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1.
Phys Rev E ; 107(5-2): 055212, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37329056

RESUMEN

A recent numerical treatment of data obtained by the Parker Solar Probe spacecraft describes the electron concentration in solar wind as a function of the heliocentric distance based on a Kappa distribution with spectral index κ=5. In this work, we derive and, subsequently, solve an entirely different class of nonlinear partial differential equations describing the one-dimensional diffusion of a suprathermal gas. The theory is applied to describe the aforementioned data and we find a spectral index κ≳1.5 providing the widely acknowledged identification of Kappa electrons in solar wind. We also find that suprathermal effects increase the length scale of classical diffusion by one order of magnitude. Such a result does not depend on the microscopic details of the diffusion coefficient since our theory is based on a macroscopic formulation. Forthcoming extensions of our theory by including magnetic fields and relating our formulation to nonextensive statistics are briefly addressed.


Asunto(s)
Electrones , Viento , Difusión
3.
Biosens Bioelectron ; 67: 516-23, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25256781

RESUMEN

In this work, a "bio-electronic nose" for vapour phase detection of odorant molecules based on surface acoustic wave (SAW) resonators is presented. The biosensor system is composed of an array of five SAW resonators coated with three types of odorant-binding proteins (OBPs): the wild-type OBP from bovine (wtbOBP), a double-mutant of the OBP from bovine (dmbOBP), and the wild-type OBP from pig (wtpOBP). High resolution deposition of OBPs onto the active area of SAW resonators was implemented through laser-induced forward transfer (LIFT). The resonant frequency shifts of the SAW resonators after the deposition of the biomolecules confirmed the immobilisation of the proteins onto the Al/Au inter-digital transducers (IDTs). In addition, a low increase of insertion losses with a limited degradation of Q-factors is reported. The "bio-electronic nose" fabricated by LIFT is tested in nitrogen upon exposure to separated concentrations of R-(-)-1-octen-3-ol (octenol) and R-(-)-carvone (carvone) vapours. The "bio-electronic nose" showed low detection limits for the tested compounds (i.e. 0.48 ppm for the detection of octenol, and 0.74 ppm for the detection of carvone). In addition, the bio-sensing system was able to discriminate the octenol molecules from the carvone molecules, making it pertinent for the assessment of food contamination by moulds, or for the evaluation of indoor air quality in buildings.


Asunto(s)
Técnicas Biosensibles , Nariz Electrónica , Odorantes/análisis , Receptores Odorantes/química , Animales , Bovinos , Límite de Detección , Sonido , Porcinos
4.
Vet Microbiol ; 168(2-4): 357-64, 2014 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-24332702

RESUMEN

The systemic and respiratory local immune response induced by the intradermal administration of a commercial inactivated Mycoplasma hyopneumoniae whole-cell vaccine (Porcilis(®) MHYO ID ONCE - MSD AH) in comparison with two commercial vaccines administered via the intramuscular route and a negative control (adjuvant only) was investigated. Forty conventional M. hyopneumoniae-free pigs were randomly assigned to four groups (ten animals each): Group A=intradermal administration of the test vaccine by using the needle-less IDAL(®) vaccinator at a dose of 0.2 ml; Group B=intramuscular administration of a commercially available vaccine (vaccine B); Group C=intramuscular administration of the adjuvant only (2 ml of X-solve adjuvant); Group D=intramuscular administration of a commercially available vaccine (vaccine D). Pigs were vaccinated at 28 days of age. Blood and bronchoalveolar lavage (BAL) fluid samples were collected at vaccination (blood only), 4 and 8 weeks post-vaccination. Serum and BAL fluid were tested for the presence of antibodies by ELISA test. Peripheral blood monomorphonuclear cells (PBMC) were isolated to quantify the number of IFN-γ secreting cells by ELISpot. Moreover, cytokine gene expression from the BAL fluid was performed. Total antibodies against M. hyopneumoniae and specific IgG were detected in serum of intradermally and intramuscularly (vaccine B only) vaccinated pigs at 4 and 8 weeks post-vaccination. M. hyopneumoniae specific IgA were detected in BAL fluid from vaccinated animals (Groups A and B) but not from controls and animals vaccinated with the bacterin D (p<0.05). Significantly higher gene expression of IL-10 was observed in the BAL fluid at week 8 post-vaccination in the intradermally vaccinated pigs (p<0.05). The results support that the intradermal administration of an adjuvanted bacterin induces both systemic and mucosal immune responses. Moreover, the intramuscularly administered commercial vaccines each had a different ability to stimulate the immune response both systemically and locally.


