C2-streptavidin mediates the delivery of biotin-conjugated tumor suppressor protein p53 into tumor cells.

We have previously generated a recombinant C2-streptavidin fusion protein for the delivery of biotin-labeled molecules of low molecular weight into the cytosol of mammalian cells. A nontoxic moiety of Clostridium botulinum C2 toxin mediates the cellular uptake, whereas the streptavidin unit serves as a binding platform for biotin-labeled cargo molecules. In the present study, we used the C2-streptavidin transporter to introduce biotin-conjugated p53 protein into various mammalian cell lines. The p53 tumor suppressor protein is inactivated in many human cancers by multiple mechanisms and therefore the restoration of its activity in tumor cells is of great therapeutic interest. Recombinant p53 was expressed in insect cells and biotin-labeled. Biotin-p53 retained its specific high-affinity DNA-binding as revealed by gel-shift analysis. Successful conjugation of biotin-p53 to the C2-streptavidin transporter was monitored by an overlay blot technique and confirmed by real-time surface plasmon resonance, providing a KD-value in the low nM range. C2-streptavidin significantly enhanced the uptake of biotin-p53 into African Green Monkey (Vero) epithelial cells as shown by flow cytometry. Using cell fractionation, the cytosolic translocation of biotin-p53 was detected in Vero cells as well as in HeLa cervix carcinoma cells. In line with this finding, confocal microscopy displayed cytoplasmic staining of biotin-p53 in HeLa and HL60 leukemia cells. Internalized biotin-p53 partially colocalized with early endosomes, as confirmed by confocal microscopy. In conclusion, our results demonstrate the successful conjugation of biotin-p53 to C2-streptavidin and its subsequent receptor-mediated endocytosis into different human tumor cell lines.

Use of psychotropic drugs, systemic antihistamines and medications for cough in 6-year-old children: a survey in the Bas-Rhin Region, France.

PURPOSE: The use of drugs in France is among the highest in developed countries. Among them, psychotropic medication in children has always been a matter of concern. Furthermore, on the basis of concerns about safety and efficacy, international authorities have either advised against the use of cough and cold medication or considered such an action. This survey aims to assess the prevalence of use of psychotropic drugs, antihistamines and medications for cough as well as parents' knowledge about the drugs used in 2009. METHODS: The study is based on a representative sample of 6-year-old children who were in kindergarten in 2009. School physicians asked their parents to answer a standardized questionnaire. Data were collected about the child, his or her family, and the consumption of psychotropic drugs, antihistamines, and medications for cough in the past 12 months. The Anatomical Therapeutic Chemical (ATC) classification system was used to classify the drugs used. RESULTS: The data from 5707 children were analyzed. The proportion of children who consumed at least one psychotropic drug was 0.68% (ATC code N). Antihistamines for systemic use were by far the most frequently consumed drugs (ATC code R06), with a prevalence of 17.54%. The great majority of antihistamines for systemic use were meant to treat cough, not insomnia or agitation. CONCLUSION: The use of psychotropic drugs was low in 2009 in the French region of Bas-Rhin. The promotion of alternatives to antihistamines for systemic use to treat cough should nevertheless be strengthened.

Association between television in bedroom and adiposity throughout adolescence.

OBJECTIVE: The objective was to determine if having a television (TV) in the bedroom is associated with physical activity (PA), TV/video viewing, and adiposity throughout adolescence. RESEARCH METHODS AND PROCEDURES: Longitudinal data (September 2002 through June 2005) were analyzed of 379 initially 12-year-old French adolescents participating as controls in the Intervention Centered on Adolescents' Physical activity and Sedentary behavior (ICAPS). Presence of a TV set in the bedroom (TV(bedroom)) and leisure activities were obtained by questionnaire. There was annual assessment of BMI, waist circumference, and body fat by bioimpedance. RESULTS: In boys but not girls, baseline TV(bedroom) was associated with higher TV/video viewing over time [odds ratio (OR) of high TV/video = 1.87; 95% confidence interval, 1.2 to 2.8] and less no-sport club participation (OR = 0.59; 95% confidence interval, 0.35 to 1.0). Both boys and girls with baseline TV(bedroom) had lower reading time (p < 0.0001 in boys; p = 0.04 in girls), while PA did not differ according to TV(bedroom) for boys or for girls. For boys only, baseline TV(bedroom) was associated with higher BMI (mean BMI over time 20.5 +/- 0.5 vs. 19.0 +/- 0.5 kg/m(2); p = 0.001), waist circumference (70.9 +/- 0.9 vs. 67.2 +/- 0.8 cm; p < 0.001), and body fat (15.9 +/- 0.9% vs. 13.5 +/- 0.9%; p < 0.001), without interaction with time. These relationships remained significant after adjustment for socioeconomic status. TV/video viewing explained 26%, 42%, and 36% of the relationships of TV(bedroom) with BMI, waist circumference, and body fat, respectively, while addition of other leisure activities in the models only marginally reduced the effects. DISCUSSION: These results suggest the importance of keeping TV out of an adolescent's bedroom from an obesity prevention perspective but show gender differences.