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1.
«Severe silicosis due to diatomaceous earth in dental alginate: a necropsy study»Background:Severe silicosis from occupational exposure to calcined diatomaceous earth has been observed in the past, due to the high-temperature transformation of amorphous silica in crystalline phases, mainly cristobalite. In dental alginate production and use a silica exposure may be underestimated. Objectives: To describe the clinical picture, the scenario and pattern of occupational exposure to silica and the corresponding necroscopic findings of a case of silicosis in a worker engaged in the production of alginates for dental use.Methods:A commercial sample of calcinated diatomaceous earth and necroscopic lung samples were analysed by scanning electron microscopy (SEM-EDS) and X-ray diffraction (XRD) for the quali-quantitative determination of crystalline silica. Material safety data sheets (MSDSs) of diatomaceous earth produced in 2002 and 2018 were examined to assess the information content on silicosis risk. Clinical findings and post-mortem examinations of the worker are evaluated.Results:A cristobalite concentration of 36% (wt/wt) was determined in the diatomaceous earth sample and a large amount of diatom fragments were observed in lung samples. The DRX spectra indicated the presence of cristobalite either in the bulk sample or in the lung tissues. The MSDS dated 2002 reported the presence of SLC up to 63% with cristobalite concentrations <60%, and the resulting risk of silicosis, while the MSDS dated 2018 and referred to a commercial product currently on the market indicated a concentration of cristobalite <1% and no risk of silicosis. The worker was suffering from a severe silicosis, histologically confirmed by necropsy.Conclusion:The present case-study revealed that the risk of silicosis from calcined diatomaceous earths used to produce dental alginates has been ignored. The lack of engineering controls and personal protection measures led to a high cristobalite lung burden, consistent with the development of a severe silicosis that were a contributing factor of death. A MSDS of a commercial product currently on the market does not report this serious hazard.Key words: Silicosis, diatomaceous earth, dental alginate  相似文献   
2.
European Archives of Oto-Rhino-Laryngology - Limited approach septoplasty (LAS) follows the principle of respecting nasal structures and aims to minimize complications while ensuring proper nasal...  相似文献   
3.
BACKGROUNDIn press-fit total hip arthroplasty (THA) ceramic-on-ceramic (CoC) bearings are a potential for overcoming the wear that is seen in ceramic-on-polyethylene (CoPE) bearings, and can lead to wear-induced osteolysis, resulting in loosening of the implant. However, CoC bearings show disadvantages as well, such as squeaking sounds and being more fragile, which can cause ceramic head or liner fracture. Because comparative long-term studies are limited, the objective of this study was to determine the long-term difference in wear, identify potential predictive factors for wear, investigate radiological findings such as osteolysis, and evaluate clinical functioning and complications between these bearings.AIMTo determine 10-year differences in wear, predictive factors for wear, and investigate radiological findings and clinical functioning between CoC and CoPE.METHODSThis observational prospective single-center cohort study with a 10-year follow-up includes a documented series of elective THAs. Primary outcome was wear measured by anteroposterior (AP) radiographs. Secondary outcomes were potential predictive factors for wear, complications during follow-up, Harris hip score (HHS), and radiological findings such as presence of radiolucency, osteolysis, atrophy, and hypertrophy around the cup. Due to the absence of wear in the CoC group, stratified analysis to identify risk factors for wear was only performed in the CoPE group by use of univariate linear regression analysis. HHS was expressed as a change from baseline and the association with bearing type was assessed by use of multivariate linear regression analysis, adjusted for potential confounders.RESULTSA total of 17 CoPE (63.0%) and 25 CoC (73.5%) cases were available for follow-up and showed a linear wear of respectively 0.130 mm/year (range 0.010; 0.350) and 0.000 mm/year (range 0.000; 0.005), which was significant (P < 0.001) between both groups. Wear always occurred in the cranial direction. Cup inclination was the only predictive factor for polyethylene (PE) wear. No dislocations, ceramic head, or liner fractures were seen. The HHS showed a mean change from baseline of 37.1 points (SD 18.5) in the CoPE group and 43.9 (SD 17.0) in the CoC group. This crude difference of 6.8 (range -5.2; 18.7) in favor of the CoC group was not significant (P = 0.26) and was not significant when adjusted for age, gender, and diagnosis either (P = 0.99). No significant differences in complications and radiological findings were seen between groups. CONCLUSIONCoC bearing shows lower wear rates compared to CoPE at 10-year follow-up with cup inclination as a predictive factor for wear and no differences in complications, HHS, and radiological findings.  相似文献   
4.
5.
Inflammatory bowel disease (IBD) could be associated with several extra-intestinal manifestations (EIMs) involving musculoskeletal, hepatopancreatobiliary, ocular, renal, and pulmonary systems, as well as the skin. In the last years, hidradenitis suppurativa (HS) is acquiring an increasing interest. IBD, especially Crohn’s disease (CD), is among the most reported associated diseases in HS patients. The aim of this paper is to give a brief overview of data showing a possible epidemiologic and pathogenetic association between IBD and HS. We performed a pooled-data analysis of four studies and pooled prevalence of HS in IBD patients was 12.8%, with a 95%CI of 11.7%-13.9%. HS was present in 17.3% of subjects with CD (95%CI: 15.5%-19.1%) and in 8.5% of UC patients (95%CI: 7.0%-9.9%). Some items, especially altered immune imbalance, are generally involved in IBD pathogenesis as well as invoked by HS. Smoking is one of the most relevant risk factors for both disorders, representing a predictor of their severity, despite, actually, there being a lack of studies analyzing a possible shared pathway. A role for inheritance in HS and CD pathogenesis has been supposed. Despite a genetic susceptibility having been demonstrated for both diseases, further studies are needed to investigate a genetic mutual route. Although the pathogenesis of IBD and HS is generally linked to alterations of the immune response, recent findings suggest a role for intestinal and skin microbiota, respectively. In detail, the frequent finding of Staphylococcus aureus and coagulase-negative staphylococci on HS cutaneous lesions suggests a bacterial involvement in disease pathogenesis. Moreover, microflora varies in the different cutaneous regions of the body and, consequently, two different profiles of HS patients have been identified on these bases. On the other hand, it is well-known that intestinal microbiota may be considered as “the explosive mixture” at the origin of IBD despite the exact relationship having not been completely clarified yet. A better comprehension of the role that some bacterial species play in the IBD pathogenesis may be essential to develop appropriate management strategies in the near future. A final point is represented by some similarities in the therapeutic management of HS and IBD, since they may be controlled by immunomodulatory drugs. In conclusion, an unregulated inflammation may cause the lesions typical of both HS and IBD, particularly when they coexist. However, this is still a largely unexplored field.  相似文献   
6.

