797 research outputs found

    Noninvasive Prenatal Diagnosis for Cystic Fibrosis: Implementation, Uptake, Outcome, and Implications

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    BACKGROUND: Noninvasive prenatal diagnosis (NIPD) for monogenic disorders has a high uptake by families. Since 2013, our accredited public health service laboratory has offered NIPD for monogenic disorders, predominantly for de novo or paternally dominantly inherited mutations. Here we describe the extension of this service to include definitive NIPD for a recessive condition, cystic fibrosis (CF). // METHODS: Definitive NIPD for CF was developed using next-generation sequencing. Validation was performed on 13 cases from 10 families before implementation. All cases referred for CF NIPD were reviewed to determine turnaround times, genotyping results, and pregnancy outcomes. // RESULTS: Of 38 referrals, 36 received a result with a mean turnaround of 5.75 days (range, 3-11 days). Nine cases were initially inconclusive, with 3 reported unaffected because the low-risk paternal allele was inherited and 4 cases in which the high-risk paternal allele was inherited, receiving conclusive results following repeat testing. One case was inconclusive owing to a paternal recombination around the mutation site, and one case was uninformative because of no heterozygosity. Before 2016, 3 invasive referrals for CF were received annually compared with 38 for NIPD in the 24 months since offering a definitive NIPD service. // CONCLUSIONS: Timely and accurate NIPD for definitive prenatal diagnosis of CF is possible in a public health service laboratory. The method detects recombinations, and the service is well-received as evidenced by the significant increase in referrals. The bioinformatic approach is gene agnostic and will be used to expand the range of conditions tested for

    Challenges and New Approaches to Proving the Existence of Muscle Synergies of Neural Origin

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    Muscle coordination studies repeatedly show low-dimensionality of muscle activations for a wide variety of motor tasks. The basis vectors of this low-dimensional subspace, termed muscle synergies, are hypothesized to reflect neurally-established functional muscle groupings that simplify body control. However, the muscle synergy hypothesis has been notoriously difficult to prove or falsify. We use cadaveric experiments and computational models to perform a crucial thought experiment and develop an alternative explanation of how muscle synergies could be observed without the nervous system having controlled muscles in groups. We first show that the biomechanics of the limb constrains musculotendon length changes to a low-dimensional subspace across all possible movement directions. We then show that a modest assumption—that each muscle is independently instructed to resist length change—leads to the result that electromyographic (EMG) synergies will arise without the need to conclude that they are a product of neural coupling among muscles. Finally, we show that there are dimensionality-reducing constraints in the isometric production of force in a variety of directions, but that these constraints are more easily controlled for, suggesting new experimental directions. These counter-examples to current thinking clearly show how experimenters could adequately control for the constraints described here when designing experiments to test for muscle synergies—but, to the best of our knowledge, this has not yet been done

    Effects of hydroxyapatite and PDGF concentrations on osteoblast growth in a nanohydroxyapatite-polylactic acid composite for guided tissue regeneration

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    The technique of guided tissue regeneration (GTR) has evolved over recent years in an attempt to achieve periodontal tissue regeneration by the use of a barrier membrane. However, there are significant limitations in the currently available membranes and overall outcomes may be limited. A degradable composite material was investigated as a potential GTR membrane material. Polylactic acid (PLA) and nanohydroxyapatite (nHA) composite was analysed, its bioactive potential and suitability as a carrier system for growth factors were assessed. The effect of nHA concentrations and the addition of platelet derived growth factor (PDGF) on osteoblast proliferation and differentiation was investigated. The bioactivity was dependent on the nHA concentration in the films, with more apatite deposited on films containing higher nHA content. Osteoblasts proliferated well on samples containing low nHA content and differentiated on films with higher nHA content. The composite films were able to deliver PDGF and cell proliferation increased on samples that were pre absorbed with the growth factor. nHA–PLA composite films are able to deliver active PDGF. In addition the bioactivity and cell differentiation was higher on films containing more nHA. The use of a nHA–PLA composite material containing a high concentration of nHA may be a useful material for GTR membrane as it will not only act as a barrier, but may also be able to enhance bone regeneration by delivery of biologically active molecules

    Do Web-Based Interventions Improve Well-Being in Type 2 Diabetes? A Systematic Review and Meta-Analysis

