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1.
BMC Biol ; 20(1): 233, 2022 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-36266680

RESUMEN

BACKGROUND: Lipid homeostasis is an evolutionarily conserved process that is crucial for energy production, storage and consumption. Drosophila larvae feed continuously to achieve the roughly 200-fold increase in size and accumulate sufficient reserves to provide all energy and nutrients necessary for the development of the adult fly. The mechanisms controlling this metabolic program are poorly understood. RESULTS: Herein we identified a highly conserved gene, orsai (osi), as a key player in lipid metabolism in Drosophila. Lack of osi function in the larval fat body, the regulatory hub of lipid homeostasis, reduces lipid reserves and energy output, evidenced by decreased ATP production and increased ROS levels. Metabolic defects due to reduced Orsai (Osi) in time trigger defective food-seeking behavior and lethality. Further, we demonstrate that downregulation of Lipase 3, a fat body-specific lipase involved in lipid catabolism in response to starvation, rescues the reduced lipid droplet size associated with defective orsai. Finally, we show that osi-related phenotypes are rescued through the expression of its human ortholog ETFRF1/LYRm5, known to modulate the entry of ß-oxidation products into the electron transport chain; moreover, knocking down electron transport flavoproteins EtfQ0 and walrus/ETFA rescues osi-related phenotypes, further supporting this mode of action. CONCLUSIONS: These findings suggest that Osi may act in concert with the ETF complex to coordinate lipid homeostasis in the fat body in response to stage-specific demands, supporting cellular functions that in turn result in an adaptive behavioral response.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , Metabolismo de los Lípidos , Animales , Humanos , Adenosina Trifosfato/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Cuerpo Adiposo/metabolismo , Flavoproteínas/metabolismo , Larva , Lipasa/genética , Lipasa/metabolismo , Metabolismo de los Lípidos/genética , Lípidos , Especies Reactivas de Oxígeno/metabolismo
2.
Hautarzt ; 72(10): 855-859, 2021 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-33884438

RESUMEN

Tinea capitis is seen world-wide among children up to 12 years. The most severe type is Kerion Celsi with painful abscesses and lymphadenopathy. We report on an 11-year-old boy with Kerion Celsi, who was initially treated using antibiotics under the common misdiagnosis of a bacterial infection. Mycological investigations could identify Microsporum canis. The patient was treated orally with griseofulvin, which resulted in complete mycological remission after 8 weeks. Cicatrical alopecia, however, could not be prevented. Purulent infections of the scalp should lead to early mycological diagnostics in children.


Asunto(s)
Microsporum , Tiña del Cuero Cabelludo , Alopecia , Antifúngicos/uso terapéutico , Niño , Humanos , Masculino , Cuero Cabelludo , Tiña del Cuero Cabelludo/diagnóstico , Tiña del Cuero Cabelludo/tratamiento farmacológico
3.
Lett Appl Microbiol ; 71(5): 542-549, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32749003

RESUMEN

Malaria is a worldwide serious-threatening infectious disease caused by Plasmodium and the parasite resistance to antimalarial drugs has confirmed a significant obstacle to novel therapeutic antimalarial drugs. In this article, we assessed the antioxidant and anti-inflammatory activity of nanoparticles prepared from Indigofera oblongifolia extract (AgNPs) against the infection with Plasmodium chabaudi caused in mice spleen. AgNPs could significantly suppress the parasitaemia caused by the parasite to approximately 98% on day 7 postinfection with P. chabaudi and could improve the histopathological induced spleen damage. Also, AgNPs were able to increase the capsule thickness of the infected mice spleen. In addition, the AgNPs functioned as an antioxidant agent that affects the change in glutathione, nitric oxide and catalase levels in the spleen. Moreover spleen IL1ß, IL-6 and TNF-α-mRNA expression was regulated by AgNPs administration to the infected mice. These results indicated the anti-oxidant and the anti-inflammatory protective role of AgNPs against P. chabaudi-induced spleen injury.


