290 research outputs found
Harms and benefits associated with psychoactive drugs: findings of an international survey of active drug users.
There have been several recent efforts in the UK and the Netherlands to describe the harms of psychoactive substances based on ratings of either experts or drug users. This study aimed to assess the perceived benefits as well as harms of widely used recreational drugs, both licit and illicit, in an international sample of drug users. The survey was hosted at https://www.internationaldrugsurvey.org/ and was available in three languages. Residents reported their experience of 15 commonly used drugs or drug classes; regular users then rated their harms and benefits. In all, 5791 individuals from over 40 countries completed the survey, although the majority were from English speaking countries. Rankings of drugs differed across 10 categories of perceived benefits. Skunk and herbal cannabis were ranked consistently beneficial, whilst alcohol and tobacco fell below many classified drugs. There was no correlation at all between users' harm ranking of drugs and their classification in schedules of the USA or ABC system in the UK. Prescription analgesics, alcohol and tobacco were ranked within the top 10 most harmful drugs. These findings suggest that neither the UK nor US classification systems act to inform users of the harms of psychoactive substances. It is hoped the results might inform health professionals and educators of what are considered to be both the harms and benefits of psychoactive substances to young people
Mantle-like Sr-Nd isotope composition of Fe-K subalkaline granites : the Peneda-Gerês Variscan massif (NW Iberian Peninsula)
The Peneda-Gerês massif is one of the most representative NW Iberian late- to post-orogenic Variscan granitic plutons. It resulted essentially from the subsynchronous emplacement, at 290-296 Ma, of two granitic magmas of Fe-K subalkaline affinity, with primitive isotopic composition: Sri = 0.703-0.707 and eNdi = -1.5 to -2.4. An origin by mantle input followed by mantle-crust interactions is proposed, implying the contribution of a less enriched mantle component than that involved in the genesis of syn-orogenic hybrid granitoids of Mg-K subalkaline affinity. A less voluminous aluminopotassic and isotopically more evolved magma (Sri = 0.708-0.709 and eNdi = -3.5 to –3.9) with little or no mantle input was also generated, suggesting the involvement of lower crust materials. Therefore, this study suggests an input of juvenile magmas in late-Variscan times, the mantle-like isotope signature of Fe-K granitic magmatism being clearly related to a geodynamic setting of extensional processes, large-scale uplift and thinning
Cryptosporidium Priming Is More Effective than Vaccine for Protection against Cryptosporidiosis in a Murine Protein Malnutrition Model
Cryptosporidium is a major cause of severe diarrhea, especially in malnourished children. Using a murine model of C. parvum oocyst challenge that recapitulates clinical features of severe cryptosporidiosis during malnutrition, we interrogated the effect of protein malnutrition (PM) on primary and secondary responses to C. parvum challenge, and tested the differential ability of mucosal priming strategies to overcome the PM-induced susceptibility. We determined that while PM fundamentally alters systemic and mucosal primary immune responses to Cryptosporidium, priming with C. parvum (106 oocysts) provides robust protective immunity against re-challenge despite ongoing PM. C. parvum priming restores mucosal Th1-type effectors (CD3+CD8+CD103+ T-cells) and cytokines (IFNγ, and IL12p40) that otherwise decrease with ongoing PM. Vaccination strategies with Cryptosporidium antigens expressed in the S. Typhi vector 908htr, however, do not enhance Th1-type responses to C. parvum challenge during PM, even though vaccination strongly boosts immunity in challenged fully nourished hosts. Remote non-specific exposures to the attenuated S. Typhi vector alone or the TLR9 agonist CpG ODN-1668 can partially attenuate C. parvum severity during PM, but neither as effectively as viable C. parvum priming. We conclude that although PM interferes with basal and vaccine-boosted immune responses to C. parvum, sustained reductions in disease severity are possible through mucosal activators of host defenses, and specifically C. parvum priming can elicit impressively robust Th1-type protective immunity despite ongoing protein malnutrition. These findings add insight into potential correlates of Cryptosporidium immunity and future vaccine strategies in malnourished children
Calibration of myocardial T2 and T1 against iron concentration.
BACKGROUND: The assessment of myocardial iron using T2* cardiovascular magnetic resonance (CMR) has been validated and calibrated, and is in clinical use. However, there is very limited data assessing the relaxation parameters T1 and T2 for measurement of human myocardial iron.
METHODS: Twelve hearts were examined from transfusion-dependent patients: 11 with end-stage heart failure, either following death (n=7) or cardiac transplantation (n=4), and 1 heart from a patient who died from a stroke with no cardiac iron loading. Ex-vivo R1 and R2 measurements (R1=1/T1 and R2=1/T2) at 1.5 Tesla were compared with myocardial iron concentration measured using inductively coupled plasma atomic emission spectroscopy.
RESULTS: From a single myocardial slice in formalin which was repeatedly examined, a modest decrease in T2 was observed with time, from mean (± SD) 23.7 ± 0.93 ms at baseline (13 days after death and formalin fixation) to 18.5 ± 1.41 ms at day 566 (p<0.001). Raw T2 values were therefore adjusted to correct for this fall over time. Myocardial R2 was correlated with iron concentration [Fe] (R2 0.566, p<0.001), but the correlation was stronger between LnR2 and Ln[Fe] (R2 0.790, p<0.001). The relation was [Fe] = 5081•(T2)-2.22 between T2 (ms) and myocardial iron (mg/g dry weight). Analysis of T1 proved challenging with a dichotomous distribution of T1, with very short T1 (mean 72.3 ± 25.8 ms) that was independent of iron concentration in all hearts stored in formalin for greater than 12 months. In the remaining hearts stored for <10 weeks prior to scanning, LnR1 and iron concentration were correlated but with marked scatter (R2 0.517, p<0.001). A linear relationship was present between T1 and T2 in the hearts stored for a short period (R2 0.657, p<0.001).
