Structural analysis of three His32 mutants of DsbA: Support for an electrostatic role of His32 in DsbA stability

DsbA, a 21-kDa protein from Escherichia coli, is a potent oxidizing disulfide catalyst required for disulfide bond formation in secreted proteins. The active site of DsbA is similar to that of mammalian protein disulfide isomerases, and includes a reversible disulfide bond formed from cysteines separated by two residues (Cys3O-Pro31-His32-Cys33). Unlike most protein disulfides, the active-site disulfide of DsbA is highly reactive and the oxidized form of DsbA is much less stable than the reduced form at physiological pH. His32, one of the two residues between the active-site cysteines, is critical to the oxidizing power of DsbA and to the relative instability of the protein in the oxidized form. Mutation of this single residue to tyrosine, serine, or leucine results in a significant increase in stability (of similar to 5-7 kcal/mol) of the oxidized His32 variants relative to the oxidized wild-type protein. Despite the dramatic changes in stability, the structures of all three oxidized DsbA His32 Variants are very similar to the wild-type oxidized structure, including conservation of solvent atoms near the active-site residue, Cys3O. These results show that the His32 residue does not exert a conformational effect on the structure of DsbA. The destabilizing effect of His32 on oxidized DsbA is therefore most likely electrostatic in nature.

Self-Directed Behavioral Family Intervention for Parents of Oppositional Children in Rural and Remote Areas

Twenty-four parents of oppositional preschoolers were randomly assigned to either a self-directed behavioral family intervention condition (SD) or to a waitlist control group (WL). The self-directed parent training program based on self-regulation principles, consisted of a written information package and weekly telephone consultations for 10 weeks. At posttest, in comparison to the WL group, children in the SD group had lower levels of behavior problems on parent report measures of child behavior. At posttreatment, parents in the SD condition reported increased levels of parenting competence and lower levels of dysfunctional parenting practices as compared to parents in the WL condition. In addition, mothers reported lower levels of anxiety, depression, and stress as compared to mothers in the WL condition at posttreatment. Using mother's reports, gains in child behavior and parenting practices achieved at posttreatment were maintained at 4-month follow-up.

Postural control of the trunk in response to lateral support surface translations during trunk movement and loading

The postural response to translation of the support surface may be influenced by the performance of an ongoing voluntary task. This study was designed to test this proposal by applying lateral perturbations while subjects handled a load in the frontal plane. Measurements were made of medio-lateral displacement of the centre of pressure, angular displacement of the trunk and thigh in the frontal plane and intra-abdominal pressure. Subjects were translated randomly to the left and right in a variety of conditions that involved standing either quietly or with a 5 kg load in their left hand, which they were required either to hold statically or to lift or lower. The results indicate that when the perturbation occurred towards the loaded left side the subjects were able to return their centre of pressure, trunk and thigh rapidly and accurately to the initial position. However, when the perturbation occurred towards the right (away from the load) this correction was delayed and associated with multiple changes in direction of movement, suggesting decreased efficiency of the postural response. This reduced efficiency can be explained by a conflict between the motor commands for the ongoing voluntary task and the postural response, and/or by the mechanical effect of the asymmetrical addition of load to the trunk.

The impact of nutrition support on body composition in cancer outpatients receiving radiotherapy

This study investigated the change in body composition in 36 cancer outpatients receiving radiotherapy to the head and neck area (mean age: 63 ± 15 years) randomised to receive either nutrition intervention (NI; n=15) or usual care (UC; n=21). Body weight and composition were measured at the commencement of radiotherapy and 3 months later. The UC group lost significantly more weight; mean decrease = 4.3 kg, than the NI group: mean decrease = 1.1 kg (t(30)=-2.5, p=0.019). Fat-free mass loss was significantly higher in the UC group with a mean loss of 2.2 kg versus 0.3 kg in the NI group (t(30)=- 2.3, p=0.029). Body composition as measured by foot-to-foot bioelectrical impedance analysis provides more information than weight alone and can allow for tailoring of NI.

Sticks and stones will break my bones -- and words will harm too: Australia's provision of education for asylum seeker children in detention

No abstract

Who supports? The providers of social support to dual-parent families caring for young children

Previous research points to the importance of both kin and non-kin ties within social networks as sources of social support. This study examines the kin and non-kin providers of specific types of support to dual-parent low-income Australian families caring for young children. The study highlights the importance of family and friends as support providers. Study Participants tended to rely on family, including parents, siblings and other family members, and friends for emotional and information support. Parents also tended to provide material and practical support. While neighbors and community agencies offered some emotional and information support, overall, these sources were minimal. (C) 2002 Wiley Periodicals, Inc.

The effectiveness of parent management training to increase self-efficacy in parents of children with Asperger syndrome

This study was a trial of an intervention programme aimed to improve parental self-efficacy in the management of problem behaviours associated with Asperger syndrome. The intervention was compared across two formats, a I day workshop and six individual sessions, and also with a non-intervention control group. The results indicated that, compared with the control group, parents in both intervention groups reported fewer problem behaviours and increased self-efficacy following the interventions, at both 4 weeks and 3 months follow-up. The results also showed a difference in self-efficacy between mothers and fathers, with mothers reporting a significantly greater increase in self-efficacy following intervention than fathers. There was no significant difference between the workshop format and the individual sessions.

A review of peer support in the context of cancer

Peer support interventions for people with cancer, their families, and friends have been widely used throughout the world. The present study reviewed the research literature on psychosocial oncology over the past decade to assess the prevalence and contribution of articles on peer support. Using CD-Rom databases, 25 articles were retrieved for review. In each article, patients or their family members were the target group for supportive interventions, which were primarily for the delivery of peer support and included either a qualitative or quantitative evaluation of the program. A definitional taxonomy for peer support interventions, which identified eight discrete settings, was derived from three key dimensions: style of supervision, interpersonal context, and mode of delivery. The studies suggested that peer support programs help by providing emotional and informational support from the perspective of shared personal experience. However, a paucity of research-particularly randomized controlled trials-was noted. The reasons may include inherent difficulties in isolating for study what is essentially a naturalistically occurring interpersonal dynamic from the complex social and community contexts from which it emanates. The authors discuss the gap between practice and theory in this area and recommend a broader and more inclusive view of supportive care for people with cancer. (C) 2003 by The Haworth Press, Inc. All rights reserved.