Understanding Spin-Triplet Excited States in Carbene-Metal-Amides.

Carbene-metal-amides (CMAs) are emerging delayed fluorescence materials for organic light-emitting diode (OLED) applications. CMAs possess fast, efficient emission owing to rapid forward and reverse intersystem crossing (ISC) rates. The resulting dynamic equilibrium between singlet and triplet spin manifolds distinguishes CMAs from most purely organic thermally activated delayed fluorescence emitters. However, direct experimental triplet characterization in CMAs is underutilized, limiting our detailed understanding of the ISC mechanism. In this work, we combine time-resolved spectroscopy with tuning of state energies through environmental polarity and metal substitution, focusing on the interplay between charge-transfer (3CT) and local exciton (3LE) triplets. Unlike previous photophysical work, we investigate evaporated host : guest films of CMAs and small-molecule hosts for increased device relevance. Transient absorption reveals an evolution in the triplet excited-state absorption (ESA) consistent with a change in orbital character between hosts with differing dielectric constants. Using quantum chemical calculations, we simulate ESAs of the lowest triplet states, highlighting the contribution of only 3CT and donor-moiety 3LE states to spectral features, with no strong evidence for a low-lying acceptor-centered 3LE. Thus, our work provides a blueprint for understanding the role of triplet excited states in CMAs which will enable further intelligent optimization of this promising class of materials.

Increase in nephrology advanced trainee numbers in Australia and associated reduction in clinical exposure over the past decade.

BACKGROUND: Advanced training in nephrology should provide broad experience in all aspects of nephrology. In Australia, the Specialist Advisory Committee in Nephrology oversees nephrology training, and recent increases in advanced trainee numbers have led to concern about dilution of training experience. No study has examined variations in clinical exposure for nephrology trainees in Australia. AIM: To assess the changes in nephrology advanced training in Australia with respect to trainee numbers and exposure to patients and procedures over the past 10 years. METHODS: A retrospective study was performed by obtaining all available Royal Australasian College of Physician supervisor reports from 2000 to 2010 to determine differences in clinical exposure and procedures performed by nephrology trainees. RESULTS: Five hundred and forty-two reports were reviewed involving 208 nephrology trainees in Australia across 53 different training sites. In 2000, 22 trainees were undertaking a core clinical year of training. Trainee numbers have steadily risen from 33 in 2004 to 84 in 2010. The greatest increases have occurred in New South Wales, Victoria and Queensland (sixfold, threefold and fivefold increases respectively). Trainee exposure to dialysis patients has gradually decreased in the past decade. The average number per trainee per year in 2000 compared with 2010 were 66 versus 43 (P = 0.02) and 28 versus 16 (P = 0.01) for haemodialysis and peritoneal dialysis respectively. Acute kidney injury cases per trainee showed a gradual nonsignificant reduction over time and average procedural numbers per trainee decreased significantly from 2000 to 2010 with fewer temporary dialysis catheters inserted per year (39 vs 10, P < 0.01) and fewer renal biopsies performed per year (65 vs 41, P < 0.01). The proportion of trainees working in a hospital that does not provide exposure to acute transplantation has steadily increased from 15% in 2003 to 44% in 2010. CONCLUSIONS: There has been a dramatic and significant increase in nephrology advanced trainee numbers over the past decade at a more rapid rate than the growth in dialysis and transplant patient numbers. This study suggests that training experience has diminished over the past decade and supports a 3-year core clinical nephrology training programme in Australia.

Randomized controlled trial of sirolimus for renal transplant recipients at high risk for nonmelanoma skin cancer.

Sirolimus has antineoplastic effects and may reduce skin cancer rates in kidney transplant patients. This prospective, multicenter, randomized, open-label, controlled trial randomized 86 kidney transplant recipients (≥1 year posttransplant) with history of nonmelanoma skin cancer (NMSC) to continue calcineurin inhibitor (CNI) or convert to sirolimus. Patients were stratified by number of NMSC lesions (0-5, 6-20) in previous year. Primary end point was number of biopsy-confirmed new NMSC lesions per patient-year. Yearly NMSC rate was significantly lower with sirolimus (1.31 vs. 2.48 lesions/patient-year; p = 0.022). Squamous cell carcinoma occurred at a lower rate in the sirolimus versus CNI group (p = 0.038); basal cell carcinoma rate was similar in both. A lower proportion of patients receiving sirolimus developed new or recurrent NMSC (56.4% vs. 80.9%; p = 0.015) or new squamous cell carcinoma (41.0% vs. 70.2%; p = 0.006). No sirolimus patients and one CNI continuation patient experienced acute rejection. Incidence of treatment-emergent adverse events was similar between groups; however, discontinuation rates related to adverse events were significantly higher with sirolimus (46.2% vs. 0%; p < 0.001). In kidney transplant recipients with history of NMSC, conversion from CNI to sirolimus reduced rates of NMSC, without increasing acute rejection risk.

