Mass Spectral Analysis of Protein-based Radicals Using DBNBS: Nonradical adduct formation versus spin trapping

Protein-based radicals generated in the reaction of ferricytochrome c (cyt c) with H2O2 were investigated by electrospray mass spectrometry (ESI-MS) using 3,5-dibromo-4-nitrosobenzenesulfonate (DBNBS). Up to four DBNBS-cyt c adducts were observed in the mass spectra. However, by varying the reaction conditions (0–5 molar equivalents of H2O2 and substituting cytc with its cyanide adduct which is resistant to peroxidation), noncovalent DBNBS adduct formation was inferred. Nonetheless, optical difference spectra revealed the presence of a small fraction of covalently trapped DBNBS. To probe the nature of the noncovalent DBNBS adducts, the less basic proteins, metmyoglobin (Mb) and α-lactalbumin, were substituted for cyt c in the cytc/H2O2/DBNBS reaction. A maximum of two DBNBS adducts were observed in the mass spectra of the products of the Mb/H2O2/DBNBS reactions, whereas no adducts were detected following α-lactalbumin/H2O2/DBNBS incubation, which is consistent with adduct formation via spin trapping only. Titration with DBNBS at pH 2.0 yielded noncovalent DBNBS-cyt c adducts and induced folding of acid-denatured cyt c, as monitored by ESI-MS and optical spectroscopy, respectively. Thus, the noncovalent DBNBS-cyt c mass adducts observed are assigned to ion pair formation occurring between the negatively charged sulfonate group on DBNBS and positively charged surface residues on cyt c. The results reveal the pitfalls inherent in using mass spectral data with negatively charged spin traps such as DBNBS to identify sites of radical formation on basic proteins such as cyt c

Perception of Time-Discrete Haptic Feedback on the Waist is Invariant with Gait Events

The effectiveness of haptic feedback devices highly depends on the perception of tactile stimuli, which differs across body parts and can be affected by movement. In this study, a novel wearable sensory feedback apparatus made of a pair of pressure-sensitive insoles and a belt equipped with vibrotactile units is presented; the device provides time-discrete vibrations around the waist, synchronized with biomechanically-relevant gait events during walking. Experiments with fifteen healthy volunteers were carried out to investigate users' tactile perception on the waist. Stimuli of different intensities were provided at twelve locations, each time synchronously with one pre-defined gait event (i.e. heel strike, flat foot or toe off), following a pseudo-random stimulation sequence. Reaction time, detection rate and localization accuracy were analyzed as functions of the stimulation level and site and the effect of gait events on perception was investigated. Results revealed that above-threshold stimuli (i.e. vibrations characterized by acceleration amplitudes of 1.92g and 2.13g and frequencies of 100 Hz and 150 Hz, respectively) can be effectively perceived in all the sites and successfully localized when the intertactor spacing is set to 10 cm. Moreover, it was found that perception of time-discrete vibrations was not affected by phase-related gating mechanisms, suggesting that the waist could be considered as a preferred body region for delivering haptic feedback during walking

Combining Varenicline (Chantix) with Naltrexone Decreases Alcohol Drinking More Effectively Than Does Either Drug Alone in a Rodent Model of Alcoholism

Background This study examined whether varenicline (VAR), or naltrexone (NTX), alone or in combination, reduces alcohol drinking in alcohol-preferring (P) rats with a genetic predisposition toward high voluntary alcohol intake. Methods Alcohol-experienced P rats that had been drinking alcohol (15% v/v) for 2 h/d for 4 weeks were fed either vehicle (VEH), VAR alone (0.5, 1.0, or 2.0 mg/kg body weight [BW]), NTX alone (10.0, 15.0, or 20.0 mg/kg BW), or VAR + NTX in 1 of 4 dose combinations (0.5 VAR + 10.0 NTX, 0.5 VAR + 15.0 NTX, 1.0 VAR + 10.0 NTX, or 1.0 VAR + 15.0 NTX) at 1 hour prior to alcohol access for 10 consecutive days, and the effects on alcohol intake were assessed. Results When administered alone, VAR in doses of 0.5 or 1.0 mg/kg BW did not alter alcohol intake but a dose of 2.0 mg/kg BW decreased alcohol intake. This effect disappeared when drug treatment was terminated. NTX in doses of 10.0 and 15.0 mg/kg BW did not alter alcohol intake but a dose of 20.0 mg/kg BW decreased alcohol intake. Combining low doses of VAR and NTX into a single medication reduced alcohol intake as well as did high doses of each drug alone. Reduced alcohol intake occurred immediately after onset of treatment with the combined medication and continued throughout prolonged treatment. Conclusions Low doses of VAR and NTX, when combined in a single medication, reduce alcohol intake in a rodent model of alcoholism. This approach has the advantage of reducing potential side effects associated with each drug. Lowering the dose of NTX and VAR in a combined treatment approach that maintains efficacy while reducing the incidence of negative side effects may increase patient compliance and improve clinical outcomes for alcoholics and heavy drinkers who want to reduce their alcohol intake

