[Interactions between vascular endothelium and immune cells: A key control point of radiation-induced digestive lesions]. / Interactions endothélium vasculaire ­ cellules immunitaires : un point de contrôle clef des lésions digestives radio-induites.

Radiation-induced toxicity of the digestive tract is a major clinical concern as many cancer survivors have received radiotherapy for tumours of the abdominopelvic area. The coordination and orchestration of a tissue's response to stress depend not only on the phenotype of the cells that make up the tissue but also on cell-cell interactions. The digestive system, i.e., the intestine/colon/rectum, is made up of a range of different cell populations: epithelial cells, stromal cells, i.e. endothelial cells and mesenchymal lineages, immune cells and nerve cells. Moreover, each of these populations is heterogeneous and presents very significant plasticity and differentiation states. The pathogenesis of radiation-induced digestive lesions is an integrated process that involves multiple cellular compartments interacting in a complex sequence of events. Understanding all the cellular events and communication networks that contribute to the tissue's response to stress is therefore a major conceptual and methodological scientific challenge. The study of heterogeneous populations of cells in a tissue is now possible thanks to "single cell' RNA sequencing and spatial transcriptomics techniques, which enable a comprehensive study of the transcriptomic profiles of individual cells in an integrated system. In addition, the mathematical and bioinformatics tools that are now available for the large-scale analysis of data allow the inference of cell-cell communication networks. Such approaches have become possible through advances in bioinformatics algorithms for the analysis and deciphering of interaction networks. Interactions influence the tissue regeneration process through expression of various molecules, including metabolites, integrins, junction proteins, ligands, receptors and proteins secreted into the extracellular space. The vascular network is viewed as a key player in the progression of digestive lesions, which are characterised by infiltration of a range of immune cells. A better characterisation of endothelium/immune cell interactions in suitable preclinical models, as well as in humans, may help to identify some promising therapeutic targets for the prediction, prevention or treatment of digestive toxicity after radiotherapy.

The role of the intensive care unit in real-time surveillance of emerging pandemics: the Italian GiViTI experience.

The prompt availability of reliable epidemiological information on emerging pandemics is crucial for public health policy-makers. Early in 2013, a possible new H1N1 epidemic notified by an intensive care unit (ICU) to GiViTI, the Italian ICU network, prompted the re-activation of the real-time monitoring system developed during the 2009-2010 pandemic. Based on data from 216 ICUs, we were able to detect and monitor an outbreak of severe H1N1 infection, and to compare the situation with previous years. The timely and correct assessment of the severity of an epidemic can be obtained by investigating ICU admissions, especially when historical comparisons can be made.

Redistribution of the nuclear protein IFI16 into the cytoplasm of ultraviolet B-exposed keratinocytes as a mechanism of autoantigen processing.

BACKGROUND: The skin has long been recognized as a prominent target tissue in systemic lupus erythematosus (SLE) which plays a crucial role in the initiation and perpetuation of the autoimmune reaction cascade as a consequence of ultraviolet (UV)-induced keratinocyte apoptosis. Antibodies against IFI16 (interferon-inducible protein 16) have been detected in the sera of patients with SLE. OBJECTIVES: To verify whether the induction of autoimmunity against IFI16 involves redistribution of this nuclear protein in keratinocytes during UVB-induced cell death. METHODS: An in vitro epidermal model was developed to investigate the fate of the IFI16 protein in keratinocytes after irradiation with UVB; both keratinocyte monolayers and human skin explants were used. IFI16 expression and localization were also analysed in diseased skin sections of patients with SLE. RESULTS: We demonstrated that IFI16, normally restricted to the nucleus, can be induced to appear in the cytoplasm under conditions of UVB-induced cell injury. This nucleus to cytoplasm translocation was also observed in skin explants exposed to UVB and in the diseased skin sections from patients with SLE. In addition, IFI16 was found in the supernatants of UVB-exposed keratinocytes. CONCLUSIONS: The finding that IFI16 is present in the cytoplasm of diseased skin cells from patients with SLE and the demonstration of IFI16 in the supernatants of UVB-exposed keratinocytes, suggest that UVB irradiation or other stimuli may favour an abnormal IFI16 presentation to the afferent limb of the immune system and potentially an autoimmune response against the protein itself.

New cell-based indicator assays for the detection of human cytomegalovirus infection and screening of inhibitors of viral immediate-early 2 protein activity.

