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1.
Phys Chem Chem Phys ; 24(2): 1023-1028, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34927637

RESUMO

A large variety of recently predicted and synthesized 2D materials significantly broaden the capabilities of magnetic interface design for spintronic applications. Their diverse structural and electronic properties allow fine adjustment of interfacial interactions between the electrode and spacer materials providing robust and effective spin transport. Based on recent experimental results, here we present a theoretical study of novel interfaces formed by a half-metallic Co2FeGe1/2Ga1/2 (CFGG) substrate with h-BN or MoSe2 monolayer on its top. By means of the DFT approach, the structural, magnetic and electronic properties are studied for the Co- and FeGeGa termination of the CFGG surface. The observed large spin polarization in the vicinity of the interface and robust magnetization exhibit the potential of 2D materials/CFGG heterostructures for spintronic applications.

2.
Arch. Soc. Esp. Oftalmol ; 96(12): 668-672, dic. 2021. ilus
Artigo em Espanhol | IBECS | ID: ibc-218365

RESUMO

Caso clínico Varón de 58 años que acude derivado a consultas de sección retina por pérdida de agudeza visual (AV) en el ojo izquierdo (OI). En la primera visita, la AV fue de 0,9 en el ojo derecho (OD) y movimiento de manos en OI y la presión intraocular (PIO) fue de 34 mmHg y 42 mmHg en ojo derecho e izquierdo, respectivamente. En la fundoscopia se observó aumento de la excavación del nervio óptico y palidez papilar en ambos ojos y edema del polo posterior en OI. La tomografía de coherencia óptica (OCT) y la angiografía fluoresceínica confirmaron el diagnóstico de desprendimiento de retina (DR) seroso macular causado por foseta papilar secundaria a glaucoma. El tratamiento quirúrgico combinado mediante implante de dispositivo de drenaje ExPress, vitrectomía pars plana (VPP) y endofotocoagulación láser yuxtapapilar logró la normalización de la PIO y la resolución anatómica completa del DR macular (AU)


Case report A 58-year-old man was referred to the retina specialist for evaluation of decreased vision in the left eye (LE). At the first visit, visual acuity was 0.9 in right eye (RE) and hands movement in LE, and the intraocular pressure (IOP) was 34 mmHg and 42 mmHg in right and left eye, respectively. Dilated funduscopic examination revealed papillary pallor, increased cup-to-disc ratio of the optic nerve in both eyes, and retinal posterior pole edema in the LE. Optical coherence tomography (OCT) and fluorescein angiography assessment confirmed the diagnosis of a macular serous retinal detachment (RD) caused by an optic disc pit secondary to glaucoma. Combined surgical treatment with ExPress drainage device implantation, pars plana vitrectomy (PPV), and juxtapapillar laser endophotocoagulation was performed. IOP normalization was achieved as well as complete anatomical resolution of macular RD (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Glaucoma/complicações , Degeneração Macular/etiologia , Degeneração Macular/cirurgia , Terapia Combinada , Cirurgia Filtrante , Vitrectomia , Fotocoagulação a Laser , Resultado do Tratamento
3.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(12): 668-672, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34844689

RESUMO

CASE REPORT: A 58-year-old man was referred to the retina specialist for evaluation of decreased vision in the left eye (LE). At the first visit, visual acuity was 0.9 in right eye (RE) and hands movement in LE, and the intraocular pressure (IOP) was 34 mmHg and 42 mmHg in right and left eye, respectively. Dilated funduscopic examination revealed papillary pallor, increased cup-to-disc ratio of the optic nerve in both eyes, and retinal posterior pole oedema in the LE. Optical coherence tomography (OCT) and fluorescein angiography assessment confirmed the diagnosis of a macular serous retinal detachment (RD) caused by an optic disc pit secondary to glaucoma. Combined surgical treatment with ExPress drainage device implantation, pars plana vitrectomy (PPV), and juxtapapillar laser endophotocoagulation was performed. The IOP returned to normal, as well as complete anatomical resolution of macular RD.


