Dopaminergic neuromodulation of prefrontal cortex activity requires the NMDA receptor coagonist d-serine.

Prefrontal control of cognitive functions critically depends upon glutamatergic transmission and N-methyl D-aspartate (NMDA) receptors, the activity of which is regulated by dopamine. Yet whether the NMDA receptor coagonist d-serine is implicated in the dopamine-glutamate dialogue in the prefrontal cortex (PFC) and other brain areas remains unexplored. Here, using electrophysiological recordings, we show that d-serine is required for the fine-tuning of glutamatergic neurotransmission, neuronal excitability, and synaptic plasticity in the PFC through the actions of dopamine at D and D receptors.

D-Serine and Glycine Differentially Control Neurotransmission during Visual Cortex Critical Period.

N-methyl-D-aspartate receptors (NMDARs) play a central role in synaptic plasticity. Their activation requires the binding of both glutamate and d-serine or glycine as co-agonist. The prevalence of either co-agonist on NMDA-receptor function differs between brain regions and remains undetermined in the visual cortex (VC) at the critical period of postnatal development.

Brain-Specific Basal and Novelty-Induced Alternations in PI3K-Akt and MAPK/ERK Signaling in a Middle-Aged AβPP/PS1 Mouse Model of Alzheimer's Disease.

Although it is well established that insulin/IGF and BDNF signaling are dysfunctionally regulated in Alzheimer's disease, there are very few studies documenting changes in major target proteins in different murine models of the disease. We investigated a panel of proteins in the PI3K-Akt and MAPK/ERK cascades in parietal cortex, dentate gyrus and CA1 in 13-month-old AβPP/PS1 transgenic mice to determine whether amyloid pathology is associated with basal dysregulation of these proteins or following exposure to novelty. The most striking effect we found was that there was little common regulation of proteins either by pathology alone or exposure to novelty across the three structures, suggesting dysfunctional mechanisms that occur simultaneously have important structure specificity.

Dysfunctional Dopaminergic Neurones in Mouse Models of Huntington's Disease: A Role for SK3 Channels.

Background: Huntington's disease (HD) is a late-onset fatal neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the gene coding for the protein huntingtin and is characterised by progressive motor, psychiatric and cognitive decline. We previously demonstrated that normal synaptic function in HD could be restored by application of dopamine receptor agonists, suggesting that changes in the release or bioavailability of dopamine may be a contributing factor to the disease process.

Objective: In the present study, we examined the properties of midbrain dopaminergic neurones and dopamine release in presymptomatic and symptomatic transgenic HD mice.

The influence of academic discourses on medical students' identification with the discipline of family medicine.

Purpose: To understand the influence of academic discourses about family medicine on medical students' professional identity construction during undergraduate training.

Method: The authors used a multiple case study research design involving international medical schools, one each from Canada, France, Spain, and the United Kingdom (UK). The authors completed the fieldwork between 2007 and 2009 by conducting 18 focus groups (with 132 students) and 67 semistructured interviews with educators and by gathering pertinent institutional documents.

UV light-induced DNA lesions cause dissociation of yeast RNA polymerases-I and establishment of a specialized chromatin structure at rRNA genes.

The cytotoxicity of UV light-induced DNA lesions results from their interference with transcription and replication. DNA lesions arrest elongating RNA polymerases, an event that triggers transcription-coupled nucleotide excision repair. Since arrested RNA polymerases reduce the accessibility of repair factors to DNA lesions, they might be displaced.

[Study of treatment adherence by patients living with HIV in 2009 at the outpatient care and treatment center of Brazzaville, Congo].

Objectives: The purpose of this study was to evaluate treatment adherence and its determinants in patients living with HIV followed up at the outpatient care and treatment center in Brazzaville, Congo.

Methods: This cross-sectional study included patients who attended the center from July to October 2009. Adherence was evaluated using a self-administered questionnaire, 5 distinct measurement tools, and global adherence index.

Protein 4.1B contributes to the organization of peripheral myelinated axons.

Neurons are characterized by extremely long axons. This exceptional cell shape is likely to depend on multiple factors including interactions between the cytoskeleton and membrane proteins. In many cell types, members of the protein 4.

Evaluation of urinary cotinine immunoassay test strips used to assess smoking status.

Introduction: Validation of smoking status is a vital component for assessing self-reported smoking status. This study examined commercially available urinary cotinine immunoassay strips to evaluate their effectiveness and their reliability in validating self-reported tobacco usage.

Methods: This study compared cotinine values from urinary test strips and liquid chromatography-mass spectrometry (LC-MS/MS) obtained from 100 self-reported nonsmokers and 201 self-reported smokers.

Distinctive features of Egr transcription factor regulation and DNA binding activity in CA1 of the hippocampus in synaptic plasticity and consolidation and reconsolidation of fear memory.

Activity-dependent regulation of Egr1/Zif268, a transcription factor (TF) of the Egr family, is essential for stabilization of dentate gyrus synaptic plasticity and consolidation and reconsolidation of several forms of memory. The gene can be rapidly induced in selective brain circuits after certain types of learning or after recall. Here, we focused on area CA1 and examined regulation of Egr1, Egr2, and Egr3 mRNA and protein, and their DNA binding activity to the Egr response element (ERE) at different times after LTP in vivo and after learning and recall of a fear memory.

The genotoxicity of mainstream and sidestream marijuana and tobacco smoke condensates.

While the prevalence of tobacco use has decreased in Canada over the past decade, that of marijuana use has increased, particularly among youth. However, the risks of adverse health effects from marijuana smoke exposure, specifically as compared to tobacco, are currently not well understood. The objectives of this study were to evaluate the relative ability of matched marijuana and tobacco condensates to induce (geno)toxic responses in three in vitro test systems.

