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The use of photothermal processes has been proven effective in the control of microbial infections. Simultaneously, the localized surface plasmon resonance phenomena in metallic nanoparticles have been explored as an alternative strategy to achieve highly efficient localized heating. In this work, we propose the use of selected nanoheaters to improve the efficiency of fungal photothermal inactivation of Candida albicans through size optimization of plasmonic gold nanorods. Here, the optical heating of polyethylene glycol coated gold nanorods of varying sizes is evaluated, both theoretically and experimentally. A size-dependent computational approach was applied to identify metallic nanorods with maximized thermal performance at 800 nm, followed by the experimental comparison of optimal and suboptimal nanoheaters. Comparison among samples show temperatures of up to 53.0 °C for 41×10 nm gold nanorods against 32.3 °C for 90×25 nm, a percentage increase of ∼63% in photothermal inactivation assessments. Our findings reveal that gold nanorods of 41×10 nm exhibit superior efficiency in near-infrared (800 nm) photothermal inactivation of fungi, owing to their higher light-thermal conversion efficiency. The identification of high performance metallic nanoheaters may lead to the reduction of the nanoparticle dose used in plasmonic-based procedures and decrease the laser exposure time needed to induce cell death. Moreover, our results provide insights to better exploit plasmonic nanoparticles on photothermal inactivation protocols., (Copyright © 2024. Published by Elsevier B.V.)

Objective: To investigate mirror activity in amyotrophic lateral sclerosis (ALS) patients, using a simple paradigm of signal quantification., Methods: Patients were asked to perform a brief isometric maximum contraction of the abductor digiti minimi (ADM) or tibialis anterior (TA) on one side, while relaxing the contralateral side of the body. Both sides were investigated. Signals were stored and analyzed offline, for quantification of electromyographic signal. Clinical signs of upper motor neuron (UMN) dysfunction, transcranial magnetic stimulation (TMS) for the upper (UL) and lower limbs (LL), the ADM ipsilateral cortical silent period (iSP) and the Edinburgh Cognitive and Behavioral ALS Screen (ECAS) cognitive scale were also investigated., Results: 42 ALS patients were included. In the 4 investigated muscles the amount of mirror activity was significantly higher than in the matched healthy group. The amount of mirror activity was similar between sides, but significantly higher in UL and LL with abnormal TMS results for ADM (p = 0.005) and TA (p = 0.002), as well as in UL with abnormal iSP values (p = 0.009). No association was found between mirror activity and clinical signs of UMN involvement., Conclusions: Mirror activity is a common phenomenon in ALS. Mirror activity intensity corresponds to the severity of UMN dysfunction, as measured by TMS, and probably derives from the abnormal transcallosal inhibition as mirrored by iSP abnormality., Significance: Mirror activity is increased in ALS and is associated with abnormal transcallosal inhibition and UMN dysfunction., (Copyright © 2023 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

We analyze markers of carnitine insufficiency and deficiency, lysine (LYS) and methionine (MET), in 39 neonates with intrapartum hypoxia (selection criteria: umbilical artery pH <7.20, lactate >1.8 mmol/l and PaO2 <25 mm Hg), and in 35 healthy newborn infants (control group) in the early neonatal period (1-7 days of life). Free (FC), total (TC) carnitine and acylcarnitines (AC=short-chain+long-chain acylcarnitines) were measured using a radioisotopic micromethod; LYS and MET were determined by high-pressure liquid chromatography. AC and TC plasma concentrations and AC/FC ratio were higher while FC/TC ratio was lower in the hypoxic neonates than in the control group. Hypoxic newborn infants (59%) presented "carnitine deficiency" (FC/TC <0.7) and 60% of them "carnitine insufficiency" (AC/FC ratio >0.4) vs. 31% and 28%, respectively, for the neonates of the control group (p<0.05). In the healthy neonates group, MET correlated with FC/TC and the AC/FC ratio. FC, TC, AC, AC/FC and umbilical artery pH (pHua) were inversely correlated. FC/TC and MET correlated with pHua. We conclude that: (1) an important percentage of newborn infants with intrapartum hypoxia suffer carnitine deficiency and carnitine insufficiency in the early neonatal period, related to MET plasma levels; (2) the carnitine deficiency or insufficiency in the neonate is determined by the degree of intrapartum acidosis.