501 research outputs found

    Cross leg flaps: are they relevant in the present era?

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    Background: Injuries of lower limb due to road traffic accidents are challenging to reconstruct due to paucity of tissues and damage to vasculature. Recurrent trophic ulcers are also difficult to reconstruct due to stigmata of previous surgeries. When local and regional flaps are not available, free flaps become the best option. The success of free flap depends on the presence of healthy recipient vessels and microsurgical expertise. In cases where the free flaps have failed or when there is no available soft tissue for local flaps, cross leg flaps are a method of resurfacing and salvaging the limb.Methods: This Study was done from January 2013 to January 2016 in Rajiv Gandhi Government General Hospital, Chennai. 20 patients were included in the study and the flaps used were conventional cross leg and cross leg reverse superficial sural artery flap.Results: All flaps survived. There was one case of wound dehiscence managed by re-insetting, two cases with marginal necrosis which were managed conservatively. One case of partial loss which was managed by STSG and one case of sinus formation due to tuberculosis managed with ATT. Remaining flaps had no complications.Conclusions: Cross leg flaps are still relevant in the present era of microsurgery. They can be the primary choice of reconstruction or as a workhorse when free flaps have failed or other loco regional flaps are already exhausted. Immobilisation and two stage reconstruction are few disadvantages which when weighed against limb salvage are acceptable.

    Automation of environmental ELISAs

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    ELISAs for pesticides and herbicides in environmental and agricultural samples are becoming very important in screening applications [1-3]. Traditional chromatographic methods are expensive and results need long turnaround times, making them incompatible with rapid on-site decision making. ELISA methods have been shown to meet or exceed the performance of gas chromatography—they offer rapid low-cost analysis, thereby increasing the frequency of sampling and enhancing data quality. Automated ELISA workstations allow the full benefit of these kits to be realized. Sample preparation, reagent pipetting, incubation, and photometric evaluation can be performed without user intervention. Reliability is increased through the elimination of operator error, better accuracy and precision, and often higher speed. Much larger batch sizes are possible and these systems can provide sample tracking with report generation for documentation requirements. In this paper the manual procedures and ELISA methods are compared and some critical aspects of automating these ELISA kits are discussed

    Characterization of aerosol hygroscopicity over the Northeast Pacific Ocean: Impacts on prediction of CCN and stratocumulus cloud droplet number concentrations

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    During the Marine Aerosol Cloud and Wildfire Study (MACAWS) in June and July of 2018, aerosol composition and cloud condensation nuclei (CCN) properties were measured over the N.E. Pacific to characterize the influence of aerosol hygroscopicity on predictions of ambient CCN and stratocumulus cloud droplet number concentrations (CDNC). Three vertical regions were characterized, corresponding to the marine boundary layer (MBL), an above‐cloud organic aerosol layer (AC‐OAL), and the free troposphere (FT) above the AC‐OAL. The aerosol hygroscopicity parameter (κ) was calculated from CCN measurements (κ_(CCN)) and bulk aerosol mass spectrometer (AMS) measurements (κ_(AMS)). Within the MBL, measured hygroscopicities varied between values typical of both continental environments (~0.2) and remote marine locations (~0.7). For most flights, CCN closure was achieved within 20% in the MBL. For five of the seven flights, assuming a constant aerosol size distribution produced similar or better CCN closure than assuming a constant “marine” hygroscopicity (κ = 0.72). An aerosol‐cloud parcel model was used to characterize the sensitivity of predicted stratocumulus CDNC to aerosol hygroscopicity, size distribution properties, and updraft velocity. Average CDNC sensitivity to accumulation mode aerosol hygroscopicity is 39% as large as the sensitivity to the geometric median diameter in this environment. Simulations suggest CDNC sensitivity to hygroscopicity is largest in marine stratocumulus with low updraft velocities (0.6 m s⁻¹), where hygroscopic properties of the Aitken mode dominate hygroscopicity sensitivity

    Characterization of aerosol hygroscopicity over the Northeast Pacific Ocean: Impacts on prediction of CCN and stratocumulus cloud droplet number concentrations