Asunto(s)
Antioxidantes/farmacología , Indigofera/metabolismo , Malaria/tratamiento farmacológico , Extractos Vegetales/farmacología , Plasmodium chabaudi/efectos de los fármacos , Plata/farmacología , Animales , Catalasa/metabolismo , Glutatión/metabolismo , Interleucina-1beta/análisis , Interleucina-6/análisis , Malaria/parasitología , Malaria/patología , Masculino , Nanopartículas del Metal , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico/metabolismo , Parasitemia/tratamiento farmacológico , Parasitemia/patología , Bazo/parasitología , Factor de Necrosis Tumoral alfa/análisis
4.
Eur J Clin Microbiol Infect Dis ; 34(2): 367-83, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25224578

RESUMEN

This is the first multi-centre study regarding yeast infections in Romania. The aim was to determine the aetiological spectrum and susceptibility pattern to fluconazole, voriconazole and the novel compound MXP-4509. The 551 isolates were identified using routine laboratory methods, matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and DNA sequence analysis. Susceptibility testing was performed using the European Committee for Antimicrobial Susceptibility Testing (EUCAST) method and breakpoints. The yeasts originated from superficial infections (SUP, 51.5 %), bloodstream infections (BSI, 31.6 %) and deep-seated infections (DEEP, 16.9 %), from patients of all ages. Nine genera and 30 species were identified. The 20 Candida species accounted for 94.6 % of all isolates. C. albicans was the overall leading pathogen (50.5 %). Lodderomyces elongisporus is reported for the first time as a fungaemia cause in Europe. C. glabrata and Saccharomyces cerevisiae, as well as the non-Candida spp. and non-albicans Candida spp. groups, showed decreased fluconazole susceptibility (<75 %). The overall fluconazole resistance was 10.2 %. C. krusei accounted for 27 of the 56 fluconazole-resistant isolates. The overall voriconazole resistance was 2.5 % and was due mainly to C. glabrata and C. tropicalis isolates. Fluconazole resistance rates for the three categories of infection were similar to the overall value; voriconazole resistance rates differed: 4 % for BSI, 3.2 % for DEEP and 1.4 % for SUP. The antifungal activity of MXP-4509 was superior to voriconazole against C. glabrata and many fluconazole-resistant isolates. There was a large percentage of non-albicans Candida isolates. A large part of the high fluconazole resistance was not acquired but intrinsic, resulting from the high percentage of C. krusei.


Asunto(s)
Antifúngicos/farmacología , Micosis/epidemiología , Triazoles/farmacología , Levaduras/efectos de los fármacos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Candida/efectos de los fármacos , Candida/aislamiento & purificación , Niño , Preescolar , Farmacorresistencia Fúngica , Femenino , Fluconazol/farmacología , Fungemia , Humanos , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Micosis/microbiología , Rumanía/epidemiología , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/aislamiento & purificación , Voriconazol/farmacología , Levaduras/aislamiento & purificación , Adulto Joven
5.
Sci Total Environ ; 859(Pt 1): 160132, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36400291

RESUMEN

The present study employed data collected during the Mycosands survey to investigate the environmental factors influencing yeasts and molds distribution along European shores applying a species distribution modelling approach. Occurrence data were compared to climatic datasets (temperature, precipitation, and solar radiation), soil datasets (chemical and physical properties), and water datasets (temperature, salinity, and chlorophyll-a concentration) downloaded from web databases. Analyses were performed by MaxEnt software. Results suggested a different probability of distribution of yeasts and molds along European shores. Yeasts seem to tolerate low temperatures better during winter than molds and this reflects a higher suitability for the Northern European coasts. This difference is more evident considering suitability in waters. Both distributions of molds and yeasts are influenced by basic soil pH, probably because acidic soils are more favorable to bacterial growth. Soils with high nitrogen concentrations are not suitable for fungal growth, which, in contrast, are optimal for plant growth, favored by this environment. Finally, molds show affinity with soil rich in nickel and yeasts with soils rich in cadmium resulting in a distribution mainly at the mouths of European rivers or lagoons, where these metals accumulate in river sediments.


Asunto(s)
Ríos , Contaminantes del Suelo , Ríos/química , Suelo/química , Cadmio/análisis , Contaminantes del Suelo/análisis , Metales/análisis , Levaduras , Monitoreo del Ambiente
6.
Phys Rev E ; 105(1-1): 014202, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35193290

RESUMEN

Transmission measurements through three-port microwave graphs are performed, in analogy to three-terminal voltage drop devices with orthogonal, unitary, and symplectic symmetry. The terminal used as a probe is symmetrically located between two chaotic subgraphs, and each graph is connected to one port, the input and the output, respectively. The analysis of the experimental data clearly exhibits the weak localization and antilocalization phenomena. We find a good agreement with theoretical predictions, provided that the effects of dissipation and imperfect coupling to the ports are taken into account.

