1,241 research outputs found

    Effects of an 8-year childhood physical activity intervention on musculoskeletal gains and fracture risk

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    Background Physical activity (PA) in childhood is associated with musculoskeletal benefits while the effect on fracture risk is yet to be determined. The aim of this study was to evaluate whether extension of a PA intervention leads to improvement in musculoskeletal traits with an accompanied reduced fracture risk. We hypothesized that the PA program would have beneficial effects in both sexes, but more so in girls since they tend to be less physically active than boys during this time frame. Methods In one elementary school we increased physical education (PE) from 60 to 200 min per school week and followed 65 girls and 93 boys from a mean age of 7 years until a mean age of 15 years. Thirty-nine girls and 37 boys in three other schools continued with 60 min of PE per week during the same years and served as controls. We measured bone mineral content (BMC), areal bone mineral density (aBMD), and bone area annually with dual energy X-ray absorptiometry, and leg muscle strength with a computerized dynamometer. In 3534 children within the same PE program (1339 in the intervention and 2195 in the control group) we registered incident fractures during the 8-year study period and estimated annual sex-specific fracture incidence rate ratios (IRRs). Results Girls in the intervention group annually gained more total body less head aBMD, spine aBMD (p < 0.01), femoral neck BMC (p < 0.05), lumbar vertebrae size (p < 0.05), and knee flexion strength (p < 0.05) than girls in the control cohort. In boys we found no group differences. There was an inverse correlation between number of years with extra PE and the annual IRR of sustaining fractures in both girls (r = − 0.90 (95% CI − 0.98 to − 0.51); p < 0.001) and boys (r = − 0.74 (95% CI − 0.94 to − 0.02); p < 0.05). Conclusion In this 8-year pediatric school-based moderate exercise intervention program there is an inverse correlation in both sexes between annual IRR and each additional year of extra PA. A sub-cohort of girls in the intervention group had greater gains in bone mass, bone size, and muscle strength, which could possibly explain the inverse correlation between years within the PA program and fracture risk, while in boys the reason for the inverse correlation remains unknown. It should be noted that differences in unreported factors such as skeletal maturity status, diet, and spare time PA could confound our inferences. That is, true causality cannot be stated

    Prediction of Outcome After Endovascular Embolectomy in Anterior Circulation Stroke Using Biomarkers

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    Stroke is a major public health problem that can cause a long-term disability or death due to brain damage. Serious stroke is frequently caused by a large vessel occlusion in the anterior circulation, which should be treated by endovascular embolectomy if possible. In this study, we investigated the use of the brain damage biomarkers tau, NFL, NSE, GFAp, and S100B to understand the progression of nervous tissue damage and their relationship to outcome in such stroke after endovascular treatment. Blood samples were taken from 90 patients pre-treatment and 2 h, 24 h, 48 h, 72 h and 3 months after endovascular treatment. Stroke-related neurological deficit was estimated using the National Institute of Health Stroke Scale (NIHSS) at admission and at 24 h. Neurological outcome was evaluated at 3 months. After stroke, tau, NFL, GFAp and S100B increased in a time dependent manner, while NSE remained constant over time. At 3 months, tau and GFAp levels were back to normal whereas NFL was still high. Tau, NFL and GFAp correlated well to outcome, as well as to infarct volume and NIHSS at 24 h. The best time for prediction of poor outcome was different for each biomarker. However, the combination of NIHSS at 24 h with either tau, NFL or GFAp at 48 h gave the best prediction. The use of biomarkers in the early setting after endovascular treatment of stroke will lead to a simplified and standardized way to estimate the nervous tissue damage and possibly complement the clinical judgement in foreseeing the need of rehabilitation measures

    Evolution challenges. Integrating research and practice in teaching and learning about evolution

