402 research outputs found
The dual-function glutamate transporters: structure and molecular characterisation of the substrate-binding sites
AbstractGlutamate transporters are essential for terminating synaptic excitation and for maintaining extracellular glutamate concentrations below neurotoxic levels. These transporters also mediate a thermodynamically uncoupled chloride flux, activated by two of the molecules they transport, sodium and glutamate. Five eukaryotic glutamate transporters have been cloned and identified. They exhibit ∼50% identity and this homology is even greater at the carboxyl terminal half, which is predicted to have an unusual topology. Determination of the topology shows that the carboxyl terminal part contains several transmembrane domains separated by two reentrant loops that are in close proximity to each other. We have identified several conserved amino acid residues in the carboxyl terminal half that play crucial roles in the interaction of the transporter with its substrates: sodium, potassium and glutamate. The conformation of the transporter gating the anion conductance is different from that during substrate translocation. However, there exists a dynamic equilibrium between these conformations
Parental strain, mental health problems, and parenting practices: A longitudinal study
Although poor parenting practices place youth living in under resourced communities at heightened risk for adjustment difficulties, less is known about what influences parenting practices in those communities. The present study examines prospective linkages between three latent constructs: parental strain, mental health problems and parenting practices. Parental victimization by community violence and life stressors were indicative of parental strain; depressive, anxious, and hostile symptoms were indicators of parental mental health; and parental knowledge of their child’s activities and child disclosure were indicators of parenting practices. Interviews were conducted annually for 3 waves with 316 female caregivers (92% African American) parenting youth in low-income inner-city communities. Structural equation modeling revealed that parental strain, assessed at Wave 1, predicted changes in mental health problems one year later, which in turn predicted parenting practices at Wave 3. These results suggest that parental strain can compromise a caregiver’s ability to parent effectively by impacting their mental health. Opportunities for intervention include helping caregivers process trauma and mental health problems associated with parental strain
Object identification and characterization with hyperspectral imagery to identify structure and function of Natura 2000 habitats
Habitat monitoring of designated areas under the EU Habitats Directive requires every 6 years information on area, range, structure and function for the protected (Annex I) habitat types. First results from studies on heathland areas in Belgium and the Netherlands show that hyperspectral imagery can be an important source of information to assist the evaluation of the habitat conservation status. Hyperspectral imagery can provide continuous maps of habitat quality indicators (e.g., life forms or structure types, management activities, grass, shrub and tree encroachment) at the pixel level. At the same time, terrain managers, nature conservation agencies and national authorities responsible for the reporting to the EU are not directly interested in pixels, but rather in information at the level of vegetation patches, groups of patches or the protected site as a whole. Such local level information is needed for management purposes, e.g., exact location of patches of habitat types and the sizes and quality of these patches within a protected site. Site complexity determines not only the classification success of remote sensing imagery, but influences also the results of aggregation of information from the pixel to the site level. For all these reasons, it is important to identify and characterize the vegetation patches. This paper focuses on the use of segmentation techniques to identify relevant vegetation patches in combination with spectral mixture analysis of hyperspectral imagery from the Airborne Hyperspectral Scanner (AHS). Comparison with traditional vegetation maps shows that the habitat or vegetation patches can be identified by segmentation of hyperspectral imagery. This paper shows that spectral mixture analysis in combination with segmentation techniques on hyperspectral imagery can provide useful information on processes such as grass encroachment that determine the conservation status of Natura 2000 heathland areas to a large extent. A limitation is that both advanced remote sensing approaches and traditional field based vegetation surveys seem to cause over and underestimations of grass encroachment for specific categories, but the first provides a better basis for monitoring if specific species are not directly considered
An object-based approach to quantity and quality assessment of heathland habitats in the framework of natura 2000 using hyperspectral airborne ahs images
Use of prescription drugs and future delinquency among adolescent offenders
Non-medical use of prescription drugs (NMUPD) by adolescents is a significant public health concern. The present study investigated the profile of NMUPD in 1349 adolescent offenders from the Pathways to Desistance project, and whether NMUPD predicted future delinquency using longitudinal data. Results indicated that increased frequency and recency of NMUPD in adolescent offenders are related to some demographic factors, as well as increased risk for violence exposure, mental health diagnoses, other drug use, and previous delinquency, suggesting that severity of NMUPD is important to consider. However, ANCOVA analyses found that NMUPD was not a significant predictor of drug-related, non-aggressive, or aggressive delinquency 12 months later beyond other known correlates of delinquency. Age, sex, exposure to violence, lower socioeconomic status, more alcohol use, and having delinquency histories were more important than NMUPD in predicting future delinquency. These findings suggest that although NMUPD is an important risk factor relating to many correlates of delinquency, it does not predict future delinquency beyond other known risk factors
User requirements towards the use of remote sensing for Natura 2000 habitat monitoring: a need for formalization
Phase III Trial of PROSTVAC in Asymptomatic or Minimally Symptomatic Metastatic Castration-Resistant Prostate Cancer
Cà ncer de pròstata; Metà stasi neoplà sica; Immunoterà piaCáncer de próstata; Metástasis neoplásica; InmunoterapiaProstate cancer; Metastatic neoplasm; ImmunotherapyPURPOSE PROSTVAC, a viral vector–based immunotherapy, prolonged median overall survival (OS) by 8.5 months versus placebo in metastatic castration-resistant prostate cancer in a phase II study. This phase III study further investigated those findings.
