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101.

Background

Total knee arthroplasty (TKA) is the gold standard procedure for knee osteoarthritis. However, there have been conflicting reports concerning whether TKA is associated with modifications in patellar height. This controversy might be partially explained by the diversity of methods used to measure patellar height. Therefore, we aimed at assessing the reproducibility of 3 radiological indices commonly used to evaluate patellar height—Insall-Salvati (IS), Blackburne-Peel (BP), and Caton-Deschamps (CD) ratios. Additionally, we aimed at evaluating the short-term differences between preoperative and postoperative patellar heights as measured by those 3 methods.

Methods

Patellar heights were blindly measured by 2 researchers using IS, BP, and CD ratios in 203 knees. Interobserver agreement was evaluated by determination of intraclass correlation coefficients (ICC) and Bland-Altman plots. Preoperative and postoperative patellar heights were compared with Wilcoxon test. The association between postoperative pain and modifications in patellar height was assessed using Mann-Whitney U test.

Results

High interobserver agreement was found for IS (preoperative and postoperative ICC = 0.93), BP (preoperative ICC = 0.89; postoperative ICC = 0.91), and CD (preoperative ICC = 0.89; postoperative ICC = 0.90) ratios. Preoperative and postoperative patellar heights were not significantly different whatever the method used. Postoperative pain was reported after 23% procedures and was significantly associated with wider patellar height variations as measured by the BP ratio (P = .018).