Assuntos
Anormalidades do Olho , Glaucoma , Degeneração Macular , Disco Óptico , Glaucoma/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33495054

RESUMO

CASE REPORT: A 58-year-old man was referred to the retina specialist for evaluation of decreased vision in the left eye (LE). At the first visit, visual acuity was 0.9 in right eye (RE) and hands movement in LE, and the intraocular pressure (IOP) was 34 mmHg and 42 mmHg in right and left eye, respectively. Dilated funduscopic examination revealed papillary pallor, increased cup-to-disc ratio of the optic nerve in both eyes, and retinal posterior pole edema in the LE. Optical coherence tomography (OCT) and fluorescein angiography assessment confirmed the diagnosis of a macular serous retinal detachment (RD) caused by an optic disc pit secondary to glaucoma. Combined surgical treatment with ExPress drainage device implantation, pars plana vitrectomy (PPV), and juxtapapillar laser endophotocoagulation was performed. IOP normalization was achieved as well as complete anatomical resolution of macular RD.

5.
Phys Rev E ; 102(3-1): 032804, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33075934

RESUMO

Experiments performed in DECLIC-DSI on board the International Space Station evidenced oscillatory modes during the directional solidification of a bulk sample of succinonitrile-based transparent alloy. The interferometric data acquired during a reference experiment, V_{p}=1 µm/s and G=19 K/cm, allowed us to reconstruct the cell shape and thus measure the cell tip position, radius, and growth velocity evolution, in order to quantify the dynamics of the oscillating cells. This study completes our previous reports [Bergeon et al., Phys. Rev. Lett. 110, 226102 (2013)10.1103/PhysRevLett.110.226102; Tourret et al., Phys. Rev. E 92, 042401 (2015)10.1103/PhysRevE.92.042401; Pereda et al., Phys. Rev. E 95, 012803 (2017)10.1103/PhysRevE.95.012803] with, to our knowledge, the first complete monitoring of the geometric cell tip characteristics variations in bulk samples. The evolution of the shape, velocity, and position of the tip of the oscillating cells is associated with an evolution of the concentration field, inaccessible experimentally but mediating the diffusive interactions between the cells. The experimental results are supported by 3D phase-field simulations which evidence the existence of transversal solute fluxes between neighboring cells that play a fundamental role in the oscillation dynamics. The dynamics of oscillation of an individual cell is analyzed using a theoretical model based on classical equations of solidification through the calculation of the phase relationships between oscillation of the different tip characteristics.

6.
Rev Neurol ; 64(8): 362-366, 2017 Apr 16.
Artigo em Espanhol | MEDLINE | ID: mdl-28368083

RESUMO

INTRODUCTION: In the last years, new technologies such as the brain-machine interfaces (BMI) have been incorporated in the rehabilitation process of subjects with stroke. These systems are able to detect motion intention, analyzing the cortical signals using different techniques such as the electroencephalography (EEG). This information could guide different interfaces such as robotic devices, electrical stimulation or virtual reality. CASE REPORT: A 40 years-old man with stroke with two months from the injury participated in this study. We used a BMI based on EEG. The subject's motion intention was analyzed calculating the event-related desynchronization. The upper limb motor function was evaluated with the Fugl-Meyer Assessment and the participant's satisfaction was evaluated using the QUEST 2.0. The intervention using a physical therapist as an interface was carried out without difficulty. CONCLUSIONS: The BMI systems detect cortical changes in a subacute stroke subject. These changes are coherent with the evolution observed using the Fugl-Meyer Assessment.


TITLE: Entrenamiento de las señales corticales a traves de un sistema BMI-EEG, evolucion e intervencion. A proposito de un caso.Introduccion. En los ultimos años estan incorporandose nuevas tecnologias en el tratamiento fisioterapeutico de pacientes con ictus, como las interfaces cerebro-maquina ­brain-machine interface (BMI)­, capaces de detectar la intencion de movimiento analizando las señales corticales por medio de diferentes tecnicas, como la electroencefalografia (EEG). Estas señales se traducen en comandos con el fin de realizar una funcion. Caso clinico. Varon de 40 años con ictus de dos meses de evolucion, en el cual se empleo un dispositivo BMI-EEG. La intencion de movimiento del sujeto se analizo calculando la desincronizacion relacionada con el evento. La funcion motora del miembro superior fue evaluada con la escala de Fugl-Meyer, y el nivel de satisfaccion del paciente, mediante el cuestionario QUEST 2.0. La intervencion se llevo a cabo sin dificultad siendo el fisioterapeuta la interfaz. Conclusiones. Los sistemas BMI-EEG detectan cambios corticales en un sujeto con ictus subagudo. Estos cambios son coherentes con los cambios observados en escalas clinicas.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Reabilitação do Acidente Vascular Cerebral/métodos , Adulto , Humanos , Masculino
7.
Phys Rev E ; 95(1-1): 012803, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28208400

