Analyzing the Catalytic Role of Asp97 in the Methionine Aminopeptidase from \u3cem\u3eEscherichia coli\u3c/em\u3e

An active site aspartate residue, Asp97, in the methionine aminopeptidase (MetAPs) from Escherichia coli (EcMetAP-I) was mutated to alanine, glutamate, and asparagine. Asp97 is the lone carboxylate residue bound to the crystallographically determined second metal-binding site in EcMetAP-I. These mutant EcMetAP-I enzymes have been kinetically and spectroscopically characterized. Inductively coupled plasma–atomic emission spectroscopy analysis revealed that 1.0 ± 0.1 equivalents of cobalt were associated with each of the Asp97-mutated EcMetAP-Is. The effect on activity after altering Asp97 to alanine, glutamate or asparagine is, in general, due to a ∼ 9000-fold decrease in kca towards Met-Gly-Met-Met as compared to the wild-type enzyme. The Co(II) d–d spectra for wild-type, D97E and D97A EcMetAP-I exhibited very little difference in form, in each case, between the monocobalt(II) and dicobalt(II) EcMetAP-I, and only a doubling of intensity was observed upon addition of a second Co(II) ion. In contrast, the electronic absorption spectra of [Co_(D97N EcMetAP-I)] and [CoCo(D97N EcMetAP-I)] were distinct, as were the EPR spectra. On the basis of the observed molar absorptivities, the Co(II) ions binding to the D97E, D97A and D97N EcMetAP-I active sites are pentacoordinate. Combination of these data suggests that mutating the only nonbridging ligand in the second divalent metal-binding site in MetAPs to an alanine, which effectively removes the ability of the enzyme to form a dinuclear site, provides a MetAP enzyme that retains catalytic activity, albeit at extremely low levels. Although mononuclear MetAPs are active, the physiologically relevant form of the enzyme is probably dinuclear, given that the majority of the data reported to date are consistent with weak cooperative binding

Online cognitive behaviour training for the prevention of postnatal depression in at-risk mothers: a randomised controlled trial protocol

Background Postnatal depression (PND) is the most common disorder of the puerperium with serious consequences for both mother and child if left untreated. While there are effective treatments, there are many barriers for new mothers needing to access them. Prevention strategies may offer a more acceptable means of addressing the problem. Internet interventions can help overcome some barriers to reducing the impact of PND. However, to date there are no published studies that investigate the efficacy of internet interventions for the prevention of PND. Methods/Design The proposed study is a two-arm double blind randomised controlled trial. 175 participants will be recruited in the immediate postnatal period at an Australian community hospital. Women who meet inclusion criteria (internet access, email address, telephone number, over 18, live birth, fluent English) will complete the Edinburgh Postnatal Depression Scale (EPDS). Those with a score above 9 will undertake the Structured Clinical Interview for DSM Disorders (SCID). Those with a clinical diagnosis of depression, or a lifetime diagnosis of bipolar disorder or psychosis on the SCID will be excluded. Following completion of the baseline battery women will be randomised using a computer-generated algorithm to either the intervention or control condition. The intervention will consist of 5 modules of automated, interactive cognitive behaviour training (CB training), completed weekly with email reminders. The control will replicate the level of contact participants experience with the intervention, but the content will be of a general health nature. Participants will complete questionnaires immediately post-intervention (6 weeks) and 3-, 6- and 12 months follow-up. There will also be a second SCID delivered via telephone at 6 months. We hypothesise that relative to the control group, the intervention group will show a greater reduction in postnatal distress on the EPDS (primary outcome measure). We also hypothesise that the intervention group will demonstrate lower levels of anxiety and stress and higher levels of parenting confidence than the control group following intervention and/or follow-up. Discussion The proposed study addresses a number of limitations of earlier trials

Protocol for a randomised controlled trial investigating the effectiveness of an online e health application for the prevention of Generalised Anxiety Disorder

