483 research outputs found

    Neurodegeneration progresses despite complete elimination of clinical relapses in a mouse model of multiple sclerosis.

    Get PDF
    BACKGROUND: [corrected] Multiple Sclerosis has two clinical phases reflecting distinct but inter-related pathological processes: focal inflammation drives the relapse-remitting stage and neurodegeneration represents the principal substrate of secondary progression. In contrast to the increasing number of effective anti-inflammatory disease modifying treatments for relapse-remitting disease, the absence of therapies for progressive disease represents a major unmet clinical need. This raises the unanswered question of whether elimination of clinical relapses will prevent subsequent progression and if so how early in the disease course should treatment be initiated. Experimental autoimmune encephalomyelitis in the Biozzi ABH mouse recapitulates the clinical and pathological features of multiple sclerosis including relapse-remitting episodes with inflammatory mediated demyelination and progressive disability with neurodegeneration. To address the relationship between inflammation and neurodegeneration we used an auto-immune tolerance strategy to eliminate clinical relapses in EAE in a manner analogous to the clinical effect of disease modifying treatments. RESULTS: By arresting clinical relapses in EAE at two distinct stages, early and late disease, we demonstrate that halting immune driven demyelination even after the first major clinical event is insufficient to prevent long-term neurodegeneration and associated gliosis. Nonetheless, early intervention is partially neuroprotective, whereas later interventions are not. Furthermore early tolerisation is also associated with increased remyelination. CONCLUSIONS: These findings are consistent with both a partial uncoupling of inflammation and neurodegeneration and that the regenerative response of remyelination is negatively correlated with inflammation. These findings strongly support the need for early combinatorial treatment of immunomodulatory therapies and neuroprotective treatments to prevent long-term neurodegeneration in multiple sclerosis

    Pheromone Binding to General Odorant-binding Proteins from the Navel Orangeworm

    Get PDF
    General odorant-binding proteins (GOBPs) of moths are postulated to be involved in the reception of semiochemicals other than sex pheromones, the so-called “general odorants.” We have expressed two GOBPs, AtraGOBP1 and AtraGOBP2, which were previously isolated from the antennae of the navel orangeworm, Amyelois transitella. Surprisingly, these two proteins did not bind compounds that are known to attract adult moths, particularly females. The proper folding and functionality of the recombinant proteins was inferred from circular dichroism analysis and demonstration that both GOBPs bound nonanal in a pH-dependent manner. EAG experiments demonstrated that female attractants (1-phenylethanol, propionic acid phenyl ester, and isobutyric acid phenyl ester) are detected with high sensitivity by the antennae of day-0 to day-4 adult females, with response declining in older moths. The same age-dependence was shown for male antennae responding to constituents of the sex pheromone. Interestingly, AtraGOBP2 bound the major constituent of the sex pheromone, Z11Z13-16Ald, with affinity comparable to that shown by a pheromone-binding protein, AtraPBP1. The related alcohol bound to AtraPBP1 with higher affinity than to AtraGOBP2. AtraGOBP1 bound both ligands with low but nearly the same affinity

    Asteroseismology

    Full text link
    Asteroseismology is the determination of the interior structures of stars by using their oscillations as seismic waves. Simple explanations of the astrophysical background and some basic theoretical considerations needed in this rapidly evolving field are followed by introductions to the most important concepts and methods on the basis of example. Previous and potential applications of asteroseismology are reviewed and future trends are attempted to be foreseen.Comment: 38 pages, 13 figures, to appear in: "Planets, Stars and Stellar Systems", eds. T. D. Oswalt et al., Springer Verla

    Acute aortic dissection type A discloses Corpus alienum

    Get PDF
    We report an unusual case of an aortic type A dissection with a corpus alienum which compresses the right ventricle. The patient successfully underwent an aortic root replacement in deep hypothermia with re-implantation of the coronary arteries using a modified Bentall procedure and the resection of the corpus alienum. Intraoperative finding reveals 3 greatly adhered gauze compresses, which were most likely forgotten in the operation 34 years ago

