, an outbreak of coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began in China and spread rapidly worldwide. It is unknown whether hemodialysis patients represent a distinct group of patients with certain characteristics that may make them susceptible to infection or severe disease. In this case report, we describe the clinical and epidemiologic features of COVID-19 infection in 201 maintenance hemodialysis patients in Zhongnan Hospital of Wuhan University, including 5 maintenance hemodialysis patients who contracted COVID-19 infection. Of the 5 patients with COVID-19 infection, one had a definite history of contact with an infected person. The age range of the patients was 47 to 67 years. Diarrhea (80%), fever (60%), and fatigue (60%) were the most common symptoms. Lymphopenia occurred in all patients. Computed tomography of the chest showed ground glass opacity in the lungs of all patients. Up to February 13, 2020, none of the patients had developed severe complications (acute respiratory distress syndrome, shock, or multiple organ dysfunction) or died. Complete author and article information provided before references.

Diabetic nephropathy (DN) is a kind of diabetic complication with capillary damage, and its pathogenesis remains obscure. Recently, microRNAs have been identified as diagnostic biomarkers in various diseases including DN. Toll-like receptor 4 (TLR4) contributes to inflammation, and it has been implicated in diabetes pathophysiology. This study was designed to investigate the role of miR-874 and TLR4 in a streptozotocin (STZ)-induced DN rat model and glucose-induced mouse podocyte model. In the current study, we reported that miR-874 was markedly downregulated in DN rats and glucose-induced mouse podocytes compared with the corresponding control groups with the activation of TLR4. In addition, we observed that overexpression of miR-874 was able to alleviate renal injury in DN rats. The cell counting kit (CCK-8) assay and 5-Ethynyl-2'-deoxyuridine (EdU) assay demonstrated that glucose simulation significantly inhibited podocyte proliferation and induced cell apoptosis, which can be reversed by miR-874 mimics significantly. Notably, miR-874 overexpression dramatically attenuated the inflammatory response, indicated by the decreased levels of interleukin-6, L-1β, and tumor necrosis factor α (TNF-α). Finally, the binding correlation between miR-874 and TLR4 was confirmed by carrying out dual-luciferase reporter assay in our study. It was found that overexpression of miR-874 depressed TLR4 levels in podocytes. These findings implied for the first time that the overexpression of miR-874 repressed glucose-triggered podocyte injury through targeting TLR4 and suggested that miR-874/TLR4 axis might represent a pathological mechanism of DN.

To investigate the effects of calcitriol on angiotensin-converting enzyme (ACE) and ACE2 in diabetic nephropathy. Streptozotocin (STZ) induced diabetic rats were treated with calcitriol for 16 weeks. ACE/ACE2 and mitogen activated protein kinase (MAPK) enzymes were measured in the kidneys of diabetic rats and rat renal tubular epithelial cells exposed to high glucose. Calcitriol reduced proteinuria in diabetic rats without affecting calcium-phosphorus metabolism. ACE and ACE2 levels were significantly elevated in diabetic rats compared to those in control rats. The increase in ACE levels was greater than that of ACE2, leading to an elevated ACE/ACE2 ratio. Calcitriol reduced ACE levels and ACE/ACE2 ratio and increased ACE2 levels in diabetic rats. Similarly, high glucose up-regulated ACE expression in NRK-52E cells, which was blocked by the p38 MAPK inhibitor SB203580, but not the extracellular signal-regulated kinase (ERK) inhibitor FR180204 or the c-Jun N-terminal kinase (JNK) inhibitor SP600125. High glucose down-regulated ACE2 expression, which was blocked by FR180204, but not SB203580 or SP600125. Incubation of cells with calcitriol significantly inhibited p38 MAPK and ERK phosphorylation, but not JNK phosphorylation, and effectively attenuated ACE up-regulation and ACE2 down-regulation in high glucose conditions. The renoprotective effects of calcitriol in diabetic nephropathy were related to the regulation of tubular levels of ACE and ACE2, possibly by p38 MAPK or ERK, but not JNK pathways.

Renal interstitial fibrosis is a necessary step in the progression of chronic kidney to end stage renal disease. MicroRNA-29 (miR-29) has been shown to play essential roles in epithelial-mesenchymal transition (EMT), and thus may contribute to the regulation of renal interstitial fibrosis. However, the role of miR-29 in the regulation of EMT during chronic kidney disease and renal transplantation has been a source of intense debate, and the mechanisms underlying this process are incompletely understood. In this study, we investigated the function of miR-29b in the regulation of EMT and to gain a better understanding of the mechanism by which miR-29b modulates EMT by targeting the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway during the process of renal interstitial fibrosis. The rat proximal tubular epithelial cell line NRK-52E was cultured in DMEM and treated with angiotensin II (Ang II) at various concentrations. RT-PCR was performed to investigate changes in the levels of expression of miR-29b in NRK-52E cells and western blotting was used to analyze the expression of PI3K, p-AKT, vimentin and keratin 18. The result of the study show that treatment of NRK-52E cells with Ang II induced the transition of the cellular phenotype from epithelial to mesenchymal and upregulated the PI3K/AKT signaling pathway; this was also found following treatment with a phosphatase and tensin homolog on chromosome 10 (PTEN)-specific inhibitor. Increased expression of miR-29b was able to reverse the phenotype induced by Ang II in NRK-52E cells and blocking miR-29b activity with an miR-29b inhibitor resulted in enhanced EMT. Additionally, the PI3K/AKT signaling pathway was found to be suppressed in the presence of enhanced expression of miR-29b by direct binding to 3'-untranslated region (3'-UTR) of PIK3R2. We concluded that miR-29b plays an important role in the negative regulation of Ang II-induced EMT via PI3K/AKT signaling pathway and propose that enhancing miR-29b level or blocking PI3K/AKT signaling pathway may be a novel therapeutic target in renal interstitial fibrosis.

Background Coronavirus disease 2019 (COVID-19) is an emerging infectious disease that first manifested in humans in Wuhan, Hubei Province, China, in December 2019, and has subsequently spread worldwide. Methods We conducted a retrospective, single-center case series of the seven maintenance hemodialysis (HD) patients infected with COVID-19 at Zhongnan Hospital of Wuhan University from 13 January to 7 April 2020 and a proactive search of potential cases by chest computed tomography (CT) scans. Results Of 202 HD patients, 7 (3.5%) were diagnosed with COVID-19. Five were diagnosed by reverse transcription polymerase chain reaction (RT-PCR) because of compatible symptoms, while two were diagnosed by RT-PCR as a result of screening 197 HD patients without respiratory symptoms by chest CT. Thirteen of 197 patients had positive chest CT features and, of these, 2 (15%) were confirmed to have COVID-19. In COVID-19 patients, the most common features at admission were fatigue, fever and diarrhea [5/7 (71%) had all these]. Common laboratory features included lymphocytopenia [6/7 (86%)], elevated lactate dehydrogenase [3/4 (75%)], D-dimer [5/6 (83%)], high-sensitivity C-reactive protein [4/4 (100%)] and procalcitonin [5/5 (100%)]. Chest CT showed bilateral patchy shadows or ground-glass opacity in the lungs of all patients. Four of seven (57%) received oxygen therapy, one (14%) received noninvasive and invasive mechanical ventilation, five (71%) received antiviral and antibacterial drugs, three (43%) recieved glucocorticoid therapy and one (14%) received continuous renal replacement therapy. As the last follow-up, four of the seven patients (57%) had been discharged and three patients were dead. Conclusions Chest CT may identify COVID-19 patients without clear symptoms, but the specificity is low. The mortality of COVID-19 patients on HD was high.