Low-Dose Occupational Exposure to Ionizing Radiation and Cardiovascular Effects: A Narrative Review

Historically, non-cancer diseases have not been considered a health risk following low-dose exposure to ionizing radiation. However, it is now well known that high-dose ionizing radiation causes cardiovascular disease, and emerging epidemiological evidence suggests an excess risk of non-cancer diseases even following exposure to lower doses of ionizing radiation than previously thought. In fact, the evidence is strongest for cardiovascular disease (CVD). The aim of this review was to report the most representative studies and data on the risk of CVD from low-dose radiation in people with occupational exposure. We reported the results of 27 articles selected from a database search of 1151 studies. The results show a complex evidence landscape on the relationship between radiation exposure and cardiovascular disease. In general, published papers show a positive association between ionizing radiation exposure and dermal microcirculation damage, ischemic heart disease, and cerebrovascular disease. Overall, they highlight the need for comprehensive and detailed research to clarify this relationship. Due to limited statistical power, the dose-risk relationship below 0.5 Gy is inconclusive, but if this relationship is found to have no threshold, it could have a significant impact on current estimates of health risks at low doses.

Do Media Extracellular Vesicles and Extracellular Vesicles Bound to the Extracellular Matrix Represent Distinct Types of Vesicles?

Mineralization-competent cells, including hypertrophic chondrocytes, mature osteoblasts, and osteogenic-differentiated smooth muscle cells secrete media extracellular vesicles (media vesicles) and extracellular vesicles bound to the extracellular matrix (matrix vesicles). Media vesicles are purified directly from the extracellular medium. On the other hand, matrix vesicles are purified after discarding the extracellular medium and subjecting the cells embedded in the extracellular matrix or bone or cartilage tissues to an enzymatic treatment. Several pieces of experimental evidence indicated that matrix vesicles and media vesicles isolated from the same types of mineralizing cells have distinct lipid and protein composition as well as functions. These findings support the view that matrix vesicles and media vesicles released by mineralizing cells have different functions in mineralized tissues due to their location, which is anchored to the extracellular matrix versus free-floating.

Pulmonary function assessment after COVID-19 in vaccinated healthcare workers

COVID-19 typically presents with flu-like symptoms due to the viral infection itself. The most severe cases are characterised by lung damage, an important factor in fatal outcome due to alveolar damage. In some cases, patients develop a long COVID with persistent symptoms of chest pain and fatigue. Causes, including organ damage or inflammation, are being investigated. Clinical outcomes are variable and permanent lung damage is not fully understood, while vaccination is effective against severe infection but its effect on respiratory function in mild cases remains uncertain. This retrospective study aims to analyse changes in lung function in HCWs who had COVID-19 between 2020 and 2022, comparing their spirometric test results before and after the pandemic and taking into account their vaccination status. 321 HCWs were included in the study. The study examined spirometric parameters both before and after the pandemic, and all measured outcomes except the FEV1/FVC ratio showed a significant decrease during the study period. We then assessed the association between SARS-CoV-2 infection and changes in lung function parameters, analysing infections in 2020, 2021 and 2022 separately. We found a statistically significant difference in Forced vital capacity (FVC) between infected and non-infected subjects in 2020 and 2021, but not in 2022. To evaluate the protective effect of SARS-CoV-2 vaccination on respiratory function, a linear regression analysis was performed using changes in FVC, Forced expiratory volume in 1 s (FEV1), FVC/FEV1 ratio and Peak expiratory flow (PEF) as dependent variables. The analysis showed that the decline in FVC was significantly lower in subjects who had been vaccinated prior to infection. The study concludes that subclinical SARS-CoV-2 infections in 2020 and 2021 worsened respiratory parameters (FVC and FEV1), but vaccination protected against these effects. Even healthy individuals with previous infections showed respiratory changes, with vaccination providing protection, especially for FVC decline. This highlights the importance of vaccinating healthcare workers against COVID-19.

Rubella Vaccine Uptake among Women of Childbearing Age in Healthcare Settings

BACKGROUND

Rubella is a contagious viral infection that occurs most often in children and young adults. Rubella is the leading vaccine-preventable cause of birth defects. Rubella infection in pregnant women may cause fetal death or congenital defects known as congenital rubella syndrome. There is no specific treatment for rubella, but the disease is preventable by vaccination with an efficacy of over 95%. Vaccination coverage is still below the recommended levels and many cases have occurred worldwide. The COVID-19 pandemic has had a negative impact on the immunization programs and the quality of disease surveillance worldwide. Operators of the healthcare setting are at increased risk of infection due to their work duties and should receive preventive vaccination or serologic protection to work in a healthcare setting.

AIMS

To evaluate the serological evidence of rubella IgG antibodies in female healthcare operators of childbearing age, to assess the risk of a breakthrough infection and the need for an additional dose of vaccine.

METHODS

We collected age and antibody titers from 449 young female operators aged <50 years who underwent the periodic surveillance at the Occupational Medicine Unit of the Policlinico Tor Vergata, Rome, from January to July 2022. Subjects were considered immune if the anti-rubella IgG titer was >11.00 IU/mL.

RESULTS

The rate of serologically unprotected subjects was 9.13% (41/449). The mean age of protected subjects was 26.93 years, while the mean age of unprotected subjects was 28.24 years. Age did not correlate with mean titer on statistical analysis (p = 0.10). The acceptance rate among unprotected operators was 31.7%. A positive attitude towards vaccination was found in 11/28 (39.3%) of the unvaccinated subjects, while a negative tendency was found in 2/28 (7.1%) of these subjects; most of the unvaccinated operators 15/28 (53.6%) prefer to postpone the administration of the vaccine. When compared with a similar population from the pre-pandemic period, the actual proportion of immune female subjects was not significantly different from that found in 2019 (90.87% vs. 90.3%).