The impact of prolonged exposure therapy on social support and PTSD symptoms.

BACKGROUND: Posttraumatic stress disorder (PTSD) results in high costs to society, particularly among military personnel. Much is known about PTSD treatments-such as exposure therapies-and their outcomes, but less is known about how treatment might impact social support and PTSD symptoms over the course of treatment. METHODS: In the current study, soldiers with PTSD (N = 162) were randomized to complete prolonged exposure therapy (either with or without virtual reality) or a waitlist control condition. We examined the impact of treatment on perceived social support as a secondary treatment outcome, as well as the associations between social support and PTSD symptoms over time. RESULTS: Exposure therapy increased perceived social support at the end of treatment compared to waitlist control, ß = 0.43, 95% CI [0.13, 0.73]. Multigroup structural equation modeling using a cross-lagged panel design provided evidence that perceived social support was an antecedent of PTSD symptom improvement for participants engaging in treatment, but not for participants in the waitlist control. Treatment effects on change in PTSD symptoms was mediated by change in perceived social support (B = 1.10, 95% CI [0.20, 3.05]). LIMITATIONS: The results should be considered in light of limitations, including the characteristics of the sample of active duty soldiers, the measurement of social support, and missingess over the course of the study. CONCLUSIONS: These results suggest that increased perceived social support is a secondary outcome of exposure therapy and may be one pathway through which treatment reduces PTSD symptoms.

Highly efficient blue organic light-emitting diodes based on carbene-metal-amides.

Carbene-metal-amides are soluble and thermally stable materials which have recently emerged as emitters in high-performance organic light-emitting diodes. Here we synthesise carbene-metal-amide photoemitters with CF3-substituted ligands to show sky-blue to deep-blue photoluminescence from charge-transfer excited states. We demonstrate that the emission colour can be adjusted from blue to yellow and observe that the relative energies of charge transfer and locally excited triplet states influence the performance of the deep-blue emission. High thermal stability and insensitivity to aggregation-induced luminescence quenching allow us to fabricate organic light-emitting diodes in both host-free and host-guest architectures. We report blue devices with a peak external quantum efficiency of 17.3% in a host-free emitting layer and 20.9% in a polar host. Our findings inform the molecular design of the next generation of stable blue carbene-metal-amide emitters.

Cutaneous manifestations of cytomegalovirus disease in renal transplant recipients: a case series.

Cytomegalovirus (CMV) is an important and well-described opportunistic virus in the immunocompromised host, with infection occurring mainly after the first month in the new renal transplant recipient. CMV can present as primary infection, reinfection, or reactivation of latent disease. It is capable of protean manifestations. Cutaneous manifestations are variable, rare, and diagnosis often delayed. We present 3 cases of cutaneous CMV disease in renal transplant recipients. Manifestations in our patients included ulceration of the tongue and perianal areas, facial petechiae, and nodular lesion involving the ear. This case series serves to highlight the importance of early skin biopsy in the diagnosis and management of cutaneous CMV disease.

Prevalence and correlates of postpartum depression in first-time mothers.

The prevalence and correlates of postpartum depression were examined in a large (N = 1,033) sample of married, primiparous, middle-class mothers of full-term, healthy infants; 9.3% met modified Research Diagnostic Criteria for depression. However, 39% of the nondepressed women also reported at least 1 somatic symptom. Depressed women whose symptoms were current obtained elevated scores on the Center for Epidemiological Studies-Depression scale, as did some women who did not meet depression criteria. Depressed women different from nondepressed women on several socioeconomic status indicators and the occurrence of obstetric complications, even in this low-risk sample. These data have implications for the assessment of depression in postpartum women.

Postpartum depression and postpartum adaptation: overlapping constructs?

In order to examine the course of normal postpartum adjustment compared to the symptomatology of postpartum depression, 25 postpartum women who met Research Diagnostic Criteria for either major or minor depression were compared to 24 non-depressed postpartum women. The Schedule for Affective Disorders and Schizophrenia (SADS) and the Beck Depression Inventory (BDI) were administered to all subjects. Results suggest that sleep disturbances and loss of sexual interest are common concomitants of normal postpartum adjustment. A discriminant function analysis indicated that the cognitive-affective symptoms of loss of energy, guilt, difficulties in concentration, and loss of interest in usual activities discriminated between depressed and non-depressed women most efficiently. Finally, there was a lack of concordance between the BDI and the SADS interviews, which suggests that the BDI may not be an appropriate instrument for diagnosing depression in a postpartum sample.

