560 research outputs found

    Incorporation of calcium in glasses: a key to understand the vitrification of sewage sludge

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    The quantity of sewage sludge generated daily by wastewater treatment plants represents a major environmental problem and a financial burden for plant operators. Valorization strategies focusing on reusing sewage sludge as a raw material are currently developed. Vitrification can help us reduce the volume of waste and binds the components in the structure of chemically stable glasses and glass‐ceramics. In this study, the vitrification of sewage sludge inside a basaltic rock has been simulated by producing glasses and a glass‐ceramic from basalt enriched in calcium that lie between the stability fields of pyroxene and melilite in the system CaO‐MgO‐SiO2‐Al2O3. CaO addition causes the oxidation of the melt at above the liquidus, increases the crystallization temperature, decreases the melting temperature and improves the microhardness of the glasses Glass‐ceramic processes improves the properties of the Ca‐doped basalt glass. The microhardness of the glass (8.2 GPa) and the glass‐ceramic (8.6 GPa) and leaching tests (in the ppb range) place both the glass and the glass‐ceramics at the high end of the mechanical properties and chemical resistance of ceramic tiles for the building industry

    Selecting and implementing overview methods: implications from five exemplar overviews

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    This is the final version of the article. Available from BioMed Central via the DOI in this record.Background Overviews of systematic reviews are an increasingly popular method of evidence synthesis; there is a lack of clear guidance for completing overviews and a number of methodological challenges. At the UK Cochrane Symposium 2016, methodological challenges of five overviews were explored. Using data from these five overviews, practical implications to support methodological decision making of authors writing protocols for future overviews are proposed. Methods Methods, and their justification, from the five exemplar overviews were tabulated and compared with areas of debate identified within current literature. Key methodological challenges and implications for development of overview protocols were generated and synthesised into a list, discussed and refined until there was consensus. Results Methodological features of three Cochrane overviews, one overview of diagnostic test accuracy and one mixed methods overview have been summarised. Methods of selection of reviews and data extraction were similar. Either the AMSTAR or ROBIS tool was used to assess quality of included reviews. The GRADE approach was most commonly used to assess quality of evidence within the reviews. Eight key methodological challenges were identified from the exemplar overviews. There was good agreement between our findings and emerging areas of debate within a recent published synthesis. Implications for development of protocols for future overviews were identified. Conclusions Overviews are a relatively new methodological innovation, and there are currently substantial variations in the methodological approaches used within different overviews. There are considerable methodological challenges for which optimal solutions are not necessarily yet known. Lessons learnt from five exemplar overviews highlight a number of methodological decisions which may be beneficial to consider during the development of an overview protocol.The overview conducted by Pollock [19] was supported by a project grant from the Chief Scientist Office of the Scottish Government. The overview conducted by McClurg [21] was supported by a project grant by the Physiotherapy Research Foundation. The overview by Hunt [22] was supported as part of doctoral programme funding by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC). The overview conducted by Estcourt [20] was supported by an NIHR Cochrane Programme Grant for the Safe and Appropriate Use of Blood Components. The overview conducted by Brunton [23] was commissioned by the Department of Health as part of an ongoing programme of work on health policy research synthesis. Alex Pollock is employed by the Nursing, Midwifery and Allied Health Professions (NMAHP) Research Unit, which is supported by the Chief Scientist Office of the Scottish Government. Pauline Campbell is supported by the Chief Nurses Office of the Scottish Government

    Human bite injuries in the oro-facial region at the Muhimbili National Hospital, Tanzania

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    <p>Abstract</p> <p>Background</p> <p>Human bites in the maxillofacial region compromise function and aesthetics, resulting in social and psychological effects. There is paucity of information regarding human bite injuries in Tanzania. The aim of the study was to assess the occurrence, treatment modalities and prognosis of human bite injuries in the oro-facial region at the Muhimbili National Hospital Dar es Salaam, Tanzania.</p> <p>Methods</p> <p>In a prospective study the details of patients with human bite injuries in the oro-facial region who attended at the Department of Oral and Maxillofacial Surgery of the Muhimbili National Hospital between January 2001 and December 2005 were recorded. Data included information on age, sex, site, duration of the injury at the time of reporting to hospital, reasons, details of treatment offered and outcome after treatment.</p> <p>Results</p> <p>A total of 33 patients, 13 males and 20 females aged between 12 and 49 years with human bite injuries in the oro-facial region were treated. Thirty patients presented with clean uninfected wounds while 3 had infected wounds. The most (45.5%) frequently affected site was the lower lip. Treatment offered included thorough surgical cleansing with adequate surgical debridement and primary suturing. Tetanus prophylaxis and a course of broad-spectrum antibiotics were given to all the patients. In 90% of the 30 patients who were treated by suturing, the healing was uneventful with only 10% experiencing wound infection or necrosis. Three patients who presented with wounds that had signs of infection were treated by surgical cleansing with debridement, antibiotics and daily dressing followed by delayed primary suturing.</p> <p>Conclusion</p> <p>Most of the human bite injuries in the oro-facial region were due to social conflicts. Although generally considered to be dirty or contaminated they could be successfully treated by surgical cleansing and primary suture with a favourable outcome. Management of such injuries often need multidisciplinary approach.</p