CONCLUSION: Myocardial T2 correlates well with myocardial iron concentration, which raises the possibility that T2 may provide additive information to T2* for patients with myocardial siderosis. However, ex-vivo T1 measurements are less reliable due to the severe chemical effects of formalin on T1 shortening, and therefore T1 calibration may only be practical from in-vivo human studies
Role of Condom Negotiation on Condom use among Women of Reproductive Age in three Districts in Tanzania.
ABSTRACT: BACKGROUND: HIV/AIDS remains being a disease of great public health concern worldwide. In regions such as sub-Saharan Africa (SSA) where women are disproportionately infected with HIV, women are reportedly less likely capable of negotiating condom use. However, while knowledge of condom use for HIV prevention is extensive among men and women in many countries including Tanzania, evidence is limited about the role of condom negotiation on condom use among women in rural Tanzania. METHODS: Data originate from a cross-sectional survey of random households conducted in 2011 in Rufiji, Kilombero and Ulanga districts in Tanzania. The survey assessed health-seeking behaviour among women and children using a structured interviewer-administered questionnaire. A total of 2,614 women who were sexually experienced and aged 15--49 years were extracted from the main database for the current analysis. Linkage between condom negotiation and condom use at the last sexual intercourse was assessed using multivariate logistic regression. RESULTS: Prevalence of condom use at the last sexual intercourse was 22.2% overall, ranging from12.2% among married women to 54.9% among unmarried (single) women. Majority of the women (73.4%) reported being confident to negotiate condom use, and these women were significantly more likely than those who were not confident to have used a condom at the last sexual intercourse (OR = 3.13, 95% CI 2.22-4.41). This effect was controlled for marital status, age, education, religion, number of sexual partners, household wealth and knowledge of HIV prevention by condom use. CONCLUSION: Confidence to negotiate condom use is a significant predictor of actual condom use among women in rural Tanzania. Women especially unmarried ones or those in multiple partnerships should be empowered with condom negotiation skills to enhance their sexual and reproductive health outcomes
Relationship between periodontitis and rheumatoid arthritis and the effect of non-surgical periodontal treatment
Magnetoelectric Effect in Strongly Magnetized Color Superconductivity
The effect of a strong magnetic field on the electric polarization of a
three-flavor color superconducting medium is investigated. We found that the
electric susceptibility of this strongly magnetized medium is highly
anisotropic. In the direction transverse to the applied magnetic field the
susceptibility reduces to that of the vacuum, while in the longitudinal
direction it depends on the magnetic field and decreases with it. The nature of
this behavior is associated with the field's dependence of the Cooper pairs'
coherence length, which plays the role of the electric dipole length. The
field's dependence of the electric polarization is interpreted as the
realization of the magnetoelectric effect in cold-dense quark matter.Comment: 10 pages, 1 figur
A cluster randomized trial of standard quality improvement versus patient-centered interventions to enhance depression care for African Americans in the primary care setting: study protocol NCT00243425
<p>Abstract</p> <p>Background</p> <p>Several studies document disparities in access to care and quality of care for depression for African Americans. Research suggests that patient attitudes and clinician communication behaviors may contribute to these disparities. Evidence links patient-centered care to improvements in mental health outcomes; therefore, quality improvement interventions that enhance this dimension of care are promising strategies to improve treatment and outcomes of depression among African Americans. This paper describes the design of the BRIDGE (Blacks Receiving Interventions for Depression and Gaining Empowerment) Study. The goal of the study is to compare the effectiveness of two interventions for African-American patients with depression--a standard quality improvement program and a patient-centered quality improvement program. The main hypothesis is that patients in the patient-centered group will have a greater reduction in their depression symptoms, higher rates of depression remission, and greater improvements in mental health functioning at six, twelve, and eighteen months than patients in the standard group. The study also examines patient ratings of care and receipt of guideline-concordant treatment for depression.</p> <p>Methods/Design</p> <p>A total of 36 primary care clinicians and 132 of their African-American patients with major depressive disorder were recruited into a cluster randomized trial. The study uses intent-to-treat analyses to compare the effectiveness of standard quality improvement interventions (academic detailing about depression guidelines for clinicians and disease-oriented care management for their patients) and patient-centered quality improvement interventions (communication skills training to enhance participatory decision-making for clinicians and care management focused on explanatory models, socio-cultural barriers, and treatment preferences for their patients) for improving outcomes over 12 months of follow-up.</p> <p>Discussion</p> <p>The BRIDGE Study includes clinicians and African-American patients in under-resourced community-based practices who have not been well-represented in clinical trials to improve depression care. The patient-centered and culturally targeted approach to depression care is a relatively new one that has not been tested in most previous studies. The study will provide evidence about whether patient-centered accommodations improve quality of care and outcomes to a greater extent than standard quality improvement strategies for African Americans with depression.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov NCT00243425</p
Spring-Block Model Reveals Region-Like Structures
A mechanical spring-block model is used for realizing an objective space partition of settlements from a geographic territory in region-like structures. The method is based on the relaxation-dynamics of the spring-block system and reveals in a hierarchical manner region-like entities at different spatial scales. It takes into account in an elegant manner both the spatiality of the elements and the connectivity relations among them. Spatiality is taken into account by using the geographic coordinates of the settlements, and by detecting the neighbors with the help of a Delaunay triangulation. Connectivity between neighboring settlements are quantified using a Pearson-like correlation for the relative variation of a relevant socio-economic parameter (population size, GDP, tax payed per inhabitant, etc.). The method is implemented in an interactive JAVA application and it is applied with success for an artificially generated society and for the case of USA, Hungary and Transylvania
- …