Bone Density and Texture from Minimally Post-Processed Knee Radiographs in Subjects with Knee Osteoarthritis

Abstract

Plain radiography is the most common modality to assess the stage of osteoarthritis. Our aims were to assess the relationship of radiography-based bone density and texture between radiographs with minimal and clinical post-processing, and to compare the differences in bone characteristics between controls and subjects with knee osteoarthritis or medial tibial bone marrow lesions (BMLs). Tibial bone density and texture was evaluated from radiographs with both minimal and clinical post-processing in 109 subjects with and without osteoarthritis. Bone texture was evaluated using fractal signature analysis. Significant correlations (p < 0.001) were found in all regions (between 0.94 and 0.97) for calibrated bone density between radiographs with minimal and clinical post-processing. Correlations varied between 0.51 and 0.97 (p < 0.001) for FD_Ver texture parameter and between − 0.10 and 0.97 for FD_Hor. Bone density and texture were different (p < 0.05) between controls and subjects with osteoarthritis or BMLs mainly in medial tibial regions. When classifying healthy and osteoarthritic subjects using a machine learning-based elastic net model with bone characteristics, area under the receiver operating characteristics (ROCAUC) curve was 0.77. For classifying controls and subjects with BMLs, ROCAUC was 0.85. In conclusion, differences in bone density and texture can be assessed from knee radiographs when using minimal post-processing.

http://bit.ly/2SyWdOu

Current Challenges and Emergent Technologies for Manufacturing Artificial Right Ventricle to Pulmonary Artery (RV-PA) Cardiac Conduits

Abstract

Despite advances in modern surgery, congenital heart disease remains a medical challenge and major cause of infant mortality. Valved conduits are routinely used to surgically correct blood flow in hearts with congenital malformations by connecting the right ventricle to the pulmonary artery (RV-PA). This review explores the current range of RV-PA conduits and describes their strengths and disadvantages. Homografts and xenografts are currently the primary treatment modalities, however both graft types have limited biocompatibility and durability, and present a disease transmission risk. Structural deterioration of a replaced valve can lead to pulmonary valve stenosis and/or regurgitation. Moreover, as current RV-PA conduits are of a fixed size, multiple subsequent operations are required to upsize a valved conduit over a patient's lifetime. We assess emerging biomaterials and tissue engineering techniques with a view to replicating the features of native tissues, including matching the durability and elasticity required for normal fluid flow dynamics. The benefits and limitations of incorporating cellular elements within the biomaterial are also discussed. Present review demonstrates that an alignment of medical and engineering disciplines will be ultimately required to produce a biocompatible and high-functioning artificial conduit.

http://bit.ly/2DDwYjD

Different light-activation systems associated with dental bleaching: a systematic review and a network meta-analysis

Abstract

Objectives

A systematic review and a network meta-analysis were performed to answer the following research question: "Is there any light-activation protocol capable of improving color change efficacy when associated with an in-office bleaching gel in adults?"

Material and methods

A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and SIGLE without date and/or language restrictions in April 23, 2017 (updated on March 30, 2018). IADR abstracts (1990–2018), unpublished and ongoing trial registries, dissertations, and theses were also searched. Only randomized clinical trials conducted in adults that included at least one group treated with in-office dental bleaching with light activation were included. The risk of bias (RoB) was evaluated using the Cochrane Collaboration tool. A random-effects Bayesian-mixed treatment comparison (MTC) model was used to combine light-activated versus light-free in-office bleaching with direct light-free comparison trials. A meta-analysis with independent analysis (high- and low-concentrate hydrogen peroxide [HP]) was conducted for color change (∆E*, ∆SGU).

Results

After the removal of duplicates, title, and abstract screening, 28 studies remained. Nine were considered to be at a low RoB, five were at a high RoB, and the remaining were at an unclear RoB. The MTC analysis showed no significant difference in color change (ΔE* and ΔSGU) between light-activation protocols and light-free in-office bleaching, regardless of the HP concentration in the efficacy of the bleaching.

Conclusion

No type of light-activated in-office bleaching was superior to light-free in-office bleaching for both high- and low-concentrate in-office bleaching gels (PROSPERO—CRD42017078743).

