31 research outputs found

    Effect of double thermal and electrochemical oxidation on titanium alloys for medical applications

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    The research focuses on the development and characterization of innovative thin hybrid oxide coatings obtained in subsequent processes of thermal (TO) and electrochemical (EO) oxidation. Four different surface modifications were investigated and the microstructure was determined, the mechanical, chemical and biological properties of the Ti-13Nb-13Zr alloy were assessed using scanning electron microscopy, X-ray dispersion analysis, glow discharge emission spectroscopy, Raman spectroscopy, nanoindentation and corrosion resistance measurements. The composite layers were evaluated for antimicrobial activity, cytotoxicity bioassays and wettability tests were performed. The conducted studies of two-stage oxidation (TO + EO) have shown that it is possible to obtain layers with a different structure - crystalline and nanotubular. The formation of a nanotube layer on the surface of the crystalline layer is dependent on the thickness of the crystalline layer. The produced double titanium oxide coatings show high surface roughness, high corrosion resistance, are hydrophilic, slightly antibacterial, and not cytotoxic, which has a huge impact on the process of connecting the tissue with the implant

    The global retinoblastoma outcome study : a prospective, cluster-based analysis of 4064 patients from 149 countries

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    DATA SHARING : The study data will become available online once all analyses are complete.BACKGROUND : Retinoblastoma is the most common intraocular cancer worldwide. There is some evidence to suggest that major differences exist in treatment outcomes for children with retinoblastoma from different regions, but these differences have not been assessed on a global scale. We aimed to report 3-year outcomes for children with retinoblastoma globally and to investigate factors associated with survival. METHODS : We did a prospective cluster-based analysis of treatment-naive patients with retinoblastoma who were diagnosed between Jan 1, 2017, and Dec 31, 2017, then treated and followed up for 3 years. Patients were recruited from 260 specialised treatment centres worldwide. Data were obtained from participating centres on primary and additional treatments, duration of follow-up, metastasis, eye globe salvage, and survival outcome. We analysed time to death and time to enucleation with Cox regression models. FINDINGS : The cohort included 4064 children from 149 countries. The median age at diagnosis was 23·2 months (IQR 11·0–36·5). Extraocular tumour spread (cT4 of the cTNMH classification) at diagnosis was reported in five (0·8%) of 636 children from high-income countries, 55 (5·4%) of 1027 children from upper-middle-income countries, 342 (19·7%) of 1738 children from lower-middle-income countries, and 196 (42·9%) of 457 children from low-income countries. Enucleation surgery was available for all children and intravenous chemotherapy was available for 4014 (98·8%) of 4064 children. The 3-year survival rate was 99·5% (95% CI 98·8–100·0) for children from high-income countries, 91·2% (89·5–93·0) for children from upper-middle-income countries, 80·3% (78·3–82·3) for children from lower-middle-income countries, and 57·3% (52·1-63·0) for children from low-income countries. On analysis, independent factors for worse survival were residence in low-income countries compared to high-income countries (hazard ratio 16·67; 95% CI 4·76–50·00), cT4 advanced tumour compared to cT1 (8·98; 4·44–18·18), and older age at diagnosis in children up to 3 years (1·38 per year; 1·23–1·56). For children aged 3–7 years, the mortality risk decreased slightly (p=0·0104 for the change in slope). INTERPRETATION : This study, estimated to include approximately half of all new retinoblastoma cases worldwide in 2017, shows profound inequity in survival of children depending on the national income level of their country of residence. In high-income countries, death from retinoblastoma is rare, whereas in low-income countries estimated 3-year survival is just over 50%. Although essential treatments are available in nearly all countries, early diagnosis and treatment in low-income countries are key to improving survival outcomes.The Queen Elizabeth Diamond Jubilee Trust and the Wellcome Trust.https://www.thelancet.com/journals/langlo/homeam2023Paediatrics and Child Healt

    Concentrations Of Norfloxacin In Prostatic Tissues Following Oral Administration In Patients With Benign Prostatic Hyperplasia

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    For assessing plasma and tissue concentrations of norfloxacin after oral administration, twelve patients with benign prostatic hypertrophy (BPH) were given two doses of 400 mg norfloxacin approximately 12 hours apart prior to transurethral resection of the prostate (TURP). Prostatic tissue samples and blood samples were collected and assayed for norfloxacin content by HPLC. The mean peak norfloxacin concentration in plasma was 1.63 μg/ml (range 0.63 to 3.38 μg/ml). The mean peak concentration in prostatic tissue was 1.63 μg/g (range 0.75 to 3.30 μg/g). The plasma and prostatic tissue levels of norfloxacin exceeded the MIC's of most urinary tract pathogens. The data suggest that norfloxacin may be useful in the treatment of chronic bacterial prostatitis. © 1988 Akadémiai Kiadó.201474
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