Insights on Stability Constants and Structures of Complexes between Coumarin Derivatives and Pb(II) in Aqueous Media.

In the frame of a systematic study on the sequestering ability of natural antioxidants towards metal cations, here the complexation of coumarin-3-carboxilic acid (HCCA) with Pb(II) and the overall stability constants of the resulting complexes, at 37 °C and in 0.16 M NaClO4, are discussed. Reaction of Pb(ClO4)2 with HCCA in an aqueous medium at a pH range from 2 to 6 and various ratios (1:1-1:10) yielded the Pb-CCA complexes, which were characterized spectrometrically by laser desorption ionization mass spectrometry (LD-MS). LD-MS has provided the composition and structure of Pb-CCA species according to the speciation model proposed on the basis of the potentiometric data. The graphic representation of the complex's concentration curves is given by the distribution diagram, which provides a whole depiction of the species present in the solution at the selected pH ranges.

The Long-Term Immunogenicity of mRNABNT162b Third Vaccine Dose in Solid Organ Transplant Recipients.

We investigated humoral and T-cell response to a SARS-CoV-2 mRNA vaccine in solid organ transplant recipients (SOT-Rs) and healthy donors (HDs) before (T0) and after two (T1) and twelve months (T2) since the third dose administration. SOT-Rs were stratified according to the transplanted organ and to the time elapsed since the transplant. In SOT-Rs, detectable levels of anti-S antibodies were observed in 44%, 81% and 88% at T0, T1 and T2, respectively. Conversely, anti-S antibody levels were detected in 100% of HD at all time points. Lower antibody titers were observed in SOT-Rs compared to HDs, even stratifying by transplanted organs and the time elapsed since transplant. Lower percentages of responding and polyfunctional T-cells were observed in SOT-Rs as well as in each subgroup of SOT-Rs compared to HDs. At both T0 and T1, in SOT-Rs, a predominance of one cytokine production shortly was observed. Conversely, at T2, a dynamic change in the T-cells subset distribution was observed, similar to what was observed in HDs. In SOT-Rs, the third dose increased the rate of seroconversion, although anti-S levels remained lower compared to HDs, and a qualitatively inferior T-cell response to vaccination was observed. Vaccine effectiveness in SOT-Rs is still suboptimal and might be improved by booster doses and prophylactic strategies.

Molecular monitoring of viral infections in immunocompromised patients in a large university hospital in Italy: reflections after thirteen years of real-life activity.

PURPOSE: This study aimed to investigate the prevalence and viral reactivations of clinical interest in the immunocompromised patient with particular focus on hematologic and solid organ transplant recipients. METHODS: Molecular screening data of CMV, EBV, JCV and BKV from 2011 to 2023 were analyzed. This extensive time span allowed the access to more than 100,000 samples from over 20,000 patients treated at Policlinico Umberto I. It was possible to temporally investigate patient attendance patterns, average age distribution, seasonality of infections, and positivity rates of the analyzed viruses. RESULTS: Between 2019 and 2022 a significant reduction in organ transplants performed and in the positive molecular detection of EBV, JCV and BKV was observed. Additionally, there has been a noteworthy decrease in CMV reactivations, with a reduction of up to 50% starting in 2019. A remarkable reduction of 39% in the rate of CMV viral reactivation has been also achieved in SOT between 2016 and 2023. CONCLUSION: The years following 2019 were profoundly impacted by the COVID-19 pandemic era. This period resulted in a substantial reduction in healthcare services and hospital visits. Furthermore, the introduction of the drug Letermovir in Italy in 2019 demonstrated remarkable efficacy, evidenced by a reduction in CMV reactivations. Additionally, the adoption of a novel clinical approach centered on personalized therapy facilitated improved management of immunocompromised patients.

SARS-CoV-2 pre-exposure prophylaxis with tixagevimab/cilgavimab (AZD7442) provides protection in inborn errors of immunity with antibody defects: a real-world experience.

