The combined effect of formulation and pH on properties of polyethylene oxide composite fiber containing egg albumen protein.

The aim of this work was to elucidate the influence of egg white albumen (EA) protein loaded on the electrospinning of PEO solutions under different concentrations and pHs conditions. Properties of the electrospun fiber mats, such as morphology, thermal properties, and wettability were analyzed. In addition, rheological behavior of the polymer solutions was measured to explain the electrospinnability for fiber formation. The rheological results showed that the addition of EA protein affects the molecular entanglement required to electrospin PEO, being able to incorporate up to 75wt% EA protein. The diameter of most of the PEO/EA fibers was in the range of 200-400nm. When comparing the effect of concentration and pH of the electrospinning solution, the morphology of the fibers was found to be mainly affected by the second one. FTIR analysis of the blend fibers confirmed the presence of the protein and revealed that the secondary structure changed with pH. From a thermodynamic point of view, the EA protein and PEO showed a high degree of mutual incompatibility. The presence of EA protein influenced PEO polymer thermal behavior, lowering its melting point and decreasing the quantity of PEO crystallites. All the PEO/EA electrospun fiber mats showed rapid water absorption, which increased as PEO concentration became higher, and similarly, when lowering protein concentration.

Relation between concentration and shear-extensional rheology properties of xanthan and guar gum solutions.

The influence of concentration on the shear and extensional rheology properties of aqueous solutions of xanthan and guar gums was studied in this work. Shear rheology involved small amplitude oscillatory shear (SAOS), flow curves and transient flow, while the extensional rheology was analyzed using hyperbolic contraction flow. In addition, the mechanical properties during solutions manufacture were monitored in situ through the evolution of torque with processing time by mixing rheometry. The results showed that the hydrocolloids exert a great influence on the process rheokinetics and on the resulting rheological response. SAOS tests showed that the xanthan gum solutions behaved as weak gels, whereas guar gum solutions suggest the presence of entanglement and the formation of a viscoelastic, gel-like structure. All the systems exhibited shear-thinning behaviour. Guar gum solutions obeyed the Cox-Merz rule, with some divergence at high rates for the more concentrated solutions, while the Cox-Merz rule was not followed for xanthan gum in the range of concentration studied. The extensional viscosity exhibited an extensional-thinning behaviour within the strain range used and all solutions were characterized by a high Trouton ratio.

Valorization of phosphogypsum waste as asphaltic bitumen modifier.

The accumulation of phosphogypsum waste from the fertilizer industries, which remain in regulated stacks occupying considerable land resources, is causing significant environment problems worldwide. In that sense, the scientific community is being pressured to find alternative ways for their disposal. In this research, we propose a novel application for phosphogypsum waste, as a modifier of bitumen for flexible road pavements. Viscous flow tests carried out on bitumen modified with a phosphogypsum waste and doped with sulfuric acid demonstrated an extraordinary increase in viscosity, at 60°C, when compared to a counterpart sample which had been modified with gypsum, the main component of phosphogypsum. Similarly, a significant improvement in the viscoelastic response of the resulting material at high temperatures was also found. FTIR (Fourier transform infrared spectroscopy) scans provided evidences of the existence of chemical reactions involving phosphorus, as revealed by a new absorption band from 1060 to 1180cm(-1), related to COP vibrations. This result points at phosphorus contained in the phosphogypsum impurities to be the actual "modifying" substance. Furthermore, no COP band was observed in the absence of sulfuric acid, which seems to be the "promoting" agent of this type of bond.

Manejo de la vía aérea bajo control fibrobroncoscópico en un paciente adulto con epiglotitis aguda / No disponible

No disponible

[Otoacoustic emissions screening as early identification of hearing loss in newborns]. / Otoemisiones acústicas como prueba de cribado para la detección precoz de la hipoacusia en recién nacidos.

The aim of this study was to examine the results of transient evoked otoacoustic emissions (TEOAE) as screening test for hearing impairment in newborn infants. We examined 9.951 of 11.405 infants born in our city from January 1st, 1995, to December 31st, 1998. A TEOAE test was performed prior to discharge and repeated one week later in cases who failed the first TEOAE. In case of suspected hearing loss auditory brainstem response (ABR) was performed 3 months later. Hearing loss was defined as ABR threshold > 20 dB. 157 infants (1.5%) were identified with hearing loss. Screening with TEOAE was sufficiently sensitive in identification of congenital hearing impairment and the efficacy increased with the experience.