    Cellular Islet Autoimmunity Associates with Clinical Outcome of Islet Cell Transplantation

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    Islet cell transplantation can cure type 1 diabetes (T1D), but only a minority of recipients remains insulin-independent in the following years. We tested the hypothesis that allograft rejection and recurrent autoimmunity contribute to this progressive loss of islet allograft function.Twenty-one T1D patients received cultured islet cell grafts prepared from multiple donors and transplanted under anti-thymocyte globulin (ATG) induction and tacrolimus plus mycophenolate mofetil (MMF) maintenance immunosuppression. Immunity against auto- and alloantigens was measured before and during one year after transplantation. Cellular auto- and alloreactivity was assessed by lymphocyte stimulation tests against autoantigens and cytotoxic T lymphocyte precursor assays, respectively. Humoral reactivity was measured by auto- and alloantibodies. Clinical outcome parameters--including time until insulin independence, insulin independence at one year, and C-peptide levels over one year--remained blinded until their correlation with immunological parameters. All patients showed significant improvement of metabolic control and 13 out of 21 became insulin-independent. Multivariate analyses showed that presence of cellular autoimmunity before and after transplantation is associated with delayed insulin-independence (p = 0.001 and p = 0.01, respectively) and lower circulating C-peptide levels during the first year after transplantation (p = 0.002 and p = 0.02, respectively). Seven out of eight patients without pre-existent T-cell autoreactivity became insulin-independent, versus none of the four patients reactive to both islet autoantigens GAD and IA-2 before transplantation. Autoantibody levels and cellular alloreactivity had no significant association with outcome.In this cohort study, cellular islet-specific autoimmunity associates with clinical outcome of islet cell transplantation under ATG-tacrolimus-MMF immunosuppression. Tailored immunotherapy targeting cellular islet autoreactivity may be required. Monitoring cellular immune reactivity can be useful to identify factors influencing graft survival and to assess efficacy of immunosuppression.Clinicaltrials.gov NCT00623610

    The extramural metastasis might be categorized in lymph node staging for colorectal cancer

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    <p>Abstract</p> <p>Background</p> <p>The objective of this study is to assess the clinical significance and prognostic impact of extramural metastasis in colorectal carcinoma and establish an optimal categorization in the staging system.</p> <p>Methods</p> <p>To determine the frequency and prognostic significance of extramural metastasis, from 2000 to 2005, a total of 1,215 patients with colorectal cancer who underwent surgical resection were recruited into this study. Individual demographic and clinicopathologic data were collected including tumor stage, nodal stage, tumor histology, degree of tumor differentiation, and presence of lymphovascular invasion. After surgery, all patients received standard treatments and follow-up, which were closed in April 2010.</p> <p>Results</p> <p>EM was detected in 167 (13.7%) patients and in 230 (1.8%) of the 12,534 nodules retrieved as 'lymph nodes'. The incidence of extramural metastasis was significantly higher in patients with large tumors, deeper invasive depth and more lymph node metastasis (P < 0.001). After curative operation, overall survival was significantly worse for patients with extramural metastasis than those without (P < 0.001). Multivariate analysis identified extramural metastasis as an independent prognostic factor (RR = 2.1, 95%CI:1.5-3.0). By using the Akaike information criterion (AIC), N staging was capable of predicting survival outcome with the highest accuracy when both nodal involvement and extramural metastasis were treated together as N factors(AIC = 1025.3).</p> <p>Conclusion</p> <p>Extramural metastasis might be diagnosed as replaced lymph nodes in the process of classification, thus forming a new categorization.</p

    Detection of the A189G mtDNA heteroplasmic mutation in relation to age in modern and ancient bones.

