71 research outputs found
IBOPAMINE d-1 dopaminergic agonist in the physiopathology of intraocular pressure
No full textIbopamine as eyedrops, following adminis-tration in the conjunctival sac, is readily hy-drolysed to epinine, a dopamine analogue, by the esterases present in the aqueous hu¬mour and in the ocular tissues. lbopamine stimulates a-adrenergic recep¬tors and D-l dopaminergic receptors at ocu¬lar level. The non-cycloplegic mydriatic effect of ibopamine is due to an a-adrenergic stimu¬lation, while the D-l dopaminergic activity determines an increase in aqueous humour production. lbopamine induces a marked short-term non-cycloplegic mydriasis, lacking both top¬ical and systemic undesireble side-effects, , which enables its use in the diagnostic exam-ination of the ocular fundus, particularly in the newborn and pediatric patients. lbopamine may be employed to substitute phenylephrine in the association with tropi¬camide and/ or cyclopentolate; moreover it proves to be effective as a mydriatic prior to and after surgical procedures. The D-l dopaminergic activity of ibopamine represents the more interesting property of the drug under different aspects: in the diag¬nosis of glaucoma, in the treatment of ocular hypotony and in studies on the physiopathol¬ogy of the intraocular pressure. Several clin¬ical investigations confirmed the usefulness of ibopamine in the diagnostic iter of glau¬coma as a pharmacological test to evaluate the functionality of the outflow pathways of the aqueous humour. The test is simple to perform; positive in 92% of patients suffer¬ing from open-angle glaucoma, while it is negative in the healthy eye. lts use is recom¬mended in relatives of glaucomatous pa¬tients. The increase in aqueous humour production induced by ibopamine proves to be very use¬ful in the treatment of ocular hypotony fol¬lowing vitreo-retinal or antiglaucomatous filtering surgery and in the treatment in chronic hypotony secondary to long-lasting uveitis
Improved method for determination of waxes in olive oils: reduction of silica and use of a less hazardous solvent
No full textThe evaluation of the content of waxes is request both by IOC Trade Standard and by Regulation (EEC) 2568/91 and its further amendments. The official method uses 15 g of silicic acid and elutes several fractions by using huge volumes of dangerous solvent (n-hexane). The developed method uses 1 g of silicic acid with a different particle size and less than 20 mL of solvent mixture, substituting n-hexane with less toxic isooctane. Briefly, after spiking with a suitable internal standard, oil sample is fractionated by SPE (Solid Phase Extraction) cartridge with 1 g of silica, waxes are eluted with 14 mL of isooctane/ethyl ether 99/1 (6 mL discarded and 8 mL collected), then, after elution sample is reconstitute in 200 μL of n-heptane and analysed by capillary GC. Data of “In home” validation, (repeatability, accuracy and recovery) and relative chromatograms are reported in this paper
Adrenergic and Adrenolytic drugs:vascular activity on ciliary body vessels in rabbits.
No full textAdrenergic and Adrenolytic drugs:vascular activity on ciliary body vessels in rabbits
Increase in aqueous humor production following D1 receptors activation by means of ibopamine
No full textBackground: Topically administered 2% ibopamine (a dopaminergic agonist) induces a transitory ocular hypertension in 92% of patients with primary open-angle glaucoma and in 52% of patients with normal tension glaucoma. In normal eyes, ibopamine has no effect on IOP. Purpose: The aim of the present study was to verify, by means of fluorophotometric techniques, which hydrodynamic changes could be induced in normal and glaucomatous eyes, stimulating the D1 receptor with 2% ibopamine administered topically. In addiction, we wanted to evaluate if ibopamine could modify IOP before and after an experimentally induced outflow system impairment in rabbits. Methods: In study 1 we performed a measurement of aqueous humor flow in 6 healthy volunteers and in 6 glaucomatous patients, before and after 2% ibopamine administration. In study 2 the alteration of outflow pathways was induced by means of Laminaria Digitata in 10 rabbits. Results: After 2% ibopamine administration we found a significant increase in aqueous humor production, both in glaucomatous (P = 0.035) and normal eyes (P = 0.004). In rabbits, we found no significant change in IOP at basal conditions. After experimentally induced outflow system impairment by laminaria, we observed a marked increase in IOP (+ 13.5 mmHg SD 7.2; P < = 0.001) following ibopamine administration. Conclusions: These experimental data have a diagnostic value in glaucoma, since they show how an intraocular hypertensive response due to ibopamine in normotensive eyes is a sign of initial outflow impairment, Moreover, the possibility to increase the aqueous humor production sets new trends in the treatment of post surgical ocular hypotony
