Adaptive changes in group-II metabotropic glutamate receptors underlie the deficit in recognition memory induced by methamphetamine in mice.

Cognitive dysfunction is associated with methamphetamine use disorder. Here, we used genetic and pharmacological approaches to examine the involvement of either mGlu2 or mGlu3 receptors in memory deficit induced by methamphetamine in mice. Methamphetamine treatment (1 mg/kg, i.p., once a day for 5 days followed by 7 days of withdrawal) caused an impaired performance in the novel object recognition (NOR) test in wild-type mice, but not in mGlu2-/- or mGlu3-/- mice. Memory deficit in wild-type mice challenged with methamphetamine was corrected by systemic treatment with selectively negative allosteric modulators of mGlu2 or mGlu3 receptors (compounds VU6001966 and VU0650786, respectively). Methamphetamine treatment in wild-type mice caused large increases in levels of mGlu2/3 receptors, the type-3 activator of G protein signaling (AGS3), Rab3A and the vesicular glutamate transporter, vGlut1 in the prefrontal cortex (PFC). Methamphetamine did not alter mGlu2/3-mediated inhibition of cAMP formation, but abolished the ability of postsynaptic mGlu3 receptors to boost mGlu5 receptor-mediated inositol phospholipid hydrolysis in PFC slices. Remarkably, activation of presynaptic mGlu2/3 receptors did not inhibit, but rather amplified depolarization-induced [3H]-D-aspartate release in synaptosomes prepared from the PFC of methamphetamine-treated mice.These findings demonstrate that exposure to methamphetamine causes changes in the expression and function of mGlu2 and mGlu3 receptors, which might alter excitatory synaptic transmission in the PFC, and raise the attractive possibility that selective inhibitors of mGlu2 or mGlu3 receptors (or both) may be used to improve cognitive dysfunction in individuals affected by methamphetamine use disorder.Significance Statement Targeting cognitive dysfunction may reduce methamphetamine craving and relapse in individuals who use methamphetamine. Using the novel object recognition (NOR) test for the study of recognition memory we found that cognitive impairment caused by methamphetamine in mice was corrected by genetic deletion or selective pharmacological blockade of either mGlu2 or mGlu3 receptors, two metabotropic glutamate receptor subtypes that control synaptic activity by restraining glutamate release. Interestingly, mGlu2/3 receptors were up-regulated in the prefrontal cortex of methamphetamine-treated mice, and showed an inverse mode of operation by enhancing depolarization-induced glutamate release. These findings suggest that selective mGlu2 or mGlu3 receptor antagonists may improve cognitive function in individuals affected by methamphetamine use disorder.

Elite Soccer Players' Weekly Workload Assessment Through a New Training Load and Performance Score.

Purpose: Monitoring players' training load allows practitioners to enhance physical performance while reducing injury risk. The aim of this study was to identify the key external load indicators in professional U19 soccer. Methods: Twenty-four-professional Italian young (U19) soccer players were monitored by using the rating of perceived exertion (CR-10 RPE scale) and a wearable inertial sensor during the competitive season. Three main components were detected by a Principal Component Analysis (PCA): i) volume metabolic related component, ii) intensity mechanical stimuli component, and iii) intensity metabolic/mechanical component. We hence computed two scores (i.e. Performance [PERF] and total workload [WORK]) permitting to investigate the weekly microcycle. Results: Correlation analysis showed that scores (i.e. PERF and WORK) are low correlated (r = -0.20) suggesting that they were independent. Autocorrelation analysis showed that a weekly microcycle is detectable in all the scores. Two-way ANOVA RM showed a statistical difference between match day (MD) and playing position for the three PCA components and PERF score. Conclusion: We proposed an innovative approach to assess both the players' physical performance and training load by using a machine learning approach allowing reducing a large dataset in an objective way. This approach may help practitioners to prescribe the training in the microcycle based on the two scores.

Acute effects of prismatic adaptation on penalty kick accuracy and postural control in young soccer players: A pilot study.

