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31.

Background

Infection after revision total knee arthroplasty (TKA) for previous septic TKA can be a challenging problem to treat due to loss of bone stock and soft tissue integrity. In these cases, arthrodesis is a well-recognized salvage procedure.

Questions/Purposes

The aim of this retrospective study was to compare the results as described by a Visual Analogue Scale (VAS) and the Lequesne Algofunctional Score (LAS) of knee arthrodeses performed by using either an external fixator (EF) or an intramedullary nail (IM).

Methods

The study included 34 knee arthrodesis divided in two groups: first group included 12 patients treated with EF and the second group of 22 patients dealt with IM nail. Clinical and functional evaluation was performed using the VAS and the LAS. Full-length radiographs were used to verify limb length discrepancy.

Results

VAS and LAS results showed a substantial improvement relative to preoperative condition in both groups. However, the LAS was significantly better in the IM nail group. The mean leg length discrepancy was significantly greater (4.5 cm) in the first group than in the second one (0.8 cm). No recurrence of infection was observed in the EF group while there were three recurrent infections in the IM nail group.

Conclusion

Our study supported the existing literature and found that reinfection after revision TKA can be effectively treated with arthrodesis. In presence of massive bone loss, we recommend arthrodesis with IM nail used as an endoprosthesis, without bone-on-bone fusion, to produce a stable and painless knee, while preserving the limb length. Use of an IM nail allowed us to get a better functional result than EF.  相似文献   
32.

Purpose

Maximal oxygen consumption (VO2max) and oxygen consumption at anaerobic threshold (VO2AT) are commonly measured parameters to test elite soccer players; however, studies relating metabolic parameters of professional soccer players with performance and best fitting to the field role are scarce. Our aim was to study the relations of VO2max and VO2AT with the field role of elite soccer players to generate a robust dataset with a solid statistical analysis.

Method

Over a 12-year period we performed 953 field evaluation tests of VO2 max and VO2AT on 450 elite soccer players of 13 professional teams by incremental, continuous and exhausting test modified from Conconi’s test. Statistical analysis was performed by one-way ANOVA followed—when appropriate—by Tukey post hoc test. Effect size was evaluated by the Cohen D test and η partial squared test. Statistical significance was set for p < 0.05.

Results

VO2max mean values increased at the beginning of season by 1.073 ± 0.06 respect to pre-season then decreased again up to pre-season levels and remained stable, while VO2AT did not change during time. VO2max differences were also related to players’ field role. VO2max mean value for Goalkeeper was 50.85 ± 4.2, for central Defender was 57.58 ± 4.3, for Winger-sides back was 60.53 ± 5.02, for Midfielder was 59.53 ± 5.08, for Forward was 56.52 ± 4.14. On the contrary, as expected, VO2AT percentage variations among the roles were not significant.

Conclusions

VO2max is the choice parameter to consider for the metabolic compliance of athletes to the field role requirements, consequently influencing training programs, recovery and injury prevention strategies.
  相似文献   
33.
The cognitive characteristics of highly hypnotizable subjects (Highs) allow them to easily modify their cognitive and autonomic state. Under hypnosis, Highs receiving cognitive, fear-like stimulation exhibit the cardiovascular changes typical of fear/stress, but also show an EEG pattern indicating a balance between fear-induced arousal and hypnotic relaxation. Indeed, hypnosis is effective in the attenuation of both emotional experience and behaviour (emotional numbing). The aim of the present experiment was to investigate the possible different role of relaxation and suggestion in hypnotic emotional numbing. Tonic skin conductance, respirogram, heart rate, systolic and diastolic blood pressure were recorded in 3 groups of hypnotized subjects: Group 1 received a fearful guided imagery associated with threat suggestions (Threat) followed by the same fearful suggestion associated with numbing instructions (relaxation and "No-Threat"); Group 2 received the same instructions in the opposite order of presentation; Group 3 received the fearful suggestion with threat instructions twice. The numbing suggestion reduced fear-related emotional experience and autonomic responses; if No-Threat preceded Threat, the heart rate, heart rate variability and blood pressure were also reduced during Threat, in spite of self reports of high negative emotion. Thus, 1) the subjective experience and the autonomic response to fear can be dissociated; 2) the efficacy of numbing suggestion is extended to a subsequent Threat stimulation; 3) habituation does not contribute to the numbing effect. The results indicate that the specific numbing suggestion is the main factor in hypnotic modulation of the experience of fear.  相似文献   
34.
Background: The EMCDDA, through its network of National Focal Points, collects information on the quality assurance systems for drugs-related interventions across European countries. European National Drug Strategies include recommendations for systems and approaches for the assurance of the quality of interventions.

Methods: We searched National Drug Strategies for elements related to quality assurance in drug demand reduction and summarised information through questionnaires administered to the EMCDDA Network of National Focal Points.

Results: In total, 15 National Drug Strategies and 60 questionnaires were analysed. Almost all the strategies include quality-related topics. Frequently, the Ministry of Health leads quality assurance although sometimes jointly with the Ministries of Education, Labour, Family and Social Welfare. Accreditation systems are common, but implemented in different ways. Training and education are widely provided, for the vast majority of countries, consisting of short-term training to keep professionals updated. Guidelines and Standards are gathering momentum as the major tools for the implementation of evidence-based recommendations and are usually available across countries.

Conclusions: Although the evidence base for interventions in drug demand reduction is becoming available and accepted, attention needs to be given to implementation issues. The European countries are rapidly moving towards paying greater attention to the quality of interventions.  相似文献   
35.
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37.

