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Oxytocin is a hormone that may not only influence reproductive mechanisms in mammals but also their social behavior, including pair bonding. We therefore tested if the concentrations of oxytocin and other hormones reveal mate preferences of 13 mares in estrus. Each mare was first exposed to two stallions (haphazardly selected out of seven) and her behavior recorded. The mare was then returned to her box (i.e., no contact to stallions during that time). Approximately 4.5 hours later, venous blood samples were collected every minute during 30 minutes preceding exposure to one of the two previously used stallions, 6 minutes during exposure, and 30 minutes after exposure back in the mare's box. The procedure was repeated in the consecutive estrus cycle, with the difference that the mare was each exposed to the other of the two stallions during oxytocin measurements. In 20 of the 26 trials, oxytocin concentrations were significantly elevated during exposure to the stallion, without significant associations to cortisol and estradiol concentrations. We found no significant association between oxytocin secretion and preferences in the previous choice situation. While estradiol concentration showed a high repeatability over the two cycles, we found considerable intraindividual differences in oxytocin and cortisol plasma concentration among the two cycles. Partially, the variation in oxytocin concentrations could be linked to the time of ovulation, with lower oxytocin plasma concentrations in mares which ovulated later than expected. In conclusion, when teasing under experimental conditions, we found high interindividual and intraindividual variation among mares in the increase of oxytocin plasma concentrations, depending on the timing of ovulation. However, oxytocin levels seemed to be no predictor of mare preference.

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The hspArpoH1 and hspBCdegP heat shock operons of Bradyrhizobium japonicum are preceded by a novel, conserved DNA element of approximately 100 bp, which is responsible for the temperature-regulated transcription of their sigma70-type promoters. We designated this motif ROSE for repression of heat shock gene expression and found additional ROSE elements upstream of two newly identified heat shock operons. A critical core region in the hspA-associated ROSE1 was defined by introducing insertions or deletions. While four mutants retained the ability to repress transcription of the hspArpoH1 operon, five deletion mutants produced elevated hspA mRNA levels under low-temperature growth conditions. Derepression was confirmed by increased RpoH1 levels in non-heat-shocked cells from one of these mutants and by strains that contained a translational hspA-lacZ fusion associated with mutated ROSE1 elements. The hspArpoH1 operon was efficiently transcribed in vitro, and a deletion of ROSE1 did not impair this activity. Gel retardation experiments demonstrated that a protein in non-heat-shocked cells specifically binds to the intact ROSE1 element but not to a mutated element lacking the core region. Taken together, these results indicate that a central region of ROSE serves as a binding site for a repressor protein under standard growth conditions in order to prevent the undesired transcription of heat shock genes.

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Information on treatment and rehabilitation approaches for persons with serious mental illness was examined in 28 introductory and 14 abnormal psychology textbooks. Both drug and hospital treatment received significantly more coverage than did community rehabilitation approaches in both types of texts. In introductory texts, community rehabilitation received no more coverage than lobotomy. Texts were also examined for their mention of 12 community rehabilitation approaches in current practice. Both types of texts gave a dated presentation of mental health services. However, description of community approaches in abnormal textbooks was more detailed and research-based than in introductory texts. It was hypothesized that textbook coverage mirrors the lack of psychiatric rehabilitation research reported in psychological journals.

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Evaluated a large-city adaptation of the assertive community treatment (ACT) model (Stein & Test, 1980). Outcomes were examined after 1 year for 82 clients, averaging over 17 lifetime psychiatric hospitalizations, randomly assigned either to ACT or to a drop-in (DI) center. After 1 year, 76% of the ACT clients and only 7% of DI clients were involved in the respective programs. The ACT team averaged 2 home and community visits per week to each client. ACT clients averaged significantly fewer state hospital admissions and state hospital days than did DI clients. ACT clients reported greater satisfaction with program services, fewer contacts with the police, and less difficulty with practical problems associated with psychiatric readmission. More ACT clients were known to have stable community housing. Annual per-client treatment costs for ACT were estimated to be $1,500 less than for DI.

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Much progress has been made in identifying behavioural factors that play an important role in the aetiology of diarrhoea. This short report represents results from a 1-year prospective community-based study of the aetiology of diarrhoea. It was designed to investigate, among other things, mothers' perceptions of the importance of babies' faeces and other factors in the aetiology of diarrhoea. Children whose mothers did not perceive babies' faeces to be important in causing diarrhoea had a 7.4 times greater risk of getting diarrhoea than those whose mothers recognized the relationship. The risk for contaminated food was 6.8 times greater for those children whose mothers did not recognize its importance. For the rest of the factors, there was no meaningful association. Health education should emphasize the polluting nature of babies' faeces and the need for hand-washing when there has been any contact.

PIP: A 1-year prospective study on the etiology of infantile diarrhea, conducted in an urban settlement in Papua New Guinea, revealed a strong association between mothers' perceptions that feces are polluting and the number of diarrheal episodes. Children whose mothers did not recognize feces as a source of diarrhea were 7.4 times more likely to get diarrhea than those whose mothers were aware of this association. Similarly, those whose mothers did not link contaminated food to diarrhea were 6.8 times more likely to suffer from diarrhea than their counterparts who were knowledgeable about this relationship. There was no significant correlation between the number of diarrhea episodes and the other items--maternal perceptions of the etiologic significance of dirty clothes, food dropped on the ground, cow's milk, and breast milk in diarrhea--about which mothers were questioned. Even when the data were adjusted for the potentially confounding effects of maternal age, education, employment, and socioeconomic status, the associations between feces, contaminated food, and diarrheal incidence remained significant. The highest relative risk (11 times greater) of diarrhea was found among infants of mothers who failed to recognize the etiologic significance of both infants' feces and contaminated food. These findings suggest a need to educate mothers about the importance of handwashing after every contact with their child's feces. Education is also needed on the dangers of eating food that has been dropped on the ground. Of the 479 infants studied, 296 had no episodes of diarrhea during the 1-year study period, 144 had 1 episode, 21 had 2 episodes, 10 had 3 episodes, and 8 had 4 or more episodes.

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