Background: Prismatic adaptation (PA) is a visuomotor technique using prismatic glasses that are capable of moving the visual field and to affect the excitability of certain brain areas. The aim of this pilot study was to explore potential acute effects of PA on penalty kick accuracy and postural control in youth soccer players. Methods: In this randomized crossover study, seven young male soccer players performed three PA sessions (rightward PA, r-PA; leftward PA, l-PA; sham PA, s-PA) with a washout period of 1-week between them. Immediately before and after each PA session, penalty kick accuracy and postural control were assessed. Results: We detected an increase in penalty kick accuracy following PA, regardless of the deviation side of the prismatic glasses (F1,5 = 52.15; p = 0.08; ηp2 = 0.981). In detail, our results showed an increase in the penalty kick accuracy toward the right target of the football goal following r-PA and toward the left target of the football goal following l-PA. We detected a significant effect on the sway path length (F2,12 = 10.42; p = 0.002; ηp2 = 0.635) and the sway average speed (F2,12 = 9.17; p = 0.004; ηp2 = 0.605) parameters in the stabilometric test with open eyes following PA, regardless of the deviation side of the prismatic glasses. In detail, our results showed a significant difference in both the stabilometric parameters (p = 0.016 and p = 0.009, respectively) only following l-PA. Conclusion: The findings of this pilot study indicate that PA could positively affect penalty kick accuracy and postural control suggesting that PA could be used as a visual training technique in athletes.

Biodegradation of Polystyrene by Plastic-Eating Tenebrionidae Larvae.

Polystyrene (PS) is an extremely stable polymer with a relatively high molecular weight and a strong hydrophobic character that makes it highly resistant to biodegradation. In this study, PS was subjected to biodegradation tests by Tenebrio Molitor (T. Molitor) and Zophobas Morio (Z. Morio) larvae. Specifically, six different experimental diets were compared: (i) T. Molitor fed with bran; (ii) T. Molitor fed only PS; (iii) T. Molitor fed only PS treated with H2O2; (iv) Z. Morio fed with bran; (v) Z. Morio fed only PS; and (vi) Z. Morio fed only PS treated with H2O2. Therefore, the mass change of the larvae and the survival rate were measured periodically, while the frass collected after 15 and 30 days was analyzed by different analyses, such as spectroscopy (FTIR), spectrometry (molecular weight and polydispersity), thermal analysis (TGA) and microscopy (scanning electron microscopy observations). The obtained results suggest that in the case of T. Molitor larvae, larvae feeding on bran showed the highest survival rate of ~94% at 30 days, while in the case of the Z. Morio larvae, the highest survival rate was exhibited by larvae eating PS-H2O2. Although not strongly pronounced, the Mw and Mn of PS in the frass of both T. Molitor and Z. Morio larvae decreased over 30 days, suggesting PS biodegradation. Finally, the morphological analysis shows that PS samples isolated from the frass of T. Molitor and Z. Morio larvae showed completely different, rough and irregularly carved surface structures, in comparison to PS before biodegradation.

Telecoaching: a potential new training model for Charcot-Marie-Tooth patients: a systematic review.

Introduction: Charcot-Marie-Tooth disease (CMT) is an inherited neuropathy that affects the sensory and motor nerves. It can be considered the most common neuromuscular disease, with a prevalence of 1/2500. Methods: Considering the absence of a specific medical treatment and the benefits shown by physical activity in this population, a systematic review was completed using several search engines (Scopus, PubMed, and Web of Science) to analyze the use, effectiveness, and safety of a training program performed in telecoaching (TC). TC is a new training mode that uses mobile devices and digital technology to ensure remote access to training. Results: Of the 382 studies identified, only 7 met the inclusion criteria. The effects of a TC training program included improvements in strength, cardiovascular ability, and functional abilities, as well as gait and fatigue. However, the quality of the studies was moderate, the size of the participants in each study was small, and the outcome measured was partial. Discussion: Although many studies have identified statistically significant changes following the administration of the TC training protocol, further studies are needed, with appropriate study power, better quality, and a higher sample size.

Association between match-related physical activity profiles and playing positions in different tasks: A data driven approach.