Background: Preventive strategies against severe COVID-19 in Inborn Errors of Immunity (IEI) include bivalent vaccines, treatment with SARS-CoV-2 monoclonal antibodies (mAbs), early antiviral therapies, and pre-exposure prophylaxis (PrEP). Objective: To assess the effectiveness of the PrEP with tixagevimab/cilgavimab (AZD7442) in IEI with primary antibody defects during the COVID-19 Omicron wave. Methods: A six-month prospective study evaluated the SARS-CoV-2 infection rate and the COVID-19 severity in the AZD7442 group, in the no-AZD7442 group, and in a group of patients with a recent SARS-CoV-2 infection (< three months). Spike-specific IgG levels were measured at regular intervals. Results: Six out of thirty-three patients (18%) and 54/170 patients (32%) became infected in the AZD7442 group and in the no-AZD7442 group, respectively. Within 90 days post-administration, the AZD7442 group was 85% less likely to be infected and 82% less likely to have a symptomatic disease than the no-AZD7442 group. This effect was lost thereafter. In the entire cohort, no mortality/hospitalisation was observed. The control group of 35 recently infected patients was 88% and 92% less likely to be infected than the AZD7442 and no-AZD7442 groups. Serum anti-Spike IgG reached the highest peak seven days post-AZD7442 PrEP then decreased, remaining over 1000 BAU/mL 180 days thereafter. Conclusion: In patients with IEI and antibody defects, AZD7442 prophylaxis had a transient protective effect, possibly lost possibly because of the appearance of new variants. However, PrEP with newer mAbs might still represent a feasible preventive strategy in the future in this population.

Differential expression of Type I interferon and inflammatory genes in SARS-CoV-2-infected patients treated with monoclonal antibodies.

INTRODUCTION: Considering the reported efficacy of monoclonal antibodies (mAbs) directed against the Spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in reducing disease severity, the aim of this study was to investigate the innate immune response before and after mAbs treatment in 72 vaccinated and 31 unvaccinated SARS-CoV-2 patients. METHODS: The mRNA levels of IFN-I, IFN-related genes and cytokines were evaluated using RT/real-time quantitative PCR. RESULTS: Vaccinated patients showed increased rate of negative SARS-CoV-2 PCR tests on nasopharyngeal swab compared with unvaccinated ones after mAbs treatment (p = .002). Unvaccinated patients had lower IFN-α/ω and higher IFN-related genes (IFNAR1, IFNAR2, IRF9, ISG15, ISG56 and IFI27) and cytokines (IL-6, IL-10 and TGF-ß) mRNA levels compared to vaccinated individuals before mAbs (p < .05 for all genes). Increased IFN-α/ω, IFNAR1, IFNAR2 and IRF9 levels were observed in unvaccinated patients after mAbs treatment, while the mRNA expression ISGs and IL-10 were reduced in all patients. CONCLUSION: These data suggest that anti-S vaccinated patients have increased levels of innate immune genes compared to unvaccinated ones. Also, gene expression changes in IFN genes after mAbs administration are different according to the vaccination status of patients.

Adherence to SARS-CoV-2 Vaccination Recommendations among Patients with Substance Use Disorders: A Cross-Sectional Study in Rome, Italy.

Adherence to vaccination recommendations is a challenge for national immunization programs. We quantified adherence to COVID-19 vaccination recommendations in people with substance use disorders (SUDs) attending an outpatient addiction center in Rome, Italy; we investigated the determinants of adherence, and also analyzed patient risk perception and compliance with preventive measures. A multivariable logistic regression model identified predictors of adherence to vaccination recommendations, with statistical validity tested by estimating adjusted odds ratios (aORs) and 95% confidence intervals (CIs). From December 2021 to January 2022, 200 SUD patients completed a questionnaire, 80% of whom reported being vaccinated against SARS-CoV-2 (minimum one dose). Negative predictors of vaccine uptake included being non-Italian (aOR: 0.36, 95% CI: 0.13-0.97), having coexisting comorbidities (aOR: 0.35, 95% CI: 0.13-0.95), and previous use of heroin (aOR: 0.24, 95% CI: 0.08-0.71). No difference was found for cocaine use, demographic characteristics, previous COVID-19 infection, methadone therapy, or compliance with preventive measures. Major reasons for non-adherence to vaccination recommendations were fear of side effects, insufficient recognition of the importance of vaccination, bureaucratic issues, and lack of trust in the authorities. Given their vulnerability, additional efforts are needed to facilitate access to vaccination for people with SUDs, and to limit disinformation around vaccines..