RESUMO

We present a detailed analysis of oscillatory modes during three-dimensional cellular growth in a diffusive transport regime. We ground our analysis primarily on in situ observations of directional solidification experiments of a transparent succinonitrile 0.24wt% camphor alloy performed in microgravity conditions onboard the International Space Station. This study completes our previous reports [Bergeon et al., Phys. Rev. Lett. 110, 226102 (2013)10.1103/PhysRevLett.110.226102; Tourret et al., Phys. Rev. E 92, 042401 (2015)10.1103/PhysRevE.92.042401] from an experimental perspective, and results are supported by additional phase-field simulations. We analyze the influence of growth parameters, crystal orientation, and sample history on promoting oscillations, and on their spatiotemporal characteristics. Cellular patterns display a remarkably uniform oscillation period throughout the entire array, despite a high array disorder and a wide distribution of primary spacing. Oscillation inhibition may be associated to crystalline disorientation, which stems from polygonization and is manifested as pattern drifting. We determine a drifting velocity threshold above which oscillations are inhibited, thereby demonstrating that inhibition is due to cell drifting and not directly to disorientation, and also explaining the suppression of oscillations when the pulling velocity history favors drifting. Furthermore, we show that the array disorder prevents long-range coherence of oscillations, but not short-range coherence in localized ordered regions. For regions of a few cells exhibiting hexagonal (square) ordering, three (two) subarrays oscillate with a phase shift of approximately ±120^{∘} (180^{∘}), with square ordering occurring preferentially near subgrain boundaries.

8.
J Anat ; 222(5): 487-94, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23520979

RESUMO

Vascularization and blood cell circulation are crucial steps during lung development. However, how blood vessels are generated and when lung circulation is initiated is still a matter of debate. A morpho-functional analysis of pulmonary vasculature was done using human lung samples between 31 and 56 days post-fertilization (pf). The immunolocalization and expression of CD31, CD34, FLT-1, KDR and the vascular growth factor (VEGF) were investigated. The results showed that at day 31 pf, a capillary plexus is already installed, and a few primitive erythroblasts were seen for the first time within the lumen of some blood vessels. Around day 45 pf, an increase in the amount of primitive erythroblasts was detected in the parenchyma surrounding the distal segment of the bronchial tree. The expression of FLT-1, KDR, CD31 and CD34 was observed in endothelial cells of the capillary plexus and the VEGF was detected in the endodermal epithelium. Our results support the hypothesis that the initial formation of the capillary plexus around the tip of the growing airway bud occurs by vasculogenesis, probably regulated by VEGF and KDR. We also showed a very early onset of blood circulation, starting from day 34 pf, concomitant with the generation of new lung buds. In addition, the increasing number of primitive erythroblasts from week 6 onward, associated with a change in the shape of the blood vessels, suggests a remodeling process and that the generation of new distal vessels at the tip of the lung bud occurs mainly by a process of angiogenesis.


Assuntos
Vasos Sanguíneos/crescimento & desenvolvimento , Eritroblastos/citologia , Pulmão/irrigação sanguínea , Pulmão/embriologia , Antígenos CD/metabolismo , Biomarcadores/metabolismo , Vasos Sanguíneos/embriologia , Células Endoteliais/metabolismo , Células Epiteliais/metabolismo , Humanos , Pulmão/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
9.
Eur J Histochem ; 56(3): e29, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23027345

RESUMO

The lung is formed from a bud that grows and divides in a dichotomous way. A bud is a new growth center which is determined by epithelial-mesenchymal interactions where proteins of the extracellular matrix (ECM) might be involved. To understand this protein participation during human lung development, we examined the expression and distribution of proteoglycans in relation to the different types of collagens during the period in which the air conducting system is installed. Using light microscopy and immunohistochemistry we evaluate the expression of collagens (I, III and VI) and proteoglycans (decorin, biglycan and lumican) between 8 to 10 weeks post fertilization and 11 to 14 weeks of gestational age of human embryo lungs. We show that decorin, lumican and all the collagen types investigated were expressed at the epithelium-mesenchymal interface, forming a sleeve around the bronchiolar ducts. In addition, biglycan was expressed in both the endothelial cells and the smooth muscle of the blood vessels. Thus, the similar distribution pattern of collagen and proteoglycans in the early developmental stages of the human lung may be closely related to the process of dichotomous division of the bronchial tree. This study provides a new insight concerning the participation of collagens and proteoglycans in the epithelial-mesenchymal interface during the period in which the air conducting system is installed in the human fetal lung.


