Physicochemical stability of a new topical timolol 0.5% gel formulation for the treatment of infant hemangioma.

Infant hemangioma (IH) is the most common tumor in infants, which affects 5-10% of white children. It is a tumor of vascular origin that appears in the first months of life. The indication for the treatment of the IH is not approved in the datasheet of the product, however it has been used in the infant hemangioma by topical administration as an alternative to oral propranolol, avoiding the main problems of the oral route (bradycardia and hypotension). The objective of this work is to study the physical and chemical (HPLC stability indicating method) stability of a 0.5% timolol gel for topical application during 60 days (considering the stability limit as 90% of initial concentration of timolol maleate). The gel was prepared with a polyacrylic acid derivative and the physical stability of the system was studied by visual control, rheological and mechanical characterization. The studied formulation guarantees the correct dose administering and stability after 60 days stored at 25 ± 2 °C and light protected (tube of aluminum). We have developed an easy topical gel for the treatment of infant hemangioma with physical and chemical stability higher than those provided by the majority of hospitals.

Clinical, radiological, and molecular diagnosis of progressive fibrodysplasia ossificans.

BACKGROUND: Progressive fibrodysplasia ossificans is a rare genetic disease with heterozygous mutations (autosomal dominant inheritance) in the ACVR1 gene, which causes progressive heterotopic ossification in muscles, tendons, and ligaments, usually secondary to trauma. The ossification foci generate pain, joint ankyloses, and restricted movement. Congenital shortening and medial deviation first metatarsal of the foot is a distinctive feature. This report aimed to present an educational value case of a patient with clinical, imaging, and molecular diagnosis of progressive fibrodysplasia ossificans, recognized as a rare condition that severely affects the quality of life. CASE REPORT: We present the case of a 6-year-old female patient with lumps in the right scapular and dorsal region, progressive joint rigidity, and short first metatarsal medially deviated since birth. By imaging studies, we established the diagnosis of progressive fibrodysplasia ossificans. Sanger sequencing of ACVR1 reported c.617G>A (p.Arg206His). CONCLUSIONS: Confirmation of the diagnosis allowed genetic counseling, including a comprehensive explanation of the disease's natural history and measures to prevent its rapid progression.

Novel aqueous chitosan-based dispersions as efficient drug delivery systems for topical use. Rheological, textural and release studies.

The use of a novel cross-linked thiolated chitosan (CTS) was investigated as the main component of aqueous dispersions (at 1% and 3% w/v) for topical drug delivery systems. The nonionic theophiline (Th) and the cationic diltiazem(.)HCl (Dt) (at 0.5% w/v concentration) were used as model drugs. All aqueous dispersions behaved as viscoelastic fluids. The CTS 1% dispersions showed predominance of viscous component and low viscosity. However, in the CTS 3% dispersions, both the elastic component and high viscosities prevailed. So, texture parameters improved from CTS 1% to 3% dispersions and CTS 3%-Dt showed greater cohesion and adhesion than CTS 3%-Th, but always below CTS alone. All dispersions showed a Fickian diffusion mechanism. Despite release profiles of both drugs almost fully overlapped at 1% CTS, diffusion coefficients confirmed Dt released faster than Th at 3% CTS. The rheological behavior and the chemical nature of the drugs explained these results.

Clinical, radiological, and molecular diagnosis of progressive fibrodysplasia ossificans / Diagnóstico clínico, radiológico y molecular de fibrodisplasia osificante progresiva

Abstract Background: Progressive fibrodysplasia ossificans is a rare genetic disease with heterozygous mutations (autosomal dominant inheritance) in the ACVR1 gene, which causes progressive heterotopic ossification in muscles, tendons, and ligaments, usually secondary to trauma. The ossification foci generate pain, joint ankyloses, and restricted movement. Congenital shortening and medial deviation first metatarsal of the foot is a distinctive feature. This report aimed to present an educational value case of a patient with clinical, imaging, and molecular diagnosis of progressive fibrodysplasia ossificans, recognized as a rare condition that severely affects the quality of life. Case report: We present the case of a 6-year-old female patient with lumps in the right scapular and dorsal region, progressive joint rigidity, and short first metatarsal medially deviated since birth. By imaging studies, we established the diagnosis of progressive fibrodysplasia ossificans. Sanger sequencing of ACVR1 reported c.617G>A (p.Arg206His). Conclusions: Confirmation of the diagnosis allowed genetic counseling, including a comprehensive explanation of the disease’s natural history and measures to prevent its rapid progression.

Resumen Introducción: La fibrodisplasia osificante progresiva es una enfermedad genética poco frecuente, causada por variantes patogénicas en estado heterocigoto (herencia autosómica dominante) en el gen ACVR1, que provoca osificación heterotópica progresiva en músculos, tendones y ligamentos, comúnmente secundaria a traumatismos. Los focos de osificación generan dolor, anquilosis articular y restricción del movimiento. Es característico el acortamiento congénito y la desviación medial del primer metatarsiano del pie. El objetivo de este reporte es presentar un caso de alto valor educativo de una paciente con diagnóstico clínico, imagenológico y molecular de fibrodisplasia osificante progresiva, reconocida como una condición infrecuente y que afecta de manera grave la calidad de vida. Caso clínico: Paciente de sexo femenino con tumoraciones induradas en la región dorsal y escapular, detectadas a los 6 años de vida. Cursaba además con rigidez articular progresiva y primer metatarsiano del pie acortado y con desviación en sentido medial desde el nacimiento. Por estudios de imagen se estableció el diagnóstico de fibrodisplasia osificante progresiva. Por secuenciación Sanger se reportó c.617G>A (p.Arg206His) en ACVR1. Conclusiones: La confirmación del diagnóstico permitió ofrecer un asesoramiento genético integral, incluyendo una amplia explicación de la evolución natural del padecimiento y de las medidas preventivas para disminuir su rápida progresión.

