Effector ExoU from the type III secretion system is an important modulator of gene expression in lung epithelial cells in response to Pseudomonas aeruginosa infection

Pseudomonas aeruginosa is an important pathogen in immunocompromised patients and secretes a diverse set of virulence factors that aid colonization and influence host cell defenses. An important early step in the establishment of infection is the production of type III-secreted effectors translocated into host cells by the bacteria. We used cDNA microarrays to compare the transcriptomic response of lung epithelial cells to P. aeruginosa mutants defective in type IV pili, the type III secretion apparatus, or in the production of specific type III-secreted effectors. Of the 18,000 cDNA clones analyzed, 55 were induced or repressed after 4 It of infection and could be classified into four different expression patterns. These include (i) host genes that are induced or repressed in a type III secretion-independent manner (32 clones), (ii) host genes induced specifically by ExoU (20 clones), and (iii) host genes induced in an ExoU-independent but type III secretion dependent manner (3 clones). In particular, ExoU was essential for the expression of immediate-early response genes, including the transcription factor c-Fos. ExoU-dependent gene expression was mediated in part by early and transient activation of the AN transcription factor complex. In conclusion, the present study provides a detailed insight into the response of epithelial cells to infection and indicates the significant role played by the type III virulence mechanism in the initial host response.

Differential involvement of rat medial prefrontal cortex dopamine receptors in modulation of hypothalamic-pituitary-adrenal axis responses to different stressors

Recent investigations have implicated the medial prefrontal cortex (mPFC) in modulation of subcortical pathways that contribute to the generation of behavioural, autonomic and endocrine responses to stress. However, little is known of the mechanisms involved. One of the key neurotransmitters involved in mPFC function is dopamine, and we therefore aimed, in this investigation, to examine the role of mPFC dopamine in response to stress in Wistar rats. In this regard, we infused dopamine antagonists SCH23390 or sulpiride into the mPFC via retrodialysis. We then examined changes in numbers of cells expressing the c-fos immediate-early gene protein product, Fos, in subcortical neuronal populations associated with regulation of hypothalamic-pituitary-adrenal (HPA) axis stress responses in response to either of two stressors; systemic injection of interleukin-1beta, or air puff. The D-1 antagonist, SCH23390, and the D-2 antagonist, sulpiride, both attenuated expression of Fos in the medial parvocellular hypothalamic paraventricular nucleus (mpPVN) corticotropin-releasing factor cells at the apex of the HPA axis, as well as in most extra-hypothalamic brain regions examined in response to interleukin-1beta. By contrast, SCH23390 failed to affect Fos expression in response to air puff in any brain region examined, while sulpiride resulted in an attenuation of the air puff-induced response in only the mpPVN and the bed nucleus of the stria terminalis. These results indicate that the mPFC differentially processes the response to different stressors and that the two types of dopamine receptor may have different roles.

The outcome in Australian children with hyperinsulinism of infancy: early extensive surgery in severe cases lowers risk of diabetes