    Get PDF
    During the Marine Aerosol Cloud and Wildfire Study (MACAWS) in June and July of 2018, aerosol composition and cloud condensation nuclei (CCN) properties were measured over the N.E. Pacific to characterize the influence of aerosol hygroscopicity on predictions of ambient CCN and stratocumulus cloud droplet number concentrations (CDNC). Three vertical regions were characterized, corresponding to the marine boundary layer (MBL), an above‐cloud organic aerosol layer (AC‐OAL), and the free troposphere (FT) above the AC‐OAL. The aerosol hygroscopicity parameter (κ) was calculated from CCN measurements (κ_(CCN)) and bulk aerosol mass spectrometer (AMS) measurements (κ_(AMS)). Within the MBL, measured hygroscopicities varied between values typical of both continental environments (~0.2) and remote marine locations (~0.7). For most flights, CCN closure was achieved within 20% in the MBL. For five of the seven flights, assuming a constant aerosol size distribution produced similar or better CCN closure than assuming a constant “marine” hygroscopicity (κ = 0.72). An aerosol‐cloud parcel model was used to characterize the sensitivity of predicted stratocumulus CDNC to aerosol hygroscopicity, size distribution properties, and updraft velocity. Average CDNC sensitivity to accumulation mode aerosol hygroscopicity is 39% as large as the sensitivity to the geometric median diameter in this environment. Simulations suggest CDNC sensitivity to hygroscopicity is largest in marine stratocumulus with low updraft velocities (0.6 m s⁻¹), where hygroscopic properties of the Aitken mode dominate hygroscopicity sensitivity

    PTPRF is disrupted in a patient with syndromic amastia

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    <p>Abstract</p> <p>Background</p> <p>The presence of mammary glands distinguishes mammals from other organisms. Despite significant advances in defining the signaling pathways responsible for mammary gland development in mice, our understanding of human mammary gland development remains rudimentary. Here, we identified a woman with bilateral amastia, ectodermal dysplasia and unilateral renal agenesis. She was found to have a chromosomal balanced translocation, 46,XX,t(1;20)(p34.1;q13.13). In addition to characterization of her clinical and cytogenetic features, we successfully identified the interrupted gene and studied its consequences.</p> <p>Methods</p> <p>Characterization of the breakpoints was performed by molecular cytogenetic techniques. The interrupted gene was further analyzed using quantitative real-time PCR and western blotting. Mutation analysis and high-density SNP array were carried out in order to find a pathogenic mutation. Allele segregations were obtained by haplotype analysis.</p> <p>Results</p> <p>We enabled to identify its breakpoint on chromosome 1 interrupting the <it>protein tyrosine receptor type F gene </it>(<it>PTPRF</it>). While the patient's mother and sisters also harbored the translocated chromosome, their non-translocated chromosomes 1 were different from that of the patient. Although a definite pathogenic mutation on the paternal allele could not be identified, <it>PTPRF</it>'s RNA and protein of the patient were significantly less than those of her unaffected family members.</p> <p>Conclusions</p> <p>Although <it>ptprf </it>has been shown to involve in murine mammary gland development, no evidence has incorporated <it>PTPRF </it>in human organ development. We, for the first time, demonstrated the possible association of <it>PTPRF </it>with syndromic amastia, making it a prime candidate to investigate for its spatial and temporal roles in human breast development.</p

    The impact of changes in stakeholder salience on CSR activities in Russian energy firms: a contribution to the divergence / convergence debate

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    This empirical paper examines the drivers underpinning changes to socially-responsible behaviours in the Russian energy sector. Responding to recent requests to contextualise CSR research, we focus on the changing set of stakeholders and developments in their saliency as reflected in corporations’ CSR activities. Based on interviews with more than thirty industry professionals, our findings suggest that Russian energy companies’ CSR is strongly stakeholder driven, and organisations adapt their activities according to their dependence on the resources that these salient stakeholders possess. We challenge the proposition that CSR in Russia arises from purely endogenous, historical, paternalism or neo-paternalism. We identify stakeholders that now shape CSR in the Russian energy sector, both endogenous (institutional and contextual forces relevant to the national business system) and exogenous (relating to the organisational field of the energy industry - international by nature). We thereby contribute to the convergence / divergence debate within CSR theory by demonstrating that both national business systems and the organisational field must be taken into account when analysing the forces that shape CSR strategies in any one country

    Antibiotic prescribing for upper respiratory infections among children in rural China: a cross-sectional study of outpatient prescriptions