Infant affective responses to mother's still face at 6 months differentially predict externalizing and internalizing behaviors at 18 months.

This study investigated (a) stability and change in infant affective responses to the still-face interaction, (b) whether maternal depression affected infant responses, and (c) whether responses to the still-face interaction predicted toddler problem behaviors. Infants (63 girls and 66 boys) of European American mothers (67 depressed and 62 nondepressed) were observed in the still-face interaction at 2, 4, and 6 months. Affect and gaze were coded on a 1-s time base. There were stable individual differences in gazing away and in rates of negative affect. Developmental change occurred only for gazing away, which increased. At 18 months, infants who failed to smile at 6 months in the still-face interaction showed more externalizing-type behaviors than did other toddlers. Infants who failed to cry at 6 months showed fewer internalizing-type behaviors. Mothers' current depressive symptoms and infants' earlier responses to the still-face interaction made independent, comparable contributions to problem behaviors at 18 months.

Mothers' affective behavior with infant siblings: stability and change.

To evaluate within-family differences in maternal affective behavior toward siblings, face-to-face interactions were observed between 39 mothers and their firstborn and second-born infants at 2 months of age. Mother and infant affect was coded on a 1-s time base with behavioral descriptors. Mothers were more positive with second-born infants, and second-born infants were more positive than were firstborns. The siblings' affective behaviors were unrelated, but maternal positive affect was both moderately stable between siblings and correlated with each infant's affect. Thus, in the context of stable individual differences in maternal positive affect, siblings experienced unique affective interactions with their mothers as early as 2 months.

Oral versus intravenous iron supplementation in peritoneal dialysis patients.

The vast majority of erythropoietin (EPO)-treated peritoneal dialysis (PD) patients require iron supplementation. Most authors and clinical practice guidelines recommend primary oral iron supplementation in PD patients because it is more practical and less expensive. However, numerous studies have clearly demonstrated that oral iron therapy is unable to maintain EPO-treated PD patients in positive iron balance. Once patients become iron-deficient, intravenous iron administration has been found to more effectively augment iron stores and hematologic response than does oral therapy. We recently performed a prospective, cross-over trial in 28 iron-replete PD patients and showed that twice-monthly outpatient iron polymaltose infusions (200 mg) were a practical and safe alternative to oral iron. That treatment produced significant increases in hemoglobin concentration and body iron stores. The additional expense of intravenous iron therapy was completely offset by reductions in EPO dosage. Careful monitoring of iron stores is important in patients receiving intravenous iron supplementation in view of epidemiologic links with infection and cardiovascular disease. Nevertheless, a growing body of evidence suggests that, as has been found for hemodialysis patients, intravenous iron therapy is superior to oral iron supplementation in EPO-treated PD patients.

Peritoneal homocysteine clearance is inefficient in peritoneal dialysis patients.

OBJECTIVES: To investigate the degree and the determinants of peritoneal homocysteine (Hcy) clearance and to compare measured Hcy clearance with the Hcy clearance predicted based on molecular weight (MW). DESIGN: Cross-sectional observational analysis. SETTING: Tertiary care institutional dialysis center. PATIENTS: Sixty-five stable peritoneal dialysis (PD) patients. OUTCOME MEASURES: Fasting blood and 24-hour pooled dialysate effluents were collected for determination of peritoneal clearances of Hcy (CpHcy), urea (CpUr), and creatinine (CpCr). The dialysate-to-plasma creatinine ratio at 4 hours (D/P Cr 4 h) and levels of red cell folate, B12, ferritin, and C-reactive protein (CRP) were measured concurrently. Observed CpHcy was compared with predicted clearance, based on Hcy plasma protein binding and the relative molecular weights of Hcy, urea, and creatinine. RESULTS: Plasma concentrations of Hcy averaged 24.6 +/- 1.1 micromol/L and were elevated above the upper limit of normal in 59 (91%) patients. The mean dialysate concentration of Hcy was 2.9 +/- 0.3 micromol/L, equating to a daily peritoneal elimination of 34.6 +/- 3.6 micromol. Observed CpHcy was closely approximated by predicted CpHcy (8.7 +/- 0.6 L/week/1.73 m2 vs 9.0 +/- 0.3 L/week/1.73 m2 respectively, p = 0.55). Patients maintained on automated PD (n = 5) had a CpHcy similar to that of patients treated with continuous ambulatory peritoneal dialysis (8.9 +/- 1.0 L/week/1.73 m2 vs 8.7 +/- 0.6 L/week/1.73 m2, p = 0.92). The CpHcy was significantly correlated with C-reactive protein (CRP), D/P creatinine, CpUr, CpCr, and peritoneal protein loss, but not with plasma Hcy, albumin, B12, ferritin, age, dialysis duration, peritonitis episodes, or daily dialysate effluent volume. By multivariate analysis, the only variables that remained significant independent predictors of CpHcy were CRP and D/P Cr 4 h. High and high-average transporters had a higher CpHcy than low and low-average transporters (9.7 +/- 0.8 L/week/1.73 m2 vs 7.0 +/- 0.7 L/week/1.73 m2, p < 0.05), despite comparably elevated plasma Hcy concentrations [25.2 +/- 1.5 micromol/L vs 23.4 +/- 1.6 micromol/L, p = nonsignificant (NS)]. CONCLUSIONS: Elevated plasma concentrations of Hcy are not efficiently reduced by PD. The relatively low peritoneal clearance of Hcy is largely accounted for by a high degree of plasma protein binding and is significantly influenced by peritoneal membrane permeability.

