A novel electrochemical immunosensor for the detection of matrix metalloproteinase-3 (MMP-3), a cancer biomarker protein, based on vertically aligned single-wall carbon nanotube (SWCNT) arrays is presented. Detection was based on a sandwich immunoassay consisting of horseradish peroxidase (14-16 labels) conjugated to a secondary antibody and/or a polymer bead loaded with multi-enzyme labels. Performance was optimized by effective minimization of non-specific binding (NSB) events using Bovine serum albumin (BSA), Tween-20 and optimization of the primary antibody and secondary antibody concentrations. Results provided a detection limit of 0.4 ng mL −1 (7.7 pM) for the 14-16 label sensor protocol and 4 pg mL −1 (77 fM) using a multiply enzyme labeled polymeric bead amplification strategy in 10 μL of calf serum. This immunosensor based on SWCNT arrays offers great promise for a rapid, simple, cost-effective method for clinical screening of cancer biomarkers for point-of-care diagnosis.

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OBJECTIVE Tourette syndrome (TS) is a complex neuropsychiatric disorder characterized by multiple motor and phonic tics. While pharmacological and behavioral therapy can be effective in most patients, a subset of patients remains refractory to treatment. Increasing clinical evidence from multiple centers suggests that deep brain stimulation (DBS) of the medial thalamus can be effective in many cases of refractory TS. METHODS The authors retrospectively reviewed outcomes in 13 patients with refractory TS who underwent medial thalamic DBS performed by their team over a 7-year period. Patients were evaluated by a multidisciplinary team, and preoperative objective assessments were performed using the Yale Global Tic Severity Scale (YGTSS) and Yale-Brown Obsessive Compulsive Scale. YGTSS scores were calculated at visits immediately postoperatively and at the most recent follow-up in patients with a minimum of 6 months of postoperative follow-up. Coordinates of the active DBS contacts were calculated and projected onto each patient's pre- and postoperative images. RESULTS Patients showed an average decrease of 37% (p = 0.0063) in the total tic severity at their first postoperative visit. At their latest visit, their scores achieved significance, decreasing from preoperative scores by an average of 50% (p = 0.0014). The average position of the active contact was noted to be at the junction of the posterior ventralis oralis internus/centromedian-parafascicular nuclei. Device-related complications occurred in 2 patients, necessitating additional surgeries. All patients continued to use the system at last follow-up. CONCLUSIONS The authors' data are consistent with the small but growing body of literature supporting DBS of the ventralis oralis internus/centromedian-parafascicular thalamus as an effective and relatively safe treatment for severe, refractory TS.

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A sensitive hydrogen peroxide sensor based on horseradish peroxidase covalently attached to layered nonoriented MWNTs modified electrode is presented. Cyclic voltammetry results gave quasi-reversible Fe III /Fe II voltammetry. The electron transfer rate constant (k s ) and Michaelis -Menten constant (K M ) in pH 7 is 48.8 AE 0.9 s À1 and 0.13 AE 0.05 mM respectively. A linear calibration curve for hydrogen peroxide was obtained up to 120 nM under the optimized conditions with a remarkable detection limit of (S/N ¼ 3) 1.5 nM. Results suggest that the nonoriented nanotubes act as electrical conductors and may also provide large surface area facilitating facile electron transfer and excellent electrochemical catalysis.