7.
Sci Total Environ ; 781: 146598, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-33812107

RESUMEN

The goal of most studies published on sand contaminants is to gather and discuss knowledge to avoid faecal contamination of water by run-offs and tide-retractions. Other life forms in the sand, however, are seldom studied but always pointed out as relevant. The Mycosands initiative was created to generate data on fungi in beach sands and waters, of both coastal and freshwater inland bathing sites. A team of medical mycologists and water quality specialists explored the sand culturable mycobiota of 91 bathing sites, and water of 67 of these, spanning from the Atlantic to the Eastern Mediterranean coasts, including the Italian lakes and the Adriatic, Baltic, and Black Seas. Sydney (Australia) was also included in the study. Thirteen countries took part in the initiative. The present study considered several fungal parameters (all fungi, several species of the genus Aspergillus and Candida and the genera themselves, plus other yeasts, allergenic fungi, dematiaceous fungi and dermatophytes). The study considered four variables that the team expected would influence the results of the analytical parameters, such as coast or inland location, urban and non-urban sites, period of the year, geographical proximity and type of sediment. The genera most frequently found were Aspergillus spp., Candida spp., Fusarium spp. and Cryptococcus spp. both in sand and in water. A site-blind median was found to be 89 Colony-Forming Units (CFU) of fungi per gram of sand in coastal and inland freshwaters, with variability between 0 and 6400 CFU/g. For freshwater sites, that number was 201.7 CFU/g (0, 6400 CFU/g (p = 0.01)) and for coastal sites was 76.7 CFU/g (0, 3497.5 CFU/g). For coastal waters and all waters, the median was 0 CFU/ml (0, 1592 CFU/ml) and for freshwaters 6.7 (0, 310.0) CFU/ml (p < 0.001). The results advocate that beaches should be monitored for fungi for safer use and better management.


Asunto(s)
Playas , Arena , Australia , Mar Negro , Hongos , Humanos , Italia , Microbiología del Agua
8.
Clin Microbiol Infect ; 26(11): 1464-1472, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32562861

RESUMEN

BACKGROUND: EUCAST has revised the definition of the susceptibility category I from 'Intermediate' to 'Susceptible, Increased exposure'. This implies that I can be used where the drug concentration at the site of infection is high, either because of dose escalation or through other means to ensure efficacy. Consequently, I is no longer used as a buffer zone to prevent technical factors from causing misclassifications and discrepancies in interpretations. Instead, an Area of Technical Uncertainty (ATU) has been introduced for MICs that cannot be categorized without additional information as a warning to the laboratory that decision on how to act has to be made. To implement these changes, the EUCAST-AFST (Subcommittee on Antifungal Susceptibility Testing) reviewed all, and revised some, clinical antifungal breakpoints. OBJECTIVES: The aim was to present an overview of the current antifungal breakpoints and supporting evidence behind the changes. SOURCES: This document is based on the ten recently updated EUCAST rationale documents, clinical breakpoint and breakpoint ECOFF documents. CONTENT: The following breakpoints (in mg/L) have been revised or established for Candida species: micafungin against C. albicans (ATU = 0.03); amphotericin B (S ≤/> R = 1/1), fluconazole (S ≤/> R = 2/4), itraconazole (S ≤/> R = 0.06/0.06), posaconazole (S ≤/> R = 0.06/0.06) and voriconazole (S ≤/> R = 0.06/0.25) against C. dubliniensis; fluconazole against C. glabrata (S ≤/> R = 0.001/16); and anidulafungin (S ≤/> R = 4/4) and micafungin (S ≤/> R = 2/2) against C. parapsilosis. For Aspergillus, new or revised breakpoints include itraconazole (ATU = 2) and isavuconazole against A. flavus (S ≤/> R = 1/2, ATU = 2); amphotericin B (S ≤/> R = 1/1), isavuconazole (S ≤ /> R = 1/2, ATU = 2), itraconazole (S ≤/> R = 1/1, ATU = 2), posaconazole (ATU = 0.25) and voriconazole (S ≤/> R = 1/1, ATU = 2) against A. fumigatus; itraconazole (S ≤/> R = 1/1, ATU = 2) and voriconazole (S ≤/> R = 1/1, ATU = 2) against A. nidulans; amphotericin B against A. niger (S ≤/> R = 1/1); and itraconazole (S ≤/> R = 1/1, ATU = 2) and posaconazole (ATU = 0.25) against A. terreus. IMPLICATIONS: EUCAST-AFST has released ten new documents summarizing existing and new breakpoints and MIC ranges for control strains. A failure to adopt the breakpoint changes may lead to misclassifications and suboptimal or inappropriate therapy of patients with fungal infections.


