The Fungal bZIP Transcription Factor AtfB Controls Virulence-Associated Processes in Aspergillus parasiticus

Fungal basic leucine zipper (bZIP) transcription factors mediate responses to oxidative stress. The ability to regulate stress response pathways in Aspergillus spp. was postulated to be an important virulence-associated cellular process, because it helps establish infection in humans, plants, and animals. Previous studies have demonstrated that the fungal transcription factor AtfB encodes a protein that is associated with resistance to oxidative stress in asexual conidiospores, and AtfB binds to the promoters of several stress response genes. Here, we conducted a gene silencing of AtfB in Aspergillus parasiticus, a well-characterized fungal pathogen of plants, animals, and humans that produces the secondary metabolite and carcinogen aflatoxin, in order to determine the mechanisms by which AtfB contributes to virulence. We show that AtfB silencing results in a decrease in aflatoxin enzyme levels, the down-regulation of aflatoxin accumulation, and impaired conidiospore development in AtfB-silenced strains. This observation is supported by a decrease of AtfB protein levels, and the down-regulation of many genes in the aflatoxin cluster, as well as genes involved in secondary metabolism and conidiospore development. Global expression analysis (RNA Seq) demonstrated that AtfB functionally links oxidative stress response pathways to a broader and novel subset of target genes involved in cellular defense, as well as in actin and cytoskeleton arrangement/transport. Thus, AtfB regulates the genes involved in development, stress response, and secondary metabolism in A. parasiticus. We propose that the bZIP regulatory circuit controlled by AtfB provides a large number of excellent cellular targets to reduce fungal virulence. More importantly, understanding key players that are crucial to initiate the cellular response to oxidative stress will enable better control over its detrimental impacts on humans.

Effects of Zinc Chelators on Aflatoxin Production in Aspergillus parasiticus

Zinc concentrations strongly influence aflatoxin accumulation in laboratory media and in food and feed crops. The presence of zinc stimulates aflatoxin production, and the absence of zinc impedes toxin production. Initial studies that suggested a link between zinc and aflatoxin biosynthesis were presented in the 1970s. In the present study, we utilized two zinc chelators, N,N,N′,N′-tetrakis (2-pyridylmethyl) ethane-1,2-diamine (TPEN) and 2,3-dimercapto-1-propanesulfonic acid (DMPS) to explore the effect of zinc limitation on aflatoxin synthesis in Aspergillus parasiticus. TPEN but not DMPS decreased aflatoxin biosynthesis up to six-fold depending on whether A. parasiticus was grown on rich or minimal medium. Although we observed significant inhibition of aflatoxin production by TPEN, no detectable changes were observed in expression levels of the aflatoxin pathway gene ver-1 and the zinc binuclear cluster transcription factor, AflR. Treatment of growing A. parasiticus solid culture with a fluorescent zinc probe demonstrated an increase in intracellular zinc levels assessed by increases in fluorescent intensity of cultures treated with TPEN compared to controls. These data suggest that TPEN binds to cytoplasmic zinc therefore limiting fungal access to zinc. To investigate the efficacy of TPEN on food and feed crops, we found that TPEN effectively decreases aflatoxin accumulation on peanut medium but not in a sunflower seeds-derived medium. From an application perspective, these data provide the basis for biological differences that exist in the efficacy of different zinc chelators in various food and feed crops frequently contaminated by aflatoxin.

Sexual preference for child and aggressive stimuli: comparison of rapists and child molesters using auditory and visual stimuli

154 Ss were tested using penile plethysmography as part of intake into a voluntary inpatient sex offender treatment program. The testing protocol included slide stimuli of nude males and females in four age categories ranging from age 1 to adult; audiotaped descriptions of sexual activity with children of both genders which included fondling, sexual contact with no resistance, coercive sexual contact, sexual assault, nonsexual assault, and consensual sexual contact with an adult; videotaped depictions of rape of an adult woman, nonsexual assault of an adult woman and consensual sexual involvement with an adult woman, and audiotaped descriptions that paralleled the videotapes. The results indicated that child molesters (male victim) show a decidedly more offense related arousal profile than either child molesters (female victim) or rapists, and that the profiles of child molesters (female victim) and rapists are remarkably similar, although statistically significantly different from each other. Rapists respond significantly more to rape and nonsexual assault than either of the two child molester groups, with child molesters with female victims responding more than those with male victims. In all three groups, the highest level of noncoercive adult responding was to women, with differences among offense groups present for visual stimuli, but not in response to auditory stimuli. Overall, the patterns of results are similar whether they are based on composites across stimulus modality or on the individual stimuli.

The relationship between treatment goals and recidivism among child molesters

Preliminary findings from a longitudinal outcome study of sex offender treatment are presented. Ss included 76 child molesters who were treated in a comprehensive relapse prevention program, and 79 molesters who were randomly assigned to a control (no treatment) condition. Three sets of findings are reported: survival analyses of time to reoffense; in-treatment change data relevant to the program's treatment goals; and the relationships between treatment measures and risk of reoffense. Over an average followup period of 38 months, there was a trend for treatment Ss to be at lower risk for both sex and violent crimes than were controls. Treatment Ss showed significant progress towards treatment goals of increased acceptance of personal responsibility for their crimes and decreased levels of deviant sexual arousal. Measures of personal responsibility, however, were not related to risk of rearrest for new sex crimes. Treatment Ss with high levels of both deviant and nondeviant sexual arousal were more likely to commit new sex offenses, but not other violent offenses. The strongest predictor in the study was a measure of the Ss' skills in applying the relapse prevention model, with highly skilled Ss being less likely to commit new sex crimes.

Age-related changes in stress experienced by families with a child who has developmental delays

The hypothesis that stress in families increases as a child with developmental delays grows older was evaluated. Mothers with children ranging in age from 2 to 18 years were assigned to a preschool, middle childhood, or adolescent group and asked to complete the Parenting Stress Index (PSI). Results indicated that Child Domain scores were high for all groups, but Parent Domain scores were within normal limits. The middle childhood group was consistently higher in both domains than either the younger or older groups. Degree of handicap was not associated with mothers' stress in the preschool group, but was related to PSI scores for both other groups. Behavior problems were highly correlated with maternal stress for the middle childhood and adolescent groups (data not available for preschool group).

Distance education and the citizens of Wisconsin -- narrowing the gap

This article presents a program model for reaching parents of adolescents with hospital-based content and expertise.

Improving community education strategies for mental health promotion

Mental health promotion may be conceptualized as a process of communication comprising five basic elements: message content, message medium, target audience, goals, and providers of educational services (sender). This paper, based on a review of the mental health education literature, examines each element in terms of strategies and issues which should be considered in the development of effective mental health promotion campaigns. The s synergistic relationship among these elements and the need for evaluation are also discussed.

Portrayal of mental illness in Canadian newspapers

The present article reports results from a content analysis of 103 newspaper reports taken from eight major Canadian newspapers, and selected at random from the Canadian Newspaper Index. The portrayal of mental illness and mentally ill persons in these reports was compared with that in samples of articles taken from two comparison mental health publications not receiving popular circulation. As compared with these latter publications, the content analysis indicated that the newspapers portrayed mental illness and the mentally ill in a manner which could be described as essentially pejorative, thus seeming to support frequent observations and complaints from the mental health establishment about inadequate or unfair coverage of mental illness in the popular print media. At the same time, the newspaper medium appeared to present more favourable images of nontraditional (example: community-based) mental health practices, than of traditional (example: hospital-based) practices. Implications of such results for the attitudes and beliefs of the general public vis-à-vis mental illness are offered, with special reference to the influence of the print media.