Thigh muscles injuries in professional soccer players: a one year longitudinal study

Thigh muscles indirect injuries are common finding in soccer and represent a critical challenge for teams medical staffs. Indirect injuries are classified on the basis of their site and their clinical and radiological findings, but the assessment of a precise prognosis remains a crucial point. Both ultrasound (US) and magnetic resonance (MR) represent effective techniques not only to detect indirect injuries but also to accurately determine severity, location, and, consequently, the prognosis. In this setting, our aim is to review imaging findings of professional athletes muscle tears at three time points (3 days, 2 weeks, and 4 weeks after the time of injury) and, further, to investigate the correlation between tears extent and lay-off time of the athletes. Combined US-MR assessment could be helpful in the management of thigh muscles indirect injuries providing accurate information about the site, the extent, and the healing proces

Vav1

Common variable immunodeficiency (CVID) is a primary immune disorder characterized by impaired antibody production, which is in many instances secondary to defective T cell function (T-CVID). We previously identified a subset of T-CVID patients characterized by defective expression of Vav1, a guanine nucleotide exchanger which couples the T-cell antigen receptor to reorganization of the actin cytoskeleton. Here we have addressed the possibility that an intrinsic defect in the Vav1 gene might underlie the reduction in Vav protein observed in T cells from these patients. We report the identification in one T-CVID patient of a heterozygous deletion in Vav1. The gene deletion, spanning exons 2–27, accounts for the reduction in Vav1 mRNA and protein in T cells from this patient. The disease-related pedigree of this patient suggests a de novo origin of the Vav1 deletion. The findings highlights Vav1 as an autosomal dominant disease gene associated with CVID with defective T-cell function

The Helicobacter pylori vacuolating toxin inhibits T-cell activation by two independent mechanisms

Helicobacter pylori toxin, VacA, damages the gastric epithelium by erosion and loosening of tight junctions. Here we report that VacA also interferes with T cell activation by two different mechanisms. Formation of anion-specific channels by VacA prevents calcium influx from the extracellular milieu. The transcription factor NF-AT thus fails to translocate to the nucleus and activate key cytokine genes. A second, channel-independent mechanism involves activation of intracellular signaling through the mitogen-activated protein kinases MKK3/6 and p38 and the Rac-specific nucleotide exchange factor, Vav. As a consequence of aberrant Rac activation, disordered actin polymerization is stimulated. The resulting defects in T cell activation may help H. pylori to prevent an effective immune response leading to chronic colonization of its gastric niche. Key words: MAP kinase signaling cascades • immunosuppression • host–pathogen interactions • calcium signalin

Human gastric epithelium produces IL-4 and IL-4delta2 isoform only upon Helicobacter pylori infection.

Recent evidence suggests that interleukin-4 (IL-4) is related to mucosal tolerance by which an injurious immune response is prevented, suppressed or shifted to a non-injurious response. We investigated the expression of IL-4 and its splice variant isoform IL-4δ2 in gastric epithelial cells of healthy subjects and gastritis patients infected with Helicobacter pylori (H. pylori) with or without the cag pathogenicity island ( cag-PAI). IL-4 and IL-4δ2 mRNAs were evaluated in microdissected gastric epithelium and in AGS cell lines co-cultured with H. pylori B128 or SSI strains. IL-4 mRNA was consistently detected in microdissected gastric epithelial cells from healthy subjects. The IL-4 mRNA expression was low in H. pylori-infected patients, and markedly reduced in cag-PAI-positive ones. IL-4δ2 mRNA was expressed on gastric epithelium of H. pylori-infected patients, but not in healthy subjects. The IL-452 expression was lower in cag-PAI-positive than in cag-PAI-negative H. pylori infected patients. AGS cells also produced IL-4 mRNA upon SSI strain stimulation, whereas IL-4δ2 mRNA expression was detected in AGS co-cultured with either SSI or B128 strains. An inverse correlation was documented between IL-4 and IL-482 mRNA expression by microdissected gastric epithelial cells and the score of gastritis. IL-4, but not IL-452, is expressed by gastric epithelium of healthy subjects, whereas IL-452 and lesser IL-4 mRNA are detectable in the gastric epithelium of H. pylori-infected patients. Data suggest that gastric epithelial cells might regulate the balance between tolerance and immune response by the fine tuning of IL-4 and IL-4δ2 expression

Chlamydophila pneumoniae phospholipase D (CpPLD) drives Th17 inflammation in human atherosclerosis

Phospholipases are produced from bacterial pathogens causing very different diseases. One of the most intriguing aspects of phospholipases is their potential to interfere with cellular signaling cascades and to modulate the host-immune response. Here, we investigated the role of the innate and acquired immune responses elicited by Chlamydophila pneumoniae phospholipase D (CpPLD) in the pathogenesis of atherosclerosis. We evaluated the cytokine and chemokine production induced by CpPLD in healthy donors' monocytes and in vivo activated T cells specific for CpPLD that infiltrate atherosclerotic lesions of patients with C. pneumoniae antibodies. We also examined the helper function of CpPLD-specific T cells for monocyte matrix metalloproteinase (MMP)-9 and tissue factor (TF) production as well as the CpPLD-induced chemokine expression by human venular endothelial cells (HUVECs). We report here that CpPLD is a TLR4 agonist able to induce the expression of IL-23, IL-6, IL-1\u3b2, TGF-\u3b2, and CCL-20 in monocytes, as well as CXCL-9, CCL-20, CCL-4, CCL-2, ICAM-1, and VCAM-1 in HUVECs. Plaque-derived T cells produce IL-17 in response to CpPLD. Moreover, CpPLD-specific CD4(+) T lymphocytes display helper function for monocyte MMP-9 and TF production. CpPLD promotes Th17 cell migration through the induction of chemokine secretion and adhesion molecule expression on endothelial cells. These findings indicate that CpPLD is able to drive the expression of IL-23, IL-6, IL-1\u3b2, TGF-\u3b2, and CCL-20 by monocytes and to elicit a Th17 immune response that plays a key role in the genesis of atherosclerosis