SummaryLeukotriene B 4 (LTB 4 ) is a neutrophil chemotactic molecule with important involvement in the inflammatory responses of chronic obstructive pulmonary disease (COPD). Airway epithelium is emerging as a regulator of innate immune responses to a variety of insults including cigarette smoke, the major risk factor for COPD. In this study we have explored whether cigarette smoke extracts (CSE) or soluble mediators present in distal lung fluid samples (mini-bronchoalveolar lavages) from smokers alter the expression of the LTB 4 receptor 2 (BLT2) and peroxisome proliferator-activated receptor-a (PPAR-a) in bronchial epithelial cells. We also evaluated the effects of CSE on the expression of intercellular adhesion molecule 1 (ICAM-1) and on the binding of signal transducer and activator of transcription 1 (STAT-1) to ICAM-1 promoter as well as the adhesiveness of neutrophils to bronchial epithelial cells. CSE and minibronchoalveolar lavages from smokers increased BLT2 and ICAM-1 expression as well as the adhesiveness of neutrophils to bronchial epithelial cells and decreased PPAR-a expression. CSE induced the activation of STAT-1 and its binding to ICAM-1 promoter. These findings suggest that, in bronchial epithelial cells, CSE promote a prevalent induction of pro-inflammatory BLT2 receptors and activate mechanisms leading to increased neutrophil adhesion, a mechanism that contributes to airway neutrophilia and to tissue damage.

Cyclooxigenase (COX) is the rate-limiting enzyme for the conversion of arachidonic acid (AA) to prostaglandins (PGs). Two isoforms of COX have been identified: COX-1 is constitutively expressed in many cells and is involved in cell homeostasis, angiogenesis and cell-cell signalling; COX-2 is not expressed in normal condition however it is strongly expressed in inflammation. The oral cavity is costantly exposed to physical and chemical trauma that could lead to mucosal reactions such as hyperplasia, dysplasia and cancer. Early diagnosis is the most important issue to address for a positive outcome of oral cancer; therefore it would be useful to identify molecular markers whose expression is associated with the various stages of oral cancer progression. Since COX enzyme has been involved, with different mechanisms, in the development and progression of malignancies we decided to investigate the expression and localization of COX-1 and COX-2 in normal human oral mucosa and three different pathologies (hyperplasia, dysplasia and carcinoma) by immunohistochemistry and RT-PCR. COX-1 mRNA and protein have been detected already in normal oral mucosa and their expression progressively increases from normal samples towards hyperplasia, dysplasia and finally carcinoma. On the contrary, COX-2 is not expressed in the normal tissue, starts to be expressed in hyperplasia, reaches the maximum activation in dysplasia and then starts to be downregulated in carcinoma.

SummaryMany studies have demonstrated the physiological effects of oxytocin (OT), atrial natriuretic peptide (ANP) and vasopressin (VP) in the homoeostasis of body fluids during physical exercise. However, a little information is available about the related immunohistochemical changes in hypothalamic magnocellular neurosecretory system during and after the training. The aim of the present work was to study the immunohistochemical changes in OT, ANP and VP levels in the hypothalamic paraventricular nucleus during and after resistance exercise protocol. Three groups of Wistar rats were trained by a rung ladder protocol for 15, 30 and 45 days, respectively; a fourth group was left to rest for 15 days after the training. Finally, four sedentary groups were used as controls. The results show that resistance training induces a significant reduction in the percentage of OT-positive neurons, compared with sedentary controls. In contrast, this protocol did not induce any change in VP levels, and ANP levels did not change significantly. However, VP increased after the resting period of 15 days. Our work shows that neurons of the paraventricular nucleus are involved in body fluid homoeostasis during and after resistance exercise. The functional significance of these changes in OT and VP levels, during and after the protocol, needs to be further investigated.

In this case of OM in a child, we report lack of recurrence after excision associated with low MMP-2 protein expression and absence of MMP-9. We believe it is worthy to deeply investigate the relationship between MMPs expression and OM behaviour with the aim to use MMPs as prognostic and/or therapeutic markers in OM.

Salivary gland tumors, most of which are rare benign tumors, represent a histologically heterogenous group with the greatest diversity of morphological and cellular features. The aim of this study is to analyse the expression and possible interactions between gelatinases (MMP-2, MMP-9) and cyclooxygenases (COX-1, COX-2) in some benign salivary gland tumors. We investigated the expression of gelatinases and cyclooxigenases in control salivary gland, Pleomorphic adenoma and Warthin's tumor through immunohistochemistry and Reverse Transcription - Polymerase Chain Reaction (PCR). We identified the expression of both classes of enzyme in normal samples and in the two types of pathological samples without any quantitative differences. From the present data no significant differences emerge in the expression of these enzymes among the different pathologies examined. Nevertheless, due to the small number of samples included in this study, general statements regarding correlation between the degree of severity of the tumoral pathology and the quantitative expression of these potential tumoral markers can not be made.