Otoemisiones acústicas como prueba de cribado para la detección precoz de la hipoacusia en recién nacidos / Otoacoustic emissions screening in early identification of hearing loss in newborn

El objetivo de este trabajo fue presentar los resultados de las otoemisiones acústicas evocadas transitorias (OEAT) al utilizarlas como test de cribaje para la detección de hipoacusias en recién nacidos. Nosotros estudiamos 9.951 de los 11.405 recién nacidos en nuestra ciudad, desde el 1 de enero de 1995 al 31 de diciembre de 1998. Se realizaron OEAT a los neonatos antes del alta hospitalaria y se les repitieron a la semana si fallaron las primeras OEAT. Aquellos niños con sospecha de hipoacusia fueron sometidos a potenciales evocados auditivos del tronco cerebral (PEATC) a los 3 meses. Se consideró hipoacusia cuando no se detectó en los PEATC onda V a 20 dB. Ciento cincuenta y siete niños (1,5 por ciento) tuvieron déficit auditivo. El cribaje con OEAT fue suficientemente sensible en la identificación de hipoacusias congénitas, aumentando la eficacia de la prueba conforme mejoraba la experiencia del explorador (AU)

The aim of this study was to examine the results of transient evoked otoacoustic emissions (TEOAE) as screening test for hearing impairment in newborn infants. We examined 9.951 of 11.405 infants born in our city from January 1st, 1995, to December 31st, 1998. A TEOAE test was performed prior to discharge and repeated one week later in cases who failed the first TEOAE. In case of suspected hearing loss auditory brainstem response (ABR) was performed 3 months later. Hearing loss was defined as ABR threshold > 20 dB. 157 infants (1.5%) were identified with hearing loss. Screening with TEOAE was sufficiently sensitive in identification of congenital hearing impairment and the efficacy increased with the experience (AU)

El problema del seguimiento en un programa de detección precoz de sordera / The problem with monitoring in a deafness early detection program

Con la llegada de los avances tecnológicos a la valoración de la audición en los recién nacidos, ha sido posible la implantación del cribaje auditivo universal. Pero uno de los mayores problemas de estos programas es el pobre seguimiento de los niños que fallan el test inicial del cribado. Nosotros apreciamos una ventaja si se realiza el test y retest a los neonatos antes de que abandonen el hospital (AU)

[Primary carcinoma of the trachea. Report of 2 cases]. / Carcinoma primitivo de tráquea. A propósito de dos casos.

Tumours of the trachea remain relatively rare, the incidence of tracheal carcinomata is less than 0.1 per cent. Tumours of the larynx and lungs are, respectively, 75 and 180 times more frequent than malignant lesions of windpipe. Two patients with primary tracheal tumours were evaluated. The present study was undertaken in order to describe and analyse the most pertinent clinical and pathologic features of tracheal carcinomas as they relate to treatment and prognosis.

[Early detection of hearing loss in neonates by using transient evoked otoacoustic emissions]. / Detección precoz de hipoacusia en recién nacidos mediante otoemisiones acústicas evocadas transitorias.

OBJECTIVE: A precocious diagnosis of infantile deafness is essential to avoid its implications in the family and the social and employment future of those that suffer from them. The discovery of new tests that can be used for auditory screening, such as otoacoustic emission, has opened new perspectives in this field. PATIENTS AND METHODS: Universal screening was performed including neonates born in our area. We studied 7,153 children (296 with indicators of risk) born between 1995 and 1997. Our protocol was based on transient evoked otoacoustic emissions as the screening method and brainstem auditory evoked potentials as the diagnostic procedure. RESULTS: Two out of 1000 ears studied presented serious/deep deafness and 1.39 per 100 had some type of hearing loss. The incidence of pathology was higher among ears of children with risk factors: 1.8 per 100 had serious/deep deafness and 7.59 per 100 some type of hearing loss. CONCLUSIONS: Transient evoked otoacoustic emission is an effective method when used in infantile auditory screening, since it is objective, bloodless and quick. Its correlation with auditory evoked potentials is very high, which proves their reliability. The best moment to perform this test (OAE) is when the discharge from the hospital is certified. We believe that universal screening is necessary, although a much higher incidence of deafness is encountered among children with risk factors. The establishment of programs for the precocious detection of infantile deafness should not be delayed.

[Laryngeal paraganglioma]. / Paraganglioma laríngeo.

A case of laryngeal paraganglioma in a 65-year-old male was treated by supraglotic laryngectomy. This controversial tumor is analyzed and guidelines are given for its clinical and histological (immunohistochemical) diagnosis and treatment.

Portoenterostomy diversion. Experimental study in antireflux technique.

Ascending cholangitis was induced in dogs by performing a biliodigestive Roux-Y anastomosis. Then two valvular antireflux mechanisms were performed on separate groups of these dogs with the aim of preventing the onset of ascending cholangitis. One was performed by a laterolateral plicature at the intestinal anastomosis and the other by invagination of the mucosa in the nonworking loop that had been anastomosed to the bile duct. All the dogs underwent analytic tests over a period of 3 months and histopathologic tests at the end of the study period. Results showed cholangitis and pericholangitis in the liver biopsy specimens of the group with no antireflux valve, to a lesser degree in the group with laterolateral plicature, and almost none in the animals with the invaginated valve.