BACKGROUND Generalised Anxiety Disorder (GAD) is a highly prevalent psychiatric disorder. Effective prevention in young adulthood has the potential to reduce the prevalence of the disorder, to reduce disability and lower the costs of the disorder to the community. The present trial (the WebGAD trial) aims to evaluate the effectiveness of an evidence-based online prevention website for GAD. METHODS/DESIGN The principal clinical question under investigation is the effectiveness of an online GAD intervention (E-couch) using a community-based sample. We examine whether the effect of the intervention can be maximised by either human support, in the form of telephone calls, or by automated support through emails. The primary outcome will be a reduction in symptoms on the GAD-7 in the active arms relative to the non active intervention arms. DISCUSSION The WebGAD trial will be the first to evaluate the use of an internet-based cognitive behavioural therapy (CBT) program contrasted with a credible control condition for the prevention of GAD and the first formal RCT evaluation of a web-based program for GAD using community recruitment. In general, internet-based CBT programs have been shown to be effective for the treatment of other anxiety disorders such as Post Traumatic Stress Disorder, Social Phobia, Panic Disorder and stress in clinical trials; however there is no evidence for the use of internet CBT in the prevention of GAD. Given the severe shortage of therapists identified in Australia and overseas, and the low rates of treatment seeking in those with a mental illness, the successful implementation of this protocol has important practical outcomes. If found to be effective, WebGAD will provide those experiencing GAD with an easily accessible, free, evidence-based prevention tool which can be promoted and disseminated immediately

External validation of the Vulnerable Elder\u27s Survey for predicting mortality and emergency admission in older community-dwelling people: a prospective cohort study.

BACKGROUND: Prospective external validation of the Vulnerable Elder\u27s Survey (VES-13) in primary care remains limited. The aim of this study is to externally validate the VES-13 in predicting mortality and emergency admission in older community-dwelling adults. METHODS: Design: Prospective cohort study with 2 years follow-up (2010-2012). SETTING: 15 General Practices (GPs) in the Republic of Ireland. PARTICIPANTS: n = 862, aged ≥70 years, community-dwellers Exposure: VES-13 calculated at baseline, where a score of ≥3 denoted high risk. OUTCOMES: i) Mortality; ii) ≥1 Emergency admission and ≥1 ambulatory care sensitive (ACS) admission over 2 years. STATISTICAL ANALYSIS: Descriptive statistics, model discrimination (c-statistic) and sensitivity/specificity. RESULTS: Of 862 study participants, a total of 246 (38%) were classified as vulnerable at baseline. Fifty-three (6%) died during follow-up and 246 (29%) had an emergency admission. At the VES-13 cut-point of ≥3 denoting high-risk model discrimination was poor for mortality (c-statistic: 0.61 (95% CI 0.54, 0.67), ≥1 emergency admission (c-statistic: 0.59 (95% CI 0.56, 0.63) and ≥1 ACS emergency admission (c-statistic: 0.63 (95% CI 0.60, 0.67). CONCLUSIONS: In this study the VES-13 demonstrated relatively limited predictive accuracy in predicting mortality and emergency admission. External validation studies examining the tool in different health settings and healthier populations are needed and represent an interesting area for future research

Impact of Potentially Inappropriate Prescribing on Adverse Drug Events, Health Related Quality of Life and Emergency Hospital Attendance in Older People Attending General Practice: A Prospective Cohort Study.

