1,626 research outputs found

    The epiphyseal tubercle in adolescent hips

    Get PDF
    Background It has already been shown in animals and using anatomical human specimens that chronic slippage of the adolescent upper (capital) femoral epiphysis is unlikely to take place by shearing due to the presence of an epiphyseal tubercle projecting down into the metaphysis

    A population-based study of 92 clinically recognised risk factors for heart failure: co-occurrence, prognosis and preventive potential

    Get PDF
    BACKGROUND: Primary prevention strategies for heart failure(HF) have had limited success, possibly due to a wide range of underlying risk factors(RFs). Systematic evaluations of the prognostic burden and preventive potential across this wide range of risk factors are lacking. OBJECTIVE: To estimate evidence, prevalence and co-occurrence for primary prevention and impact on prognosis of RFs for incident HF. METHODS: We systematically reviewed trials and observational evidence of primary HF prevention across 92 putative aetiologic RFs for HF identified from US and European clinical practice guidelines. We identified 170 885 individuals aged ≥30 years with incident HF from 1997-2017, using linked primary and secondary care UK electronic health records(EHR) and rule-based phenotypes(ICD-10, Read Version 2, OPCS-4 procedure and medication codes) for each of 92 RFs. RESULTS: Only 10/92 factors had high quality observational evidence for association with incident HF; 7 had effective RCT-based interventions for HF prevention(RCT-HF), and 6 for CVD prevention, but not HF(RCT-CVD), and the remainder had no RCT-based preventive interventions(RCT-0). We were able to map 91/92 risk factors to EHR using 5961 terms, and 88/91 factors were represented by at least one patient. In the 5 years prior to HF diagnosis, 44.3% had ≥4 RFs. By RCT evidence, the most common RCT-HF RFs were hypertension(48.5%), stable angina(34.9%), unstable angina(16.8%), myocardial infarction(15.8%), and diabetes(15.1%); RCT-CVD RFs were smoking(46.4%) and obesity(29.9%); and RCT-0 RFs were atrial arrhythmias(17.2%), cancer(16.5%),), heavy alcohol intake(14.9%). Mortality at 1 year varied across all 91 factors(lowest: pregnancy-related hormonal disorder 4.2%; highest: phaeochromocytoma 73.7%). Among new HF cases, 28.5% had no RCT-HF RFs and 38.6% had no RCT-CVD RFs. 15.6% had either no RF or only RCT-0 RFs. CONCLUSION: 1 in 6 individuals with HF have no recorded RFs or RFs without trials. We provide a systematic map of primary preventive opportunities across a wide range of RFs for HF, demonstrating a high burden of co-occurrence and the need for trials tackling multiple RFs

    3D time series analysis of cell shape using Laplacian approaches

    Get PDF
    Background: Fundamental cellular processes such as cell movement, division or food uptake critically depend on cells being able to change shape. Fast acquisition of three-dimensional image time series has now become possible, but we lack efficient tools for analysing shape deformations in order to understand the real three-dimensional nature of shape changes. Results: We present a framework for 3D+time cell shape analysis. The main contribution is three-fold: First, we develop a fast, automatic random walker method for cell segmentation. Second, a novel topology fixing method is proposed to fix segmented binary volumes without spherical topology. Third, we show that algorithms used for each individual step of the analysis pipeline (cell segmentation, topology fixing, spherical parameterization, and shape representation) are closely related to the Laplacian operator. The framework is applied to the shape analysis of neutrophil cells. Conclusions: The method we propose for cell segmentation is faster than the traditional random walker method or the level set method, and performs better on 3D time-series of neutrophil cells, which are comparatively noisy as stacks have to be acquired fast enough to account for cell motion. Our method for topology fixing outperforms the tools provided by SPHARM-MAT and SPHARM-PDM in terms of their successful fixing rates. The different tasks in the presented pipeline for 3D+time shape analysis of cells can be solved using Laplacian approaches, opening the possibility of eventually combining individual steps in order to speed up computations

    Significance of Metastatic Lymph Node Ratio on Stimulated Thyroglobulin Levels in Papillary Thyroid Carcinoma after Prophylactic Unilateral Central Neck Dissection

    Get PDF
    Background: Prognostic significance of metastatic central lymph node ratio (CLNR) in papillary thyroid carcinoma (PTC) remains unknown. Because postsurgical detectable stimulated thyroglobulin (DsTg) after radioiodine ablation may imply persistent or recurrent disease, we evaluated the association between CLNR and rate of DsTg in patients with PTC who underwent unilateral prophylactic central neck dissection. Methods: To be eligible for analysis, the prophylactic central neck dissection specimen had to contain ≥3 central lymph nodes (CLNs) with ≥1 harboring metastasis. Of 129 specimens, 51 (39.5%) were eligible. CLNR was calculated as follows: (number of metastatic CLNs/number of CLNs retrieved) × 100. They were categorized into group 1 (CLNR 66.67%) (n = 22). Postablation sTg level was measured 6 months after radioiodine ablation. A multivariate analysis was conducted to identify factors for postablation DsTg. Results: Young age, palpable neck swelling, large tumor size, advanced tumor, node, metastasis system (TNM) stage, and large number of metastatic CLNs were significantly associated with high CLNR (Ppublished_or_final_versionSpringer Open Choice, 21 Feb 201