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    BACKGROUND: Poor diabetes self-care can have a negative impact on psychological well-being and quality of life. Given the scarcity of traditional psychological support and the barriers to uptake of and attendance at face-to-face education programs, Web-based interventions are becoming a popular approach to provide an additional platform for psychological support in long-term conditions. However, there is limited evidence to assess the effect of Web-based psychological support in people with type 2 diabetes. OBJECTIVE: This systematic review is the first review to critically appraise and quantify the evidence on the effect of Web-based interventions that aim to improve well-being in people with type 2 diabetes. METHODS: Searches were carried out in the following electronic databases: MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane Library. Reference lists were hand-searched. A meta-analysis was conducted for depression and distress outcomes. RESULTS: A total of 16 randomized controlled studies met the inclusion criteria for the systematic review and 9 were included in the meta-analyses. Theories were applied to the majority of the interventions. The most common behavior change techniques were "General information" and "Tracking/monitoring." Interventions with a duration of 2-6 months providing professional-led support with asynchronous and synchronous communication appeared to be associated with significant well-being outcomes. The pooled mean (95% confidence interval) difference between the intervention and control arms at follow-up on depression score was -0.31 (-0.73 to 0.11). The pooled mean difference on distress scores at follow-up was -0.11 (-0.38 to 0.16). No significant improvements in depression (P=.15) or distress (P=.43) were found following meta-analyses. CONCLUSIONS: While the meta-analyses demonstrated nonsignificant results for depression and distress scores, this review has shown that there is a potential for Web-based interventions to improve well-being outcomes in type 2 diabetes. Further research is required to confirm the findings of this review

    Nonexistence Certificates for Ovals in a Projective Plane of Order Ten

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    In 1983, a computer search was performed for ovals in a projective plane of order ten. The search was exhaustive and negative, implying that such ovals do not exist. However, no nonexistence certificates were produced by this search, and to the best of our knowledge the search has never been independently verified. In this paper, we rerun the search for ovals in a projective plane of order ten and produce a collection of nonexistence certificates that, when taken together, imply that such ovals do not exist. Our search program uses the cube-and-conquer paradigm from the field of satisfiability (SAT) checking, coupled with a programmatic SAT solver and the nauty symbolic computation library for removing symmetries from the search.Comment: Appears in the Proceedings of the 31st International Workshop on Combinatorial Algorithms (IWOCA 2020

    Systemic inflammatory response predicts outcome in patients undergoing resection for ductal adenocarcinoma head of pancreas

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    The aim of the present study was to examine the relationship between the clinicopathological status, the pre- and postoperative systemic inflammatory response and survival in patients undergoing potentially curative resection for ductal adenocarcinoma of the head of the pancreas. Patients (n=65) who underwent resection of ductal adenocarcinoma of the head of pancreas between 1993 and 2001, and had pre- and postoperative measurements of C-reactive protein, were included in the study. The majority of patients had stage III disease (International Union Against Cancer Criteria, IUCC), positive circumferential margin involvement (R1), tumour size greater than 25 mm with perineural and lymph node invasion and died within the follow-up period. On multivariate analysis, tumour size (hazard ratio (HR) 2.10, 95% confidence interval (CI) 1.20–3.68, P=0.009), vascular invasion (HR 2.58, 95% CI 1.48–4.50, P<0.001) and postoperative C-reactive protein (HR 2.00, 95% CI 1.14–3.52, P=0.015) retained independent significance. Those patients with a postoperative C-reactive protein ⩽10 mg l−1 had a median survival of 21.5 months compared with 8.4 months in those patients with a C-reactive protein >10 mg l−1 (P<0.001). The results of the present study indicate that, in patients who have undergone potentially curative resection for ductal adenocarcinoma of the head of pancreas, the presence of a systemic inflammatory response predicts poor outcome

    Rhinosinusitis derived Staphylococcal enterotoxin B possibly associates with pathogenesis of ulcerative colitis