Clinical relevance

Although many times dental professionals use "laser whitening" as a form of marketing, this study confirmed that no type of light-activation for in-office bleaching can improve the bleaching efficacy.

http://bit.ly/2IeD6UT

Fluorescence-guided neurosurgery—neuro-oncology and cerebrovascular applications (2019) by Constantinos G. Hadjipanayis and Walter Stummer (eds.)

http://bit.ly/2SPfnyF

Influence of processing parameters on barrier properties of nitrile rubber/nanoclay nanocomposite membrane against organic solvent

Abstract

The present study focuses on the influence of layered silicate nanoparticles on barrier properties of a rubber/nanoclay nanocomposite (RCN). Most of the previous works deal with the importance of the surface chemistry of the nanoclay on the performance of the material. In this paper were rather investigated the effect of the processing conditions. Elastomer nanocomposites based on nitrile butadiene rubber and layered silicate nanoparticles were prepared using three different techniques: chemical dissolution, mixing in an internal mixer and melt-mixing with a twin-screw extruder. Chemical resistance to methanol was assessed using gravimetric method and mass transfer kinetic parameters were then deduced. Mass uptake results clearly showed that extruded RCN exhibited the highest chemical resistance. Barrier properties were subsequently correlated to the morphological structure of the rubber/nanoclay system. Small-angle X-ray diffraction patterns indicated that this improvement was due to a preferred alignment of the nanoparticle in the structure. Further, inspection revealed an anisotropic orientation profile of the nanoclay layers over the thickness of a sheet-like extruded material. In addition, a neat decrease of chemical sorption was spotted with mixing and chemically processed RCN materials over the unfilled rubber. The state of dispersion of clay nanoparticles was also probed in these nanocomposites using X-ray diffraction. The findings suggested an intercalation during processing. Further, transmission electron microscopy observations were suggesting a bimodal state of dispersion over spotting individual nClay platelets along with the layered stacks. Improvement of mass transport kinetic parameters was recorded over increasing the shear stress as well as the residence time when RCN were prepared in the internal mixer.

http://bit.ly/2tn92fx

Triple-S Lift for Facial Rejuvenation

Abstract

Background

Since the beginning of the last century, when the aesthetic rejuvenating surgery was first described, there have been great changes in tactics and methods for solving the problems of age-related facial changes. Since the first description of the superficial muscular aponeurotic system (SMAS), there have been two main approaches to influencing this structure. These are various types of SMAS plications and different in-depth and technique sub-SMAS liftings. Each of these approaches has its advantages and disadvantages.

Methods

We have developed and applied a face-lift technique that combines the advantages of both approaches. We call it the triple-S lift, which is based on three basic principles:

1. A short scar technique;

2. The safety SMAS (limited sub-SMAS dissection to anterior border of the masseter muscle);

3. The support system (a complex of ligatures in the sub-SMAS layer, which allows lifting and plication of the medial part of the SMAS simultaneously)

According to this method, there were 93 operations performed on 8 men and 85 women aged 38 to 72 years.

Results

The first clinical applications produced good results. The patients noted a high degree of satisfaction, and the level of complications was quite low. Since the technique has been performed for a short period of time, we demonstrate results of the 2-year period.

Conclusion

The described technique requires further study, but the first results suggest that this type of a surgical intervention is safe, easy to execute, and may be an option to choose for surgical correction of facial aging changes.

Level of Evidence IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

http://bit.ly/2SyYVTT

The Relationship Between the Preoperative Neutrophil-to-Lymphocyte Ratio and Postoperative Nausea and Vomiting in Patients Undergoing Septorhinoplasty Surgery

Abstract

Background

Postoperative nausea and vomiting (PONV) is one of the most common complications during the postoperative period. In the literature, there are many factors associated with PONV risk, but it is claimed that inflammation increases this risk. The neutrophil-to-lymphocyte ratio (NLR) is a cheap parameter to use in the diagnosis and follow-up of systemic inflammatory diseases. In this study, we aimed to investigate whether the preoperative NLR was a marker for PONV and to determine its relation with antiemetic use.

Methods

Eighty patients who were planned to undergo elective septorhinoplasty and were in ASA I–II were prospectively included in the study. The NLR value was calculated by dividing the number of neutrophils by the number of lymphocytes obtained from the preoperative complete blood count. The patients were divided into two groups of 40 patients: patients with an NLR < 2 (group 1) and patients with an NLR > 2 (group 2). Nausea and vomiting during the first 24 h in the recovery room and in the related clinic and antiemetic requirement were recorded.

Results

The rate of nausea–vomiting in the recovery room and in the postoperative 24-h period in group 1 was significantly lower than in group 2 (p < 0.05). The rate of use of antiemetics in the recovery room and in the postoperative 24-h period in group 1 was significantly lower than in group 2 (p < 0.05).

Conclusion

NLR values above 2 calculated in the preoperative period may be an indicator of PONV risk. Antiemetic prophylaxis may be given according to this value.

Level of Evidence IV

This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

http://bit.ly/2DIJluz