38 research outputs found

    Distinctive subdomains in the resorbing surface of osteoclasts.

    Get PDF
    We employed a novel technique to inspect the substrate-apposed surface of activated osteoclasts, the cells that resorb bone, in the scanning electron microscope. The surface revealed unexpected complexity. At the periphery of the cells were circles and crescents of individual or confluent nodules. These corresponded to the podosomes and actin rings that form a 'sealing zone', encircling the resorptive hemivacuole into which protons and enzymes are secreted. Inside these rings and crescents the osteoclast surface was covered with strips and patches of membrane folds, which were flattened against the substrate surface and surrounded by fold-free membrane in which many orifices could be seen. Corresponding regions of folded and fold-free membrane were found by transmission electron microscopy in osteoclasts incubated on bone. We correlated these patterns with the distribution of several proteins crucial to resorption. The strips and patches of membrane folds corresponded in distribution to vacuolar H+-ATPase, and frequently co-localized with F-actin. Cathepsin K localized to F-actin-free foci towards the center of cells with circular actin rings, and at the retreating pole of cells with actin crescents. The chloride/proton antiporter ClC-7 formed a sharply-defined band immediately inside the actin ring, peripheral to vacuolar H+-ATPase. The sealing zone of osteoclasts is permeable to molecules with molecular mass up to 10,000. Therefore, ClC-7 might be distributed at the periphery of the resorptive hemivacuole in order to prevent protons from escaping laterally from the hemivacuole into the sealing zone, where they would dissolve the bone mineral. Since the activation of resorption is attributable to recognition of the Ī±VĪ²3 ligands bound to bone mineral, such leakage would, by dissolving bone mineral, release the ligands and so terminate resorption. Therefore, ClC-7 might serve not only to provide the counter-ions that enable proton pumping, but also to facilitate resorption by acting as a 'functional sealing zone'

    Effectiveness of Education of Self-esteem Behavior-Cognition Approach on High School Male Studentsā€™ Aggression in Shahre-Kurd

    No full text
    This study was conducted in order to examine effectiveness of educating self-esteem behavior-cognition approach on studentsā€™ aggression. The methodology was experimental research with pre-test and post-test for control group. Statistical population included all high school male stu-dents in Share-Kurd. The sample was 30 students whom were selected among 100 students answering aggression questionnaire, their scores were one standard deviation lower than mean and these 30 students were randomly categorized in two 15-person experimental and control groups. Experimental group attended in 8 sessions of self-esteem behavior-cognition education, 1.5 hour per week while control group did not receive any educational courses. Research tools included Coopersmith self-esteem questionnaire, Buss and Perri aggression questionnaire and after data collection, covariance analysis was used in addition to descriptive statistics methods for data analysis. Data analysis shows that self-esteem behavior-cognition education in (P<0/05) causes reduction of teensā€™ aggression.

    Rupture of aortic aneurysm with right-sided haemothorax

    No full text

    Challenging neuroscience and evolutionary explanations of social and psychological processes

    Get PDF
    In order to provide the context for this special issue of Contemporary Social Science, a brief reviewof the biological and evolutionary explanations of psychological and socio-cultural phenomena is presented. This distinguishes five separate aspects of whatmay be characterised as ā€˜biologisingā€™ the social sciences: Darwinian theories, neuroscience explanations, genetic causation, pharmacological and hormonal causes, and the less fundamentalist use of evolutionary ideas as analogies or metaphors. The remarkable range of phenomena that these biologically oriented perspectives try to address is cause for some scepticism and concern, forming the basis for an overview of the growing groundswell of arguments that challenge attempts at biologising the social sciences. At the heart of these challenges is the recognition that human beings can talk and interact with each other, generating cultures and societies that have an existence that cannot be reduced to their mere mechanical parts

    Slow Dynamics of Acute Postoperative Pain Intensity Time Series Determined via Wavelet Analysis Are Associated with the Risk of Severe Postoperative Day 30 Pain

    No full text
    BACKGROUND: Evidence suggests that increased early postoperative pain (POP) intensities are associated with increased pain in the weeks following surgery. However, it remains unclear which temporal aspects of this early POP relate to later pain experience. In this prospective cohort study, we used wavelet analysis of clinically captured POP intensity data on postoperative days 1 and 2 to characterize slow/fast dynamics of POP intensities and predict pain outcomes on postoperative day 30. METHODS: The study used clinical POP time series from the first 48 hours following surgery from 218 patients to predict their mean POP on postoperative day 30. We first used wavelet analysis to approximate the POP series and to represent the series at different time scales to characterize the early temporal profile of acute POP in the first 2 postoperative days. We then used the wavelet coefficients alongside demographic parameters as inputs to a neural network to predict the risk of severe pain 30 days after surgery. RESULTS: Slow dynamic approximation components, but not fast dynamic detailed components, were linked to pain intensity on postoperative day 30. Despite imbalanced outcome rates, using wavelet decomposition along with a neural network for classification, the model achieved an F score of 0.79 and area under the receiver operating characteristic curve of 0.74 on test-set data for classifying pain intensities on postoperative day 30. The wavelet-based approach outperformed logistic regression (F score of 0.31) and neural network (F score of 0.22) classifiers that were restricted to sociodemographic variables and linear trajectories of pain intensities. CONCLUSIONS: These findings identify latent mechanistic information within the temporal domain of clinically documented acute POP intensity ratings, which are accessible via wavelet analysis, and demonstrate that such temporal patterns inform pain outcomes at postoperative day 30

    Linguistic tone is related to the population frequency of the adaptive haplogroups of two brain size genes, ASPM and Microcephalin

    No full text
    The correlations between interpopulation genetic and linguistic diversities are mostly noncausal (spurious), being due to historical processes and geographical factors that shape them in similar ways. Studies of such correlations usually consider allele frequencies and linguistic groupings (dialects, languages, linguistic families or phyla), sometimes controlling for geographic, topographic, or ecological factors. Here, we consider the relation between allele frequencies and linguistic typological features. Specifically, we focus on the derived haplogroups of the brain growth and development-related genes ASPM and Microcephalin, which show signs of natural selection and a marked geographic structure, and on linguistic tone, the use of voice pitch to convey lexical or grammatical distinctions. We hypothesize that there is a relationship between the population frequency of these two alleles and the presence of linguistic tone and test this hypothesis relative to a large database (983 alleles and 26 linguistic features in 49 populations), showing that it is not due to the usual explanatory factors represented by geography and history. The relationship between genetic and linguistic diversity in this case may be causal: certain alleles can bias language acquisition or processing and thereby influence the trajectory of language change through iterated cultural transmission
    corecore