Genome-wide screen of genes required for caffeine tolerance in fission yeast

Background: An excess of caffeine is cytotoxic to all eukaryotic cell types. We aim to study how cells become tolerant to atoxic dose of this drug, and the relationship between caffeine and oxidative stress pathways.Methodology/Principal Findings: We searched for Schizosaccharomyces pombe mutants with inhibited growth on caffeinecontainingplates. We screened a collection of 2,700 haploid mutant cells, of which 98 were sensitive to caffeine. The genes mutated in these sensitive clones were involved in a number of cellular roles including the H2O2-induced Pap1 and Sty1 stress pathways, the integrity and calcineurin pathways, cell morphology and chromatin remodeling. We have investigated the role of the oxidative stress pathways in sensing and promoting survival to caffeine. The Pap1 and the Sty1 pathways are both required for normal tolerance to caffeine, but only the Sty1 pathway is activated by the drug. Cells lacking Pap1 aresensitive to caffeine due to the decreased expression of the efflux pump Hba2. Indeed, ?hba2 cells are sensitive to caffeine, and constitutive activation of the Pap1 pathway enhances resistance to caffeine in an Hba2-dependent manner. Conclusions/Significance: With our caffeine-sensitive, genome-wide screen of an S. pombe deletion collection, we havedemonstrated the importance of some oxidative stress pathway components on wild-type tolerance to the drug.

Profiles of drug users in Switzerland and effects of early-onset intensive use of alcohol, tobacco and cannabis on other illicit drug use.

QUESTIONS UNDER STUDY / PRINCIPLES: The main aim of this study was to investigate profiles of drug users, with a particular focus on illicit drugs other than cannabis, and to explore the effect of early-onset intensive use (drunkenness, daily smoking, high on cannabis) on profiles of illicit drug use. METHODS: Baseline data from a representative sample of 5,831 young Swiss men in the ongoing Cohort Study on Substance Use Risk Factors were used. Substance use (alcohol, tobacco, cannabis and 15 types of other illicit drug) and age of onset of intensive use were assessed. The Item Response Theory (IRT) and prevalence rates at different ages of onset were used to reveal different profiles of illicit drug use. RESULTS: In addition to cannabis, there were two profiles of other illicit drug use: (a) "softer" drug users (uppers, hallucinogens and inhaled drugs), among which ecstasy had the highest discriminatory potential (IRT slope = 4.68, standard error (SE) = 0.48; p <0.001); and (b) "harder" drug users (heroin, ketamine, gamma-hydroxybutyrate/gamma-hydroxylactone, research chemicals, crystal meth and spice), among which ketamine had the highest discriminatory potential (slope = 4.05; SE = 0.63; p <0.001). Onset of intensive use at the age of 12 years or younger also discriminated between these two profiles. CONCLUSION: Both the IRT model and the effect of onset of intensive use enabled two groups of illicit drugs to be identified. In particular, very early onset (at 12 years or younger) intensive use of any substance was a marker for later use of the second group of drugs.

Voluntary alcohol consumption is controlled via the neuropeptide Y Y1 receptor.

We have shown previously that voluntary ethanol consumption and resistance to ethanol-induced sedation are inversely related to neuropeptide Y (NPY) levels in NPY-knock-out (NPY(-/-)) and NPY-overexpressing mice. In the present report, we studied knock-out mice completely lacking the NPY Y1 receptor (Y1(-/-)) to further characterize the role of the NPY system in ethanol consumption and neurobiological responses to this drug. Here we report that male Y1(-/-) mice showed increased consumption of solutions containing 3, 6, and 10% (v/v) ethanol when compared with wild-type (Y1(+/+)) control mice. Female Y1(-/-) mice showed increased consumption of a 10% ethanol solution. In contrast, Y1(-/-) mice showed normal consumption of solutions containing either sucrose or quinine. Relative to Y1(+/+) mice, male Y1(-/-) mice were found to be less sensitive to the sedative effects of 3.5 and 4.0 gm/kg ethanol as measured by more rapid recovery from ethanol-induced sleep, although plasma ethanol levels did not differ significantly between the genotypes. Finally, male Y1(-/-) mice showed normal ethanol-induced ataxia on the rotarod test after administration of a 2.5 gm/kg dose. These data suggest that the NPY Y1 receptor regulates voluntary ethanol consumption and some of the intoxicating effects caused by administration of ethanol.

Tumor endothelium FasL establishes a selective immune barrier promoting tolerance in tumors.

