Safety and efficacy of repetitive stimulation of the left dorsolateral prefrontal cortex using transcranial focused ultrasound in treatment-resistant depressed patients: A non-inferiority randomized controlled trial protocol.

BACKGROUND: About 30% of patients diagnosed with major depressive disorder fail with the mainstream pharmacological treatment. Patients who do not achieve clinical remission of symptoms, even with two different antidepressants, are classified with treatment-resistant depression (TDR). This condition imposes an additional burden with increased Disability Adjusted Life Years. Therefore, complementary treatments, such as neuromodulation, are necessary. The transcranial focused ultrasound (tFUS) has emerged in the past few years as a reliable method for non-invasive neuromodulation in humans and may help treat TRD. This study aims to propose a research protocol for a non-inferiority randomized clinical trial of TDR with tFUS. METHODS: Patients with documented TRD will be screened upon entering the TRD outpatient clinic at UFMG (Brazil). One hundred patients without a clinical history of other psychiatric illness, anatomical abnormalities on magnetic resonance imaging (MRI), or treatment with electroconvulsive therapy will be invited to participate. Patients will be randomized (1:1) into two groups: 1) treatment with a previously established protocol of transcranial magnetic stimulation; and 2) treatment with a similar protocol using the stimulation. Besides regular consultations in the outpatient clinic, both groups will attend 7 protocolled spaced days of brain stimulation targeted at the left dorsolateral prefrontal cortex. They will also be submitted to 4 sessions of image studies (2 MRIs, 2 positron-emission tomography), 3 of neuropsychological assessments (at baseline, 1 week and 2 months after treatment), the Montgomery-Åsberg Depression Rating Scale to analyze the severity of depressive symptoms. DISCUSSION: This clinical trial intends to verify the safety and clinical efficacy of tFUS stimulation of the dorsolateral prefrontal cortex of patients with TRD, compared with a previously established neuromodulation method.

Millipore xMap® Luminex (HATMAG-68K): An Accurate and Cost-Effective Method for Evaluating Alzheimer's Biomarkers in Cerebrospinal Fluid.

Background: Alzheimer's disease (AD) biomarkers are of great relevance in clinical research, especially after the AT(N) framework. They enable early diagnosis, disease staging and research with new promising drugs, monitoring therapeutic response. However, the high cost and low availability of the most well-known methods limits their use in low and medium-income countries. In this context, Millipore xMap® Luminex may be a cost-effective alternative. In our study, using INNOTEST® as reference, we assess the diagnostic accuracy of Millipore xMap® and propose a cutoff point for AD. Methods: We performed lumbar puncture of seven older individuals with clinically defined AD, 17 with amnestic mild cognitive impairment (aMCI) and 11 without objective cognitive impairment-control group (CG). Cerebrospinal fluid (CSF) biomarkers concentrations for aB42, p-Tau, and t-Tau were measured by INNOTEST® and Millipore xMap®, and then the techniques were compared to assess the diagnostic accuracy of the new test and to define a cutoff. Results: INNOTEST® and Millipore xMap® measurements showed all correlations >0.8 for the same biomarker, except for t-Tau that was 0.66. Millipore xMap® measurements showed a robust accuracy for all biomarkers, with AUC higher than 0.808 (t-Tau), and the best for Aß42 (AUC = 0.952). The most accurate cutoffs were found at 1012.98 pg/ml (Aß42), 64.54 pg/ml (p-tau), 3251.81 pg/ml (t-tau), 3.370 (t-Tau/Aß42), and 0.059 (p-Tau/Aß42). Conclusion: Given its good accuracy and cost-effectiveness, Milliplex xMap® tests seems a reliable and promising tool, especially for low and middle-income countries.