The accuracy of self-reported smoking: a systematic review of the relationship between self-reported and cotinine-assessed smoking status.

Introduction: Smoking is a leading cause of premature mortality and preventable morbidity. Surveillance is most often based on self-reported data, but studies have shown that self-reports tend to underestimate smoking status.

Methods: This study systematically reviewed the literature to measure the concordance between self-reported smoking status and smoking status determined through measures of cotinine in biological fluids.

[Patients members to a network's representations: prospects for the improvement of care].

Objective: Identify the representations of patients regarding their disease, their accession and the positive and resistance factors of their participation in the network to understand how the network could improve their care.

Method: Qualitative survey. We conducted twenty interviews, using open-ended questionnaires, with diabetic type 2 patients, registered for over a year in the healthcare Codiab network in the department of Morbihan.

Structural requirement of TAG-1 for retinal ganglion cell axons and myelin in the mouse optic nerve.

White matter axons organize into fascicles that grow over long distances and traverse very diverse environments. The molecular mechanisms preserving this structure of white matter axonal tracts are not well known. Here, we used the optic nerve as a model and investigated the role of TAG-1, a cell adhesion molecule expressed by retinal axons.

Obstacles to adherence in living with type-2 diabetes: an international qualitative study using meta-ethnography (EUROBSTACLE).

Quantitative studies failed to determine variables which consistently explain adherence or non-adherence to treatment recommendations. Qualitative studies identified issues such as the quality of the health provider-health receiver relationship and the patient's health beliefs. According to these findings, 39 focus groups of 246 people living with type-2 diabetes were conducted in seven European countries, assessing health beliefs, communication with caregivers and problems encountered in adhering to treatment regimens.

A comparison of mainstream and sidestream marijuana and tobacco cigarette smoke produced under two machine smoking conditions.

The chemical composition of tobacco smoke has been extensively examined, and the presence of known and suspected carcinogens in such smoke has contributed to the link between tobacco smoking and adverse health effects. The consumption of marijuana through smoking remains a reality and, among youth, seems to be increasing. There have been only limited examinations of marijuana smoke, including for cannabinoid content and for tar generation.

[Partnership between patients' associations and health professionals: the case of the general practitioner].

Public authorities have opted to promote the representation of patients and health system users within health institutions and regional decision-making bodies. This raises one important question: that of the links and mutual benefits between independent primary providers and users' associations. Patients' associations in the health field are not that well-known among doctors, who are in fact only minutely affected by their activities and hence not very aware of them.

Confidentiality for adolescents seeking reproductive health care in Lithuania: the perceptions of general practitioners.

Confidentiality is a major determinant of the accessibility and acceptability of sexual and reproductive health care for adolescents. Previous research has revealed that Lithuanian adolescents lack confidence in guarantees of confidentiality in primary health care settings. This study aimed to assess the factors that affect general practitioners' decisions whether to respect confidentiality for Lithuanian adolescents under the age of 18.

A high-throughput method to measure the sensitivity of yeast cells to genotoxic agents in liquid cultures.

The sensitivity of yeast Saccharomyces cerevisiae to DNA damaging agents is better represented when cells are grown in liquid media than on solid plates. However, systematic assessment of several strains that are grown in different conditions is a cumbersome undertaking. We report an assay to determine cell growth based on automatic measurements of optical densities of very small (100 microl) liquid cell cultures.

The appropriateness of gatekeeping in the provision of reproductive health care for adolescents in Lithuania:the general practice perspective.

Background: Adolescents' consultation of primary health care services remains problematic despite their accessibility. The reproductive health service seeking behavior of adolescents is the object of much research but little is known about how this behavior is influenced by the gatekeeping system. This study aimed to explore general practitioners' perceptions of the appropriateness of gatekeeping in adolescent reproductive health care.

Psoralen photocrosslinking, a tool to study the chromatin structure of RNA polymerase I--transcribed ribosomal genes.

The chromatin structure of RNA polymerase I--transcribed ribosomal DNA (rDNA) is well characterized. In most organisms, i.e.

[The gynaecological work by GPs in Brittany].

The aim of this study is to evaluate the gynaecological work done by general practitioners (GPs) in Brittany and the clarify the role that they play in screening for female cancers. Gynaecology represents approximately 10% of the total activity reported by the respondents; however, wide variations have also been noted. This raises important questions on issues such as the competence of these practitioners in this area and equity in access to care and screening, which could potential lead to problems.

Anatomical and functional evidence for a role of arginine-vasopressin (AVP) in rat olfactory epithelium cells.

The olfactory epithelium (OE) is composed of olfactory sensory neurons (OSNs) and sustentacular cells; it lies in the nasal cavity where it is protected by a thin mucus layer. The finely regulated composition of this mucus provides OSN with a suitable ionic environment. To maintain the functional integrity of the epithelium despite permanent physical, chemical and microbial aggressions, both OSNs and surrounding sustentacular cells are continuously renewed from globose basal cells.

Engineered yeasts as reporter systems for odorant detection.

The functional expression of olfactory receptors (ORs) is a primary requirement to utilize olfactory detection systems. We have taken advantage of the functional similarities between signal transduction cascades in the budding yeast Saccharomyces cerevisiae and mammalian cells. The yeast pheromone response pathway has been adapted to allow ligand-dependent signaling of heterologous expressed G-protein coupled receptors (GPCRs) via mammalian or chimeric yeast/mammalian Galpha proteins.