Background:

Transapical off-pump mitral valve intervention with neochord implantation for degenerative mitral valve disease have been recently introduced in the surgical practice. The procedure is performed under 2D-3D transesophageal echocardiography guidance.

Methods:

The use of 3D real-time transesophageal echocardiography provides more accurate information than 2D echocardiography only in all the steps of the procedure. In particular 3D echocardiography is mandatory for preoperative assessment of the morphology of the valve, for correct positioning of the neochord on the diseased segment, for the final tensioning of the chordae and for the final evaluation of the surgical result.

Result and Conclusion:

This article is to outline the technical aspects of the transesophageal echocardiography guidance of the NeoChord procedure showing that the procedure can be performed only with a close and continuous interaction between the anesthesiologist and the cardiac surgeon.  相似文献   
7.
The objective of the present study was to observe the effect of positioning of the mandible on the accuracy of cross-sectional images obtained by reformatting computerized tomographic (CT) scans. An additional aim was to evaluate the ability of a software program (DentalVox, Era Scientific) to reconstruct these measurements on the reformatted images, regardless of the positioning of the mandible, accurately and without distortion. The test was carried out by examining a partially edentulous dry human mandible with an acrylic radiologic template. Through the use of an acrylic glass support, the mandible was positioned at angles of 0, 10, 15, 20, and 30 degrees relative to the scanning gantry, and a series of CT scans was performed that provided five sets of axial images. Each set of original axial images was reformatted by the DentalVox software, used first in its basic function, which is typical of all software for axial CT measurement (control group), and again in its function of site-specific multiplanar reconstruction (test group). The results showed that the position of the mandible in relation to the CT gantry can influence the precision of the linear measurements. The error ranged from 2% to 51%. The DentalVox software allowed the reconstruction of cross-sectional images with very little distortion regardless of the mandibular position.  相似文献   
8.
9.
During a minimally invasive implantation technique, the outflow graft of left ventricular assist device (LVAD) is tunnelled blindly through the pericardium or left pleura, with an inability to assess for twisting or malposition. Three-dimensional computed tomography scan (CT-scan) has a role in qualitative evaluation of the different outflow tract configurations. The different surgical minimally invasive approaches include: (a) mini-sternotomy and left mini-thoracotomy, (b) right mini-thoracotomy and left mini-thoracotomy, (c) subclavian artery access and left mini-thoracotomy. The outflow graft could be anastomosed to the left axillary artery or the ascending aorta. CT-scan reconstruction using syngo InSpace4D (Siemens, Muenchen, Germany) was used to provide fast segmentation and high-resolution images. The 3D reconstructions permit an evaluation of different anastomosis configurations and to assess the route of outflow graft.  相似文献   
10.
BACKGROUND Polyethylene(PE) particles produced by wear of the acetabular insert are thought to cause osteolysis and thereby aseptic loosening of the implant in total hip arthroplasty(THA). As highly cross-linked polyethylene(HXLPE) is presumed to give lower wear rates, in vivo studies are needed to confirm this.AIM To compare the wear of REXPOL, a HXPLE, with conventional PE within the first five years after implantation using Roentgen stereophotogrammetric analysis(RSA).METHODS Patients were randomised to receive either a HXLPE(REXPOL) or a conventional PE insert during primary THA. RSA images were obtained directly postoperative and after 6 wk, 12 wk, 6 mo, 12 mo, 24 mo and five years. Functional outcomes were assessed using the Hip Injury and Osteoarthritis Outcome Score and Harris Hip Score at baseline and five years after surgery.RESULTS The HXLPE(REXPOL) showed less wear in the latero-medial direction. Significant wear rates of conventional PE were seen in the latero-medial and center-proximal direction and in volume and corrected volume, whereas the REXPOL did not show these outcomes over time. Improvement from baseline in functional outcome did not significantly differ.CONCLUSION Total 3 D wear is less in THAs inserted with a REXPOL inlay than a conventional PE inlay after five years. This study confirms, for the first, that the REXPOL HXLPE inlay is preferred to standard PE.  相似文献   
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