Using pERK immunostaining to quantify neuronal activity induced by stress in zebrafish larvae

The larval zebrafish has emerged as a very useful model organism to study the neuronal circuits controlling neuroendocrine and behavioral responses to stress. This protocol describes how to expose zebrafish larvae to hyperosmotic stress and test whether candidate populations of neurons are activated or inhibited by the stressor using a relatively rapid immunofluorescence staining approach. This approach takes advantage of the phosphorylation of the extracellular signal-regulated kinase (ERK) upon neuronal activation. For complete details on the use and execution of this protocol, please refer to Corradi et al. (2022)

The Relationship between Psychological Distress during the Second Wave Lockdown of COVID-19 and Emotional Eating in Italian Young Adults: The Mediating Role of Emotional Dysregulation

This cross-sectional study aims to investigate the impact of psychological distress experienced during the second wave of the COVID-19 pandemic on emotional eating and to assess the mediating role of emotional dysregulation in a sample of Italian young adults (20-35). A total of 437 participants provided demographical data and were assessed using the Depression Anxiety Stress Scale, the Difficulties in Emotion Regulation Scale, and the Emotional Eating subscale of the Dutch Eating Behavior Questionnaire. Correlational analyses were performed to assess the relationship between continuous variables, while ANOVA was conducted to detect differences between males and females for emotional eating. To assess whether demographic and clinical data predicted emotional eating, hierarchical linear regression was performed. Then, a mediation analysis was conducted to assess whether emotional dysregulation was a mediator between psychological distress and emotional eating. Emotional eating was associated with psychological distress and emotional dysregulation. Moreover, higher levels of emotional eating were found in females than in males. Predictors of emotional eating were sex, psychological distress, and emotional dysregulation. Mediation analyses showed that the indirect effect of psychological distress on emotional eating through emotional dysregulation was significant (b = 0.0069; SE = 0.0024; CI = 0.0024-0.0118), confirming that the relationship between psychological distress and emotional eating was mediated by emotional dysregulation, controlling for sex. The model explained 26.8% (R-2 = 0.2680) of the variance. These findings may help to plan and develop psychological interventions aimed at addressing emotional eating in young adults by targeting emotional dysregulation

Design, synthesis and biological evaluation of novel bicyclo[1.1.1]pentane-basedx-acidic amino acids as glutamate receptors ligands

A novel series of bicyclo[1.1.1]pentane-based x-acidic amino acids, including (2S)- and (2R)-3-(30-carboxybicyclo[ 1.1.1]pentyl)alanines (8 and 9), (2S)- and (2R)-2-(30-carboxymethylbicyclo[1.1.1]pentyl)glycines (10 and 11), and (2S)- and (2R)-3-(30-phosphonomethylbicyclo[1.1.1]pentyl)glycines (12 and 13), were synthesized and evaluated as glutamate receptor ligands. Among them, (2R)-3-(30-phosphonomethylbicyclo[ 1.1.1]pentyl)glycine (13) showed relatively high affinity and selectivity at the NMDA receptor. The results are also discussed in light of pharmacophoric modelling studies of NMDA agonists and antagonists

