498 research outputs found
The effect of surgical approach on the histology of the femoral head following resurfacing of the hip : analysis of retrieval specimens
Objectives: We aimed to determine the effect of surgical approach on the histology of the femoral head following resurfacing of the hip.
Methods: We performed a histological assessment of the bone under the femoral component taken from retrieval specimens of patients having revision surgery following resurfacing of the hip. We compared the number of empty lacunae in specimens from patients who had originally had a posterior surgical approach with the number in patients having alternative surgical approaches.
Results: We found a statistically significant increase in the percentage of empty lacunae in retrieval specimens from patients who had the posterior approach compared with other surgical approaches (p < 0.001).
Conclusions: This indicates that the vascular compromise that occurs during the posterior surgical approach does have long-term effects on the bone of the femoral head, even if it does not cause overt avascular necrosis
Kombination der Analyse von Black Carbon, PAK und organischen Geosorbenten in urbanen Böden als Indikator fĂŒr die BioverfĂŒgbarkeit von PAK
In den letzten Jahren hat die Bedeutung von aromatischen KohlenwasserstoffmolekĂŒlen in umweltrelevanten Fragestellungen zugenommen: ToxizitĂ€t und BioverfĂŒgbarkeit von polyzyklischen aromatischen Kohlenwasserstoffen (PAK), die Bindung dieser Substanzen an Geosorbenten und die damit verbundene reduzierte Freisetzungsrate, sowie die Differenzierung des organischen Kohlenstoffs (TOC) in Böden in reaktive und gering reaktive Kohlenstoffpools (Black Carbon) im Hinblick auf Kohlenstoffspeicherung, die Verwertbarkeit von Böden mit erhöhten TOC- und PAK-Gehalten und Biochar. Die Herkunft dieser aromatischen MolekĂŒle aus biogenen, petrogenen oder pyrogenen Quellen ist hierbei von besonderer Bedeutung, da sich die Bildungsmechanismen unterscheiden und ggf. charakteristische MolekĂŒle oder MolekĂŒl-Muster gebildet werden. PAK und Black Carbon sind eng miteinander verbunden, letztlich bestehen die gröĂeren Black Carbon-Strukturen wesentlich aus den zahlreichen PAK bzw. können aus diesen durch Koagulation gebildet werden. Andererseits können PAK als âmobile Phaseâ zwischen den gröĂeren 3-dimensionalen Kohlenwasserstoffstrukturen des Kerogen z. B. in Kohlen enthalten sein. Die Vielfalt der durch ĂŒberwiegend anthropogene Prozesse schlieĂlich in Böden vorliegenden Arten von TOC-haltigen technogenen Substraten sowie Gemischen ist groĂ und kann mittels organisch-petrographischer Methoden identifiziert und quantifiziert werden. In dieser Studie werden systematische ZusammenhĂ€nge zwischen petrogenen und pyrogenen PAK, Black Carbon anhand der AromatizitĂ€t und des Grades der aromatischen Kondensation (BenzenpolycarbonsĂ€uren(BPCA)-Methode mittels FlĂŒssigchromatographie-Massenspektrometrie) sowie der petrographischen mikroskopischen Analyse gezeigt. Als Probenset dienten RuĂe (z. B. Diesel, Holz), Aschen, Schlacken, Lignit, Braun- und Steinkohlen sowie Anthrazit, Bergematerial, Kohleschlamm, Holzkohlen, Kokse unterschiedlicher Herkunft, StĂ€ube, Rohöle, Teeröle sowie Böden mit Mischungen von technogenen Substraten aus dem Ruhrgebiet. HinzugefĂŒgte Literaturdaten bestĂ€tigen die Messergebnisse im Kohlenstoffkontinuum. Untersuchungen der Freisetzung von PAK in die wĂ€ssrige Phase sowie ihrer ResorptionsverfĂŒgbarkeit weisen auf ein allgemein geringes Potential im thermisch beeinflussten Teil des Kohlenstoffkontinuums hin
A qualitative study of cliniciansâ experience of a clinical trial for displaced distal radius fractures
Aims:Â The aim of this study was to explore cliniciansâ experience of a paediatric randomized controlled trial (RCT) comparing surgical reduction with non-surgical casting for displaced distal radius fractures.
Methods:Â Overall, 22 staff from 15 hospitals who participated in the RCT took part in an interview. Interviews were informed by phenomenology and analyzed using thematic analysis.
