Engagement in Free Open Access Medical Education by US Nephrology Fellows

BACKGROUND

As free open access medical education (FOAMed) use increases, it is important to characterize how and why learners are using this educational material in nephrology. We describe the frequency, purpose, and type of FOAMed usage across US nephrology fellows.

METHODS

In this cross-sectional survey, items were emailed to all US adult and pediatric nephrology fellows via the American Society of Nephrology (ASN) Fellow Survey in May 2022. The eight-item survey, developed to measure FOAMed engagement, had previously undergone instrument validation. The results were analyzed by descriptive statistics.

RESULTS

In total, 43% (359/842) adult nephrology fellows and 51% (45/88) pediatric nephrology fellows completed the survey. Seventy-four percent (300/404) of fellows reported using FOAMed, and 72% (215/300) started using FOAMed within the past 2 years. Of FOAMed users, 41% (122/300) reported viewing FOAMed and 33% (99/300) reported applying knowledge gained from these resources daily or weekly. Common purposes for FOAMed engagement included searching Twitter to learn about others' opinions in the field (43%; 130/300), reading blogs to answer clinical questions (35%; 105/300), and listening to podcasts for the most up-to-date information (39%; 116/300). Compared with traditional educational resources, fellows preferred using FOAMed for staying up to date on nephrology topics (75%) and answering clinical questions (37%). Among all fellows, the greatest barriers to FOAMed use were unfamiliarity with FOAMed (27%; 111/404), validity concerns (22%; 90/404), and a lack of a local community of FOAMed users (22%; 87/404).

CONCLUSIONS

Seventy-four percent of nephrology fellows used FOAMed resources in a variety of ways, and of them, 33% of fellows clinically applied knowledge gained from these resources. Reasons for engaging with FOAMed varied across resources.

Mutant IDH1 Downregulates ATM and Alters DNA Repair and Sensitivity to DNA Damage Independent of TET2

Mutations in the isocitrate dehydrogenase-1 gene (IDH1) are common drivers of acute myeloid leukemia (AML) but their mechanism is not fully understood. It is thought that IDH1 mutants act by inhibiting TET2 to alter DNA methylation, but there are significant unexplained clinical differences between IDH1- and TET2-mutant diseases. We have discovered that mice expressing endogenous mutant IDH1 have reduced numbers of hematopoietic stem cells (HSCs), in contrast to Tet2 knockout (TET2-KO) mice. Mutant IDH1 downregulates the DNA damage (DD) sensor ATM by altering histone methylation, leading to impaired DNA repair, increased sensitivity to DD, and reduced HSC self-renewal, independent of TET2. ATM expression is also decreased in human IDH1-mutated AML. These findings may have implications for treatment of IDH-mutant leukemia.

Variability in platelet- and collagen-binding defects in type 2M von Willebrand disease

Type 2M von Willebrand disease (VWD) includes qualitative defects in von Willebrand factor (VWF) function, with normal multimer distribution but a defect in VWF activity with respect to platelet or collagen binding. We characterized novel VWF gene mutations found in type 2M VWD subjects enrolled in the Zimmerman Program for the Molecular and Clinical Biology of VWD. Subjects were enrolled based on a pre-existing diagnosis of type 2M VWD. Testing included full-length gene sequencing, VWF antigen (VWF:Ag), VWF ristocetin cofactor activity (VWF:RCo), VWF collagen binding and multimer distribution. Recombinant VWF variants were synthesized using site-directed mutagenesis and expressed in HEK293T cells. Platelet binding was measured by flow cytometry with fixed platelets and ELISA with recombinant glycoprotein Ibα (GPIbα). Four novel VWF A1 domain mutations were found in individuals with type 2M VWD: S1358N, S1387I, S1394F and Q1402P. All subjects had a history of bleeding, VWF:RCo < 40 IU dL(-1) , VWF:RCo/VWF:Ag ratios <0.6 and normal multimer distribution. No defect in expression, secretion, or multimerization was found for any of the mutations. All showed decreased binding to intact platelets, and decreased or absent binding to a mutant GPIbα construct with spontaneous VWF binding. 1387I had decreased binding to all collagen types tested. 1402P had reduced binding exclusively to type VI collagen. Type 2M VWD is a heterogeneous category comprised of both collagen- and platelet-binding defects. Understanding the precise defect for each mutation may ultimately lead to better diagnosis and treatment.

Efficacy of a p38 mitogen activated protein kinase inhibitor in mitigating an established inflammatory reaction to polyethylene particles in vivo

The inhibitor of p38 mitogen-activated protein kinase (MAPK) is of interest in the nonoperative treatment of periprosthetic osteolysis due to wear particles. Previous studies demonstrated that an oral p38 MAPK inhibitor did not suppress bone formation when given during the initial phase of tissue differentiation. However, the oral p38 MAPK inhibitor also did not curtail the foreign body and chronic inflammatory response to particles when given simultaneously. The purpose of the current study was to examine the efficacy of a p38 MAPK inhibitor, SCIO-323, on mitigating an established inflammatory reaction that parallels the clinical situation more closely. The Bone Harvest Chamber was implanted in rabbits and submicron polyethylene particles were placed in the chamber for 6 weeks. The contents of the chambers were harvested every 6 weeks. Oral treatment with the SCIO-323 included delivery for 3 weeks and stopping for 3 weeks, delivery for 3 weeks after an initial 3-week delay, and delivery for 6 weeks continuously. Administration of the SCIO-323 continuously for 6 weeks with/without the presence of particles, or for the initial 3 of 6 weeks had minor effects on bone ingrowth. After establishing a particle-induced chronic inflammatory reaction for 3 weeks, administration of SCIO-323 for a subsequent 3 weeks suppressed net bone formation. The activity of osteoclast-like cells remained low among all treatments when compared with the first control. Using the present model, the oral p38 MAPK inhibitor was ineffective in improving bone ingrowth in the presence of polyethylene particles.

Effects of local infusion of OP-1 on particle-induced and NSAID-induced inhibition of bone ingrowth in vivo

Excessive polyethylene wear particles from joint replacements may lead to periprosthetic osteolysis and loosening. Nonsteroidal anti-inflammatory drugs (NSAIDs) decrease fracture healing and bone ingrowth. We hypothesized that continuous local infusion of OP-1 (BMP-7) would increase local bone formation in the presence of two different adverse stimuli, polyethylene particles, and an oral NSAID. The Drug Test Chamber (DTC) was implanted in the proximal tibia of mature rabbits. The tissue growing into the chamber was exposed to OP-1 solution (110 ng/day), which was infused via an osmotic pump. Infusion of OP-1 alone for 6 weeks enhanced local bone formation in the chamber by 80% (p < 0.05) over infusion of carrier alone. In the presence of polyethylene particles, infusion of OP-1 increased local bone formation by 38% (p < 0.05) over treatment with particles and carrier. Oral administration of NSAID reduced local bone formation by 58% (p < 0.05); this suppressive effect caused by NSAIDS was completely reversed by the infusion of OP-1 (p < 0.05). These findings underline a potential role for local treatment with OP-1 to increase bone formation in the presence of potentially adverse stimuli such as polyethylene wear particles or NSAID use.

High-resolution transient-double-resonance spectroscopy in SF6

Four distinct collisionless excitation processes are observed when SF(6) molecules are illuminated simultaneously by "weak" continuously tunable cw probe radiation and by "strong" pulsed-pump radiation. These processes are identified by studying the line shape, frequency, and temporal decay of the change in transmitted probe intensity induced by the pump pulse. The significance of this work for the spectroscopy of high vibrational levels and for collisionless dissociation is discussed briefly.