attributed to the existence in smaller particles of metallic surface sites, which cannot be accessible to the proton charge. The existence of such dead sites would be related to hydroxo-bonded sites with very low acidity combined with a quantum size effect, which would affect the charging/discharging process at the surface of the semiconductor ferrite quantum dot.

15.
J Hosp Infect ; 83(3): 200-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23374287

RESUMO

BACKGROUND: The increase in opportunistic fungal infections has led to the search for putative sources of contamination in hospital environments. AIM: Ants in a public hospital in Itabuna, north-eastern Brazil were examined for carriage of filamentous fungi. METHODS: During a year-long survey, ants from different hospital areas were sampled. Preference was given to locations where it was possible to observe ants actively foraging. The fungi found on the ants' integument were cultured and identified. FINDINGS: A total of 106 ant workers belonging to 12 species in 11 genera were collected. A total of 47 fungal strains was isolated from 40% of the ants (N = 42). We found 16 fungal species in 13 genera associated with the ant workers. The prevalent fungal genera were Aspergillus, Purpureocillium and Fusarium. The ants Tapinoma melanocephalum, Paratrechina longicornis and Pheidole megacephala were associated with six fungal genera; and four genera of fungi were associated with Solenopsis saevissima workers. Fungal diversity was higher in the following hospital areas: nursery, hospital beds, breastmilk bank and paediatrics. CONCLUSION: Ants act as carriers of soil and airborne fungal species, and ant control in hospital areas is necessary to prevent the dissemination of such micro-organisms.


Assuntos
Formigas/microbiologia , Fungos/classificação , Fungos/isolamento & purificação , Insetos Vetores , Animais , Brasil , Hospitais Públicos
16.
Eur Cell Mater ; 24: 426-40, 2012 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-23180452

RESUMO

Stem cell migration is a critical step during the repair of damaged tissues. In order to achieve appropriate cell-based therapies for tooth and periodontal ligament repair it is necessary first to understand the dynamics of tissue-specific stem cell populations such as dental pulp stem cells (DPSC) and dental follicle stem cells (DFSC). Using time-lapse imaging, we analysed migratory and proliferative capabilities of these two human stem cell lines in vitro. When cultured alone, both DPSC and DFSC exhibited low and irregular migration profiles. In co-cultures, DFSC, but not DPSC, spectacularly increased their migration activity and velocity. DFSC rapidly surrounded the DPSC, thus resembling the in vivo developmental process, where follicle cells encircle both dental epithelium and pulp. Cell morphology was dependent on the culture conditions (mono-culture or co-culture) and changed over time. Regulatory genes involved in dental cell migration and differentiation such as TWIST1, MSX1, RUNX2, SFRP1 and ADAM28, were also evaluated in co-cultures. MSX1 up-regulation indicates that DPSC and DFSC retain their odontogenic potential. However, DPSC lose their capacity to differentiate into odontoblasts in the presence of DFSC, as suggested by RUNX2 up-regulation and TWIST1 down-regulation. In contrast, the unchanged levels of SFRP1 expression suggest that DFSC retain their potential to form periodontal tissues even in the presence of DPSC. These findings demonstrate that stem cells behave differently according to their environment, retain their genetic memory, and compete with each other to acquire the appropriate territory. Understanding the mechanisms involved in stem cell migration may lead to new therapeutic approaches for tooth repair.


Assuntos
Movimento Celular , Polpa Dentária/citologia , Saco Dentário/citologia , Células-Tronco/citologia , Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Diferenciação Celular , Linhagem Celular , Técnicas de Cocultura , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Polpa Dentária/metabolismo , Saco Dentário/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fator de Transcrição MSX1/genética , Fator de Transcrição MSX1/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Células-Tronco/metabolismo , Transcrição Gênica , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo
17.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 10(1): 5-13, jun. 2012. tab, graf
Artigo em Espanhol | LILACS, BDNPAR | ID: lil-663638