Luspatercept improves hemoglobin levels and blood transfusion requirements in a study of patients with b-thalassemia

b-thalassemia is a hereditary disorder with limited approved treatment options; patients experience anemia and its complications, including iron overload. The study aim was to determine whether luspatercept could improve anemia and disease complications in patients with b-thalassemia. This open-label, nonrandomized, uncontrolled study consisted of a 24-week dose-finding and expansion stage (initial stage) and a 5-year extension stage, currently ongoing. Sixty-four patients were enrolled; 33 were non\u2013transfusion dependent (mean hemoglobin, <10.0 g/dL; <4 red blood cell [RBC] units transfused per 8 weeks), and 31 were transfusion dependent (\u20214 RBC units per 8 weeks). Patients received 0.2 to 1.25 mg/kg luspatercept subcutaneously every 21 days for \u20215 cycles (dose-finding stage) and 0.8 to 1.25 mg/kg (expansion cohort and 5-year extension). The primary end point was erythroid response, defined as hemoglobin increase of \u20211.5 g/dL from baseline for \u202114 consecutive days (without RBC transfusions) for non\u2013transfusion-dependent patients or RBC transfusion burden reduction \u202120% over a 12-week period vs the 12 weeks before treatment for transfusion-dependent patients. Eighteen non\u2013transfusion-dependent patients (58%) receiving higher dose levels of luspatercept (0.6-1.25 mg/kg) achieved mean hemoglobin increase \u20211.5 g/dL over \u202114 days vs baseline. Twenty-six (81%) transfusion-dependent patients achieved \u202120% reduction in RBC transfusion burden. The most common grade 1 to 2 adverse events were bone pain, headache, and myalgia. As of the cutoff, 33 patients remain on study. In this study, a high percentage of b-thalassemia patients receiving luspatercept had hemoglobin or transfusion burden improvements. These findings support a randomized clinical trial to assess efficacy and safety. This study was registered at www.clinicaltrials.gov as #NCT01749540 and #NCT02268409

Long-term treatment with deferiprone enhances left ventricular ejection function when compared to deferoxamine in patients with thalassemia major

Transfusion and iron chelation treatment have significantly reduced morbidity and improved survival of patients with thalassemia major. However, cardiac disease continues to be the most common cause of death. We report the left-ventricular ejection fraction, determined by echocardiography, in one hundred sixtyeight patients with thalassemia major followed for at least 5 years who received continuous monotherapy with deferoxamine (N = 108) or deferiprone (N = 60). The statistical analysis, using the generalized estimating equations model, indicated that the group treated with deferiprone had a significantly better left-ventricular ejection fraction than did those treated with deferoxamine (coefficient 0.97; 95% CI 0.37; 1.6, p = 0.002). The heart may be particularly sensitive to iron-induced mitochondrial damage because of the large number of mitochondria and its low level of antioxidants. Deferiprone, because of its lower molecular weight, might cross into heart mitochondria more efficiently, improving their activity and, thereby, myocardial cell function. Our findings indicate that the long-term administration of deferiprone significantly enhances left-ventricular function over time in comparison with deferoxamine treatment. However, because of limitations related to the design of this study, these findings should be confirmed in a prospective, randomized clinical trial

Cutaneous Involvement in Diseases with Plasma Cell Differentiation: Diagnostic Approach

Neoplasms with plasma cell differentiation may occasionally involve the skin. Cutaneous lesions may represent the first sign of an underlying systemic plasma cell malignancy, such as multiple myeloma, or the skin itself may be the primary site of occurrence of a hematological tumor with plasma cell differentiation. Starting from examples encountered in our daily practice, we discussed the diagnostic approach pathologists and clinicians should use when faced with cutaneous lesions with plasma cell differentiation. Cases of primary cutaneous marginal zone lymphoma, localized primary amyloidosis/amyloidoma, and cutaneous manifestations (secondary either to multiple myeloma or to plasmablastic lymphoma) are discussed, focusing on the importance of the adequate patient’s work-up and precise clinicopathological correlation to get to the correct diagnosis and appropriate treatment. The pertinent literature has been reviewed, and the clinical presentation, pathological findings, main differential diagnoses, treatment, and outcome of neoplasms with plasma cell differentiation involving the skin are discussed