Host carbon sources modulate cell wall architecture, drug resistance and virulence in a fungal pathogen

The survival of all microbes depends upon their ability to respond to environmental challenges. To establish infection, pathogens such as Candida albicans must mount effective stress responses to counter host defences while adapting to dynamic changes in nutrient status within host niches. Studies of C. albicans stress adaptation have generally been performed on glucose-grown cells, leaving the effects of alternative carbon sources upon stress resistance largely unexplored. We have shown that growth on alternative carbon sources, such as lactate, strongly influence the resistance of C. albicans to antifungal drugs, osmotic and cell wall stresses. Similar trends were observed in clinical isolates and other pathogenic Candida species. The increased stress resistance of C. albicans was not dependent on key stress (Hog1) and cell integrity (Mkc1) signalling pathways. Instead, increased stress resistance was promoted by major changes in the architecture and biophysical properties of the cell wall. Glucose- and lactate-grown cells displayed significant differences in cell wall mass, ultrastructure, elasticity and adhesion. Changes in carbon source also altered the virulence of C. albicans in models of systemic candidiasis and vaginitis, confirming the importance of alternative carbon sources within host niches during C. albicans infection

Differences between children and adolescents in treatment response to atomoxetine and the correlation between health-related quality of life and Attention Deficit/Hyperactivity Disorder core symptoms: Meta-analysis of five atomoxetine trials

<p>Abstract</p> <p>Objectives</p> <p>To explore the influence of age on treatment responses to atomoxetine and to assess the relationship between core symptoms of attention deficit/hyperactivity disorder (ADHD) and health-related quality of life (HR-QoL) outcomes.</p> <p>Data Sources</p> <p>Data from five similar clinical trials of atomoxetine in the treatment of children and adolescents with ADHD were included in this meta-analysis.</p> <p>Study Selection</p> <p>Atomoxetine studies that used the ADHD Rating Scale (ADHD-RS) and the Child Health and Illness Profile Child Edition (CHIP-CE) as outcome measures were selected.</p> <p>Interventions</p> <p>Treatment with atomoxetine.</p> <p>Main Outcome Measures</p> <p>Treatment group differences (atomoxetine vs placebo) in terms of total score, domains, and subdomains of the CHIP-CE were compared across age groups, and correlations between ADHD-RS scores and CHIP-CE scores were calculated by age.</p> <p>Results</p> <p>Data of 794 subjects (611 children, 183 adolescents) were pooled. At baseline, adolescents showed significantly (p < 0.05) greater impairment compared with children in the Family Involvement, Satisfaction with Self, and Academic Performance subdomains of the CHIP-CE. Treatment effect of atomoxetine was significant in both age groups for the Risk Avoidance domain and its subdomains. There was a significant age-treatment interaction with greater efficacy seen in adolescents in both the Risk Avoidance domain and the Threats to Achievement subdomain. Correlations between ADHD-RS and CHIP-CE scores were generally low at baseline and moderate in change from baseline and were overall similar in adolescents and children.</p> <p>Conclusions</p> <p>Atomoxetine was effective in improving some aspects of HR-QoL in both age groups. Correlations between core symptoms of ADHD and HR-QoL were low to moderate.</p

Atomoxetine treatment and ADHD-related difficulties as assessed by adolescent patients, their parents and physicians

