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The objective of the present study was to investigate the effect of the whey on broiler chicks' performance, welfare, and caecal Campylobacter counts under experimental and field conditions. In the experimental study, 120-d-old broiler chicks were randomly allocated to four treatment groups, as described below: group A, which served as negative control; group B, fed with a diet supplemented with 1% whey; group C, challenged with Campylobacter jejuni; and group D, supplemented with 1% whey and challenged with C. jejuni, respectively. Performance indexes and caecal C. jejuni counts were calculated. In addition to the performance indexes, the hock burn and the foot pad dermatitis lesions score were measured to assess the welfare status of broiler chicks. In order to evaluate the use of whey under field conditions, a second study was performed in a broiler farm with two identical houses. The evaluation of the experimental data revealed that the use of whey did not affect significantly the performance (P ≤ 0.05) and the caecal C. jejuni counts (P ≤ 0.05). There were neither footpad dermatitis lesions nor hock burn lesions in any of the experimental groups. In the field study, the use of whey had no effect on the performance indexes (P ≤ 0.05). It can be concluded that the addition of whey has no negative effect on poultry and may provide an alternative natural feed additive for the broiler feed industry.
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Infecciones por Campylobacter/veterinaria , Campylobacter jejuni/aislamiento & purificación , Dieta/veterinaria , Suero Lácteo/administración & dosificación , Alimentación Animal/análisis , Animales , Infecciones por Campylobacter/microbiología , Ciego/microbiología , Pollos/crecimiento & desarrollo , Pollos/microbiología , Enfermedades de las Aves de Corral/microbiología , Suero Lácteo/efectos adversosRESUMEN
Superparamagnetic iron oxide (Fe3O4) and highly anisotropic barium hexaferrite (BaFe12O19) nanoparticles were coated with an anti-inflammatory drug and magnetically transported through mucus produced by primary human airway epithelial cells. Using wet planetary ball milling, dl-2-amino-3-phosphonopropionic acid-coated BaFe12O19 nano-particles (BaNPs) of 1-100 nm in diameter were prepared in water. BaNPs and conventional 20-30-nm Fe3O4 nanoparticles (FeNPs) were then encased in a polymer (PLGA) loaded with dexamethasone (Dex) and tagged for imaging. PLGA-Dex-coated BaNPs and FeNPs were characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), and superconducting quantum interference device (SQUID) magnetometry. Both PLGA-Dex-coated BaNPs and FeNPs were transferred to the surface of a ~100-µm thick mucus layer of air-liquid interface cultured primary normal human tracheobronchial epithelial (NHTE) cells. Within 30 min, the nanoparticles were pulled successfully through the mucus layer by a permanent neodymium magnet. The penetration time of the nanomedicine was monitored using confocal microscopy and tailored by varying the thickness of the PLGA-Dex coating around the particles.
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It is illustrated and computationally verified by ab initio density functional theory and simple but powerful order-of-magnitude arguments, based on deformation energy ΔEdef in relation to the uncertainty principle, that the conductivity and aromaticity of graphene and graphene-based structures, such as graphene dots, antidots, and nanoribbons, are negatively interrelated for π aromatic structures, in agreement with recent experimental data. However, for σ aromaticity, the interrelation could be positive, especially for extended periodic structures. We predict that the conductivity of rectangular graphene dots and antidots, is anisotropic with much larger magnitude along the direction perpendicular to the zigzag edges, compared to the conductivity in direction parallel to them. The same is true for the polarizability and electron mobility. This is directly connected with the much higher aromaticity around the armchair edges compared to the aromaticity near the zigzag edges. Furthermore, contrary to what would be expected on the basis of simple arguments for defect states, we predict that antidot patterning could significantly improve the conductivity (sometimes by 1 order of magnitude) in one or both directions, depending on their number, arrangement, and passivation. For narrow atomically precise armchair nanoribbons (AGNRs) of finite length, both conductivity and energy gaps are dominated by lateral and longitudinal quantum confinement, which decrease with increasing length (for a given width), leading to a peculiar behavior of monotonically increasing "maximum conductivity" as the band gaps monotonically decrease. The electron distribution at the band edges of the AGNRs, in agreement with recent experimental data are well-localized at the zigzag edges. Using the concept of gap-determining LUMO-HOMO frontier states to avoid HOMOs and LUMOs localized at the zigzag edges, we can predict with very high accuracy the recently measured band gaps of AGNRs of widths N = 7 and N = 13. Both the smallest (10-3-10-4[Formula: see text]) and the largest (a few 2[Formula: see text]) calculated values of conductance and conductivity for the smaller structures and the larger nanographenes, respectively, are in full accord with the corresponding experimental values of single-molecule junction conductance and the measured minimum conductivity of graphene at 1.6 K.
