＜Editors' Choice＞ Mesenchymal stem/stromal cells generated from induced pluripotent stem cells are highly resistant to senescence.

The use of mesenchymal stem/stromal cells (MSCs) has attracted attention in the field of regenerative medicine based on their anti-inflammatory and tissue repair-promoting effects. Bone marrow is widely used as a source of MSCs; however, the performance of bone marrow (BM)-MSCs deteriorates as the cells age along with cell passaging. Recently, it has been reported that MSCs can be generated from induced pluripotent stem cells (iPSCs), which is expected to represent a new source of MSCs. However, few studies have investigated aging in iPSC-derived MSCs (iMSCs) and their functions. In this study, we investigated whether iMSCs overcome cellular senescence compared to that in BM-MSCs. Cellular senescence was quantitatively evaluated by staining iMSCs and BM-MSCs with fluorescein di-ß-D-galactopyranoside (FDG) and following flow cytometer analysis. The hepatocyte growth factor (HGF) concentration in the culture supernatant was also measured as a factor in the therapeutic efficacy of nephritis. The iMSCs did not reach their proliferation limit and their morphology did not change even after 10 passages. The FDG positivity of BM-MSCs increased with passaging, whereas that in iMSCs did not increase. The HGF concentration increased with passaging in iMSCs. In conclusion, our results suggest that iMSCs may be less susceptible to senescence than BM-MSCs and may be used in clinical applications.

The Impact of Liver Chemistries on Respiratory Failure among Hemodialysis Patients with COVID-19 during the Omicron Wave.

Objective Although the coronavirus disease 2019 (COVID-19) Omicron variant causes less severe symptoms than previous variants, early indicators for respiratory failure are needed in hemodialysis patients, who have a higher mortality rate than the general population. Liver chemistries are known to reflect the severity of COVID-19 in the general population. This study explored the early indicators for worsened respiratory failure based on patient characteristics, including liver chemistries. Methods This retrospective study included 117 patients admitted for COVID-19 during the Omicron wave. Respiratory failure was defined as oxygen requirement during treatment. Information on the symptoms and clinical characteristics, including liver chemistries [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)], at admission was collected. Results Thirty-five patients (29.9%) required oxygen supply during treatment. In the multivariate logistic regression analyses, AST [odds ratio (OR) 1.06, 95% confidence interval (CI) 1.00-1.13, p=0.029], ALT (OR 1.09, 95% CI 1.02-1.18, p=0.009), and moderate COVID-19 illness (Model including AST, OR 6.95, 95% CI 2.23-23.17, p<0.001; Model including ALT, OR 7.19, 95% CI 2.21-25.22, p=0.001) were independent predictors for respiratory failure. Based on the cutoff values determined by the receiver operating characteristic curve, higher AST (≥23 IU/L) and ALT levels (≥14 IU/L) were also independently associated with respiratory failure (higher AST: 64.3% vs. 18.8%, OR 3.44, 95% CI 1.08-11.10, p=0.035; higher ALT: 48.8% vs. 19.7%, OR 4.23, 95% CI 1.34-14.52, p=0.013, respectively). Conclusion The measurement of AST and ALT levels at baseline may help predict oxygen requirement in hemodialysis patients with COVID-19.

Non-A Blood Type Is a Risk Factor for Poor Cardio-Cerebrovascular Outcomes in Patients Undergoing Dialysis.

The clinical impact of ABO blood type on cardio-cerebrovascular outcomes in patients undergoing dialysis has not been clarified. A total of 365 hemodialysis patients participated in the current study. The primary endpoint was defined as a composite including cardio-cerebrovascular events and cardio-cerebrovascular death. The primary endpoint was observed in 73 patients during a median follow-up period of 1182 days, including 16/149 (11%) with blood type A, 22/81 (27%) with blood type B, 26/99 (26%) with blood type O, and 9/36 (25%) with blood type AB. At baseline, no difference was found in the echocardiographic parameters. Multivariable Cox regression analyses revealed that blood type (type A vs. non-A type; hazard ratio (HR): 0.46, 95% confidence interval (95% CI): 0.26-0.81, p = 0.007), age (per 10-year increase; HR: 1.47, 95% CI: 1.18-1.84), antiplatelet or anticoagulation therapy (HR: 1.91, 95% CI: 1.07-3.41), LVEF (per 10% increase; HR: 0.78, 95% CI: 0.63-0.96), and LV mass index (per 10 g/m2 increase; HR: 1.07, 95% CI: 1.01-1.13) were the independent determinants of the primary endpoint. Kaplan-Meier curves also showed a higher incidence of the primary endpoint in the non-A type than type A (Log-rank p = 0.001). Dialysis patients with blood type A developed cardio-cerebrovascular events more frequently than non-A type patients.

A rare case of myocardial calcification secondary to acute myocarditis due to an Escherichia coli infection.

Myocardial calcification secondary to acute myocarditis is a rare but possibly life-threatening complication. We report a 43-year-old woman with minimal change nephrotic syndrome who developed sepsis caused by Escherichia coli. We simultaneously detected the complication of acute myocarditis in the patient. Although echocardiography showed hypokinesis of the apical segment when acute myocarditis was diagnosed, no sign of myocardial calcification was observed. After two weeks, a CT showed myocardial calcification in the same area. Although myocardial calcification was still observed 12 months later, the patient's cardiac function had improved.

A case of perirenal extramedullary hematopoiesis in a patient with primary myelofibrosis.

Extramedullary hematopoiesis (EMH) is hematopoiesis in organs outside the bone marrow and most frequently occurs in the liver, spleen, and lymph nodes. We report a case of perirenal EMH revealed by kidney biopsy in a patient with primary myelofibrosis. We observed only bilateral kidney enlargement with plain computed tomography (CT) and ultrasonography before obtaining a renal biopsy. We obtained a percutaneous biopsy from the lower pole of the left kidney using ultrasonographic guidance. Ultrasonography just after the renal biopsy revealed no bleeding around the kidney. However, early the next morning, the patient developed severe hemorrhagic shock. Contrast-enhanced CT at that time revealed a massive hematoma in the left posterior perirenal space and bilateral abnormalities of the perirenal soft tissues. In patients with primary myelofibrosis, if plain CT shows an abnormal renal enlargement, EMH should be considered. In addition, a contrast-enhanced CT should be obtained before performing a percutaneous renal biopsy to assess for the possibility of perirenal EMH in these patients.