Single-step batch fabrication of microfluidic paper-based analytical devices with a 3D printer and their applications in nanoenzyme-enhanced visual detection of dopamine.

Wax printing is the most widely used method for fabricating microfluidic paper-based analytical devices (µPADs), but it still suffers from disadvantages like discontinuation of wax printers and need for additional equipment for heating treatment. To address these issues, this work initially describes a new class of wax printing approach for high-precision, batch fabrication of µPADs using a household 3D printer. It only involves a one patterning step of printing polyethylene wax into rice paper body. Under optimized parameters, a fabrication resolution, namely the minimum hydrophilic channel width, down to ~189 ± 30 µm could be achieved. In addition, the analytical applicability of such polyethylene wax-patterned µPADs was demonstrated well with enhanced colorimetric detection of dopamine as a model analyte by combining metal-organic framework (MOF) based nanoenzymes (ZIF-67) with a smartphone (for portable quantitative readout). The developed nanosensor could linearly detect dopamine over a concentration range from 10 to 1000 µM, with a detection limit of ca. 2.75 µM (3σ). The recovery results for analyzing several real samples (i.e., pig feed, chicken feed, pork and human serum) were between 91.82 and 102.79%, further validating its good detection accuracy for potential practical applications in food safety and medical diagnosis.

Neurological manifestations and risk factors associated with poor prognosis in hospitalized children with Omicron variant infection.

There are increasing reports of neurological manifestation in children with coronavirus disease 2019 (COVID-19). However, the frequency and clinical outcomes of in hospitalized children infected with the Omicron variant are unknown. The aim of this study was to describe the clinical characteristics, neurological manifestations, and risk factor associated with poor prognosis of hospitalized children suffering from COVID-19 due to the Omicron variant. Participants included children older than 28 days and younger than 18 years. Patients were recruited from December 10, 2022 through January 5, 2023. They were followed up for 30 days. A total of 509 pediatric patients hospitalized with the Omicron variant infection were recruited into the study. Among them, 167 (32.81%) patients had neurological manifestations. The most common manifestations were febrile convulsions (n = 90, 53.89%), viral encephalitis (n = 34, 20.36%), epilepsy (n = 23, 13.77%), hypoxic-ischemic encephalopathy (n = 9, 5.39%), and acute necrotizing encephalopathy (n = 6, 3.59%). At discharge, 92.81% of patients had a good prognosis according to the Glasgow Outcome Scale (scores ≥ 4). However, 7.19% had a poor prognosis. Eight patients died during the follow-up period with a cumulative 30-day mortality rate of 4.8% (95% confidence interval (CI) 1.5-8.1). Multivariate analysis revealed that albumin (odds ratio 0.711, 95% CI 0.556-0.910) and creatine kinase MB (CK-MB) levels (odds ratio 1.033, 95% CI 1.004-1.063) were independent risk factors of poor prognosis due to neurological manifestations. The area under the curve for the prediction of poor prognosis with albumin and CK-MB was 0.915 (95%CI 0.799-1.000), indicating that these factors can accurately predict a poor prognosis.          Conclusion: In this study, 32.8% of hospitalized children suffering from COVID-19 due to the Omicron variant infection experienced neurological manifestations. Baseline albumin and CK-MB levels could accurately predict poor prognosis in this patient population. What is Known: • Neurological injury has been reported in SARS-CoV-2 infection; compared with other strains, the Omicron strain is more likely to cause neurological manifestations in adults. • Neurologic injury in adults such as cerebral hemorrhage and epilepsy has been reported in patients with Omicron variant infection. What is New: • One-third hospitalized children with Omicron infection experience neurological manifestations, including central nervous system manifestations and peripheral nervous system manifestations. • Albumin and CK-MB combined can accurately predict poor prognosis (AUC 0.915), and the 30-day mortality rate of children with Omicron variant infection and neurological manifestations was 4.8%.

Targeting SMYD2 promotes ferroptosis and impacts the progression of pancreatic cancer through the c-Myc/NCOA4 axis-mediated ferritinophagy.

BACKGROUND: Pancreatic cancer (PC) is characterized by a poor prognosis and limited treatment options. Ferroptosis plays an important role in cancer, SET and MYND domain-containing protein 2 (SMYD2) is widely expressed in various cancers. However, the role of SMYD2 in regulating ferroptosis in PC remains unexplored. This study aimed to investigate the role of SMYD2 in mediating ferroptosis and its mechanistic implications in PC progression. METHODS: The levels of SMYD2, c-Myc, and NCOA4 were assessed in PC tissues, and peritumoral tissues. SMYD2 expression was further analyzed in human PC cell lines. In BxPC3 cells, the expression of c-Myc, NCOA4, autophagy-related proteins, and mitochondrial morphology, was evaluated following transfection with si-SMYD2 and treatment with autophagy inhibitors and ferroptosis inhibitors. Ferroptosis levels were quantified using flow cytometry and ELISA assays. RNA immunoprecipitation was conducted to elucidate the interaction between c-Myc and NCOA4 mRNA. A xenograft mouse model was constructed to validate the impact of SMYD2 knockdown on PC growth. RESULTS: SMYD2 and c-Myc were found to be highly expressed in PC tissues, while NCOA4 showed reduced expression. Among the PC cell lines studied, BxPC3 cells exhibited the highest SMYD2 expression. SMYD2 knockdown led to decreased c-Myc levels, increased NCOA4 expression, reduced autophagy-related protein expression, mitochondrial shrinkage, and heightened ferroptosis levels. Additionally, an interaction between c-Myc and NCOA4 was identified. In vivo, SMYD2 knockdown inhibited tumor growth. CONCLUSIONS: Targeting SMYD2 inhibits PC progression by promoting ferritinophagy-dependent ferroptosis through the c-Myc/NCOA4 axis. These findings provide insights into potential diagnostic and therapeutic strategies for PC.