Asunto(s)
Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Candida/efectos de los fármacos , Anfotericina B/farmacología , Fluconazol/farmacología , Itraconazol/farmacología , Pruebas de Sensibilidad Microbiana , Guías de Práctica Clínica como Asunto , Triazoles/farmacología , Voriconazol/farmacología
9.
Science ; 233(4765): 734-9, 1986 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17835182

RESUMEN

Lack of solid data on rates of habitat conversion and on the basic biology of Neotropical organisms makes predictions of massive waves of extinction in South America premature. South America's problems regarding the use of natural resources are a result of historical, sociological, economic, and scientific factors. Most countries in South America have done a great deal to encourage conservation efforts, but the magnitude of the problem is well beyond their limited economic means to solve. The problems of species disappearance in South America are of global importance. A successful solution will involve a coordinated and massive effort of governments and specialists in all aspects of conservation biology from throughout the world. There is still time to resolve these problems. Unnecessarily dire predictions of species extinction may be counterproductive to the development of a long-term conservation strategy that is needed to manage Neotropical conservation problems.

10.
Science ; 255(5047): 976-9, 1992 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-17793161

RESUMEN

Data were compiled on the distribution of mammal taxa (883 species, 242 genera, 45 families, and 10 orders) among South America's six major macrohabitats: lowland Amazon forest, western montane forests, Atlantic rain forest, upland semideciduous forest, southern mesophytic forest, and drylands. The drylands are the richest area in numbers of species supported and are more diverse than the other habitats, including the lowland Amazon rain forest, when endemics are considered. An analysis of number of endemic and nonendemic taxa versus size of area found a simple positive linear relationship: the drylands, almost twice as extensive as the Amazon lowlands, support more endemic taxa. Conservation plans that emphasize the wet tropics and fail to consider the drylands as special repositories of mammal diversity will be unable to preserve a significant number of novel taxa.

11.
Roum Arch Microbiol Immunol ; 68(3): 171-4, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20361538

RESUMEN

SCOPE: Genital infections represent one of the most important causes of infertility, affecting: fallopian tubes, endometrial mucosa, sperm parameters. The aim of this study is to evaluate the involvement of four sexually transmitted infections (STD) in the achievement of infertility and to establish the prevalence of each infectious agent in our patients. METHODS: We analyzed the presence of Chlamydia trachomatis (CT) antigen, Ureaplasma urealyticum (UU), Mycoplasma hominis (MH) and Neisseria gonorrhoeae (NG) in the endocervical secretions and Chlamydia trachomatis antibodies IgA, IgG, IgM in the serum of 125 infertile women as well as in 30 pregnant women in the 3rd trimester of pregnancy, as a control group. RESULTS. In infertile women, the prevalence rate of the four bacterial markers was: CT antigen 1/125 (0.80%), CT IgG antibodies 19/125 (15.20%), MH 6/125 (4.80%), UU 51/125 (40.80%) and NG 1/125 (0.8%). From the control group, none was positive for CT antigen, but 1/30 (3.33% of patients) was positive for CT IgA while the prevalence rate for MH and UU were 16.66% and 43.33% respectively. CONCLUSIONS: We couldn't prove any association between genital MH/UU and infertility as the prevalence was higher in the control group than in the cases, but the correlation of the CT infection with the infertility was clearly shown. However, it is necessary to perform routine tests to screen for CT, NG, UU and MH among infertile patients. The positivity for CT IgG is a marker better correlated with fallopian tube obstruction than the CT antigen.