CONCLUSIONS

Protection against rubella was suboptimal among female healthcare workers of childbearing age. Acceptance of the rubella vaccine among these operators was low. Most of those who were hesitant intended to postpone the vaccination, while a minority had negative attitudes toward vaccination. A policy of mandatory vaccination policy should overcome the reluctance of operators.

Protective Anti-HBs Antibodies and Response to a Booster Dose in Medical Students Vaccinated at Childhood

The immune system in humans is regulated by the circadian rhythm. Published studies have reported that the time of vaccination is associated with the immune response to vaccine for some pathogens. Our study aimed to evaluate the association between time of dose administration of challenge HBV vaccine and seroconversion for anti-HBs in medical students vaccinated at birth who were found to be unprotected at pre-training screening. Humoral protection for HBV was assessed in 885 medical students vaccinated during childhood. In total, 359 (41.0%) of them showed anti-HBs titer < 10 UI/mL and received a challenge dose of HBV vaccine followed by post-vaccination screening 30-60 days later. The challenge dose elicited a protective immune response (anti-HBs IgG titer > 10 UI/mL) in 295 (83.8%) individuals. Seroconversion was significantly associated with female gender and time of vaccination after controlling for age group and nationality at logistic regression analysis. Students who received the booster dose in the morning had a higher response rate than those who received the vaccine in the afternoon (OR 1.93; 95% C.I. 1.047-3.56: p < 0.05). This finding suggests that morning administration of the HBV booster may result in a better immune response in susceptible individuals.

Measles vaccine uptake among Italian medical students compared to the pre-COVID-19 era

The COVID-19 pandemic has severely affected health systems worldwide and raised the issue of vaccine hesitancy. In 2022, the World Health Organization reported an outbreak of measles infection among people over 20 years of age in the European Region. Previous studies found low rates of measles immunization among Italian healthcare workers (HCWs) and medical students. Vaccine hesitancy is a relevant cause of low immunization rate among HCWs and the general population. We aim to evaluate the measles vaccine uptake among medical students of a large teaching hospital, compared to the pre-pandemic period. This is a retrospective observational study, that evaluated the immune status and the vaccine acceptance rate for measles in medical students at the University of Tor Vergata, Rome, who underwent occupational health surveillance from 1 January to 1 December 2022. We also compared the data with the results of a pre-pandemic survey conducted in 2018. Vaccine uptake among unprotected medical students was 59.5%. The data showed no significant difference in vaccine uptake compared with the pre-COVID-19 period. Conversely, the rate of serologically immune subjects to measles increased from 89.66% in 2018 to 97.45% in 2022 as a result of the recent mandatory vaccination policy. Despite efforts to tackle vaccine hesitancy during the COVID-19 pandemic, measles vaccine uptake is still low among young adults starting their medical training, and their compliance with free workplace vaccination offers is suboptimal. Occupational health services should raise awareness among workers and work together to implement strategies to achieve comprehensive measles vaccination coverage among occupational health workers.

Serological Evaluation for Measles among Italian and Foreign Medical Students in a University Hospital in Rome

BACKGROUND

Measles infection in the hospital setting is a major issue. Despite the availability of an effective vaccine, measles outbreaks continue to occur in some European countries. We aimed to evaluate the immunological status of medical students attending the Tor Vergata Polyclinic (PTV).

METHODS

Measles antibodies titers were assessed by venipuncture on a sample of 2717 medical students who underwent annual health surveillance visits from January 2021 to March 2023. Subjects showing serum IgG values above 1.0 S/CO were considered serologically protected. Personal data, country of origin, and main demographic characteristic were also collected.

RESULTS

66.7% (1467 Italian and 346 foreign) of medical students showed protective IgG antibodies levels. Female students were serologically immune more frequently than males (68.6% vs. 63.3%; p < 0.01 at Chi2). The mean antibody titer was 1.72 S/CO, significantly higher in females than males (1.67 vs. 1.75, respectively; p < 0.05), and significantly related to age (p < 0.01). Albanian students, who were the largest foreign population in our study, showed a low serological protection rate (40/90: 44.4%).

CONCLUSIONS

The proportion of serologically non-immune students is high, raising concerns about the possible risk of hospital transmission. Substantial differences in the rate of immunity have been found between subjects coming from different parts of Europe and the world. Pre-training assessment of all medical students and vaccination of susceptible individuals is highly recommended, particularly for those from low immunization rate countries.

A New Algorithm for Estimating a Noiseless, Evenly Sampled, Heart Rate Modulating Signal

Heart rate variability (HRV) is commonly intended as the variation in the heart rate (HR), and it is evaluated in the time and frequency domains with various well-known methods. In the present paper, the heart rate is considered as a time domain signal, at first as an abstract model in which the HR is the instantaneous frequency of an otherwise periodic signal, such as with an electrocardiogram (ECG). In this model, the ECG is assumed to be a frequency modulated signal, or carrier signal, where HRV or HRV(t) is the time-domain signal which is frequency modulating the carrier ECG signal around its average frequency. Hence, an algorithm able to frequency demodulate the ECG signal to extract the signal HRV(t) is described, with possibly enough time resolution to analyse fast time-domain variations in the instantaneous HR. After exhaustive testing of the method on simulated frequency modulated sinusoidal signals, the new procedure is eventually applied on actual ECG tracings for preliminary nonclinical testing. The purpose of the work is to use this algorithm as a tool and a more reliable method for the assessment of heart rate before any further clinical or physiological analysis.

