Assembly of an adult type acetylcholine receptor in a mouse cell line transfected with rat muscle epsilon-subunit DNA.

AbstractThe mouse muscle cell line BC3H-1 expresses an acetylcholine receptor (AChR) composed of α-,β-, and δ-subunits [1]. The functional characteristics of this AChR are comparable to the non-synaptic AChR subtype in mouse muscle [2,3]. To investigate the role of the ϵ-subunit, which is believed to replace the γ-subunit in forming the adult AChR subtype [4], BC3H-1 cells were stably transfected with cDNA encoding the rat muscle AChR ϵ-subunit. Expression of this cDNA was under the control of a heat shock promoter, and the plasmid carried the neomycin resistance gene for selection. Several clones were isolated that had integrated the plasmid DNA in a stable form and produced ϵ-subunit specific RNA after heat induction. Single-channel current recording from cells which contained abundant ϵ-subunit mRNA identified a novel AChR channel having a larger conductance than the native AChR in these cells. These results suggest that the rat muscle ϵ-subunit may assemble with mouse muscle α-, β- and δ-subunits to form a mouse-rat hybrid AChR with properties similar to that of end-plate channels in the mature mammalian neuromuscular synapse. The novel AChR channel appears in the surface membrane within a few hours following the rise in ϵ-subunit mRNA. Thus, the notion that replacement of the γ-subunit by the ϵ-subunit during development is the result of the postnatal rise in the level of ϵ-subunit specific mRNA is further supported

Determination of the Thermal Resistance of Pipe Insulation Material from Thermal Conductivity of Flat Insulation Products

New European product standards now include a mandatory requirement for manufacturers to declare the temperature-dependent thermal conductivity for each insulation used in building equipments and industrial installations. For pipe insulation systems, the measurement is usually performed by a standard pipe test method, in which the value on a large temperature range is integrated to reduce temperature range and improve temperature measurement control. The alternative proposed in this article consists in determining the thermal conductivity of a pipe insulation system from the results measured on a flat slab specimen. The protocol used in this study consists in collecting the thermal conductivity data and then in fitting the curve with a polynomial regression, using a leastsquare method. The comparison between the pipe insulation specimen and the flat slab product is then done at a specified temperature using the extrapoled polynomial. The methodology is illustrated with a mineral wool over a large range of temperature

Area of comfort: Russian language training for Vietnamese students at technical university

The paper focuses on the psychological and pedagogical peculiarities of teaching Russian to students from Vietnam. The methodology approach taken in this study is motivated by ideas of active Learning articulated by Verbitcky and the Motivation theory developed by Maslow and Yakimanskaya. The methodological basis of the research is a student-centered learning approach. The author provides a theoretical framework based on the communicative competence concept elaborated by Viatiutnev in area of theory and methods Russian as foreign language. Our qualitative methodology included interviews with students, review of documents and analysis of educational results. The authors use Smekal and Kucher’s Questionnaire to identify psychological characteristics of Vietnamese students and offer a solution to the problem of effective teaching with due consideration of the students’ cultural features. The authors present the research findings on the personality orientation of Vietnamese students enrolled in National Research Tomsk Polytechnic University. In general, we systematize suggestions for Russian Language teachers who work with international students from Vietnam

An in-depth look into PTSD-depression comorbidity: A longitudinal study of chronically-exposed Detroit residents

