Useful Diagnostic (useful + diagnostic)

Distribution by Scientific Domains

Terms modified by Useful Diagnostic

  • useful diagnostic marker
  • useful diagnostic tool

  • Selected Abstracts

    13C-breath tests for clinical investigation of liver mitochondrial function

    Ignazio Grattagliano
    Eur J Clin Invest 2010; 40 (9): 843,850 Abstract Background, Mitochondria play a major role in cell energetic metabolism; therefore, mitochondrial dysfunction inevitably participates in or even determines the onset and progression of chronic liver diseases. The assessment of mitochondrial function in vivo, by providing more insight into the pathogenesis of liver diseases, would be a helpful tool to study specific hepatic functions and to develop rational diagnostic, prognostic and therapeutic strategies. Design, This review focuses on the utility of breath tests to assess mitochondrial function in humans and experimental animals. Results, The introduction in the clinical setting of specific breath tests may allow elegantly and noninvasively overcoming the difficulties caused by previous complex techniques and might provide clinically relevant information, i.e the effects of drugs on mitochondria. Substrates meeting this requirement are alpha-keto-isocaproic acid and methionine that are both decarboxylated by mitochondria. Long-and medium-chain fatty acids that are metabolized through the Krebs cycle, and benzoic acid which undergoes glycine conjugation, may also reflect the function of mitochondria. Conclusions, Breath tests to assess in vivo mitochondrial function in humans represent a potentially useful diagnostic and prognostic tool in clinical investigation. [source]

    The behaviour of soil process models of ammonia volatilization at contrasting spatial scales

    R. Corstanje
    Summary Process models are commonly used in soil science to obtain predictions at a spatial scale that is different from the scale at which the model was developed, or the scale at which information on model inputs is available. When this happens, the model and its inputs require aggregation or disaggregation to the application scale, and this is a complex problem. Furthermore, the validity of the aggregated model predictions depends on whether the model describes the key processes that determine the process outcome at the target scale. Different models may therefore be required at different spatial scales. In this paper we develop a diagnostic framework which allows us to judge whether a model is appropriate for use at one or more spatial scales both with respect to the prediction of variations at those scale and in the requirement for disaggregation of the inputs. We show that spatially nested analysis of the covariance of predictions with measured process outcomes is an efficient way to do this. This is applied to models of the processes that lead to ammonia volatilization from soil after the application of urea. We identify the component correlations at different scales of a nested scheme as the diagnostic with which to evaluate model behaviour. These correlations show how well the model emulates components of spatial variation of the target process at the scales of the sampling scheme. Aggregate correlations were identified as the most pertinent to evaluate models for prediction at particular scales since they measure how well aggregated predictions at some scale correlate with aggregated values of the measured outcome. There are two circumstances under which models are used to make predictions. In the first case only the model is used to predict, and the most useful diagnostic is the concordance aggregate correlation. In the second case model predictions are assimilated with observations which should correct bias in the prediction, and errors in the variance; the aggregate correlations would be the most suitable diagnostic. [source]

    Cross-National Concepts in Supranational Governance: State,Society Relations and EU Policy Making

    GOVERNANCE, Issue 4 2004
    Albert S. YeeArticle first published online: 25 AUG 200
    The emergence of multiple and shifting modes of governance both intranationally and supranationally has posed difficulties for analysts accustomed to refining or testing singular types of politics. When confronted with this changing complexity, a comprehensive framework can be a very useful diagnostic and organizational tool. This article devises one such conceptual framework to clarify and systematize varieties of state autonomy and state,society relations. By combining fundamental conceptions of action, elemental control mechanisms, and basic types of interaction, a comprehensive framework is constructed for characterizing and comparing governance modes in a conceptually coherent manner. Many of the abstract spaces within this conceptual field share affinities with types of state autonomy and state,society relations depicted in major theoretical approaches to national politics (i.e., authoritarianism, statism, pluralism, corporatism, institutionalism, and Marxism). This article uses this conceptual framework to systematize these major governance modes and to illuminate their coexistence in supranational governance by examining the European Union policy process. [source]

    Spinal somatosensory evoked potential evaluation of acute nerve-root injury associated with pedicle-screw placement procedures: An experimental study

    I-Ming Jou
    Pedicle screws for spinal fixation risk neural damage because of the proximity between screw and nerve root. We assessed whether spinal somatosensory evoked potential (SSEP) could selectively detect pedicle-screw-related acute isolated nerve injury. Because pedicle screws are too large for a rat's spine, we inserted a K-wire close to the pedicle in 32 rats, intending not to injure the nerve root in eight (controls), and to injure the L4 or L5 root in 24. We used sciatic-nerve-elicited SSEP pre- and postinsertion. Radiologic, histologic, and postmortem observations confirmed the level and degree of root injury. Sciatic (SFI), tibial (TFI), and peroneal function indices (PFI) were calculated and correlated with changes in potential. Although not specific for injuries to different roots, amplitude reduction immediately postinsertion was significant in the experimental groups. Animals with the offending wire left in place for one hour showed a further non-significant deterioration of amplitude. Electrophysiologic changes correlated with SFI and histologic findings in all groups. SSEP monitoring provided reliable, useful diagnostic and intraoperative information about the functional integrity of single nerve-root injury. These findings are clinically relevant to acute nerve-root injury and pedicle-screw insertion. If a nerve-root irritant remains in place, a considerable neurologic deficit will occur. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source]

    Using gene chips to identify organ-specific, smooth muscle responses to experimental diabetes: potential applications to urological diseases

    BJU INTERNATIONAL, Issue 2 2007
    Jason D. Hipp
    OBJECTIVE To identify early diabetes-related alterations in gene expression in bladder and erectile tissue that would provide novel diagnostic and therapeutic treatment targets to prevent, delay or ameliorate the ensuing bladder and erectile dysfunction. MATERIALS AND METHODS The RG-U34A rat GeneChip® (Affymetrix Inc., Sunnyvale, CA, USA) oligonucleotide microarray (containing ,8799 genes) was used to evaluate gene expression in corporal and male bladder tissue excised from rats 1 week after confirmation of a diabetic state, but before demonstrable changes in organ function in vivo. A conservative analytical approach was used to detect alterations in gene expression, and gene ontology (GO) classifications were used to identify biological themes/pathways involved in the aetiology of the organ dysfunction. RESULTS In all, 320 and 313 genes were differentially expressed in bladder and corporal tissue, respectively. GO analysis in bladder tissue showed prominent increases in biological pathways involved in cell proliferation, metabolism, actin cytoskeleton and myosin, as well as decreases in cell motility, and regulation of muscle contraction. GO analysis in corpora showed increases in pathways related to ion channel transport and ion channel activity, while there were decreases in collagen I and actin genes. CONCLUSIONS The changes in gene expression in these initial experiments are consistent with the pathophysiological characteristics of the bladder and erectile dysfunction seen later in the diabetic disease process. Thus, the observed changes in gene expression might be harbingers or biomarkers of impending organ dysfunction, and could provide useful diagnostic and therapeutic targets for a variety of progressive urological diseases/conditions (i.e. lower urinary tract symptoms related to benign prostatic hyperplasia, erectile dysfunction, etc.). [source]