Comparative Histological and Morphometric Autopsy Study of Femora and Acetabula with Stable Cemented Hip Prostheses

2003 ◽  
Vol 13 (2) ◽  
pp. 86-93 ◽  
Author(s):  
I. Bos

To gain insight into the tissue reactions leading to non-infectious prosthesis loosening autopsy specimens of 9 stable cemented femoral and acetabular components 1 to 16 years in situ were analysed histomorphologically and morphometrically. In femora and acetabula, bone and cement were separated by an interface membrane composed of connective tissue and granulation tissue after short implant duration. After longer implant duration, infiltrates of macrophages containing wear particles of the bone cement and – though less abundant – polyethylene predominated. The interface membranes of the acetabula appeared three times as broad as in proximal parts of the femora. They showed no topographical variations. In the femora, however, the membranes were proximally considerably thicker than in distal parts. In both femora and acetabula, the adjacent spongiosa were infiltrated by macrophages as well. The cancellous bone showed remodelling with formation of a neocortical layer at the border between the spongiosa and the interface membrane. Focal metaplastic formation of cartilage was also present. The results indicate that in femora and acetabula, basically analogous mechanisms lead to non-infectious late loosening, which is connected with the accumulation of wear particles and macrophages in the interface membrane. A positive correlation of the width of the interface membrane with the implant duration was found only in the acetabulum. This could explain the comparatively frequent socket loosening.

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 738
Author(s):  
Nicola Rossi ◽  
Mario Bačić ◽  
Meho Saša Kovačević ◽  
Lovorka Librić

The design code Eurocode 7 relies on semi-probabilistic calculation procedures, through utilization of the soil parameters obtained by in situ and laboratory tests, or by the means of transformation models. To reach a prescribed safety margin, the inherent soil parameter variability is accounted for through the application of partial factors to either soil parameters directly or to the resistance. However, considering several sources of geotechnical uncertainty, including the inherent soil variability, measurement error and transformation uncertainty, full probabilistic analyses should be implemented to directly consider the site-specific variability. This paper presents the procedure of developing fragility curves for levee slope stability and piping as failure mechanisms that lead to larger breaches, where a direct influence of the flood event intensity on the probability of failure is calculated. A range of fragility curve sets is presented, considering the variability of levee material properties and varying durations of the flood event, thus providing crucial insight into the vulnerability of the levee exposed to rising water levels. The procedure is applied to the River Drava levee, a site which has shown a continuous trend of increased water levels in recent years.


2021 ◽  
Vol 9 (1) ◽  
pp. 104889
Author(s):  
Wyllamanney da S. Pereira ◽  
Fabrício B. Destro ◽  
Cipriano B. Gozzo ◽  
Edson R. Leite ◽  
Júlio C. Sczancoski

2020 ◽  
Vol 4 (04) ◽  
pp. 155-157
Author(s):  
Michael Newman ◽  
David Hartwright

AbstractThe aim of this study was to assess a large, single-surgeon dataset of uncemented total hip arthroplasties that had been templated using software. This assessment compared preoperative templated predictions with what was implanted with regard to (1) femoral prosthesis size and (2) acetabular cup size. The operation notes for two types of uncemented total hip arthroplasty performed by a single surgeon between January 9, 2008, and March 21, 2019, were assessed. The data were refined so that only those that were fully templated on a correctly calibrated pelvic radiograph were included. This provided a total of 153 cases. The predicted software template was compared with actual implanted component sizes. With regard to the femoral stems, the templating software was exactly correct in 45.75% of cases and was accurate to within one size in 87.59% of cases. With regard to the acetabular component, the templating software was exactly correct in 52.94% of cases and was accurate to within one size (2 mm) in 86.94% of cases. Templating software offers an accurate prediction of the size of uncemented femoral and acetabular components. In addition, the benefits of templating include cognitive rehearsal, insight into potentially challenging aspects of surgery, and highlighting intraoperative issues where there is a large intraoperative deviation from what is templated. This study demonstrates the congruence and reproducibility of templating software when compared with other smaller studies performed in the literature.


