42 research outputs found

    Mitigation of petroleum-hydrocarbon-contaminated hazardous soils using organic amendments:A review

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    The term “Total petroleum hydrocarbons” (TPH) is used to describe a complex mixture of petroleum-based hydrocarbons primarily derived from crude oil. Those compounds are considered as persistent organic pollutants in the terrestrial environment. A wide array of organic amendments is increasingly used for the remediation of TPH-contaminated soils. Organic amendments not only supply a source of carbon and nutrients but also add exogenous beneficial microorganisms to enhance the TPH degradation rate, thereby improving the soil health. Two fundamental approaches can be contemplated within the context of remediation of TPH-contaminated soils using organic amendments: (i) enhanced TPH sorption to the exogenous organic matter (immobilization) as it reduces the bioavailability of the contaminants, and (ii) increasing the solubility of the contaminants by supplying desorbing agents (mobilization) for enhancing the subsequent biodegradation. Net immobilization and mobilization of TPH have both been observed following the application of organic amendments to contaminated soils. This review examines the mechanisms for the enhanced remediation of TPH-contaminated soils by organic amendments and discusses the influencing factors in relation to sequestration, bioavailability, and subsequent biodegradation of TPH in soils. The uncertainty of mechanisms for various organic amendments in TPH remediation processes remains a critical area of future research. © 2021 Elsevier B.V

    The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

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    Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

    Strategies for improving the efficacy and therapeutic ratio of glucocorticoids

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    Although glucocorticoids are very effective in suppressing inflammation there is a clear clinical unmet need for new or improved glucocorticoids in patients with severe asthma and COPD. Recent developments include the targeted deposition of ultrafine glucocorticoid particles to treat small airways and the potential of novel agents that have a reduced side effect profile. Understanding the drivers of relative glucocorticoid resistance in these patients may lead to the development of newer drugs aimed at subsets of patients, for example asthmatics with high periostin levels. Alternatively, inhibitors of kinase pathways that are associated with inflammatory responses may be able to modulate glucocorticoid function and combinations of these inhibitors along with novel glucocorticoids may provide the combination therapy of the future

    A role for phosphoinositol 3-kinase delta in the impairment of glucocorticoid responsiveness in patients with chronic obstructive pulmonary disease.

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    BACKGROUND: Glucocorticoid function is markedly impaired in the lungs of patients with chronic obstructive pulmonary disease (COPD). This reduction in glucocorticoid sensitivity might be due to an oxidant-mediated increase in phosphoinositol 3-kinase (PI3K) delta signaling. OBJECTIVE: We sought to determine the role of PI3Kdelta in the reduced glucocorticoid responsiveness in patients with COPD. METHODS: Peripheral lung tissue was obtained from 24 patients with COPD, 20 age-matched smokers with normal lung function, and 13 nonsmokers. Peripheral blood monocytes were isolated from 9 patients with COPD and 7 age-matched smokers with normal lung function and from healthy volunteers. RESULTS: The expressions of PI3Kdelta and Akt phosphorylation were increased in macrophages from patients with COPD compared with those from control groups of age-matched smokers and nonsmokers. In vitro oxidative stress induced phosphorylation of Akt in monocytes and macrophages, which was abolished by means of selective inhibition of PI3Kdelta but not PI3Kgamma. Dexamethasone was less effective at repressing LPS-induced GM-CSF and CXC motif chemokine 8 release in blood monocytes from patients with COPD compared with age-matched smokers. This reduced sensitivity was reversed by inhibition of PI3Kdelta but not PI3Kgamma. CONCLUSION: PI3Kdelta expression and signaling is increased in the lungs of patients with COPD. Selective inhibition of PI3Kdelta might restore glucocorticoid function in patients with COPD and might therefore present a potential therapeutic target. Copyright 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved

    Coma scales for children with severe falciparum malaria

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    The Blantyre coma scale (BCS) is used to assess children with severe falciparum malaria, particularly as a criterion for cerebral malaria, but it has not been formally validated. We compared the BCS to the Adelaide coma scale (ACS), for Kenyan children with severe malaria. We examined the inter-observer agreement between 3 observers in the assessment of coma scales on 17 children by measuring the proportion of agreement (PA), disagreement rate (DR) and fixed sample size Îş (Îşn). We assessed the sensivitity and specificity of the scales in detecting events (seizures and hypoglycaemia) in 240 children during admission and the usefulness of the scales in predicting outcome. There was considerable disagreement between observers in the assessment of both scales (BCS: PA = 0.55, DR = 0.09 and Îşn = 0.27; ACS: PA = O.36, DR = O.31, and Îşn = 0.31), particularly with the verbal component of the BCS (Îşn = 0.02). Compared to the ACS, the BCS was more specific (0.85 for BCS and 0.80 for ACS), but less sensitive (0.25-0.69 vs. 0.38-0.88 respectively) in detecting events and was a worse predictor of neurological sequelae. The BCS provided a better overall assessment of a child's incapacity from falciparum malaria, but the ACS was more useful in assessing neurological disturbances.</p

    Chemokines and chemokine receptors blockers as new drugs for the treatment of chronic obstructive pulmonary disease

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    Chronic obstructive pulmonary disease (COPD) is characterised by an abnormal inflammatory response of the lung to noxious particles or gases. The cellular inflammatory response in COPD is characterised by an increased number of inflammatory cells in the lungs. Although the molecular and cellular mechanisms responsible for the development of COPD are not well understood; several mediators are assumed to regulate the activation and recruitment of these inflammatory cells into the lung of COPD patients particularly those belonging to the chemokine family. Inhibitors or blockers of chemokine and chemokine receptors are therefore of great interest as potential novel therapies for COPD and many are now in clinical development. A high degree of redundancy exists in the chemokine network and inhibition of a single chemokine or receptor may not be sufficient to block the inflammatory response. Despite this, animal studies suggest a strong rationale for inhibiting the chemokine network in COPD. As such, every leading pharmaceutical company maintains a significant interest in developing agents that regulate leukocyte navigation as potential anti-inflammatory drugs. Drugs and antibodies targeting chemokines and their receptors are generally still in early stages of development and the results of clinical trial are awaited with great interest. These agents may not only provide improved management of COPD but also, importantly, indicate proof-of-concept to further clarify the role of chemokines in the pathophysiology of COPD

    A uniaxial tensile stage with tracking capabilities for micro X-ray diffraction applications

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    First results are presented for a uniaxial tensile stage designed to operate on a scanning micro X-ray diffraction synchrotron beamline. The new tensile stage allows experiments at typical loading cycles used in standard engineering stress&ndash;strain tests. Several key features have been implemented to support in situ loading experiments at the intragranular length scale. The physical size and weight of the load cell were minimized to maintain the correct working distance for the X-ray focusing optics and to avoid overloading the high-resolution raster scan translation stages. A high-magnification optical microscope and image correlation code were implemented to enable automated online tracking capabilities during macroscopic elongation of the sample. Preliminary in situ tensile loading experiments conducted on beamline 12.3.2 at the Advanced Light Source using a polycrystalline commercial-purity Ti test piece showed that the elastic&ndash;plastic response of individual grains could be measured with submicrometre spatial resolution. The experiments highlight the unique instrumentation capabilities of the tensile stage for direct measurement of deviatoric strain and observation of dislocation patterning on an intragranular length scale as a function of applied load

    Surveillance of cancer risks for firefighters, police, and armed forces among men in a Canadian census cohort

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    Background: Firefighters, police, and armed services may be exposed to hazards such as combustion by-products and shift work. Methods: The CanCHEC cohort linked 1991 census data to the Canadian cancer registry for follow up. Cox proportional hazards modeling was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) to estimate risks for firefighter, police, or armed forces compared to workers in other occupations. Results: The cohort of 1 108 410 men included 4535 firefighters, 10 055 police, and 9165 armed forces. For firefighters, elevated risks were noted for Hodgkin's lymphoma (HR: 2.89, 95%CI: 1.29-6.46), melanoma (HR: 1.67, 95%CI: 1.17-2.37), and prostate cancer (HR: 1.18, 95%CI: 1.01-1.37). Police had elevated risks for melanoma (HR:1.69, 95%CI: 1.32-2.16) and prostate cancer (HR:1.28, 95%CI: 1.14-1.42). No significant associations were found for armed forces workers. Conclusions: Canadian firefighters, police, and armed services, may be at an increased risk of developing certain cancers. Results suggested that a healthy worker effect may influence risk estimates
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