Phospholipase A2 levels in acute chest syndrome of sickle cell disease

Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS.     

Muscular adaptations to training programs using the Nordic hamstring exercise or the stiff-leg deadlift in rugby players

Sport Sciences for Health - Muscular responses to training programs with the Nordic hamstring exercise (NHE) have been widely investigated to understand its preventive effects on muscle strain...     

Detection and characterization of RNA tumor virus-specific DNA in cells.

RNA tumor virus-specific DNA in cells can be detected by its capacity to 1) alter the reassociation kinetics of labeled double-stranded product of viral RNA-directed DNA polymerase; 2) anneal single-stranded DNA (cDNA) synthesized by viral polymerase; or 3) hybridize labeled viral 70S (genomic) RNA. Duplexes formed with these procedures can be analyzed for fidelity of base pairing, and the integration of viral DNA into the host genome can be established with a simple but stringent technique. We illustrate this methodology as applied to detection of Rous sarcoma virus (RSV)-specific DNA in XC cells and of mouse mammary tumor virus (MMTV)-specific DNA in murine and human tissues.     

Comparison between percutaneous balloon valvuloplasty and open commissurotomy for mitral stenosis. A prospective and randomized study

Eighty patients with tight and pliable mitral stenosis were randomized in a prospective trial comparing percutaneous balloon valvuloplasty and open commissurotomy. Mitral valve area increased significantly in both groups immediately after the procedures. However, a decrease in mitral valve area occurred in both groups at 6, 12 and 24 months during the follow-up. There was no death in either group. Two patients had significant mitral regurgitation after percutaneous balloon valvuloplasty. After 24 months, all patients in the commissurotomy group and 97.4% of the patients in the balloon valvuloplasty group were in New York Heart Association functional class I or II.     

Stress distribution of different implant connections associated with multiple implant-supported prostheses

Abstract

In some clinical situations, the clinician may encounter previously installed implants that should be associated with other implants for a proper rehabilitation. The aim of this study was to evaluate the biomechanical behaviour of a multiple prosthesis joined by different implant connections using photoelasticity. Photoelastic models with a screwed fixed prosthesis supported by implants with different connection systems (Morse taper, external hexagon, internal hexagon, and Flexcone), and different combinations among them, were fabricated. Each assembly was placed in a circular polariscope, and axial and oblique (45°) loads of 100 N were applied on the occlusal surface of the crowns. The fringe patterns were photographed and the analysis was performed by counting the number of high-intensity fringes and also according to the stress distribution region where they appeared. Among implants of the same connection, the external connections obtained a greater number of high intensity fringes when compared to the internal connections. From the biomechanical point of view, the association between different types of connections obtained positive results.     

Accuracy of CAD-CAM systems for removable partial denture framework fabrication: A systematic review

Statement of problemRemovable partial dentures (RPDs) are traditionally made by casting, a complex, error-prone, and time-consuming process. Computer-aided design and computer-aided manufacturing (CAD-CAM) RPD systems may simplify the clinical steps and minimize errors; however, the accuracy of CAD-CAM RPD systems is unclear.PurposeThe purpose of this systematic review was to determine whether CAD-CAM systems are accurate for the manufacturing of RPD frameworks.Material and methodsA literature search was conducted through Medline-PubMed, Scopus, Lilacs, Web of Science, and Cochrane Library databases using specific keywords for articles published up to November 2019. Three reviewers obtained data and compared the results. All studies evaluated the framework accuracy or fit of prostheses fabricated with conventional and digital techniques.ResultsA total of 7 articles, 2 clinical studies, and 5 in vitro studies that complied with the inclusion criteria were evaluated. One in vitro study compared indirect (extraoral) and direct (intraoral) scanning for partially edentulous ridges and shows that digital scans were better than conventional impressions in terms of trueness. In the other studies included, although the frameworks analyzed had clinically acceptable discrepancies (<311 μm), the material influenced the fit. Polyetheretherketone (PEEK) showed better fit than traditional metal cast RPDs. Co-Cr alloy RPDs produced by rapid prototyping exhibited the highest discrepancies when produced by sintering laser melting.ConclusionsThe results show that the digital technique for RPD frameworks is accurate. In the studies included, the analyzed frameworks had clinically acceptable gaps, but the results were heterogeneous among studies because the articles used different measurement methods with small sample sizes. Few studies discussed the long-term clinical performance. The digital technique for RPD frameworks was accurate because the misfits and mismatches found in in vitro and clinical studies were within the acceptable clinical limit for RPDs.     

Peripheral dentinogenic ghost cell tumor—report of two cases and review of the literature

Oral and Maxillofacial Surgery - Peripheral dentinogenic ghost cell tumor (DGCT) is a rare and non-aggressive benign odontogenic tumor. They usually affect the elderly and are predominantly located...