Hypocalcemia is associated with adverse outcomes in patients hospitalized with COVID-19

PURPOSE

Calcium ions are involved in the regulation of several cellular processes and may also influence viral replication. Hypocalcemia has been frequently reported during infectious diseases and in critically ill patients, including also COVID-19 patients, significantly related with the pro-inflammatory state and mortality. The aim of this study is to investigate the prevalence of hypocalcemia at admission in patients hospitalized for COVID-19 (Coronavirus disease 2019) and to evaluate association of hypocalcemia with in-hospital COVID-19 outcomes.

METHODS

Retrospective analysis on 118 consecutive patients, hospitalized for COVID-19 between March and May 2020. Clinical characteristics, inflammation markers, biochemical routine and mineral metabolism parameters at admission were collected. Hypocalcemia was defined as total serum calcium <2.2 mmol/L. Population was stratified by tertiles of total serum calcium. Primary outcome was the composite of in-hospital death or admission to intensive care unit (ICU). Secondary outcomes included in-hospital death, admission to ICU and need for non-invasive ventilation as separate events. Associations were tested by logistic regression and Cox-regression analysis with survival curves.

RESULTS

Overall prevalence of hypocalcemia was 76.6%, with just 6.7% of patients reporting levels of 25-(OH)-vitamin D > 30 ng/ml. Total serum calcium was inversely related with selected inflammatory biomarkers (p < 0.05) and poorer outcome of COVID-19 during hospitalization. Lower tertile of total calcium (≤2.02 mmol/L) had increased risk of in-hospital mortality (HR 2.77; 1.28-6.03, p = 0.01) compared with other groups.

CONCLUSION

Total serum calcium detected on admission is inversely related with proinflammatory biomarkers of severe COVID-19 and is useful to better define risk stratification for adverse in-hospital outcome.

Evaluation of the accuracy in the mucosal detection of anti-SARS-CoV-2 antibodies in nasal secretions and saliva

COVID-19 vaccination with mRNA vaccines induces immune responses capable of neutralizing SARS-CoV-2. Commercially available serological anti-SARS-CoV-2 quantitative and neutralizing assays are essential for the determination of immune responses to vaccines. Nevertheless, at present there is a lack of validated tests to assess the mucosal response to COVID-19 vaccination and standardized analytic and pre-analytic methods have not yet been defined. The aim of our study was to evaluate the accuracy of two diagnostic immunoassays for COVID-19 (ELISA for IgA-S1 and chemiluminescent assay for IgG-RBD) on serum, saliva, and nasal secretions, by the enrollment of three study populations (healthy controls, vaccinated subjects, and subjects recovered from COVID-19 infection). In order to obtain an appropriate cut-off value for the biological matrices studied, ROC curve analyses were performed. Data demonstrate that the analytical and pre-analytical method we have developed can provide accurate and reliable results for the detection of anti-SARS-CoV-2 mucosal specific antibodies (IgA-S1 and IgG-RBD) on saliva and, as a novelty, on nasal secretions, either after COVID-19 infection or in vaccinated subjects.

Correction: Guerrieri et al. Nasal and Salivary Mucosal Humoral Immune Response Elicited by mRNA BNT162b2 COVID-19 Vaccine Compared to SARS-CoV-2 Natural Infection. Vaccines 2021, 9, 1499

The authors wish to make the following corrections to this paper [...].

A novel, integrated approach for understanding and investigating Healthcare Associated Infections: A risk factors constellation analysis

INTRODUCTION

Healthcare-associated infections (HAIs) and antimicrobial resistance (AMR) are major public health threats in upper- and lower-middle-income countries. Electronic health records (EHRs) are an invaluable source of data for achieving different goals, including the early detection of HAIs and AMR clusters within healthcare settings; evaluation of attributable incidence, mortality, and disability-adjusted life years (DALYs); and implementation of governance policies. In Italy, the burden of HAIs is estimated to be 702.53 DALYs per 100,000 population, which has the same magnitude as the burden of ischemic heart disease. However, data in EHRs are usually not homogeneous, not properly linked and engineered, or not easily compared with other data. Moreover, without a proper epidemiological approach, the relevant information may not be detected. In this retrospective observational study, we established and engineered a new management system on the basis of the integration of microbiology laboratory data from the university hospital "Policlinico Tor Vergata" (PTV) in Italy with hospital discharge forms (HDFs) and clinical record data. All data are currently available in separate EHRs. We propose an original approach for monitoring alert microorganisms and for consequently estimating HAIs for the entire period of 2018.

METHODS

Data extraction was performed by analyzing HDFs in the databases of the Hospital Information System. Data were compiled using the AREAS-ADT information system and ICD-9-CM codes. Quantitative and qualitative variables and diagnostic-related groups were produced by processing the resulting integrated databases. The results of research requests for HAI microorganisms and AMR profiles sent by the departments of PTV from 01/01/2018 to 31/12/2018 and the date of collection were extracted from the database of the Complex Operational Unit of Microbiology and then integrated.

RESULTS

We were able to provide a complete and richly detailed profile of the estimated HAIs and to correlate them with the information contained in the HDFs and those available from the microbiology laboratory. We also identified the infection profile of the investigated hospital and estimated the distribution of coinfections by two or more microorganisms of concern. Our data were consistent with those in the literature, particularly the increase in mortality, length of stay, and risk of death associated with infections with Staphylococcus spp, Pseudomonas aeruginosa, Klebsiella pneumoniae, Clostridioides difficile, Candida spp., and Acinetobacter baumannii. Even though less than 10% of the detected HAIs showed at least one infection caused by an antimicrobial resistant bacterium, the contribution of AMR to the overall risk of increased mortality was extremely high.