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Thrombophilic genetic factors have been shown to play an important role in implantation outcome after in vitro fertilisation (IVF). In this pilot study we investigated the frequencies of glycoprotein Ia (GpIa)-C807T and GpIIIa-PlA1/PlA2 polymorphisms in 60 nulligravidae women with a history of unexplained IVF implantation failures and compared them with 60 healthy fertile women. We found statistically significant associations between the GpIa-C807T and GpIIIa-PlA1/PlA2 polymorphisms and IVF implantation failure (odds ratio [OR] = 3.45, 95% confidence interval [CI]: 1.63-7.30, p = 0.001; and OR = 2.86, 95% CI: 1.27-6.45, p = 0.010, respectively) with the risk being higher for combined carriers of GpIa-807T and GpIIIa-PlA2 alleles (OR = 10.13, 95% CI: 2.85-35.99, p < 0.001), suggesting a synergistic effect of the two polymorphisms. The above associations were strongest for the youngest age group. Our results indicate that GpIa-807T and GpIIIa-PlA2 may be susceptibility alleles for IVF implantation failure.
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Implantación del Embrión/genética , Integrina alfa2/genética , Integrina beta3/genética , Adulto , Anciano , Alelos , Estudios de Casos y Controles , Femenino , Fertilización In Vitro , Humanos , Persona de Mediana Edad , Proyectos Piloto , Polimorfismo de Nucleótido Simple , Insuficiencia del TratamientoRESUMEN
Switchable and tunable chiral metamaterial response is numerically demonstrated here in different uniaxial chiral metamaterial structures operating in the THz regime. The structures are based on the bi-layer conductor design and the tunable/switchable response is achieved by replacing parts of the metallic components of the structures by photoconducting Si, which can be transformed from an insulating to an almost conducting state through photoexcitation, achievable under external optical pumping. All the structures proposed and discussed here exhibit frequency regions with giant tunable circular dichroism, as well as regions with giant tunable optical activity, showing unique potential in the achievement of active THz polarization components, like tunable polarizers and polarization filters.
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Anorexia nervosa is a serious eating disorder that is associated with decreased bone mineral density and greater lifetime risk for fractures. This case-controlled study, analyzed single nucleotide polymorphisms of genes encoding vitamin D receptor, estrogen receptor alpha (ESR1), collagen type I and calcitonin receptor (CTR). Relationships between genotype and body mass index, cycling status and lumbar spine bone mineral density (LBMD) were determined in 40 adolescent girls with anorexia nervosa and 10 age-matched controls. The distribution of CTR-AluI genotypes differed between groups, but this polymorphism was not associated with LBMD Z-score. Distribution of ESR1-XbaI genotypes did not differ between groups, but the AA genotype was associated with decreased LBMD Z-score (≤-1) (OR = 24.79, 95% CI, 1.01-606.08). Carriers of the A allele were more likely to have decreased LBMD Z-scores compared with carriers of the G allele (OR = 4.12, 95% CI, 1.23-13.85, p = 0.022). In conclusion, our study shows that anorexic patients with wild-type genotype ESR-XbaI receptor are in greater risk for decreased BMD in relation to those with the mutated gene. Prompt recognition of these patients is crucial because early administration of the proper therapeutic treatment may contribute to the prevention of adverse sequelae on bone metabolism.
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Anorexia Nerviosa/genética , Densidad Ósea/genética , Receptor alfa de Estrógeno/genética , Osteoporosis/genética , Receptores de Calcitonina/genética , Receptores de Calcitriol/genética , Receptores de Colágeno/genética , Adolescente , Anorexia Nerviosa/complicaciones , Estudios de Casos y Controles , Niño , Femenino , Predisposición Genética a la Enfermedad , Humanos , Integrina alfa2beta1 , Región Lumbosacra , Osteoporosis/complicaciones , Proyectos Piloto , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Adulto JovenRESUMEN
We present and analyze the unique phenomena of enhanced THz transmission through a subwavelength LiF dielectric rod lattice embedded in an epsilon-near-zero KCl host. Our experimental results in combination with theoretical calculations show that subwavelength waveguiding of terahertz radiation is achieved within an alkali-halide eutectic metamaterial as result of the coupling of Mie-resonance modes arising in the dielectric lattice.
