Phenotypic and functional characterisation of synovial fluid-derived neutrophils in knee osteoarthritis and knee infection.

OBJECTIVE: An increase in the number of neutrophils (NEUs) has long been associated with infections in the knee joints; however, their impact on knee osteoarthritis (KOA) pathophysiology remains largely unexplored. DESIGN: This study compared the phenotypic and functional characteristics of synovial fluid (SF)-derived NEUs in KOA and knee infection (INF). RESULTS: KOA NEUs were characterised by a lower expression of CD11b, CD54, and CD64 and higher expression of CD62L, TLR2, and TLR4 compared with INF NEUs. Except for CCL2, lower levels of inflammatory mediators and proteases were detected in KOA SF than in INF SF. Functionally, KOA NEUs displayed increased reactive oxygen species production and phagocytic activity compared with INF NEUs. Moreover, KOA and INF NEUs differed in cell sizes, histological characteristics of the surrounding synovial tissues, and their effects on the endothelial cells assessed by human umbilical vein endothelial cells. When KOA patients were subdivided based on the SF NEU abundance, patients with high NEUs (10%-60%) were characterised by i) elevated SF protein levels of TNF-α, IL-1RA, MMP-9, sTREM-1, VILIP-1 and ii) lower CD54, CD64, TLR2 and TLR4 expression compared to patients with low NEUs (<10%). Analysis of paired SF samples suggests that low or high NEU percentages, respectively, persist throughout the course of disease. CONCLUSIONS: Our findings suggest that NEU may play a significant role in KOA pathophysiology. Further studies should explore the mechanisms that contribute to the increased number of NEUs in SF and the clinical consequences of neutrophilic phenotype in KOA.

Analysis of CD40 expression in breast cancer and its relation to clinicopathological characteristics.

Breast cancer is currently the most common cancer in women worldwide. For this reason, new biomarkers for better predicting response to treatment are needed. CD40, described as expressed in haematological and epithelial tumors, is linked to apoptosis and offers promise as a new predictive/ prognostic marker. We evaluated CD40 expression in formalin-fixed, paraffin-embedded samples from 181 breast carcinomas using immunohistochemical staining with CD40 antibody. Samples were divided according to hormone (oestrogen receptor /ER/, progesterone receptor /PR/) and her-2/neu status into groups: 1.Luminal A (ER+PR+her-2/neu-), 2. Luminal B (ER+PR+her-2/neu+), 3.Triple-negative (ER-PR-her-2/neu-) and 4. Her-2/neu (ER-PR-her-2/neu+). The results of CD40 staining were correlated with clinicopathological data. CD40 was found to be expressed in membrane, cytoplasm and nucleus. Normal ducts expressed cytoplasmic CD40 in 30% of cases, in breast tumor ducts in 53% of cases. CD40 was evaluated as an independent marker and significant positive correlation was found with Bcl-2 (p =0.002), early stage (p =0.016) and preoperative chemotherapy (p =0.043). There was higher overall survival for patients with cytoplasmic CD40 expression (0.05). Differences in expression of cytoplasmic CD40 between groups with different hormonal and her-2/neu status were statistically highly significant (p=0.00003). In groups with different hormonal status, a positive statistical correlation was found for the luminal A group with relapse (p=0.024) and stage (p=0.006). No correlation was found with age, disease onset, family history of cancer/ breast cancer, patient history, hormonal replacement therapy, menopausal status at onset of disease, adjuvant chemotherapeutic treatment or disease free survival. Nuclear expression of CD40 was found to be unrelated to any clinicopathological data. However, there was higher ratio of positive cases in cancer cases (83%) than in normal tissue (30%). In conclusion, cytoplasmic expression of CD40 is related to factors connected to better prognosis and suggest that CD40 may have potential as a new prognostic factor in breast cancer.

Hypokalemia-induced ultrastructural, histochemical and connexin-43 alterations resulting in atrial and ventricular fibrillations.

Perfusion of the isolated guinea pig heart with hypokalemic solution provide simple model for examination of the molecular mechanisms involved in the incidence of atrial and/or ventricular fibrillations. The results point out that dispersion of the metabolic and subcellular alterations and heterogenously impaired intercellular coupling might account for electrical disturbances and desynchronization of the myocardium thus facilitate occurrence of fibrillation.