Results:Â Analysis of the findings identified the overarching theme of âovercoming obstaclesâ, which described the challenge of alleviating staff concerns about the use of non-surgical casting and recruiting families where there was treatment uncertainty. In order to embed and recruit to the Childrenâs Radius Acute Fracture Fixation Trial (CRAFFT), staff needed to fit the study within clinical practice, work together, negotiate treatment decisions, and support families.
Conclusion:Â Recruiting families to this RCT was challenging because staff were uncertain about longer-term patient outcomes, and the difficulties were exacerbated by interdisciplinary tensions. Strong family and clinician beliefs, coupled with the complex nature of emergency departments and patient pathways that differed site-by-site, served as barriers to recruitment. Cementing a strong research culture, and exploring familiesâ treatment preferences, helped to overcome recruitment obstacles
Being recovered: a qualitative study of parentsâ experience of their childâs recovery up to a year after a displaced distal radius fracture
Aims
The aim of this study was to explore parentsâ experience of their childâs recovery, and their thoughts about their decision to enrol their child in a randomized controlled trial (RCT) of surgery versus non-surgical casting for a displaced distal radius fracture.
Methods
A total of 20 parents of children from 13 hospitals participating in the RCT took part in an interview five to 11 months after injury. Interviews were informed by phenomenology and analyzed using thematic analysis.
Results
Analysis of the findings identified the theme âbeing recoveredâ, which conveyed: 1) parentsâ acceptance and belief that their child received the best treatment for them; 2) their memory of the psychological impact of the injury for their child; and 3) their pride in how their child coped with their cast and returned to activities. The process of recovery was underpinned by three elements of experience: accepting the treatment, supporting their child through challenges during recovery, and appreciating their childâs resilience. These findings extend our framework that highlights parentsâ desire to protect their child during early recovery from injury, by making the right decision, worrying about recovery, and comforting their child.
Conclusion
By one year after injury, parents in both treatment groups considered their child ârecoveredâ. They had overcome early concerns about healing, the appearance of the wrist, and coping after cast removal. Greater educational support for families during recovery would enable parents and their child to cope with the uncertainty of recovery, particularly addressing the loss of confidence, worry about reinjury, and the appearance of their wrist
Mogelijkheden voor verhoging van de stikstofefficiëntie : deskstudie in het kader van het project Nutriënten Waterproof, LNV-programma's systeeminnovatie open teelten (400-I en 400-III)
Het doel van deze deskstudie is in kaart brengen van de mogelijkheden van geleide bemestingsstrategieën. Deze strategieën moeten leiden tot minimale emissies van nutriënten. De strategieën dienen vervolgens te worden uitgewerkt voor de diverse systemen die in Nutriënten Waterproof worden aangelegd. Verder is het doel van deze deskstudie te bekijken hoe de ruimtelijke variabiliteit van de diverse percelen in kaart gebracht kan worden en hoe met deze variabiliteit omgegaan dient te worden in de bemestingsstrategieën. Deze deskstudie richt zich op stikstof
Requirement of respiratory support in acute bronchiolitis in infants is linked to endothelial and neutrophil activation
BACKGROUND: Evidence shows that activation of pulmonary vascular endothelium and neutrophils are involved in the pathophysiology of acute bronchiolitis. We hypothesized that levels of markers of endothelial activation and leukocyte counts are associated with requirement and duration of respiratory support. METHODS: Thirty-four infants with bronchiolitis and eight controls were included. Nasopharyngeal swabs and blood samples were taken at admission. Serum levels of Angiopoietin (Ang)-1, Ang-2, sP-selectin, sE-selectin, vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1), and leukocyte counts were measured. For univariate analysis, bronchiolitis cases were grouped into two groups, namely those not requiring and those requiring any form of respiratory support. To control for known risk factors for poor outcome (i.e., age, prematurity, and congenital heart disease), and for days post symptom onset, linear regression analysis was performed with duration of any type of respiratory support in days. RESULTS: Ang-2 levels, Ang-2/Ang-1 ratios, sE-selectin levels, immature neutrophil count, and neutrophil/lymphocyte ratio (NLR) were higher in acute bronchiolitis versus controls. Ang-2, and NLR levels were significantly higher, and lymphocyte counts significantly lower, in infants that required respiratory support versus those that did not. Ang-2 levels (ÎČ: .32, 95% confidence interval [CI]: 0.19-1.19) and NLR (ÎČ: .68, 95% CI: 0.17-1.19) were positive predictors for the duration of respiratory support. CONCLUSIONS: Markers of endothelial and neutrophil activation are associated with respiratory support for acute bronchiolitis. Admission Ang-2 levels and NLR may be promising markers to determine requirement of respiratory support and deserve further study