Assessing the intensity characteristics of specific soccer drills (matches, small-side game, and match-based exercises) could help practitioners to plan training sessions by providing the optimal stimulus for every player. In this paper, we propose a data analytics framework to assess the neuromuscular or metabolic characteristics of a soccer-specific exercise in relation with the expected match intensity. GPS data describing the physical tasks' external intensity during an entire season of twenty-eight semi-professional soccer players competing at the fourth Italian division were used in this study. A supervised machine-learning approach was tested in order to detect difference in playing positions in different sport-specific drills. Moreover, a non-supervised machine-learning model was used to profile the match neuromuscular and metabolic characteristics. Players' playing positions during matches and match-based exercises are characterised by specific metabolic and neuromuscular characteristics related to tactical demands, while in the small-side game these differences are not detected. Additionally, our framework permits to evaluate if the match performance request is mirrored during training drills. Practitioners could evaluate the type of stimulus performed by a player in a specific training drill in order to assess if they reflect the matches characteristics of their specific playing position.

Applicability of the Cumberland Ankle Instability Tool in Elite Volleyball Athletes: A Cross-Sectional Observational Study.

BACKGROUND: The ease of administration of the Cumberland Ankle Instability Tool (CAIT) could represent a methodology for periodically evaluating athletes, preventing ankle instability injuries. This study aimed to achieve three objectives: (a) to evaluate the applicability of the CAIT scale in volleyball; (b) to explore whether ankle instability presents a greater risk in lower-level volleyball categories and whether elite athletes demonstrate an ability to mitigate this risk; and (c) to identify potential predictors of ankle instability. METHODS: Eighty female volleyball players participated in this cross-sectional observational study. The CAIT was administered to evaluate the athletes belonging to some teams in Series A, B, and C. RESULTS: The Spearman's ranks correlation coefficient showed significant correlations between CAIT items. Additionally, the Cronbach's α showed a high internal consistency. Our results showed a significant difference between athletes who reported pain and those who did not (p < 0.001). The multiple linear regression model analysis showed that pain was a predictor of ankle instability (p < 0.001). CONCLUSIONS: Our findings suggest that the CAIT can be used to evaluate ankle stability in volleyball players. This scale could represent a valuable tool for implementing specific intervention programs to prevent ankle injuries in athletes.

Metabotropic Glutamate Receptors Type 3 and 5 Feature the "NeuroTransmitter-type" of Glioblastoma: A Bioinformatic Approach.

BACKGROUND: Glioblastoma (GBM) represents an aggressive and common tumor of the central nervous system. The prognosis of GBM is poor, and despite a refined genetic and molecular characterization, pharmacological treatment is largely suboptimal. OBJECTIVE: Contribute to defining a therapeutic line in GBM targeting the mGlu3 receptor in line with the principles of precision medicine. METHODS: Here, we performed a computational analysis focused on the expression of type 3 and 5 metabotropic glutamate receptor subtypes (mGlu3 and mGlu5, respectively) in high- and low-grade gliomas. RESULTS: The analysis allowed the identification of a particular high-grade glioma type, characterized by a high expression level of both receptor subtypes and by other markers of excitatory and inhibitory neurotransmission. This so-called neurotransmitter-GBM (NT-GBM) also shows a distinct immunological, metabolic, and vascularization gene signature. CONCLUSION: Our findings might lay the groundwork for a targeted therapy to be specifically applied to this putative novel type of GBM.

Telecoaching as a new training method for elderly people: a systematic review.

BACKGROUND: The numerous restrictive measures implemented during the recent COVID-19 pandemic have reduced the levels of physical activity (PA) carried out by elderly people and telecoaching (TC) could be a training method to maintain the recommended levels of PA. In fact, TC uses information and digital communications technologies, such as computers and mobile devices, to access training services remotely. Thus, this study aimed to systematically review the scientific literature to verify the application, efficacy, and safety of TC training programs. METHODS: PubMed, Scopus, and Web of Sciences databases were used for this review, and randomized controlled trials analyzing TC training programs for elderly people were included. Only articles written in English and published in the last decade were considered. RESULTS: 3 articles were included in the qualitative synthesis including 194 elderly people. The sample size ranged from 12 to 117 and the TC training program from 8 to 12 weeks. The TC training programs were applied to elderly people with metabolic diseases and respiratory diseases. TC training program was effective in elderly people with metabolic diseases while the benefits for respiratory diseases have yet to be clarified. CONCLUSION: TC seems to be a safe, effective, and injury-free training method, despite its limited application in elderly population. Future studies should better investigate this training method in elderly people in order to evaluate the effectiveness in a wider range of diseases.

