Progress in the study of circulating, cell-free nuclear DNA (ccf-nDNA) in cancer detection has led to the development of non-invasive clinical diagnostic tests and has accelerated the evaluation of ccf-nDNA abundance as a disease biomarker. Likewise, circulating, cell-free mitochondrial DNA (ccf-mtDNA) is under similar investigation. However, optimal ccf-mtDNA isolation parameters have not been established, and inconsistent protocols for ccf-nDNA collection, storage, and analysis have hindered its clinical utility. Until now, no studies have established a method for high throughput isolation that considers both ccf-nDNA and ccf-mtDNA. We initially optimized human plasma digestion and extraction conditions for maximal recovery of these DNAs using a magnetic bead-based isolation method. However, when we incorporated this method onto a high throughput platform, initial experiments found that DNA isolated from identical human plasma samples displayed plate edge effects resulting in low ccf-mtDNA reproducibility, while ccf-nDNA was less affected. Therefore, we developed a detailed protocol optimized for both ccf-mtDNA and ccf-nDNA recovery that uses a magnetic bead-based isolation process on an automated 96-well platform. Overall, we calculate an improved efficiency of recovery of ~95-fold for ccf-mtDNA and 20-fold for ccf-nDNA when compared to the initial procedure. Digestion conditions, liquid handling characteristics, and magnetic particle processor programming all contributed to increased recovery and without detectable positional effects. To our knowledge, this is the first high throughput approach optimized for ccf-mtDNA and ccf-nDNA recovery and serves as an important starting point for clinical studies.

Circulating, cell-free mitochondrial DNA (ccf-mtDNA) and nuclear DNA (ccf-nDNA) are under investigation as biomarkers for various diseases. Optimal ccf-mtDNA isolation parameters, like those outlined for ccf-nDNA, have not been established. Here, we optimized a protocol for both ccf-mtDNA and ccf-nDNA recovery using a magnetic bead-based isolation process on an automated 96-well platform. Using the optimized protocol, our data show 6-fold improved yields of ccf-mtDNA when compared to the starting protocol. Digestion conditions, liquid handling characteristics, and magnetic particle processor programming all contributed to increased recovery and improved reproducibility. To our knowledge, this is the first high-throughput approach optimized for mtDNA and nDNA recovery and serves as an important starting point for clinical studies.Graphical Abstract

Plastic bronchitis is a rare and potentially life-threatening disease characterized by the development of obstructive fibrinous tracheobronchial casts and hypoxic respiratory failure. With its poorly understood cause and rare occurrence in the adult population, few treatment strategies have been described in adults with this condition. In this report, we present a case of successful treatment of an adult with plastic bronchitis, using thoracic duct ligation and resulting in full resolution of airway cast development.

Petite Integration Factor 1 (PIF1) is a multifunctional helicase present in nuclei and mitochondria. PIF1 knock out (KO) mice exhibit accelerated weight gain and decreased wheel running on a normal chow diet. In the current study, we investigated whether Pif1 ablation alters whole body metabolism in response to weight gain. PIF1 KO and wild type (WT) C57BL/6J mice were fed a Western diet (WD) rich in fat and carbohydrates before evaluation of their metabolic phenotype. Compared with weight gain-resistant WT female mice, WD-fed PIF1 KO females, but not males, showed accelerated adipose deposition, decreased locomotor activity, and reduced whole-body energy expenditure without increased dietary intake. Surprisingly, PIF1 KO females did not show obesity-induced alterations in fasting blood glucose and glucose clearance. WD-fed PIF1 KO females developed mild hepatic steatosis and associated changes in liver gene expression that were absent in weight-matched, WD-fed female controls, linking hepatic steatosis to Pif1 ablation rather than increased body weight. WD-fed PIF1 KO females also showed decreased expression of inflammation-associated genes in adipose tissue. Collectively, these data separated weight gain from inflammation and impaired glucose homeostasis. They also support a role for Pif1 in weight gain resistance and liver metabolic dysregulation during nutrient stress.

Background-Live donor kidney transplantation (LDKT) remains underutilized, partly due to the challenges many patients face in asking someone to donate. Actual and perceived kidney transplantation (KT) knowledge are potentially modifiable factors that may influence this process. Therefore, we sought to explore the relationships between these constructs and the pursuit of LDKT.