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    Background: Overuse of antibiotics contributes to the development of antimicrobial resistance. Objective: This study aims to assess the condition of antibiotic use at health facilities at county, township and village levels in rural Guangxi, China. Methods: We conducted a cross-sectional study of outpatient antibiotic prescriptions in 2014 for children aged 2–14 years with upper respiratory infections (URI). Twenty health facilities were randomly selected, including four county hospitals, eight township hospitals and eight village clinics. Prescriptions were extracted from the electronic records in the county hospitals and paper copies in the township hospitals and village clinics. Results: The antibiotic prescription rate was higher in township hospitals (593/877, 68%) compared to county hospitals (2736/8166, 34%) and village clinics (96/297, 32%) (p < 0.001). Among prescriptions containing antibiotics, county hospitals were found to have the highest use rate of broad-spectrum antibiotics (82 vs 57% [township], vs 54% [village], p < 0.001), injectable antibiotics (65 vs 43% [township], vs 33% [village], p < 0.001) and multiple antibiotics (47 vs 15% [township], vs 0% [village], p < 0.001). Logistic regression showed that the likelihood of prescribing an antibiotic was significantly associated with patients being 6–14 years old compared with being 2–5 years old (adjusted odds ratio [aOR] = 1.3, 95% CI 1.2–1.5), and receiving care at township hospitals compared with county hospitals (aOR = 5.0, 95% CI 4.1–6.0). Prescriptions with insurance copayment appeared to lower the risk of prescribing antibiotics compared with those without (aOR = 0.8, 95% CI 0.7–0.9). Conclusions: Inappropriate use of antibiotics was high for outpatient childhood URI in the four counties of Guangxi, China, with the highest rate found in township hospitals. A significant high proportion of prescriptions containing antibiotics were broad-spectrum, by intravenous infusion or with multiple antibiotics, especially at county hospitals. Urgent attention is needed to address this challenge

    The role of the bronchial microvasculature in the airway remodelling in asthma and COPD

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    In recent years, there has been increased interest in the vascular component of airway remodelling in chronic bronchial inflammation, such as asthma and COPD, and in its role in the progression of disease. In particular, the bronchial mucosa in asthmatics is more vascularised, showing a higher number and dimension of vessels and vascular area. Recently, insight has been obtained regarding the pivotal role of vascular endothelial growth factor (VEGF) in promoting vascular remodelling and angiogenesis. Many studies, conducted on biopsies, induced sputum or BAL, have shown the involvement of VEGF and its receptors in the vascular remodelling processes. Presumably, the vascular component of airway remodelling is a complex multi-step phenomenon involving several mediators. Among the common asthma and COPD medications, only inhaled corticosteroids have demonstrated a real ability to reverse all aspects of vascular remodelling. The aim of this review was to analyze the morphological aspects of the vascular component of airway remodelling and the possible mechanisms involved in asthma and COPD. We also focused on the functional and therapeutic implications of the bronchial microvascular changes in asthma and COPD

    Partial pulmonary embolization disrupts alveolarization in fetal sheep

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    BACKGROUND: Although bronchopulmonary dysplasia is closely associated with an arrest of alveolar development and pulmonary capillary dysplasia, it is unknown whether these two features are causally related. To investigate the relationship between pulmonary capillaries and alveolar formation, we partially embolized the pulmonary capillary bed. METHODS: Partial pulmonary embolization (PPE) was induced in chronically catheterized fetal sheep by injection of microspheres into the left pulmonary artery for 1 day (1d PPE; 115d gestational age; GA) or 5 days (5d PPE; 110-115d GA). Control fetuses received vehicle injections. Lung morphology, secondary septal crests, elastin, collagen, myofibroblast, PECAM1 and HIF1 alpha abundance and localization were determined histologically. VEGF-A, Flk-1, PDGF-A and PDGF-R alpha mRNA levels were measured using real-time PCR. RESULTS: At 130d GA (term approximately 147d), in embolized regions of the lung the percentage of lung occupied by tissue was increased from 29 +/- 1% in controls to 35 +/- 1% in 1d PPE and 44 +/- 1% in 5d PPE fetuses (p < 0.001). Secondary septal crest density was reduced from 8 +/- 0% in controls to 5 +/- 0% in 1d PPE and 4 +/- 0% in 5d PPE fetuses (p < 0.05), indicating impaired alveolar formation. The deposition of differentiated myofibroblasts (23 +/- 1% vs 28 +/- 1%; p < 0.001) and elastin fibres (3 +/- 0% vs 4 +/- 0%; p < 0.05) were also impaired in embolized lung regions of PPE fetuses compared to controls. PPE did not alter the deposition of collagen or PECAM1. At 116d GA in 5d PPE fetuses, markers of hypoxia indicated that a small and transient hypoxic event had occurred (hypoxia in 6.7 +/- 1.4% of the tissue within embolized regions of 5d PPE fetuses at 116d compared to 0.8 +/- 0.2% of tissue in control regions). There was no change in the proportion of tissue labelled with HIF1 alpha. There was no change in mRNA levels of the angiogenic factors VEGF and Flk-1, although a small increase in PDGF-R alpha expression at 116d GA, from 1.00 +/- 0.12 in control fetuses to 1.61 +/- 0.18 in 5d PPE fetuses may account for impaired differentiation of alveolar myofibroblasts and alveolar development. CONCLUSIONS: PPE impairs alveolarization without adverse systemic effects and is a novel model for investigating the role of pulmonary capillaries and alveolar myofibroblasts in alveolar formation
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