We describe a new mechanism regulating the tumor endothelial barrier and T cell infiltration into tumors. We detected selective expression of the death mediator Fas ligand (FasL, also called CD95L) in the vasculature of human and mouse solid tumors but not in normal vasculature. In these tumors, FasL expression was associated with scarce CD8(+) infiltration and a predominance of FoxP3(+) T regulatory (Treg) cells. Tumor-derived vascular endothelial growth factor A (VEGF-A), interleukin 10 (IL-10) and prostaglandin E2 (PGE2) cooperatively induced FasL expression in endothelial cells, which acquired the ability to kill effector CD8(+) T cells but not Treg cells because of higher levels of c-FLIP expression in Treg cells. In mice, genetic or pharmacologic suppression of FasL produced a substantial increase in the influx of tumor-rejecting CD8(+) over FoxP3(+) T cells. Pharmacologic inhibition of VEGF and PGE2 produced a marked increase in the influx of tumor-rejecting CD8(+) over FoxP3(+) T cells that was dependent on attenuation of FasL expression and led to CD8-dependent tumor growth suppression. Thus, tumor paracrine mechanisms establish a tumor endothelial death barrier, which has a critical role in establishing immune tolerance and determining the fate of tumors.

Pivotal role for a tail subunit of the RNA polymerase II mediator complex CgMed2 in azole tolerance and adherence in Candida glabrata.

Antifungal therapy failure can be associated with increased resistance to the employed antifungal agents. Candida glabrata, the second most common cause of invasive candidiasis, is intrinsically less susceptible to the azole class of antifungals and accounts for 15% of all Candida bloodstream infections. Here, we show that C. glabrata MED2 (CgMED2), which codes for a tail subunit of the RNA polymerase II Mediator complex, is required for resistance to azole antifungal drugs in C. glabrata. An inability to transcriptionally activate genes encoding a zinc finger transcriptional factor, CgPdr1, and multidrug efflux pump, CgCdr1, primarily contributes to the elevated susceptibility of the Cgmed2Δ mutant toward azole antifungals. We also report for the first time that the Cgmed2Δ mutant exhibits sensitivity to caspofungin, a constitutively activated protein kinase C-mediated cell wall integrity pathway, and elevated adherence to epithelial cells. The increased adherence of the Cgmed2Δ mutant was attributed to the elevated expression of the EPA1 and EPA7 genes. Further, our data demonstrate that CgMED2 is required for intracellular proliferation in human macrophages and modulates survival in a murine model of disseminated candidiasis. Lastly, we show an essential requirement for CgMed2, along with the Mediator middle subunit CgNut1 and the Mediator cyclin-dependent kinase/cyclin subunit CgSrb8, for the high-level fluconazole resistance conferred by the hyperactive allele of CgPdr1. Together, our findings underscore a pivotal role for CgMed2 in basal tolerance and acquired resistance to azole antifungals.

Actitud ante el consumo y no consumo de alcohol en estudiantes de preparatoria – México

El objetivo del estudio fue identificar diferencias de actitud entre estudiantes de la educación secundaria consumidores y no de alcohol a través de la Teoría de la Conducta Planeada. Estudio descriptivo transversal con abordaje cuantitativo, con una muestra de 131 adolescentes. Se verifi có que 74% ya habían consumido alcohol y 18.3% tienen consumo dañino. Se constató que las creencias conductuales hacia el consumo eran más altas en los consumidores de alcohol (X=29.32, Mdn=27.50) que en los no consumidores, así con la evaluación de las creencias en sentido positivo son más altas en los consumidores de alcohol (X=17.72, Mdn=9.52) que en los no consumidores, haciéndose necesaria la implementación de programas preventivos que fortalezcan las creencias de los adolescentes, así como estimular las estrategias vinculadas con el fortalecimiento de factores protectores y estilos de vida saludables.

Importance of genotypic and phenotypic tolerance in the treatment of experimental endocarditis due to Streptococcus gordonii.

Genotypic and phenotypic tolerance was studied in penicillin treatment of experimental endocarditis due to nontolerant and tolerant Streptococcus gordonii and to their backcross transformants. The organisms were matched for in vitro and in vivo growth rates. Rats with aortic endocarditis were treated for 3 or 5 days, starting 12, 24, or 48 h after inoculation. When started at 12 h, during fast intravegetation growth, 3 days of treatment cured 80% of the nontolerant parent compared with &lt;30% of the tolerant derivative (P &lt; .005). When started at 24 or 48 h and if intravegetation growth had reached a plateau, 3 days of treatment failed against both bacteria. However, a significant difference between the 2 organisms was restored when treatment was extended to 5 days. Thus, genotypic tolerance conferred a survival advantage in both fast- and slow-growing bacteria, demonstrating that the in vitro-defined tolerant phenotype also carried the risk of treatment failure in vivo.

