Facial ulcers in patients with COVID-19 admitted to ICU: review of the evidence.

Objective: Many patients with COVID-19 admitted to intensive care undergo prone positioning. These patients are at risk of developing facial pressure ulcers (PUs). This study aimed to identify evidence-based recommendations to prevent or reduce their incidence.

Endothelial microparticles mediate inflammation-induced vascular calcification.

Stimulation of endothelial cells (ECs) with TNF-α causes an increase in the expression of bone morphogenetic protein-2 (BMP-2) and the production of endothelial microparticles (EMPs). BMP-2 is known to produce osteogenic differentiation of vascular smooth muscle cells (VSMCs). It was found that EMPs from TNF-α-stimulated endothelial cells (HUVECs) contained a significant amount of BMP-2 and were able to enhance VSMC osteogenesis and calcification.

Klotho Prevents NFκB Translocation and Protects Endothelial Cell From Senescence Induced by Uremia.

In patients with renal disease, uremia raises oxidative stress and senescence in endothelial cells, which can lead to endothelial dysfunction and cardiovascular disease. Klotho protein is a β-glucuronidase capable of hydrolyzing steroid β-glucuronides. This protein is recognized as an antiaging gene, that modulate both stress-induced senescence and functional response.

Magnesium inhibits Wnt/β-catenin activity and reverses the osteogenic transformation of vascular smooth muscle cells.

Magnesium reduces vascular smooth muscle cell (VSMC) calcification in vitro but the mechanism has not been revealed so far. This work used only slightly increased magnesium levels and aimed at determining: a) whether inhibition of magnesium transport into the cell influences VSMC calcification, b) whether Wnt/β-catenin signaling, a key mediator of osteogenic differentiation, is modified by magnesium and c) whether magnesium can influence already established vascular calcification. Human VSMC incubated with high phosphate (3.

Klotho modulates the stress response in human senescent endothelial cells.

Lack of Klotho expression in mice leads to premature aging and age-related diseases, including vascular diseases. The aim of this study was to determine how endothelial cell line senescence affects Klotho expression and whether intra- or extracellular Klotho has any effect on the response of senescent cells to oxidative stress. The study was performed using human endothelial cells (HUVEC); cell aging was obtained by prolongation of cell division to 42 population doublings (PD).

Localization, distribution, and function of the calcium-sensing receptor in sperm.

The intracellular movement of calcium, through calcium channels, plays a major role on sperm cell function. The calcium-sensing receptor (CaSR), a molecular mechanism by which many cells detect changes in extracellular calcium concentration, has not been described in spermatozoa. The aim of this study was to investigate the expression of the CaSR in testicular tissue and sperm cells and the functional consequences of spermatozoid CaSR activation by calcimimetics.

High-phosphate-induced calcification is related to SM22α promoter methylation in vascular smooth muscle cells.

Hyperphosphatemia is closely related to vascular calcification in patients with chronic kidney disease. Vascular smooth muscle cells (VSMCs) exposed to high phosphate concentrations in vitro undergo phenotypic transition to osteoblast-like cells. Mechanisms underlying this transdifferentiation are not clear.

Bacterial DNA prolongs the survival of inflamed mononuclear cells in haemodialysis patients.

Background: Chronic kidney disease (CKD) patients show evidence of chronic inflammation with mononuclear cell activation which is mainly caused by uraemia itself and is exacerbated by haemodialysis. Small fragments of bacterial DNA (DNAb) are ubiquitous contaminants, which are capable of passing through dialyser membranes causing the stimulation of cells of the immune system. The aim of this study was to evaluate whether DNAb contamination may have an effect on apoptosis of activated monocytes from CKD-5 patients.

Replicative senescence in patients with chronic kidney failure.

Background: Chronic activation of immunocompetent cells may lead to stress-induced premature senescence (SIPS); these senescent cells are characterized by a decrease in telomere length. The present study evaluates SIPS in circulating immunocompetent cells from predialysis patients, patients on hemodialysis, and in renal transplant patients with normal renal function.

Methods: Determination of telomere length by flow-fluorescence in situ hybridization (FISH), expression of surface molecules, and evaluation of apoptosis was performed by flow cytometry.

Antibody-mediated pure red-cell aplasia (PRCA): the Spanish experience.

Background: The incidence of antibody (Ab)-mediated pure red-cell aplasia (PRCA) in patients with chronic kidney disease (CKD) has increased between 1998 and 2002. After initially responding to treatment with recombinant human erythropoietic agents for CKD-associated anemia, patients became treatment-refractory and severely anemic. Although most PRCA cases have occurred in Europe, the varying epidemiologies among individual countries have not been well characterized.

Antibody-mediated pure red cell aplasia (PRCA): ensuring future progress by collecting data from a registry.

The recent emergence of antibody (Ab)-mediated pure red cell aplasia (PRCA) resulting from administration of certain erythropoiesis-stimulating agents (ESAs) has heightened awareness of the potential for this disorder in patients receiving ESAs for anaemia associated with chronic kidney disease (CKD). The Spanish Society of Nephrology sponsored an independent registry for analysis of patients who developed epoetin-induced, Ab-mediated PRCA in Spain. Twelve patients from 11 regional hospitals were included in the Spanish PRCA registry from November 2000 to December 2002 that met the criteria for Ab-mediated PRCA.

The influence of the progression of secondary hyperparathyroidism on the set point of the parathyroid hormone-calcium curve.

