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The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers  相似文献   
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Human papillomavirus (HPV) vaccine effectiveness may differ between settings. Here we present the first real-world effectiveness study of HPV vaccination on high-grade cervical lesions from Norway, among women who received HPV vaccine outside the routine program. We performed an observational study of all Norwegian women born 1975 to 1996 and retrieved individual data from nationwide registries on HPV vaccination status and incidence of histologically verified high-grade cervical neoplasia during 2006 to 2016. We estimated the incidence rate ratio (IRR) and 95% confidence intervals (CI) for vaccination vs no vaccination by Poisson regression stratified by age at vaccination <20 years and ≥20 years. The cohort consisted of 832 732 women, of which 46 381 (5.6%) received at least one dose of HPV vaccine by the end of 2016. The incidence rate of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) increased with age regardless of vaccination status and was highest at age 25 to 29, at 637/100 000 among unvaccinated women, 487/100 000 among women vaccinated before age 20 and 831/100 000 among women vaccinated at age 20 or older. The adjusted IRR of CIN2+ between vaccinated and unvaccinated women was 0.62 (95% CI: 0.46-0.84) for women vaccinated below age 20, and 1.22 (95% CI: 1.03-1.43) for women vaccinated at age 20 or older. These findings indicate that HPV vaccination among women too old to be eligible for routine HPV vaccination is effective among women who are vaccinated below age 20 but may not have the desired impact among women who are vaccinated at age 20 or older.  相似文献   
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ObjectiveTo assess the evolution of cost per patient/year and the cost per patient/year/drug in patients with rheumatoid arthritis (RA) receiving biological treatments. To analyze and quantify the factors influencing this evolution, such as the optimization of the biological drugs, the use of biosimilars, and official discounts and discounts obtained after negotiated procedures. In addition, to assess specific clinical parameters of disease activity in these patients.MethodsRetrospective, observational study conducted in a Spanish tertiary hospital. Adult patients diagnosed with RA under treatment from 2009 to 2017 were included.Results320, 270 and 389 patients were included in 2009, 2013 and 2017, respectively. The patient/year cost decreased from 10,789€ in 2009, 7491€ in 2013 to 7116€ in 2017. In 2017, due to the established competition, discounts of 14% and 29.5% were achieved on etanercept and its biosimilar; 11.5%, 17.8%, 17.9%, 17.3% on adalimumab, certolizumab, golimumab and tocilizumab IV respectively, and 24.6% and 43.1% on infliximab and its biosimilar. The percentage of patients optimized in 2017 was 35.2%. The annual saving in 2017 was 1,288,535€ (830,000€ due to dose optimization and/or administration regimens, 249,666€ corresponding to 7.5% of the official discount and 208,868€ after negotiated procedures).ConclusionThe annual cost per patient in RA decreased considerably due to different factors, such as discounts on the purchase of drugs due to official discounts and negotiated procedures, together with the optimization of therapies, the latter being the factor that contributed most to this decrease.  相似文献   
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