The potentialities of the Anatomage Table for head and neck pathology: medical education and informed consent
No full textA further polymorphism of the Gd locus for glucose-6-phosphate dehydrogenase present among blacks (Nigerians) and apparently absent among caucasoids: The quantitative isoelectrophoretic variation of the Gd+ allele
No full textA structural but isoelectrophoretic moderate variation of glucose-6-phosphate dehydrogenase (G6PD) activity is common among Nigerians (a black population exposed to a long-lasting intense Plasmodium falciparum malarial endemia). It had never even been searched for among Caucasoids and Mongoloids. In the present work, we attempted to ascertain whether this polymorphism exists among Caucasoids. With this purpose, two Caucasoid male populations were studied: Sardinians and Romans, who respectively did and did not experience an evolutionarily effective exposure to P. falciparum. The approach adopted here consisted in comparing the variations of G6PD activity observed between brothers who certainly received their Gd gene from the same grandparent (hence Gd genes identical by descent) with those between brothers who received it (in the Roman series) or may have received it (in the Sardinian series) from different grandparents. No evidence for common moderate G6PD activity variations segregating with the Gd gene was found either in Romans or Sardinians, who have both been studied with much larger samples and more sensitive approaches than those which detected such type of polymorphism among Nigerians. The upper 95% confidence limit of such zero estimates for the frequency of the isoelectrophoretic quantitative Gd variant alleles were about 0.04 and 0.025 for Romans and Sardinians, respectively. This is the first example of a genetic region (the Gd gene with its flanking sequences) apparently monomorphic in a major race and with several (four) polymorphic sites in another major race
Recycling Hydrocarbon Cuts into FCC Units
No full textA bench scale reactor, which is a simulator of FCC riser units, has been used to study the upgrading of low value hydrocarbon cuts (a heavy coker naphtha and a visbreaker naphtha) by catalytic cracking of a mixture of these cuts (20 wt %) with the conventional feedstock (vacuum gas oil). The results of yield and composition of gasoline have been compared with those obtained by catalytic cracking of vacuum gas oil and with those obtained following other upgrading strategies for these cuts, such as their direct catalytic cracking or their blending with the gasoline stream of the FCCU. In general terms, increases in gasoline yields oppose to losses of its quality. The results show that the cracking of the heavy paraffins contained in these naphthas is inhibited by the adsorption of heavy olefins present in these cuts. Coke yields are not higher than the ones obtained when cracking standard VGO, and then the impact on units' heat balances would be negligible.Fil: Fernandez, M. L.. Universidad del País Vasco; EspañaFil: Lacalle, Ainhoa. Universidad del País Vasco; EspañaFil: Bilbao, Javier. Universidad del País Vasco; EspañaFil: Arandes, J. M.. Universidad del País Vasco; EspañaFil: de la Puente, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin
Orden y moralidad en los discursos periodísticos: la valoración del «otro» en la región santafesina (1880-1915)
No full textEn aquest article analitzem els termes « progrés » i « ordre » que van ser centrals a l'hora de construir l'Estat Nacional argentí. La premsa santafesina produïda entre 1880 i 1915 va gaudir de certa singularitat al valorar l '«altre social» a la regió, i en identificar especialment quines conductes amenaçaven la construcció provincial en els espais urbans. A través dels diaris conservats a l'Arxiu General de la Província de Santa Fe, descrivim la reconfiguració de l'ordre social, les concepcions morals de l'ordre i la redefinició de la violènciaIn this paper we analyze the concepts of progress and order that were central in building the argentine National State. The journalism produced in Santa Fe between 1880 and 1915, had certain uniqueness in assessing the “social other” in the region, and especially in identifying what behaviors threatened the provincial construction in urban areas. Through the papers preserved in the General Archive of the Province of Santa Fe, we describe the reconfiguration of social order, moral conceptions of order and redefining violenceEn este artículo analizamos los términos «progreso» y «orden» que fueron centrales a la hora de construir el Estado Nacional argentino. La prensa santafesina producida entre 1880 y 1915 gozó de cierta singularidad al valorar al «otro social» en la región, y al identificar especialmente qué conductas amenazaban la construcción provincial en los espacios urbanos. A través de los periódicos conservados en el Archivo General de la Provincia de Santa Fe, describimos la reconfiguración del orden social, las concepciones morales del orden y la redefinición de la violenci