Aqueous chemistry of nalidixic acid and its complexes with biological relevant cations: A combination of potentiometric, UV spectrophotometric, MS and MS/MS study.

Nalidixic acid (NAL) is a broad-spectrum antimicrobial widely used for urinary tract infections. As demonstrated, complexation of NAL with Zn2+, Mn2+ and Cu2+ was often used to get new formulations with an enhanced efficiency and potency. Therefore, the elucidation of behavior of NAL in solution and of its interaction with metal cations are crucial to better understand the influence of complexation on NAL efficiency and to find the optimal conditions to propose novel formulations. As a preliminary study, spectrophotometric titrations were carried out on NAL to determine the values of the protonation constants and to define its acid-base behavior. Then, the interaction with the three metal cations Zn2+, Mn2+ and Cu2+ was investigated by potentiometric and spectrophotometric titrations, varying the conditions of temperature, ionic strength and metal-ligand ratio, thus allowing to get the most robust speciation model and to determine the formation constants with Zn2+, Mn2+, and Cu2+ under different conditions, the sequestering ability of NAL towards metal cations, the formation enthalpic and entropic changes. A simulation under serum conditions was reported to show the relevance of the investigated species. Finally, LD-MS (laser desorption ionization mass spectrometry) and MS/MS analyses highlighted for all systems the formation of the complex species between Zn2+, Mn2+ and Cu2+ with NAL. MS/MS investigations assigned the sites of coordination of the ligand with the metal cation. More precisely, deprotonated NAL coordinates the metal cation via the oxygens of the carboxylate and the carbonyl groups.

Evaluation of the Factors Associated with Reinfections towards SARS-CoV-2 Using a Case Control Design.

OBJECTIVE: The risk of reinfection with SARS-CoV-2 has been rapidly increased with the circulation of concerns about variants. So, the aim of our study was to evaluate the factors that increase the risk of this reinfection in healthcare workers compared to those who have never been positive and those who have had only one positivity. METHODS: A case-control study was carried out at the Teaching Hospital Policlinico Umberto I in Rome, Sapienza University of Rome, in the period between 6 March 2020 and 3 June 2022. Cases are healthcare workers who have developed a reinfection with the SARS-CoV-2 virus, while controls were either healthcare workers who tested positive once or those who have never tested positive for SARS-CoV-2. RESULTS: 134 cases and 267 controls were recruited. Female gender is associated with a higher odds of developing reinfection (OR: 2.42; 95% CI: 1.38-4.25). Moreover, moderate or high alcohol consumption is associated with higher odds of reinfection (OR: 1.49; 95% CI: 1.19-1.87). Diabetes is also associated with higher odds of reinfection (OR: 3.45; 95% CI: 1.41-8.46). Finally, subjects with increased red blood cell counts have higher odds of reinfection (OR: 1.69; 95% CI: 1.21-2.25). CONCLUSION: From the prevention point of view, these findings indicate that particular attention should be paid to subjects with diabetes mellitus, women and alcoholic drinkers. These results could also suggest that contact tracing represents a fundamental approach model against the SARS-CoV-2 pandemic, together with the health information of participants.

Anti-N SARS-CoV-2 assays for evaluation of natural viral infection.