BACKGROUND: Potentially inappropriate prescribing (PIP) describes medications where risk generally outweighs benefit for older people. Cross-sectional studies suggest an association between PIP and poorer health outcomes but there is a paucity of prospective cohort studies. This study investigates the longitudinal association of PIP with adverse drug events (ADEs), health related quality of life, and accident \u26 emergency visits. METHODS: Study design: Two-year (2010-2012) prospective cohort study (n = 904, ≥70 years, community-dwelling) with linked pharmacy dispensing data. EXPOSURE: Baseline PIP: Screening Tool for Older Persons potentially Inappropriate Prescriptions (STOPP) and Beers 2012 applied 12 months prior. STUDY OUTCOMES: ADEs (patient interview), health related quality of life (EQ-5D-3L: patient questionnaire), and accident \u26 emergency visits (general practice medical record review). STATISTICAL ANALYSIS: Descriptive statistics: Poisson (incidence rate ratio [95% confidence interval [CI]], linear regression models [regression coefficient [95% CI]], and logistic [odds ratio [OR] [95% CI]). RESULTS: Of 791 participants eligible for follow-up, 673 (85%) returned a questionnaire and 605 (77%) also completed an ADE interview. Baseline STOPP PIP prevalence was 40% and 445 (74%) patients reported ≥1 ADE at follow-up. In multivariable analysis, ≥2 STOPP PIP was associated with ADEs (adjusted incidence rate ratio: 1.29 [95% CI 1.03, 1.85; p = .03]; poorer health related quality of life [adjusted regression coefficient: -0.11 [95% CI -0.16, -0.06; p \u3c .001]]; and, ≥1 accident \u26 emergency visit [adjusted OR: 1.85 [95% CI 1.06, 3.24; p = .03]]). Baseline Beers 2012 prevalence was 26% and there was no association with adverse health outcomes in multivariable analysis. CONCLUSIONS: Older community-dwelling people, prescribed ≥2 STOPP PIP are more likely to report ADEs, poorer health related quality of life and attend the accident \u26 emergency department over 2-year follow-up

Comparison of count-based multimorbidity measures in predicting emergency admission and functional decline in older community-dwelling adults: a prospective cohort study.

OBJECTIVES: Multimorbidity, defined as the presence of 2 or more chronic medical conditions in an individual, is associated with poorer health outcomes. Several multimorbidity measures exist, and the challenge is to decide which to use preferentially in predicting health outcomes. The study objective was to compare the performance of 5 count-based multimorbidity measures in predicting emergency hospital admission and functional decline in older community-dwelling adults attending primary care. SETTING: 15 general practices (GPs) in Ireland. PARTICIPANTS: n=862, ≥70 years, community-dwellers followed-up for 2 years (2010-2012). Exposure at baseline: Five multimorbidity measures (disease counts, selected conditions counts, Charlson comorbidity index, RxRisk-V, medication counts) calculated using GP medical record and linked national pharmacy claims data. PRIMARY OUTCOMES: (1) Emergency admission and ambulatory care sensitive (ACS) admission (GP medical record) and (2) functional decline (postal questionnaire). STATISTICAL ANALYSIS: Descriptive statistics and measure discrimination (c-statistic, 95% CIs), adjusted for confounders. RESULTS: Median age was 77 years and 53% were women. Prevalent rates ranged from 37% to 91% depending on which measure was used to define multimorbidity. All measures demonstrated poor discrimination for the outcome of emergency admission (c-statistic range: 0.62, 0.65), ACS admission (c-statistic range: 0.63, 0.68) and functional decline (c-statistic range: 0.55, 0.61). Medication-based measures were equivalent to diagnosis-based measures. CONCLUSIONS: The choice of measure may have a significant impact on prevalent rates. Five multimorbidity measures demonstrated poor discrimination in predicting emergency admission and functional decline, with medication-based measures equivalent to diagnosis-based measures. Consideration of multimorbidity in isolation is insufficient for predicting these outcomes in community settings

Demographic and psychosocial predictors of major depression and generalised anxiety disorder in Australian university students

Abstract Background Few studies have examined modifiable psychosocial risk factors for mental disorders among university students, and of these, none have employed measures that correspond to clinical diagnostic criteria. The aim of this study was to examine psychosocial and demographic risk factors for major depression and generalised anxiety disorder (GAD) in a sample of Australian university students. Methods An anonymous web-based survey was distributed to undergraduate and postgraduate students at a mid-sized Australian university. A range of psychosocial and demographic risk factors were measured, and logistic regression models were used to examine significant predictors of major depression and GAD. Results A total of 611 students completed the survey. The prevalence of major depression and GAD in the sample was 7.9 and 17.5 %, respectively. In terms of demographic factors, the risk of depression was higher for students in their first year of undergraduate study, and the risk of GAD was higher for female students, those who moved to attend university, and students experiencing financial stress. In terms of psychosocial factors, students with experience of body image issues and lack of confidence were at significantly greater risk of major depression, and feeling too much pressure to succeed, lack of confidence, and difficulty coping with study was significantly associated with risk of GAD. Conclusions University students experience a range of unique psychosocial stressors that increase their risk of major depression and GAD, in addition to sociodemographic risk factors. It is important to examine psychosocial factors, as these are potentially modifiable and could be the focus of university-specific mental health interventions.This project was resourced by the Young and Well CRC (youngandwellcrc.org.au). The Young and Well CRC is established under the Australian Government’s Cooperative Research Centres Program. KMG is supported by a National Health and Medical Research Council Fellowship (No.1059620)