Background Although PTSD-major depressive disorder (MDD) co-morbidity is well-established, the vast majority of studies have examined comorbidity at the level of PTSD total severity, rather than at the level of specific PTSD symptom clusters. This study aimed to examine the long-term associations between MDD and PTSD symptom clusters (intrusion, avoidance, hyperarousal), and the moderating role of gender in these associations. Methods 942 residents of urban Detroit neighborhoods were interviewed at 3 waves, 1 year apart. At each wave, they were assessed for PTSD, depression, trauma exposure, and stressful life events. Results At all waves, hyperarousal was the PTSD cluster most strongly correlated with MDD. For the full sample, a reciprocal relationship was found between MDD and all three PTSD clusters across time. Interestingly, the relative strength of associations between MDD and specific PTSD clusters changed over time. Women showed the same bidirectional MDD-PTSD pattern as in the entire sample, while men sometimes showed non-significant associations between early MDD and subsequent PTSD clusters. Limitations First, our analyses are based on DSM-IV criteria, as this was the existing edition at the time of this study. Second, although this is a longitudinal study, inferences regarding temporal precedence of one disorder over another must be made with caution. Conclusions Early identification of either PTSD or MDD following trauma may be crucial in order to prevent the development of the other disorder over time. The PTSD cluster of hyper-arousal may require special therapeutic attention. Also, professionals are encouraged to develop more gender-specific interventions post-trauma

Epigenetic modifications associated with suicide and common mood and anxiety disorders: a systematic review of the literature

Epigenetic modifications are those reversible, mitotically heritable alterations in genomic expression that occur independent of changes in gene sequence. Epigenetic studies have the potential to improve our understanding of the etiology of mood and anxiety disorders and suicide by bridging the gap in knowledge between the exogenous environmental exposures and pathophysiology that produce common mood and anxiety disorders and suicide. We systematically reviewed the English-language peer-reviewed literature about epigenetic regulation in these disorders between 2001–2011, summarizing and synthesizing this literature with respect to directions for future work. Twenty-one articles met our inclusion criteria. Twelve studies were concerned with epigenetic changes among suicide completers; other studies considered epigenetic regulation in depression, post-traumatic stress disorder, and panic disorder. Several studies focused on epigenetic regulation of amine, glucocorticoid, and serotonin metabolism in the production of common mood and anxiety disorders and suicide. The literature is nascent and has yet to reach consensus about the roles of particular epigenetic modifications in the etiology of these outcomes. Future studies require larger sample sizes and measurements of environmental exposures antecedent to epigenetic modification. Further work is also needed to clarify the link between epigenetic modifications in the brain and peripheral tissues and to establish ‘gold standard’ epigenetic assays

Risk Factors for Course of Posttraumatic Stress Disorder Among Vietnam Veterans: A 14-Year Follow-Up of American Legionnaires

Risk factors affecting the course of posttraumatic stress disorder (PTSD) are poorly understood. As part of a larger study on characterizing exposure to herbicides in Vietnam, the authors investigated this issue in a random sample of 1,377 American Legionnaires who had served in Southeast Asia during the Vietnam War and were followed over a 14-year period. High combat exposure, perceived negative community attitudes at homecoming, minority race, depression symptoms at Time 1, and more anger at Time 1 predicted a more chronic course. Community involvement at Time 1 was protective and associated with decreased risk at Time 2. Discomfort in disclosing Vietnam experiences was associated with an increased risk for developing PTSD but did not predict its course. Combat exposure predicted PTSD course more strongly than any other risk factor. Findings suggest recovery from PTSD is significantly influenced by perceived social support

Persisting Posttraumatic Stress Disorder Symptoms and their Relationship to Functioning in Vietnam Veterans: A 14-Year Follow-Up

The authors examined the longitudinal association between persisting posttraumatic stress disorder (PTSD) symptoms and multiple domains of life functioning in a community sample of 1,377 American Legionnaire Vietnam veterans first assessed in 1984 and followed-up 14 years later. Almost 30 years after their return from Vietnam, 10% of veterans continued to experience severe PTSD symptoms. At all levels of combat exposure, persisting severe PTSD symptoms were associated with worse family relationships, more smoking, less life satisfaction and happiness, more mental health service use, and more nonspecific health complaints at the 14-year follow-up. Further investigation is needed to determine whether the PTSD-functioning relationship is causal and if successful treatment of PTSD is associated with improvement in functioning