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    BACKGROUND: During clinical practice, we noticed that some patients with both ulcerative colitis (UC) and chronic rhinosinusitis (CRS) showed amelioration of UC after treatment of CRS. This study was designed to identify a possible association between CRS and UC. METHODS: Thirty-two patients with both CRS and UC received treatment with functional endoscopic sinus surgery (FESS) for CRS. Clinical symptom scores for CRS and UC, as well as serum levels of anti-Staphylococcal enterotoxin B (SEB) were evaluated at week 0 and week 12. Sinus wash fluid SEB content was measured with enzyme-linked immunosorbent assay (ELISA). The surgically removed tissues were cultured to identify growth of Staphylococcus. aureus (S. aureus). Immunohistochemistry was employed to identify anti-SEB positive cells in the colonic mucosa. Colonic biopsies were obtained and incubated with SEB. Mast cell activation in the colonic mucosa in response to incubation with SEB was observed with electron microscopy and immunoassay. RESULTS: The clinical symptom scores of CRS and UC severe scores (UCSS) were significantly reduced in the UC-CRS patients after FESS. The number of cultured S. aureus colonies from the surgically removed sinus mucosa significantly correlated with the decrease in UCSS. High levels of SEB were detected in the sinus wash fluids of the patients with UC-CRS. Histamine and tryptase release was significantly higher in the culture supernate in the patients with UC-CRS than the patients with UC-only and normal controls. Anti-SEB positive cells were located in the colonic mucosa. CONCLUSION: The pathogenesis of UC in some patients may be associated with their pre-existing CRS by a mechanism of swallowing sinusitis-derived SEB. We speculate that SEB initiates inappropriate immune reactions and inflammation in the colonic mucosa that further progresses to UC

    Separable functions of wingless in distal and ventral patterning of the Tribolium leg

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    The gene wingless (wg) in Drosophila is an important factor in leg development. During embryonic development wg is involved in the allocation of the limb primordia. During imaginal disk development wg is involved in distal development and it has a separate role in ventral development. The expression pattern of wg is highly conserved in all arthropods (comprising data from insects, myriapods, crustaceans, and chelicerates), suggesting that its function in leg development is also conserved. However, recent work in other insects (e.g. the milkweed bug Oncopeltus fasciatus) argued against a role of wg in leg development. We have studied the role of wg in leg development of the flour beetle Tribolium castaneum. Using stage-specific staggered embryonic RNAi in wild-type and transgenic EGFP expressing enhancer trap lines we are able to demonstrate separable functions of Tribolium wg in distal and in ventral leg development. The distal role affects all podomeres distal to the coxa, whereas the ventral role is restricted to cells along the ventral midline of the legs. In addition, severe leg defects after injection into early embryonic stages are evidence that wg is also involved in proximal development and limb allocation in Tribolium. Our data suggest that the roles of wg in leg development are highly conserved in the holometabolous insects. Further studies will reveal the degree of conservation in other arthropod groups

    The Main Belt Comets and ice in the Solar System

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    We review the evidence for buried ice in the asteroid belt; specifically the questions around the so-called Main Belt Comets (MBCs). We summarise the evidence for water throughout the Solar System, and describe the various methods for detecting it, including remote sensing from ultraviolet to radio wavelengths. We review progress in the first decade of study of MBCs, including observations, modelling of ice survival, and discussion on their origins. We then look at which methods will likely be most effective for further progress, including the key challenge of direct detection of (escaping) water in these bodies

    Non-uniform recovery of left ventricular transmural mechanics in ST-segment elevation myocardial infarction

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    <p>Abstract</p> <p>Background</p> <p>After a transient ischemic episode, the subendocardial region is more severely injured than outer subepicardial layers and may regain a proportionately greater degree of mechanical function in the longitudinal direction. We sought to explore left ventricular (LV) transmural mechanics in patients with ST-segment elevation myocardial infarction (STEMI) for determining the mechanism underlying recovery of global LV function after primary percutaneous coronary intervention (PCI).</p> <p>Methods</p> <p>A total of 42 patients (62 ± 11 years old, 71% male) with a first STEMI underwent serial assessments of LV longitudinal, circumferential and radial strains (LS, CS and RS) by selective tracking of subendocardial and subepicardial regions within 48 hours and a median of 5 months after PCI. LV mechanical parameters were compared with sixteen age and gender matched normal controls.</p> <p>Results</p> <p>In comparison with controls, endocardial and epicardial LS were markedly attenuated at 48 hours following PCI (P < 0.001). An improvement in LV ejection fraction (EF > 5%) following PCI was seen in 24 (57%) patients and was associated with improvement in endocardial and epicardial LS (P < 0.001 and P = 0.003, respectively) and endocardial CS (P = 0.01). Radial strain and wall motion score index, however, remained persistently abnormal. The change in endocardial LS (OR 1.2, 95% CI 1.03 to 1.42, P = 0.01) and the change in epicardial LS (OR 1.2, 95% 1.03 to 1.46, P = 0.02) were significantly associated with the improvement in LVEF, independent of the location of STEMI and the presence of underlying multivessel disease.</p> <p>Conclusions</p> <p>In patients with STEMI treated by PCI, the recovery of LV subendocardial shortening strain seen in the longitudinal direction underlies the improvement in LV global function despite persistent abnormalities in radial mechanics and wall motion score index.</p
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