Aneurysmal 99m Tc-HMPAO Uptake in Brain Death.

ABSTRACT: A 41-year-old man was admitted to hospital due to sudden loss of consciousness. A regional brain perfusion SPECT/low-dose CT showed abnormal 99m Tc-HMPAO uptake in the right hemisphere frontotemporally without any other supratentorial or infratentorial radiotracer uptake. A neuropathological examination disclosed a middle cerebral artery aneurysm. Presumably, vessel wall fibrosis prevented collapse. Multiple transmural dissections of the fibrotic aneurysmal wall were the source of the subarachnoid hemorrhage. This interesting image shows that radiotracer accumulation in cerebral artery aneurysms can be a diagnostic pitfall in brain death scintigraphy assessment.

Proteinase-activated Receptor 2: Springboard of Tumors.

Proteinase-activated receptors (PARs) were discovered more than 25 years ago and since then, their role in cancer has been under investigation. Research has primarily focused on the receptors located on the membrane of cancer cells and their impact on metabolism, intracellular signalling, and proliferation. Regarding the host response to cancer, studies have predominantly examined the relationship of thrombin receptors (PAR-1, PAR-3, and PAR-4) with blood clotting in distant metastatic spread. However, limited studies have examined the role of PARs, especially PAR-2, in the host anti-tumor immunity. This review article provides insights into the role of PAR-2 on cancer cells and immune competent cells involved in cancer development and progression. It also discussed the current knowledge of the importance of PAR-2 activation at various stages of cancer progression and its association with cancer-related pain.

Potential novel markers in IBD and CRC diagnostics. Are MMP-19 and RAGE promising candidates?

AIMS: Inflammatory bowel diseases and colorectal cancer are serious intestinal disorders with continuously increasing incidence. Many aspects of etiopathogenesis still remain unclear. There is an urgent need to improve early diagnostics and markers indicating the progression of the disease. The aim of our study was to analyze the expression of matrix metalloproteinase-19 (MMP-19), and the receptor for advanced glycation end-products (RAGE) in different cell subpopulations in inflammatory bowel diseases (IBD) and colorectal cancer (CRC) compared to the tissue in the vicinity of pathological processes. METHODS: Expression of both markers in epithelium, macrophages and vessels were evaluated in IBD and CRC groups. They were detected using immunohistochemistry in paraffin sections. RESULTS: There were significant differences between the expression of MMP-19 on macrophages and vessels among healthy and cancer tissues. In both, macrophages and vessels were significantly lower levels in cancer tissues. The expression of MMP-19 on vessels was also significantly different between peritumoral and cancer tissues (higher levels in peritumoral tissue). RAGE expression in macrophages was significantly different between healthy and cancer tissues and between peritumoral and cancer tissues. There was significantly lower expression in cancer tissues than in healthy and peritumoral tissues. Expression of RAGE in vessels was significantly different just in the comparison of healthy and peritumoral tissues (higher levels in healthy tissues). CONCLUSION: Both markers seem to be promising potential auxiliary markers in IBD and CRC diagnostics. They can also improve evaluation of disease progression.