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    Abstract and Keywords Scientists frequently attribute public misunderstanding of evolution to religious or political influences. Ineffective undergraduate teaching has also contributed. Faculty often ignored strong pedagogical evidence. Five research conclusions are discussed: The traditional lecture approach is inadequate. Active learning is much more effective. Fundamental reasoning difficulties limit students&apos; understanding. Simple steps help overcome these. Misconceptions typically persist unless directly addressed with a conceptual-change approach. Evolution is a complex set of ideas that cannot be adequately understood without advanced critical thinking. This is infrequently mastered without intentionally designed learning tasks. Understanding evolution is typically insufficient for its acceptance. But acceptance as valid for real-world decisions is important. This requires helping students consider social and affective factors related to evolution. Keywords: misconceptions, conceptual-change, intentional design, evolution acceptance Scientists frequently attribute the public misunderstanding of evolution largely to conservative religious influences or dubious political motivations. Indeed, Mazur (2004 found Christian religiosity to be the strongest correlate of &quot;disbelief&quot; in evolution with low educational attainment and political conservatism also important. How science is taught in undergraduate education is a powerful additional factor that usually has been ignored in analyses of Why Don&apos;t Undergraduates Really &quot;Get&quot; Evolution? What Can ... http://www.oxfordscholarship.com.ezproxy.lib.indiana.edu/vie... of 27 6/25/13 5:37 PM public misunderstanding of evolution. Rejection and misunderstanding of evolution are not simply the results of some facets of American culture. Rather, they are also the predictable results of traditional, didactic teaching strategies. Postsecondary science teaching often ignores strong evidence on ways to make instruction much more effective (e.g., The first part of this chapter focuses on four broadly applicable results of research on teaching undergraduate science. The latter part turns to strategies that take account of factors that apply more strongly to evolution than to much of the rest of science. Key Result 1: Active Learning Is More Effective Active learning substantially increases achievement when compared with traditional pedagogy in undergraduate science, a conclusion featured in a review in Science The inadequacy of the traditional lecture approach in undergraduate science has been demonstrated most extensively in physics, where active methods roughly doubled average normalized pretest to posttest gains in learning, an effect approximating a two standard deviation difference Thus, one answer to the question &quot;What can faculty do to increase the proportion of students who &apos;get&apos; evolution?&quot; is to switch further toward structured active learning in lieu of more didactic pedagogies. The implications of this conclusion can be both distressing and elating. This conclusion can be distressing because time already spent on improving lectures would often have been spent much more effectively on improving pedagogy. The conclusion can be elating because changes can be fairly easy and can have large effects. Unfortunately, faculty often have reservations about adopting active learning. These reservations include loss of content coverage, possible loss of control over the class, and possible failure of the activities. Tanner (2009) addressed a number of these. Similarly, several dysfunctional illusions that falsely suggest a lack of rigor for more effective pedagogies probably have slowed their adoption However one chooses to label these reasoning abilities, scores on reasoning tests have often been shown to predict achievement in undergraduate science courses and, sometimes, in precollege science (e.g., These findings have profound implications for understanding and teaching molecular aspects of biology generally, and of evolution specifically, as shown by studies of undergraduate chemistry. For example, Herron (1975) listed startling differences between core ideas in chemistry that the concrete students can and cannot understand without altered pedagogy. These students will be a large fraction of any first-year class. (p.314) Scores on reasoning tests were also related to the acceptance of evolution. Students who scored lower on tests of basic reasoning were less likely to accept evolution on the pretest and were more likely to continue to reject evolution on the posttest than individuals who performed better on the reasoning assessment A major advance for understanding how differences in reasoning play out in learning biology was recently provided by 1. Descriptive predictions could be mastered by most students whatever their scores on reasoning tests. 2. Tasks requiring understanding and testing hypotheses involving perceptible causal agents (e.g., light, moisture) were usually mastered only by students with higher reasoning scores. 3. Tasks using hypotheses involving causal agents that cannot be as directly perceived (e.g., genetic versus environmental causation, chemical communication) were usually mastered only by students with even higher reasoning abilities. Much greater pedagogical support is needed for tasks requiring the use of causal hypotheses, especially those using inferred causal agents. These distinctions are fundamental to students&apos; difficulties in understanding evolution and to the development of effective ways to help them master it. Unfortunately, the underlying reasoning patterns are not changed easily with conventional teaching. Other researchers have made additional suggestions for fostering more complex reasoning. For example, a nice example of the use of hands-on modeling to support more complex thinking in a large molecular biology class was provided by In summary, the answer to the question &quot;What can faculty do to increase the proportion of students who &apos;get&apos; evolution?&quot; from this second perspective is that faculty often need to pay more attention to students&apos; basic reasoning and to teach in ways that better support (rather than just require) scientific understanding and reasoning. Without such support many students cannot understand what is being taught even when they are trying quite hard to do so. Although these problems and many of the solutions have been clear for decades, they have not been widely adopted. &quot;Because we [as faculty] are at the point that concrete experience … is superfluous, we tend to forget that it was not always so [for us] and in our rush to &apos;cover the material,&apos; we omit the very kind of experiences that can make our subject meaningful to beginning students&quot; (Herron, 1978, p. 167). Many faculty will be skeptical (as I was) that well-performing students are deficient in understanding the basic concepts that should underlie their successes in class. It may be hard to accept that even &quot;facility in solving standard quantitative problems is not an adequate criterion for functional understanding&quot; (Thornton, 