AIMS: Expression of early (E) genes of human cytomegalovirus (HCMV) is stimulated cooperatively by the activities of host cell transcription factors and the viral immediate-early 2 (IE2) protein. Taking advantage of the IE2-dependent inducibility of E gene promoters, in this study, we generated cell-based assays in which the expression of the enhanced green fluorescence protein (EGFP) reporter gene was driven by the UL54 or UL112/113 E promoters. METHODS AND RESULTS: Cell clones derived from a stably transfected human cell line permissive to HCMV replication showed a specific and inducible dose- and time-dependent EGFP response to HCMV infection. The sensitivity of these indicator cells for detecting infectious particles of clinical isolates of HCMV was comparable to that of a conventional plaque assay. The HCMV-induced EGFP expression was completely prevented by treatment of indicator cells with fomivirsen, an antisense oligodeoxynucleotide designed to block IE2 expression, and this inhibitory activity was also observed when the IE2 protein alone was constitutively expressed in EGFP indicator cells. CONCLUSIONS: The EGFP-based cell assays have proved to be a rapid, sensitive, quantitative and specific system for detection of HCMV and selection of antivirals. SIGNIFICANCE AND IMPACT OF THE STUDY: These new cell-based assays can be exploited as functional assays to detect infectious HCMV particles, as well as to screen antiviral compounds that interfere with IE2 activity.

Role of soluble and cell surface molecules in the pathogenesis of autoimmune skin diseases.

The skin is one of the most commonly involved tissue in rheumatic autoimmune diseases. Different mechanisms are thought to be implicated in the pathogenesis of skin lesions. In genetically predisposed individuals, ultraviolet (UV) light can contribute to the induction of skin lesions via an inflammatory process. UV light promotes the release of cytokines by keratinocytes and the induction of adhesion molecules on the surface of epidermal cells initiating a cascade of inflammatory events and recruiting immunoinflammatory cells into the skin. In this review data regarding the expression of TNF-alpha in lesional skin tissue from subacute cutaneous lupus erythematosus patients and the role of interferons in the pathogenesis of skin manifestations of rheumatic autoimmune diseases are reported. In addition, an overview on the expression of cellular adhesion molecules in these diseases is provided.UV light can also induce apoptosis in keratinocytes. During this cell death several enzymes became activated. Among them, desoxyribonuclease (DNase) is an enzyme involved in degrading DNA during apoptosis. Data regarding the activity of DNAse in patients with cutaneous lupus erythematosus as a possible risk factor for the development of systemic disease are here reported.

[Bronchial fistula postpneumonectomy: predictive factors]. / Fistule bronchiques postpneumonectomies: facteurs prédictifs.

OBJECTIVE: To determine predictive factors of bronchial fistula following pneumonectomy. PATIENTS AND METHODS: In 14 years (1989-2003), we collect 58 cases of bronchial fistula following 725 consecutive pneumonectomy in the service of thoracic surgery of the Sainte Marguerite Hospital in Marseilles. There were 53 cases (91.4%) of cancers and 5 cases (8.6%) of various pathology. The average age of the patients was of 61 +/- 10 years (range 24 to 80 years). The sex ratio M/F was 8.7. The software of regression SPSS (version11.5) was used to identify the factors risk of a bronchial fistula after a univariate and multivariate analysis. RESULTS: The prevalence of the bronchial fistula after a pneumonectomy was 8%.The preoperative factors which increased to a significant degree the incidence of the bronchial dent to the univariate analysis were the chronic smoking (P < 0.001), the existence of COPD (P = 0.001) and of a previous thoracic surgery (P = 0.01). Operational data like a right- side pulmonary resection (P < 0.001), the type of bronchial stup carried out (P = 0.03) as and an extended pneumonectomy to the auricule (P = 0.03) were significant risk factors. With the logistic regression the significant risk factors were the chronic smoking (P = 0.002), the existence of COPD (P = 0.003), a previous pulmonary surgery (P = 0.03) and the right - side of the pneumonectomy (P < 0.001). The indication of the pneumonectomy was retained neither by the univariate analysis, nor by the logistic regression significant risk factors. CONCLUSION: The predictive factors of a bronchial fistula after a pneumonectomy are dominated by respiratory co-morbidities. To prevent this complication, we insist on the stop of the tobacco, a better respiratory preparation and the acquisition of a protocol adapted of the bronchial stub after a pneumonectomy particularly on the right side.