CONCLUSIONS

The increasing availability of health data stored in EHRs represents a unique opportunity for the accurate identification of any factor that contributes to the diffusion of HAIs and AMR and for the prompt implementation of effective corrective measures. That said, artificial intelligence might be the future of health data analysis because it may allow for the early identification of patients who are more exposed to the risk of HAIs and for a more efficient monitoring of HAI sources and outbreaks. However, challenges concerning codification, integration, and standardization of health data recording and analysis still need to be addressed.

Main Predictors of COVID-19 Vaccination Uptake among Italian Healthcare Workers in Relation to Variable Degrees of Hesitancy: Result from a Cross-Sectional Online Survey

Background: Hesitancy remains one of the major hurdles to vaccination, regardless of the fact that vaccines are indisputable preventive measures against many infectious diseases. Nevertheless, vaccine hesitancy or refusal is a growing phenomenon in the general population as well as among healthcare workers (HCWs). Many different factors can contribute to hesitancy to COVID-19 vaccination in the HCWs population, including socio-demographic characteristics (female gender, low socio-economical status, lower age), individual beliefs regarding vaccine efficacy and safety, as well as other factors (occupation, knowledge about COVID-19, etc.). Understanding the determinants of accepting or refusing the COVID-19 vaccination is crucial to plan specific interventions in order to increase the rate of vaccine coverage among health care workers. Methods: We conducted a cross-sectional online survey on HCWs in seventeen Italian regions, between 30 June and 4 July 2021, in order to collect information about potential factors related to vaccine acceptance and hesitancy. Results: We found an overall vaccine uptake rate of 96.4% in our sample. Acceptance was significantly related to job task, with physicians showing the highest rate of uptake compared to other occupations. At univariate analysis, the HCWs population’s vaccine hesitancy was significantly positively associated with fear of vaccination side effects (p < 0.01), and negatively related to confidence in the safety and efficacy of the vaccine (p < 0.01). Through multivariate analysis, we found that only the fear of possible vaccination side effects (OR: 4.631, p < 0.01) and the confidence in vaccine safety and effectiveness (OR: 0.35 p < 0.05) remained significantly associated with hesitancy. Conclusion: Action to improve operator confidence in the efficacy and safety of the vaccine should improve the acceptance rate among operators.

Shedding Light on the Role of Na,K-ATPase as a Phosphatase during Matrix-Vesicle-Mediated Mineralization

Matrix vesicles (MVs) contain the whole machinery necessary to initiate apatite formation in their lumen. We suspected that, in addition to tissue-nonspecific alkaline phosphatase (TNAP), Na,K,-ATPase (NKA) could be involved in supplying phopshate (P_i) in the early stages of MV-mediated mineralization. MVs were extracted from the growth plate cartilage of chicken embryos. Their average mean diameters were determined by Dynamic Light Scattering (DLS) (212 ± 19 nm) and by Atomic Force Microcopy (AFM) (180 ± 85 nm). The MVs had a specific activity for TNAP of 9.2 ± 4.6 U·mg^-1 confirming that the MVs were mineralization competent. The ability to hydrolyze ATP was assayed by a colorimetric method and by ³¹P NMR with and without Levamisole and SBI-425 (two TNAP inhibitors), ouabain (an NKA inhibitor), and ARL-67156 (an NTPDase1, NTPDase3 and Ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) competitive inhibitor). The mineralization profile served to monitor the formation of precipitated calcium phosphate complexes, while IR spectroscopy allowed the identification of apatite. Proteoliposomes containing NKA with either dipalmitoylphosphatidylcholine (DPPC) or a mixture of 1:1 of DPPC and dipalmitoylphosphatidylethanolamine (DPPE) served to verify if the proteoliposomes were able to initiate mineral formation. Around 69-72% of the total ATP hydrolysis by MVs was inhibited by 5 mM Levamisole, which indicated that TNAP was the main enzyme hydrolyzing ATP. The addition of 0.1 mM of ARL-67156 inhibited 8-13.7% of the total ATP hydrolysis in MVs, suggesting that NTPDase1, NTPDase3, and/or NPP1 could also participate in ATP hydrolysis. Ouabain (3 mM) inhibited 3-8% of the total ATP hydrolysis by MVs, suggesting that NKA contributed only a small percentage of the total ATP hydrolysis. MVs induced mineralization via ATP hydrolysis that was significantly inhibited by Levamisole and also by cleaving TNAP from MVs, confirming that TNAP is the main enzyme hydrolyzing this substrate, while the addition of either ARL-6715 or ouabain had a lesser effect on mineralization. DPPC:DPPE (1:1)-NKA liposome in the presence of a nucleator (PS-CPLX) was more efficient in mineralizing compared with a DPPC-NKA liposome due to a better orientation of the NKA active site. Both types of proteoliposomes were able to induce apatite formation, as evidenced by the presence of the 1040 cm^-1 band. Taken together, the findings indicated that the hydrolysis of ATP was dominated by TNAP and other phosphatases present in MVs, while only 3-8% of the total hydrolysis of ATP could be attributed to NKA. It was hypothesized that the loss of Na/K asymmetry in MVs could be caused by a complete depletion of ATP inside MVs, impairing the maintenance of symmetry by NKA. Our study carried out on NKA-liposomes confirmed that NKA could contribute to mineral formation inside MVs, which might complement the known action of PHOSPHO1 in the MV lumen.

