Aim Of The Study: Urge incontinence is considered to be a dysfunctional pathology of social interest due to the psychological and relational implications of such disability, the elevated number of affected patients and the consequent treatment costs. We propose an innovative non-pharmacological and non-invasive care methodology: Frequency rhythmic electrical modulation system (F.R.
View Article and Find Full Text PDFHyaluronic acid (HA) derivatives have been developed to try to enhance rheological properties of this molecule to make it suitable for various medical applications. The main dermatological application of HA derivatives is the augmentation of soft tissues, via injection into the dermis. HA derivatives are indicated for the correction of cutaneous contour deficiencies of the skin, particularly in cases of ageing or degenerative lesions or to increase lips.
View Article and Find Full Text PDFJ Control Release
October 1998
The formulation of a new controlled delivery system, based on a novel type of matrix obtained by the chemical reaction carried out in an aqueous medium on a mixed physical gel of gellan and scleroglucan, is described in this paper. The preparation yielded a new co-crosslinked polysaccharide (CCP) hydrogel, bearing carboxylic groups, that showed a sustained release behaviour that can be modulated by means of calcium ions. For the characterization of CCP, diffusion experiments through the swelled hydrogel were carried out in different environmental conditions and the release from tablets prepared with CCP and a model drug was evaluated.
View Article and Find Full Text PDFThe simultaneous separation and determination of a mixture of hydrocarbons and organochlorine compounds was successfully carried out by using sorption chromatography on a two-step microcolumn of silica and aluminium oxide for their fractionation, and a dual detector system. In addition to the separation and identification of hydrocarbons and heterocompounds containing nitrogen, oxygen and sulphur atoms, separation and identification of chlorinated hydrocarbons (dichlorobenzenes, p-chlorotoluene, hexachlorobutadiene, 1,2,4-trichlorobenzene and 2-chloronaphthalene), pesticides (chlorpicrin, aldrin, lindane, alpha- and beta-benzene hexachloride (BHC), endrin, dieldrin, endosulphan, methoxychlor) and herbicides (propanil, dichlobenil, trifluralin, difolatan) were achieved in mixtures containing polychlorinated biphenyl, strobane and chlordane.
View Article and Find Full Text PDFThe chromatographic characteristics of 33 amino acids have been studied using soap thin-layer chromatography (TLC). The influence of the type of detergent, the organic solvent and the acid concentration in the eluent on the chromatographic behaviour of the amino acids was investigated. Many interesting separations that cannot be effected by ion-exchange TLC have been performed.
View Article and Find Full Text PDFEighteen water-soluble food dyes have been studied by chromatography on thin layers of anion-exchange (AG 1-X4, DEAE-cellulose, PAB-cellulose and chitosan) and cation-exchange (Dowex 50-X4, Rexyn 102 and humic acid) materials; layers of silanised silica gel impregnated with cationic or anionic detergent were also used. Fourteen of the dyes were separated, but the two orange and the two black dyes were not. Some applications of the techniques to commercial products are reported.
View Article and Find Full Text PDFThe chromatographic characteristics of several nucleic acid constituents and of 36 phenols have been investigated on mixed layers of powdered chitosan and microcrystalline cellulose, with water, water-methanol mixtures and aqueous salt solutions at different pH values at mobile phases. The behaviour of the phenols was strongly correlated with the form in which these compounds were present in solution and therefore with the pH of the eluent. Chitosan was more effective than PEI- and DEAE-cellulose as adsorbent in separating phenols.
View Article and Find Full Text PDFThe chromatographic behaviour of 48 alkaloids on cation exchangers with cellulose, paraffin and polystyrene matrices in both the acid and sodium salt forms has been investigated. Water-organic solvent mixtures, aqueous buffer solutions and organic and mineral acid solutions in both water and in aqueous-organic solvents have been used as eluents. The retention mechanisms of these compounds on alginic acid, Rexyn 102 (Hplus) and Dowex 50-X4 (Hplus) thin layers are discussed.
View Article and Find Full Text PDFThe chromatographic behaviour of 48 alkaloids has been studied on Bio-Rad AG 1-X4, Cellex D and microcrystalline cellulose, eluting with solutions of different pH but constant ionic strength (0.5). Many interesting separations were effected on both AG 1-X4 and Cellex D layers.
View Article and Find Full Text PDFThe chromatographic characteristics of 58 phenols on Rexyn 102 and Dowex 50-X4 thin layers in both the acidic and sodium salt forms have been studied, using elution with water, water-alcohol mixtures and aqueous salt solutions at different pH values. The influence of the percentage of alcohol, the pH and the ionic strength on the chromatographic behaviour of these phenols was investigated. The validity of the relationships among the RF values, the pH of the eluent and the pKa of the phenol has been verified on Dowex 50-X4 (Na+) thin layers.
View Article and Find Full Text PDF