Structural basis of eukaryotic cell targeting by type III secretion system (T3SS) effectors

Type III secretion systems (T3SS) are macromolecular complexes that translocate a wide number of effector proteins into eukaryotic host cells. Once within the cytoplasm, many T3SS effectors mimic the structure and/or function of eukaryotic proteins in order to manipulate signaling cascades, and thus play pivotal roles in colonization, invasion, survival and virulence. Structural biology techniques have played key roles in the unraveling of bacterial strategies employed for mimicry and targeting. This review provides an overall view of our current understanding of structure and function of T3SS effectors, as well as of the different classes of eukaryotic proteins that are targeted and the consequences for the infected cell.     

Epstein-Barr Virus–Related Post-Transplant Lymphoproliferative Disorders in Cystic Fibrosis Lung Transplant Recipients: A Case Series

Background

Solid organ transplantation is associated with a higher risk of Epstein-Barr virus (EBV)–related lymphoproliferative disease due to immunosuppressive regimen. Little evidence is currently available on post-transplant lymphoproliferative disorders (PTLDs) in the lung transplant (LuTx) setting, particularly in cystic fibrosis (CF) recipients.

Effect of silica coating and laser treatment on the flexural strength,surface characteristics,and bond strength of a dental zirconia

This study investigated the effect of irradiation with an erbium‐doped yttrium aluminium garnet (Er:YAG) laser and coating with silica on the surface characteristics, bond strength, and flexural strength of dental zirconia. Three hundred and forty‐three standard zirconia specimens were created, and 49 were assigned to each of seven surface treatment groups: (i) no treatment; Er:YAG laser (80 mJ/2 Hz) with pulse widths of 50 μs (ii), 100 μs (iii), 300 μs (iv), or 600 μs (v); or tribochemical silica coating at the partially sintered stage (vi) or after sintering was complete (vii). All specimens were sintered after the surface treatments, except for the group in which specimens were sintered before treatment. The study outcomes were roughness, surface loss, microshear bond strength (μSBS), and biaxial flexural strength (BFS). Mean roughness and surface loss values were significantly higher in specimens from irradiated groups than in those from silica‐coated groups. Regarding μSBS, after aging, specimens from all experimental groups presented very low and similar μSBS values, irrespective of the surface treatment. Silica coating after sintering yielded the highest BFS (1149.5 ± 167.6 MPa), while coating partially sintered specimens with silica resulted a BFS (826.9 ± 60.9 MPa) similar to that of the untreated control group (794.9 ± 101.7 MPa). Laser treatments, irrespective of pulse width used, significantly decreased the BFS. In the group treated with laser at 300 μs pulse width, specimens exhibited the lowest BFS value (514.1 ± 71.5 MPa). Adhesion to zirconia was not stable after aging, regardless of the surface treatment implemented.     

A foetal tile from an archaeological site: anthropological investigation of human remains recovered in a medieval cemetery in Northern Italy

Background: The recovery of foetal remains is very sporadic in archaeology, especially due the scarce degree of bone mineralisation. This paper presents the singular archaeological discovery of a foetal tile preserving the bone remains, object of our anthropological examination.

Materials and methods: The foetal tile was discovered during an archaeological excavation in a medieval site (Northern Italy). The tile was analysed by CT scan and later, human remains were anthropologically examined.

Results: The archaeological investigation revealed a special ritual destined to foetuses while forensic anthropological analysis allowed estimating the gestational age near to 21–24?weeks.     

Primary cardiac T-cell lymphoma

Primary cardiac lymphoma (PCL), defined as a lymphoma clinically mimicking cardiac disease, with the bulk of the tumor located intrapericardially, is extremely rare in immunocompetent patients. Clinical manifestations vary depending on sites of involvement in the heart and include chest pain, arrhythmias, pericardial effusion, and heart failure. Diagnosis is often difficult and may require invasive procedures; in some cases, diagnosis is not made until autopsy. Histologically, nearly all cases of PCL reported thus far have been of B-cell origin. In this report, we describe a case of PCL of T-cell origin in an adult immunocompetent patient, the second reported in the literature to the best of our knowledge, and provide a brief overview of the features of previously published PCL cases.     

Adenosine affects expression of membrane molecules,cytokine and chemokine release,and the T-cell stimulatory capacity of human dendritic cells

Dendritic cells (DCs) express functional purinergic type 1 receptors, but the effects of adenosine in these antigen-presenting cells have been only marginally investigated. Here, we further characterized the biologic activity of adenosine in immature DCs (iDCs) and lipopolysaccharide (LPS)-matured DCs (mDCs). Chronic stimulation with adenosine enhanced the macropinocytotic activity and the membrane expression of CD80, CD86, major histocompatibility complex (MHC) class I, and HLA-DR molecules on iDCs. Adenosine also increased LPS-induced CD54, CD80, MHC class I, and HLA-DR molecule expression in mDCs. In addition, adenosine dose-dependently inhibited tumor necrosis factor alpha and interleukin-12 (IL-12) release, whereas it enhanced the secretion of IL-10 from mDCs. The use of selective receptor agonists revealed that the modulation of the cytokine and cell-surface marker profile was due to activation of A(2) adenosine receptor. Functionally, adenosine reduced the allostimulatory capacity of iDCs, but not of mDCs. More important, DCs matured in the presence of adenosine had a reduced capacity to induce T helper 1 (Th1) polarization of naive CD4(+) T lymphocytes. Finally, adenosine augmented the release of the chemokine CCL17 and inhibited CXCL10 production by mDCs. In aggregate, the results provide initial evidence that adenosine diminishes the capacity of DCs to initiate and amplify Th1 immune responses.