Impact of light therapy on rotating night shift workers: the EuRhythDia study

AIMS

Disturbances in circadian rhythms may promote cardiometabolic disorders in rotating night shift workers (r-NSWs). We hypothesized that timed light therapy might reverse disrupted circadian rhythms and glucose intolerance observed among r-NSWs).

METHODS

R-NSWs were randomly assigned to a protocol that included 12 weeks on followed by 12 weeks off light therapy (n = 13; 6 men; mean age, 39.5 ± 7.3 years) or a no-treatment control group (n = 9; 3 men; mean age 41.7 ± 6.3 years). Experimental and control participants underwent identical metabolic evaluations that included anthropometric, metabolic (including oral glucose tolerance tests), lipid, and inflammation-associated parameters together with an assessment of sleep quality and expression of circadian transcription factors REV-ERBα and BMAL1 in peripheral blood mononuclear cells (PBMCs) at baseline, 12 weeks, and 24 weeks of the protocol.

RESULTS

Twelve weeks of warm white-light exposure (10,000 lx at 35 cm for 30 min per day) had no impact on sleep, metabolic, or inflammation-associated parameters among r-NSWs in the experimental group. However, our findings revealed significant decreases in REV-ERBα gene expression (p = 0.048) and increases in the REV-ERBα/BMAL1 ratio (p = 0.040) compared to baseline in PBMCs isolated from this cohort. Diminished expression of REV-ERBα persisted, although the REV-ERBα/BMAL1 ratio returned to baseline levels after the subsequent 12-day wash-out period.

CONCLUSIONS

Our results revealed that intermittent light therapy had no impact on inflammatory parameters or glucose tolerance in a defined cohort of r-NSWs. However, significant changes in the expression of circadian clock genes were detected in PBMCs of these subjects undergoing light therapy.

Effects of Ultramicronized Palmitoylethanolamide (um-PEA) in COVID-19 Early Stages: A Case–Control Study

Ultramicronized palmitoylethanolamide (um-PEA), a compound with antioxidant, anti-inflammatory and neuroprotective properties, appears to be a potential adjuvant treatment for early stages of Coronavirus disease 2019 (COVID-19). In our study, we enrolled 90 patients with confirmed diagnosis of COVID-19 that were randomized into two groups, homogeneous for age, gender and BMI. The first group received oral supplementation based on um-PEA at a dose of 1800 mg/day for a total of 28 days; the second group was the control group (R.S. 73.20). At baseline (T0) and after 28 days of um-PEA treatment (T1), we monitored: routine laboratory parameters, inflammatory and oxidative stress (OS) biomarkers, lymphocytes subpopulation and COVID-19 serological response. At T1, the um-PEA-treated group presented a significant reduction in inflammation compared to the control group (CRP p = 0.007; IL-6 p = 0.0001; neutrophils to lymphocytes ratio p = 0.044). At T1, the controls showed a significant increase in OS compared to the treated group (FORT p = 0.05). At T1, the um-PEA group exhibited a significant decrease in D-dimer levels (p = 0.0001) and higher levels of IgG against SARS-CoV-2 (p = 0.0001) compared to the controls. Our data demonstrated, in a randomized clinical trial, the beneficial effects of um-PEA in both asymptomatic and mild-symptomatic patients related to reductions in inflammatory state, OS and coagulative cascade alterations.

Health and Economic Impact of Atrial Fibrillation of Workers in Italy: Social Security Benefits

Background: The aim of this research was to analyze trends in social security applications in Italy as a result of the onset of atrial fibrillation, analyzing data pertaining to the classification of professions and assessing the economic impact on the social security system. Methods: We analyzed all applications for invalidity allowances and invalidity pensions throughout Italy over a 10-year period from 01.01.2009 to 31.12.2019, giving specific attention to all reports indicating atrial fibrillation as the principal diagnosis (Cod. ICD-9-CM 427.31). We then extracted the relative expenditure data for said benefits. The results of all analyses have been collated in tables. Results: Over the period in question, a total of 3468 applications for assistance were filed throughout Italy indicating a diagnosis of atrial fibrillation, of which 58% were rejected, 41% qualified for an invalidity allowance, and only 1.1% qualified for a pension. On average, every year, 1100 workers received social security benefits as a result of a diagnosis of atrial fibrillation, which equates to an average annual expenditure of EUR 10 million. A comparison of the data from the first observation year (2009) with data from the last (2019) shows a rising trend in the number of beneficiaries and consequently in expenses. Conclusions: The social security assistance provided by the Italian government by means of the National Institute of Social Security is fundamental to social cohesion and to those who are either permanently disabled from working or those with a significantly diminished earning capacity. This assistance is associated with a significant financial cost, which requires careful monitoring.

Reduced Titers of Circulating Anti-SARS-CoV-2 Antibodies and Risk of COVID-19 Infection in Healthcare Workers during the Nine Months after Immunization with the BNT162b2 mRNA Vaccine

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has had a tremendous impact on health services; hundreds of thousands of healthcare workers (HCWs) have died from coronavirus disease 2019 (COVID-19). The introduction of the BNT162b2 mRNA vaccine in Italy provided recipients with significant protection against COVID-19 within one to two weeks after the administration of the second of the two recommended doses. While the vaccine induces a robust T cell response, the protective role of factors and pathways other than those related to memory B cell responses to specific SARS-CoV-2 antigens remains unclear. This retrospective study aimed to evaluate the determinants of serological protection in a group of vaccinated HCWs (n = 793) by evaluating circulating levels of antiviral spike receptor-binding domain (S-RBD) antibodies during the nine-month period following vaccination. We found that 99.5% of the HCWs who received the two doses of the BNT162b2 vaccine developed protective antibodies that were maintained at detectable levels for as long as 250 days after the second dose of the vaccine. Multivariate analysis was performed on anti-S-RBD titers in a subgroup of participants (n = 173) that were evaluated twice during this period. The results of this analysis reveal that the antibody titer observed at the second time point was significantly related to the magnitude of the primary response, the time that had elapsed between the first and the second evaluation, and a previous history of SARS-CoV-2 infection. Of importance is the finding that despite waning antibody titers following vaccination, none of the study participants contracted severe COVID-19 during the observational period.

