Waxy fingers and skin tethering.

The patient sought care for a burn he hadn't felt when he'd held a hot cup of coffee. His history, and the appearance of his hands, suggested a systemic disease at work.

Double Distal Intraneural Fascicular Nerve Transfers for Lower Brachial Plexus Injuries.

PURPOSE: To evaluate outcomes following transfer of the supinator motor branch of the radial nerve (SMB) to the posterior interosseous nerve (PIN) and the pronator teres motor branch of median (PTMB) to the anterior interosseous nerve (AIN) in patients with lower brachial plexus injuries. METHODS: Since December 2010, 4 patients have undergone combined transfer of the SMB to PIN and PTMB to AIN for lower brachial plexus palsies. The study was prospectively designed, and the patients were followed for 4 years to monitor their functional improvement. RESULTS: One patient failed to return after his 4-month postoperative visit. The other 3 patients all regained M4 thumb and finger extension, and 2 recovered M4 thumb and finger flexion at the final evaluation, a mean 30 months after the nerve transfer surgeries. CONCLUSIONS: Combined transfer of the SMB to PIN and PTMB to AIN may lead to successful recovery of digital extrinsic flexion and extension in lower brachial plexus injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Involvement of TRP channels in the CO2 chemosensitivity of locus coeruleus neurons.

Catecholaminergic neurons in the locus coeruleus (LC) play a role in the ventilatory response to hypercapnia. Here, we show evidence for the involvement of transient receptor potential (TRP) channels. We found that the input resistance was reduced during an exposure to 8% CO(2) in ~35% LC neurons in mouse brain slices, accompanied by depolarization and higher firing activity. The neuronal responses suggest the opening of Na(+) or nonselective cationic channels instead of the closure of K(+) channels. As a major group of cationic channels, the TRP channels are expressed in the brain, some of which are activated by acidic pH. We therefore screened all representative TRP channels using the quantitative real-time PCR analysis. High levels of mRNA expression of TRPC5, TRPM2, and TRPM7 were found in the LC tissue. Of them, the TRPC5 transcript was the most abundant. The TRPC5 channel was activated by extracellular acidification when expressed in human embryonic kidney (HEK) cells. The TRPC5 currents started to be activated at pH 7.4 with pKa 6.9. The TRPC5 currents were also activated by isohydric hypercapnic and intracellular acidosis in a Ca(2+)-dependent manner. Consistently, the LC neurons were stimulated by both extra- and intracellular acidosis. The stimulatory effect of hypercapnia on LC neurons was eliminated by selective TRPC inhibitor SKF-96365 with and without the blockade of synaptic transmission. Single-cell PCR analysis indicated that TRPC5 mRNAs existed in the LC neurons. Thus these results strongly suggest that the TRP channels are likely to play a role in the CO(2) chemosensitivity of LC neurons, especially TRPC5.