Genome-wide screening of mouse knockouts reveals novel genes required for normal integumentary and oculocutaneous structure and function.

Oculocutaneous syndromes are often due to mutations in single genes. In some cases, mouse models for these diseases exist in spontaneously occurring mutations, or in mice resulting from forward mutatagenesis screens. Here we present novel genes that may be causative for oculocutaneous disease in humans, discovered as part of a genome-wide screen of knockout-mice in a targeted single-gene deletion project. The International Mouse Phenotyping Consortium (IMPC) database (data release 10.0) was interrogated for all mouse strains with integument abnormalities, which were then cross-referenced individually to identify knockouts with concomitant ocular abnormalities attributed to the same targeted gene deletion. The search yielded 307 knockout strains from unique genes with integument abnormalities, 226 of which have not been previously associated with oculocutaneous conditions. Of the 307 knockout strains with integument abnormalities, 52 were determined to have ocular changes attributed to the targeted deletion, 35 of which represent novel oculocutaneous genes. Some examples of various integument abnormalities are shown, as well as two examples of knockout strains with oculocutaneous phenotypes. Each of the novel genes provided here are potentially relevant to the pathophysiology of human integumentary, or oculocutaneous conditions, such as albinism, phakomatoses, or other multi-system syndromes. The novel genes reported here may implicate molecular pathways relevant to these human diseases and may contribute to the discovery of novel therapeutic targets.

Active ingredients, mechanisms of action and efficacy tests of antipollution cosmetic and personal care products

Urban population around the globe is direct exposed to the pollution caused by several sources (vehicles, industries, smokes etc.) and primary pollutants are divided in particulate matter and toxic gases. Current researches in populous countries indicated that exposure to pollution could affect sebum composition, stratum corneum quality and signs of skin aging. Hair and scalp are also affected by the excessive exposure to pollutants, resulting in a dull, dry and lifeless appearance. Cosmetics have been evolved conceptual and scientifically to achieve substantial effectiveness against pollution damaging on the cutaneous tissue, involving the development of innovative multipurpose active ingredients and efficacy tests, skilled to prove the protection and benefits of such personal care products. In this review, we highlighted the skin and hair/scalp damages provoked by the main environmental pollutants and the active substances used in antipollution cosmetics/personal care products with the respective mechanisms of action. Likewise, in vitro and in vivo efficacy tests were discussed concerning the antipollution claim substantiating

Evaluation of the in vitro Activity of Dermaseptin 01, a CationicAntimicrobial Peptide, against Schistosoma mansoni

Schistosomiasis is a neglected tropical disease that remains a considerable public health problem worldwide. Since the mainstay of schistosomiasis control is chemotherapy with a single drug,praziquantel, drug resistance is a concern. Here, we examined the in vitro effects of dermaseptin 01(DS 01), an antimicrobial peptide found in the skin secretion of frogs of the genus Phyllomedusa, onSchistosoma mansoni adult worms. DS 01 at a concentration of 100 mg/ml reduced the worm motor activity and caused the death of all worms within 48 h in RPMI 1640 medium. At the highest sublethal concentration of antimicrobial peptide (75 mg/ml), a 100% reduction in egg output of paired female worms was observed. Additionally, DS 01 induced morphological alterations on the tegument of S. mansoni, and a quantitative analysis carried out by confocal microscopy revealed extensive destruction of the tubercles in a dose-dependent manner over the concentration range of 50 –200 mg/ml. It was the first time that an anthelmintic activity towards schistosomes has been reported for a dermaseptin.

Soft epidermis of a scaleless snake lacks beta-keratin.

Beta-keratins are responsible for the mechanical resistance of scales in reptiles. In a scaleless crotalus snake (Crotalus atrox), large areas of the skin are completely devoid of scales, and the skin appears delicate and wrinkled. The epidermis of this snake has been assessed for the presence of beta-keratin by immunocytochemistry and immunoblotting using an antibody against chicken scale beta-keratin. This antibody recognizes beta-keratins in normal snake scales with molecular weights of 15-18 kDa and isoelectric points at 6.8, 7.5, 8.3 and 9.4. This indicates that beta-keratins of the stratum corneum are mainly basic proteins, so may interact with cytokeratins of the epidermis, most of which appear acidic (isoelectric points 4.5-5.5). A beta-layer and beta-keratin immunoreactivity are completely absent in moults of the scaleless mutant, and the corneous layer comprises a multi-layered alpha-layer covered by a flat oberhautchen. In conclusion, the present study shows that a lack of beta-keratins is correlated with the loss of scales and mechanical protection in the skin of this mutant snake.