<p>Abstract</p> <p>Background</p> <p>The degree of ADHD-related difficulties – reflecting overall impairment, social functioning, and quality of life – may be perceived differently by adolescent patients, parents and physicians. The primary aim of this study was to investigate ADHD-related difficulties during atomoxetine treatment, as perceived by the three different raters. Secondary objectives focused on effectiveness and tolerability of atomoxetine treatment in a population of adolescent patients with ADHD.</p> <p>Methods</p> <p>Adolescents with ADHD, aged 12–17 years, received open-label atomoxetine (0.5–1.2 mg/kg/day) up to 24 weeks. ADHD-related difficulties at various times of the day were rated using the Global Impression of Perceived Difficulties (GIPD) instrument. Inter-rater agreement was analyzed using Cohen's Kappa with 95% confidence intervals (95% CI). ADHD-Rating Scale (ADHD-RS) and Clinical Global Impression Severity (GGI-S) scores were assessed by the investigator; and spontaneous adverse events, vital signs and laboratory parameters were collected for tolerability assessments.</p> <p>Results</p> <p>159 patients received atomoxetine. Patients' baseline mean GIPD total ratings were significantly lower than parents' and physicians' scores (12.5 [95%CI 11.6;13.5] vs. 17.2 [16.2;18.2] and 18.8 [17.8;19.8]). For all raters, GIPD scores significantly improved over time. Changes were greatest within the first two weeks. Kappa coefficients varied between 0.186 [0.112;0.259] and 0.662 [0.529;0.795], with strongest agreements between parent and physician assessments, and significant improvements of patient/physician agreements over time (based on 95% CIs). ADHD-RS and CGI-S scores significantly improved over the course of the study (based on 95% CIs). Tolerability results were consistent with earlier reports.</p> <p>Conclusion</p> <p>ADHD-related difficulties were perceived differently by the raters in this open-label trial, but consistently improved during atomoxetine treatment. The GIPD instrument appeared sensitive to treatment-related change. These primarily quantitative findings may guide future studies to more systematically investigate the clinical and practical relevance of the differences observed. Additionally, in order to further validate these results, placebo- and comparator-controlled trials are recommended as well as inclusion of healthy controls and other patient populations.</p> <p>Trial Registration</p> <p><b>Clinical Trial Registry</b>: ClinicalTrials.gov: NCT00191737</p

Characterizing Exoplanets in the Visible and Infrared: A Spectrometer Concept for the EChO Space Mission

Transit-spectroscopy of exoplanets is one of the key observational techniques to characterize the extrasolar planet and its atmosphere. The observational challenges of these measurements require dedicated instrumentation and only the space environment allows an undisturbed access to earth-like atmospheric features such as water or carbon-dioxide. Therefore, several exoplanet-specific space missions are currently being studied. One of them is EChO, the Exoplanet Characterization Observatory, which is part of ESA's Cosmic Vision 2015-2025 program, and which is one of four candidates for the M3 launch slot in 2024. In this paper we present the results of our assessment study of the EChO spectrometer, the only science instrument onboard this spacecraft. The instrument is a multi-channel all-reflective dispersive spectrometer, covering the wavelength range from 400 nm to 16 microns simultaneously with a moderately low spectral resolution. We illustrate how the key technical challenge of the EChO mission - the high photometric stability - influences the choice of spectrometer concept and drives fundamentally the instrument design. First performance evaluations underline the fitness of the elaborated design solution for the needs of the EChO mission.Comment: 20 pages, 8 figures, accepted for publication in the Journal of Astronomical Instrumentatio

Change in the direct cost of treatment for children and adolescents with hyperkinetic disorder in Germany over a period of four years

Abstract Background In many developed countries, the treatment of hyperkinetic disorder (or ADHD) consumes a considerable amount of resources. The primary aim of this study was to determine change in the direct cost of treatment for children and adolescents with hyperkinetic disorder in Germany over time, and compare the cost with the cost of treatment for two physical disorders: epilepsy and asthma. Methods The German Federal Statistical Office provided data on the direct cost of treating hyperkinetic disorder, epilepsy and asthma in Germany for 2002, 2004, and 2006. The direct costs of treatment incurred by hyperkinetic disorder in these years were compared with those incurred by epilepsy and asthma. Results The total direct cost of treatment for the hyperkinetic disorder was € 177 million in 2002, € 234 million in 2004, and € 341 million in 2006. The largest proportion of the cost was incurred by the age group Conclusion The direct cost of treatment for hyperkinetic disorder in the age group < 15 years increased considerably between 2002 and 2006. Over the same period of time and for the same age group, expenditure for epilepsy and asthma was more or less constant. The increase in expenditure for the treatment of hyperkinetic disorder may be due to increasing demand for diagnostic and therapeutic services and improved availability of such services. The study is limited by the difficulty of obtaining consistent data on the direct cost of treatment for both physical and psychiatric disorders in Germany.</p

Does switching from oral extended-release methylphenidate to the methylphenidate transdermal system affect health-related quality-of-life and medication satisfaction for children with attention-deficit/hyperactivity disorder?