Assuntos
Colágeno/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Pulmão/embriologia , Proteoglicanas/metabolismo , Biglicano/metabolismo , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Decorina/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Sulfato de Queratano/metabolismo , Lumicana
10.
Cell Mol Life Sci ; 67(10): 1687-97, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20130956

RESUMO

Tauhe expression of the critical initiator cytokine TNF-alpha was strongly upregulated in vivo in acute necrotic pancreatitis (AP) in rodents and in vitro in TNF-alpha activated acinar AR42J cells. Upregulation of tnf-alpha, inos, icam-1 and il-6 occurred both in TNF-alpha receptor 1 and 2 knock-out mice, but not in TNF-alpha knock-out mice, in cerulein-induced acute pancreatitis. Chromatin immunoprecipitation analysis showed that transcriptional factors (ELK-1, SP1, NF-kappaB and EGR-1) and chromatin modification complexes (HDAC1, HDAC2, GCN5, PCAF and CBP) were recruited and/or released from the promoter in a strictly ordered mechanism. Activation of tnf-alpha gene was also accompanied by an ordered increased level of histone H3K9, H3K14 and H3K18-acetylation and H3K4 methylation, as well as H4K5 acetylation. A better knowledge of the molecular mechanisms that control tnf-alpha gene regulation will provide deeper understanding of the initiation and development of the inflammatory processes occurring in acute pancreatitis triggered by TNF-alpha cytokine.


Assuntos
Epigênese Genética , Pancreatite Necrosante Aguda/genética , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/genética , Animais , Linhagem Celular , Imunoprecipitação da Cromatina , Histonas/metabolismo , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pancreatite Necrosante Aguda/patologia , Regiões Promotoras Genéticas/genética , Processamento de Proteína Pós-Traducional , Ratos , Receptores Tipo I de Fatores de Necrose Tumoral/deficiência , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/deficiência , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Ácido Taurocólico , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/genética
11.
Sarcoidosis Vasc Diffuse Lung Dis ; 27(2): 121-30, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21319594

RESUMO

BACKGROUND: Cyclooxygenase-2, a key regulatory enzyme in the synthesis of the antifibrotic agent prostaglandin E2, is downregulated in lung tissue from patients with idiopathic pulmonary fibrosis. OBJECTIVE: To investigate the association between COX2.3050 (G --> C), COX2.8473 (C --> T) and COX2.926 (G --> C) single nucleotide polymorphisms (SNP) and the susceptibility to idiopathic pulmonary fibrosis and the progression of the disease. DESIGN: Genetic polymorphisms were analyzed in 121 out of 225 available control subjects and in all of 174 patients with idiopathic pulmonary fibrosis by real time polymerase chain reaction. Logistic regression analysis of covariance and chi-squares test were used for statistical analysis. RESULTS: While analysis of disease development did not find any significant association with single SNP genotype, a haplotype analysis revealed a strong association between the disease development and one haplotype [GC] at loci COX2.3050 and COX2.8473, and suggested a recessive genetic effect of this haplotype. Further analysis concluded that subjects having two copies of [GC] haplotype, or equivalently (GG/CC) genotype at the two SNPs, had an increased risk after adjusting for age and sex. Due to the interaction, this elevated risk increased slowly with age, and the estimated odds ratio (OR) decreased with age from OR = 1.4 at age 30 to OR = 1 at age 74 and OR = 0.96 at age SO. The OR was significantly greater than 1 up to age 66, and not significant for age older than 66. Therefore, the recessive effect of [GC] haplotype increased the risk of IPF of subjects younger than 66 years, but its effect diminished for seniors older than 66. One hundred and forty-nine patients with idiopathic pulmonary fibrosis were followed up for 33.7 +/- 2.1 months. Further analysis of disease progressions, defined by the changes in pulmonary function tests, did not reveal any association with either SNP genotypes or haplotypes. CONCLUSIONS: The carriage of double homozygote (GG/CC) at the SNP loci of COX2.3050 and COX2.8473 polymorphisms may increase the susceptibility to idiopathic pulmonary fibrosis, by approximately 1.4 folds at age 30 and by a smaller fold greater than 1 up to age 66 years, but not the progression of the disease. These findings may help to improve our understanding of idiopathic pulmonary fibrosis pathogenesis and may lead to the development of new therapeutic strategies.