BACKGROUND: The 2019 coronavirus (COVID-19) epidemic, required the development of different diagnostic tests. While reverse transcriptase real-time PCR (RT-PCR) remains the first-line test of choice in acute infection diagnosis, anti-N antibodies serological assays provide a valuable tool to differentiate natural SARS-CoV-2 immunological response from that induced by vaccination, thus the goal of our study was to evaluate three serological tests agreement for these antibodies detection. METHODS: Three anti-N different tests were examined in 74 sera from patients referred or not COVID infection: immunochromatographic rapid test (Panbio™ COVID-19 IgG/IgM Rapid Test Device Abbott, Germany), ELISA kit (NovaLisa® SARS-CoV-2 IgG and IgM NovaTech Immunodiagnostic GmbH, Germany) and ECLIA immunoassay (Elecsys® Anti-SARS-CoV-2 Roche Diagnostics, Manheim, Germany). RESULTS: Qualitative comparison of the three analytical methods revealed a moderate agreement between ECLIA immunoassay and immunochromatographic rapid test (Cohen kappa coefficient κ = 0.564). Correlation analysis indicated weak positive correlation between total Ig (IgT) detected by ECLIA immunoassay and IgG by ELISA test (p < 0.0001), the analysis of ECLIA IgT and IgM ELISA detected, showed no statistical correlation. CONCLUSION: Comparison between of three analytical systems available for anti-N SARS-CoV-2 IgG and IgM antibodies showed a general agreement when compared to detect total and G class immunoglobulins, while doubtful or discordant results have been highlighted for IgT and IgM class. Anyway, all the tests examined provide reliable results to assess the serological status of SARS-CoV-2 infected patients.

A Picrocrocin-Enriched Fraction from a Saffron Extract Affects Lipid Homeostasis in HepG2 Cells through a Non-Statin-like Mode.

Dyslipidemia is a lipid metabolism disorder associated with the loss of the physiological homeostasis that ensures safe levels of lipids in the organism. This metabolic disorder can trigger pathological conditions such as atherosclerosis and cardiovascular diseases. In this regard, statins currently represent the main pharmacological therapy, but their contraindications and side effects limit their use. This is stimulating the search for new therapeutic strategies. In this work, we investigated in HepG2 cells the hypolipidemic potential of a picrocrocin-enriched fraction, analyzed by high-resolution 1H NMR and obtained from a saffron extract, the stigmas of Crocus sativus L., a precious spice that has already displayed interesting biological properties. Spectrophotometric assays, as well as expression level of the main enzymes involved in lipid metabolism, have highlighted the interesting hypolipidemic effects of this natural compound; they seem to be exerted through a non-statin-like mechanism. Overall, this work provides new insights into the metabolic effects of picrocrocin, thus confirming the biological potential of saffron and paving the way for in vivo studies that could validate this spice or its phytocomplexes as useful adjuvants in balancing blood lipid homeostasis.

Torque teno virus (TTV): A gentle spy virus of immune status, predictive marker of seroconversion to COVID-19 vaccine in kidney and lung transplant recipients.

To date, no comprehensive marker to monitor the immune status of patients is available. Given that Torque teno virus (TTV), a known human virome component, has previously been identified as a marker of immunocompetence, it was retrospectively investigated whether TTV viral load may also represent a marker of ability to develop antibody in response to COVID-19-BNT162B2 vaccine in solid organ transplant recipients (SOT). Specifically, 273 samples from 146 kidney and 26 lung transplant recipients after successive doses of vaccine were analyzed. An inverse correlation was observed within the TTV copy number and anti-Spike IgG antibody titer with a progressive decrease in viremia the further away from the transplant date. Analyzing the data obtained after the second dose, a significant difference in TTV copy number between responsive and nonresponsive patients was observed, considering a 5 log10 TTV copies/mL threshold to discriminate between the two groups. Moreover, for 86 patients followed in their response to the second and third vaccination doses a 6 log10 TTV copies/mL threshold was used to predict responsivity to the booster dose. Although further investigation is necessary, possibly extending the analysis to other patient categories, this study suggests that TTV can be used as a good marker of vaccine response in transplant patients.

Edible Insects an Alternative Nutritional Source of Bioactive Compounds: A Review.

Edible insects have the potential to become one of the major future foods. In fact, they can be considered cheap, highly nutritious, and healthy food sources. International agencies, such as the Food and Agriculture Organization (FAO), have focused their attention on the consumption of edible insects, in particular, regarding their nutritional value and possible biological, toxicological, and allergenic risks, wishing the development of analytical methods to verify the authenticity, quality, and safety of insect-based products. Edible insects are rich in proteins, fats, fiber, vitamins, and minerals but also seem to contain large amounts of polyphenols able to have a key role in specific bioactivities. Therefore, this review is an overview of the potential of edible insects as a source of bioactive compounds, such as polyphenols, that can be a function of diet but also related to insect chemical defense. Currently, insect phenolic compounds have mostly been assayed for their antioxidant bioactivity; however, they also exert other activities, such as anti-inflammatory and anticancer activity, antityrosinase, antigenotoxic, and pancreatic lipase inhibitory activities.