Dehiscences of the bronchial joining after pneumonectomy for cancers: Incidence, gravity and risk factor.

Objectives To assess the incidence, severity and risk factors of bronchial fistula following pneumonectomy for cancer. Patients and methods From 1989 to 2003, 690 consecutive patients underwent a pneumonectomy for thoracic cancer in Sercive of Thoracic Surgery of the Teaching Hospital of Sainte Marguerite in Marseilles (France). The M/F sex ratio was 5,44 . Mean age was 59+/-9,9 years [16 - 81]. Clinical and surgical variables were studied retrospectively, and their possible association with the occurrence of a bronchial fistula was assessed by univariate and multivariate analysis. Results Fifty one patients (7,7%) experienced a bronchial fistula. This complication accounted for 56% (45/80) of the cases of reoperation and 25,5% (13/51) of early deaths. At univariate analysis, the following factors were identified as statistically significant: tobacco consumption (p<0,003), presence of COPD (p =0,02), preoperative radiotherapy (p=0,03), previous thoracic surgery (p=0,03), right side of the resection (p<0,001), hand-fashioned bronchial suture (p=0,05) and squamous cell histology (p= 0,04). Multivariate logistic regression analysis disclosed tobacco consumption (p=0,002), presence of COPD (p=0,01), previous thoracic surgery (p=0,03), extended procedures (p=0,05), right pneumonectomy (p<0,001) and squamous cell histology (p=0,02) as independent predictors of bronchial fistula. Conclusion The occurrence of a bronchial fistula following pneumonectomy is a frequent life threatening event, especially in cases of right sided resections and extended procedures. Tobacco cessation, preoperative rehabilitation, and reinforcement of the bronchial suture are possible means of prevention.

Altered patterns of the interferon-inducible gene IFI16 expression in head and neck squamous cell carcinoma: immunohistochemical study including correlation with retinoblastoma protein, human papillomavirus infection and proliferation index.

AIMS: To investigate whether the expression of interferon (IFN)-inducible gene IFI16 is inversely related to proliferative activity in vivo, we compared immunohistochemical reactivity of IFI16 in a series of head and neck squamous cell carcinomas (HNSCCs) with their proliferation index and the cell cycle regulator pRb. As human papillomavirus (HPV) infection is manifested by changes in the function or expression level of host genes such as IFN-inducible genes, we also investigated the presence of HPV DNA to determine whether head and neck cancers associated with HPV DNA can be distinguished from tumours that are presumably transformed by other mechanisms. METHODS: Thirty-six HNSCCs were evaluated for IFI16, pRb and Ki67 expression by immunohistochemistry. The presence of HPV was also detected by polymerase chain reaction. Nine tumours were located in the oropharynx (tonsillar area) and 27 in the larynx. RESULTS: HPV DNA was found in 14 of 25 (56%) laryngeal SCCs and in five of nine (56%) tonsillar SCC specimens examined; 17 out of the 19 HPV-DNA-positive cases showed high-grade IFI16 expression. Overall, proliferative activity was significantly related to tumour differentiation and histological grading. IFI16 protein expression was significantly inversely correlated with Ki67 (P = 0.039). Low-proliferating tumours positive for IFI16 staining showed a marked expression of pRb and a better prognosis than those whose tumours had low IFI16, pRb levels and a high proliferation index. CONCLUSIONS: To our knowledge, this is the first expression analysis of the IFN-inducible IFI16 gene in HNSCC. Low-proliferating tumours positive for IFI16 staining showed a marked expression of pRb and a better prognosis than those whose tumours had low IFI16, pRb levels and a high proliferation index.

Irreversible H2-antagonism of the four isomeric butyl analogues of mifentidine.

It has been hypothesized that bidentate hydrogen bonding plays an important role in the interaction of imidazolylphenylformamidines with the H2-receptor. The present study, in which the degree of pseudo-irreversible H2-antagonism of the four isomeric butyl substituted mifentidine analogues was determined on the spontaneously beating right atrium of the male guinea-pig, lends further support to this hypothesis. In solution the EE/EZ ratio is different for the four isomeric butylated mifentidine analogues. The rank order of the percentage of E,E conformation, which favors a bidentate interaction, of the formamidine moiety parallels the rank order of pseudo-irreversible H2-antagonism.