Dextran sulfate enhances the level of an oxidative DNA damage biomarker, 8-oxo-7,8-dihydro-2 0-deoxyguanosine, in rat colonic mucosa

Dextran sodium sulfate (DSS) given in drinking water can induce colonic Inflammation and produce colorectal tumors in rodents, although it is not directly genotoxic. The hypothesis that DSS can produce free radicals and induce oxidative DNA damage in colonic mucosa has been tested. In rats fed for 2 days with water containing 3% and 6% DSS, colonic Inflammation manifestations were recorded and 8-oxo-7,8-dihydro-2 0-deoxyguanosine (8-oxodGuo), a major biomarker of oxidative DNA damage, was assayed in colonic mucosa. As compared with control rats given pure water, inflammatory manifestations were seen in rats given DSS. At the same time, 8-oxodGuo levels in colonic mucosa were doubled (P , 0:001). These results suggest that formation of oxidative DNA damage in colonic mucosa depends on inflammation and maybe on the production of reactive oxygen species. This study shows that DSS can induce oxidative DNA damage within only 2 days, which could explain in part its carcinogenic properties

Making students sensitive to entrepreneurship

The aim of this paper is to present a {proposal to make students sensitive to entrepreneurship} aiming at familiarizing students to the setting up of new firms and stimulating such a course of action. This {{awareness campaign}} would take place during the student's curriculum and rest on a simulation exercise. This campaign is based on the results of a survey conducted at the Technical University of Cartagena (Spain). This study has identified some students’ aspirations to salaried employment and entrepreneurship. This survey also recognized some specific features that the campaign must integrate, in particular the need to make entrepreneurship compatible with the preparation for salaried employment. The results of this study are completed comparing them with the opinion from entrepreneurs of the same region. This comparison highlights some barriers to entrepreneurship among the students population, making it possible to complete the content of the proposed simulation exercise. This paper also highlights the absence of barriers of a psychological nature usually put forward by the literature, such as a low level of the {need for achievement or the propensity for risk-taking}.career, company, entrepreneurship, making sensitive, student

The primacy of cognition in the manifestations of substance use disorders

Fil: Bisagno, Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas (i); ArgentinaFil: Cadet, Jean Lud. National Institute On Drug Abuse; Estados Unido

Early Middle Paleozoic Intraplate Orogeny in the Ogcheon Belt (South Korea): A new insight on the Paleozoic buildup of east Asia

Laurent Jolivet est Professeur à l'Université d'Orléans depuis le 1er septembre 2009.International audienceThe polycyclic Ogcheon belt of South Korea represents the boundary between two Precambrian blocks. Investigation on the timing and kinematics of the block agglomeration is of considerable bearing on the understanding of the constitution of the Asian continent. We report here structural evidence showing that the earlier tectonic event dates back to early middle Paleozoic (the "Ogcheon tectonism" or "orogeny"). The ductile piling up of nappes of the Ogcheon belt corresponds to an intracontinental orogeny involving the opening and the subsequent closure of an aborted rift and not of a wide oceanic area. The nappes contain unequivocal evidence for ductile shearing with a northwest over southeast sense of movement. Field evidence includes the presence of S1 and S1-2 foliations bearing an extensive stretching lineation perpendicular to the belt, associated with a strongly noncoaxial deformation regime. The F1 isoclinal folds are commonly "A type" and sheath folds whose axes are parallel to the stretching lineation, whereas the southeast facing F2 recumbent folds have subhorizontal axes parallel to the belt. All lines of evidence (unconformity, superposed deformations, age of the metamorphism, etc...) imply that the D1-2 "Ogcheon tectonism" is pre-middle Carboniferous (Late Silurian-Early Devonian). The subsequent Indosinian (Middle Triassic) F3 upright synfolial folds that trend NNE-SSW and later structures clearly overprint the middle Paleozoic ductile thrusts and isoclinal folds. The early Paleozoic Ogcheon Supergroup is formed of a thick volcanosedimentary pile deposited above an early platform sequence in a rift basin. On the basis of the geochemical characteristics of the metavolcanics, it appears that oceanization did not occur and Ogcheon rift aborted soon after it was formed. We suggest that middle Paleozoic ductile nappe structures have been formed by the structural inversion of the rift extensional features. During the ductile stacking episode, the early formed foliation and isoclinal folds have been folded in a continuum during the same tectonic event. Middle Carboniferous terrigenous formations have been deposited unconformably upon folded and thrust older rocks. A tentative correlation with early Paleozoic Imjingang, Qinling and Cathaysian belts within the Asian continent reveals that Ogcheon rift was emplaced within the South China plate and that Imjingang belt should represent the limit between North and South China blocks in the Korean peninsula

Glial-neuronal ensembles: partners in drug addiction-associated synaptic plasticity

Drug addiction is manifested by a compulsive drive to take licit or illicit substances despite repeated severe adverse consequences (Volkow et al., 2012). Addiction is also accompanied by a vicious cycle of binges, abstinence, and relapses. Almost all drugs of abuse trigger euphoric feelings consequent to a rapid increase of dopamine levels in the mesolimbic system. Even after long periods of abstinence, addicts remain vulnerable to drug craving and/or relapses that can be triggered by stimuli previously associated with drugs (Koob and Volkow, 2010). These features of addiction suggest that drugs might cause a form of persistent neuroplasticity that is acutely responsive to environmental stimuli, with consequent compulsive drug-seeking and taking behaviors.Fil: Cadet, Jean Lud. National Institute on Drug Abuse; Estados UnidosFil: Bisagno, Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas (i); Argentina. Universidad de Buenos Aires; Argentin