Background: To evaluate health-related quality of life (HRQL) and medication satisfaction after switching from a stable dose of oral extended-release methylphenidate (ER-MPH) to methylphenidate transdermal system (MTS) via a dose-transition schedule in children with attention-deficit/hyperactivity disorder (ADHD). Methods: In a 4-week, multisite, open-label study, 171 children (164 in the intent-to-treat [ITT] population) aged 6-12 years diagnosed with ADHD abruptly switched from a stable dose of oral ER-MPH to MTS nominal dosages of 10, 15, 20, and 30 mg using a predefined dose-transition schedule. Subjects remained on the scheduled dose for the first week, after which the dose was then titrated to an optimal effect. The ADHD Impact Module-Children (AIM-C), a disease-specific validated HRQL survey instrument measuring child and family impact, was used to assess the impact of ADHD symptoms on the lives of children and their families at baseline and study endpoint. Satisfaction with MTS use was assessed via a Medication Satisfaction Survey (MSS) at study endpoint. Both the AIM-C and MSS were completed by a caregiver (parent/legally authorized representative). Tolerability was monitored by spontaneous adverse event (AE) reporting. Results: AIM-C child and family HRQL mean scores were above the median possible score at baseline and were further improved at endpoint across all MTS doses. Similar improvements were noted for behavior, missed doses, worry, and economic impact AIM-C item scores. Overall, 93.8% of caregivers indicated a high level of satisfaction with their child's use of the study medication. The majority of treatment-emergent AEs (> 98%) were mild to moderate in intensity, and the most commonly reported AEs included headache, decreased appetite, insomnia, and abdominal pain. Seven subjects discontinued the study due to intolerable AEs (n = 3) and application site reactions (n = 4). Conclusion: This study demonstrates that MTS, when carefully titrated to optimal dose, may further improve child and family HRQL, as well as behavioral, medication worry, and economic impact item scores, as measured by the AIM-C in subjects switching to MTS from a stable dose of routinely prescribed oral ER-MPH after a short treatment period. Furthermore, following the abrupt conversion from oral ER-MPH to MTS, the majority of caregivers reported being highly satisfied with MTS as a treatment option for their children with ADHD. Trial Registration: NCT0015198

Partial complementation of Sinorhizobium meliloti bacA mutant phenotypes by the Mycobacterium tuberculosis BacA protein

The Sinorhizobium meliloti BacA ABC transporter protein plays an important role in its nodulating symbiosis with the legume alfalfa (Medicago sativa). The Mycobacterium tuberculosis BacA homolog was found to be important for the maintenance of chronic murine infections, yet its in vivo function is unknown. In the legume plant as well as in the mammalian host, bacteria encounter host antimicrobial peptides (AMPs). We found that the M. tuberculosis BacA protein was able to partially complement the symbiotic defect of an S. meliloti BacA-deficient mutant on alfalfa plants and to protect this mutant in vitro from the antimicrobial activity of a synthetic legume peptide, NCR247, and a recombinant human \u3b2-defensin 2 (HBD2). This finding was also confirmed using an M. tuberculosis insertion mutant. Furthermore, M. tuberculosis BacA-mediated protection of the legume symbiont S. meliloti against legume defensins as well as HBD2 is dependent on its attached ATPase domain. In addition, we show that M. tuberculosis BacA mediates peptide uptake of the truncated bovine AMP, Bac71-16. This process required a functional ATPase domain. We therefore suggest that M. tuberculosis BacA is important for the transport of peptides across the cytoplasmic membrane and is part of a complete ABC transporter. Hence, BacA-mediated protection against host AMPs might be important for the maintenance of latent infections