Structural and functional characterization of the IgSF21-neurexin2α complex and its related signaling pathways in the regulation of inhibitory synapse organization.

The prevailing model behind synapse development and specificity is that a multitude of adhesion molecules engage in transsynaptic interactions to induce pre- and postsynaptic assembly. How these extracellular interactions translate into intracellular signal transduction for synaptic assembly remains unclear. Here, we focus on a synapse organizing complex formed by immunoglobulin superfamily member 21 (IgSF21) and neurexin2α (Nrxn2α) that regulates GABAergic synapse development in the mouse brain.

Selective incorporation of 5-hydroxytryptophan blocks long range electron transfer in oxalate decarboxylase.

Oxalate decarboxylase from Bacillus subtilis is a binuclear Mn-dependent acid stress response enzyme that converts the mono-anion of oxalic acid into formate and carbon dioxide in a redox neutral unimolecular disproportionation reaction. A π-stacked tryptophan dimer, W96 and W274, at the interface between two monomer subunits facilitates long-range electron transfer between the two Mn ions and plays an important role in the catalytic mechanism. Substitution of W96 with the unnatural amino acid 5-hydroxytryptophan leads to a persistent EPR signal which can be traced back to the neutral radical of 5-hydroxytryptophan with its hydroxyl proton removed.

Substitution of the sole tryptophan of the cupredoxin, amicyanin, with 5-hydroxytryptophan alters fluorescence properties and energy transfer to the type 1 copper site.

Amicyanin is a type 1 copper protein with a single tryptophan residue. Using genetic code expansion, the tryptophan was selectively replaced with the unnatural amino acid, 5-hydroxytryptophan (5-HTP). The 5-HTP substituted amicyanin exhibited absorbance at 300-320 nm, characteristic of 5-HTP and not seen in native amicyanin.

Oxalate decarboxylase uses electron hole hopping for catalysis.

The hexameric low-pH stress response enzyme oxalate decarboxylase catalyzes the decarboxylation of the oxalate mono-anion in the soil bacterium Bacillus subtilis. A single protein subunit contains two Mn-binding cupin domains, and catalysis depends on Mn(III) at the N-terminal site. The present study suggests a mechanistic function for the C-terminal Mn as an electron hole donor for the N-terminal Mn.

Diversity of structures and functions of oxo-bridged non-heme diiron proteins.

Oxo-bridged diiron proteins are a distinct class of non-heme iron proteins. Their active sites are composed of two irons that are coordinated by amino acid side chains, and a bridging oxygen that interacts with each iron. These proteins are members of the ferritin superfamily and share the structural feature of a four α-helix bundle that provides the residues that coordinate the irons.

Explanatory multivariate modeling for disability, pain, and claims in patients with spine pain via a physical therapy direct access model of care.

Background: Direct access physical therapy (DAPT) may result in improved patient outcomes and reduced healthcare costs. Prognostic factors associated with spine-related outcomes and insurance claims with DAPT are needed.

Objective: To identify factors that predict variations in outcomes for spine pain and insurance claims using DAPT.

Lumbar hernia after iliac crest bone harvest.

A lumbar hernia is a rare occurrence, with about 300 cases reported in the literature since the first publication by Garengeot in 1731. Incisional lumbar hernias are defined as secondary acquired hernias that can develop after surgeries such as nephrectomies or aortic aneurysm repairs. Harvesting bone from the iliac crest also has been identified as a cause of incisional lumbar hernias, occurring after about 0.

Dorsal Scapular Artery Variations and Relationship to the Brachial Plexus, and a Related Thoracic Outlet Syndrome Case.

 Knowledge of the relationship of the dorsal scapular artery (DSA) with the brachial plexus is limited.  We report a case of a variant DSA path, and revisit DSA origins and under-investigated relationship with the plexus in cadavers.  The DSA was examined in a male patient and 106 cadavers.