1,511 research outputs found

    Purification of all thirteen polypeptides of bovine heart cytochrome c oxidase from one aliquot of enzyme Characterization of bovine fetal heart cytochrome c oxidase

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    AbstractA protocol has been worked out for separating all thirteen different polypeptides in the beef heart cytochrome c oxidase complex from a single aliquot of enzyme. This involves an initial separation of polypeptides by gel filtration on a Biogel P-60 column in SDS, a step which purifies subunits CIV and CVIII and gives mixtures of CV+CVI, ASA, AED and STA, as well as CVII, CIX and IHQ. These mixtures are then resolved by reverse-phase high-performance liquid chromatography. The separation procedures have been applied to fetal heart cytochrome c oxidase of gestation between 100 and 200 days. No differences were found in the N-terminal sequences of any of the cytoplasmically made subunits or in the entire sequence of CIX between late fetal and adult forms of the enzyme

    Quantitative proteomics: the copy number of pyruvate dehydrogenase is more than 102-fold lower than that of complex III in human mitochondria

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    AbstractPyruvate dehydrogenase (PDH) and complex III are two key protein complexes in mitochondrial metabolic activity. Using a novel quantitative Western blotting method, we find that PDH and complex III exist at a steady-state ratio of 1:100, 1:128 and 1:202 in HeLa cell extracts, fibroblast mitochondria and heart tissue mitochondria, respectively. This difference in stoichiometry is reflected in the immunogold labeling intensities of the two complexes and by the much more sparse distribution of PDH in fluorescence microscopy. In Rho0 fibroblasts there is a 64% reduction of complex III but the concentration of PDH remains the same as wild-type

    A cryoelectron microscopy study of the interaction of the Escherichia coli F1-ATPase with subunit b dimer

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    AbstractA complex between the Escherichia coli F1-ATPase and a truncated form of the ECF0-b subunit was formed and examined by cryoelectron microscopy in amorphous ice. Image analysis of single particles in the hexagonal projection revealed that the polar domain of the b subunit interacts with a β subunit different from the one which interacts with the ϵ subunit. The cavity in the enzyme, visible in the hexagonal projection, is not filled by the b polypeptide, therefore leaving enough room for extensive conformational changes of the γ and ϵ subunits within the native F1F0 complex

    An improved purification of ECF1 and ECF1F0 by using a cytochrome bo-deficient strain of Escherichia coli facilitates crystallization of these complexes

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    AbstractA novel strategy, which employs a cytochrome bo-lacking strain (GO104) and a modified isolation procedure provides an effective approach for obtaining much purer preparations of ECF1F0 than described previously, as well as for isolating homogeneous and protein-chemically pure ECF1. ECF1 obtained in this way could be crystallized by vapor-diffusion using polyethylene glycol (PEG) as a precipitant in a form suitable for X-ray diffraction analysis. The crystals belong to the orthorhombic space group P212121, with lattice parameters a=110, b=134, and c=269 Ã…, and diffract to a resolution of at least 6.4 Ã…

    Magnetic resonance imaging biomarkers of chronic obstructive pulmonary disease prior to radiation therapy for non-small cell lung cancer.

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    OBJECTIVE: In this prospectively planned interim-analysis, the prevalence of chronic obstructive lung disease (COPD) phenotypes was determined using magnetic resonance imaging (MRI) and X-ray computed tomography (CT) in non-small-cell-lung-cancer (NSCLC) patients. MATERIALS AND METHODS: Stage-III-NSCLC patients provided written informed consent for pulmonary function tests, imaging and the 6-min-walk-test. Ventilation defect percent (VDP) and CT lung density (relative-of-CT-density-histogram RESULTS: Seventeen stage-III NSCLC patients were evaluated (68 ± 7 years, 7 M/10 F, mean FEV1 = 77%pred) including seven current and 10 ex-smokers and eight patients with a prior lung disease diagnosis. There was a significant difference for smoking history (p = .02) and FEV1/FVC (p = .04) for subgroups classified using quantitative imaging. Patient subgroups classified using qualitative imaging findings were significantly different for emphysema (RA950, p \u3c .001). There were significant relationships for whole-lung VDP (p \u3c .05), but not RECIST or tumour-lobe VDP measurements with pulmonary function and exercise measurements. Preliminary analysis for non-tumour burden ventilation abnormalities using Reader-operator-characteristic (ROC) curves reflected a 94% classification rate for smoking pack-years, 93% for FEV1/FVC and 82% for RA950. ROC sensitivity/specificity/positive/negative likelihood ratios were also generated for pack-years, (0.92/0.80/4.6/0.3), FEV1/FVC (0.92/0.80/4.6/0.3), RA950 (0.92/0.80/4.6/0.3) and RECIST (0.58/0.80/2.9/1.1). CONCLUSIONS: In this prospectively planned interim-analysis of a larger clinical trial, NSCLC patients were classified based on COPD imaging phenotypes. A proof-of-concept evaluation showed that FEV1/FVC and smoking history identified NSCLC patients with ventilation abnormalities appropriate for functional lung avoidance radiotherapy

    Flourishing in nature: A review of the benefits of connecting with nature and its application as a wellbeing intervention

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    From the increasing number of people living in urban areas to the continued degradation of the natural environment, many of us appear to be physically and psychologically disconnected from nature. We consider the theoretical explanations and present evidence for why this state of affairs might result in suboptimal levels of hedonic and eudaimonic wellbeing by reviewing the large body of research on the mental health benefits of connecting with nature. The advantages of contact with nature as a potential wellbeing intervention are discussed, and examples of how this research is being applied to reconnect individuals to nature and improve wellbeing are given. We conclude by considering the limitations of, and proposing future directions for, research in this area. Overall, evidence suggests that connecting with nature is one path to flourishing in life

    Psychologizing indexes of societal progress: Accounting for cultural diversity in preferred developmental pathways

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    Since the Second World War, the dominating paradigm of societal development has focused on economic growth. While economic growth has improved the quality of human life in a variety of ways, we posit that the identification of economic growth as the primary societal goal is culture-blind because preferences for developmental pathways likely vary between societies. We argue that the cultural diversity of developmental goals and the pathways leading to these goals could be reflected in a culturally sensitive approach to assessing societal development. For the vast majority of post-materialistic societies, it is an urgent necessity to prepare culturally sensitive compasses on how to develop next, and to start conceptualizing growth in a more nuanced and culturally responsive way. Furthermore, we propose that cultural sensitivity in measuring societal growth could also be applied to existing development indicators (e.g. the Human Development Index). We call for cultural researchers, in cooperation with development economists and other social scientists, to prepare a new cultural map of developmental goals, and to create and adapt development indexes that are more culturally sensitive. This innovation could ultimately help social planners understand the diverse pathways of development and assess the degree to which societies are progressing in a self-determined and indigenously valued manner.info:eu-repo/semantics/acceptedVersio

    Conclusions

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    What is the function of parent–child argumentation? This chapter intends to answer the main research question that has guided the study presented in this volume and open a discussion for future research on this topic. In the first part, the chapter provides a detailed overview of the main findings of the analysis of parent–child argumentative discussions during mealtime. The role played by parents and children in the inception and development of argumentation, and the types of conclusions of their argumentative discussions are described. Subsequently, two educational targets achieved by parents and children through their argumentative interactions are presented and critically discussed. In the last part, new open questions that should guide future investigation to expand our knowledge of the role and function of argumentation between parents and children are proposed
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