    Seroprevalence of hepatitis B and C viral co-infections among children infected with human immunodeficiency virus attending the paediatric HIV care and treatment center at Muhimbili National Hospital in Dar-es-Salaam, Tanzania

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>With increased availability of antibiotics and antifungal agents hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are becoming a cause for significant concern in HIV infected children. We determined the seroprevalence and risk factors for HBV and HCV among HIV infected children aged 18 months to 17 years, attending the Paediatric HIV Care and Treatment Center (CTC) at Muhimbili National Hospital (MNH) in Dar-es-Salaam, Tanzania.</p> <p>Methods</p> <p>Investigations included; interviews, physical examination and serology for HBsAg, IgG antibodies to HCV and alanine aminotransferase (ALT) levels. HIV serostatus and CD4 counts were obtained from patient records.</p> <p>Results</p> <p>167 HIV infected children, 88(52.7%) males and 79(47.3%) females were enrolled. The overall prevalence of hepatitis co-infection was 15%, with the seroprevalence of HBV and HCV being 1.2% and 13.8%, respectively. Hepatitis virus co-infection was not associated with any of the investigated risk factors and there was no association between HBV and HCV. Elevated ALT was associated with hepatitis viral co-infection but not with ART usage or immune status.</p> <p>Conclusion</p> <p>The high seroprevalence (15%) of hepatitis co-infection in HIV infected children attending the Paediatrics HIV CTC at the MNH calls for routine screening of hepatitis viral co-infection and modification in the management of HIV infected children.</p

    Macrophage-derived human resistin is induced in multiple helminth infections and promotes inflammatory monocytes and increased parasite burden.

    Get PDF
    Parasitic helminth infections can be associated with lifelong morbidity such as immune-mediated organ failure. A better understanding of the host immune response to helminths could provide new avenues to promote parasite clearance and/or alleviate infection-associated morbidity. Murine resistin-like molecules (RELM) exhibit pleiotropic functions following helminth infection including modulating the host immune response; however, the relevance of human RELM proteins in helminth infection is unknown. To examine the function of human resistin (hResistin), we utilized transgenic mice expressing the human resistin gene (hRetnTg+). Following infection with the helminth Nippostrongylus brasiliensis (Nb), hResistin expression was significantly upregulated in infected tissue. Compared to control hRetnTg- mice, hRetnTg+ mice suffered from exacerbated Nb-induced inflammation characterized by weight loss and increased infiltration of inflammatory monocytes in the lung, along with elevated Nb egg burdens and delayed parasite expulsion. Genome-wide transcriptional profiling of the infected tissue revealed that hResistin promoted expression of proinflammatory cytokines and genes downstream of toll-like receptor signaling. Moreover, hResistin preferentially bound lung monocytes, and exogenous treatment of mice with recombinant hResistin promoted monocyte recruitment and proinflammatory cytokine expression. In human studies, increased serum resistin was associated with higher parasite load in individuals infected with soil-transmitted helminths or filarial nematode Wuchereria bancrofti, and was positively correlated with proinflammatory cytokines. Together, these studies identify human resistin as a detrimental factor induced by multiple helminth infections, where it promotes proinflammatory cytokines and impedes parasite clearance. Targeting the resistin/proinflammatory cytokine immune axis may provide new diagnostic or treatment strategies for helminth infection and associated immune-mediated pathology

    Escaping the Ashby limit for mechanical damping/stiffness trade-off using a constrained high internal friction interfacial layer.

    Get PDF
    The development of new materials with reduced noise and vibration levels is an active area of research due to concerns in various aspects of environmental noise pollution and its effects on health. Excessive vibrations also reduce the service live of the structures and limit the fields of their utilization. In oscillations, the viscoelastic moduli of a material are complex and it is their loss part - the product of the stiffness part and loss tangent - that is commonly viewed as a figure of merit in noise and vibration damping applications. The stiffness modulus and loss tangent are usually mutually exclusive properties so it is a technological challenge to develop materials that simultaneously combine high stiffness and high loss. Here we achieve this rare balance of properties by filling a solid polymer matrix with rigid inorganic spheres coated by a sub-micron layer of a viscoelastic material with a high level of internal friction. We demonstrate that this combination can be experimentally realised and that the analytically predicted behaviour is closely reproduced, thereby escaping the often termed 'Ashby' limit for mechanical stiffness/damping trade-off and offering a new route for manufacturing advanced composite structures with markedly reduced noise and vibration levels

    Fine-mapping of genetic loci driving spontaneous clearance of hepatitis C virus infection

    Get PDF
    Approximately three quarters of acute hepatitis C (HCV) infections evolve to a chronic state, while one quarter are spontaneously cleared. Genetic predispositions strongly contribute to the development of chronicity. We have conducted a genome-wide association study to identify genomic variants underlying HCV spontaneous clearance using ImmunoChip in European and African ancestries. We confrmed two previously reported signifcant associations, in the IL28B/IFNL4 and the major histocompatibility complex (MHC) regions, with spontaneous clearance in the European population. We further fne-mapped the association in the MHC to a region of about 50 kilo base pairs, down from 1 mega base pairs in the previous study. Additional analyses suggested that the association in MHC is stronger in samples from North America than those from Europe
    corecore