Changes in kynurenine metabolites in the gray and white matter of the dorsolateral prefrontal cortex of individuals affected by schizophrenia.

Alterations in the kynurenine pathway of tryptophan metabolism have been implicated in the pathophysiology of schizophrenia. Here, we performed an in-depth analysis of all metabolites of the kynurenine pathway, i.e., tryptophan (TRY), kynurenic acid (KYNA), L-kynurenine (KYN), 3-hydroxykynurenine (3-HK), anthranylic acid (ANA), 3-hydroxyanthranylic acid (3-HANA), xanthurenic acid (XA) and quinolinic acid (QUINA), in postmortem samples of the dorsolateral prefrontal cortex (DLPFC, Brodmann area 46, 9) of individuals affected by schizophrenia and non-schizophrenic controls. The analysis was carried out in the gray and white matter. Levels of KYN, 3-HK, ANA, and 3-HANA were significantly increased in both the gray and white matter of the DLPFC of individuals affected by schizophrenia, whereas levels of TRY, KYNA, and QUINA were increased exclusively in the white matter and remained unchanged in the gray matter. These increases in kynurenine metabolites did not correlate with age, sex, duration of the disease, and duration and type of antipsychotic medication. These findings suggest that the two major branches of the kynurenine pathway, i.e., the transamination of KYN into KYNA, and hydroxylation of KYN into 3-HK are activated in the white matter of individuals affected by schizophrenia, perhaps as a result of neuroinflammation, and support the evidence that abnormalities of the white matter are consistenly associated with schizophrenia.

A "double-edged" role for type-5 metabotropic glutamate receptors in pain disclosed by light-sensitive drugs.

Knowing the site of drug action is important to optimize effectiveness and address any side effects. We used light-sensitive drugs to identify the brain region-specific role of mGlu5 metabotropic glutamate receptors in the control of pain. Optical activation of systemic JF-NP-26, a caged, normally inactive, negative allosteric modulator (NAM) of mGlu5 receptors, in cingulate, prelimbic and infralimbic cortices and thalamus inhibited neuropathic pain hypersensitivity. Systemic treatment of alloswitch-1, an intrinsically active mGlu5 receptor NAM, caused analgesia, and the effect was reversed by light-induced drug inactivation in in the prelimbic and infralimbic cortices, and thalamus. This demonstrates that mGlu5 receptor blockade in the medial prefrontal cortex and thalamus is both sufficient and necessary for the analgesic activity of mGlu5 receptor antagonists. Surprisingly, when light was delivered in the basolateral amygdala, local activation of systemic JF-NP-26 reduced pain thresholds, whereas inactivation of alloswitch-1 enhanced analgesia. Electrophysiological analysis showed that alloswitch-1 increased excitatory synaptic responses in prelimbic pyramidal neurons evoked by stimulation of BLA input, and decreased feedforward inhibition of amygdala output neurons by BLA. Both effects were reversed by optical silencing and reinstated by optical reactivation of alloswitch-1. These findings demonstrate for the first time that the action of mGlu5 receptors in the pain neuraxis is not homogenous, and suggest that blockade of mGlu5 receptors in the BLA may limit the overall analgesic activity of mGlu5 receptor antagonists. This could explain the suboptimal effect of mGlu5 NAMs on pain in human studies and validate photopharmacology as an important tool to determine ideal target sites for systemic drugs.

Physical Activity in Patients with Neuromuscular Disease Three Years after COVID-19, a Longitudinal Survey: The After-Effects of the Quarantine and the Benefits of a Return to a Healthier Life-Style.

BACKGROUND: Quarantine was one of the strategies adopted by governments against the spread of COVID-19. This restriction has caused an increase in sedentary behaviors and a decrease in the practice of physical activity (PA), with a consequent negative impact on lifestyle both in healthy people and in those who need constant practice of PA to combat diseases, such as patients suffering from neuromuscular diseases (NMDs). Hence, this study aimed to compare PA levels among patients with NMD during and after quarantine. METHODS: An adapted version of the International Physical Activity Questionnaire Short-Form and the Short-Form Health Survey were administered during COVID-19 quarantine (T0) and after 3 years (T1) to 91 Italian patients with NMDs. RESULTS: We found a significant increase in the total PA level at T1, with no significant changes in vigorous-intensity PA. Moreover, a significant decrease in the PA level was found among the patients with different NMDs. No significant changes in physical component scores and mental component scores were detected. CONCLUSIONS: Our results suggest that it would be necessary to provide alternative indoor exercise settings to prevent the adoption of sedentary behaviors.