Asunto(s)
Vacunas Bacterianas/administración & dosificación , Mycoplasma hyopneumoniae/inmunología , Neumonía Porcina por Mycoplasma/inmunología , Neumonía Porcina por Mycoplasma/prevención & control , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Vacunas Bacterianas/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Inmunoglobulina A/inmunología , Inyecciones Intradérmicas , Inyecciones Intramusculares , Interferón gamma/inmunología , Interleucina-10/genética , Interleucina-10/inmunología , Leucocitos Mononucleares/inmunología , Masculino , Sus scrofa/inmunología , Porcinos/inmunología , Vacunación/métodos , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología
5.
Biosens Bioelectron ; 41: 328-34, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22981410

RESUMEN

In this paper, we present an array of biosensors for vapour phase detection of odorant molecules based on surface acoustic wave (SAW) resonators coated with odorant-binding proteins (OBPs). For the first time, the sensing capabilities of three different OBPs, as sensitive layers for SAW devices, are studied and compared. The SAW biosensor array is composed of three SAW devices coated by the droplet method with the wild-type OBP from cow (wtbOBP), a double mutant of the OBP from cow (dmbOBP) and the wild-type OBP from pig (wtpOBP). An uncoated device is used to compensate the variations of the environmental parameters. The SAW devices consist of two-port resonators fabricated on quartz (ST-cut, x propagation) with electrodes made of aluminium covered with a thin gold film (2 nm thick). The obtained surface densities of OBP layers are between 1.18×10(-6) kg/m(2) and 2.31×10(-6) kg/m(2) and were calculated measuring the resonant frequency shift of the SAW devices after the coating. The SAW biosensor array was tested in nitrogen upon exposure to vapours of R-(-)-1-octen-3-ol (octenol), in the range of concentration between 13 and 61 ppm, and R-(-)-carvone (carvone), in the range between 9 and 80 ppm. The highest sensitivity for detection of octenol (25.9 Hz/ppm) was obtained using the wtpOBP-based SAW biosensor, while the highest sensitivity for detection of carvone (9.2 Hz/ppm) was obtained using the dmbOBP-based SAW biosensor.


Asunto(s)
Técnicas Biosensibles/instrumentación , Proteínas Portadoras/química , Gases/análisis , Sistemas Microelectromecánicos/instrumentación , Análisis por Micromatrices/instrumentación , Odorantes/análisis , Mapeo de Interacción de Proteínas/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Sonido
6.
J Synchrotron Radiat ; 19(Pt 6): 1015-20, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23093764

RESUMEN

A novel beam position monitor, operated at zero bias voltage, based on high-quality chemical-vapor-deposition single-crystal Schottky diamond for use under intense synchrotron X-ray beams was fabricated and tested. The total thickness of the diamond thin-film beam monitor is about 60 µm. The diamond beam monitor was inserted in the B16 beamline of the Diamond Light Source synchrotron in Harwell (UK). The device was characterized under monochromatic high-flux X-ray beams from 6 to 20 keV and a micro-focused 10 keV beam with a spot size of approximately 2 µm × 3 µm square. Time response, linearity and position sensitivity were investigated. Device response uniformity was measured by a raster scan of the diamond surface with the micro-focused beam. Transmissivity and spectral responsivity versus beam energy were also measured, showing excellent performance of the new thin-film single-crystal diamond beam monitor.

7.
J Hum Virol ; 4(6): 317-28, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-12082398

RESUMEN

OBJECTIVE: Emergence of human immunodeficiency virus type-1 (HIV-1) genotypic drug resistance is generally attributed to noncompliance, poorly absorbed drugs, or drug-to-drug interaction. Attempts to determine emerging genotypic drug resistance from study subjects on highly active antiretroviral therapy (HAART) relied on insensitive polymerase chain reaction (PCR) techniques, revealing wild type HIV-1 or precursor resistant genotypes from few plasma samples successfully amplified with <50 copies/mL. STUDY DESIGN/METHODS: In this analysis, using Applied Biosystems' ViroSeq HIV-1 Genotyping Systems, Version 2.0 (Applied Biosystems, Foster City, CA, USA) and the supplemental, for research use only, nested PCR primers, genotypic drug resistance was determined in longitudinal plasma samples from 11 study subjects on HAART. RESULTS: In 4 of 11 study subjects, newly emerging genotypic primary resistant mutations were detected in plasma samples with <50 copies/mL. Most of these primary drug-resistant mutations were detected in subsequent longitudinal samples with detectable viral load (viral breakthrough). CONCLUSIONS: This analysis suggests sufficient viral replication <50 copies/mL to generate genotypic drug resistance in study subjects on suppressive HAART.


Asunto(s)
Fármacos Anti-VIH/farmacología , Farmacorresistencia Viral/genética , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Mutación , ARN Viral/efectos de los fármacos , Inhibidores de la Transcriptasa Inversa/farmacología , Terapia Antirretroviral Altamente Activa , Genotipo , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/farmacología , VIH-1/clasificación , VIH-1/genética , Humanos , Indinavir/farmacología , Lamivudine/farmacología , Estudios Longitudinales , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ritonavir/farmacología , Carga Viral , Zidovudina/farmacología
8.
Free Radic Biol Med ; 24(2): 370-6, 1998 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9433913

