Clinical presentation and outcomes of chronic dialysis patients with COVID-19: A single center experience from Greece.

Background: Coronavirus disease 2019 (COVID-19) is still a menacing pandemic, especially in vulnerable patients. Morbidity and mortality from COVID-19 in maintenance hemodialysis (MHD) patients are considered worse than those in the general population, but vary across continents and countries in Europe.

Aim: To describe the clinical course and outcomes of hospitalized MHD patients with COVID-19 in a retrospective observational single center study in Greece.

The paradigm shift from polycythemia to anemia in COPD: the critical role of the renin-angiotensin system inhibitors.

Introduction: Although polycythemia has been considered a common adverse event in COPD, anemia is reported more often and has gained more importance than polycythemia over the last thirty years.

Areas Covered: Factors considered to be associated with the development of anemia in COPD have included: Aging and kidney dysfunction with erythropoietin deficiency and bone marrow suppression due to uremic toxins; heart failure (HF), often encountered in COPD and accompanied by anemia in one-third of the cases; Low-grade chronic inflammation, directly suppressing bone marrow and diminishing iron absorption and utilization via increased hepcidin levels; long-term oxygen therapy (LTOT), ameliorating chronic hypoxia, and most important, RAS inhibitors, which are widely used for the comorbidities associated with COPD (hypertension, HF, CKD, diabetes) and have previously been shown to lower hematocrit values or cause anemia in various clinical conditions.

Expert Opinion: Introduction of LTOT in COPD and especially the established use of RAS inhibitors form the basis for the shift from polycythemia to anemia in COPD.

Case Report of Cardiorenal Syndrome with Ascites and Listeria monocytogenes Peritonitis: The Role of Large-Volume Paracentesis and Albumin Replacement.

BACKGROUND Spontaneous bacterial peritonitis is a common infection in hospitalized patients with ascites, particularly in patients with cirrhosis. Spontaneous bacterial peritonitis is often associated with acute kidney injury. The causative agents of spontaneous bacterial peritonitis are usually gram-negative bacteria, but lately, the prevalence of spontaneous bacterial peritonitis caused by gram-positive bacteria is rising.

Targeted proteomic analysis dataset of archival core human kidney biopsies to investigate the biology of hypertensive nephropathy.

Hypertensive nephropathy is the second most frequent cause of end-stage renal disease in western societies. In previous experiments in our laboratory with proteomic analysis of renal parenchyma of SHR hypertensive animals, we identified two molecules, namely SGLT2 and CLIC4, associated with the development of hypertension. Here, we apply the methodology of targeted proteomic analysis in kidney biopsies from patients with hypertensive nephropathy to study the role of SGLT2 and CLIC4 in the pathogenesis of the disease.

Siblings with coronavirus disease 2019 infection and opposite outcome-the hemodialysis's better outcome paradox: Two case reports.

Background: Coronavirus disease 2019 (COVID-19) is a highly contagious infection caused by the severe acute respiratory syndrome coronavirus 2 virus and has a unique underlying pathogenesis. Hemodialysis (HD) patients experience high risk of contamination with COVID-19 and are considered to have higher mortality rates than the general population by most but not all clinical series. We aim to highlight the peculiarities in the immune state of HD patients, who seem to have both immune-activation and immune-depression affecting their outcome in COVID-19 infection.

Impact of Angiotensin-Converting Enzyme Inhibitors or Angiotensin Receptor Blockers on Acute Kidney Injury in Emergency Medical Admissions.

Background: Acute kidney injury (AKI) has been observed in up to 20% of adult hospital admissions. Sepsis, diarrhea and heart failure, all causing reduced effective volume, are considered risk factors for AKI, especially among patients treated with medications that block the Renin-Angiotensin System (RAS), such as angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB). We aimed to determine the incidence of acute kidney injury (AKI) in emergency medical admissions in relation to the use and dosage of ACEi/ARB.

Discontinuation of the renin-angiotensin system inhibitors improves erythropoiesis in patients with lower-risk myelodysplastic syndromes.

Renin-angiotensin system (RAS) blockade by angiotensin-converting enzyme inhibitors (ACEis) or angiotensin-receptor blockers (ARBs) has been related to anemia in various situations. We aimed to investigate whether discontinuation of RAS inhibitors improves erythropoiesis in patients with lower-risk myelodysplastic syndromes (LR-MDSs). Seventy-four patients with LR-MDS were divided into three groups matched for gender and age.