Assuntos
Ciclo-Oxigenase 2/genética , Predisposição Genética para Doença/genética , Fibrose Pulmonar Idiopática/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Frequência do Gene , Haplótipos , Humanos , Desequilíbrio de Ligação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade
12.
Arch. bronconeumol. (Ed. impr.) ; 45(10): 529-529, oct. 2009.
Artigo em Espanhol | IBECS | ID: ibc-75949

RESUMO

Introducción: Se ha descrito la existencia de una disminución en la expresión de ciclooxigenasa 2 (COX-2) y de prostaglandina-E2 (PGE-2) en la fibrogénesis pulmonar. La PGE-2 es un mediador antifibrótico. Los miofibroblastos desempeñan un importante papel en la fibrogénesis. Los miofibroblastos pueden formarse a partir de fibroblastos (transición fibroblasto-miofibroblasto) y de células epiteliales (transición epitelio-mesenquimal). El objetivo es estudiar la expresión de COX-2 y la síntesis de PGE2 en la inducción de la formación de miofibroblastos.Métodos: Mediante biopsia pulmonar se obtuvieron fibroblastos normales de sujetos con neumotórax (n=5) y fibroblastos de pacientes con fibrosis pulmonar idiopática (FPI) (n=5). Para el estudio de la función epitelial se utilizaron células epiteliales inmortales A549. Se realizó inmunohistoquímica (IHC) y Western blot para la determinación de COX-2 y α-SMA (marcador de miofibroblastos). Mediante ELISA se estudio la síntesis de PGE2. La proliferación celular se valoró mediante la incorporación nuclear de un análogo de nucleósido.Resultados: Los fibroblastos de la FPI presentan mayores niveles de ß-SMA comparados con los fibroblastos control. Ambos presentan una expresión indetectable de COX-2. Después de la estimulación con interleucina 1ß (IL-1ß), los fibroblastos control expresan mayores niveles de COX-2 que los fibroblastos fibróticos. Los miofibroblastos detectados mediante IHC no expresaron COX-2. Los fibroblastos tratados con TGF-ß1 expresan α-SMA, en forma, dosis y tiempo dependiente, tanto en fibroblastos fibróticos como en controles. A549 tratadas con TGF-ß1 cambian su fenotipo, expresando fibras de estrés relacionadas con la formación de miofibroblastos (α-SMA+). Los miofibroblastos obtenidos de tratar fibroblatos o A549 con TGF-ß1 muestran un descenso de los niveles de COX-2 y PGE-2 tras estimulación con IL-1ß. No hubo variaciones en la proliferación celular(AU)


Conclusiones: Los miofibroblastos se caracterizan por una alteración en la regulación de la expresión de COX-2 y en la síntesis de PGE-2, tanto en los transformados a partir de fibroblastos como de células epiteliales(AU)


Assuntos
Humanos , Masculino , Feminino , Ciclo-Oxigenase 2 , Ciclo-Oxigenase 2/uso terapêutico , Ciclo-Oxigenase 2 , Ciclo-Oxigenase 2/efeitos adversos , Fibrose Pulmonar , Fibrose Pulmonar/terapia , Fibroblastos , Inibidores de Ciclo-Oxigenase 2 , Dinoprostona , Biópsia
13.
Opt Lett ; 34(15): 2288-90, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19649073

RESUMO

We present a simple technique to integrate an electro-optic Q switch in a periodically poled bulk lithium niobate crystal bounded by two unpoled (monodomain) regions. The technique exploits the high sensitivity to low applied electric fields of the total internal reflection condition in the periodic poled-unpoled boundary for the small grazing incidence angles associated with the diffraction of a focused Gaussian beam that propagates in the periodically poled region with its axis parallel to the boundary. When the arrangement is placed intracavity to a 1064 nm diode-pumped Nd(3+):YVO(4) laser, it performs simultaneously as a Q switch and as a second-harmonic generator, with Q switching starting at applied voltages as low as 1 V over a 500 microm thickness and with no additional optical elements.

