Coding With R-PAS: Does Prior Training With the Exner Comprehensive System Impact Interrater Reliability Compared to Those Examiners With Only R-PAS-Based Training?

The Rorschach Inkblot Method (RIM) is a performance-based personality assessment instrument used in both clinical and research settings worldwide. This investigation examines response-level, interrater reliability of U.S. graduate students enrolled in the same doctoral program and divided into two unique participant groups: 20 of those with previous Comprehensive System (CS) training background who are now trained in Rorschach Performance Assessment System (R-PAS; initial coders N = 11, blind coders N = 9), and 19 of those trained solely with R-PAS (initial coders N = 10, blind coders N = 9). Trainees' coding was analyzed based on a sample of 50 protocols (half per group) representing a total of 1,189 responses. Blind coding was used among trainees and coding between the two investigated training groups was analyzed for each variable at the response level and expressed as percent agreement, Gwet's AC, and kappa values. Rates of agreement between the trainees were similar across both groups, and most of the concordance rates can be characterized as excellent. Overall, these results suggest that trainees may learn how to code R-PAS variables with similar reliability levels whether or not they had prior CS knowledge.

Chemical and mutagenic patterns of airborne particulate matter collected in 17 Italian towns

The mutagenicity of airborne particulate matter collected in 17 towns of Italy in 1990 was assessed using the Ames test. The mutagenicity of crude extract correlated with amount of lead, suggesting the direct contribution of gasoline car exhausts. Moreover, the mutagenicity correlated with particulate matter amounts. An inverse correlation with temperature was observed. The crude extracts were fractionated in acid, basic, and neutral fractions. The latter was further separated into polycyclic aromatic hydrocarbon (PAH), polar, and nonpolar fractions. Acid and polar fractions showed the higher mutagenicity. Average recovery of mutagenicity was about 60%.

Putrescine Channels in the Plasma Membrane of Arabidopsis thaliana

The patch-clamp technique was used in the whole-cell configuration to study plasma membrane channels permeable to the diamine putrescine in protoplasts isolated from cultured cells of Arabidopsis thaliana L. Under our experimental conditions, no channels selectively mediating putrescine influx were observed. Inward K+ channels showed a low permeability to putrescine, the permeability ratio of putrescine relative to K+ being around 0.1. Further characterization of the previously identified outward channels mediating putrescine efflux (R. Colombo, R. Cerana, N. Bagni [1992] Biochem Biophys Res Commun 182: 1187-1192) indicated that their activity was regulated by the overall ion concentration of the external medium.

Tonoplast K+ channels in Arabidopsis thaliana are activated by cytoplasmic ATP

The effect of ATP on the slow vacuolar cation channels in the tonoplast of suspension-cultured cells of Arabidopsis thaliana L. was examined using the patch clamp technique in the whole-vacuole configuration. The channels were specifically activated by cytoplasmic ATP, other nucleotides (ADP, GTP and nonhydrolizable ATP analogues) being ineffective.

Correlations between 15 polycyclic aromatic hydrocarbons (PAH) and the mutagenicity of the total PAH fraction in ambient air particles in La Spezia (Italy)

Airborne particulate matter has been monitored 4 times a month for 1 year (1988) in the city of La Spezia (Italy). The polycyclic aromatic hydrocarbon (PAH) fractions were extracted, purified and characterized for the content of 15 individual PAH. In general when concentrations of individual PAH were compared statistical correlation was obtained. Mutagenicity studies were performed by the use of the Ames plate test with the Salmonella strains TA98, TA100, TA98NR and TA98DNP6 with and without metabolic activation (S9 mix). The TA98 strain was by far the most responsive and the S9 mix was absolutely required as expected when PAH are assayed. Besides mutagenicity, toxicity was also considered and it proved to be correlated with mutagenicity in TA98, +S9. The TA98NR and TA98DNP6 strains showed no appreciable differences from the parental strain TA98 indicating the absence of significant amounts of direct-acting nitro derivatives in our PAH samples. Of the 15 PAH considered in this study the amounts of cyclopental[c,d]pyrene (CPP) correlated best with mutagenicity. The role of CPP in contributing to the indirect mutagenicity of urban air PAH samples is discussed.

Genotoxicity of vanadium compounds in yeast and cultured mammalian cells

The ability of vanadium compounds to induce genetic activity was investigated in D7 and D61M strains of Saccharomyces cerevisiae and in Chinese hamster V79 cell line. In our previous work, ammonium metavanadate (pentavalent form, V5) induced mitotic gene conversion and point reverse mutation in the D7 strain of yeast. The genotoxicity was reduced by the presence of S9 fraction, which probably reduced pentavalent vanadium to the tetravalent form. In the present study, vanadyl sulfate (tetravalent form, V4) induced no convertants and revertants in yeast cells harvested from stationary growth phase. With yeast cells from logarithmic growth phase, which contain high levels of cytochrome P-450, a significant increase in genetic effects was observed. Further experiments, performed by treating cells harvested from logarithmic growth phase in the presence of cytochrome P-450 inhibitors, indicated that the monooxygenase system influenced the genotoxicity of metavanadate while the genetic activity of vanadyl remained unaffected. Aneuploidy effect in the D61M strain of Saccharomyces cerevisiae was induced by either V5 or V4, confirming that vanadium compounds are potentially antitubulin agents in eukaryotic cells. Although these compounds are very toxic in V79 cells, no mutagenic effect was observed in the presence or in the absence of S9 fraction.

Vanadium: genetical and biochemical investigations

Ammonium metavanadate was studied for its ability to induce mitotic gene conversion and reverse point mutation in the D7 strain of Saccharomyces cerevisiae. Metavanadate increased the convertant and revertant frequencies; the highest activity was observed without metabolic activation. This indicated that the S9 hepatic fraction and yeast cells in logarithmic phase (and containing a high level of cytochrome P450) biotransform vanadate, probably reducing it to vanadyl. In addition, the effect of ammonium metavanadate on the hepatic monooxygenase system was studied in mice by measuring the level of cytochrome P450 and determining the activities of aminopyrine N-demethylase, p-nitroanisole O-demethylase and 7-ethoxycoumarin O-deethylase in mouse liver microsomal fraction. The results indicated that this compound reduced mono-oxygenase activity and also the level of cytochrome P450.