Stain retention and surface characteristics of posterior composites polished by one-step systems

PURPOSE: To compare susceptibility to stain of three posterior composite surfaces polished with two one-step polishing systems, to test the efficiency of the re-polishing to remove the stain formed and to analyze the polished surfaces by SEM. METHODS: The resin composites tested were Clearfil Photo Posterior, SureFil and Filtek P60. The polishing systems used were Sof-Lex Brush and PoGo. Twenty-two discs of each material were fabricated and divided into two treatment groups of 11. Out of the latter, six were used for SEM evaluation for surface morphology and five for stain retention testing. The discs were roughened with silicon paper and polished for 30 seconds with each system. Specimens were immersed in coffee and distilled water for 7 days. Color measurements were made at baseline and after 1, 3, 5, and 7 days with a spectrophotometer. The specimens were then re-polished with the same systems and their colors re-measured. All comparison of color change and re-polishing were subjected to repeated measures ANOVA with a Bonferroni post hoc test (P < or = 0.05). RESULTS: After 1 week, the coffee stained all the resin composites. Clearfil Photo Posterior was the least stained composite while Filtek P60 was the most. Regardless of the materials, PoGo polishing was less susceptible to staining (P < or = 0.05). The color change could be partially removed with re-polishing. The surfaces of Sof-Lex Brush polished samples, except the Clearfil group, were scratched and thus more susceptible to stain retention.     

Stem Cell Sciences plc

Stem Cell Sciences' core objective is to develop safe and effective stem cell-based therapies for currently incurable diseases. In order to achieve this goal, Stem Cell Sciences recognizes the need for multiple technologies and a globally integrated stem cell initiative. The key challenges for the successful application of stem cells in the clinic is the need for a reproducible supply of pure, fully characterized stem cells that have been grown in suitable conditions for use in the clinic.     

In vitro cytotoxic activity and structure activity relationships of iridoid glucosides derived from Veronica species

This study was an investigation of the cytotoxic activity of iridoid glucosides, including aucubin, catalpol, 6‐O‐acetylcatalpol, veronicoside, catalposide, verproside, amphicoside, veratroylcatalposide, verminoside, aquaticosides B and C isolated from different Veronica species. The cytotoxic activity was determined against Hep‐2 (human epidermoid carcinoma), RD (human rhabdomyosarcoma), L‐20B (transgenic murine L‐cells) cancer cell lines and Vero (African green monkey kidney cells) non‐cancerous cell line using the MTT method. While verminoside, amphicoside and veronicoside were found to exhibit cytotoxic activity in the concentration range of 70–355 µ m , acetylcatalpol, aquaticosides B and C, catalposide, veratroylcatalposide and verproside showed cytostatic activity. Apoptotic cell death was observed as the effect of verminoside in the histological analysis of the tested cell lines. In conclusion, iridoid glucosides are considered to show a biphasic effect on cancer cells that is both cytostatic and cytotoxic, depending on the chemical structure and the type of cancer cell. Copyright © 2011 John Wiley & Sons, Ltd.     

Do knowledge of, perception of, and attitudes toward epilepsy affect the quality of life of Turkish children with epilepsy and their parents?

The main goal of this study was to evaluate knowledge of, perceptions of, and attitudes toward epilepsy and then to correlate knowledge with quality of life and stigmatization of children with epilepsy and their families. Specific questionnaires were administered to children aged 8 to 17 with epilepsy (n=220) and their parents (n=313). Poor school performance, less social support, less self-esteem, higher anxiety, greater stigmatization, and more depressive symptoms were documented in children who were less knowledgeable (P<0.05). Parents were found to be more knowledgeable about the antiepileptic drugs used, understanding both the effects and the side effects of the medications (P<0.05). Family activities were less restricted if they were more knowledgeable and these parents reported worrying less about their children (P<0.05). Knowledge about epilepsy is associated with less perceived stigmatization and social isolation, as well as fewer depressive symptoms and misperceptions.     

The risk factors for infections acquired by cerebral hemorrhage and cerebral infarct patients in a neurology intensive care unit in Turkey

Few studies have investigated the risk factors for nosocomial infections developed in neurology intensive care units (ICUs). In this study, the risk factors for ICU-acquired infections in patients with cerebral hemorrhage and cerebral infarct who were treated for more than 24 h at the Ankara Training and Research Hospital were prospectively evaluated over a study period of 14 months. Of 171 patients included in the study, 71 (41.5%) were found to have acquired 163 infections in the ICU unit throughout 1,867 patient days. The rate of infection per 100 patients admitted was 95.3, and per 1,000 patient days, 87.3. The most common nosocomial infections were urinary tract infection (42.9%), pneumonia (27%) and primary bacteremia (19%). Multivariate logistic regression analysis revealed age > or = 70 (P < 0.05), the presence of a central venous catheter (P=0.004), and parenteral nutrition (P=0.02) as ICU-acquired infection risk factors. The presence of infection on admission was identified as a factor decreasing the risk of ICU-acquired infection (P < 0.001). The high infection rates found in this study may be due to lack of full compliance to infection control measures. In conclusion, each type of ICU has its own epidemiological findings for nosocomial infections and thus needs to determine the risk factors using periodical surveillance studies to guide control measures.     

Methicillin-resistant Staphylococcus aureus on hospital admission in Turkey

A total of 900 patients were screened for methicillin-resistant Staphylococcus aureus (MRSA) on hospital admission, and 11 MRSA strains (1.2%) were detected. All 11 MRSA strains were positive for the mecA and PVL genes. Eight of the 11 MRSA-positive patients (72%) had a history of hospitalization within the previous 12 months.     

Pneumothorax as an initial manifestation of obstructive sleep apnea syndrome

Case report  

A sixty-five-year-old man with bullous lung disease was admitted to emergency service with chest pain and dyspnea that developed during sleep. Pneumothorax was diagnosed both clinically and radiologically. After the chest drainage, the patient presented with a prolonged air leak that required thoracotomy. Further history and occurrence of pneumothorax during sleep suggested that obstructive sleep apnea might play a role in the development of pneumothorax. Nocturnal polysomnography later confirmed the diagnosis of severe obstructive sleep apnea syndrome.