Project description:Host defense against infection is based on two crucial mechanisms: the inflammatory response and the activation of coagulation. Platelets are involved in both hemostasis and immune response. These mechanisms work together in a complex and synchronous manner making the contribution of platelets of major importance in sepsis. This is a summary of the pathophysiology of sepsis-induced thrombocytopenia, microvascular consequences, platelet-endothelial cells and platelet-pathogens interactions. The critical role of platelets during sepsis and the therapeutic implications are also reviewed.
Project description:Interstitial fibrosis represents the final common pathway of any form of progressive renal disease. The severity of tubular interstitial damage is highly correlated to the degree of decline of renal function, even better than the glomerular lesions do. Angiotensin II (Ang II), the main effector of the renin-angiotensin system, is a critical promoter of fibrogenesis. It represents a nexus among glomerular capillary hypertension, barrier dysfunction, and renal tubular injury caused by abnormally filtered proteins. Transforming growth factor (TGF)-β1 and reactive oxygen species (ROS) are the key mediators of the pro-fibrotic effect of Ang II causing apoptosis and epithelial-to-mesenchymal transition of the renal tubular epithelium. Recent studies link fibrosis to changes of microRNA (miRNA) modulated by Ang II through TGF-β1, unraveling that antifibrotic action of Ang II antagonism is attributable to epigenetic control of fibrosis-associated genes. Other mechanisms of Ang II-induced fibrosis include ROS-dependent activation of hypoxia-inducible factor-1. Finally, Ang II via angiotensin type 1 receptor regulates the activation and transdifferentiation of pericytes and fibrocytes into scar-forming myofibroblasts. Detachment and phenotypic changes of the former can lead to the loss of peritubular capillaries and also contribute to hypoxia-dependent fibrosis.
Project description:Liver cancer represents a major health problem worldwide with growing incidence and high mortality, hepatocellular carcinoma (HCC) being the most frequent. Hepatocytes are likely the cellular origin of most HCCs through the accumulation of genetic alterations, although hepatic progenitor cells (HPCs) might also be candidates in specific cases, as discussed here. HCC usually develops in a context of chronic inflammation, fibrosis, and cirrhosis, although the role of fibrosis is controversial. The interplay between hepatocytes, immune cells and hepatic stellate cells is a key issue. This review summarizes critical aspects of the liver tumor microenvironment paying special attention to platelets as new key players, which exert both pro- and anti-tumor effects, determined by specific contexts and a tight regulation of platelet signaling. Additionally, the relevance of specific signaling pathways, mainly HGF/MET, EGFR and TGF-β is discussed. HGF and TGF-β are produced by different liver cells and platelets and regulate not only tumor cell fate but also HPCs, inflammation and fibrosis, these being key players in these processes. The role of C3G/RAPGEF1, required for the proper function of HGF/MET signaling in HCC and HPCs, is highlighted, due to its ability to promote HCC growth and, regulate HPC fate and platelet-mediated actions on liver cancer.
Project description:Subcapital femoral neck fractures are associated with high morbidity and mortality. These fractures mostly occur as a result of a high-force impact from traffic accidents and a fall from a great height, though non-traumatic forms are described in transient osteoporosis during the second half of pregnancy, in convulsions during electric shock, eclampsia, hypocalcemia, osteomalacia, renal osteodystrophy and myeloma.In this report we present a bilateral subcapital femoral neck fracture in a woman sustained two days after delivery. The right hip fracture was treated with fixation using three spongious screws without capsular decompression, while for the left hip a capsular decompression by open reduction and fixation was performed. Physical treatment based on active and passive movements was immediately initiated. The patient was able to rest upon her right leg within seven and upon the left leg within eight months. X-Rays showed the accurate position of fragments and implants throughout the recovery period. Twelve years later, the patient made a full recovery and the x-rays showed that both femoral heads are vital and fully recovered.Early anatomical reconstruction followed by internal fixation is crucial in the prevention of long-term complications. Complications of internal fixations include non-union (10-30%), avascular necrosis (15-33%), deep vein thrombosis and pulmonary embolism.
Project description:Thrombus components are dynamically influenced by local blood flow and blood immune cells. After a large-vessel occlusion stroke, changes in the cerebral thrombus are unclear. Here we assessed a total of 206 cerebral thrombi from patients with ischemic stroke undergoing endovascular thrombectomy. The thrombi were categorized by time to reperfusion of <4 h (T4), 4-8 h (T4-8), and >8 h (T8). The cellular compositions in thrombus were analyzed, and relevant clinical features were compared. Both white blood cells and neutrophils were increased and then decreased in thrombus with time to reperfusion, which were positively correlated with those in peripheral blood. The neutrophil extracellular trap (NET) content in thrombus was correlated with the degree of neurological impairment of patients. Moreover, with prolonged time to reperfusion, the patients showed a trend of better collateral grade, which was associated with a lower NET content in the thrombus. In conclusion, the present results reveal the relationship between time-related endovascular immune response and clinical symptoms post-stroke from the perspective of thrombus and peripheral blood. The time-related pathological changes of cerebral thrombus may not be the direct cause for the difficulty in thrombolysis and thrombectomy. A low NET content in thrombi indicates excellent collateral flow, which suggests that treatments targeting NETs in thrombi might be beneficial for early neurological protection.
Project description:We present the case of an apparently healthy 31-year-old man with malignant progression of coronary artery disease and recurrent angina resulting from suspected large vessel vasculitis. This case highlights the importance of considering vasculitis in patients without atherosclerotic risk factors, using a multidisciplinary team approach, and suppressing inflammation before coronary revascularization to improve outcomes. (Level of Difficulty: Beginner.).
Project description:In this study, two gene expression analyses were performed. The first analysis, comparing the DEGs between fibrotic and non-fibrotic tissue, revealed genes which may play a role in testicular fibrosis, including VCAM1. In addition, this analysis revealed a pertinent role for genes involved in the TGF-β1 pathway. Secondly, a differential gene expression analysis between KS and TA samples was performed. GO analysis revealed genes involved in the chronic inflammatory responses. When comparing the X-linked genes of the first analysis (fibrotic versus non-fibrotic) with those of the second analysis (KS versus TA), X-linked fibrotic genes involved in KS revealed, i.e. MXRA5, DCX and VCX3B. Their potential role in KS-related testicular fibrosis needs further study.
Project description:Congenital left atrial appendage aneurysm is very rare. We describe a giant left atrial appendage aneurysm with a pinball-like mobile thrombus in a 2-year-old child with cardioembolic stroke. Patient underwent successful surgical resection of the aneurysm.