Beyond Single-Cell Analysis of Metallodrugs by ICP-MS: Targeting Cellular Substructures

Platinum compounds such as cisplatin (cisPt) embody the backbone of combination chemotherapy protocols against advanced lung cancer. However, their efficacy is primarily limited by inherent or acquired platinum resistance, the origin of which has not been fully elucidated yet, although of paramount interest. Using single cell inductively coupled plasma mass spectrometry (SC-ICP-MS), this study quantifies cisPt in single cancer cells and for the first time in isolated nuclei. A comparison of cisPt uptake was performed between a wild type (wt) cancer cell line and related resistant sublines. In both, resistant cells, wt cells, and their nuclei, cisPt uptake was measured at different incubation times. A lower amount of cisPt was found in resistant cell lines and their nuclei compared to wt cells. Moreover, the abundance of internalized cisPt decreased with increasing resistance. Interestingly, concentrations of cisPt found within the nuclei were higher than compared to cellular concentrations. Here, we show, that SC-ICP-MS allows precise and accurate quantification of metallodrugs in both single cells and cell organelles such as nuclei. These findings pave the way for future applications investigating the potency and efficacy of novel metallodrugs developed for cancer treatment.     

Semantic contextual cuing and visual attention.

Since M. M. Chun and Y. Jiang's (1998) original study, a large body of research based on the contextual cuing paradigm has shown that the visuocognitive system is capable of capturing certain regularities in the environment in an implicit way. The present study investigated whether regularities based on the semantic category membership of the context can be learned implicitly and whether that learning depends on attention. The contextual cuing paradigm was used with lexical displays in which the semantic category of the contextual words either did or did not predict the target location. Experiments 1 and 2 revealed that implicit contextual cuing effects can be extended to semantic category regularities. Experiments 3 and 4 indicated an implicit contextual cuing effect when the predictive context appeared in an attended color but not when the predictive context appeared in an ignored color. However, when the previously ignored context suddenly became attended, it immediately facilitated performance. In contrast, when the previously attended context suddenly became ignored, no benefit was observed. Results suggest that the expression of implicit semantic knowledge depends on attention but that latent learning can nevertheless take place outside the attentional field. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modelling the effect of ethanol on growth rate of food spoilage moulds

The effect of ethanol (E) on the radial growth rate (mu) of food spoilage moulds (Aspergillus candidus, Aspergillus flavus, Aspergillus niger, Cladosporium cladosporioides, Eurotium herbariorum, Mucor circinelloides, Mucor racemosus, Paecilomyces variotii, Penicillium chrysogenum, Penicillium digitatum, Rhizopus oryzae and Trichoderma harzianum) was assessed in Potato Dextrose Agar (PDA) medium at a(w) 0.99, 25 degrees C. In order to model this effect, the Monod type equation described previously by Houtsma et al. (Houtsma, P.C., Kusters, B.J.M., de Wit, J.C., Rombouts, F.M., Zwietering, M.H., 1994. Modelling growth rates of Listeria monocytogenes as a function of lactate concentration. Int. J. Food. Microbiol. 24, 113-123.) was re-parameterised: mu = mu(opt)[K(E(max)-E)/K E(max)-2KE+E(max)E]; E(max) (%, wt/wt): ethanol concentration at which no growth occurs, K (%, wt/wt): ethanol concentration at which mu = mu(opt)/2, mu(opt) (mm day(-1)): growth rate at 0% ethanol. The model was capable of describing curves, mu vs. E, with either a concave shape (KE(max)/2) with a good accuracy (root mean square error (RMSE) < or = 0.136) with the notable exception of R. oryzae and T. harzianum. After growth rate data were square-root transformed to stabilise the variance, E(max) was estimated in the range 3% to 5% for all moulds with the exception of T. harzianum (E(max) 2.14%) and P. variotii (E(max) 6.43%). Ethanol would appear an effective additional barrier to inhibit fungal growth in food products and would represent an interesting alternative to the use of preservatives.     

Wavelet de-noising of laser Doppler reactive hyperemia signals to diagnose peripheral arterial occlusive diseases

In order to improve peripheral arterial occlusive diseases (PAOD) diagnoses, five de-noising algorithms based on a multiresolution analysis computed with wavelets are applied on reactive hyperemia signals obtained with the laser Doppler flowmetry technique. Results are presented on recordings acquired on patients suffering from PAOD and on healthy subjects.     

A contextual analysis of externalizing and mixed syndrome boys: When syndromal similarity obscures functional dissimilarity.

A contextualized approach to psychopathology that focuses on children's responses to events rather than overall behavior output was examined. Teachers rated boys in special education classrooms using a standardized syndromal instrument and one that assessed boys' social environments and their responses to them. Externalizing and mixed (aggressive and withdrawn) syndrome groups showed distinctive response patterns that could not be derived from syndrome scores, with externalizers showing aggression in response to aversive events, and mixed boys showing contextually anomalous responses to positive events. The externalizing and mixed groups each consisted of functionally distinct subgroups that were not detected using syndrome measures. The results clarify how syndromal measures can confuse psychologically distinct children and demonstrate the utility of a teacher-report method that is efficient to administer and sensitive to contextual influences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reasons for drinking, alcohol use, and alcoholism among Mexican Americans and non-Hispanic Whites.

Estimated associations of subjective reasons for drinking with heavy drinking (HD), frequent drinking (FD), and alcohol abuse or dependence (AAOD). Respondents were 725 Mexican-American and 915 non-Hispanic White community residents who reported drinking at least once in the 6 mo before being interviewed. Each reason for drinking and number of reasons given for drinking were associated with HD, FD, or AAOD. However, multivariate models suggested that different reasons may be associated with different types of alcohol involvement. Cultural differences in alcohol involvement were typically not accounted for by cultural differences in reasons for drinking. Drinking to cheer up or to loosen up around people and drinking to induce sleep had different associations with HD and AAOD in different cultural groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Theoretical characteristics of a tunable two-electrode Fabry-Perot(TEFP) laser diode

The theoretical tuning characteristics of a two-electrode Fabry-Perot (TEFP) laser diode are derived using a relative simple model. This type of laser can be used as a tunable source. Tuning can be achieved by driving the device along a constant-power contour while the wavelength changes during the travel of the operating point. The characteristics indicate constant-power FM and constant-wavelength AM operating modes for the TEFP device. The laser exhibits ability similar to that of a multielectrode distributed-feedback or distributed-Bragg-reflector laser     

Correlation between modes of drinking and modes of driving as reported by students at two American universities

This paper examines the correlates and predictors of driving under the influence behaviors (DUIBs) during the past month by college students. Measures of heavy episodic drinking, monthly drinking frequency, monthly drinking variance, monthly drinks per occasion and reported marijuana use are compared as predictors net of other predictive factors. A cross-sectional telephone survey was conducted with college students by a university social science research laboratory. Respondents attended two large public universities located in the southwestern part of the US. Participants included 803 randomly selected college students. The interview schedule included items from the Core Alcohol and Drug Survey and the College Alcohol Risk Assessment Guide. Several additional last-drinking-event items were also developed for the interview. Bivariate analyses indicate that marijuana use (past year), heavy episodic drinking, reports of DUIBs (driving under the influence or riding with a driver who is under the influence) in the past year, monthly frequency of drinking, the average number of drinks consumed when drinking and age are correlates of DUIBs during the past month. Multivariate analyses indicate past year DUIBs, monthly frequency of drinking and monthly marijuana use predicted recent DUIB.