Is obesity a favorable prognostic factor in peritoneal dialysis patients?

OBJECTIVE: To determine the influence of an elevated body mass index (BMI) on cardiovascular outcomes and survival in peritoneal dialysis (PD) patients. DESIGN: Prospective, observational study of a prevalent PD cohort at a single center. SETTING: Tertiary care institutional dialysis center. PATIENTS: The study included all patients with a BMI of at least 20 who had been receiving PD for at least 1 month as of 31 January 1996 (n = 43). Patients were classified as overweight [BMI > 27.5; mean +/- standard error of mean (SEM): 32.1 +/- 1.1; n = 14] or normal weight (BMI 20-27.5; mean +/- SEM: 23.8 +/- 0.4; n = 29). OUTCOME MEASURES: Patient survival and adverse cardiovascular events (myocardial infarction, congestive cardiac failure, cerebrovascular accident, and symptomatic peripheral vascular disease) were recorded over a 3-year period. RESULTS: At baseline, no significant differences were seen between the groups in clinical, biochemical, nutritional, or echocardiographic parameters, except for a lower dietary protein intake (0.97 +/- 0.10 g/kg/day vs 1.44 +/- 0.10 g/kg/day, p = 0.004) and a higher proportion of well-nourished patients by subjective global assessment (100% vs 72%, p < 0.05) in the overweight group. After 3 years of follow-up, 29% of overweight patients and 69% of normal-weight patients had died (p < 0.05). Using a Cox proportional hazards model, a BMI greater than 27.5 was shown to be an independent positive predictor of patient survival, with an adjusted hazard ratio (HR) of 0.09 [95% confidence interval (CI): 0.01-0.85; p < 0.05]. However, being overweight did not significantly influence myocardial infarction-free survival (adjusted HR: 0.33; 95% CI: 0.07-1.48; p = 0.15) or combined adverse cardiovascular event-free survival (adjusted HR: 0.67; 95% CI: 0.23-1.93; p = 0.46). CONCLUSIONS: Obesity conferred a significant survival advantage in our PD population. Obese patients should therefore not be discouraged from receiving PD purely on the basis of BMI. Moreover, maintaining a higher-than-average BMI to preserve "nutritional reserve" may help to reduce the mortality and morbidity rates associated with PD.

Hard-to-manage preschool boys: externalizing behavior, social competence, and family context at two-year followup.

Boys, identified as hard to manage in preschool, were followed up 2 years after initial assessment. Mothers, fathers, and teachers continued to rate hard-to-manage boys as having more problems with attention and impulse control, and as more oppositional, than comparison boys who had been problem-free at intake; problem boys also were rated as less socially competent by all three informants. Differences in severity were apparent as a function of initial referral source. Boys identified as showing significant problems by at least two informants (28% of the problem boys) were especially low in social competence and their mothers reported more symptoms of depression and parenting stress. Family adversity, lower IQ, and severity of symptoms at intake discriminated boys with continuing problems from those with less serious difficulties at followup. Control boys with potentially emerging problems were characterized by more family problems than the remaining control boys. Implications for the development of problems in young children are discussed.

Social perspective-taking and teacher ratings of peer interaction in hyperactive boys.

