Genome-wide transcriptome induced in osteoclast-like cells differentiated on three different hard tissues

Hard tissue resorption is a multistep process, which requires a complex interaction between multinucleated clast cells and the hard tissues to be resorbed. This process is regulated by genetic factors and inflammatory cytokines. This study was directed toward the clast cells to clarify the ability of these cells to distinguish between the resorbed substrates and the possible influence of the resorbed tissues on the intracellular mechanism behind the resorption process. To study the influence of the mineralized tissues on the differentiation and activity of the clast cells, macrophage cells were cultured on powder substrates made from bone, dentine and cementum tissues. After cell differentiation, ribonucleic acid was isolated and gene expression induced by the three hard tissues was analyzed based on RNA-Sequencing. The results showed many differentially expressed gene between the samples of the study.1930 genes were significantly differentially regulated on cementum compared with the cells stimulated on glass, 446 between bone tissue and the positive control 87 between dentin and control samples. Moreover, the comparison between the stimulated cells on the hard tissues showed 314 differentially regulated genes between cementum and dentine, 252 between bone and cementum and just one significantly differentially regulated gene between dentine and bone. These results reflect the influence of the hard substrates on the differentiation and activity of osteoclast-like cells. For example, cathepsin k gene was downregulated by 3.2 folds in the bone samples and in the cementum samples by 4.8 folds compared to the cells differentiated on glass but in the dentin groups there wasn’t any significant difference in gene expression. Comparing bone and dentine samples it was upregulated by 3.8 folds in the dentine samples and was downregulated by 1.5 folds in the cementum samples when compared with bone samples. In the comparison between cementum and dentin samples cathepsin k was upregulated in dentine samples by 11.3 folds. Some possible candidates were identified like Inhibitor of differentiation1 gene which was upregulated only in cementum samples in comparison with cells differentiated on glass and upregulated by 3.5 folds in cementum samples compared with bone samples. In comparison with dentin this gene was downregulated in dentin samples by 2.7 folds and didn´t show any significant change between bone and dentin samples. The present study expands our understanding of the interaction between clast cells and mineralized tissues and indicates new possible target genes of relevance for diagnostic and therapeutic strategies

PET/CT Scanner and Bone Marrow Biopsy in Detection of Bone Marrow Involvement in Diffuse Large B-Cell Lymphoma.

Evaluation of bone marrow involvement (BMI) is paramount in diffuse large B-cell lymphoma (DLBCL) for prognostic and therapeutic reasons. PET/CT scanner (PET) is now a routine examination for the staging of DLBCL with prognostic and therapeutic implications. This study evaluates the role of PET for detecting marrow involvement compared to bone marrow biopsy (BMB). This monocentric study included 54 patients diagnosed with DLBCL between 2009 and 2013 and who had FDG PET/CT in a pre-treatment setting. A correlation analysis of the detection of BMI by PET and BMB was performed. A prognostic evaluation of BMI by BMB and/or PET/CT and correlation with an overall 2-year survival were analyzed. PET was more sensitive for the detection of BMI than BMB (92.3% vs. 38.5%). It can be considered a discriminatory Pre-BMB test with a negative predictive value of 97.6%. In addition, BMI by PET had a prognostic value with strong correlation with progression-free survival (PFS) (HR = 3.81; p = 0.013) and overall survival (OS) (HR = 4.12; p = 0.03) while the BMB had not. PET shows superior performance to the BMB for the detection of marrow involvement in DLBCL. It may be considered as the first line examination of bone marrow instead of the biopsy

What Radiologist Should Know about MRI Translational Forces and Hazard: An Ex-Vivo Simulation of Retained Metallic Shrapnel

Background. In a country immersed in endless rounds of wars, retained metallic foreign bodies remain a significant dilemma in the daily practice of every Lebanese radiologist. When a shrapnel’s hazard is of concern, the decision between performing or refusing a justified MRI exam is not always straightforward. In this small trial, we aimed to better understand the shrapnel’s MRI safety by mimicking our daily practice. Methods. Five shrapnel with an incremental increase in their long axis were put in an animal flesh and then introduced into a 3 T magnetic field. The behavior of each shrapnel was concretely assessed by performing before and after magnetic field exposure CT acquisitions. Results. Translation along the z-axis ranged from 0.9 mm to 2.8 mm. Torque angle ranged between 2.8 and 54 degrees with an average of 15.62 degrees. Conclusions. Shrapnel’s movements in the magnetic field are not negligible during the acute phase of injury where there is no reinforcing fibroblastic reaction and invite us to reconsider the MRI safety of these metallic foreign bodies. Standard radiographs may be sufficient, but a targeted CT scan may be of better value for a confident decision for assessment of shrapnel position near viscera and major vessels

It Could Be Worse But It Should Be Better: COVID-19 and The Lebanese Radiology Departments Preparedness.

An unprecedented sanitary challenge is threatening human beings due to COVID-19 pandemic. There is no light at the end of the tunnel concerning treatment and worries from a possible second wave start to arise even before the end of the first one. We conducted a multicenter study to reassess the different aspects of radiology departments’ preparedness in Lebanon stating the points of strength and more importantly depicting the points of weakness. Lessons were then extracted to be more prepared for possible future similar circumstances

Ongoing Epidemic of Cutaneous Leishmaniasis among Syrian Refugees, Lebanon

In September 2012, a cutaneous leishmaniasis outbreak began among Syrian refugees in Lebanon. For 948 patients in whom leishmaniasis was not confirmed, we obtained samples for microscopic confirmation and molecular speciation. We identified Leishmania tropica in 85% and L. major in 15% of patients. After 3 months of megulamine antimonite therapy, patients initial cure rate was 82%

PFS curves.

<p>The PFS curves are provided according to the result of bone marrow involvement (a) BMB results (HR: 0.61 [0.13–2.78]; p = 0.517) (b) PET results (HR: 3.81 [1.23–11.87]; p = 0.013).</p

OS curves.

<p>OS curves are provided according to the result of bone marrow involvement. (a) BMB results (HR: 0.83 [0.10–6.77]; p = 0.864) (b) PET results (HR: 4.12 [1.03–16.5]; p = 0.03).</p