RESUMO

Este estudio observacional descriptivo de corte transverso tuvo por objetivo estandarizar una PCR múltiple para la detección simultánea de los genes mecA y pvl en Staphylococcus spp. Se emplearon como cepas control: S. aureus ATCC 25923, S. aureus ATCC 43300 y un aislado de S. aureus portador de los genes mecA y pvl. La extracción de ADN se realizó por el método de ebullición. El límite de detección se estableció por medio de diluciones seriadas de ADN. Se determinó la aplicabilidad de la PCR múltiple testando 41 aislados de S. aureus y 51 Estafilococos coagulasa negativo (ECN) previamente caracterizados por métodos fenotípicos en noviembre del año 2009. Los productos de PCR fueron visualizados por electroforesis en gel de agarosa al 2% previa tinción con bromuro de etidio. Los productos de amplificación de la PCR múltiple presentaron tamaño esperado de 533pb y 433pb para los genes mecA y pvl respectivamente, con límites de detección de hasta 0,5 ng/µL. El gen mecA se detectó en 13 (31,7%) aislados de S. aureus y en 29 (56,7%) ECN. El gen pvl se detectó en 2 (4,9%) S. aureus y no fue detectado en ECN. La presencia del gen mecA tuvo 100% de concordancia con los métodos fenotípicos. Esta técnica es una herramienta útil en la confirmación de cepas de Estafilococos meticilino resistentes e identificación del gen pvl, además de ser relativamente sencilla con la ventaja de detectar ambos genes en una sola reacción


Assuntos
Coagulase , Staphylococcus aureus
18.
Int J Pharm ; 426(1-2): 100-107, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22301426

RESUMO

The high hygroscopicity of gentamicin (G) as raw material hampers the production of respirable particles during aerosol generation and prevents its direct use as powder for inhalation in patients suffering from cystic fibrosis (CF). Therefore, this research aimed to design a new dry powder formulation of G studying dispersibility properties of an aminoacid, L-leucine (leu), and appropriate process conditions. Spray-dried powders were characterized as to water uptake, particle size distribution, morphology and stability, in correlation with process parameters. Aerodynamic properties were analyzed both by Single Stage Glass Impinger and Andersen Cascade Impactor. Moreover, the potential cytotoxicity on bronchial epithelial cells bearing a CFTR F508/F508 mutant genotype (CuFi1) were tested. Results indicated that leu may improve the aerosol performance of G-dried powders. The maximum fine particle fraction (FPF) of about 58.3% was obtained when water/isopropyl alcohol 7:3 system and 15-20% (w/w) of leu were used, compared to a FPF value of 13.4% for neat G-dried powders. The enhancement of aerosol efficiency was credited both to the improvement of the powder flowability, caused by the dispersibility enhancer (aminoacid), and to the modification of the particle surface due to the influence of the organic co-solvent on drying process. No significant degradation of the dry powder was observed up to 6 months of storage. Moreover, particle engineering did not affect either the cell viability or cell proliferation of CuFi1 over a 24 h period.


Assuntos
Antibacterianos/química , Antibacterianos/toxicidade , Inaladores de Pó Seco , Excipientes/química , Excipientes/toxicidade , Gentamicinas/química , Gentamicinas/toxicidade , Leucina/química , Leucina/toxicidade , Mucosa Respiratória/efeitos dos fármacos , 2-Propanol/química , Administração por Inalação , Aerossóis , Antibacterianos/administração & dosagem , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Relação Dose-Resposta a Droga , Composição de Medicamentos , Estabilidade de Medicamentos , Gentamicinas/administração & dosagem , Humanos , Mutação , Tamanho da Partícula , Pós , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Medição de Risco , Solventes/química , Tecnologia Farmacêutica/métodos , Fatores de Tempo , Água/química
19.
Int. j. morphol ; 29(1): 57-64, Mar. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-591950

