Neurologic dysfunction and pancytopenia secondary to acquired copper deficiency following duodenal switch: case report and review of the literature.

The duodenal switch (DS) procedure is a type of restrictive-malabsorptive bariatric surgery that is typically reserved for severe morbidly obese people (body mass index >50 kg/m(2)) with obesity-related comorbidities, when diet, lifestyle changes, and pharmacologic therapy fail to achieve adequate weight loss. Patients who undergo the DS procedure are at risk for malabsorption, malnutrition, and nutrient deficiencies. Copper deficiency is a commonly reported long-term complication of Roux-en-Y gastric bypass (RYGB) surgery.

Regulation of neurexin 1beta tertiary structure and ligand binding through alternative splicing.

Neurexins and neuroligins play an essential role in synapse function, and their alterations are linked to autistic spectrum disorder. Interactions between neurexins and neuroligins regulate inhibitory and excitatory synaptogenesis in vitro through a "splice-insert signaling code." In particular, neurexin 1beta carrying an alternative splice insert at site SS#4 interacts with neuroligin 2 (found predominantly at inhibitory synapses) but much less so with other neuroligins (those carrying an insert at site B and prevalent at excitatory synapses).