Knowledge and attitudes of nurses towards alcohol and related problems: the impact of an educational intervention

An exploratory study of quasi-experimental approach that aimed to verify the impact of an educational intervention on attitudes and knowledge of nurses towards alcohol use and associated problems. The sample included 185 nurses, divided into two groups: 84 submitted to a training course and formed the experimental group. Data were collected through a knowledge survey and an attitude scale. The attitudes of the participants of both groups were positive. There were no significant differences between groups in relation to knowledge. The strongest predictors of positive attitudes were possessed preparation to act with chemical dependents (OR = 2.18), "have received increased workload during graduation on the theme, 'alcohol and other drugs'" (OR = 1.70), and "completed graduate school" (OR = 2.59). The educational intervention had a positive impact on the attitudes of nurses towards alcoholics, work and interpersonal relationships with such clientele.

Error and attack tolerance of layered complex networks.

Many complex systems may be described by not one but a number of complex networks mapped on each other in a multi-layer structure. Because of the interactions and dependencies between these layers, the state of a single layer does not necessarily reflect well the state of the entire system. In this paper we study the robustness of five examples of two-layer complex systems: three real-life data sets in the fields of communication (the Internet), transportation (the European railway system), and biology (the human brain), and two models based on random graphs. In order to cover the whole range of features specific to these systems, we focus on two extreme policies of system's response to failures, no rerouting and full rerouting. Our main finding is that multi-layer systems are much more vulnerable to errors and intentional attacks than they appear from a single layer perspective.

Estoy sola: la experiencia de las enfermeras en el cuidado del usuario de alcohol y drogas

El propósito de este estudio es comprender cómo es ser enfermera vivenciando el cuidado de pacientes drogodependientes que ingresan al Servicio de Medicina de un hospital público de Chile. Se opta por un estudio de tipo cualitativo, de trayectoria fenomenológica, según el referencial de Martín Heidegger. La pregunta orientadora fue: ¿Cómo es cuidar a pacientes drogodependientes que ingresan en tu servicio? Los discursos de las enfermeras fueron interpretados bajo el referencial de Fenómeno Situado de Joel Martins. Después del análisis de las entrevistas, se identificó 3 temas que expresan el fenómeno: hablando del paciente drogodependiente, cuidando al paciente en un medio adverso, superando el miedo para cuidar. El estudio muestra la necesidad de capacitar al personal de salud en dependencia en alcohol y drogas para superar los preconceptos y mejorar el cuidado de estos pacientes.

Social use of alcohol among adolescent offenders: a fundamental approach toward human needs

This study examined some basic health care approaches toward human needs, with a particular focus on nursing. We aimed to incorporate these approaches into the discussion of the mental health of adolescent offenders who consume alcohol. We discuss specific needs of the delinquent group, critique policies that prioritize coercion of adolescent offenders, and the role that nurses could play in the sphere of juvenile delinquency.

Patterns of alcohol use and related issues: analysis of nurses' knowledge


Descriptive study that aimed to identify and compare the nurses’ knowledge addressed to patterns of alcohol use and related issues. The study included 185 nurses of which 84 had attended a training course on the subject. Data were collected through a questionnaire of knowledge showing that while the trained group obtained the highest average on correct answers, there was a lack of knowledge in both groups, especially with regard to the identification of complications from alcohol use. Important definitions to nursing practice in the area of addictions are presented, suggesting that future training may consider the various dimensions involved in caring for people with problems related to alcohol.


Prevalence of alcohol-impaired drivers based on random breath tests in a roadside survey

Sobriety checkpoints are not usually randomly located by traffic authorities. As such, information provided by non-random alcohol tests cannot be used to infer the characteristics of the general driving population. In this paper a case study is presented in which the prevalence of alcohol-impaired driving is estimated for the general population of drivers. A stratified probabilistic sample was designed to represent vehicles circulating in non-urban areas of Catalonia (Spain), a region characterized by its complex transportation network and dense traffic around the metropolis of Barcelona. Random breath alcohol concentration tests were performed during spring 2012 on 7,596 drivers. The estimated prevalence of alcohol-impaired drivers was 1.29%, which is roughly a third of the rate obtained in non-random tests. Higher rates were found on weekends (1.90% on Saturdays, 4.29% on Sundays) and especially at night. The rate is higher for men (1.45%) than for women (0.64%) and the percentage of positive outcomes shows an increasing pattern with age. In vehicles with two occupants, the proportion of alcohol-impaired drivers is estimated at 2.62%, but when the driver was alone the rate drops to 0.84%, which might reflect the socialization of drinking habits. The results are compared with outcomes in previous surveys, showing a decreasing trend in the prevalence of alcohol-impaired drivers over time.