Nasal and Salivary Mucosal Humoral Immune Response Elicited by mRNA BNT162b2 COVID-19 Vaccine Compared to SARS-CoV-2 Natural Infection

SARS-CoV-2 antibody assays are crucial in managing the COVID-19 pandemic. Approved mRNA COVID-19 vaccines are well known to induce a serum antibody responses against the spike protein and its RBD. Mucosal immunity plays a major role in the fight against COVID-19 directly at the site of virus entry; however, vaccine abilities to elicit mucosal immune responses have not been reported. We detected anti-SARS-CoV-2 IgA-S1 and IgG-RBD in three study populations (healthy controls, vaccinated subjects, and subjects recovered from COVID-19 infection) on serum, saliva, and nasal secretions using two commercial immunoassays (ELISA for IgA-S1 and chemiluminescent assay for IgG-RBD). Our results show that the mRNA BNT162b2 vaccine Comirnaty (Pfizer/BioNTech, New York, NY, USA) determines the production of nasal and salivary IgA-S1 and IgG-RBD against SARS-CoV-2. This mucosal humoral immune response is stronger after the injection of the second vaccine dose compared to subjects recovered from COVID-19. Since there is a lack of validated assays on saliva and nasal secretions, this study shows that our pre-analytical and analytical procedures are consistent with the data. Our findings indicate that the mRNA COVID-19 vaccine elicits antigen-specific nasal and salivary immune responses, and that mucosal antibody assays could be used as candidates for non-invasive monitoring of vaccine-induced protection against viral infection.

Lactoferrin as Antiviral Treatment in COVID-19 Management: Preliminary Evidence

Lactoferrin (Lf), a multifunctional cationic glycoprotein synthesized by exocrine glands and neutrophils, possesses an in vitro antiviral activity against SARS-CoV-2. Thus, we conducted an in vivo preliminary study to investigate the antiviral effect of oral and intranasal liposomal bovine Lf (bLf) in asymptomatic and mild-to-moderate COVID-19 patients. From April 2020 to June 2020, a total of 92 mild-to-moderate (67/92) and asymptomatic (25/92) COVID-19 patients were recruited and divided into three groups. Thirty-two patients (14 hospitalized and 18 in home-based isolation) received only oral and intranasal liposomal bLf; 32 hospitalized patients were treated only with standard of care (SOC) treatment; and 28, in home-based isolation, did not take any medication. Furthermore, 32 COVID-19 negative, untreated, healthy subjects were added for ancillary analysis. Liposomal bLf-treated COVID-19 patients obtained an earlier and significant (p < 0.0001) SARS-CoV-2 RNA negative conversion compared to the SOC-treated and untreated COVID-19 patients (14.25 vs. 27.13 vs. 32.61 days, respectively). Liposomal bLf-treated COVID-19 patients showed fast clinical symptoms recovery compared to the SOC-treated COVID-19 patients. In bLf-treated patients, a significant decrease in serum ferritin, IL-6, and D-dimers levels was observed. No adverse events were reported. These observations led us to speculate a potential role of bLf in the management of mild-to-moderate and asymptomatic COVID-19 patients.

Skin sensitization among night shift and daytime healthcare workers: a cross sectional study

OBJECTIVE

Allergic contact dermatitis (ACD) in the healthcare sector is a major occupational health hazard. There are many reasons for a higher frequency of ACD in healthcare personnel compared to other populations: among others, simultaneous exposure to multiple substances, use of aggressive detergents and wet work. However, studies that systematically correlate skin symptoms with the presence of sensitization investigated through patch tests in specific categories of health workers are very rare and conflicting. Although some studies have reported a correlation between skin disease and night shift, the strength of the evidence is rather limited. The purpose of our study was to investigate by means of patch testing the skin sensitization (SS) to common allergens in the hospital setting in a group of healthcare workers (HCW) reporting symptoms related to dermatitis, according to their job activity and their shift status.

METHODS

132 HCWs visiting a health surveillance centre were investigated by means of specific questionnaire for dermatitis, followed by patch test evaluation including 40 haptens of the SIDAPA 2016 series.

RESULTS

Skin sensitization was observed in 1/3 of the subjects investigated by patch tests. The nursing job was strongly associated with cutaneous reactivity after controlling for the confounding of gender, age and other factors. Shift work was related to the prevalence of SS.

CONCLUSIONS

In our study, the nurse's role and shift work were significantly associated with the risk of cutaneous sensitization, in particular for common antigens.

Silica encapsulation of ZnO nanoparticles reduces their toxicity for cumulus cell-oocyte-complex expansion

Background

Metal oxide nanoparticles (NPs) are increasingly used in many industrial and biomedical applications, hence their impact on occupational and public health has become a concern. In recent years, interest on the effect that exposure to NPs may exert on human reproduction has grown, however data are still scant. In the present work, we investigated whether different metal oxide NPs interfere with mouse cumulus cell-oocyte complex (COC) expansion.