Background

The nontechnical and team skills of surgical teams are critical for safety and efficiency in the operating room. Assessment of nontechnical and team skills can facilitate improvement by encouraging both self-reflection and team reflection, identifying training needs, and informing operating room (OR) team training approaches. The observational teamwork assessment for surgery (OTAS) tool is a well-validated and robust tool for capturing teamwork in the operating room. The aims of the present study were to systematically adapt and refine the OTAS for German-speaking OR staff and to test the adapted assessment tool (OTAS-D) for psychometric properties and metric equivalence.

Methods

The study was carried out in three stages: at stage 1, OTAS was translated into German. At stage 2, experienced German OR experts (surgeons, OR nurses, anesthetists) were interviewed. At stage 3, two blinded assessors observed 11 general surgical operations (general surgical and vascular procedures) and interrater reliability was tested for refined OTAS-D behavioral exemplars and scorings.

Results

The German OR experts confirmed the applicability and content validity of the vast majority of translated behavioral exemplars. After their evaluation, 32 items were changed slightly, six were changed substantially, and one item was added. During observations, perfect and substantial interobserver agreement was found for 77 behavioral exemplars (67.1 % of the items, kappa coefficient >0.60). Rating at all OTAS behaviors showed acceptable levels of reliability (intraclass correlation coefficients >0.72).

Conclusions

The OTAS-D is a tool for valid and reliable assessment of nontechnical skills that contribute to safe and effective surgical performance in ORs staffed by German-speaking professionals. Furthermore, our study serves as an example for systematically adapting and customizing well-established observational tools across different healthcare environments.  相似文献   
38.
Endothelial dysfunction begins in early CKD and contributes to cardiovascular mortality. HDL is considered antiatherogenic, but may have adverse vascular effects in cardiovascular disease, diabetes, and inflammatory conditions. The effect of renal failure on HDL properties is unknown. We studied the endothelial effects of HDL isolated from 82 children with CKD stages 2–5 (HDLCKD), who were free of underlying inflammatory diseases, diabetes, or active infections. Compared with HDL from healthy children, HDLCKD strongly inhibited nitric oxide production, promoted superoxide production, and increased vascular cell adhesion molecule-1 expression in human aortic endothelial cells, and reduced cholesterol efflux from macrophages. The effects on endothelial cells correlated with CKD grade, with the most profound changes induced by HDL from patients on dialysis, and partial recovery observed with HDL isolated after kidney transplantation. Furthermore, the in vitro effects on endothelial cells associated with increased aortic pulse wave velocity, carotid intima-media thickness, and circulating markers of endothelial dysfunction in patients. Symmetric dimethylarginine levels were increased in serum and fractions of HDL from children with CKD. In a longitudinal follow-up of eight children undergoing kidney transplantation, HDL-induced production of endothelial nitric oxide, superoxide, and vascular cell adhesion molecule-1 in vitro improved significantly at 3 months after transplantation, but did not reach normal levels. These results suggest that in children with CKD without concomitant disease affecting HDL function, HDL dysfunction begins in early CKD, progressing as renal function declines, and is partially reversed after kidney transplantation.Patients with CKD no longer die from renal failure but from cardiovascular disease. There is an independent, graded association between a reduced eGFR and the risk of death and cardiovascular events.1 Typically, patients with CKD develop calcification in the tunica media of their arteries,2 but a concomitant process of endothelial damage leading to atherosclerosis is also3 present beginning in predialysis CKD.4,5LDL is crucially involved in the pathogenesis of atherosclerotic cardiovascular disease in the general population,6 whereas HDL is thought to be antiatherogenic by promoting reverse cholesterol transport and exerting direct protective endothelial effects.7 HDL from healthy participants increases the bioavailability of nitric oxide (NO) by activating endothelial NO synthase inducing vasodilation and decreasing arterial BP. Moreover, HDL diminishes the production of reactive oxygen species such as superoxide (SO) radicals, which have been demonstrated to reduce NO bioavailability leading to endothelial dysfunction and promoting atherogenesis. However, recent evidence suggests that HDL may lose its vasoprotective properties in patients with manifest cardiovascular disease (e.g., coronary artery disease), diabetes, or inflammatory disease states (e.g., antiphospholipid syndrome).810 Similarly, in adults on dialysis, HDL has reduced cholesterol efflux capacity and proinflammatory effects on mononuclear cells.1113 Observational studies have shown a strong association between high HDL levels and reduced risk of cardiovascular disease in the general population14 but not in dialysis patients.15Cardiac and vascular damage has also been documented in children on dialysis,2,16,17 and cardiovascular disease accounts for the majority of deaths in pediatric dialysis patients.17 In contrast with adult patients with CKD, in whom cardiovascular risk factors such as diabetes dyslipidemia, hypertension, and smoking are highly prevalent,18 CKD in children is mainly caused by inherited disorders such as malformations of the kidney or urinary tract.18 Accordingly, examining HDL function in children who are free of “traditional” cardiovascular risk factors and underlying inflammatory diseases and who are nonsmokers gives us an unique opportunity to study the effects of renal failure on the vascular functions of HDL.We studied the endothelial properties of HDL in a cohort of children at different stages of CKD on dialysis and after transplantation and compared them with healthy children. Furthermore, to determine the clinical relevance of in vitro effects of HDL, we examined its relationship with clinical measures of the vascular phenotype as well as circulating markers of endothelial dysfunction. Finally, to show a causal link between renal function and HDL properties, we examined children on dialysis and 3 months after kidney transplantation. This study allowed us to examine when HDL dysfunction develops during the natural history of renal decline, its effects on vascular function, and the potential for recovery after kidney transplantation.  相似文献   
39.
40.
Forensic Science, Medicine and Pathology - Some previously reported cases of brain evisceration in catastrophic craniocerebral injuries showed the presence of brain swelling. The aim of this study...  相似文献   
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