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In this paper we discuss the fabrication and the electromagnetic (EM) characterization of anisotropic eutectic metamaterials, consisting of cylindrical polaritonic LiF rods embedded in either KCl or NaCl polaritonic host. The fabrication was performed using the eutectics directional solidification self-organization approach. For the EM characterization the specular reflectance at far infrared, between 3 THz and 11 THz, was measured and also calculated by numerically solving Maxwell equations, obtaining good agreement between experimental and calculated spectra. Applying an effective medium approach to describe the response of our samples, we predicted a range of frequencies in which most of our systems behave as homogeneous anisotropic media with a hyperbolic dispersion relation, opening thus possibilities for using them in negative refractive index and imaging applications at THz range.
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Metales/química , Modelos Químicos , Modelos Moleculares , Simulación por Computador , Luz , Dispersión de Radiación , Radiación TerahertzRESUMEN
AIM: The multifactorial pathway leading to preterm labor possibly includes the implication of apoptosis. This study aimed to clarify the role of amniotic fluid apoptotic molecules (TNF-alpha, cytochrome C and cell death nucleosomes) at midtrimester as possible predictors of preterm labor (PTL) and/or premature rupture of membranes (PROM). METHOD: In this case-control study, comprising 360 women undergoing genetic amniocentesis and out of whom 38 delivered preterm and 18 out of the latter after PROM, the above apoptotic molecules were determined by ELISA. The 38 cases with PTL and 18 cases with PROM were matched for age with 38 and 18 respective controls delivering at term, and the levels of apoptotic molecules were compared. RESULTS: Cell death nucleosome levels were found to be significantly associated with preterm delivery. Specifically, for every unit increase in nucleosomes, women were on average 0.2% more likely to deliver preterm (OR: 1.002, CI: 1.0-1.003, p = 0.018). In contrast, such an association was not found concerning the other two apoptotic molecules (TNF-a and Cytochrome C). CONCLUSION: Second-trimester amniotic fluid cell death nucleosomes' levels are significantly associated with preterm delivery and could possibly serve as predicting markers.
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Líquido Amniótico/metabolismo , Citocromos c/metabolismo , Rotura Prematura de Membranas Fetales/diagnóstico , Nucleosomas/metabolismo , Trabajo de Parto Prematuro/diagnóstico , Factor de Necrosis Tumoral alfa/metabolismo , Adulto , Líquido Amniótico/química , Biomarcadores/análisis , Biomarcadores/metabolismo , Estudios de Casos y Controles , Muerte Celular , Citocromos c/análisis , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Segundo Trimestre del Embarazo , Factor de Necrosis Tumoral alfa/análisisRESUMEN
AIM: Strong evidence implicates chronic intraamniotic inflammation in the etiology of preterm delivery. The purpose of this study was to determine whether amniotic fluid IL-1ß, IL-10 and IL-18 concentrations in women undergoing mid-trimester amniocentesis can identify those at risk for preterm labor or preterm rupture of membranes. PATIENTS AND METHODS: A case-control study was conducted to compare mid-trimester concentrations of amniotic fluid IL-1ß, IL-10 and IL-18 in women delivering at term or preterm. Out of 362 women included in the study, 38 presented with preterm labor. Thirty-eight women with term delivery, matched for chronological and gestational age served as controls. Women with abnormal fetal karyotypes or major anomalies were excluded. IL-1ß, IL-10 and IL-18 concentrations were determined by ELISA. Conditional logistic regression was applied in the statistical analysis. RESULTS: IL-1ß was found to be positively and significantly associated with preterm delivery. Specifically, for every unit increase in IL-1ß, women were on average 7.2 (OR: 7.2, CI: 1.94-26.77, p=0.003) times more likely to deliver preterm. IL-18 levels as well as gender were significantly associated with preterm delivery. Specifically, for every unit increase in IL-18, women were on average 1% less likely to have a preterm delivery (OR: 0.99, CI: 0.98-0.99, p=0.04). On the other hand, IL-10 was not significantly associated with preterm delivery. CONCLUSION: Mid-trimester IL-1ß concentrations are positively associated with preterm delivery. Therefore, IL-1ß, determined on the occasion of mid-trimester amniocentesis could possibly serve as a marker of preterm delivery. In contrast, IL-10 and IL-18 concentrations are not elevated in mid-trimester amniotic fluid and probably cannot serve this purpose.