Methods

Mouse COCs from pre-ovulatory follicles were cultured in vitro in the presence of various concentrations of two types of TiO₂ NPs (JRC NM-103 and NM-104) and four types of ZnO NPs (JRC NM-110, NM-111, and in-house prepared uncoated and SiO₂-coated NPs) and the organization of a muco-elastic extracellular matrix by cumulus cells during the process named cumulus expansion was investigated.

Results

We show that COC expansion was not affected by the presence of both types of TiO₂ NPs at all tested doses, while ZnO NM-110 and NM-111 induced strong toxicity and inhibited COCs expansion at relatively low concentration. Medium conditioned by these NPs showed lower toxicity, suggesting that, beside ion release, inhibition of COC expansion also depends on NPs per se. To further elucidate this, we compared COC expansion in the presence of uncoated or SiO₂-coated NPs. Differently from the uncoated NPs, SiO₂-coated NPs underwent slower dissolution, were not internalized by the cells, and showed an overall lower toxicity. Gene expression analysis demonstrated that ZnO NPs, but not SiO₂-coated ZnO NPs, affected the expression of genes fundamental for COC expansion. Dosimetry analysis revealed that the delivered-to-cell mass fractions for both NPs was very low.

Conclusions

Altogether, these results suggest that chemical composition, dissolution, and cell internalization are all responsible for the adverse effects of the tested NPs and support the importance of a tailored, safer-by-design production of NPs to reduce toxicity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-021-00424-z.

Atherogenic Dyslipidemia on Admission Is Associated With Poorer Outcome in People With and Without Diabetes Hospitalized for COVID-19

OBJECTIVE

Identifying metabolic factors associated with critical disease can help to improve management of patients hospitalized for coronavirus disease 2019 (COVID-19). High triglycerides and low HDL levels characterize the atherogenic dyslipidemia closely related to insulin resistance and diabetes. We examined associations of atherogenic dyslipidemia detected on admission with outcome of COVID-19 during hospitalization.

RESEARCH DESIGN AND METHODS

We retrospectively analyzed clinical reports of 118 consecutive patients hospitalized for COVID-19 in Rome, Italy, between March and May 2020. Clinical characteristics, inflammation markers, and glucose and lipid metabolism parameters at admission were collected. Critical disease was defined as in-hospital death or need for endotracheal intubation. Associations were tested using logistic regression analysis.

RESULTS

Patients with critical COVID-19 (n = 43) were significantly older than those with noncritical disease (n = 75) and presented higher levels of fasting glucose, triglycerides, C-reactive protein, interleukin-6, procalcitonin, and d-dimer (P < 0.01 for all), whereas HDL levels were lower (P = 0.003). Atherogenic dyslipidemia was more frequent in patients with critical COVID-19 (46 vs. 24%, P = 0.011), as well as diabetes (37 vs. 19%, P = 0.026), and significantly associated with death or intubation (odds ratio 2.53 [95% CI 1.16-6.32], P = 0.018). Triglycerides were significantly associated with selected inflammatory biomarkers (P < 0.05 for all) and poorer outcome of COVID-19 during hospitalization in both the overall population and the subgroup with atherogenic dyslipidemia.

CONCLUSIONS

Atherogenic dyslipidemia detected on admission can be associated with critical in-hospital course of COVID-19. Further investigations are needed to elucidate the hypothetical role of insulin resistance and related lipid abnormalities in severe acute respiratory syndrome coronavirus 2 pathogenesis. Assessment of lipid profile should be encouraged in patients hospitalized for COVID-19.

Persistence of Anti-S Titre among Healthcare Workers Vaccinated with BNT162b2 mRNA COVID-19

The COVID-19 pandemic has led to health, social and economic consequences for public health systems. As a result, the development of safe and effective vaccines, in order to contain the infection quickly became a priority. The first vaccine approved by the Italian Agency for Drugs Authorization (AIFA) was the BNT162b2 mRNA vaccine, developed by BioNTech and Pfizer (Comirnaty). Comirnaty contains a molecule called messenger RNA (mRNA), which is a nucleoside-modified RNA that encodes the SARS-CoV-2 spike glycoprotein. Even if data from phase I suggest that vaccine induced antibodies can persist for up to six months following the second shot of BNT vaccine, data regarding the real duration of immunological protection are lacking. In this study, we aimed to evaluate the duration of serological protection by detecting the presence of anti-S-RBD (receptor-binding domain) antibodies for SARS-CoV-2 among a large group of healthcare workers (HCWs) three months after vaccination. 99% of HCWs had a detectable titre of anti-S SARS-CoV-2 antibodies 90 days after the second vaccine shot. Elderly operators showed significantly lower levels of protective antibodies when compared to the younger ones, thus they could become unprotected earlier than other operators.

Alterations in Rev-ERBα/BMAL1 ratio and glycated hemoglobin in rotating shift workers: the EuRhythDia study

OBJECTIVE

To detect premature gluco-metabolic defects among night shift workers with disturbances in circadian rhythms.

DESIGN AND METHODS

We performed a hypothesis-generating, cross-sectional analysis of anthropometric, metabolic, lipid, and inflammation parameters, comparing active (a-NSW, n = 111) and former (f-NSW, n = 98) rotating night shift workers with diurnal workers (controls, n = 69). All participants were hospital nurses. We also evaluated the Pittsburgh Sleep Quality Index (PSQI) and assessed expression of transcription factors REV-ERBα and BMAL1 in peripheral blood mononuclear cells (PBMCs), as indicators of the molecular clock.