The ANU WellBeing study: a protocol for a quasi-factorial randomised controlled trial of the effectiveness of an Internet support group and an automated Internet intervention for depression

BACKGROUND Recent projections suggest that by the year 2030 depression will be the primary cause of disease burden among developed countries. Delivery of accessible consumer-focused evidenced-based services may be an important element in reducing this burden. Many consumers report a preference for self-help modes of delivery. The Internet offers a promising modality for delivering such services and there is now evidence that automated professionally developed self-help psychological interventions can be effective. By contrast, despite their popularity, there is little evidence as to the effectiveness of Internet support groups which provide peer-to-peer mutual support. METHODS/DESIGN Members of the community with elevated psychological distress were randomised to receive one of the following: (1) Internet Support Group (ISG) intervention, (2) a multi-module automated psychoeducational and skills Internet Training Program (ITP), (3) a combination of the ISG and ITP, or (4) an Internet Attention Control website (IAC) comprising health and wellbeing information and question and answer modules. Each intervention was 12 weeks long. Assessments were conducted at baseline, post-intervention, 6 and 12 months to examine depressive symptoms, social support, self-esteem, quality of life, depression literacy, stigma and help-seeking for depression. Participants were recruited through a screening postal survey sent to 70,000 Australians aged 18 to 65 years randomly selected from four rural and four metropolitan regions in Australia. DISCUSSION To our knowledge this study is the first randomised controlled trial of the effectiveness of a depression ISG. TRIAL REGISTRATION Current Controlled Trials ISRCTN65657330.This study was funded by a National Health and Medical Research Council Project Grant 471435 to KG, HC and AM. KG is supported by NHMRC Fellowship No. 525413 and HC is supported by Fellowship No. 525411

Risk prediction models to predict emergency hospital admission in community-dwelling adults: a systematic review.

BACKGROUND: Risk prediction models have been developed to identify those at increased risk for emergency admissions, which could facilitate targeted interventions in primary care to prevent these events. OBJECTIVE: Systematic review of validated risk prediction models for predicting emergency hospital admissions in community-dwelling adults. METHODS: A systematic literature review and narrative analysis was conducted. Inclusion criteria were as follows; POPULATION: community-dwelling adults (aged 18 years and above); Risk: risk prediction models, not contingent on an index hospital admission, with a derivation and ≥1 validation cohort; PRIMARY OUTCOME: emergency hospital admission (defined as unplanned overnight stay in hospital); STUDY DESIGN: retrospective or prospective cohort studies. RESULTS: Of 18,983 records reviewed, 27 unique risk prediction models met the inclusion criteria. Eleven were developed in the United States, 11 in the United Kingdom, 3 in Italy, 1 in Spain, and 1 in Canada. Nine models were derived using self-report data, and the remainder (n=18) used routine administrative or clinical record data. Total study sample sizes ranged from 96 to 4.7 million participants. Predictor variables most frequently included in models were: (1) named medical diagnoses (n=23); (2) age (n=23); (3) prior emergency admission (n=22); and (4) sex (n=18). Eleven models included nonmedical factors, such as functional status and social supports. Regarding predictive accuracy, models developed using administrative or clinical record data tended to perform better than those developed using self-report data (c statistics 0.63-0.83 vs. 0.61-0.74, respectively). Six models reported c statistics of \u3e0.8, indicating good performance. All 6 included variables for prior health care utilization, multimorbidity or polypharmacy, and named medical diagnoses or prescribed medications. Three predicted admissions regarded as being ambulatory care sensitive. CONCLUSIONS: This study suggests that risk models developed using administrative or clinical record data tend to perform better. In applying a risk prediction model to a new population, careful consideration needs to be given to the purpose of its use and local factors