Identifying Ligand Binding Conformations of the β2-Adrenergic Receptor by Using Its Agonists as Computational Probes

Recently available G-protein coupled receptor (GPCR) structures and biophysical studies suggest that the difference between the effects of various agonists and antagonists cannot be explained by single structures alone, but rather that the conformational ensembles of the proteins need to be considered. Here we use an elastic network model-guided molecular dynamics simulation protocol to generate an ensemble of conformers of a prototypical GPCR, β2-adrenergic receptor (β2AR). The resulting conformers are clustered into groups based on the conformations of the ligand binding site, and distinct conformers from each group are assessed for their binding to known agonists of β2AR. We show that the select ligands bind preferentially to different predicted conformers of β2AR, and identify a role of β2AR extracellular region as an allosteric binding site for larger drugs such as salmeterol. Thus, drugs and ligands can be used as "computational probes" to systematically identify protein conformers with likely biological significance. © 2012 Isin et al

Beyond handover: supporting awareness for continuous coverage

Abstract Hospitals are required to operate as a continuous system because patient care cannot be temporarily suspended and handover is seen as a key method for enabling this. This paper reports a study of handover in a medical admissions unit. We draw on the notion of awareness as conceptualised within the Computer Supported Cooperative Work literature to explore the role played by a variety of cognitive artifacts in supporting continuous coverage. While such awareness is typically characterised as being ‘effortless’, our study reveals that maintaining awareness in a context such as the medical admissions unit is effortful due to invisible work. We suggest that the notion of awareness is beneficial for exploring the practices of continuous coverage because it moves attention away from the moment of handover, instead encouraging consideration of the variety of practices through which clinicians display their work to, and monitor the work of, colleagues on different shifts. We argue that efforts to support continuous coverage should focus on improving awareness by increasing the visibility of information

Memory development: implications for adults recalling childhood experiences in the courtroom

Adults frequently provide compelling, detailed accounts of early childhood experiences in the courtroom. Judges and jurors are asked to decide guilt or innocence based solely on these decades-old memories using 'common sense' notions about memory. However, these notions are not in agreement with findings from neuroscientific and behavioural studies of memory development. Without expert guidance, judges and jurors may have difficulty in properly adjudicating the weight of memory evidence in cases involving adult recollections of childhood experiences

Long-Term SGRQ Stability in a Cohort of Individuals with Alpha-1 Antitrypsin Deficiency-Associated Lung Disease

Radmila Choate,1 Kristen E Holm,2,3 Robert A Sandhaus,2,3 David M Mannino,4 Charlie Strange3,5 1University of Kentucky College of Public Health, Lexington, Kentucky, USA; 2Department of Medicine, National Jewish Health, Denver, Colorado, USA; 3Alphanet, Inc., Coral Gables, Florida, USA; 4University of Kentucky College of Medicine, Lexington, Kentucky, USA; 5Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, South Carolina, USACorrespondence: Radmila Choate, University of Kentucky College of Public Health, Lexington, Kentucky, USA, Tel +1 859-218-2237, Email [email protected]: Health-related quality of life (HRQoL) assessments such as St. George’s Respiratory Questionnaire (SGRQ) are often used as outcome measures to evaluate patient-perceived changes in health status among individuals with lung disease. Several factors have been linked to deterioration in SGRQ, including symptoms (dyspnea, wheezing) and exercise intolerance. Whether these findings apply to individuals with alpha-1 antitrypsin deficiency (AATD) remains incompletely studied. This longitudinal study examines the trajectory of SGRQ scores in a cohort of United States individuals with AATD-associated lung disease and defines factors associated with longitudinal change.Methods: Individuals with AATD-associated lung disease enrolled in AlphaNet, a disease management program, who had ≥ 3 SGRQ measurements collected between 2009 and 2019, and baseline data for clinically important variables were included in these analyses. Data collected after lung transplants were excluded. Mixed-effects model analyses were used to evaluate the changes in SGRQ total and subscale scores over time and by modified Medical Research Council (mMRC) Scale, use of oxygen, age, sex, productive cough, and exacerbation frequency at baseline. Sensitivity analyses were conducted to examine the potential effect of survivor bias.Results: Participants (n=2456, mean age 57.1± 9.9 years, 47% female) had a mean SGRQ total score of 44.7± 18.9 at baseline, 48% used oxygen regularly, and 55% had ≥ 2 exacerbations per year. The median length of follow-up was 6 (IQR 3– 9) years. The SGRQ total score and subscales remained stable throughout the observation period. Age, mMRC categories, presence or absence of productive cough, frequency of exacerbations, and use of oxygen at baseline were significantly associated with the rate of change of SGRQ total (p< 0.0001).Conclusion: We observed long-term stability in HRQoL and an association between the rate of change in SGRQ and baseline mMRC, exacerbation frequency, productive cough, and use of oxygen in this cohort of individuals with AATD-associated lung disease.Keywords: COPD, alpha-1 antitrypsin deficiency, quality of lif