Hyperactive and matched control boys at two age levels were compared on teacher ratings of peer interaction and three measures of social perspective-taking. The teachers' ratings of peer interaction discriminated between the hyperactive children and their controls. In addition, a significant interaction effect indicated that teachers rated the older hyperactive group as more deviant with peers than both their younger hyperactive counterparts and their age-matched controls. In a structured laboratory setting, the hyperactive children did not differ from control children on the three measures of social perspective-taking. The perspective-taking measures did, however, show differences across age groups. Implications for treatment are examined.

Some psychological correlates of generalized and focal epilepsy in children.

School-aged children with two types of epilepsy, generalized and focal, were compared with normal children of the same age, sex, and IQ on measures of cognitive style, attention, motor control, and behavioral pathology. Epileptic children were found to employ less efficient cognitive strategies and to have longer reaction times and poorer control of fine motor movements than have normal children. Children with generalized epilepsy were more impaired than were normal children when sustained motor performance was required. Mothers of children with generalized epilepsy reported more behavior problems than did control mothers on an objective checklist. These results suggest special educational methods for the treatment and education of epileptic children.

Continuities in maternal reports and child behaviors over time in hyperactive and comparison groups.

Maternal reports, observations of nursery and elementary school behavior, and teacher ratings of problems were available for hyperactive and control children who had participated in a longitudinal study. This paper examines consistencies in maternal reports and child behaviors over time, and their relationship to teacher ratings in elementary school. Maternal reports of infant sleep difficulties were related to maternal ratings of hyperactivity at 4 1/2 and 6 1/2 years. Maternal ratings of activity at 4 1/2 were predictive of 6 1/2-year ratings of hyperactivity and conduct problems. In addition, behavior in a research nursery at 4 1/2 predicted teacher ratings of problems and classroom behavior in grade two. Hyperactive preschoolers who left the table most during structured activities were more often out-of-seat and off-task in school. Controls who were more aggressive in the nursery were more disruptive in the classroom. These data indicate continuities in both maternal reports and child behaviors.

A multidimensional assessment of parent-identified behavior problem toddlers.

Sixty-eight 2- and 3-year-olds (46 parent-referred, 22 controls) participating in an identification, assessment, and follow-up study of hyperactivity and related behavior problems were evaluated on parent-report, observational, and cognitive measures. Referred youngsters were described by both parents as more active, inattentive, difficult to discipline, and aggressive with peers than were controls. Mothers of referred children also reported a more difficult infancy period. Laboratory assessments confirmed parental reports of current problems. Referred children shifted activities more during free play, were more active and inattentive during structured tasks, and made more impulsive responses on a delay task than did controls. Discriminant function analysis indicated that parental ratings of activity paired with laboratory measures of sustained attention and impulsivity correctly classified 88% of the sample. These data suggest that the core symptoms of hyperactivity can be identified in very young children, although their prognostic significance remains to be determined.

Hard-to-manage preschool boys: family context and the stability of externalizing behavior.

Preschool boys identified by their teachers as active, inattentive, and impulsive (N = 42) were compared with matched classroom controls (N = 43) and with parent-identified problem boys (N = 27) on measures of family functioning often associated with children's problem behaviors, including family history of psychopathology, stressful life events, and family composition. Teacher-identified and parent-identified problem boys did not differ on measures of family adversity, and both groups came from less well functioning families than comparison boys. Mothers of problem boys, regardless of referral source, were more negative and controlling toward their sons when observed in a compliance task. Children's problem behaviors were moderately stable over a one-year follow-up period; initial symptom levels, maternal self-reported depression, and negative maternal control predicted follow-up ratings of externalizing problems.

Parent-identified problem preschoolers: mother-child interaction during play at intake and 1-year follow-up.

Parent-referred 2- and 3-year-olds and controls, participating in a longitudinal study of hyperactivity and related behavior problems, were observed with their mothers during play at an initial assessment and a 1-year follow-up. Mothers of problem children provided more redirection initially and made more negative control statements at follow-up than mothers of controls; problem youngsters tended to play more aggressively. Sex differences were prominent. Mothers of boys, regardless of referral status, were more directive at the initial assessment; their sons were less cooperative and somewhat more aggressive in their play. Maternal involvement in play decreased over time, possibly as a response to developmental changes in children's play. Group by time interactions indicated that mothers of control children provided fewer negative control statements at follow-up relative to mothers of problem children and to their own levels at the first assessment; mothers of problem youngsters redirected their children less than they had initially. Mothers of boys were also less directive at follow-up relative to their initial levels. Situational and developmental factors are discussed briefly.