Hyperferritinemia in patients with COVID-19: An opportunity for iron chelation?

Studies from China on COVID-19 revealed that nonsurvivors had cytokine storm with high IL-6 and hyperferritinemia. Iron liberated from necrotic cells may catalyze free radical production and amplify lipid peroxidation causing membrane dysfunction and multiorgan failure. Consequently, iron chelators have been successfully utilized in various experimental and clinical models of cytokine storm and multiorgan damage, such as in ischemia-reperfusion injury, sepsis, and infections.

Competing Effects of Renin Angiotensin System Blockade and Sodium-Glucose Cotransporter-2 Inhibitors on Erythropoietin Secretion in Diabetes.

Background: Anaemia is a common finding in diabetes, particularly in those patients with albuminuria or renal dysfunction and is associated with impaired erythropoietin (EPO) secretion. This review focuses on mechanisms involved in the regulation of erythropoiesis in diabetic patients in an effort to elucidate the competing effects of the renin angiotensin system (RAS) blockade and sodium-glucose cotransporter-2 (SGLT2) inhibitors on haemoglobin concentration and hematocrit values.

Summary: The RAS shows significant activation in diabetic subjects.

Inhibition of the renin-angiotensin system in the cardiorenal syndrome with anaemia: a double-edged sword.

: The term 'cardiorenal syndrome' (CRS) was introduced to describe problems related to the simultaneous existence of heart and renal insufficiency. The prevalence of anaemia in CRS is high and increases the risk of hospitalizations and death. Renin-angiotensin system (RAS) inhibition is the cornerstone therapy in cardiovascular and renal medicine.

The family of 14-3-3 proteins and specifically 14-3-3σ are up-regulated during the development of renal pathologies.

Chronic kidney disease, the end result of most renal and some systemic diseases, is a common condition where renal function is compromised due to fibrosis. During renal fibrosis, calreticulin, a multifunctional chaperone of the endoplasmic reticulum (ER) is up-regulated in tubular epithelial cells (TECs) both in vitro and in vivo. Proteomic analysis of cultured TECs overexpressing calreticulin led to the identification of the family of 14-3-3 proteins as key proteins overexpressed as well.

Transdermal Delivery of AT1 Receptor Antagonists Reduce Blood Pressure and Reveal a Vasodilatory Effect on Kidney Blood Vessels.

Background: The Renin Angiotensin System (RAS) is pharmacologically targeted to reduce blood pressure, and patient compliance to oral medications is a clinical issue. The mechanisms of action of angiotensin receptor blockers (ARBs) in reducing blood pressure are not well understood and are purported to be via a reduction of angiotensin II signaling.

Objective: We aimed to develop a transdermal delivery method for ARBs (losartan potassium and valsartan) and to determine if ARBs reveal a vasodilatory effect of the novel RAS peptide, alamandine.

IgA nephropathy in Greece: data from the registry of the Hellenic Society of Nephrology.

Background: Natural history, predisposing factors to an unfavourable outcome and the effect of various therapeutic regimens were evaluated in a cohort of 457 patients with immunoglobulin A nephropathy (IgAN) and follow-up of at least 12 months.

Methods: Patients with normal renal function and proteinuria <1 g/24 h as well as those with serum creatinine (SCr) >2.5 mg/dL and/or severe glomerulosclerosis received no treatment.

Chloride Intracellular Channel 4 Overexpression in the Proximal Tubules of Kidneys from the Spontaneously Hypertensive Rat: Insight from Proteomic Analysis.

Background: Hypertensive nephropathy, a leading cause of declining kidney function, is a multifactorial process not well understood. In order to elucidate biological processes and identify novel macromolecular components crucially involved in the process of kidney damage, the application of system biology approaches, like proteomics, is required.

Methods: Proteomic studies were performed using the renal parenchyma of spontaneously hypertensive rats (SHR) and their normotensive Wistar Kyoto controls.

Noninvasive assessment of haemodynamics in resistant hypertension: the role of the renal resistive index.