2021 ◽  
Vol 5 (7) ◽  
pp. 2055-2064
Author(s):  
Saheli Biswas ◽  
Aniruddha P. Kulkarni ◽  
Daniel Fini ◽  
Sarbjit Giddey ◽  
Sankar Bhattacharya

In situ synthesis of methane in a single-temperature zone SOEC in the absence of any methanation catalyst is a completely electrochemical phenomenon governed by the thermodynamic equilibrium of various reactions.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Won Jin Ho ◽  
Rossin Erbe ◽  
Ludmila Danilova ◽  
Zaw Phyo ◽  
Emma Bigelow ◽  
...  

Abstract Background The majority of pancreatic ductal adenocarcinomas (PDAC) are diagnosed at the metastatic stage, and standard therapies have limited activity with a dismal 5-year survival rate of only 8%. The liver and lung are the most common sites of PDAC metastasis, and each have been differentially associated with prognoses and responses to systemic therapies. A deeper understanding of the molecular and cellular landscape within the tumor microenvironment (TME) metastasis at these different sites is critical to informing future therapeutic strategies against metastatic PDAC. Results By leveraging combined mass cytometry, immunohistochemistry, and RNA sequencing, we identify key regulatory pathways that distinguish the liver and lung TMEs in a preclinical mouse model of metastatic PDAC. We demonstrate that the lung TME generally exhibits higher levels of immune infiltration, immune activation, and pro-immune signaling pathways, whereas multiple immune-suppressive pathways are emphasized in the liver TME. We then perform further validation of these preclinical findings in paired human lung and liver metastatic samples using immunohistochemistry from PDAC rapid autopsy specimens. Finally, in silico validation with transfer learning between our mouse model and TCGA datasets further demonstrates that many of the site-associated features are detectable even in the context of different primary tumors. Conclusions Determining the distinctive immune-suppressive features in multiple liver and lung TME datasets provides further insight into the tissue specificity of molecular and cellular pathways, suggesting a potential mechanism underlying the discordant clinical responses that are often observed in metastatic diseases.


2021 ◽  
pp. 109352662110301
Author(s):  
Heather Rytting ◽  
Zachary J Dureau ◽  
Jose Velazquez Vega ◽  
Beverly B Rogers ◽  
Hong Yin

Background Absent submucosal ganglion cells in biopsies 1-3 cm above the pectinate line establishes the pathologic diagnosis of Hirschsprung Disease (HD). Calretinin stains both ganglion cells and their mucosal neurites and has gained importance in HD diagnosis. Absent calretinin positive mucosal neurites in biopsies at the appropriate level above the pectinate line is highly specific for HD. Whether this applies to lower biopsies is uncertain. To address this, we studied anorectal canal autopsy specimens from infants. Methods We performed an autopsy study of infant anorectal canal specimens to describe calretinin staining in this region. Calretinin staining was correlated with histologic and gross landmarks. Results In all 15 non-HD specimens, calretinin positive mucosal neurites were present in glandular mucosa up to the anorectal line where neurites rapidly diminished. Age range was preterm 26 weeks to 3 months. Conclusions Calretinin positive mucosal neurites are present in glandular mucosa up to the anorectal line in young infants. This is potentially important regarding neonatal HD biopsy level and diagnosis. Positive calretinin staining at the anorectal line favors normal innervation making HD unlikely. Absent calretinin positive neurites in glandular mucosa is worrisome for HD in young infants, regardless of location.


Nanoscale ◽  
2015 ◽  
Vol 7 (40) ◽  
pp. 16952-16959 ◽  
Author(s):  
Kaige Zhang ◽  
Gongke Li ◽  
Yuling Hu

The surface-enhanced Raman spectroscopy (SERS) technique is of great importance for insight into the transient reaction intermediates and mechanistic pathways involved in heterogeneously catalyzed chemical reactions under actual reaction conditions, especially in water.


2017 ◽  
Vol 132 ◽  
pp. 17-21 ◽  
Author(s):  
Tarlan Hajilou ◽  
Yun Deng ◽  
Bjørn Rune Rogne ◽  
Nousha Kheradmand ◽  
Afrooz Barnoush
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