Quality of T-Cell Response to SARS-CoV-2 mRNA Vaccine in ART-Treated PLWH.

We investigated specific humoral and T-cell responses in people living with HIV (PLWH) before (T0), after two (T1) and after six months (T2) from the third dose of the BNT162b2 vaccine. Healthy donors (HD) were enrolled. The specific humoral response was present in most PLWH already after the second dose, but the third dose increased both the rate of response and its magnitude. Collectively, no significant differences were found in the percentage of responding T-cells between PLWH and HD. At T0, stratifying PLWH according to CD4 cell count, a lower percentage of responding T-cells in <200 cells/µL subgroup compared to >200 cells/µL one was observed. At T1, this parameter was comparable between the two subgroups, and the same result was found at T2. However, the pattern of co-expression of IFNγ, IL2 and TNFα in PLWH was characterized by a higher expression of TNFα, independently of CD4 cell count, indicating a persistent immunological signature despite successful ART. mRNA vaccination elicited a specific response in most PLWH, although the cellular one seems qualitatively inferior compared to HD. Therefore, an understanding of the T-cell quality dynamic is needed to determine the best vaccination strategy and, in general, the capability of immune response in ART-treated PLWH.

Multiple sclerosis-disease modifying therapies affect humoral and T-cell response to mRNA COVID-19 vaccine.

Background: The mRNA vaccines help protect from COVID-19 severity, however multiple sclerosis (MS) disease modifying therapies (DMTs) might affect the development of humoral and T-cell specific response to vaccination. Methods: The aim of the study was to evaluate humoral and specific T-cell response, as well as B-cell activation and survival factors, in people with MS (pwMS) under DMTs before (T0) and after two months (T1) from the third dose of vaccine, comparing the obtained findings to healthy donors (HD). All possible combinations of intracellular IFNγ, IL2 and TNFα T-cell production were evaluated, and T-cells were labelled "responding T-cells", those cells that produced at least one of the three cytokines of interest, and "triple positive T-cells", those cells that produced simultaneously all the three cytokines. Results: The cross-sectional evaluation showed no significant differences in anti-S antibody titers between pwMS and HD at both time-points. In pwMS, lower percentages of responding T-cells at T0 (CD4: p=0.0165; CD8: p=0.0022) and triple positive T-cells at both time-points compared to HD were observed (at T0, CD4: p=0.0007 and CD8: p=0.0703; at T1, CD4: p=0.0422 and CD8: p=0.0535). At T0, pwMS showed higher plasma levels of APRIL, BAFF and CD40L compared to HD (p<0.0001, p<0.0001 and p<0.0001, respectively) and at T1, plasma levels of BAFF were still higher in pwMS compared to HD (p=0.0022).According to DMTs, at both T0 and T1, lower anti-S antibody titers in the depleting/sequestering-out compared to the enriching-in pwMS subgroup were found (p=0.0410 and p=0.0047, respectively) as well as lower percentages of responding CD4+ T-cells (CD4: p=0.0394 and p=0.0004, respectively). Moreover, the depleting/sequestering-out subgroup showed higher percentages of IFNγ-IL2-TNFα+ T-cells at both time-points, compared to the enriching-in subgroup in which a more heterogeneous cytokine profile was observed (at T0 CD4: p=0.0187; at T0 and T1 CD8: p =0.0007 and p =0.0077, respectively). Conclusion: In pwMS, humoral and T-cell response to vaccination seems to be influenced by the different DMTs. pwMS under depleting/sequestering-out treatment can mount cellular responses even in the presence of a low positive humoral response, although the cellular response seems qualitatively inferior compared to HD. An understanding of T-cell quality dynamic is needed to determine the best vaccination strategy and in general the capability of immune response in pwMS under different DMT.