14.
Eur Respir J ; 32(4): 1004-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18508830

RESUMO

Angiotensin II is a growth factor that plays a key role in the physiopathology of idiopathic pulmonary fibrosis (IPF). A nucleotide substitution of an adenine instead of a guanine (G-6A) in the proximal promoter region of angiotensinogen (AGT), the precursor of angiotensin II, has been associated with an increased gene transcription rate. In order to investigate whether the G-6A polymorphism of the AGT gene is associated with IPF development, severity and progression, the present study utilised a case-control study design and genotyped G-6A in 219 patients with IPF and 224 control subjects. The distribution of G-6A genotypes and alleles did not significantly differ between cases and controls. The G-6A polymorphism of the AGT gene was not associated with disease severity at diagnosis. The presence of the A allele was strongly associated with increased alveolar arterial oxygen tension difference during follow-up, after controlling for the confounding factors. Higher alveolar arterial oxygen tension changes over time were observed in patients with the AA genotype (0.37+/-0.7 mmHg (0.049+/-0.093 kPa) per month) compared to GA genotype (0.12+/-1 mmHg (0.016+/-0.133 kPa) per month) and GG genotype (0.2+/-0.6 mmHg (0.027+/-0.080 kPa) per month). G-6A polymorphism of the angiotensinogen gene is associated with idiopathic pulmonary fibrosis progression but not with disease predisposition. This polymorphism could have a predictive significance in idiopathic pulmonary fibrosis patients.


Assuntos
Angiotensinogênio/genética , Fibrose Pulmonar Idiopática/genética , Polimorfismo Genético , Adulto , Idoso , Alelos , Progressão da Doença , Feminino , Genótipo , Guanina/química , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Troca Gasosa Pulmonar
15.
J Dairy Sci ; 90(3): 1081-93, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17297083

RESUMO

The effect of ultra-high pressure homogenization (UHPH) on microbial and physicochemical shelf life of milk during storage at 4 degrees C was studied and compared with a conventional heat preservation technology used in industry. Milk was standardized at 3.5% fat and was processed using a Stansted high-pressure homogenizer. High-pressure treatments applied were 100, 200, and 300 MPa (single stage) with a milk inlet temperature of 40 degrees C, and 200 and 300 MPa (single stage) with a milk inlet temperature of 30 degrees C. The UHPH-treated milks were compared with high-pasteurized milk (PA; 90 degrees C for 15 s). The microbiological quality was studied by enumerating total counts, psychrotropic bacteria, lactococci, lactobacilli, enterococci, coliforms, spores, and Pseudomonas. Physicochemical parameters assessed in milks were viscosity, color, pH, acidity, rate of creaming, particle size, and residual peroxidase and phosphatase activities. Immediately after treatment, UHPH was as efficient (99.99%) in reducing psychrotrophic, lactococci, and total bacteria as was the PA treatment, reaching reductions of 3.5 log cfu/mL. Coliforms, lactobacilli, and enterococci were eliminated. Microbial results of treated milks during storage at 4 degrees C showed that UHPH treatment produced milk with a microbial shelf life between 14 and 18 d, similar to that achieved for PA milk. The UHPH treatments reduced the L* value of treated milks and induced a reduction in viscosity values of milks treated at 200 MPa compared with PA milks; however, these differences would not be appreciated by consumers. In spite of the fat aggregates detected in milks treated at 300 MPa, no creaming was observed in any UHPH-treated milk. Hence, alternative methods such as UHPH may give new opportunities to develop fluid milk with an equivalent shelf life to that of PA milk in terms of microbial and physicochemical characteristics.