Preparation, characterization, and dye removal study of activated carbon prepared from palm kernel shell
No full textPalm oil mill wastes (palm kernel shell (PKS)) were used to prepare activated carbons, which were tested in the removal of colorants from water. The adsorbents were prepared by 1-h impregnation of PKS with ZnCl2 as the activating agent (PKS:ZnCl2 mass ratios of 1:1 and 2:1), followed by carbonization in autogenous atmosphere at 500 and 550 °C during 1 h. The characterization of the activated carbons included textural properties (porosity), surface chemistry (functional groups), and surface morphology. The dye removal performance of the different activated carbons was investigated by means of the uptake of methylene blue (MB) in solutions with various initial concentrations (25–400 mg/L of MB) at 30 °C, using a 0.05-g carbon/50-mL solution relationship. The sample prepared with 1:1 PKS:ZnCl2 and carbonized at 550 °C showed the highest MB adsorption capacity (maximum uptake at the equilibrium, qmax = 225.3 mg MB / g adsorbent), resulting from its elevated specific surface area (BET, 1058 m2/g) and microporosity (micropore surface area, 721 m2/g). The kinetic experiments showed that removals over 90% of the equilibrium adsorptions were achieved after 4-h contact time in all the cases. The study showed that palm oil mill waste biomass could be used in the preparation of adsorbents efficient in the removal of colorants in wastewaters.Fil: García, Juan Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Zaini, Muhammad Abbas Ahmad. Universiti Teknologi Malaysia; MalasiaFil: Zakaria, Zainul Akmar. Universiti Teknologi Malaysia; Malasi
Rhéologie et rhéometrie des bétons: Application aux bétons autonivelants
No full textBecause knowledge of the flow properties of concrete has become essential with the advent of fluid concretes, the LCPC has developed the BTRHEOM concrete rheometer. In this work, we carried out a critical analysis of the first version of the device and improved it. The BTRHEOM has proved to be a good tool for detecting faults in concrete formulations. In a final section, we verified that the models are relevant for self-levelling concretes, the spread of which can then be predicted satisfactorily. A complete metrology system has also been developed to characterise these materials in greater detail: the BRTHEOM has been adapted to measure their flow properties in a confined environment, their resistance to blocking has been quantified using the L-box test and segregation has been measured on split specimens (the development of a rapid segregation test on fresh concrete, based on measuring the penetration of a ball into the concrete, proved disappointing). Thanks to an analysis based on granular concepts, we are able to propose prediction models for all these properties, as well as a rational and practical approach to formulating self-levelling concretes, which now needs to be validated more widely.Parce que la connaissance des propriétés d’écoulement des bétons est devenue primordiale avec l’avènement des bétons fluides, le LCPC a développé le rhéomètre à béton BTRHEOM. Nous avons procédé dans ce travail à une analyse critique de la première version de l’appareil et à son amélioration. Le BTRHEOM s’avère alors être un bon outil de détection des défauts de formulation des bétons. Nous avons, dans une dernière partie, vérifié que les modèles sont pertinents pour les bétons autonivelants dont on peut alors prédire l’étalement de façon satisfaisante. Une métrologie complète a également été développée pour caractériser plus finement ces matériaux : le BRTHEOM a été adapté pour mesurer leurs propriétés d’écoulement en milieu confiné, leur résistance au blocage a été quantifiée par l’essai de boite en L et la ségrégation a été mesurée sur éprouvette fendue (le développement d’un essai rapide de ségrégation sur béton frais, basé sur la mesure de l’enfoncement d’une bille dans le béton s’est avéré décevant). Grâce à une analyse basée sur des concepts granulaires, nous proposons des modèles de prévision de l’ensemble de ces propriétés ainsi qu’une démarche rationnelle et pratique de formulation des bétons autonivelants qui doit maintenant être validée plus largement
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