Evaluation of Immunogenicity to Three Doses of the SARS-CoV-2 BNT162b2 mRNA Vaccine in Lung Transplant Patients.

The aim of the study was to explore the humoral and T-cell response in lung transplant (LuT) patients. Two-time points were considered, before (T0) and after (Tpost) the third dose of the BNT162b2 mRNA vaccine, comparing LuT with healthy donors (HD). LuT patients showed a lower serologic response against SARS-CoV-2 compared with HD at both time-points (p = 0.0001 and p = 0.0011, respectively). A lower percentage of IFNγ+orIL2+orTNFα+CD4+ and CD8+ T-cells LuT patients was observed in LuT patients compared with HD at T0 (CD4+: p = 0.0001; CD8+: p = 0.0005) and Tpost (CD4+: p = 0.0028; CD8+: p = 0.0114), as well as in the percentage of IFNγ+IL2+TNFα+CD4+ T-cells (T0: p = 0.0247; Tpost: p = 0.0367). Finally, at Tpost, a lower percentage of IFNγ+IL2+TNFα+ CD8+ T-cells in LuT patients compared with HD was found (p = 0.0147). LuT patients were stratified according to the lowest cut-off value for the detection of a humoral response (4.81 BAU/mL) at T0, into responder (R) and non-responder (NR) groups. In the R group, no differences in the percentage of IFNγ+or IL2+orTNFα+ and IFNγ+IL2+TNFα+CD4+ and CD8+ T-cells compared with HD at both time-points were observed. Otherwise, in the NR group, lower percentages of IFNγ+IL2+TNFα+CD4+ T-cells compared with the R group (T0: p = 0.0159; Tpost: p = 0.0159), as well as compared with the HD, at both time-points, were observed (T0: p = 0.0064; Tpost: p = 0.0064). These data seem to confirm that some LuT patients can mount cellular responses even in the absence of a positive humoral response (>33.8 BAU/mL), although this cellular response is dysfunctional and partially detrimental.

Bioplastics: A new analytical challenge.

Even though petroleum-based plastics are advantageous in complying with the performance requirements in many applications, these are related, throughout their life cycle, to several environmental problems, including greenhouse gas emissions and persistence in marine and terrestrial environments. Therefore, the preservation of natural resources and climate change is considered worldwide, the main reason for which is necessary to reduce consumption and dependence on fossil-based materials. Biopolymers (PLA, PHAs, etc.) are examples of plastics whose use is grown exponentially over the years because of the improvements of their physical and mechanical properties using additives of various nature and depending on the scope of application. This review aims to discuss various ways of biopolymer degradation, to evaluate if they represent a new Frontier in eco-sustainability or rather a re-proposal of old problems. Related to this topic, we also have focussed our attention on the different methods for the quantitative analysis of bioplastics, or their degradation by-products, comparing and evaluating the advantages and disadvantages of each technique.

Determination of trace levels of organic fining agents in wines: Latest and relevant findings.

The production of red wine plays a key role in the local and international economies of several nations. During the winemaking process, to clarify the final product, before bottling, and to remove undesired substances (proteins, phenols, and tannins), fining agents are commonly added to wines. These substances have different origins (animal and vegetable proteins or mineral compounds), and they show a potential risk for the health of allergic subjects. For these reasons, the residues of fining agents, constituted by exogenous proteins based on gluten, egg, and milk proteins, should not be present in the final product and their trace residues should be quantified with accuracy. In the last decade, several analytical approaches have been developed for their quantitative determination using different sample treatment protocols and analytical techniques. These methods are based on liquid chromatography coupled with mass spectrometry or enzyme-linked immunosorbent assays (ELISAs). Recently, biosensors have been proposed as a potential alternative to immunoassay approaches, allowing rapid, cheap, and simple multi-residue detection. This short review aimed to report the most recent and relevant findings in the field.

Mass Spectrometry-Based Peptide Profiling of Haemolymph from Pterostichus melas Exposed to Pendimethalin Herbicide.

