What's special about personally familiar faces? A multimodal approach

Dual-route models of face recognition suggest separate cognitive and affective routes. The predictions of these models were assessed in recognition tasks with unfamiliar, famous, and personally familiar faces. Whereas larger autonomic responses were only triggered for personally familiar faces, priming effects in reaction times to these faces, presumably reflecting cognitive recognition processes, were equal to those of famous faces. Activation of stored structural representations of familiar faces (face recognition units) was assessed by recording the N250r component in event-related brain potentials. Face recognition unit activation increased from unfamiliar over famous to personally familiar faces, suggesting that there are stronger representations for personally familiar than for famous faces. Because the topographies of the N250r for personally and famous faces were indistinguishable, a similar network of face recognition units can be assumed for both types of faces.     

First comprehensively documented case of Paracoccus yeei infection in a human

Paracoccus yeei was isolated in pure culture from an aerobic blood culture and bulla fluid from a 67-year-old male. The biochemical identification scheme for this recently described species is outlined. Because of its reaction pattern it is not unlikely that P. yeei is underdiagnosed.     

Tritrichomonas foetus induces apoptotic cell death in bovine vaginal epithelial cells

Tritrichomonas foetus is a serious veterinary pathogen, causing bovine trichomoniasis, a sexually transmitted disease leading to infertility and abortion. T. foetus infects the mucosal surfaces of the reproductive tract. Infection with T. foetus leads to apoptotic cell death of bovine vaginal epithelial cells (BVECs) in culture. An affinity-purified cysteine protease (CP) fraction yielding on sodium dodecyl sulfate-polyacrylamide gel electrophoresis a single band with an apparent molecular mass of 30 kDa (CP30) also induces BVEC apoptosis. Treatment of CP30 with the protease inhibitors TLCK (Nalpha-p-tosyl-l-lysine chloromethyl ketone) and E-64 [l-trans-epoxysuccinyl-leucylamide-(4-guanido)-butane] greatly reduces induction of BVEC apoptosis. Matrix-assisted laser desorption ionization-time-of-flight MALDI-TOF mass spectrometry analysis of CP30 reveals a single peak with a molecular mass of 23.7 kDa. Mass spectral peptide sequence analysis of proteolytically digested CP30 reveals homologies to a previously reported cDNA clone, CP8 (D. J. Mallinson, J. Livingstone, K. M. Appleton, S. J. Lees, G. H. Coombs, and M. J. North, Microbiology 141:3077-3085, 1995). Induction of apoptosis is highly species specific, since the related human parasite Trichomonas vaginalis and associated purified CPs did not induce BVEC death. Fluorescence microscopy along with the Cell Death Detection ELISA(PLUS) assay and flow cytometry analyses were used to detect apoptotic nuclear condensation, DNA fragmentation, and changes in plasma membrane asymmetry in host cells undergoing apoptosis in response to T. foetus infection or incubation with CP30. Additionally, the activation of caspase-3 and inhibition of cell death by caspase inhibitors indicates that caspases are involved in BVEC apoptosis. These results imply that apoptosis is involved in the pathogenesis of T. foetus infection in vivo, which may have important implications for therapeutic interference with host cell death that could alter the course of the pathology in vivo.     

Smoking cessation in patients diagnosed with head and neck cancer

OBJECTIVE: To determine patients' smoking status after the diagnosis and treatment of squamous cell carcinoma of the head and neck (SCCHN) and to identify factors associated with smoking cessation. DESIGN: Cross-sectional survey study conducted over a 2-year period. SETTING: Head and neck surgery clinic of an academic tertiary care hospital. METHODS: Two hundred thirteen consecutive patients diagnosed with SCCHN were interviewed to ascertain patients' smoking status and the incidence of smoking cessation. Information on demographics, tobacco and alcohol history, disease characteristics, and treatment modality was also collected. MAIN OUTCOME MEASURES: The rate of smoking cessation was evaluated, in which smoking cessation is defined as the use of no cigarettes at least 1 month prior to the interview. Possible predictors of smoking cessation were evaluated. RESULTS: One hundred twenty-five patients were found to be smoking at the time of diagnosis. Among these patients, 53.6% stopped smoking after diagnosis or during treatment. In the univariate analyses, tumour site (p = .01), concurrent alcohol use (p = .03), and number of attempts to quit pre- (p = .03) and postdiagnosis (p = .001) were found to be highly predictive of patient smoking cessation. Multivariable modelling showed that gender, tumour site, and number of attempts to quit smoking were significantly and independently related to smoking cessation. CONCLUSIONS: Although smoking cessation would be presumed to be high after cancer diagnosis, this study has identified patient subgroups in which postdiagnosis smoking cessation intervention programs need to be made more effective.     

Face repetition effects in direct and indirect tasks: an event-related brain potentials study

We investigated immediate repetition effects on event-related potentials (ERPs) during direct and indirect tasks for sequentially presented face pairs. The first face (F1) was presented masked or unmasked, and at different stimulus onset asynchronies (SOAs, 67 vs. 1000 ms) preceding the second face (F2). Experiment I (indirect task) required a semantic classification of F2, with F1 identity being irrelevant. Experiment II (direct task) used the same stimulus sequence but required a physical identity matching of F1 and F2. Whereas no masked repetition effects in behaviour or ERPs were seen, such effects were clearly shown for unmasked F1 faces. For short SOAs, an early-onset ( approximately 100 ms) occipital repetition effect, an inferior temporal N250r (200-300 ms) and a central-parietal N400 modulation (300-500 ms) were seen in both tasks, whereas a parietal P600 effect (500-800 ms) was only present in the indirect task. For long SOAs, the early occipital effect disappeared, suggesting that it reflects a fast decaying iconic memory trace. Clear task differences were seen for N250r, N400, and P600 modulations: P600 was larger for the indirect task, and may be a correlate of semantic analysis required by this task. By contrast, N250r and N400 were larger for the direct task, suggesting that these components are sensitive to task relevance and/or attentional focus to F1, and thus do not reflect purely automatic facilitation in processing. This suggests an influence of strategic processing on the activation of both perceptual representations of faces and semantic representations of people.     

Characterization of necrotic meningioma using diffusion MRI,perfusion MRI,and MR spectroscopy: case report and review of the literature

Necrotic meningiomas are relatively rare, accounting for 1.3–3.9% of primary intracranial tumours and for 10–15% of meningiomas, but are of special clinical importance as they may resemble metastases or malignant gliomas. We report the magnetic resonance findings of diffusion-weighted imaging, perfusion-weighted imaging, and spectroscopy in a patient with a necrotic meningioma, in whom clinical symptoms and signs suggested a central nervous system infection.     

Absence of protein G-Fc interaction in ficin-derived mouse IgG1 digests

Typical procedure for IgG fragmentation is based on proteolytic cleavage at the hinge region and usually involves a post-digestion purification step. In mice, IgG1 has been found to bind poorly to protein A. As a result, protein G chromatography could be considered as an alternative for Fc removal. Protein G is generally expected to bind specifically to the Fc region of IgG, but applying protein G for the purification of Fab2 fragment of mouse monoclonal IgG1 under standard physiological conditions, we obtained reproducible clone-independent negligible protein G-Fc reactivity and strong protein G-Fab2 interaction.