Metronidazole thermogel improves retention and decreases permeation through the skin

ABSTRACT Metronidazole (MTZ) is widely used as the standard antibiotic for the treatment of rosacea and, more recently, is being used off label in Brazilian hospitals for the treatment of wounds. Following oral administration, minimal amounts of active agent reaches the skin and side effects are strongly induced. Consequently, MTZ is currently being applied topically in order to improve the therapeutic efficacy with reduced side effects, with Rozex(r) (RZ) (an MTZ gelled formulation) being the only marketed product. This study examined whether the use of MTZ 0.75% from thermogel formulations could improve drug retention and reduce dermal exposure compared to that by Rozex(r). Following a 21 h permeation study, the highest total amount of MTZ permeated through the rat healthy and disturbed skin was seen with Rozex(r), but similar to all formulations regardless of the skin condition. On the other hand, the amount retained in the epidermis/dermis was larger for thermogel formulations; at least 4 fold that of Rozex(r), when the stratum corneum was present as a barrier. In conclusion, thermogel formulations can be favorable alternatives to Rozex(r) for the topical application of MTZ with improved efficacy and reduced side effects.

Guava: phytochemical composition of a potential source of antioxidants for cosmetic and/or dermatological applications

ABSTRACT Guava (Psidium guajava L.) is a native fruit of the American tropics with commercial applications for its taste, flavor and aroma. Numerous pharmacological uses have been described for it, such as the antiseptic effect of its leaves, the use of the fresh fruit and tea from its leaves for the treatment of diarrhea, dysentery, diabetes mellitus, and others. However, considering its rich composition, the guava also is a potential source of antioxidants to be used in the development of new formulations for cosmetic and/or dermatological applications, the main focus of this research. Herein, we describe the study of the phytochemical composition and the antioxidant activity of a guava extract prepared with non-toxic solvents aiming its use at biological applications. High performance liquid chromatography and mass spectrometry were employed to identify the major components, while thermoanalytical measurements and hot stage microscopy were used to assess the chemical stability of guava fruit extract. The antioxidant activity was also evaluated assessing the SOD-like activity and ABTS free radical scavenger. The results show that the extract is a rich source of phenolic compounds, such as quercetin, kaempferol, schottenol, among many others. All of the components found in guava extract exhibit biological effects according to the literature data, mainly antioxidant properties.

Misnomers in dermatology: Time to change and update.

Most of the misnomers encountered in dermatology have arisen from lack of understanding of the underlying etiopathogenesis, histopathology and/or concepts. Some misnomers are due to imprecise translations from word of origin, etymological bungles and/or factual errors. It is very important for the residents and practitioners of dermatology to update and change the old misnomers with relevant names to avoid confusion and misunderstanding. In this article, we have listed all the misnomers in dermatology and suggested the appropriate names as indicated.

Dermatología cosmiátrica / Cosmiatric dermatology

Actualmente existe gran publicidad sobre los procedimientos médicos quirúrgicos con fines cosméticos, por lo cual se consideran de gran importancia los tratamientos cosmiátricos con bases científicas: sus indicaciones, efectos secundarios, así como el instrumental requerido para su adecuada práctica. Los cosmiatras son dermatólogos que se dedican especialmente al cuidado de la piel sana y enferma así como el manejo de aquellas afecciones que producen alteraciones estéticas. En este artículo se revisan aquellos procedimientos terapéuticos con fines estéticos de uso frecuente documentados en la literatura médica practicados por dermatólogos especialmente aquellos dedicados a la cosmiatría

Marcas cutáneas en recien nacidos / Birthmarks detected in newborns

Presentamos las marcas cutáneas detectadas en 750 recién nacidos durante los meses de mayo y junio de 1995 en el Hospital Materno Perinatal de Lima, Perú, comparando nuestros hallazgos con los de la literatura nacional e internacional

Terapéutica dermatológica 1995-1996: parte 1 / The therapeutics dermatological 1995-1996: aprt 1

Se revisa la literatura Internacional de Terapéutica Dermatológica correspondiente a los años 1995-1996, seleccionando un grupo de bibliografía que consideramos de interés

Superantígenos en dermatología / Superantigens in dermatological

Los superantígenos se definen como un grupo de proteinas virales y bacterianas con la capacidad de activar simultáneamente grandes números de células T. Se clasifican en endógenos y exógenos. Los superantígenos, a diferencia de los antígenos convencionales,no son procesados intracelularmente por las células presentadoras de antígeno; además, estos tienen la capacidad de unir cruzadamente a la molécula del complejo mayor de histocompatibilidad localizada en la superficie de la célula presentadora de antígeno y a los linfositos T que expresen receptores con segmentos específicos (Vß) en sus cadenas, lo cual con lleva a una activación policlonal de células T. A nivel de la piel se ha demostrado que los superantígenos son capaces de estimular a los queratinocitos haciéndolos capaces de actuar como células presentadoras de antígeno. Varias enfermedades han sido relacionadas a los efectos inmunológicos de los superantígenos,tales como la psoriasis,la dermatitis atópica y el síndrome de Kawasaki. En la presente revisíon se detallará el mecanismo de acción inmunológica de los superantígenos así como su implicación en diferentes patologías