PATIENTS AND METHODS Patients were randomly assigned to PROSTVAC (Arm V; n = 432), PROSTVAC plus granulocyte-macrophage colony-stimulating factor (Arm VG; n = 432), or placebo (Arm P; n = 433), stratified by prostate-specific antigen (less than 50 ng/mL v 50 ng/mL or more) and lactate dehydrogenase (less than 200 v 200 U/L or more). Primary end point was OS. Secondary end points were patients alive without events
(AWE)—namely, radiographic progression, pain progression, chemotherapy initiation, or death—at 6 months and safety. The study design was a superiority trial of PROSTVAC (Arm V or Arm VG) versus Arm P. Three interim analyses were planned.
RESULTS At the third interim analysis, criteria for futility were met and the trial was stopped early. Neither active treatment had an effect on median OS (Arm V, 34.4 months; hazard ratio, 1.01; 95% CI, 0.84 to 1.20; P = .47; Arm VG, 33.2 months; hazard ratio, 1.02; 95% CI, 0.86 to 1.22; P = .59; Arm P, 34.3 months). Likewise, AWE at 6 months was similar (Arm V, 29.4%; odds ratio, 0.96; 95% CI, 0.71 to 1.29; Arm VG, 28.0%; odds ratio, 0.89;
95% CI, 0.66 to 1.20; placebo, 30.3%). Adverse events were similar for the treatment and placebo groups, with the most common being injection site reactions (62% to 72%) and fatigue (21% to 24%). Arrhythmias were the most common cardiac-related events (1.4% to 3.5%). There were no reports of either myocarditis or pericarditis. Serious treatment-related events occurred in less than 1% of all patients.
CONCLUSION Whereas PROSTVAC was safe and well tolerated, it had no effect on OS or AWE in metastatic castration-resistant prostate cancer. Combination therapy is currently being explored in clinical trials.Supported by Bavarian Nordic, the National Institute for Health Research Biomedical Research Centre at the Royal Marsden National Health Service Foundation Trust, and the Institute of Cancer Research. Funded in part by National Cancer Institute Cancer Center Support Grant No. P30-CA008748 and the Center for Cancer Research, National Cancer Institute.P30 CA008748/CA/NCI NIH HHS/United States DH_/Department of Health/United Kingdo
Risk factors and incidence of long-COVID syndrome in hospitalized patients: does remdesivir have a protective effect?
BACKGROUND: The definition of 'long-COVID syndrome' (LCS) is still debated and describes the persistence of symptoms after viral clearance in hospitalized or non-hospitalized patients affected by coronavirus disease 2019 (COVID-19). AIM: In this study, we examined the prevalence and the risk factors of LCS in a cohort of patients with previous COVID-19 and followed for at least 6 months of follow-up. DESIGN: We conducted a prospective study including all hospitalized patients affected by COVID-19 at our center of Infectious Diseases (Vercelli, Italy) admitted between 10 March 2020 and 15 January 2021 for at least 6 months after discharge. Two follow-up visits were performed: after 1 and 6 months after hospital discharge. Clinical, laboratory and radiological data were recorded at each visit. RESULTS: A total of 449 patients were included in the analysis. The LCS was diagnosed in 322 subjects at Visit 1 (71.7%) and in 206 at Visit 2 (45.9); according to the post-COVID-19 functional status scale we observed 147 patients with values 2-3 and 175 with values >3 at Visit 1; at Visit 2, 133 subjects had the score between 2-3 and 73 > 3. In multivariate analysis, intensive care unit (ICU) admission (OR = 2.551; 95% CI = 1.998-6.819; P = 0.019), time of hospitalization (OR = 2.255; 95% CI = 1.018-6.992; P = 0.016) and treatment with remdesivir (OR = 0.641; 95% CI = 0.413-0.782; P < 0.001) were independent predictors of LCS. CONCLUSIONS: Treatment with remdesivir leads to a 35.9% reduction in LCS rate in follow-up. Severity of illness, need of ICU admission and length of hospital stay were factor associated with the persistence of PCS at 6 months of follow-up
- …