关键词： motor unit firing rates   NCV   cooling   neurological assessments  

摘要： Background: This study aimed to determine the effects of a standard therapeutic cooling protocol using crushed ice on the elbow to explore if changes in the motor unit (MU) firing rates in the first dorsal interosseous (FDI) muscle are comparable to known changes in sensory and motor nerve conduction velocity (NCV) due to a regional temperature drop around a peripheral nerve. Methods: Twelve healthy individuals were assessed before cooling, immediately after cooling, and 15 min of rewarming. Assessments included two standard non-invasive nerve conduction velocity tests and a non-invasive investigation of the MU firing rates using surface electromyography decomposition (dEMG). Results: Repeated ANOVAs showed significant differences in the MU firing rates and NCV between time points (p = 0.01 and p < 0.001). All measures showed significant differences between pre and post cooling and between pre-cooling and 15 min of passive re-warming, however, no changes were seen between post cooling and rewarming except in the sensory NCV, which increased but did not return to the pre-cooled state. Conclusions: This current study showed a significant, temporary, and reversible reduction in ulnar NCV across the elbow in healthy subjects, which was associated with a significant decrease in mean MU firing rates in the FDI muscle.

关键词： Cerebral blood flow   Cranioplasty   Decompressive craniectomy   Hemodynamics   Perfusion imaging   Transcranial Doppler sonography  

摘要： Background Early cranioplasty has been encouraged after decompressive craniectomy (DC), aiming to reduce consequences of atmospheric pressure over the opened skull. However, this practice may not be often available in low-middle-income countries (LMICs). We evaluated clinical improvement, hemodynamic changes in each hemisphere, and the hemodynamic balance between hemispheres after late cranioplasty in a LMIC, as the institution's routine resources allowed. Methods Prospective cohort study included patients with bone defects after DC evaluated with perfusion tomography (PCT) and transcranial Doppler (TCD) and performed neurological examinations with prognostic scales (mRS, MMSE, and Barthel Index) before and 6 months after surgery. Results A final sample of 26 patients was analyzed. Satisfactory improvement of neurological outcome was observed, as well as significant improvement in the mRS (p = 0.005), MMSE (p < 0.001), and Barthel Index (p = 0.002). Outpatient waiting time for cranioplasty was 15.23 (SD 17.66) months. PCT showed a significant decrease in the mean transit time (MTT) and cerebral blood volume (CBV) only on the operated side. Although most previous studies have shown an increase in cerebral blood flow (CBF), we noticed a slight and nonsignificant decrease, despite a significant increase in the middle cerebral artery flow velocity in both hemispheres on TCD. There was a moderate correlation between the MTT and contralateral muscle strength (r = - 0.4;p = 0.034), as well as between TCD and neurological outcomes ipsilateral (MMSE;r = 0.54, p = 0.03) and contralateral (MRS;p = 0.031, r = - 0.48) to the operated side. Conclusion Even 1 year after DC, cranioplasty may improve cerebral perfusion and neurological outcomes and should be encouraged.

关键词： Cerebrospinal fluid   free light chain   intrathecal IgG synthesis   oligoclonal bands  

摘要： The analysis of cerebrospinal fluid (CSF) is routinely used in the diagnostic work-up of a range of inflammatory, infective, and congenital neurological conditions. Many diagnostic tests used in this analysis have poor sensitivity;as such, we investigated the utility of CSF free light chain (FLC) analysis as an adjunct to currently used assays in a paediatric population with neurological disorders. Kappa (kappa) and lambda (lambda) FLC levels were quantitated in blinded CSF samples by two nephelometric platforms. Results were correlated to clinical diagnoses and classified according to inflammatory/infective or noninflammatory pathogenesis. FLC results were also compared to currently used CSF diagnostic tests including oligoclonal bands (OCB), CSF IgG and albumin levels, and differential cell count. Of 70 samples analysed, 29 (41%) had an inflammatory or infective diagnosis and 41 (59%) presented with a range of non-inflammatory aetiologies. Thirteen patients had elevated kappa FLC or lambda FLC as detected on the IMMAGE 800, defined as greater than the detection limit of the assay (0.600 mg/L for CSF kappa FLC, and 0.490 mg/L for CSF lambda FLC), and of these 12 (92%) had an inflammatory disease (sensitivity 41.4%, specificity 97.6%). On the BN II using optimal cut-offs of 0.27 mg/L and 0.12 mg/L for CSF kappa FLC and lambda FLC respectively, 24 (34%) patients had elevated results, of which 21 (88%) had an inflammatory disease (sensitivity 72.4%, specificity 92.7%). Analysis of FLC correlated better with diagnostic classification of the diseases than OCB, cell counts and CSF IgG levels. The results of this study support the use of CSF FLC analysis in the diagnosis of paediatric neuroinflammatory conditions.