Influence of local tetracycline on the microbiota of alveolar osteitis in rats

The aim of the present study was to evaluate the effects of local tetracycline on the occurrence of alveolar osteitis in rats, and on the microbiota associated to this infection. Forty Wistar rats were randomly assigned to 4 groups (n=10): I - the rats had the maxillary right incisor extracted and the alveolar wound did not receive any treatment; II - adrenaline and Ringer-PRAS were introduced into the alveolar wound; III - the alveolar wound was irrigated with sterile saline; and IV - the alveolar wound was irrigated with an aqueous solution of tetracycline. Microbial samples from the alveolar wounds were collected 2 days after surgery and inoculated on blood agar (with and without 8 microg/mL of tetracycline) and other selective media, and were incubated in either aerobiosis or anaerobiosis at 37 masculineC, for 2 to 14 days. It was verified that tetracycline reduced the occurrence of alveolar osteitis in the rats and caused significant changes in the microbiota of the surgical sites, decreasing the number of anaerobes and increasing the participation of tetracycline-resistant and multi-resistant microorganisms.     

Color stability evaluation of aesthetic restorative materials

Color match is one of the most important characteristics of aesthetic restorative materials. Maintenance of color throughout the functional lifetime of restorations is important for the durability of treatment. This characteristic is not constant among dental materials. The purpose of this research was to assess the color stability of five aesthetic restorative materials when immersed in a coffee solution. Seventy-one 17 mm x 1 mm specimens, divided into five groups, were made using one direct composite resin (Tetric Ceram, Ivoclar/Vivadent - G1), three indirect composite resins (Targis, Ivoclar/Vivadent - G2; Resilab Master, Wilcos - G3; belleGlass HP, Kerr - G4) and one porcelain (IPS Empress 2, Ivoclar/Vivadent - G5). The specimens were immersed in a coffee staining media for 15 days and stored under a controlled temperature of 37 degrees C +/- 1 degrees C in the dark. The evaluations were made after 1, 7 and 15 days by means of reflectance spectrophotometry. The data was submitted to two-way ANOVA (p < 0.005) and post hoc tests. Statistical difference was observed between G1 / G3 and the other groups; G2 / G4 and the other groups; and G5 and all the other groups. It was concluded that G1 and G3 showed significantly higher discoloration than the other groups. G2 and G4 showed intermediary pigmentation, while G5 showed the smallest changes.     

E6 and E7 proteins from different beta-papillomaviruses types do not interfere in UVB-induced apoptosis of HaCaT keratinocytes

Beta-papillomaviruses (beta-HPV) have been linked to the development of skin cancer in humans. Because both E6 and E7 proteins from beta-HPV have been involved in the potential carcinogenicity of these viruses, we investigated their role on UVB-induced apoptosis in HaCaT cell line. HaCaT cells have been transduced with both E6/E7 using a retroviral system and treated with PRIMA-1. Apoptosis was assessed by flow cytometry to measure mitochondrial membrane potential and DNA fragmentation. HaCat keratinocytes transduced with both E6 and E7 genes of seven beta-HPV types (HPV5, HPV8, HPV14, HPV24, HPV36, HPV38 and HPV49) did not demonstrate any inhibition of UVB-induced apoptosis, even after p53 reactivation through PRIMA-1. Our data suggest that the expression of E6 and E7 exert different modulatory effects on UVB-induced apoptosis according to beta-HPV types and to the cellular genetic context.     

Retinoblastoma and deletion of the long arm of chromosome 13: An underestimated diagnosis?

We report an infant with normal neurological development and phenotype who developed bilateral retinoblastoma (RB). This patient, despite lack of dysmorphic features, demonstrated constitutional abnormality of the long arm of chromosome 13 on standard karyotype. We recommend systematic cytogenetic examinations complemented by fluorescent in situ hybridization as second-line screening in all patients suspected for hereditary RB despite negative RB1 molecular screening and normal phenotype.     

Towards risk stratification in systemic atherosclerosis: value of myocardial function and viability imaging as an adjunct to MR angiography

Objectives

To longitudinally assess the value of cardiac functional and viability imaging as a supplement to MR angiography in patients with atherosclerotic disease.

Methods

Cardiac MRI was performed in 195 consecutive patients with symptomatic peripheral arterial disease. Of these, 186 patients were followed for 22?±?5 months for the presence of cardiac events (cardiac death, acute coronary syndrome and hospitalisation as a result of congestive heart failure).

Results

Myocardial viability imaging showed a high prevalence of known (n?=?31) and occult myocardial infarctions (MI) (n?=?26). Cardiac events occurred more often in patients with reduced ventricular function (ejection fraction (EF) less than 40%, cardiac event in 4/8 patients; EF 40–55%, cardiac event in 10/40 patients; EF greater than 55%, cardiac event in 15/138 patients) as well as in patients with occult MI (8/25 patients) and known MI (11/30 patients). In patients with normal function, the detection of a previous MI was of high relevance to prognosis.

Conclusions

Both reduced EF and the presence of MI influence patients’ prognoses. Performing cardiac MRI in this patient population may influence further patient management including intensified risk factor intervention.     

Polymorphisms in the UBC9 and PIAS3 genes of the SUMO-conjugating system and breast cancer risk

SUMOylation consists in the covalent conjugation of small ubiquitin-related modifiers to target proteins. SUMOylation participates in processes that are tightly linked to tumorigenesis, and genetic variability in the SUMO-conjugating system may influence the development of breast cancer. We recently reported that variation in the UBC9 gene encoding the SUMO-conjugating enzyme may affect the grade of breast tumors. Following comprehensive in silico analyses for detection of putative functional polymorphisms in 14 genes of the SUMO system, we selected one coding SNP in PIAS3 and seven tag SNPs in UBC9 for association analyses. Results were based on 1,021 cases, and 1,015 matched controls from the population-based GENICA study. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by conditional logistic regression. To explore the association with polymorphisms closely linked to the genotyped variants, multiple imputation based on HapMap data was applied. The study revealed associations of four UBC9 polymorphisms with risk of grade 1 tumors. Comparison of genotype and haplotype models indicated that the best representation of risk solely relied on rs7187167 under dominant penetrance. Women carrying the rare allele showed an increased risk of grade 1 tumors compared with common homozygotes (OR 1.87, 95% CI 1.18–2.95). This effect appeared to be stronger in women with a family history of breast or ovarian cancer. Imputation of polymorphisms in a 300-kb region around the genotyped polymorphisms identified no variants with stronger associations. Our findings suggest that genetic variation in UBC9 may affect the risk of grade 1 breast tumors.