Sex differences in the determination of prescribed load in ballistic bench press.

Introduction: The objectives of the present study were twofold: first, to identify the specific relative load at which the concentric motion transforms into a purely propulsive action among women, and second, to compare the load-velocity relationships between men and women during the bench press throw. Methods: Fourteen men and fourteen women participated in a test where they progressively increased the load until reaching their one-repetition maximum (1RM) in the bench press exercise. Linear regression models were employed to elucidate the relationships between load and velocity, as well as load and the propulsive phase (% of total concentric time). Additionally, ANCOVA was utilized to compare the linear regression models between men and women. Results: The results revealed strong and linear associations between load and mean propulsive velocity (MPV) for both men and women, as well as between load and the propulsive phase. Notably, there were significant differences in MPV and the propulsive phase concerning load between men and women. Women transitioned into a fully propulsive concentric phase at approximately 80% of their 1RM, while men achieved this entirely propulsive phase at around 85% of their 1RM. Furthermore, women exhibited reduced velocities when handling lighter relative loads compared to men. Conversely, women demonstrated higher velocities when dealing with loads exceeding 85% of their 1RM in contrast to their male counterparts. Discussion: These findings hold notable implications for prescribing bench press throw loads for women, which should differ from those recommended for men. Further studies are necessary to validate the efficacy of the proposed load recommendations.

Up-regulation of the Trace Amine Receptor, TAAR-1, in the Prefrontal Cortex of Individuals Affected by Schizophrenia.

BACKGROUND AND HYPOTHESIS: Type-1 trace amine-associated receptors (TAAR1) modulate dopaminergic and glutamatergic neurotransmission and are targeted by novel antipsychotic drugs. We hypothesized that schizophrenia (SCZ) causes adaptive changes in TAAR1 expression in the prefrontal cortex. STUDY DESIGN: We measured TAAR1 mRNA and protein levels by quantitative PCR and immunoblotting in post-mortem prefrontal cortical samples obtained from 23 individuals affected by SCZ and 23 non-schizophrenic controls (CTRL). Data were correlated with a number of variables in both groups. STUDY RESULTS: TAAR1 mRNA levels were largely increased in the SCZ prefrontal cortex, and did not correlate with age, age at onset and duration of SCZ, or duration of antipsychotic treatment. For the analysis of TAAR1 protein levels, CTRL and SCZ were divided into 2 subgroups, distinguished by the extent of neuropathological burden. CTRL with low neuropathological burden (LNB) had lower TAAR1 protein levels than CTRL with high neuropathological burden (HNB), whereas no changes were found between LNB and HNB in the SCZ group. TAAR1 protein levels were lower in CTRL with LNB with respect to all SCZ samples or to SCZ samples with LNB. In the SCZ group, levels showed an inverse correlation with the duration of antipsychotic treatment and were higher in individuals treated with second-generation antipsychotics as compared with those treated with first-generation antipsychotics. CONCLUSIONS: The up-regulation of TAAR1 observed in the SCZ prefrontal cortex supports the development of TAAR1 agonists as new promising drugs in the treatment of SCZ.

Identifying molecular tags selectively retained on the surface of brain endothelial cells to generate artificial targets for therapy delivery.