Effect of Parameters on Oxychlorination of Tert-Butyl Ethers
The effect of concentration, molar ratios of reagents, pH, and temperature on formation of chloro-organic products in reaction of tert-butyl ethers with chloride ions and hydrogen peroxide has been determined. A significant effect of Clâ ions and H2O2 molar ratios on the rate of chloro-organic product formation has been observed. Studies on oxychlorination of tert-butylethyl ether (ETBE) at pH 7, 3.5, and 2.5 have been carried out. It was found that introduction of hydronium ions into the reaction system considerably hastened the process of chloro-organic product formation. Hydronium ions contribute to the formation of the reactive tert-butyl carbocation, which undergoes secondary reactions in the presence of reactive forms of chlorine and oxygen. Moreover, the effect of temperature on ETBE (tert-butylethyl ether) and MTBE (tert-butylmethyl ether) conversions was verified. The reactions of MTBE and ETBE oxychlorination were carried out at temperatures of 5°C, 20°C, and 35°C
Impact of Human Genetic Variation on C-Reactive Protein Concentrations and Acute Appendicitis
BACKGROUND: Acute appendicitis is one of the most common abdominal emergencies worldwide. Both environmental and genetic factors contribute to the disease. C-reactive protein (CRP) is an important biomarker in the diagnosis of acute appendicitis. CRP concentrations are significantly affected by genetic variation. However, whether such genetic variation is causally related to appendicitis risk remains unclear. In this study, the causal relationship between single-nucleotide polymorphisms (SNPs) associated with circulating CRP concentrations and the risk and severity of acute appendicitis was investigated. METHODS: CRP concentrations in serum of appendicitis patients (n = 325) were measured. Appendicitis was categorized as complicated/uncomplicated and gangrenous/non-gangrenous. Imputed SNP data (n = 287) were generated. A genome-wide association study (GWAS) on CRP concentrations and appendicitis severity was performed. Intersection and colocalization of the GWAS results were performed with appendicitis and CRP-associated loci from the Pan-UKBB cohort. A functional-genomics approach to prioritize genes was employed. RESULTS: Thirteen percent of significant CRP quantitative trait loci (QTLs) that were previously identified in a large cohort of healthy individuals were replicated in our small patient cohort. Significant enrichment of CRP-QTLs in association with appendicitis was observed. Among these shared loci, the two top loci at chromosomes 1q41 and 8p23.1 were characterized. The top SNP at chromosome 1q41 is located within the promoter of H2.0 Like Homeobox (HLX) gene, which is involved in blood cell differentiation, and liver and gut organogeneses. The expression of HLX is increased in the appendix of appendicitis patients compared to controls. The locus at 8p23.1 contains multiple genes, including cathepsin B (CTSB), which is overexpressed in appendix tissue from appendicitis patients. The risk allele of the top SNP in this locus also increases CTSB expression in the sigmoid colon of healthy individuals. CTSB is involved in collagen degradation, MHC class II antigen presentation, and neutrophil degranulation. CONCLUSIONS: The results of this study prioritize HLX and CTSB as potential causal genes for appendicitis and suggest a shared genetic mechanism between appendicitis and CRPÂ concentrations
A multicentre prospective randomized equivalence trial of a soft bandage and immediate discharge versus current treatment with rigid immobilization for torus fractures of the distal radius in children
Aims
Torus fractures are the most common childhood fracture, accounting for 500,000 UK emergency attendances per year. UK treatment varies widely due to lack of scientific evidence. This is the protocol for a randomized controlled equivalence trial of âthe offer of a soft bandage and immediate dischargeâ versus ârigid immobilization and follow-up as per the protocol of the treating centreâ in the treatment of torus fractures.
Methods
Children aged four to 15-years-old inclusive who have sustained a torus/buckle fracture of the distal radius with/without an injury to the ulna are eligible to take part. Baseline pain as measured by the Wong Baker FACES pain scale, function using the Patient-Reported Outcomes Measurement Information System (PROMIS) upper limb, and quality of life (QoL) assessed with the EuroQol EQ-5D-Y will be collected. Each patient will be randomly allocated (1:1, stratified by centre and age group (four to seven years and â„ eight years) to either a regimen of the offer of a soft bandage and immediate discharge or rigid immobilization and follow-up as per the protocol of the treating centre.
Results
At day one, three, and seven, data on pain, function, QoL, immobilization, and analgesia will be collected. Three and six weeks after injury, the main outcomes plus data on complications, resource use, and school absence will be collected. The primary outcome is the Wong-Baker FACES pain scale at three days post-randomization. All data will be obtained through electronic questionnaires completed by the participants and/or parents/guardian
- âŠ