Formation of a morphine-conditioned place preference does not change the size of evoked potentials in the ventral hippocampus–nucleus accumbens projection

Abstract In opioid addiction, cues and contexts associated with drug reward can be powerful triggers for drug craving and relapse. The synapses linking ventral hippocampal outputs to medium spiny neurons of the accumbens may be key sites for the formation and storage of associations between place or context and reward, both drug-related and natural. To assess this, we implanted rats with electrodes in the accumbens shell to record synaptic potentials evoked by electrical stimulation of the ventral hippocampus, as well as continuous local-field-potential activity. Rats then underwent morphine-induced (10 mg/kg) conditioned-place-preference training, followed by extinction. Morphine caused an acute increase in the slope and amplitude of accumbens evoked responses, but no long-term changes were evident after conditioning or extinction of the place preference, suggesting that the formation of this type of memory does not lead to a net change in synaptic strength in the ventral hippocampal output to the accumbens. However, analysis of the local field potential revealed a marked sensitization of theta- and high-gamma-frequency activity with repeated morphine administration. This phenomenon may be linked to the behavioral changes—such as psychomotor sensitization and the development of drug craving—that are associated with chronic use of addictive drugs

A genome-wide association meta-analysis of self-reported allergy identifies shared and allergy-specific susceptibility loci

Allergic disease is very common and carries substantial public-health burdens. We conducted a meta-analysis of genome-wide associations with self-reported cat, dust-mite and pollen allergies in 53,862 individuals. We used generalized estimating equations to model shared and allergy-specific genetic effects. We identified 16 shared susceptibility loci with association P < 5 × 10-8, including 8 loci previously associated with asthma, as well as 4p14 near TLR1, TLR6 and TLR10 (rs2101521, P = 5.3 × 10 -21); 6p21.33 near HLA-C and MICA (rs9266772, P = 3.2 × 10 -12); 5p13.1 near PTGER4 (rs7720838, P = 8.2 × 10 -11); 2q33.1 in PLCL1 (rs10497813, P = 6.1 × 10-10), 3q28 in LPP (rs9860547, P = 1.2 × 10-9); 20q13.2 in NFATC2 (rs6021270, P = 6.9 × 10-9), 4q27 in ADAD1 (rs17388568, P = 3.9 × 10-8); and 14q21.1 near FOXA1 and TTC6 (rs1998359, P = 4.8 × 10-8). We identified one locus with substantial evidence of differences in effects across allergies at 6p21.32 in the class II human leukocyte antigen (HLA) region (rs17533090, P = 1.7 × 10-12), which was strongly associated with cat allergy. Our study sheds new light on the shared etiology of immune and autoimmune disease

Emergency pulpotomy in relieving acute dental pain among Tanzanian patients

BACKGROUND: In Tanzania, oral health services are mostly in the form of dental extractions aimed at alleviating acute dental pain. Conservative methods of alleviating acute dental pain are virtually non-existent. Therefore, it was the aim of this study to determine treatment success of emergency pulpotomy in relieving acute dental pain. METHODS: Setting: School of Dentistry, Muhimbili National Hospital, Dar es Salaam, Tanzania. Study design: Longitudinal study. Participants: 180 patients who presented with dental pain due to acute irreversible pulpitis during the study period between July and August 2001. Treatment and evaluation: Patients were treated by emergency pulpotomy on permanent posterior teeth and were evaluated for pain after one, three and six week's post-treatment. Pain, if present, was categorised as either mild or acute. RESULTS: Of the patients with treated premolars, 25 (13.9%) patients did not experience pain at all while 19 (10.6%) experienced mild pain. None of the patients with treated premolars experienced acute pain. Among 136 patients with treated molars 56 (31%) did not experience any pain, 76 (42.2%) experienced mild pain and the other 4 (2.2%) suffered acute pain. CONCLUSION: The short term treatment success of emergency pulpotomy was high being 100% for premolars and 97.1% for molars, suggesting that it can be recommended as a measure to alleviate acute dental pain while other conservative treatment options are being considered

