The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus causing the coronavirus disease 2019 (COVID-19) pandemic is known to lead to the complicated sequelae of severe acute respiratory distress syndrome. Proning has been used as an adjunctive treatment to improve oxygenation in both ventilated and non-ventilated patients. Although patients respond well to this strategy, complications from this arise as well. It is hypothesized that COVID-19 intensive care unit (ICU) proned ventilation is associated with new cases of foot drops or compressive unilateral ankle dorsiflexion weakness during the early 2020 COVID-19 pandemic. Five patients presented to an acute rehabilitation facility with unilateral ankle dorsiflexion weakness after ICU proned ventilation during the COVID-19 pandemic. Three patients were found to have primarily subacute left sensory-motor dysmyelinating common peroneal neuropathies located around the fibular head. Two patients were found to have primarily subacute sensory-motor dysmyelinating right-sided common peroneal neuropathies above the fibular head and distal to biceps femoris muscle. Compressive unilateral common peroneal neuropathies during the pandemic are possibly related to the impromptu, unconventional, and unfamiliar use of proned ventilation.

Background Botulinum toxin injections are effective in relieving focal spasticity resulting from upper motor neuron injuries. Doses approved in the United States for onabotulinumtoxinA and incobotulinumtoxinA are up to 400 units, yet higher doses are often used. Objective To determine differences in risk of adverse events when using higher (>600 units) as compared to lower doses within clinically applicable categories; the difference in adverse events between types of botulinum toxin‐A, and any association of the injection of cervical muscles with increased risk for adverse events. Design and Setting Retrospective analysis of injections performed over a 3‐year period at a freestanding rehabilitation hospital network. Participants Persons with spasticity or dystonia undergoing ona‐ and/or incobotulinumtoxinA injections. Interventions Not applicable. Main Outcome Measures Adverse events for injections were divided into the three dose ranges (≤400 units, 401‐600 units, or > 600 units). Results 889 injections in 342 patients met inclusion criteria with 65% ≤400 units, 21% 401‐600 units, and 14% >600 units. Adverse events were not significantly increased in doses of 401‐600 units relative to ≤400 units (OR 0.97, 95% CI 0.31, 2.98). Doses of toxin over 600 units were associated with significantly increased relative risk of adverse events (OR 2.98, 95% CI 1.12, 8.13). There were no significant differences between adverse event rates for onabotulinumtoxinA or incobotulinumtoxinA (P >.99). Inclusion of cervical muscles in isolation did significantly increase the risk of adverse events (OR 4.21, 95% CI 1.15, 15.46). Conclusion Risk for adverse events were not significantly increased in doses of ona‐ and/or incobotulinumtoxinA up to 600 units, suggesting that the current 400 units upper bound of approved dose may need to be reexamined. Doses above 600 units were found to increase the rate of adverse effects and clinical benefit versus risk should be taken into account. Level of Evidence III.

Although cells of mushroom-producing fungi typically contain paired haploid nuclei (n + n), most Armillaria gallica vegetative cells are uninucleate. As vegetative nuclei are produced by fusions of paired haploid nuclei, they are thought to be diploid (2n). Here we report finding haploid vegetative nuclei in A. gallica at multiple sites in southeastern Massachusetts, USA. Sequencing multiple clones of a single-copy gene isolated from single hyphal filaments revealed nuclear heterogeneity both among and within hyphae. Cytoplasmic bridges connected hyphae in field-collected and cultured samples, and we propose nuclear migration through bridges maintains this nuclear heterogeneity. Growth studies demonstrate among- and within-hypha phenotypic variation for growth in response to gallic acid, a plant-produced antifungal compound. The existence of both genetic and phenotypic variation within vegetative hyphae suggests that fungal individuals have the potential to evolve within a single generation in response to environmental variation over time and space.

No abstract