La politique commerciale des États-Unis et le régionalisme dans les Amériques

Le continentalisme et le panaméricanisme inspiré de la doctrine Monroe ont toujours été des données fondamentales de la politique étrangère des États-Unis et l’Amérique latine a toujours été perçue comme faisant partie de leur sphère d’influence naturelle. Si les questions économiques n’ont jamais été secondaires, la priorité a cependant toujours été accordée aux questions de sécurité dans les rapports avec le reste du continent.Introduction; 1. La politique commerciale américaine: continuité et particularités; 2. De la redéfinition des intérêts économiques et des questions de sécurité au régionalisme ouvert; 3. Du régionalisme ouvert aux alliances commerciales; Conclusion

DRD2 and DRD4 genes related to cognitive deficits in HIV‑infected adults who abuse alcohol

Background HIV-infected individuals continue to experience neurocognitive deterioration despite virologically successful treatments. The causes of neurocognitive impairment are still unclear. However, several factors have been suggested including the role of genetics. There is evidence suggesting that neurocognitive impairment is heritable and individual differences in cognition are strongly driven by genetic variations. The contribution of genetic variants affecting the metabolism and activity of dopamine may influence these individual differences. Methods The present study explored the relationship between two candidate genes (DRD4 and DRD2) and neurocognitive performance in HIV-infected adults. A total of 267 HIV-infected adults were genotyped for polymorphisms, DRD4 48 bp-variable number tandem repeat (VNTR), DRD2 rs6277 and ANKK1 rs1800497. The Short Category (SCT), Color Trail (CTT) and Rey-Osterrieth Complex Figure Tests (ROCT) were used to measure executive function and memory. Results Results showed significant associations with the SNP rs6277 and impaired executive function (odds ratio = 3.3, 95 % CI 1.2–2.6; p = 0.004) and cognitive flexibility (odds ratio = 1.6, 95 % CI 2.0–5.7; p = 0.001). The results were further stratified by race and sex and significant results were seen in males (odds ratio = 3.5, 95 % CI 1.5–5.5; p = 0.008) and in African Americans (odds ratio = 3.1, 95 % CI 2.3–3.5; p = 0.01). Also, DRD4 VNTR 7-allele was significantly associated with executive dysfunction. Conclusion The study shows that genetically determined differences in the SNP rs6277 DRD2 gene and DRD4 48 bp VNTR may be risk factors for deficits in executive function and cognitive flexibility

Unusually Large Deuterium Discrimination during Spore Photoproduct Formation

The deuterium-labeling strategy has been widely used and proved highly effective in mechanistic investigation of chemical and biochemical reactions. However, it is often hampered by the incomplete label transfer, which subsequently obscures the mechanistic conclusion. During the study of photoinduced generation of 5-thyminyl-5,6-dihydrothymine, which is commonly called the spore photoproduct (SP), the Cadet laboratory found an incomplete (∼67%) deuterium transfer in SP formation, which contrasts to the exclusive transfer observed by the Li laboratory. Here, we investigated this discrepancy by re-examining the SP formation using d3-thymidine. We spiked the d3-thymidine with varying amounts of unlabeled thymidine before the SP photochemistry is performed. Strikingly, our data show that the reaction is highly sensitive to the trace protiated thymidine in the starting material. As many as 17-fold enrichment is detected in the formed SP, which may explain the previously observed one-third protium incorporation. Although commercially available deuterated reagents are generally satisfactory as mechanistic probes, our results argue that attention is still needed to the possible interference from the trace protiated impurity, especially when the reaction yield is low and large isotopic discrimination is involved

Serotonin-Related Gene Polymorphisms and Asymptomatic Neurocognitive Impairment in HIV-Infected Alcohol Abusers

HIV-infected individuals continue to experience neurocognitive deterioration despite virologically successful treatments. While the cause remains unclear, evidence suggests that HIV-associated neurocognitive disorders (HAND) may be associated with neurobehavioral dysfunction. Genetic variants have been explored to identify risk markers to determine neuropathogenesis of neurocognitive deterioration. Memory deficits and executive dysfunction are highly prevalent among HIV-infected adults. These conditions can affect their quality of life and HIV risk-taking behaviors. Single nucleotide polymorphisms in the SLC6A4, TPH2, and GALM genes may affect the activity of serotonin and increase the risk of HAND. The present study explored the relationship between SLC6A4, TPH2, and GALM genes and neurocognitive impairment in HIV-infected alcohol abusers. A total of 267 individuals were genotyped for polymorphisms in SLC6A4 5-HTTLPR, TPH2 rs4570625, and GALM rs6741892. To assess neurocognitive functions, the Short Category and the Auditory Verbal Learning Tests were used. TPH2 SNP rs4570625 showed a significant association with executive function in African American males (odds ratio 4.8, 95% CI, 1.5–14.8; ). Similarly, GALM SNP rs6741892 showed an increased risk with African American males (odds ratio 2.4, 95% CI, 1.2–4.9; ). This study suggests that TPH2 rs4570625 and GALM rs6741892 polymorphisms may be risk factors for HAND