Current strategies to identify ligands for brain delivery select candidates based on preferential binding to cell-membrane components (CMC) on brain endothelial cells (EC). However, such strategies generate ligands with inherent brain specificity limitations, as the CMC (e.g., the transferrin receptor TfR1) are also significantly expressed on peripheral EC. Therefore, novel strategies are required to identify molecules allowing increased specificity of therapy brain delivery. Here, we demonstrate that, while individual CMC are shared between brain EC and peripheral EC, their endocytic internalization rate is markedly different. Such differential endocytic rate may be harnessed to identify molecular tags for brain targeting based on their selective retention on the surface of brain EC, thereby generating 'artificial' targets specifically on the brain vasculature. By quantifying the retention of labelled proteins on the cell membrane, we measured the general endocytic rate of primary brain EC to be less than half that of primary peripheral (liver and lung) EC. In addition, through bio-panning of phage-displayed peptide libraries, we unbiasedly probed the endocytic rate of individual CMC of liver, lung and brain endothelial cells. We identified phage-displayed peptides which bind to CMC common to all three endothelia phenotypes, but which are preferentially endocytosed into peripheral EC, resulting in selective retention on the surface of brain EC. Furthermore, we demonstrate that the synthesized free-form peptides are capable of generating artificial cell-surface targets for the intracellular delivery of model proteins into brain EC with increasing specificity over time. The developed identification paradigm, therefore, demonstrates that the lower endocytic rate of individual CMC on brain EC can be harnessed to identify peptides capable of generating 'artificial' targets for the selective delivery of proteins into the brain vasculature. In addition, our approach identifies brain-targeting peptides which would have been overlooked by conventional identification strategies, thereby increasing the repertoire of candidates to achieve specific therapy brain delivery.

Relationship between external and internal load indicators and injury using machine learning in professional soccer: a systematic review and meta-analysis.

This study verified the relationship between internal load (IL) and external load (EL) and their association on injury risk (IR) prediction considering machine learning (ML) approaches. Studies were included if: (1) participants were male professional soccer players; (2) carried out for at least 2 sessions, exercises, or competitions; (3) correlated training load (TL) with non-contact injuries; (4) applied ML approaches to predict TL and non-contact injuries. TL included: IL indicators (Rating of Perceived Exertion, RPE; Session-RPE, Heart Rate, HR) and EL indicators (Global Positioning System, GPS variables); the relationship between EL and IL through index, ratio, formula; ML indicators included performance measures, predictive performance of ML methods, measure of feature importance, relevant predictors, outcome variable, predictor variable, data pre-processing, features selection, ML methods. Twenty-five studies were included. Eleven addressed the relationship between EL and IL. Five used EL/IL indexes. Five studies predicted IL indicators. Three studies investigated the association between EL and IL with IR. One study predicted IR using ML. Significant positive correlations were found between S-RPE and total distance (TD) (r = 0.73; 95% CI (0.64 to 0.82)) as well as between S-RPE and player load (PL) (r = 0.76; 95% CI (0.68 to 0.84)). Association between IL and EL and their relationship with injuries were found. RPE, S-RPE, and HR were associated with different EL indicators. A positive relationship between EL and IL indicators and IR was also observed. Moreover, new indexes or ratios (integrating EL and IL) to improve knowledge regarding TL and fitness status were also applied. ML can predict IL indicators (HR and RPE), and IR. The present systematic review was registered in PROSPERO (CRD42021245312).

Psychological Antecedents of Italian Sport Coaches' Coaching Behaviors: The Role of Basic Psychological Needs, Motivation and Subjective Vitality.

The extant literature has identified some variables that are associated with sport coaches' coaching style, like their basic psychological need satisfaction, their motivation for coaching, and their psychological well-being. Framed from a conceptual framework based on Self-Determination Theory applied to sport coaches, the current study explored how sport coaches' basic psychological needs are associated with their motivation (intrinsic vs. external), subjective vitality, and coaching behaviors (autonomy-supporting vs. need-thwarting). Participants were 184 Italian sport coaches (males = 65%, Mage = 40.22, SD = 11.55, age range 19-74 years) from the "Centro CONI" project. They were requested to fill out online self-report questionnaires assessing the study variables. Structural equation modeling analyses suggested that sport coaches' satisfaction of basic psychological needs was associated with higher levels of intrinsic motivation to train as well as with higher levels of vitality that, in turn, were associated with coaching behaviors supporting athletes' autonomy. Moreover, sport coaches' frustration of basic psychological needs was associated with higher levels of external motivation to train that, in turn, were associated with higher levels of a need-thwarting coaching style. Overall, the findings provided additional support for understanding how sport coaches' basic psychological needs relate to their coaching styles.

The Role of Operating Conditions in the Precipitation of Magnesium Hydroxide Hexagonal Platelets Using NaOH Solutions.