    Risk Factors for Posttraumatic Stress Disorder Among Deployed US Male Marines

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Combat exposure has been reported as one of the strongest risk factors for postdeployment posttraumatic stress disorder (PTSD) among military service members. Determining the impact of specific deployment-related exposures on the risk of developing PTSD has not been fully explored. Our study objective was to explore the relationship between specific combat exposures and other life experiences with postdeployment PTSD.</p> <p>Methods</p> <p>This study consisted of male Marines who completed a Recruit Assessment Program (RAP) survey during recruit training at the Marine Corps Recruit Depot in San Diego, California as well as a follow-up survey several years after recruit training. Study participants included those Marines who deployed to the current operations in Iraq or Afghanistan between the baseline and follow-up surveys. Multivariable logistic regression was performed to determine which significant exposures and experiences were associated with postdeployment PTSD.</p> <p>Results</p> <p>Of the 706 study participants, 10.8% screened positive for postdeployment PTSD. Those who reported feeling in great danger of death (odds ratio [OR] = 4.63, 95% confidence interval [CI]: 2.46-8.73), were shot or seriously injured (OR = 3.51, 95% CI: 1.58-7.77), saw someone wounded or killed (OR = 2.47, 95% CI: 1.08-5.67), and baseline (before recruit training) prior violence exposures (OR = 2.99, 95% CI: 1.46-6.10) were at increased odds for reporting PTSD symptoms. Number of deployments, number of close friends or relatives reported at follow-up, and enlisted pay grade were also significantly associated with postdeployment PTSD.</p> <p>Conclusions</p> <p>Combat exposures, specifically the threat of death, serious injury, and witnessing injury or death are significant risk factors for screening positive for postdeployment PTSD among male Marines as well as violence exposures prior to entering the Marine Corps, which are independent of future combat exposures. A thorough history of lifetime violence exposures should be pursued when considering a clinical diagnosis of PTSD.</p

    Evaluating the Relationship between Spermatogenic Silencing of the X Chromosome and Evolution of the Y Chromosome in Chimpanzee and Human

    Get PDF
    Chimpanzees and humans are genetically very similar, with the striking exception of their Y chromosomes, which have diverged tremendously. The male-specific region (MSY), representing the greater part of the Y chromosome, is inherited from father to son in a clonal fashion, with natural selection acting on the MSY as a unit. Positive selection might involve the performance of the MSY in spermatogenesis. Chimpanzees have a highly polygamous mating behavior, so that sperm competition is thought to provide a strong selective force acting on the Y chromosome in the chimpanzee lineage. In consequence of evolution of the heterologous sex chromosomes in mammals, meiotic sex chromosome inactivation (MSCI) results in a transcriptionally silenced XY body in male meiotic prophase, and subsequently also in postmeiotic repression of the sex chromosomes in haploid spermatids. This has evolved to a situation where MSCI has become a prerequisite for spermatogenesis. Here, by analysis of microarray testicular expression data representing a small number of male chimpanzees and men, we obtained information indicating that meiotic and postmeiotic X chromosome silencing might be more effective in chimpanzee than in human spermatogenesis. From this, we suggest that the remarkable reorganization of the chimpanzee Y chromosome, compared to the human Y chromosome, might have an impact on its meiotic interactions with the X chromosome and thereby on X chromosome silencing in spermatogenesis. Further studies will be required to address comparative functional aspects of MSCI in chimpanzee, human, and other placental mammals

    Treating tobacco dependence in older adults: a survey of primary care clinicians’ knowledge, attitudes, and practice

    Get PDF
    BACKGROUND: The benefits of smoking cessation among older people are well documented. Despite this, evidence suggests that older smokers are rarely engaged in smoking cessation efforts, and that existing tobacco dependence treatments require further tailoring to the specific needs of older smokers. This study assesses the knowledge, attitudes, and clinical practice of primary care clinicians in relation to addressing tobacco dependence among older people. METHODS: A cross-sectional survey of 427 NHS primary care clinicians in a large English city was conducted using modified version of a previously validated questionnaire. RESULTS: One hundred and seventy one clinicians (40 % response rate) completed the survey. While the majority (90.0 %) of respondents reported enquiring regularly about older patients’ smoking status, just over half (59.1 %) reported providing older patients with smoking cessation support. A lack of awareness in relation to the prevalence and impact of smoking in later life were apparent: e.g. only 47 % of respondents were aware of that approximately 10 life years are lost due to smoking related disease, and only 59 % knew that smoking can reduce the effectiveness of medication prescribed for conditions common in later life. Self-reported attendance at smoking-related training was significantly associated with proactive clinical practice. CONCLUSIONS: There is a need to improve clinicians’ knowledge, in relation to smoking and smoking cessation in older patients and to build clinician confidence in seizing teachable moments. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12875-015-0317-7) contains supplementary material, which is available to authorized users

