Objective To evaluate the anti-microbial effects of photodynamic therapy (PDT) on infected human teeth ex vivo. Materials and Methods Fifty-two freshly extracted teeth with pulpal necrosis and associated periradicular radiolucencies were obtained from 34 subjects. Twenty-six teeth with 49 canals received chemomechanical debridement (CMD) with 6% NaOCl and twenty-six teeth with 52 canals received CMD plus PDT. For PDT, root canal systems were incubated with methylene blue (MB) at concentration of 50 µg/ml for 5 minutes followed by exposure to red light at 665 nm with an energy fluence of 30 J/cm2. The contents of root canals were sampled by flushing the canals at baseline and following CMD alone or CMD+PDT and were serially diluted and cultured on blood agar. Survival fractions were calculated by counting colony-forming units (CFU). Partial characterization of root canal species at baseline and following CMD alone or CMD+PDT was performed using DNA probes to a panel of 39 endodontic species in the checkerboard assay. Results The Mantel-Haenszel chi-square test for treatment effects demonstrated the better performance of CMD+PDT over CMD (P=0.026). CMD+PDT significantly reduced the frequency of positive canals relative to CMD alone (P=0.0003). Following CMD+PDT, 45 of 52 canals (86.5%) had no CFU as compared to 24 of 49 canals (49%) treated with CMD (canal flush samples). The CFU reductions were similar when teeth or canals were treated as independent entities. Post-treatment detection levels for all species were markedly lower for canals treated by CMD+PDT than were for those treated by CMD alone. Bacterial species within dentinal tubules were detected in 17/22 (77.3%) and 15/29 (51.7%) of canals in the CMD and CMD+PDT group, respectively (P= 0.034). Conclusion Data indicate that PDT significantly reduces residual bacteria within the root canal system, and that PDT, if further enhanced by technical improvements, holds substantial promise as an adjunct to CMD.

Background Event related desynchronization (ERD) of mu waves, or mu suppression, over sensorimotor cortex has been observed in response to self-generated movement, viewing movement, or imaging movement. Mu suppression is especially pronounced when the movement has social relevance and is being generated by a biological entity indicating successful social adaptation. And since social adaptation problems are common in schizophrenia, the authors designed a study to test mu wave suppression in a first episode of psychosis population. Methods A total of 32 subjects (first episode of psychosis patients N=20; healthy comparison subjects N=12) aged 13–34 watched movement videos with and without socially relevant cues, executed by biological or non-biological agents. Scalp electrode EEG recordings of mu rhythm (8–13Hz) over sensorimotor cortex during the session were used to calculate mu wave suppression. Average mu suppression was compared within and between groups, as well as correlations between mu suppression and clinical measures. Results First episode patients showed significantly reduced mu wave suppression over sensorimotor cortex when viewing biological motion, compared to healthy subjects. In addition, negative symptom burden and poor social adjustment correlated with impaired mu wave suppression. Conclusions Our finding provides the first description of impaired event related desynchronization of mu waves in response to biological motion and its correlation with negative symptoms and social adjustment in the first episode of psychosis. Future studies can be conducted to determine if mu wave suppression represents an endophenotype with potential applications in biological treatments of negative symptoms and social functioning deficits in schizophrenia.

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The recently published crystal structure of the external domains of ␣V␤3 confirms the prediction that the aminoterminal portion of ␣V, which shares 40% homology with ␣IIb, folds into a ␤-propeller structure and that the 4 calcium-binding domains are positioned on the bottom of the propeller. To gain insight into the role of the calcium-binding domains in ␣IIb biogenesis, we characterized mutations in the second and third calcium-binding domains of ␣IIb in 2 patients with Glanzmann thrombasthenia. One patient inherited a Val298Phe mutation in the second domain, and the other patient inherited an Ile374Thr mutation in the third domain. Mammalian cell expression studies were performed with normal and mutant ␣IIb and ␤3 cDNA constructs. By flow cytometry, expression of ␣IIb Val298Phe/␤3 in transfected cells was 28% of control, and expression of ␣IIbIle374Thr/␤3 was 11% of control. Pulse-chase analyses showed that both mutant pro-␣IIb subunits are retained in the endoplasmic reticulum and degraded. Mutagenesis studies of the Val298 and Ile374 residues showed that these highly conserved, branchchained hydrophobic residues are essential at these positions and that biogenesis and expression of ␣IIb␤3 is dramatically affected by structural variations in these regions of the calcium-binding domains. Energy calculations derived from a new model of the ␣IIb ␤-propeller indicate that these mutations interfere with calcium binding. These data suggest that the ␣IIb calcium-binding domains play a key structural role in the ␤-propeller, and that the structural integrity of the calcium-binding domains is critical for integrin biogen-