1999). In order to see the limitations of current approaches and the effects of changes we need more sophisticated ways of writing in-class and exam assessments About the Index Search across all sources Show related links Why Don&apos;t Undergraduates Really &quot;Get&quot; Evolution? What Can ... http://www.oxfordscholarship.com.ezproxy.lib.indiana.edu/vie... of 27 6/25/13 5:37 PM macroevolution is central to an understanding of the strength of the evidence showing that evolution has occurred (Padian, 2010). Further, macroevolution &quot;is perhaps the primary stumbling block&quot; for students, teachers, and other adults who have difficulty accepting evolution (M. U. Smith, 2010b, p. 541). The switch in students&apos; understanding from misconceptions or alternative conceptions to scientifically valid views is termed conceptual change (for evolution: Banet &amp; Ayuso, 2003; Various approaches to teaching evolution have attempted to produce major conceptual change and understanding generally. M. U. Smith (2010b) provided a concise (p.317) overview. Six examples merit special discussion. Although these mostly address microevolution, they could be modified for topics in macroevolution. 1. An Exemplary Conceptual Change Approach. Banet and Ayuso About the Index Search across all sources Show related links Why Don&apos;t Undergraduates Really &quot;Get&quot; Evolution? What Can ... http://www.oxfordscholarship.com.ezproxy.lib.indiana.edu/vie... of 27 6/25/13 5:37 PM Roscoe, this volume). 5. Participatory Action Research. In a multiyear study, Grant (2008) examined the misconceptions his first-year biology students held about natural selection. &quot;Many students who presented evidence on pre-tests that they harbored substantial misconceptions in fact remained highly resistant to instruction, and often defended their misconceptions using course appropriate terminology, but incorrectly, on the course final exam. In other words, many had hijacked course content in service of their misconceptions&quot; (Grant, 2008, p. 15). He iteratively designed ways to address these in a large class setting. Key changes included repeatedly presenting summaries of in-class surveys of prior knowledge and misconceptions. He also asked students to discuss with their neighbors what evidence and arguments would be needed to foster the replacement of these misconceptions with expert knowledge. He termed this &quot;participatory action research.&quot; It required substantial reductions in content and rearrangements of topics. There were large increases over previous years in the grades on the final examination questions on evolution: On a key question assessing natural selection, good answers (8 to10 of 10 points) increased from about 3% of students (2000)(2001)(2002)(2003)(2004)(2005) to 54% (2006)(2007), and very low scores (0-2 points) were eliminated. This approach has considerable promise for improving undergraduate science learning generally. Whole Course Transformation. In what is essentially a deep conceptual change approach, BioQUEST has emphasized computer-facilitated, case-based learning with a focus on problem-posing, problem-solving, and peer persuasion, often addressing topics in evolution In summary, the answer to the question &quot;What can faculty do to increase the proportion of students who &apos;get&apos; evolution?&quot; from this third perspective is that faculty often need to give even more attention to students&apos; persistent misunderstandings and to teach in ways that better support conceptual change (rather than falsely assuming that telling students the right idea or showing them the data will be sufficient to elicit change). Without explicit, active support for conceptual change, most students will retain their initial misunderstandings. (p.319) Key Result 4: Complex Thinking Is Requisite for Understanding Evolution Many of the difficulties we encounter in getting students to understand evolution are well explained by differences in their approaches to knowledge, specifically to how they expect to understand new topics. These approaches range from &quot;just tell me what to memorize&quot; to expecting us to help them understand the applications, implications, and trade-offs in various contexts. These different approaches are usefully understood as differences in adult cognitive development. There is a substantial body of research on cognitive development in college and its implications for learning and teaching. This approach began with Perry&apos;s (1970) study of &quot;intellectual and ethical development&quot; in undergraduates. Perry&apos;s work has been cited by hundreds of subsequent studies (partially reviewed by Cognitive development beyond that typically found in undergraduates is a prerequisite for an adequate understanding of evolution. Sinatra, Southerland, McConaughy, and Demastes About the Index Search across all sources Show related links Why Don&apos;t Undergraduates Really &quot;Get&quot; Evolution? What Can ... http://www.oxfordscholarship.com.ezproxy.lib.indiana.edu/vie... 6 of 27 6/25/13 5:37 PM they termed absolutism, relativism, and evaluativism. Perry&apos;s terms for these three approaches (dualism, multiplicity, and relativism) have been widely used, although some studies have used alternative terminologies. A simplified summary of these major cognitive differences will make clearer the implications for teaching evolution. (p.320) Absolutism (Perry&apos;s Dualism) About two-thirds of first-year students and half of sophomores had absolutism as their core approach Relativism (Perry&apos;s Multiplicity) When students first encounter meaningful uncertainty in a new area they typically have no idea how it might be resolved. In the face of uncertainty all opinions seem to be equally valid-any answer that one prefers on whatever grounds is fine. Personal experience, personally interpreted, has the preeminent role. This is the approach most of us usually use in picking a flavor of ice cream, but it is a terrible approach to critical thinking About one-third of first-year students and perhaps 80% of seniors were &quot;transitional&quot;: they regarded knowledge in some areas as absolute and knowledge in others as uncertain and, hence, arbitrary Burgoyne and Downey (2011) have suggested that we ask students to see absolutism and relativism as two misconceptions: Contextual Knowing (Bendixen and Rule&apos;s Evaluativism; Perry&apos;s Relativism) The approach where students have learned to make context-framed, criteria-based comparisons has also been termed contextual relativism (e.g., Knefelkamp, 1999) (p.321) and contextual knowing As students become more cognitively sophisticated, they (like many older adults) typically use a mosaic of approaches, perhaps treating some topics in dualism/absolutism and some in multiplicity even while struggling to master contextual knowing in others Beyond Contextual Knowing The limitations of simple contextual knowing are evident when we consider complex problems. The core difficulty is that students who have learned to operate within a series of individual disciplines often have no coherent way to deal with differences that arise when a variety of disciplines apply to a complex problem. They consequently see any choice among combinations of disciplinary For example, even a local environmental issue, such as the appropriateness of a nuclear power plant, requires a consideration of trade-offs across multiple perspectives including science, waste disposal, environmental economics, politics, and environmental racism, to name just a few To deal with such issues constructively, students must learn to consider the benefits and negative consequences illuminated by each perspective. As students learn to make such analyses they begin thinking in a way that Perry termed &quot;Commitment [within contextual relativism]&quot; and Baxter Magolda termed &quot;self-authorship.