Deep phenotyping of post-infectious myalgic encephalomyelitis/chronic fatigue syndrome

Post-infectious myalgic encephalomyelitis/chronic fatigue syndrome (PI-ME/CFS) is a disabling disorder, yet the clinical phenotype is poorly defined, the pathophysiology is unknown, and no disease-modifying treatments are available. We used rigorous criteria to recruit PI-ME/CFS participants with matched controls to conduct deep phenotyping. Among the many physical and cognitive complaints, one defining feature of PI-ME/CFS was an alteration of effort preference, rather than physical or central fatigue, due to dysfunction of integrative brain regions potentially associated with central catechol pathway dysregulation, with consequences on autonomic functioning and physical conditioning. Immune profiling suggested chronic antigenic stimulation with increase in naïve and decrease in switched memory B-cells. Alterations in gene expression profiles of peripheral blood mononuclear cells and metabolic pathways were consistent with cellular phenotypic studies and demonstrated differences according to sex. Together these clinical abnormalities and biomarker differences provide unique insight into the underlying pathophysiology of PI-ME/CFS, which may guide future intervention.

When Zebras Collide: A Case of Synchronous Wolff-Parkinson-White Syndrome and Pheochromocytoma

Patient: Male, 36-year-old

Final Diagnosis: Pheochromocytoma

Symptoms: Chest discomfort • headache • shortness of breath • symptomatic tachyarrhythmia

Medication: —

Clinical Procedure: —

Specialty: General and Internal Medicine

204 Efficient editing of porcine parthenogenetic zygotes by electroporation of Cas9 ribonucleoprotein complexes

Gene editing by microinjection is an efficient system to produce mutant livestock; however, microinjection is time-consuming and requires special skill, limiting its use for large-scale production of gene-edited animals. Therefore, the aim of this study was to develop a system to deliver guide (g)RNA/Cas9/ribonucleoprotein (RNP) by electroporation into parthenogenic porcine zygotes. For experiment 1, we delivered gRNA/Cas9 RNP (250ng μL−1 of each), targeting GATA4 using 2 electroporation conditions. Group 1 (n=130): 20V, 3ms, ×2 pulses, 1 repeat; group 2 (n=102): 20V, 1ms, ×2 pulses, 2 repeats; and Control (n=96): parthenogenic zygotes, no electroporation. For experiment 2, we delivered gRNA/Cas9 RNP (250ng μL−1 of each) targeting ROSA26 by electroporation with 4 conditions compared with delivery of RNP by microinjection: group 1 (n=17): 20V, 3ms, ×1 pulses, 1 repeat; group 2 (n=49): 20V, 3ms, ×3 pulses, 1 repeat; group 3 (n=64): 30V, 3ms, ×1 pulses, 1 repeat; group 4 (n=61): 30V, 3ms, ×3 pulses, 1 repeat; group 5 (n=120): zygotes microinjected with Cas9/ROSA26 sgRNA (25/25ng μL−1), and Control (n=76): parthenogenic zygotes, no electroporation. The electroporated zygotes were cultured in porcine zygote medium-3 (PZM-3) with controlled atmosphere, and development was evaluated on Day 2 (cleavage) and Day 7 (blastocyst rate). Gene editing was evaluated on embryos (blastocyst and morulas) by PCR and Sanger sequencing of amplicons including the RNP target site. Data were compared using chi-squared test, and differences were considered significant at P<0.05. Cleavage rates in experiment 1 were similar for the control (86/96; 89.5%), group 1 (94/102; 92.1%), and group 2 (119/130; 91.5%). Blastocyst rates were higher for the control (46/96; 47%) than for the other groups (P<0.01). However, for the treated groups, the blastocyst rates were similar, group 1 (19/102; 9.2%) and group 2 (12/130; 18.6%). Furthermore, the non-homologous end joining (NHEJ) efficiency was similar for groups 1 (14/18; 77.7%) and 2 (14/17; 82.3%). In experiment 2, the cleavage (53/76; 69%) and blastocyst rates (30/76; 39%) were significantly higher for the control than for the treated groups (P<0.01). Among the groups, the lower cleavage and blastocyst rates were for group 4 (20/61; 32.7% and 3/61; 4.9%, respectively) compared with the other electroporation and microinjection groups (P<0.03). However, NHEJ efficiency was higher for electroporation groups 2 (6/8; 75%), 3 (17/17; 100%), and 4 (2/2; 100%) compared with microinjection (2/15; 13%). In conclusion, electroporation of Cas9/RNP is an efficient alternative to microinjection for gene editing in porcine zygotes.