Asunto(s)
Infecciones Bacterianas/epidemiología , Infertilidad Femenina/epidemiología , Infertilidad Femenina/microbiología , Adulto , Infecciones Bacterianas/microbiología , Femenino , Humanos , Rumanía/epidemiología , Estudios Seroepidemiológicos
12.
Phys Rev E ; 99(6-1): 062202, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31330740

RESUMEN

We study the voltage drop along three-terminal disordered wires in all transport regimes, from the ballistic to the localized regime. This is performed by measuring the voltage drop on one side of a one-dimensional disordered wire in a three-terminal setup as a function of disorder. Two models of disorder in the wire are considered: (i) the one-dimensional Anderson model with diagonal disorder and (ii) finite-width bulk-disordered waveguides. Based on the known ß dependence of the voltage drop distribution of the three-terminal chaotic case, ß being the Dyson symmetry index (ß=1, 2, and 4 for orthogonal, unitary, and symplectic symmetries, respectively), the analysis is extended to a continuous parameter ß>0 and uses the corresponding expression as a phenomenological one to reach the disordered phase. We show that our proposal encompasses all the transport regimes with ß depending linearly on the disorder strength.

13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 78(3 Pt 2): 036208, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18851122

RESUMEN

We derive an exact formula to calculate the absorption strength in absorbing chaotic systems such as microwave cavities or acoustic resonators. The formula allows us to estimate the absorption strength as a function of the averaged reflection coefficient and the real coupling parameter. We also define the weak and strong absorption regimes in terms of the coupling parameter and the absorption strength.

14.
Sci Rep ; 6: 25157, 2016 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-27121226

RESUMEN

Coherent transport phenomena are difficult to observe due to several sources of decoherence. For instance, in the electronic transport through quantum devices the thermal smearing and dephasing, the latter induced by inelastic scattering by phonons or impurities, destroy phase coherence. In other wave systems, the temperature and dephasing may not destroy the coherence and can then be used to observe the underlying wave behaviour of the coherent phenomena. Here, we observe coherent transmission of mechanical waves through a two-dimensional elastic Sinai billiard with two waveguides. The flexural-wave transmission, performed by non-contact means, shows the quantization when a new mode becomes open. These measurements agree with the theoretical predictions of the simplest model highlighting the universal character of the transmission fluctuations.

15.
J Mol Biol ; 218(1): 21-2, 1991 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-2002505

RESUMEN

Single crystals of the glycosylated inhibitor of cathepsin D and trypsin isolated from potato tubers were obtained using the hanging drop vapor diffusion method and ammonium nitrate as precipitant. The crystals exhibit strong F222 pseudo symmetry but belong to the orthorhombic space group C222 or C222(1), with cell parameters a = 73.8 A, b = 119.9 A and c = 133.2 A with two molecules per asymmetric unit. The crystals diffract to a resolution of 2.4 A.


Asunto(s)
Catepsina D/antagonistas & inhibidores , Proteínas de Plantas , Proteínas/química , Solanum tuberosum , Cristalización , Liofilización , Conformación Proteica , Proteínas/aislamiento & purificación , Difracción de Rayos X
16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(3 Pt 2): 036202, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16241543

RESUMEN

Motivated by recent theoretical and experimental works, we study the statistical fluctuations of the parametric derivative of the transmission T and reflection R coefficients, T/deltaX and R/deltaX, respectively, in ballistic chaotic cavities in the presence of absorption. Analytical results for the variance of T/deltaX and R/deltaX, with and without time-reversal symmetry, are obtained for asymmetric and left-right symmetric cavities. These results are valid for an arbitrary number of channels for strong absorption strength, in complete agreement with the results found in the literature in the absence of absorption. A simple extrapolation to any absorption strength is qualitatively correct.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(2 Pt 2): 026224, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16196701

RESUMEN

We propose a model to describe the statistical properties of wave scattering through a classically chaotic cavity in the presence of surface absorption. Experimentally, surface absorption could be realized by attaching an "absorbing patch" to the inner wall of the cavity. In our model, the cavity is connected to the outside by a waveguide with N open modes (or channels), while an experimental patch is simulated by an "absorbing mirror" attached to the inside wall of the cavity; the mirror, consisting of a waveguide that supports N(a) channels, with absorption inside and a perfectly reflecting wall at its end, is described by a subunitary scattering matrix S(a). The number of channels N(a) , as a measure of the geometric cross section of the mirror, and the lack of unitarity P(a) = [symbol: see text]N(a) - S(a)(+)S(a) , as a measure of absorption, are under our control: these parameters have an important physical significance for real experiments. The absorption strength in the cavity is quantified by gamma(a) = tr P(a). The statistical distribution of the resulting S matrix for N = 1 open channel and only one absorbing channel, N(a) = 1, is solved analytically for the orthogonal and unitary universality classes, beta = 1 and beta = 2, respectively, and the results are compared with those arising from numerical simulations. The relation with other models existing in the literature, in some of which absorption has a volumetric character, is also studied.

