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Summary Neurogenic thoracic outlet syndrome (NTOS) is the most common type of TOS. Typically it results from impingement of the neurovasculature as it passes between the anterior and middle scalene muscles; this classic anatomical relationship being the foundation of clinical diagnosis. Positional testing relies on vascular compromise occurring when the subclavian artery is compressed in this space. This study describes several anatomical variations observed in this relationship. Sixty-five cadavers (35m/30f) were assessed to determine the frequency and extent of brachial plexus branching variants. A total of thirty-one variations from “classic” anatomy were observed (47.7%). In two specimens (3.1%), the entire superior trunk coursed completely anterior to the anterior scalene in a position of relative vulnerability. In 27 instances, a portion of or the entire superior trunk pierced the anterior scalene muscle, and in two, the middle trunk also pierced the muscle belly. Interestingly, while two bilateral branching variations were observed, the majority occurred unilaterally, and almost exclusively on the left side. There were no sex differences in frequency. The high frequency of these variations and their potential to predispose patients to neurogenic TOS suggest that current diagnostic methods may be insufficient in clinical diagnosis. Due to lack of vascular compromise, patients with the piercing variant would not display positive signs on the traditional positional tests. The use of ultrasound to determine the route of the brachial plexus could determine whether this variation is present in patients who suffer from TOS symptoms but lack a diagnosis based on traditional positional testing. [ABSTRACT FROM AUTHOR]

Cytosolic calcium influx activates signaling pathways known to support pancreatic beta cell function and survival by modulating gene expression. Impaired calcium signaling leads to decreased beta cell mass and diabetes. To appreciate the causes of these cytotoxic perturbations, a more detailed understanding of the relevant signaling pathways and their respective gene targets is required. In this study, we examined the calcium-induced expression of the cytoprotective beta cell transcription factor Npas4. Pharmacological inhibition implicated the calcineurin, Akt/protein kinase B, and Ca2/ calmodulin-dependent protein kinase signaling pathways in the regulation of Npas4 transcription and translation. Both Npas4 mRNA and protein had high turnover rates, and, at the protein level, degradation was mediated via the ubiquitinproteasome pathway. Finally, beta cell cytotoxicity of the calcineurin inhibitor and immunosuppressant tacrolimus (FK-506) was prevented by Npas4 overexpression. These results delineate the pathways regulating Npas4 expression and stability and demonstrate its importance in clinical settings such as islet transplantation. [ABSTRACT FROM AUTHOR]

Roundup herbicides, with glyphosate as their active ingredient, are used in agriculture, forestry management, horticulture and in urban settings. When exposed to Roundup formulations and glyphosate, worms endure a suite of sublethal changes, potentially impacting their ability to provide ecosystem services. Roundup applications also impact soil microbes, which aid soil in delivering ecosystem services. The experiment described here sought to establish the length of time needed between herbicide application and earthworm and soil microbe recovery. We found that exposing worms and soil microbes to a Roundup formulation commonly used in urban settings, at about twice the recommended dose, did not impact earthworm mortality or body mass. However, worms significantly decreased their stress-test survival time, and soil microbes significantly declined in biomass after exposure. While worms demonstrated the strongest decline one-week post exposure, and soil microbes demonstrated the strongest decline two-weeks post exposure, both worms and soil microbes recovered by the third week. Roundup applications can potentially be timed so as to maximize the probability that soil-dwelling organisms remain unharmed by contamination. Unlabelled Image • Roundup® contamination reduced worm stress test survival time at Weeks 1 and 2. • Roundup® contamination caused soil microbe biomass to drop significantly in Week 2. • Worms and microbes recovered from exposure to Roundup® contamination by Week 3. • Roundup® contamination at double the label dose did not cause worm mortality. • Roundup® contamination at double the label dose did not reduce worm body mass. [ABSTRACT FROM AUTHOR]