&quot; This approach is exceedingly rare among undergraduates except under transformed curricula Applications to Teaching Evolution &quot;Perhaps the most useful developmental theory to be applied to evolution instruction is that of Perry&quot; (M. U. Smith, 2010b, p. 541; also Nelson, 1986, etc.). Classroom applications that strive to foster cognitive development can profitably focus on key aspects of the three transitions between the four main approaches to understanding. (p.322) These are: initially understanding uncertainty, then using comparisons and criteria to address uncertainty (contextual knowing) and, later, using consequences and values to frame arguments and justify choices. Uncertainty in evolution can be invoked, for example, by listing (or having the class list) currently viable alternative hypotheses, listing ones that were historically viable or by asking for deep understanding of experimental designs (Why is this control included? Are any controls missing? What untested hypotheses might have produced the same results?). Once some important uncertainty has been made clear, the alternative hypotheses or design considerations or other factors need to be compared, and possibly resolved, using appropriate criteria. Unless both the alternatives and the criteria are made explicit, most of the critical thinking will be tacit and therefore incomprehensible-and the students&apos; approaches to thinking will be unaffected. For comparisons of historically grounded alternatives in evolution, such as what sequences should have been expected from the fossil record, an appropriate criterion is the result of a fair test. A fair test is a new set of data that could have confirmed any of the alternatives and that is different from (and not tightly tied to) the data sets on which they were proposed. We can ask: What patterns of change in the fossil record might have been expected of the fossil record when the geological column was first put into its modern order in the 1840s, noting that evolution was not really available except to Darwin. Alternatives included: all kinds at the beginning with just extinction, Lyell&apos;s large cycles with great reptiles perhaps returning again (and again), Sedgwick&apos;s extinctions and new recreations, vertebrates first and invertebrates by degeneration, and, of course, evolution starting, as Darwin noted, with one or a few very simple kinds. Students will suggest some of these ideas, if asked. The fossil record itself provides a fair test of these alternatives, as most of them were not based on the ordered sequence of rocks in the newly emerging geological column and as any of the alternative patterns could have been found. A number of other criteria are also important. These include accounting for apparently conflicting scientific data and the availability of causal explanations (e.g., However, even when we understand that one alternative is much more probable than another we may choose not to accept it. It is often appropriate to reject hypotheses that are probably true when there are serious risks to accepting the hypothesis and being wrong. Thus, for many considerations of safety in the face of severe consequences we demand not just that safety be very probable but that it be overwhelmingly probable (basic decision theory, below). This requires moving beyond contextual knowing. For students studying evolution, going beyond contextual knowing would require that students understand the force of the evidence in the context of the nature of science generally; understand and know how to weigh the consequences (p.323) from the applications of evolution, both positive and negative; and understand how to fit evolution into larger cultural contexts. It thus becomes crucial for faculty members who teach evolution to help students address its consequences and applications. Faculty also need to consider whether to address the cultural contexts for evolution and, if so, how to do so effectively. About the Index Search across all sources Show related links Why Don&apos;t Undergraduates Really &quot;Get&quot; Evolution? What Can ... http://www.oxfordscholarship.com.ezproxy.lib.indiana.edu/vie... of 27 6/25/13 5:37 PM If we step back from focusing just on conceptual understanding or scientific reasoning, things become more complicated. Baxter Magolda (e.g., 2004a) noted that students make meaning of their experiences using their own perspectives rather than accepting the instructor&apos;s meaning and perspective. Further, the development of more complex ways of understanding is inextricably intertwined with the development of a different and more complex sense of self and of different and of more complex ways of relating to others. &quot;Interviewees who developed complex ways of knowing [after graduation] often could not live those ways of knowing until they had developed complex ways of seeing themselves and their relations with others&quot; (Baxter Magolda, 2004a, p. 39). Let me stress again the importance of making extensive use of structured active learning and not just because it fosters content mastery. Appropriately structured collaborative and cooperative learning also helps foster increased cognitive sophistication and the other changes that are essential to that cognitive development. I found two techniques to be especially powerful in fostering cognitive development: 1. In teaching evolution to seniors, I developed a worksheet based on Perry&apos;s descriptions of the cognitive tasks required for deep understanding (Nelson, 2010a), and had students complete the worksheet outside of class. Then, I implemented a whole-period discussion of applications of Perry&apos;s principles, a discussion that fostered deep rethinking with peers. 2. In courses ranging from first-year to graduate, I had the students either discuss excerpts from Perry&apos;s (1970) book including his summary of the student&apos;s experience (Nelson, 2010a) or presented and had them discuss and repeatedly refer back to a graphical synopsis of Perry (as in Nelson, 2010b). Using either approach, I repeatedly asked students how a person would respond to the evolution-creation controversy (and to other issues) from the perspective of an absolutist, versus from multiplicity, versus, in turn, from contextual knowing and, later, from self-authorship In summary, the answer to the question &quot;What can faculty do to increase the proportion of students who &apos;get&apos; evolution?&quot; from this fourth perspective is that faculty need to design their courses to foster greater cognitive sophisticati