Objective: The association of resistant hypertension (RHTN) with renal haemodynamics is unclear. Our aim was to evaluate differences in haemodynamic characteristics of patients with RHTN compared with patients with controlled hypertension (HTN) at the level of the heart, kidney and aorta.

Methods: We studied 50 patients with RHTN confirmed by ambulatory blood pressure monitoring and 50 controlled hypertensive patients matched for age and sex.

Hematologic and renal improvement of monoclonal immunoglobulin deposition disease after treatment with bortezomib-based regimens.

Monoclonal immunoglobulin deposition disease (MIDD) is characterized by non-organized immunoglobulin-fragments along renal basement membranes with subsequent organ deterioration. Treatment is directed against the immunoglobulin-producing clone. We treated 18 MIDD patients with bortezomib-based regimens (12 received bortezomib-dexamethasone, 6 bortezomib-dexamethasone with cyclophosphamide).

Assessment of serum bioactive hepcidin-25, soluble transferrin receptor and their ratio in predialysis patients: Correlation with the response to intravenous ferric carboxymaltose.

Background: No reliable biomarker exists to predict responsiveness to intravenous (IV) iron (Fe) in iron deficient patients with CKD. We aimed to investigate the clinical value of bioactive Hepcidin-25 and soluble Transferrin Receptor (sTfR) levels in predialysis patients.

Patients And Methods: In this prospective study 78 stable stage III-IV CKD predialysis patients with (responders) (40 patients) and without (non-responders) (38 patients) adequate erythropoiesis after IV administration of ferric-carboxymaltose (FCM).

Circulating resistin is a significant predictor of mortality independently from cardiovascular comorbidities in elderly, non-diabetic subjects with chronic kidney disease.

Context: Resistin is associated with inflammation, atherosclerosis and cardiovascular (CV) disease.

Objective: To associate circulating resistin with all-cause and CV mortality in chronic kidney disease (CKD) patients.

Methods: Serum resistin was determined in a cohort of 80 elderly, non-diabetic patients with stable CKD at different stages in a follow-up period of 5 years.

Multicenter epidemiological study to assess the population of CKD patients in Greece: results from the PRESTAR study.

Background: Chronic Kidney Disease (CKD) is a relatively common condition not only associated with increased morbidity and mortality but also fuelling End Stage Renal Disease (ESRD). Among developed nations, Greece has one of the highest ESRD incidence rates, yet there is limited understanding of the epidemiology of earlier stages of CKD.

Methods: Cross-sectional survey of pre-dialysis CKD outpatients in nephrology clinics in the National Health Care system between October 2009 and October 2010.

Impact of hemodialysis on dyspnea and lung function in end stage kidney disease patients.

Background: Respiratory symptoms are usually underestimated in patients with chronic kidney disease undergoing maintenance hemodialysis. Therefore, we set out to investigate the prevalence of patients chronic dyspnea and the relationship of the symptom to lung function indices.

Methods: Twenty-five clinically stable hemodialysis patients were included.

Correlates of serum resistin in elderly, non-diabetic patients with chronic kidney disease.

Background: Renal function may be a major determinant of resistin levels, since most studies revealed association between elevated resistin levels and decreased glomerular filtration rate (GFR) in patients with chronic kidney disease (CKD). The aim of the present study was to test the hypothesis whether serum resistin is associated with markers of malnutrition and inflammation in elderly non-diabetic adults in different stages of CKD including hemodialysis.

Methods: This was a cross-sectional study of 80 elderly patients divided in four groups of 20 patients each according to eGFR and matched for age (+/- 5 years) and gender.

Facile and efficient syntheses of a series of N-benzyl and N-biphenylmethyl substituted imidazole derivatives based on (E)-urocanic acid, as angiotensin II AT1 receptor blockers.

In the present work, a facile and efficient route for the synthesis of a series of N-substituted imidazole derivatives is described. Docking studies have revealed that N-substituted imidazole derivatives based on (E)-urocanic acid may be potential antihypertensive leads. Therefore, new AT1 receptor blockers bearing either the benzyl or the biphenylmethyl moiety at the N-1 or N-3 position, either the (E)-acrylate or the propanoate fragment and their related acids at the C-4 position as well as a halogen atom at the C-5 position of the imidazole ring, were synthesized.