Conclusion

The methods evaluated appear to be reproducible. Although patellar height tended to be lower when measured postoperatively, this difference was not significant for any of the methods studied.  相似文献   
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In an editorial board‐moderated debate format, two experts in prostate cancer surgery are challenged with presenting the key strategies in radical prostatectomy that improve urinary functional outcomes. Dr Bernardo Rocco was tasked with arguing the facts that support the anatomical preservation and reconstruction steps that improve urinary continence. Drs Christian Pavlovich and Sasha Druskin were tasked with arguing the facts supporting neurovascular bundle and high anterior release surgical planes that improve urinary continence. Associate Editor John Davis moderates the debate, and outlines the current status of validated patient questionnaires that can be used to evaluate urinary continence, and recent work that allows measuring what constitutes a ‘clinically significant’ difference that either or both of these surgical techniques could influence. A review of raw data from a publication from Dr Pavlovich's team demonstrates how clinically relevant differences in patient‐reported outcomes can be correlated to technique. A visual atlas is presented from both presenting teams, and Dr Davis demonstrates further reproducibility of technique. A linked video on this concept is available as a supplementary file.  相似文献   
104.
After the "mechanical era" in interventional cardiology (represented by balloon angioplasty and bare metal stent implantation), arrived the "local dispensing" era, began with the intracoronary delivery of antithrombotic or antirestenotic drugs. However, even drug eluting stents have some pitfalls and cannot be used in all clinical subsets. In this article we will review the significant data on the paclitaxel-coated balloons for the treatment of coronary artery disease. Particularly, we will review the rationale of this new treatment strategy, the preclinical data and will focus on available clinical studies in humans. After the initial boost of the paclitaxel coated balloons with the Paccocath technology in in-stent restenotic lesions, the experimentation of newer devices in native coronary arteries raised some concerns on their efficacy and safety. We will comment on this topic trying to understand the reasons of this failure, and will discuss on possible future developments and applications for these devices for the treatment of coronary artery disease.  相似文献   
105.
BackgroundThe emergence and media coverage of COVID-19 may have affected influenza search patterns, possibly affecting influenza surveillance results using Google Trends.ObjectiveWe aimed to investigate if the emergence of COVID-19 was associated with modifications in influenza search patterns in the United States.MethodsWe retrieved US Google Trends data (relative number of searches for specified terms) for the topics influenza, Coronavirus disease 2019, and symptoms shared between influenza and COVID-19. We calculated the correlations between influenza and COVID-19 search data for a 1-year period after the first COVID-19 diagnosis in the United States (January 21, 2020 to January 20, 2021). We constructed a seasonal autoregressive integrated moving average model and compared predicted search volumes, using the 4 previous years, with Google Trends relative search volume data. We built a similar model for shared symptoms data. We also assessed correlations for the past 5 years between Google Trends influenza data, US Centers for Diseases Control and Prevention influenza-like illness data, and influenza media coverage data.ResultsWe observed a nonsignificant weak correlation (ρ= –0.171; P=0.23) between COVID-19 and influenza Google Trends data. Influenza search volumes for 2020-2021 distinctly deviated from values predicted by seasonal autoregressive integrated moving average models—for 6 weeks within the first 13 weeks after the first COVID-19 infection was confirmed in the United States, the observed volume of searches was higher than the upper bound of 95% confidence intervals for predicted values. Similar results were observed for shared symptoms with influenza and COVID-19 data. The correlation between Google Trends influenza data and CDC influenza-like-illness data decreased after the emergence of COVID-19 (2020-2021: ρ=0.643; 2019-2020: ρ=0.902), while the correlation between Google Trends influenza data and influenza media coverage volume remained stable (2020-2021: ρ=0.746; 2019-2020: ρ=0.707).ConclusionsRelevant differences were observed between predicted and observed influenza Google Trends data the year after the onset of the COVID-19 pandemic in the United States. Such differences are possibly due to media coverage, suggesting limitations to the use of Google Trends as a flu surveillance tool.  相似文献   
106.
We have isolated a new phospholipase A2 (MiDCA1) from the venom of the coral snake Micrurus dumerilii carinicauda. This toxin, which had a molecular mass of 15,552Da, shared high sequence homology with the PLA2 toxins MICNI A and B from Micrurus nigrocinctus venom (77.7% and 73.1%, respectively). In chick biventer cervicis preparations, MiDCA1 produced concentration- and time-dependent neuromuscular blockade that reached 100% after 120 min (2.4 microM, n = 6); contractures to exogenously applied carbachol (8 microM) and KCl (13 mM) were still seen after complete blockade. In mouse phrenic-nerve diaphragm preparations, MiDCA1 (2.4 microM; n = 6) caused triphasic changes followed by partial neuromuscular blockade. Intracellular recordings of end-plate potentials (EPPs) and miniature end-plate potentials (MEPPs) from mouse diaphragm preparations showed that MiDCA1 increased the quantal content by 386+/-12% after 10 min (n = 14; p<0.05) and caused a triphasic change in the frequency of MEPPs. MiDCA1 also decreased the resting membrane potential, an effect that was prevented by tetrodotoxin and/or low extracellular calcium, but not by d-tubocurarine. The toxin increased the amplitude of mouse sciatic-nerve compound action potentials by 30+/-9% (0.6 microM; p<0.05). Potassium currents elicited in freshly dissociated dorsal root ganglia neurones were blocked by 31+/-1% (n = 4; p<0.05) in the presence of 2.4 microM MiDCA1. These results show that MiDCA1 is a new presynaptic phospholipase A2 that produces neuromuscular blockade in vertebrate nerve-muscle preparations. The triphasic effects seen in mammalian preparations and the facilitatory response were probably caused mainly by the activation of sodium channels, complemented by the blockade of nerve terminal potassium channels. The inability of d-turocurarine to prevent the depolarization by MiDCA1 indicated that cholinergic nicotinic receptors were not involved in this phenomenon.  相似文献   
107.
An in situ evaluation of the potential rehardening effect of fluoridated and non-fluoridated toothpastes with or without air polishing was conducted. Ten volunteers, using acrylic palatal appliances containing two bovine enamel blocks with artificial carious lesions, took part in this study. Four times a day, after the main meals and at night, the volunteers, in a habitual way, brushed their natural teeth with the dentifrice indicated to the experimental design and after that the appliances were put again into the mouth. They were divided into 4 different groups: G1 - control - non-fluoridated dentifrice; G2 - fluoridated dentifrice; G3 - non-fluoridated dentifrice, but having a previous prophylaxis using air polishing; G4 - fluoridated dentifrice and previous air polishing. The effects of treatments on enamel rehardening were evaluated in the blocks that were assessed by surface microhardness, and the percentage of surface microhardness change (%reh) was calculated in relation to the baseline values. The results showed that %reh was higher in the groups with fluoridated dentifrice, and professional prophylaxis did not have an additional effect in the groups of fluoridated dentifrices (p<0.05). The data suggested that, in the absence of fluoride, removal of dental plaque helped to increase the process of enamel rehardening.  相似文献   
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