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Líquido Amniótico/inmunología , Interleucina-10/análisis , Interleucina-18/análisis , Interleucina-1beta/análisis , Trabajo de Parto Prematuro/diagnóstico , Segundo Trimestre del Embarazo/inmunología , Adulto , Amniocentesis , Biomarcadores/análisis , Femenino , Humanos , Interleucina-10/inmunología , Interleucina-18/inmunología , Interleucina-1beta/inmunología , Modelos Logísticos , Trabajo de Parto Prematuro/inmunología , EmbarazoRESUMEN
AIM: To evaluate maternal TNF-alpha and IL-6 plasma levels in normotensive pregnant women, women with preeclampsia, and to examine the temporal changes in their levels from the antepartum to the postpartum period correlated with the regression of preeclampsia. METHOD: A prospective study was performed in the 2nd Department of Obstetrics and Gynecology, University of Athens. Blood samples were obtained: (1) antepartum at the time of clinical diagnosis of the syndrome, 2. 12-14 weeks postpartum. RESULTS: No statistically significant differences were found in IL-6 levels, whereas a difference was found in TNF-alpha levels between preeclamptic and controls in antepartum period (0.80 pg/ml versus 0.60 pg/ml, P : .04). Long after delivery, TNF-alpha levels were significantly higher in preeclamptic compared to normotensive controls (0.86 pg/ml versus 0.60 pg/ml, P : .004). No difference was observed in TNF-alpha before and after delivery in both groups. No difference was noticed in IL-6 levels in women of normotensive group long after delivery compared to that before delivery. Long after delivery IL-6 levels were statistically significant higher in preeclamptic women compared to normal controls (3.53 ± 0.52 pg/ml versus 1.69 ± 0.48 pg/ml, P : .02). CONCLUSION: Preeclamptic women remain under a status of increased inflammatory stress up to 12-14 weeks postpartum despite the fact that all the other signs of preeclampsia are resolved.
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Regulación de la Expresión Génica , Interleucina-6/sangre , Preeclampsia/sangre , Factor de Necrosis Tumoral alfa/sangre , Adulto , Presión Sanguínea , Femenino , Humanos , Hipertensión/sangre , Inflamación , Periodo Posparto/sangre , Embarazo , Estudios Prospectivos , Factores de TiempoRESUMEN
We demonstrate theoretically that one can obtain repulsive Casimir forces and stable nanolevitations by using chiral metamaterials. By extending the Lifshitz theory to treat chiral metamaterials, we find that a repulsive force and a minimum of the interaction energy possibly exist for strong chirality, under realistic frequency dependencies and correct limiting values (for zero and infinite frequencies) of the permittivity, permeability, and chiral coefficients.
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We present a planar design of a metamaterial exhibiting electromagnetically induced transparency that is amenable to experimental verification in the microwave frequency band. The design is based on the coupling of a split-ring resonator with a cut-wire in the same plane. We investigate the sensitivity of the parameters of the transmission window on the coupling strength and on the circuit elements of the individual resonators, and we interpret the results in terms of two linearly coupled Lorentzian resonators. Our metamaterial designs combine low losses with the extremely small group velocity associated with the resonant response in the transmission window, rendering them suitable for slow light applications at room temperature.
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Materiales Manufacturados/efectos de la radiación , Modelos Teóricos , Refractometría/métodos , Simulación por Computador , Campos Electromagnéticos , MicroondasRESUMEN
We demonstrate theoretically that electromagnetically induced transparency can be achieved in metamaterials, in which electromagnetic radiation is interacting resonantly with mesoscopic oscillators rather than with atoms. We describe novel metamaterial designs that can support a full dark resonant state upon interaction with an electromagnetic beam and we present results of its frequency-dependent effective permeability and permittivity. These results, showing a transparency window with extremely low absorption and strong dispersion, are confirmed by accurate simulations of the electromagnetic field propagation in the metamaterial.
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We present a systematic numerical study, validated by accompanied experimental data, of individual and coupled split ring resonators (SRRs) of a single rectangular ring with one, two and four gaps. We discuss the behavior of the magnetic resonance frequency, the magnetic field and the currents in the SRRs, as one goes from a single SRR to strongly interacting SRR pairs in the SRR plane. We show that coupling of the SRRs along the E direction results to shift of the magnetic resonance frequency to lower or higher values, depending on the capacitive or inductive nature of the coupling. Strong SRR coupling along propagation direction usually results to splitting of the single SRR resonance into two distinct resonances, associated with peculiar field and current distributions.
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Using transmission and reflection measurements under normal incidence in one and three layers of a mum-scale metamaterial consisting of pairs of short-slabs and continuous wires, fabricated by a photolithography procedure, we demonstrate the occurrence of a negative refractive index regime in the far infrared range, ~2.4-3 THz. The negative index behavior in that system at ~2.4-3 THz is further confirmed by associated simulations, which are in qualitative agreement with the experimental results.