18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(3 Pt 2A): 036201, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15903540

RESUMEN

We study the effect of left-right symmetry on the distribution of the parametric derivative of the dimensionless conductance T with respect to an external parameter X , partial differentialT/ partial differentialX , of ballistic chaotic cavities with two leads, each supporting N propagating modes. We show that T and partial differentialT/ partial differentialX are linearly uncorrelated for any N . For N=1 we calculate the distribution of partial differentialT/ partial differentialX in the presence and absence of time-reversal invariance. In both cases, it has a logarithmic singularity at zero derivative and algebraic tails with an exponent different from the one of the asymmetric case. We also obtain explicit analytical results for the mean and variance of the distribution of partial differentialT/ partial differentialX for arbitrary N . Numerical simulations are performed for N=5 and 10 to show that the distribution P ( partial differentialT/ partial differentialX) tends towards a Gaussian one when N increases.

19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(1 Pt 2): 016223, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15697714

RESUMEN

We measure the transmission through asymmetric and reflection-symmetric chaotic microwave cavities in dependence on the number of attached waveguides. Ferrite cylinders are placed inside the cavities to break time-reversal symmetry. The phase-breaking properties of the ferrite and its range of applicability are discussed in detail. We use the random matrix theory accounting for absorption effects to calculate the universal distribution of transmission coefficients T and their energy derivatives dT/depsilon. Using the absorption strength as a fitting parameter, we find good agreement between universal transmission fluctuations predicted by the theory and the experimental data.

20.
Food Chem Toxicol ; 85: 2-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26260749

RESUMEN

Lupeol exhibits anti-inflammatory effects; unfortunately it shows low water solubility. An alternative to overcome this is the development of nanomaterials. Several methods for nanomaterial production are available. One of them is emulsification/solvent-evaporation. The objective of the present work was to evaluate physical properties, transport and in vitro modulator effects on NF-κB of poly (lactide-co-glycolide) (PLGA) nanoparticles loaded with lupeol. Nanonutraceuticals were prepared with 16% (w/v) of lupeol. Size distribution and morphology were measured by particle size analyzer and TEM. In vitro release of lupeol was studied by three different models: Higuchi, Siepmann & Peppas, and Power law. Transport of nanonutraceutical was studied in a Caco-2 cell model and by GC-MS. Modulator effect on NK-κB was studied by western blot analysis. Nanonutraceuticals were 10% larger than the nanoparticles without lupeol (372 vs 337 nm) and presented a broader size distribution (0.28 vs 0.22). TEM results displayed spherical structures with a broader size distribution. Entrapment efficiency of lupeol was 64.54% and it in vitro release data fitted well to the Power law and Higuchi equation (R > 0.84-0.84). Strong regulation of NF-κB of nanonutraceutical was observed. It was not observed any transport across the Caco-2 cell model at the different experimental conditions.


Asunto(s)
Antiinflamatorios no Esteroideos/metabolismo , Enterocitos/metabolismo , Absorción Intestinal , FN-kappa B/metabolismo , Nanopartículas/efectos adversos , Triterpenos Pentacíclicos/metabolismo , Poliglactina 910/efectos adversos , Transporte Activo de Núcleo Celular , Algoritmos , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/análisis , Antiinflamatorios no Esteroideos/química , Células CACO-2 , Permeabilidad de la Membrana Celular , Supervivencia Celular , Fenómenos Químicos , Suplementos Dietéticos/análisis , Emulsiones , Humanos , Microscopía Electrónica de Transmisión , FN-kappa B/agonistas , FN-kappa B/antagonistas & inhibidores , Nanopartículas/química , Nanopartículas/ultraestructura , Tamaño de la Partícula , Triterpenos Pentacíclicos/administración & dosificación , Triterpenos Pentacíclicos/análisis , Triterpenos Pentacíclicos/química , Poliglactina 910/química , Polivinilos/química , Solubilidad , Tensoactivos/química
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