Assuntos
Bactérias/isolamento & purificação , Manipulação de Alimentos/métodos , Pressão Hidrostática , Leite/química , Leite/microbiologia , Animais , Cor/normas , Conservação de Alimentos/métodos , Glicolipídeos/análise , Glicoproteínas/análise , Concentração de Íons de Hidrogênio , Gotículas Lipídicas , Leite/enzimologia , Leite/normas , Tamanho da Partícula , Peroxidase/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Temperatura , Fatores de Tempo , Viscosidade
16.
Cell Mol Biol (Noisy-le-grand) ; 53 Suppl: OL1010-7, 2007 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-18184479

RESUMO

Hepatic gamma-cystathionase, a rate-limiting enzyme for the synthesis of L-cysteine from L-methionine in the trans-sulphuration pathway, exhibits significantly higher activity in the newly born infant as compared to the fetus. The aim of this work was: 1) To determine whether the increase in gamma-cystathionase activity occurring in the fetal-to-neonatal transition is due to up-regulation of its mRNA and protein, 2) To elucidate the mechanisms responsible for this increase in gamma-cystathionase activity. Our results show that expression of gamma-cystathionase at both the mRNA and protein levels was higher in newborn than in fetal liver. gamma-Cystathionase activity in fetal hepatocytes in vitro increased when incubated with tert-butyl-hydroperoxide at low concentration (0.01 mM). Hence, moderate oxidative stress would act as a signal to up-regulate gamma-cystathionase in the fetal to neonatal transition. Stress hormones, such as phenylephrine or glucagon also increased gamma-cystathionase activity in fetal hepatocytes. We also report a competitive inhibition of purified gamma-cystathionase by L-cysteine, which would help to maintain physiological low L-cysteine levels in hepatocytes. In conclusion, our results show that increased hepatic gamma-cystathionase activity in the fetal-to-neonatal transition is due to up-regulation of its gene expression mediated by stress hormones together with the physiological oxidative stress that occurs at birth.


Assuntos
Cistationina gama-Liase/biossíntese , Fígado/enzimologia , Estresse Oxidativo/fisiologia , Animais , Animais Recém-Nascidos , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/enzimologia , AMP Cíclico/farmacologia , Cistationina gama-Liase/antagonistas & inibidores , Cistationina gama-Liase/genética , Cisteína/farmacologia , Indução Enzimática/efeitos dos fármacos , Feto/enzimologia , Glucagon/farmacologia , Glutationa/biossíntese , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Fígado/embriologia , Fígado/crescimento & desenvolvimento , Metionina/metabolismo , Fenilefrina/farmacologia , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , terc-Butil Hidroperóxido/farmacologia
17.
Br J Pharmacol ; 149(4): 450-5, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16953192

RESUMO

BACKGROUND AND PURPOSE: Pentoxifylline exhibits rheological properties that improve microvascular flow and it is widely used in vascular perfusion disorders. It also exhibits marked anti-inflammatory properties by inhibiting tumour necrosis factor alpha production. Thiopental is one of the most widely used drugs for rapid induction of anaesthesia. During experimental studies on the treatment of acute pancreatitis, we observed that when pentoxifylline was administered after anaesthesia with thiopental, most of the rats exhibited dyspnea, signs of pulmonary oedema and died. The aim of the work described here was to investigate the cause of the unexpected toxic effect of the combined treatment with thiopental and pentoxifylline. EXPERIMENTAL APPROACH: Pulmonary vascular permeability and arterial blood gases were measured, and a histological analysis was performed. The possible role of haemodynamic changes in the formation of pulmonary oedema was also assessed. KEY RESULTS: Co-administration of pentoxifylline and thiopental increased pulmonary vascular permeability and markedly decreased arterial pO2, with one third of rats suffering from hypoxemia. This combined treatment caused death by acute pulmonary oedema in 27% of normal rats and aggravated the respiratory insufficiency associated with acute pancreatitis in which the mortality rate increased to 60%. This pulmonary oedema was not mediated by cardiac failure or by pulmonary hypertension. CONCLUSIONS AND IMPLICATIONS: Co-administration of pharmacological doses of pentoxifylline and thiopental caused pulmonary oedema and death in rats. Consequently, pentoxifylline should not be administered when anaesthesia is induced with thiopental to avoid any possible risk of acute pulmonary oedema and death in humans.