The influence of secondary hyperparathyroidism (2 HPT) on the set point of the parathyroid hormone (PTH)-Ca(2+) curve is controversial. In vitro experiments have shown an increase in the set point. However, clinical studies with hemodialysis patients have provided a variety of results (increases, decreases and no changes in the set point have been reported).

The imbalance in the ratio of Th1 and Th2 helper lymphocytes in uraemia is mediated by an increased apoptosis of Th1 subset.

Background: In uraemia there is a reduction in the total number of T lymphocytes and an imbalance in the ratio of Th1/Th2 T-helper (Th) lymphocytes. A higher rate of apoptosis in T lymphocytes has been reported in haemodialysis patients. The aims of the present study were to assess the Th1/Th2 pattern in uraemia and to evaluate whether a relative increase in Th1 apoptosis may explain the Th1/Th2 imbalance observed in uraemic patients.

Pre-emptive oral ganciclovir can reduce the risk of cytomegalovirus disease in liver transplant recipients.

A cohort of 65 liver transplant recipients was prospectively monitored with qualitative polymerase chain reaction (PCR) in plasma. The first 25 patients did not receive prophylaxis. From a consecutive group of 40 recipients, 11 high-risk patients donor CMV-seropositive/receptor CMV-seronegative (D+/R-), persistent CMV replication) received pre-emptive oral ganciclovir (1000 mg three times daily), when a marker of risk was identified, until day 90.

Cell apoptosis and hemodialysis-induced inflammation.

Hemodialysis patients exhibit a defective immune response leading to an increased susceptibility of infections and neoplasms. Far from being helpful, dialytic therapy per se also may be responsible for this acquired immunodeficiency. Dialysis membranes and bacterial products present in dialysis water may trigger and even perpetuate an abnormal mononuclear cell activation.

Role of adhesion molecules in mononuclear cell apoptosis induced by cuprophan hemodialysis membranes.

Background/aim: Hemodialysis with Cuprophan (CU) membranes induces mononuclear cell activation, leading to increased expression of adhesion molecules, formation of cell aggregates, and apoptosis. It is likely that structure(s) of the CU membrane interact with mononuclear cell surface molecules which transduce biochemical signals to the cell. Interactions between adhesion molecules and extracellular matrix have been implicated in cell activation, proliferation, and/or apoptosis.

[Prevalence of primary mutations in human immunodeficiency virus with resistance to nucleoside analogues in previously untreated patients from Andalusia. Andalusian Group for the Study of Infectious diseases (GAEI)].

Background: To analyze the frequency of HIV primary mutations to nucleosides analogues in Andalusia.

Patients And Method: Genotype study (LiPA) of mutations in codons M41L, T69D, K70R, L74V, M184V, T215Y/F and RT75G-S was performed in 106 HIV-naive patients from 12 Andalusian hospitals, with viral load over 5000 copies of RNA/ml.

Results: Reliable results were obtained in 96 patients; 11 of them (11.

Allergens induce apoptosis in lymphocytes from atopic patients.

Repeated stimulation of immune cells may induce an "activation-induced cell death" (AICD) program. Allergy is characterized by the cyclic activation of allergen-reactive immune cells. To study the effects of allergen stimulation in cell proliferation and apoptosis in atopic subjects, peripheral blood mononuclear cells (PBL) from 40 atopic patients with positive reactivity to the allergens Olea Europaea (OE) and Lollium Perenne (LP) (20 without immunotherapy and 20 with specific immunotherapy) and 10 normal subjects were cultured with the allergens OE and LP.

Human herpesvirus-6 and the course of human immunodeficiency virus infection.

The aim of this study is to investigate the relationship between human herpesvirus type 6 (HHV-6) and cytomegalovirus (CMV) infection and progression of AIDS disease. A group of 52 HIV-1-seropositive patients was examined for HHV-6 DNA expression in peripheral blood mononuclear cells and for CMV DNA in serum. We found that 21.

The CD26 antigen is coupled to protein tyrosine phosphorylation and implicated in CD16-mediated lysis in natural killer cells.

The levels of CD26 expression, their capacity to induce protein tyrosine phosphorylation and their functional implication in natural killer (NK) cytolysis have been studied. It was found that only a small fraction (12-15%) of peripheral NK cells expresses CD26 compared with the high expression (99%) found in NK clones. The protein tyrosine phosphorylation mediated by means of CD26 activation was studied in NK cells treated with the anti-CD26 MoAb 134-2C2, and two new proteins of 50 and 21 kDa appeared phosphorylated in tyrosine residues.

Selective decrease of CD26 expression in T cells from HIV-1-infected individuals.

The decrease of CD4+ cells in AIDS patients is widely documented, although the selective loss within different subsets of CD4+ cells and the mechanisms involved in this phenomenon are controversial. In the present report we have analyzed the proliferative response to Ag and mitogen of peripheral blood T lymphocytes from HIV-infected individuals, the phenotype profile of CD26+ and CD26- subset of cells and their infectivity by the HIV. The expression of CD26 Ag, either in CD4+ or CD8+ cells, was clearly diminished in all the patients tested.

CD26 induces T-cell proliferation by tyrosine protein phosphorylation.

CD26 antigen distribution among lymphoid cells and its participation in the process of lymphocyte activation and proliferation has been widely documented. However, the molecular and biochemical mechanisms coupled to the CD26 molecule are not yet known. With different monoclonal antibodies (mAb) we have detected that approximately 56% of CD4+ and 35% of CD8+ cells from peripheral blood lymphocytes express CD26 and the expression of this antigen is required for antigen- but not for mitogen-induced proliferation unless exogenous interleukin-2 (IL-2) is added to the culture.