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    International audienceThe aim of this study was to demonstrate the presence of the A189G age-related point mutation on DNA extracted from bone. For this, a peptide nucleic acid (PNA)/DNA sequencing method which can determine an age threshold for the appearance of the mutation was used. Initially, work was done in muscle tissue in order to evaluate the sensitivity of the technique and afterwards in bone samples from the same individuals. This method was also applied to ancient bones from six well-preserved skeletal remains. The mutation was invariably found in muscle, and at a rate of up to 20% in individuals over 60 years old. In modern bones, the mutation was detected in individuals aged 38 years old or more, at a rate of up to 1%, but its occurrence was not systematic (only four out of ten of the individuals over 50 years old carried the heteroplasmy). For ancient bones, the mutation was also found in the oldest individuals according to osteologic markers. The study of this type of age-related mutation and a more complete understanding of its manifestation has potentially useful applications. Combined with traditional age markers, it could improve identification accuracy in forensic cases or in anthropological studies of ancient populations

    Congenital bovine spinal dysmyelination is caused by a missense mutation in the SPAST gene

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    Bovine spinal dysmyelination (BSD) is a recessive congenital neurodegenerative disease in cattle (Bos taurus) characterized by pathological changes of the myelin sheaths in the spinal cord. The occurrence of BSD is a longstanding problem in the American Brown Swiss (ABS) breed and in several European cattle breeds upgraded with ABS. Here, we show that the disease locus on bovine chromosome 11 harbors the SPAST gene that, when mutated, is responsible for the human disorder hereditary spastic paraplegia (HSP). Initially, SPAST encoding Spastin was considered a less likely candidate gene for BSD since the modes of inheritance as well as the time of onset and severity of symptoms differ widely between HSP and BSD. However, sequence analysis of the bovine SPAST gene in affected animals identified a R560Q substitution at a position in the ATPase domain of the Spastin protein that is invariant from insects to mammals. Interestingly, three different mutations in human SPAST gene at the equivalent position are known to cause HSP. To explore this observation further, we genotyped more than 3,100 animals of various cattle breeds and found that the glutamine allele exclusively occurred in breeds upgraded with ABS. Furthermore, all confirmed BSD carriers were heterozygous, while all affected calves were homozygous for the glutamine allele consistent with recessive transmission of the underlying mutation and complete penetrance in the homozygous state. Subsequent analysis of recombinant Spastin in vitro showed that the R560Q substitution severely impaired the ATPase activity, demonstrating a causal relationship between the SPAST mutation and BSD

    Secondary insults following traumatic brain injury enhance complement activation in the human brain and release of the tissue damage marker S100B

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    To access publisher full text version of this article. Please click on the hyperlink in Additional Links field.OBJECT: Complement activation has been suggested to play a role in the development of secondary injuries following traumatic brain injury (TBI). The present study was initiated in order to analyze complement activation in relation to the primary brain injury and to secondary insults, frequently occurring following TBI. METHODS: Twenty patients suffering from severe TBI (Glasgow coma score ≀ 8) were included in the study. The "membrane attack complex," C5b9, which is the cytolytic end product of the complement system was analyzed in cerebrospinal fluid (CSF). The degree of brain tissue damage was assessed using the release of S100B and neuron-specific enolase (NSE) to the CSF and blood. The blood-brain barrier was assessed using the CSF/serum quotient of albumin (Q (A)). RESULTS: Following impact, initial peaks (0-48 h) of C5b9, S100B, and NSE with a concomitant loss of integrity of the blood-brain barrier were observed. Secondary insults at the intensive care unit were monitored. Severe secondary insults were paralleled by a more pronounced complement activation (C5b9 in CSF) as well as increased levels of S100B (measured in CSF), but not with NSE. CONCLUSION: This human study indicates that complement activation in the brain is triggered not only by the impact of trauma per se but also by the amount of secondary insults that frequently occur at the scene of accident as well as during treatment in the neurointensive care unit. Complement activation and in particular the end product C5b9 may in turn contribute to additional secondary brain injuries by its membrane destructive properties

    Beauty photoproduction measured using decays into muons in dijet events in ep collisions at s\sqrt{s}=318 GeV

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    The photoproduction of beauty quarks in events with two jets and a muon has been measured with the ZEUS detector at HERA using an integrated luminosity of 110 pb−1^{- 1}. The fraction of jets containing b quarks was extracted from the transverse momentum distribution of the muon relative to the closest jet. Differential cross sections for beauty production as a function of the transverse momentum and pseudorapidity of the muon, of the associated jet and of xγjetsx_{\gamma}^{jets}, the fraction of the photon's momentum participating in the hard process, are compared with MC models and QCD predictions made at next-to-leading order. The latter give a good description of the data.Comment: 32 pages, 6 tables, 7 figures Table 6 and Figure 7 revised September 200
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