Psychometric performance of the CAMPHOR and SF-36 in pulmonary hypertension

BACKGROUND: The Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) and the Medical Outcomes Study Short Form 36 (SF-36) are widely used to assess patient-reported outcome in individuals with pulmonary hypertension (PH). The aim of the study was to compare the psychometric properties of the two measures. METHODS: Participants were recruited from specialist PH centres in Australia and New Zealand. Participants completed the CAMPHOR and SF-36 at two time points two weeks apart. The SF-36 is a generic health status questionnaire consisting of 36 items split into 8 sections. The CAMPHOR is a PH-specific measure consisting of 3 scales; symptoms, activity limitations and needs-based QoL. The questionnaires were assessed for distributional properties (floor and ceiling effects), internal consistency (Cronbach's alpha), test-retest reliability and construct validity (scores by World Health Organisation functional classification). RESULTS: The sample comprised 65 participants (mean (SD) age = 57.2 (14.5) years; n(%) male = 14 (21.5%)). Most of the patients were in WHO class 2 (27.7%) and 3 (61.5%). High ceiling effects were observed for the SF-36 bodily pain, social functioning and role emotional domains. Test-retest reliability was poor for six of the eight SF-36 domains, indicating high levels of random measurement error. Three of the SF-36 domains did not distinguish between WHO classes. In contrast, all CAMPHOR scales exhibited good distributional properties, test retest reliability and distinguished between WHO functional classes. CONCLUSIONS: The CAMPHOR exhibited superior psychometric properties, compared with the SF-36, in the assessment of PH patient-reported outcome

Isolation and Culture of Larval Cells from C. elegans

Cell culture is an essential tool to study cell function. In C. elegans the ability to isolate and culture cells has been limited to embryonically derived cells. However, cells or blastomeres isolated from mixed stage embryos terminally differentiate within 24 hours of culture, thus precluding post-embryonic stage cell culture. We have developed an efficient and technically simple method for large-scale isolation and primary culture of larval-stage cells. We have optimized the treatment to maximize cell number and minimize cell death for each of the four larval stages. We obtained up to 7.8×104 cells per microliter of packed larvae, and up to 97% of adherent cells isolated by this method were viable for at least 16 hours. Cultured larval cells showed stage-specific increases in both cell size and multinuclearity and expressed lineage- and cell type-specific reporters. The majority (81%) of larval cells isolated by our method were muscle cells that exhibited stage-specific phenotypes. L1 muscle cells developed 1 to 2 wide cytoplasmic processes, while L4 muscle cells developed 4 to 14 processes of various thicknesses. L4 muscle cells developed bands of myosin heavy chain A thick filaments at the cell center and spontaneously contracted ex vivo. Neurons constituted less than 10% of the isolated cells and the majority of neurons developed one or more long, microtubule-rich protrusions that terminated in actin-rich growth cones. In addition to cells such as muscle and neuron that are high abundance in vivo, we were also able to isolate M-lineage cells that constitute less than 0.2% of cells in vivo. Our novel method of cell isolation extends C. elegans cell culture to larval developmental stages, and allows use of the wealth of cell culture tools, such as cell sorting, electrophysiology, co-culture, and high-resolution imaging of subcellular dynamics, in investigation of post-embryonic development and physiology

Supporting adolescent emotional health in schools: a mixed methods study of student and staff views in England

<p>Abstract</p> <p>Background</p> <p>Schools have been identified as an important place in which to support adolescent emotional health, although evidence as to which interventions are effective remains limited. Relatively little is known about student and staff views regarding current school-based emotional health provision and what they would like to see in the future, and this is what this study explored.</p> <p>Methods</p> <p>A random sample of 296 English secondary schools were surveyed to quantify current level of emotional health provision. Qualitative student focus groups (27 groups, 154 students aged 12-14) and staff interviews (12 interviews, 15 individuals) were conducted in eight schools, purposively sampled from the survey respondents to ensure a range of emotional health activity, free school meal eligibility and location. Data were analysed thematically, following a constant comparison approach.</p> <p>Results</p> <p>Emergent themes were grouped into three areas in which participants felt schools did or could intervene: emotional health in the curriculum, support for those in distress, and the physical and psychosocial environment. Little time was spent teaching about emotional health in the curriculum, and most staff and students wanted more. Opportunities to explore emotions in other curriculum subjects were valued. All schools provided some support for students experiencing emotional distress, but the type and quality varied a great deal. Students wanted an increase in school-based help sources that were confidential, available to all and sympathetic, and were concerned that accessing support should not lead to stigma. Finally, staff and students emphasised the need to consider the whole school environment in order to address sources of distress such as bullying and teacher-student relationships, but also to increase activities that enhanced emotional health.</p> <p>Conclusion</p> <p>Staff and students identified several ways in which schools can improve their support of adolescent emotional health, both within and outside the curriculum. However, such changes should be introduced as part of a wider consideration of how the whole school environment can be more supportive of students' emotional health. Clearer guidance at policy level, more rigorous evaluation of current interventions, and greater dissemination of good practice is necessary to ensure adolescents' emotional health needs are addressed effectively within schools.</p