RESUMEN

The isolation to purity of a rat liver mitochondrial thioredoxin reductase is reported. The mitochondrial enzyme shows a chromatographic behavior different from that of the cytosolic enzyme. The purified enzyme, after sodium dodecylsulfate-polyacrylamide gel electrophoresis, yields a single band with a molecular weight of approximately 54 kDa. The apparent Km for E. coli thioredoxin is about 13 microM, while the apparent Km for 5,5'-dithiobis (2-nitrobenzoic acid) is 530 microM, values comparable to those reported for the cytosolic enzyme. Mitochondrial thioredoxin reductase, in addition to its natural substrate thioredoxin, is also able to reduce chemically unrelated compounds such as 5,5 '-dithiobis (2-nitrobenzoic acid), selenite, and alloxan; the enzyme is inhibited by classical inhibitors of the cytosolic enzyme such as 1-chloro-2,4-dinitrobenzene and 13-cis-retinoic acid. A strong inhibitory action is also elicited by Mn2+ and Zn2+ ions. Thiol status appears critically involved in the control of membrane permeability and, therefore, a thiol/disulfide transition involving reduced pyridine nucleotides, matrix soluble thiols, and inner membrane thiols appears to play a fundamental role. The potential role of thioredoxin/thioredoxin reductase system in the control and redox regulation of the mitochondrial membrane permeability, is discussed.


Asunto(s)
Membranas Intracelulares/efectos de los fármacos , Mitocondrias Hepáticas/enzimología , Reductasa de Tiorredoxina-Disulfuro/aislamiento & purificación , Reductasa de Tiorredoxina-Disulfuro/metabolismo , Aloxano/metabolismo , Animales , Calcio/metabolismo , Calcio/farmacología , Dinitroclorobenceno/farmacología , Ácido Ditionitrobenzoico/metabolismo , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/farmacología , Isotretinoína/farmacología , Manganeso/farmacología , Peso Molecular , Oxidación-Reducción , Permeabilidad/efectos de los fármacos , Ratas , Selenito de Sodio/metabolismo , Reductasa de Tiorredoxina-Disulfuro/antagonistas & inhibidores , Zinc/farmacología
9.
Arch Biochem Biophys ; 342(1): 22-8, 1997 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-9185610

RESUMEN

This work addresses a correlation between the redox state of pyridine nucleotides and that of sulfhydryl groups of the mitochondrial membranes. Several major observations emerge: (1) Conditions leading to an oxidation of the pyridine nucleotides such as incubation with tert-butyl hydroperoxide or acetoacetate determine a decrease of total mitochondrial sulfhydryl groups. Glutathione does not follow the same pattern since it decreases in the presence of tert-butyl hydroperoxide but not in the presence of acetoacetate. In addition, only in the presence of tert-butyl hydroperoxide is the decrease of sulfhydryl groups concomitant with a membrane protein polymerization, observed by polyacrylamide gel electrophoresis. (2) Under all conditions tested, the oxidation of sulfhydryl groups is further stimulated by the presence of calcium and phosphate ions. (3) Respiratory substrates, which prevent the swelling of mitochondria, also partially prevent the decrease of sulfhydryl groups.


Asunto(s)
Membranas Intracelulares/metabolismo , Mitocondrias Hepáticas/metabolismo , NADP/metabolismo , NAD/metabolismo , Compuestos de Sulfhidrilo/metabolismo , Animales , Calcio/metabolismo , Electroforesis en Gel de Poliacrilamida , Oxidación-Reducción , Ratas
10.
J Nurse Midwifery ; 41(2): 173-87, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8691277

RESUMEN

This article provides a review of common adult musculoskeletal disorders including diagnosis and treatment guidelines to assist certified nurse-midwives in their role as primary care providers. Disorders requiring referral as well as signs and symptoms indicating potentially serious underlying problems are emphasized.


Asunto(s)
Enfermedades Musculoesqueléticas/terapia , Enfermeras Obstetrices , Atención Primaria de Salud , Adulto , Antiinflamatorios no Esteroideos/uso terapéutico , Femenino , Humanos , Dolor de la Región Lumbar/diagnóstico , Dolor de la Región Lumbar/enfermería , Dolor de la Región Lumbar/terapia , Enfermedades Musculoesqueléticas/diagnóstico , Enfermedades Musculoesqueléticas/enfermería , Evaluación en Enfermería , Estados Unidos , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/enfermería , Heridas y Lesiones/terapia
11.
Sabouraudia ; 15(1): 51-7, 1977 Mar.
Artículo en Español | MEDLINE | ID: mdl-857328

RESUMEN

By using the double pour plate method, Yeasts Extract Agar (YE) which contained a high concentration of chloramphenicol-streptomycin sulfate and cycloheximide,, and by inoculating mice intraperitoneally, we succeed in the isolation of different strains of Coccidicides immitis from 12 samples of the soils collected in the province of San Luis and from 1 of the province of Mendoza (Argentina), a 70% of the samples turned out positive. Identification of the strains was based on macro- and micro-morphology of the colonies, pathogenicity for mice and the capacity to transform in shaked cultures.


Asunto(s)
Coccidioides/aislamiento & purificación , Microbiología del Suelo , Animales , Argentina , Coccidioides/crecimiento & desarrollo , Coccidioides/patogenicidad , Medios de Cultivo , Ratones
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