Az arabinóz és a laktóz metabolizmus kölcsönhatásainak vizsgálata Aspergillus nidulans-ban = Interactions between the arabinose and lactose metabolism in Aspergillus nidulans

Kutatásaink azon munkák folytatása volt, melynek keretében az Aspergillus nidulans fonalas gomba béta-galaktozidáz enzim aktivitásának képződését tanulmányoztuk. Jelen pályázatban a témát kiterjesztettük és elmélyítettük. Izoláltuk és klónoztuk a gombában előforduló összes (4 db) béta-galaktozidázt kódoló gént (BgaA-D), és jellemeztük kifejeződésük szabályozását. Ezek alapján A. nidulans-ban a BGAC a fő béta-galaktozidáz enzim. Elsőként izoláltunk fonalas gombafajból laktóz permeáz gént (LacA), melyre nézve hiánymutánst hoztunk létre, és ennek segítségével karakterizáltuk kifejeződésének szabályozását. Izotópos vizsgálatok révén a laktóz permeázt biokémiai szempontból is jellemeztük. Bebizonyítottuk, hogy mind a BgaC, mind a LacA kifejeződése CreA-függő karbon katabolit represszió alatt áll. Ugyancsak bebizonyítottuk, hogy az említett szabályozási mechanizmusnak determinánsa a tenyészet specifikus növekedési rátája, és egy adott specifikus növekedési ráta érték alatt derepresszió következik be. Talán legérdekesebb felfedezésünk egy új D-galaktóz lebontási útvonal volt, mely a Leloir-útvonallal párhuzamosan működik. Az első, aldóz reduktáz enzim(ek) által katalizált lépés alapján reduktívnak elkeresztelt útvonal a D-galaktóz dulcitollá (galaktitollá) történő, NADPH-függő redukcióját, majd ennek L-szorbózzá történő, NAD+-függő, L-arabitol dehidrogenáz katalizálta dehidrogénezését foglalja magába. A glikolízisig tartó további reakciókban a fruktokináz enzim is szerepel. | This research is based on those aimed to investigate the regulation of formation of the beta-galactosidase activity in the filamentous fungus Aspergillus nidulans. In this project, this topic was extended and included a more in-depth approach. We have isolated and cloned all the four beta-galactosidase-like genes of the fungus (BgaA-D), and characterized the regulation of their expression. We concluded that in A. nidulans, BGAC is the major beta-galactosidase. We have isolated and cloned a lactose permease (LacA), which was the first of its kind from a filamentous fungus. A LacA deletion mutant was created to study the regulation of gene expression. Using labelled lactose, LACA was also characterized from the biochemical point of view. Evidence was provided that the regulation of BgaC and LacA is under CreA-dependent carbon catabolite regulation. We have shown that this regulatory mechanism is determined by the specific growth rate, and that under a certain, 'critical' growth rate carbon derepression occurs. Arguably our most interesting discovery was a new D-galactose catabolic pathway that operates in parallel to the Leloir-pathway. The pathway is called reductive after the first step that involves the NADPH-dependent reduction of D-galactose into galactitol (dulcitol). Galactitol is subsequently reduced into L-sorbose by the NAD+-dependent L-arabinitol dehydrogenase. The subsequent reactions include fructokinase, which channels the carbon into the glycolytic pathway

Stigma, pluralistic ignorance, and attitudes toward seeking mental health services among police officers

Due to the stressors inherent in the law enforcement profession, police officers may be at increased risk for a variety of personal and mental health-related concerns. Despite these tendencies, officers have historically refrained from seeking psychological services. Several factors have been identified to explain their hesitance, including public stigma and self-stigma regarding mental health issues. In this study, sworn police officers in Texas and Oklahoma completed a 62-item online survey related to their attitudes toward seeking mental health services, mental health stigma, willingness to seek services, and perceptions of other officers' willingness to seek services. The first objective of the study was to identify the role of public stigma and self-stigma in predicting attitudes toward seeking mental health services among police officers. Consistent with the study hypotheses, the results indicate that public stigma and self-stigma were negatively correlated with attitudes toward seeking professional psychological help. Furthermore, self-stigma fully mediated the relationship between public stigma and attitudes toward seeking help, and the overall model explained 56% of the variance in attitude scores. Previous research has suggested that officers may tend to underestimate their colleagues' willingness to seek psychological services, thus demonstrating the concept of pluralistic ignorance. The second objective of the study was to develop a more comprehensive understanding of the pluralistic ignorance effect as it pertains to help-seeking attitudes among police officers, with regard to several common presenting concerns. As expected, results suggest that officers underestimated their colleagues' willingness to seek mental health services for family issues, depression, posttraumatic stress disorder, substance abuse, and physiological complaints due to stress. In other words, officers tended to believe that their peers were less willing to seek mental health services than they actually were. Implications for training and future research are discussed

Intellectual Courage and the Social Construction of Terrorism: Embodying Reality.

Undertaking the exploration of the diverse, thought-provoking interpretations students provided for the words “terrorism” and “terrorist” is the basis of this work. The purpose in describing their interpretations is to acknowledge, in some instances, their acceptance of and resistance to “official” definitions and versions of “reality” regarding terrorism and terrorist. My interest is in showing how reality is constructed and experienced by students and how we as researchers and educators may create new possibilities of reality. This display of reality utilizes seven female students’ written discourse and is presented through the lens of sociological, political, and educational theories. Over the years I have taught sociology, social theory, research methods and political science. I have watched my students react with fascination (mostly positive, but sometimes negative) when learning about other cultures, belief systems, and values; expand their critical thinking skills; accept and reject elements of official doctrine and mass media produced acquiescent knowledge; and realize how the United States, with its hegemonic standing, culture, beliefs and values, affects and is affected by the rest of the world. In planning this study, I wanted to know how my students assemble their “subjective” social reality and how they perceive, interpret, and experience “objective” world realities. The title of this work, Intellectual Courage and the Social Construction of Terrorism: Embodying Reality, reflects the three main constructs: intellectual courage, social construction, and reality. The results display an expression of open-mindedness without intimidation. When discussing and analyzing their socially constructed realities, many students were able to think more creatively and critically when viewing “reality” associate with terrorists and terrorism