RESUMO

Clinically significant chromosomal abnormalities occur in about 1 percent of children born alive. The objective of this work was to offer the patients and the families in the community for the service of the Integrated Clinic of Uniara Health (Araraquara and region), the examination of cariotype (cytogenetic study) for confirmation or exclusion of the diagnostic suspicion of chromosomal abnormalities as well as information (genetic counseling) for the prevention of occurrence and/or recurrence of these anomalies. In the period of one year and four months these were carried out in the Integrated Clinic of Uniara Health and directed for the Laboratory of Cytogenetic Human of the same institution in 66 cytogenetic studies. In 44 patients (66.6 percent) the results were normal. In 22 (33.3 percent) examinations, alterations were found, meaning that the respective clinical pictures are decurrent of chromosomic alterations. The first cause within alterations noted was Down syndrome with a total of 15 examinations or 68.1 percent, the second cause of chromosomal anomaly was the Turner syndrome where the most important factor is 45, X, where 2 karyotypes of this type or 9.1 percent were found, syndromes as (Eduards syndrome, Patau syndrome, 3p- syndrome, 4p- syndrome and 6p-syndrome) diagnosed in our laboratory appeared less frequently corresponding to 22.7 percent of the studied anomalies. The work carried out constitutes a necessary diagnosis of the main chromosomal abnormalities through a low cost technique; it can be carried out easily and is reliable, making the cytogenetic examination available to the community and contributing significantly to the quality of life of patients.


Las anormalidades cromosómicas, clínicamente significativas, se presentan en aproximadamente 1 por ciento de los niños nacidos vivos. Este trabajo tiene el objetivo de ofrecer a los pacientes y /o a sus familiares el servicio de la Clínica Integrada de la Salud de Uniara (Araraquara y Región), el examen de cariotipo (estudio citogenético) para la confirmación o la exclusión de sospecha de anomalías cromosomales diagnosticadas, así como otorgar información (consejo genético) para la prevención de las posibles anomalías y /o la repetición de éstas. En un año y cuatro meses fueron realizados 66 estudios de citogenética en la Clínica Integrada de Uniara, dirigida por el Laboratorio de Citogenética Humana de la misma institución. En 44 pacientes (66,6 por ciento) los resultados fueron normales. En 22 (33,3 por ciento) de los exámenes, se encontraron alteraciones, compatibles con alteraciones cromosómicas. La primera causa de anomalías cromosómica fue el síndrome de Down, totalizando 15 exámenes (68,1 por ciento), la segunda causa fue el síndrome de Turner, con dos cariotipos (9,1 por ciento) en la forma más importante 45, X. Por otra parte, se encontró que los síndromes de Eduards, de Patau, 3p-síndrome de Down, síndrome 4p-6p, diagnosticados en nuestro laboratorio, presentaban baja frecuencia de aparición, representando el 22,7 por ciento de las anomalías estudiadas. Este trabajo permitió realizar un diagnóstico preciso de las anomalías cromosomales, principalmente a través de una técnica de bajo costo, fácil ejecución y buena confiabilidad, técnicas que están disponibles para el examen citogenético para la comunidad y así contribuir de manera significativa en la calidad de vida de los pacientes.


Assuntos
Humanos , Masculino , Feminino , Aberrações Cromossômicas/classificação , Aberrações Cromossômicas/estatística & dados numéricos , Síndrome de Down/diagnóstico , Síndrome de Down/embriologia , Síndrome de Down/genética , Síndrome de Down/sangue , Síndrome de Turner/diagnóstico , Síndrome de Turner/genética , Síndrome de Turner/sangue , Análise Citogenética/métodos , Aconselhamento Genético/estatística & dados numéricos , Aconselhamento Genético/métodos
20.
Eur Cell Mater ; 20: 295-305, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20931491

RESUMO

Dental pulp stem cells (DPSCs) are multipotent stem cells derived from neural crest and mesenchyme and have the capacity to differentiate into multiple cell lineages. It has already been demonstrated that DPSCs differentiate into melanocyte-like cells but only when cultivated in a specific melanocyte differentiating medium. In this study we have shown, for the first time, that DPSCs are capable of spontaneously differentiating into mature melanocytes, which display molecular and ultrastructural features of full development, including the expression of melanocyte specific markers and the presence of melanosomes up to the terminal stage of maturation. We have also compared the differentiating features of DPSCs grown in different culture conditions, following the timing of differentiation at molecular and cytochemical levels and found that in all culture conditions full development of these cells was obtained, although at different times. The spontaneous differentiating potential of these cells strongly suggests their possible applications in regenerative medicine.


Assuntos
Diferenciação Celular , Polpa Dentária/citologia , Melanócitos/citologia , Células-Tronco Mesenquimais/citologia , Linhagem da Célula , Células Cultivadas , Polpa Dentária/metabolismo , Humanos , Melanócitos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/ultraestrutura , Microscopia Eletrônica de Transmissão
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