Pendimethalin-based herbicides are used worldwide for pre-emergence selective control of annual grasses and weeds in croplands. The endurance of herbicides residues in the environment has an impact on the soil biodiversity and fertility, also affecting non-target species, including terrestrial invertebrates. Carabid beetles are known as natural pest control agents in the soil food web of agroecosystems, and feed on invertebrates and weed seeds. Here, a mass spectrometry untargeted profiling of haemolymph is used to investigate Pterostichus melas metabolic response after to pendimethalin-based herbicide exposure. Mass spectrometric data are examined with statistical approaches, such as principal component analysis, for possible correlation with biological effects. Those signals with high correlation are submitted to tandem mass spectrometry to identify the associated biomarker. The time course exposure showed many interesting findings, including a significant downregulation of related to immune and defense peptides (M-lycotoxin-Ls4a, Peptide hormone 1, Paralytic peptide 2, and Serine protease inhibitor 2). Overall, the observed peptide deregulations concur with the general mechanism of uptake and elimination of toxicants reported for Arthropods.

Serological Response and Relationship with Gender-Sensitive Variables among Healthcare Workers after SARS-CoV-2 Vaccination.

Vaccine-induced immunity is a key strategy in the long-term control of the COVID-19 pandemic. The aim of our study was to explore the relationship between mRNA vaccine-induced antibodies and gender-sensitive variables among healthcare workers. Two thousand-sixty-five volunteers who received the BNT162b2 vaccine were enrolled in the study and followed up. Demographic, clinical, and social variables (educational level, marital status, occupation, childcare) were evaluated through a self-administered questionnaire. Anti-Spike (S) IgG were measured at 1 month (T1) and at 5 months (T2) after the second vaccine dose. At T1, median anti-S IgG values were 693 [394−>800] AU/mL (1 AU = 2.6 BAU). Values > 800 AU/mL (2080 BAU/mL) were directly associated with a previous COVID-19 (p < 0.001) infection and inversely with age (p < 0.001), smoking habit (p < 0.001), and autoimmune diseases (p < 0.001). At T2, a significant decreasing in anti-S IgG values was observed (187 [81−262] AU/mL), with a median decrease of 72 [60−82]%. On multivariate data analysis, a reduction of more than 82% was directly associated with male sex (p < 0.021), age (p < 0.001), smoking (p = 0.038), hypertension (p = 0.042), and, inversely, with previous COVID-19 infection (p < 0.001) and being "cohabiting" (p = 0.005). Our findings suggest that demographic, clinical, and social variables play a role in anti-S IgG values decreasing in long-term follow up and should be considered to find personalized vaccine schedules.

Speciation Study on O-Phosphorylethanolamine and O-Phosphorylcholine: Acid-Base Behavior and Mg2+ Interaction.

In the present study, the acid-base behavior of compounds constituting the headgroups of biomembranes, O-phosphorylethanolamine (PEA), and O-phosphorylcholine (PPC) was investigated by potentiometric titrations in NaCl aqueous solutions at different temperatures (15 ≤ t/°C ≤ 37) and ionic strength (0.15 ≤ I/mol L-1 ≤ 1) values. The complexation properties and the speciation of these ligands with Mg2+ were defined under different temperatures (15 ≤ t/°C ≤ 37) and I = 0.15 mol L-1. The results evidenced the formation of three species for PEA, namely, MLH2, MLH, and ML and two species for PPC, namely, MLH and ML. 1H-NMR titrations were performed on solutions containing ligand and metal-ligand solutions at t = 25°C and I = 0.15 mol L-1. The estimated values of ligand protonation and complex formation constants and the speciation model are in accordance with the potentiometric data. The enthalpy changes were also determined at t = 25°C and I = 0.15 mol L-1 by the dependence of formation constants on the temperature, confirming the electrostatic nature of the interactions. Matrix-assisted laser desorption mass spectrometry (MALDI-MS) was applied for the characterization of Mg2+-L systems (L = PEA or PCC). MS/MS spectra of free ligands and of Mg2+-L species were obtained. The observed fragmentation patterns of both Mg2+-L systems allowed elucidating the interaction mechanism that occurs via the phosphate group generating a four-membered cycle.