Magnesium hydroxide, Mg(OH)2, is an inorganic compound extensively employed in several industrial sectors. Nowadays, it is mostly produced from magnesium-rich minerals. Nevertheless, magnesium-rich solutions, such as natural and industrial brines, could prove to be a great treasure. In this work, synthetic magnesium chloride and sodium hydroxide (NaOH) solutions were used to recover Mg(OH)2 by reactive crystallization. A detailed experimental campaign was conducted aiming at producing grown Mg(OH)2 hexagonal platelets. Experiments were carried out in a stirred tank crystallizer operated in single- and double-feed configurations. In the single-feed configuration, globular and nanoflakes primary particles were obtained, as always reported in the literature when NaOH is used as a precipitant. However, these products are not complying with flame-retardant applications that require large hexagonal Mg(OH)2 platelets. This work suggests an effective precipitation strategy to favor crystal growth while, at the same time, limiting the nucleation mechanism. The double-feed configuration allowed the synthesis of grown Mg(OH)2 hexagonal platelets. The influence of reactant flow rates, reactant concentrations, and reaction temperature was analyzed. Scanning electron microscopy (SEM) pictures were also taken to investigate the morphology of Mg(OH)2 crystals. The proposed precipitation strategy paves the road to satisfy flame-retardant market requirements.

Role of the Lactide:Glycolide Ratio in PLGA Nanoparticle Stability and Release under Lysosomal Conditions for Enzyme Replacement Therapy of Lysosomal Storage Disorders.

Prior studies demonstrated that encapsulation in poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) enhanced the delivery of enzymes used for replacement therapy (ERT) of lysosomal storage disorders (LSDs). This study examined how the copolymer lactide:glycolide ratio impacts encapsulation, physicochemical characteristics, stability, and release under lysosomal conditions. Hyaluronidase, deficient in mucopolysaccharidosis IX, was encapsulated in NPs synthesized using 50:50, 60:40, or 75:25 lactide:glycolide copolymers. All NPs had diameters compatible with cellular transport (≤168 nm) and polydispersity indexes (≤0.16) and ζ-potentials (≤-35 mV) compatible with colloidal stability. Yet, their encapsulation efficiency varied, with 75:25 NPs and 60:40 NPs having the lowest and highest EE, respectively (15% vs. 28%). Under lysosomal conditions, the 50:50 copolymer degraded fastest (41% in 1 week), as expected, and the presence of a targeting antibody coat did not alter this result. Additionally, 60:40 NPs destabilized fastest (<1 week) because of their smaller diameter, and 75:25 NPs did not destabilize in 4 weeks. All formulations presented burst release under lysosomal conditions (56-78% of the original load within 30 min), with 50:50 and 60:40 NPs releasing an additional small fraction after week 1. This provided 4 weeks of sustained catalytic activity, sufficient to fully degrade a substrate. Altogether, the 60:40 NP formulation is preferred given its higher EE, and 50:50 NPs represent a valid alternative, while the highest stability of 75:25 NPs may impair lysosomes. These results can guide future studies aiming to translate PLGA NP-based ERT for this and other LSDs.

Toward a New Conceptual Approach to "Intensity" in Soccer Player's Monitoring: A Narrative Review.

ABSTRACT: Pillitteri, G, Clemente, FM, Petrucci, M, Rossi, A, Bellafiore, M, Bianco, A, Palma, A, and Battaglia, G. Toward a new conceptual approach to "intensity" in soccer player's monitoring: A narrative review. J Strength Cond Res 37(9): 1896-1911, 2023-In the last decade, monitoring physiological and match-related demands in soccer has become an increasingly common practice in sports sciences. One of the great challenges during monitoring process is the identification of key indicators that permit to generalize evidence and sustain decision-making process during training prescription. Actually, one of the major debates in the scientific community and among practitioners is the identification of the "intensity" concept. Defining a given training session or exercise based on "intensity" is difficult due to the fact that a huge amount of indicators are available (related both to the performed activities and to the athletes' psychophysiological responses). These indicators can lead to specific outcomes with different interpretations. The current narrative review aims to discuss the different measures approaches used in soccer to describe the intensity for both internal and external demands. In addition, a second purpose of this review is to propose general recommendations for combining intensity indicators with the aim of defining an overall intensity score of a training session or drill.