Assuntos
Anestésicos Intravenosos/efeitos adversos , Pentoxifilina/efeitos adversos , Edema Pulmonar/induzido quimicamente , Tiopental/efeitos adversos , Vasodilatadores/efeitos adversos , Doença Aguda , Anestésicos Intravenosos/administração & dosagem , Animais , Interações Medicamentosas , Injeções Intraperitoneais , Masculino , Pancreatite , Pentoxifilina/administração & dosagem , Edema Pulmonar/patologia , Ratos , Ratos Wistar , Tiopental/administração & dosagem , Vasodilatadores/administração & dosagem
18.
Ital J Anat Embryol ; 110(2 Suppl 1): 167-74, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16101035

RESUMO

Since the last decade the Yolk sac (YS) has been a topic of increasing interest due to the growing use of high-resolution sonography in early determination of pregnancy. Human YS shape and diameter are indicators of viability of pregnancy during the early embryonic period. Nevertheless, the major interest concerns the vital function it plays in early embryo growth and development. Two compartments are recognized in this organ: the yolk sac proper and the vitelline stalk. In this study we report the identification and partial characterization of a glomus-like body in the wall of the secondary YS in humans. A detailed structural description is also presented on the time course of formation of this new structure, at precisely sequential stages between 4-8 wk post-conception. The significance of this new compartment on the YS function is analyzed. Light and scanning electron microscopy were used to investigate the microstructure of the YS and the vitelline stalk during the first 8 wk of development. Ten YSs were collected from embryos (aged between 24-50 days) obtained from emergency salpingectomies due to tubal ectopic pregnancy. From 5 wk onward a new structure was observed in the YS located near the apex of the pear-shaped yolk vesicle and closed to the connecting stalk. We designate this differentiation as glomus-like body. This structure is 1-1.5 mm long and merged from a pocket-like structure of the extraembryonic splanchnic mesoderm of the YS wall. It likely represents an area of convergence of the vascular network of the YS wall. Our findings underline the remarkable complexity of the human secondary yolk sac during early development. The detailed description of the microanatomy of this vital organ is of theoretical and practical interest in order to unravel the mechanisms used by the yolk sac to transport nutrients to the embryo.


Assuntos
Feto Abortado/ultraestrutura , Desenvolvimento Embrionário/fisiologia , Microcirculação/ultraestrutura , Saco Vitelino/irrigação sanguínea , Saco Vitelino/ultraestrutura , Feto Abortado/embriologia , Feto Abortado/fisiologia , Pressão Sanguínea/fisiologia , Feminino , Células Germinativas/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Humanos , Mesoderma/citologia , Mesoderma/fisiologia , Microcirculação/crescimento & desenvolvimento , Microscopia Eletrônica de Varredura , Gravidez , Fluxo Sanguíneo Regional/fisiologia , Ducto Vitelino/irrigação sanguínea , Ducto Vitelino/crescimento & desenvolvimento , Ducto Vitelino/ultraestrutura , Saco Vitelino/embriologia
20.
Mycoses ; 46(3-4): 126-31, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12870201

RESUMO

The aim of the study was to compare the efficacy and tolerability of flutrimazole 1% powder vs. bifonazole 1% powder in treating tinea pedis. A multicentre, double blind, randomized, parallel and comparative study was conducted. Two hundred and twenty-two patients with clinically and mycologically confirmed tinea pedis were randomized to flutrimazole (n = 136) or bifonazole (n = 138) 1% powder applied twice daily for 4 weeks. The corresponding clinical cure rates were assessed at 2 and 4 weeks of treatment, and the global (clinical and mycological) cure rates were determined at the fourth week. Clinical cure rates were 83.5 and 82.4% for flutrimazole and bifonazole, respectively (95% CI: -0.0806 to 0.1009). Global cure rates were observed in 65.3 and 70.1% of patients treated with flutrimazole and bifonazole, respectively (95% CI: -0.0828 to 0.1779). Three non serious adverse events at the application site--itching (one patient per group) and dishydrotic eczema (one patient treated with flutrimazole)--were recorded during the study. These results support that flutrimazol 1% powder applied twice daily for a duration of 4 weeks is highly effective in the treatment of tinea pedis, showing a similar therapeutic profile with that of bifonazole 1% powder.


Assuntos
Antifúngicos/uso terapêutico , Clotrimazol/análogos & derivados , Clotrimazol/uso terapêutico , Tinha dos Pés/tratamento farmacológico , Adolescente , Adulto , Antifúngicos/administração & dosagem , Antifúngicos/efeitos adversos , Clotrimazol/administração & dosagem , Clotrimazol/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Imidazóis/efeitos adversos , Imidazóis/uso terapêutico , Masculino , Pós , Tinha dos Pés/microbiologia , Resultado do Tratamento , Trichophyton/efeitos dos fármacos
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