    Paradigms of flexibility: a systematic review of research on workplace flexibility

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    As flexibility has become a sine-qua-non of the contemporary workplace, we performed a critical review of its different uses and understandings in business and management research. Analyzing the literature on workplace flexibility in the period 1970-2018, using a four-part conceptual framework, and on the basis of subsequent content analysis of 262 most relevant publications, we identify two axes of tension embedding scholarly work on flexibility: the flexibility of vs. flexibility for organizations and employees, and a favorability-criticality tension. We further explain how internal divisions are attributable to three different paradigms of flexibility (two of which dominate), resulting from divergent sets of assumptions regarding: its target, rationale, approach to it, as well as methodologies involved in studying it. We propose a research agenda indicating the ways in which paradigmatic underpinnings of flexibility research may be further clarified and divisions between the paradigms made sense of

    Coulomb gap in a model with finite charge transfer energy

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    The Coulomb gap in a donor-acceptor model with finite charge transfer energy Δ\Delta describing the electronic system on the dielectric side of the metal-insulator transition is investigated by means of computer simulations on two- and three-dimensional finite samples with a random distribution of equal amounts of donor and acceptor sites. Rigorous relations reflecting the symmetry of the model presented with respect to the exchange of donors and acceptors are derived. In the immediate neighborhood of the Fermi energy μ\mu the the density of one-electron excitations g(ϵ)g(\epsilon) is determined solely by finite size effects and g(ϵ)g(\epsilon) further away from μ\mu is described by an asymmetric power law with a non-universal exponent, depending on the parameter Δ\Delta.Comment: 10 pages, 6 figures, submitted to Phys. Rev.