    Loss of Pluripotency in Human Embryonic Stem Cells Directly Correlates with an Increase in Nuclear Zinc

    Get PDF
    The pluripotency of human embryonic stem cells (hESCs) is important to investigations of early development and to cell replacement therapy, but the mechanism behind pluripotency is incompletely understood. Zinc has been shown to play a key role in differentiation of non-pluripotent cell types, but here its role in hESCs is directly examined. By mapping the distribution of metals in hESCs at high resolution by x-ray fluorescence microprobe (XFM) and by analyzing subcellular metal content, we have found evidence that loss of pluripotency is directly correlated with an increase in nuclear zinc. Zinc elevation not only redefines our understanding of the mechanisms that support pluripotency, but also may act as a biomarker and an intervention point for stem cell differentiation

    The Transcriptome of Lutzomyia longipalpis (Diptera: Psychodidae) Male Reproductive Organs

    Get PDF
    BACKGROUND: It has been suggested that genes involved in the reproductive biology of insect disease vectors are potential targets for future alternative methods of control. Little is known about the molecular biology of reproduction in phlebotomine sand flies and there is no information available concerning genes that are expressed in male reproductive organs of Lutzomyia longipalpis, the main vector of American visceral leishmaniasis and a species complex. METHODS/PRINCIPAL FINDINGS: We generated 2678 high quality ESTs ("Expressed Sequence Tags") of L. longipalpis male reproductive organs that were grouped in 1391 non-redundant sequences (1136 singlets and 255 clusters). BLAST analysis revealed that only 57% of these sequences share similarity with a L. longipalpis female EST database. Although no more than 36% of the non-redundant sequences showed similarity to protein sequences deposited in databases, more than half of them presented the best-match hits with mosquito genes. Gene ontology analysis identified subsets of genes involved in biological processes such as protein biosynthesis and DNA replication, which are probably associated with spermatogenesis. A number of non-redundant sequences were also identified as putative male reproductive gland proteins (mRGPs), also known as male accessory gland protein genes (Acps). CONCLUSIONS: The transcriptome analysis of L. longipalpis male reproductive organs is one step further in the study of the molecular basis of the reproductive biology of this important species complex. It has allowed the identification of genes potentially involved in spermatogenesis as well as putative mRGPs sequences, which have been studied in many insect species because of their effects on female post-mating behavior and physiology and their potential role in sexual selection and speciation. These data open a number of new avenues for further research in the molecular and evolutionary reproductive biology of sand flies

    The association between active participation in a sports club, physical activity and social network on the development of lung cancer in smokers: a case-control study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>This study analyses the effect of active participation in a sports club, physical activity and social networks on the development of lung cancer in patients who smoke. Our hypothesis is that study participants who lack social networks and do not actively participate in a sports club are at a greater risk for lung cancer than those who do.</p> <p>Methods</p> <p>Data for the study were taken from the <b>Co</b>logne <b>Smo</b>king <b>S</b>tudy (<b>CoSmoS</b>), a retrospective case-control study examining potential psychosocial risk factors for the development of lung cancer. Our sample consisted of n = 158 participants who had suffered lung cancer (diagnosis in the patient document) and n = 144 control group participants. Both groups had a history of smoking.</p> <p>Data on social networks were collected by asking participants whether they participated in a sports club and about the number of friends and relatives in their social environment. In addition, sociodemographic data (gender, age, education, marital status, residence and religion), physical activity and data on pack years (the cumulative number of cigarettes smoked by an individual, calculated by multiplying the number of cigarettes smoked per day by the number of years the person has smoked divided by 20) were collected to control for potential confounders. Logistic regression was used for the statistical analysis.</p> <p>Results</p> <p>The results reveal that participants who are physically active are at a lower risk of lung cancer than those who are not (adjusted OR = 0.53*; CI = 0.29-0.97). Older age and lower education seem also to be risk factors for the development of lung cancer. The extent of smoking, furthermore, measured by pack years is statistically significant. Active participation in a sports club, number of friends and relatives had no statistically significant influence on the development of the cancer.</p> <p>Conclusions</p> <p>The results of the study suggest that there is a lower risk for physically active participants to develop lung cancer. In the study sample, physical activity seemed to have a greater protective effect than participation in a sports club or social network of friends and relatives. Further studies have to investigate in more detail physical activity and other club participations.</p
    corecore