AIMS Hyperinsulinism of infancy (HI) is characterized by unregulated insulin secretion in the presence of hypoglycaemia, often resulting in brain damage. Pancreatic resection for control of hypoglycaemia is frequently resisted because of the risk of diabetes mellitus (DM). We investigated retrospectively 62 children with HI from nine Australian treatment centres born between 1972 and 1998, comparing endocrine and neurological outcome in 28 patients receiving medical therapy alone with 34 who required pancreatic resection to control their hypoglycaemia. METHODS History, treatment and clinical course were ascertained from file audit and interview. Risk of DM (hazard ratio) attributable to age at surgery (< vs. greater than or equal to 100 days at last pancreatectomy) and extent of resection (< vs. greater than or equal to 95%) were calculated using Cox proportional hazards regression and categorical variables compared by the chi(2) -test. Neurological outcome (normal, mild deficit or severe deficit) was derived from the most authoritative source. RESULTS Surgically treated patients had a greater birthweight, earlier presentation and higher plasma insulin levels. Of 18 infants < 100 days and 16 greater than or equal to 100 days of age at surgery, four (all greater than or equal to 100 days) became diabetic as an immediate consequence of surgery and five (two < 100 days and three greater than or equal to 100 days) became diabetic 7-18 years later. Surgery greater than or equal to 100 days and pancreatectomy greater than or equal to 95% were associated with development of diabetes (HR = 12.61, CI 1.53-104.07 and HR = 7.03, CI 1.43-34.58, respectively). Neurodevelopmental outcome was no different between the surgical and medical groups with 44% overall with neurological deficits. Patients euglycaemic within 35 days of the first symptom of hypoglycaemia (Group A) had a better neurodevelopmental outcome than those still hypoglycaemic > 35 days from first presentation (Group B) (P = 0.007). Prolonged hypoglycaemia in Group B was due either to delayed diagnosis or to need for repeat surgery because of continued hypoglycaemia. Within Group A, medically treated patients (who presented later with apparently milder disease) had a higher incidence of neurodevelopmental deficit (n = 15, four mild, three severe deficit) compared with surgically treated patients (n = 18, two mild, none severe deficit) (P < 0.025). CONCLUSIONS Poor neurodevelopmental outcome remains a major problem in hyperinsulinism of infancy. Risk of diabetes mellitus with pancreatectomy varies according to age at surgery and extent of resection. Patients presenting early with severe disease have a better neurodevelopmental outcome and lower risk of diabetes if they are treated with early extensive surgery.

Randomized controlled trial of an educational intervention for managing fatigue in women receiving adjuvant chemotherapy for early-stage breast cancer

Purpose To evaluate the efficacy of a psychoeducational intervention in improving cancer-related fatigue. Patients and Methods This randomized controlled trial involved 109 women commencing adjuvant chemotherapy for stage I or II breast cancer in five chemotherapy treatment centers. Intervention group patients received an individualized fatigue education and support program delivered in the clinic and by phone over three 10- to 20-minute sessions 1 week apart. Instruments included a numeric rating scale assessing confidence with managing fatigue; 11-point numeric rating scales measuring fatigue at worst, average, and best; the Functional Assessment of Cancer Therapy-Fatigue and Piper Fatigue Scales; the Cancer Self-Efficacy Scale; the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30; and the Hospital Anxiety and Depression Scale. For each outcome, separate analyses of covariance of change scores between baseline (T1) and the three follow-up time points (T2, T3, and T4) were conducted, controlling for the variable's corresponding baseline value. Results Compared with the intervention group, mean difference scores between the baseline (T1) and immediate after the test (T2) assessments increased significantly more for the control group for worst and average fatigue, Functional Assessment of Cancer Therapy-Fatigue, and Piper fatigue severity and interference measures. These differences were not observed between baseline and T3 and T4 assessments. No significant differences were identified for any pre- or post-test change scores for confidence with managing fatigue, cancer self-efficacy, anxiety, depression, or quality of life. Conclusion Preparatory education and support has the potential to assist women to cope with cancer-related fatigue in the short term. However, further research is needed to identify ways to improve the potency and sustainability of psychoeducational interventions for managing cancer-related fatigue.

The development of self-awareness and relationship to emotional functioning during early community reintegration after traumatic brain injury

Impaired self-awareness may affect clients' emotional status, engagement in rehabilitation and community reintegration following traumatic brain injury (TBI). The study aimed to investigate the relationship between self-awareness, emotional distress and community integration in adults with TBI during the transition from hospital to the community. Thirty-four rehabilitation clients with TBI were assessed in the week before and 2 months after discharge home. Measures of self-awareness and emotional functioning were administered predischarge and repeated at follow-up along with a measure of community integration. Nonparametric tests were used to compare levels of self-awareness and emotional distress pre- and postdischarge, their interrelationships and association with community integration. Self-awareness significantly increased following discharge, and a trend towards increased depression was found. There were no consistent relationships found between level of self-awareness, emotional functioning, and community integration. The development of self-awareness in the immediate postdischarge phase suggests this is an important time for clinical interventions targeting compensation strategies and adjustment to disability.