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Single Topical Application (single + topical_application)
Selected AbstractsAssessment of carcinogenic potential of repeated fish fried oil in miceMOLECULAR CARCINOGENESIS, Issue 10 2006Manoj K. Pandey Abstract Our prior studies have shown that single topical treatment of repeated fish fried oil extract (RFFE), containing various polycyclic aromatic hydrocarbons (PAHs), to the dorsal epidermis of mice caused enhancement of DNA damage along with higher expression of p53 and p21WAF1 proteins and cell-cycle arrest. In the present study carcinogenic potential of repeated fish fried oil (RFFO) and RFFE was assessed. Single topical application of RFFO (100 µL/animal) and RFFE (100,500 µg/animal) to Swiss albino female mice resulted in significant induction (1.8- to 7.4-fold) of ornithine decarboxylase activity. Twice weekly topical application of methylcholanthrene (MCA) for 24 wk or single topical application of 7,12-dimethylbenzanthracene (DMBA) or RFFO or RFFE, as initiator followed by twice weekly application of 12-O-tetradecanoyl phorbol myristate acetate (TPA) as promoter for 24 wk, resulted in development of skin papillomas after 6, 7, 18, and 9 wk, respectively. The cumulative number of tumors in MCA, DMBA/TPA, RFFE (200 µg)/TPA, and RFFE (500 µg)/TPA groups were 276, 168, 34, and 58 after 24 wk while negligible or minimal initiating activity was noticed in RFFO/TPA group. No tumors were found in animals either given twice weekly topical application of RFFO or a single initiating dose of DMBA followed by twice weekly application of RFFO. Histopathology of skin of animals treated with RFFE/TPA showed marked proliferation of epidermal layers along with abnormal mitosis and multinucleated tumor appearance. Skin of animals in groups RFFO/TPA and DMBA/RFFO showed sloughing and regeneration of epidermal layers, oedema along with proliferation of fibroblasts. Histochemical localization of ,-glutamyl transpeptidase was found to be substantially higher in skin of mice treated with RFFO/TPA and RFFE/TPA. Animals treated with RFFO/TPA, DMBA/RFFO, and RFFE/TPA resulted in significant induction of cutaneous aryl hydrocarbon hydroxylase (AHH) (421,432%), ethoxyresorufin-O-deethylase (252,316%), and glutathione S-transferase (133,245%) activities. Animals treated with RFFO/TPA, DMBA/RFFO, and RFFE/TPA led to significant reduction in glutathione content (39,44%) with a concomitant increase in lipid peroxidation (254,492%). Animals treated with RFFO/TPA and RFFE/TPA led a significant decrease in catalase (43,69%) and superoxide dismutase (20,31%) activities while glutathione reductase activity was found to be diminished (23,51%) in RFFO, RFFO/TPA, DMBA/RFFO, and RFFE/TPA treated groups. These results suggest that RFFE possess skin tumor initiating activity and that it may have weak promoting activity as well, which may involve free radicals. © 2006 Wiley-Liss, Inc. [source] High-Level Transient Production of a Heterologous Protein in Plants by Optimizing Induction of a Chemically Inducible Viral Amplicon Expression SystemBIOTECHNOLOGY PROGRESS, Issue 6 2007Michael A. Plesha We have demonstrated that the method of chemical induction using a chemically inducible viral amplicon expression system can be optimized to increase expression of a heterologous protein in plants. A cucumber mosaic virus inducible viral amplicon (CMViva) expression system was used to transiently produce a recombinant human blood protein, ,-1-antitrypsin (AAT), by co-infiltrating intact and detached Nicotiana benthamiana leaves with two Agrobacterium tumefaciens strains, one containing the CMViva expression cassette carrying the AAT gene and the other containing a binary vector carrying the gene silencing suppressor p19. Infiltrated plants were induced by either topical applications or pressure injections and inducer was applied at either a single or multiple time points. Applying induction solution every 2 days via topical application resulted in increasing maximum levels of biologically functional rAAT from 0.71% to 1.3% of the total soluble protein (TSP) in detached plant leaves, a 1.8-fold improvement. Multiple applications of induction solution via pressure injection into intact leaves resulted in maximum levels of biologically functional rAAT being elevated 3-fold up to 2.4% of TSP compared to 0.8% of TSP when using the conventional method of a single topical application, and expression levels remained high 6 days post-induction. Overall production of rAAT in intact leaves was found to have a maximum level of 5.8% of TSP or 390 mg rAAT per kg leaf tissue when applying multiple injections of chemical induction solution. [source] Use of povidone,iodine during the first trimester of pregnancy: a correct practice?BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 3 2009I Velasco Povidone,iodine (PVP-I) has been widely used as an antiseptic agent during invasive procedures for prenatal diagnosis. Women have been reported of thyroid dysfunction after simple exposure to PVP-I. We studied the effect on thyroid function and urinary iodine excretion after a single topical application of PVP-I in 31 women who had a miscarriage during the first trimester of pregnancy. PVP-I is absorbed through the skin and the vaginal mucosa, resulting in a sudden increase in the urinary excretion of iodine and a short-term variation in concentrations of thyroid hormones in maternal serum. This metabolic effect could have consequences for the embryo and the fetus during crucial stages of development. [source] Lipoteichoic acid from Staphylococcus aureus enhances allergen-specific immunoglobulin E production in miceCLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2003K. Matsui Summary Background Our previous study demonstrated that lipoteichoic acid (LTA) from Staphylococcus aureus induced T helper type 2 (Th2)-prone dermatitis resembling that seen in atopic dermatitis (AD) patients in mice sensitized percutaneously with an allergen. However, the effects of LTA on allergen-specific IgE production in such sensitized mice have not been elucidated. Objective The purpose of this study was to determine the effects of LTA from S. aureus on allergen-specific IgE production in mice sensitized percutaneously with a house dust mite antigen (MA). Methods Mice were sensitized with a single topical application of MA and/or LTA to barrier-disrupted abdominal skin. One to 5 weeks later, MA-specific IgE antibodies in sera from sensitized mice were detected by an enzyme-linked immunosorbent assay (ELISA). Expression of B7.1 (CD80), B7.2 (CD86) and CD40L molecules by CD40-positive (CD40+) and CD4-positive (CD4+) cells in the lymph nodes of sensitized mice were analysed by flow-cytometry (FACS). Results Simultaneous sensitization with MA and LTA increased IgE production 3 weeks later, significantly more than sensitization with MA alone. FACS analysis of CD40+ cells in the lymph nodes from sensitized mice showed that simultaneous sensitization with MA and LTA did not enhance CD80- or CD86-expression by antigen-presenting cells such as B lymphocytes and dendritic cells more than sensitization with MA alone. However, analysis of CD4+ cells in the lymph nodes showed that simultaneous sensitization with MA and LTA increased the number of CD40L-expressing Th cells more than sensitization with MA alone. Conclusion These results suggest that LTA enhances allergen-specific IgE production by a mechanism associated with up-regulation of CD40L-expressing Th cells and this might explain the role of skin colonization with S. aureus in AD patients. [source] | ||||||||||