    Wilson function transforms related to Racah coefficients

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    The irreducible ∗*-representations of the Lie algebra su(1,1)su(1,1) consist of discrete series representations, principal unitary series and complementary series. We calculate Racah coefficients for tensor product representations that consist of at least two discrete series representations. We use the explicit expressions for the Clebsch-Gordan coefficients as hypergeometric functions to find explicit expressions for the Racah coefficients. The Racah coefficients are Wilson polynomials and Wilson functions. This leads to natural interpretations of the Wilson function transforms. As an application several sum and integral identities are obtained involving Wilson polynomials and Wilson functions. We also compute Racah coefficients for U_q(\su(1,1)), which turn out to be Askey-Wilson functions and Askey-Wilson polynomials.Comment: 48 page

    Ising Universality in Three Dimensions: A Monte Carlo Study

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    We investigate three Ising models on the simple cubic lattice by means of Monte Carlo methods and finite-size scaling. These models are the spin-1/2 Ising model with nearest-neighbor interactions, a spin-1/2 model with nearest-neighbor and third-neighbor interactions, and a spin-1 model with nearest-neighbor interactions. The results are in accurate agreement with the hypothesis of universality. Analysis of the finite-size scaling behavior reveals corrections beyond those caused by the leading irrelevant scaling field. We find that the correction-to-scaling amplitudes are strongly dependent on the introduction of further-neighbor interactions or a third spin state. In a spin-1 Ising model, these corrections appear to be very small. This is very helpful for the determination of the universal constants of the Ising model. The renormalization exponents of the Ising model are determined as y_t = 1.587 (2), y_h = 2.4815 (15) and y_i = -0.82 (6). The universal ratio Q = ^2/ is equal to 0.6233 (4) for periodic systems with cubic symmetry. The critical point of the nearest-neighbor spin-1/2 model is K_c=0.2216546 (10).Comment: 25 pages, uuencoded compressed PostScript file (to appear in Journal of Physics A

    Spin chains with dynamical lattice supersymmetry

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    Spin chains with exact supersymmetry on finite one-dimensional lattices are considered. The supercharges are nilpotent operators on the lattice of dynamical nature: they change the number of sites. A local criterion for the nilpotency on periodic lattices is formulated. Any of its solutions leads to a supersymmetric spin chain. It is shown that a class of special solutions at arbitrary spin gives the lattice equivalents of the N=(2,2) superconformal minimal models. The case of spin one is investigated in detail: in particular, it is shown that the Fateev-Zamolodchikov chain and its off-critical extension admits a lattice supersymmetry for all its coupling constants. Its supersymmetry singlets are thoroughly analysed, and a relation between their components and the weighted enumeration of alternating sign matrices is conjectured.Comment: Revised version, 52 pages, 2 figure

    Glucosylsphingosine Is a Highly Sensitive and Specific Biomarker for Primary Diagnostic and Follow-Up Monitoring in Gaucher Disease in a Non-Jewish, Caucasian Cohort of Gaucher Disease Patients

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    Gaucher disease (GD) is the most common lysosomal storage disorder (LSD). Based on a deficient β-glucocerebrosidase it leads to an accumulation of glucosylceramide. Standard diagnostic procedures include measurement of enzyme activity, genetic testing as well as analysis of chitotriosidase and CCL18/PARC as biomarkers. Even though chitotriosidase is the most well-established biomarker in GD, it is not specific for GD. Furthermore, it may be false negative in a significant percentage of GD patients due to mutation. Additionally, chitotriosidase reflects the changes in the course of the disease belatedly. This further enhances the need for a reliable biomarker, especially for the monitoring of the disease and the impact of potential treatments.Here, we evaluated the sensitivity and specificity of the previously reported biomarker Glucosylsphingosine with regard to different control groups (healthy control vs. GD carriers vs. other LSDs).Only GD patients displayed elevated levels of Glucosylsphingosine higher than 12 ng/ml whereas the comparison controls groups revealed concentrations below the pathological cut-off, verifying the specificity of Glucosylsphingosine as a biomarker for GD. In addition, we evaluated the biomarker before and during enzyme replacement therapy (ERT) in 19 patients, demonstrating a decrease in Glucosylsphingosine over time with the most pronounced reduction within the first 6 months of ERT. Furthermore, our data reveals a correlation between the medical consequence of specific mutations and Glucosylsphingosine.In summary, Glucosylsphingosine is a very promising, reliable and specific biomarker for GD
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