The Ability of Dental Practitioners to Light-Cure Simulated Restorations.

OBJECTIVES: To determine the ability of dental professionals to deliver a radiant exposure of at least six J/cm2 in 10 seconds to simulated restorations. METHODS AND MATERIALS: The study initially examined 113 light-emitting-diode (LED) light polymerization units (LPUs) used in dental offices to determine if they could deliver at least 6 J/cm2 radiant exposure (RE) in 10s. This assessment was completed by using a laboratory-grade light measuring device (checkMARC, BlueLight Analytics, Halifax, NS, Canada). The participating dental professionals whose LPUs could deliver 6 J/cm2 then used their own LPU to light-cure simulated anterior and posterior restorations in the MARC Patient Simulator (BlueLight Analytics). They then received specific instructions and were retested using the same LPUs. Data were statistically analyzed with a series of one-way analysis of variance (ANOVA), two-way ANOVA, paired-samples t-tests, Fisher post hoc multiple comparison tests, and McNemar tests with a preset alpha of 0.05 (SPSS Inc). RESULTS: Ten (8.8%) LPUs could not deliver the required RE to the checkMARC in 10s and were eliminated from the study. For the anterior restoration, most dental practitioners (87.3%) could deliver at least 6 J/cm2 before instructions. After receiving additional light-curing instructions, only two (1.9%) participants were unable to deliver 6 J/cm2 to the anterior location. At the posterior location, only 55.3% (57) participants could deliver at least 6 J/cm2 before the instructions. After receiving these instructions, an additional 32 participants delivered at least 6 J/cm2. Overall, after receiving instructions on how to use the LPU correctly, the participants improved the amount of RE they delivered to anterior and posterior restorations by 22.5% and 30%, respectively. CONCLUSION: This study revealed that at the baseline, 44.7% of participating dental professionals failed to deliver 6 J/cm2 in 10s to the posterior simulated restoration when using their own LPU.

Interference effect between superparamagnetic and spin glass correlated moments in a system of dispersed Co(3)O(4) nanocrystallites.

An inhomogeneous system of aggregates of Co(3)O(4) nanocrystallites dispersed in an amorphous SiO(2) matrix has been studied. X-ray diffraction and atomic force microscopy reveal a bimodal distribution of crystallite sizes, smaller nanocrystallites with dimension below 10 nm and larger nanocrystallites of about 20 nm. The Co(3)O(4) nanocrystallites enter the composition of nanograins with dimension 20-60 nm. The nanograins build aggregates with dimension 200-500 nm. A large value of the effective magnetic moment per Co(2+) ion obtained from the high-temperature susceptibility measurements indicates possible disturbance of the normal spinel structure in which a fraction of Co(3+) ions also possesses magnetic moment. An analysis based on the temperature dependence of the coercive field has shown that the smaller nanocrystallites behave as superparamagnetic particles with a blocking temperature of about 10 K. Simultaneous existence of two relaxation processes is observed in the frequency dependence of the imaginary part of the ac magnetic susceptibility in the vicinity of T = 15.8 K. The temperature dependence of the width of the distribution function of relaxation times obtained from the Cole-Cole diagrams exhibits behaviour characteristic for spin glass dynamics in a temperature range above 17.6 K and is temperature independent below 15.8 K, which is a property of superparamagnetic particles. The variation of the width of the distribution function between 17.6 and 15.8 K indicates that interference of the superparamagnetic and spin glass dynamics occurs. It has been found that average relaxation time increases with decreasing temperature from τ(c)<10(-4) s at 17.6 K to 1.5 × 10(-1) s at 15 K. The increase of the average relaxation time with decreasing temperature, the observed blocking temperature of the superparamagnetic moments at about 10 K and interference appearing between the two spin dynamics suggest that the magnetic moments in the smaller as well as in the larger nanocrystallites are subject to a thermally activated blocking process at low temperatures.

Integrin-linked kinase, a promising cancer therapeutic target: biochemical and biological properties.

Integrin-linked kinase (ILK) is an ankyrin repeat-containing Ser/Thr kinase that interacts with the cytoplasmic domains of beta(1) and beta(3) integrins. ILK is widely expressed in tissues throughout the body, and, as might be expected, appears to mediate a diversity of functions relating to its role in coupling integrins and growth factor receptors to downstream signaling pathways. Through its downstream targets protein kinase B/Akt and glycogen synthase kinase-3beta, ILK appears to be involved in several oncogenesis-related events, including suppression of apoptosis and promotion of cell survival, as well as cell migration and invasion. Over-expression of ILK in epithelial cells results in anchorage-independent cell growth with increased cell cycle progression. Inoculation of nude mice with ILK over-expressing cells leads to tumor formation. Furthermore, increased ILK expression and activity have been correlated with malignancy in several human tumor types, including breast, prostate, brain, and colon carcinomas. Based on these findings, ILK represents an excellent therapeutic target for the prevention of tumor progression. Here, we provide an overview of the physical and biochemical properties of ILK, and present data describing the impact of small-molecule ILK inhibitors on several ILK-mediated cellular functions.

Choroid plexus connexin 43 expression and gap junction flexibility are associated with clinical features of acute EAE.

Experimental autoimmune encephalomyelitis (EAE) induced by ventricular injection of antimyelin oligodendrocyte antibodies in DA rats showed severe clinical signs 4 to 5 days after injection. Immunocytochemically, connexin 43 (Cx43) expression increased in the choroid plexus and in the subventricular and subgranular zones of the hippocampus during the development of acute EAE, and decreased after the beginning of the remission phase of the disease. Quantitative computing analysis showed a significantly increased Cx43 expression in the choroid plexus at the peak of the disease. Plaque-pattern expression of the Cx43 in the choroid plexus (CP) of acute EAE correlated with the increased docking and coupling of the Cx43 hemichannels revealed by atomic force microscopy (AFM). The inner diameter of the gap junction (GJ) channels decreased in the CP of acute EAE, measured by AFM. Cell structure conformational changes showed influences the channels' flexibility in acute EAE.

The role of partial cystectomy in treatment of muscle invasive bladder cancer.

Muscle invasive bladder cancer is usually treated by radical cystectomy, but in some selected cases with solitary tumor with appropriate localization partial cystectomy can be the treatment of choice achieving long term results with bladder preservation. We reviewed records of 11 patients which were treated in 5 year period from June 2002 to June 2007. by partial cystectomy according to the size of the tumor, localization, histology, multifocality, pathological and clinical stage, sex, and age. Male:female ratio was 6:5, mean age of the patients being 64.9 years. All patients bur one had solitary lesions located in the bladder dome in 4, on lateral sides in 5,2 patients had a tumor in diverticulum. TCC gr II was diagnosed 6 pts, TCC gr III in 5. One patient died in a year from disease progression, one from other reason, while all other patients are alive and disease free, the longest disease free interval being 3 years. Bladder capacity is adequate in all patients resulting in good quality of life . Our results suggest that in selected patients cancer control can be achieved with partial cystectomy.