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Modelos Teóricos , Refractometría/instrumentación , Refractometría/métodos , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Rayos Infrarrojos , Luz , Miniaturización , Dispersión de RadiaciónRESUMEN
OBJECTIVE: Estrogen agonist compounds may exert cardioprotective activity by modulating adipocytokine concentration and apoptosis. The objective of this study was to evaluate the effects of hormone therapy, tibolone and raloxifene on the serum adipocytokines resistin and adiponectin as well as on circulating markers of receptor-mediated apoptosis. Design Randomized, open-label, intervention study in the Menopause Clinic of a University Hospital. METHODS: One hundred healthy postmenopausal women were randomized to the following groups: conjugated equine estrogens 0.625 mg (CEE) (n = 16); 17 beta-estradiol 1 mg plus norethisterone acetate 0.5 mg (E(2)/NETA) (n = 15); tibolone 2.5 mg (n = 18); raloxifene HCl 60 mg (n = 20); and no treatment (n = 19). Eighty-eight women completed the 3-month study period. Main outcome measures were levels of serum adiponectin, resistin, soluble Fas and Fas ligand. RESULTS: Levels of serum adiponectin decreased significantly in the tibolone group (baseline: 10 556.7 +/- 4213.5 ng/ml; 3 months: 7856.3 +/- 3450.7 ng/ml; p = 0.0001) and increased in the CEE group (baseline: 9268.1 +/- 5158 ng/ml; 3 months: 11 302.6 +/- 4980.9 ng/ml; p = 0.01). Serum resistin values increased only in the tibolone group (baseline: 2.81 +/- 0.89 ng/ml; 3 months: 3.55 +/- 1.31 ng/ml; p = 0.04), while the level of Fas ligand decreased significantly in the E2/NETA (baseline: 70.4 +/- 21.9 pg/ml; 3 months: 62.1 +/- 18.6 pg/ml; p = 0.02) and tibolone group (baseline: 68.2 +/- 25.7 pg/ml; 3 months: 59.2 +/- 21.7 pg/ml; p = 0.01). CONCLUSIONS: Of the regimens investigated, only unopposed estrogens may exert an atheroprotective effect through the increase of adiponectin and a resultant favorable lipid and anti-inflammatory profile.
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Adiponectina/sangre , Apoptosis/efectos de los fármacos , Aterosclerosis/prevención & control , Terapia de Reemplazo de Estrógeno/métodos , Lípidos/sangre , Resistina/sangre , Adipoquinas/sangre , Adulto , Aterosclerosis/sangre , Estrógenos Conjugados (USP)/farmacología , Proteína Ligando Fas/sangre , Femenino , Grecia , Humanos , Acetato de Medroxiprogesterona/farmacología , Persona de Mediana Edad , Norpregnenos/farmacología , Posmenopausia , Clorhidrato de Raloxifeno/farmacología , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Receptor fas/sangreRESUMEN
Neurotrophins (NTs), nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), NT-3, and NT-4 are of major importance in prenatal and postnatal brain development, due to their neuroprotective action. Developmental changes alter the neuronal responsiveness to certain NTs, which subsequently are variously expressed, to properly balance their action. The following study aimed at examining the pattern of perinatal changes of the four NTs--NGF, BDNF, NT-3, and NT-4 in 30 appropriate for gestational age (AGA) full-term fetuses and neonates by determining their circulating levels at characteristic time points. This study show a gradual decrease of circulating levels of the NTs, NT-3 and NT-4 from umbilical cord (UC) to neonates day 4 (N4), while circulating levels of NGF and BDNF present the opposite pattern: an increase from UC to N4. These patterns of perinatal changes differ according to their impact on the process of neuronal development and their reaction to perinatal stress. NT3 and NT4 have been documented to act at early stages of neuronal development and to decrease after hypoxia-ischemia, while NGF and BDNF to increase. Further studies should investigate these patterns in premature or full-term infants, presenting various pathological conditions in the perinatal period.
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Recién Nacido/sangre , Factores de Crecimiento Nervioso/sangre , Adulto , Factor Neurotrófico Derivado del Encéfalo/sangre , Femenino , Sangre Fetal/química , Edad Gestacional , Humanos , Neurotrofina 3/sangre , EmbarazoRESUMEN
We investigate numerically the limits of the resonant magnetic response with a negative effective permeability mu(eff) for single-ring multicut split-ring resonator (SRR) designs up to optical frequencies. We find the breakdown of linear scaling due to the free electron kinetic energy for frequencies above approximately 100 THz. Above the linear scaling regime, the resonance frequency saturates, while the amplitude of the resonant permeability decreases, ultimately ceasing to reach negative value. The highest resonance frequency at which mu(eff) < 0 increases with the number of cuts in the SRR. A LC circuit model provides explanation of the numerical data.