Protection by alpha-tocopherol against skin necrosis induced by doxorubicin hydrochloride.

Extravasation of doxorubicin hydrochloride during i.v. infusions can cause serious local complications due to the action of free radicals which are produced as a result of this leakage. An experiment was carried out using female Wistar rats to study the protective effect of alpha-tocopherol against the tissular necrosis produced by 0.05 mg of doxorubicin hydrochloride. alpha-Tocopherol was administered by two vehicles, one emulsified and the other gelled, with butylated hydroxytoluene and ascorbic acid used as antioxidants, respectively. No differences were observed in the diameters of the ulcers with each treatment in the various groups of animals relative to the control group. Conversely, differences were found (p < 0.05) in the period of chronic lesion between the animals treated with alpha-tocopherol and those used as a control group, irrespective of the vehicle used. These results lead to the conclusion that accidental toxicity resulting from the leakage of doxorubicin hydrochloride in the skin can be mitigated by applying alpha-tocopherol topically, due to its regenerating action in the damaged cutaneous zones. This effect is independent of the vehicle used and also of the antioxidant employed in the elaboration of the formulas.

[Disseminated candidiasis in parenteral drug addicts. Report of 15 cases]. / Candidiasis diseminada en adictos a drogas por vía parenteral. Presentación de 15 casos.

Fungic infections related to parenteral use of drugs increased significantly from 1980 on with the description of the disseminated candidiasis syndrome. Associated to the administration of brown heroin, this syndrome is characterized by the development of cutaneous, ocular and osteoarticular infections, isolated or combined, by Candidas albicans. We present 15 patients with disseminated candidiasis: 12 developed ocular affection (10 endophthalmitis and 2 chorioretinitis): 9, cutaneous lesions and 3 osteoarticular affection (3 costochondritis and one hip arthritis); 8 presented simultaneous infections in several locations. The biopsy and culture of the cutaneous lesions was the most profitable test in order to establish the microbiological diagnosis. We comment on the main etiopathogenetic, clinical, diagnostic and therapeutic aspects of the disseminated candidiasis syndrome.

Determination of alpha-tocopherol in semisolid gelled preparations by reversed phase HPLC.

Recently there has been increasing interest in alpha-tocopherol due to the possibility of its acting as a chemoprotective agent for skin cancer since it acts to protect dermic cells from the attack of free radicals caused by ionized radiations or chemical substances. To carry out this study, semisolid preparations were made from this active substance. We demonstrate a rapid, sensitive and reproducible method of extraction and analysis using an HPLC system with ultraviolet detection to carry out routine measurements beginning with hydrophilic gels of alpha-tocopherol.

Synthesis and characterization of a novel chitosan-N-acetyl-homocysteine thiolactone polymer using MES buffer.

We report a new "green" approach to synthesize a novel thiolated chitosan conjugate, chitosan-N-acetyl-homocysteine thiolactone (chitosan-AcHcys) using a "Good's buffers", 2-(N-morpholino)ethanesulfonic acid (MES). After that, the crosslinked Xr-chitosan-AcHcys was obtained only in the presence of air, without other reactants. The chitosan-AcHcys spectrum shows a partial incorporation of the thiolactone onto the polymer backbone. The derivative thermogravimetric analysis confirmed that chitosan-AcHcys is slightly less stable than starting chitosan; however, the peak profile is broadened which is indicative of deeper changes in the thermal degradation process. Also, aqueous dispersions with different concentrations of the crosslinked material (Xr-chitosan-AcHcys) were prepared and rheologically characterized. All aqueous dispersions are viscoelastic fluid with shear-thinning behavior. The viscosity of the dispersions (1-7% of chitosan-AcHcys) increases as a function of polymer concentration. So, we have achieved to disperse a high concentration of thiolated-chitosan derivative in water with different rheological characteristics, which could affect the drug release.

Improved semiconductor lattice parameters and band gaps from a middle-range screened hybrid exchange functional.

We show that the middle-range exchange-correlation hybrid of Henderson, Izmaylov, Scuseria and Savin (HISS) performs extremely well for elemental and binary semiconductors with narrow or visible spectrum band gaps, as well as some wider gap or more ionic systems used in devices. The lattice parameters are superior to those predicted by the screened hybrid functional of Heyd, Scuseria and Ernzerhof (HSE), and provide a significant improvement over the geometries predicted by typical semilocal functionals, yielding results competitive with PBEsol, which was specially tuned for solids. HISS also yields band gaps superior to those produced by functionals developed specifically for the solid state. Timings indicate that HISS is more computationally efficient than HSE, implying that the high quality lattice constants coupled with improved optical band gap predictions render HISS a useful adjunct to HSE in the modeling of geometry-sensitive semiconductors.

A study of the spread surface of polymeric dispersions of Eudragit.

The rheology of non-Newtonian fluid systems is complex. Their experimental study is difficult because of the existence of many dependent variables. In the present work, a mathematical equation is proposed to calculate the spread surface from a simple viscosimetric study in a theoretical way. It was determined for multiple parameters. The spread surface has to be marked because of its direct relation to the shear stress; this fact enabled us to connect one variable dependent on the compression deformation with another dependent on the shear deformation. At the same time, the viscoelastic phenomenon can be evidenced by applying this mathematical equation.