RESULTS

Both a-NSW and f-NSW participants had significantly higher glycated hemoglobin (HbA1c) and white blood cell counts (WBC) (p < 0.001 for both), PSQI global score (p = 0.001) and diastolic blood pressure levels (p = 0.024) compared with controls. Expression of REV-ERBα/BMAL1 RNA in PBMC was significantly higher in a-NSW (p = 0.05) than in f-NSW or control participants. Multivariate regression analysis showed that working status and PSQI were independent determinants of higher HbA1c levels (p < 0.001).

CONCLUSIONS

We demonstrated that young, healthy night shift workers show subclinical abnormalities in HbA1c and changes in peripheral clock gene expression.

Lactoferrin Against SARS-CoV-2: In Vitro and In Silico Evidences

Lactoferrin (Lf) is a cationic glycoprotein synthetized by exocrine glands and is present in all human secretions. It is also secreted by neutrophils in infection and inflammation sites. This glycoprotein possesses antimicrobial activity due to its capability to chelate two ferric ions per molecule, as well as to interact with bacterial and viral anionic surface components. The cationic features of Lf bind to cells, protecting the host from bacterial and viral injuries. Its anti-inflammatory activity is mediated by the ability to enter inside the nucleus of host cells, thus inhibiting the synthesis of proinflammatory cytokine genes. In particular, Lf down-regulates the synthesis of IL-6, which is involved in iron homeostasis disorders and leads to intracellular iron overload, favoring viral replication and infection. The well-known antiviral activity of Lf has been demonstrated against DNA, RNA, and enveloped and naked viruses and, therefore, Lf could be efficient in counteracting also SARS-CoV-2 infection. For this purpose, we performed in vitro assays, proving that Lf exerts an antiviral activity against SARS-COV-2 through direct attachment to both SARS-CoV-2 and cell surface components. This activity varied according to concentration (100/500 μg/ml), multiplicity of infection (0.1/0.01), and cell type (Vero E6/Caco-2 cells). Interestingly, the in silico results strongly supported the hypothesis of a direct recognition between Lf and the spike S glycoprotein, which can thus hinder viral entry into the cells. These in vitro observations led us to speculate a potential supplementary role of Lf in the management of COVID-19 patients.

Evaluation of Immunity for Mumps among Vaccinated Medical Students

Healthcare workers are considered at higher risk for mumps infection than the general population. Since 2017, the national immunization plan recommended the administration of a dose of measles–mumps–rubella (MMR) vaccine to the healthcare operators who are unable to demonstrate a complete vaccination history or that are seronegative for at least one of the three agents. Regarding mumps infection, based on actual concerns regarding the loss of protection over the years after vaccination, the Advisory Committee on Immunization Practices (ACIP) recommended to administer a third dose of vaccine to operators previously vaccinated with two doses of MMR vaccine who belong to a group at increased risk of mumps infection in the event of an epidemic. This guideline, however, is not currently followed in Italy, resulting in a potential risk for vaccinated operators to become unprotected from mumps over the years. The aim of our study is to evaluate the persistence of a protective antibody level for mumps among medical students vaccinated during infancy or adolescence, at the start of their hospital internship. We retrospectively evaluated mumps-specific IgG levels in a group of medical students, in the period from 1 January to 31 December 2020. We evaluated the persistence of the detectable level of mumps-specific antibodies in relation to their vaccinal status, gender and time elapsed from vaccination. We found that 17.4% (65 subjects) of our sample were seronegative for mumps. The univariate analysis showed a significant difference in serological protection between male and female gender (77.0% vs. 86.2%; p < 0.05 with chi² test) and between age classes (86.5% vs. 76.4%; p < 0.05 for subjects aged 18–23 years and over 23 years, respectively). Female gender was significantly related to higher serological protection even after adjusting for age classes and number of vaccine doses administered in a multivariate analysis model. Our study shows a substantial percentage of subjects lacking a protective mumps titer among medical students who were vaccinated in childhood. Given the higher risk of infection among those subjects, routine pre-employment screening should be performed among those operators regardless of their vaccination history and a third dose of MMR should be offered to unprotected students.

High body mass index and night shift work are associated with COVID-19 in health care workers

OBJECTIVE

To assess the magnitude of COVID-19 spread and the associated risk factors among health care workers (HCWs), we conducted an in-hospital survey in a central Italian COVID Hospital.

METHODS

Participants underwent nasopharyngeal swab and/or serum collection for SARS-CoV-2 IgG examination. We divided participants according to working status, into rotating-night shift workers (r-NSW) and day-workers.

RESULTS

We found 30 cases of COVID-19 infection in a total of 1180 HCWs (2.5%). Most COVID-19-positive hospital employees were r-NSWs with significantly higher BMI than that of individuals who tested negative. After adjustment for covariates, night work and BMI > 30 were associated with a markedly greater risk of COVID-19 diagnosis (OR 3.049 [95%CI 1.260-7.380] and OR 7.15 [95%CI 2.91-17.51], respectively).

CONCLUSIONS

Our results describe a low prevalence of COVID-19 infection among HCWs at a central Italian COVID Hospital. COVID-19 infection risk appears to be associated with obesity and night shift work, thus supporting the need for careful health surveillance among frontline HCWs exposed to COVID-19.

Monthly fluctuations in 25-hydroxy-vitamin D levels in day and rotating night shift hospital workers

PURPOSE

Epidemiological studies have suggested that indoor hospital employees, either day or night shift workers, are at high risk of metabolic and cardiovascular diseases. Interestingly, previous reports have also described a higher prevalence of vitamin D (25OHD) deficiency among these workers. However, few studies have determined the monthly variations in 25OHD levels in indoor hospital employees.

METHODS

To address this lack of knowledge, in 2018, during the periodic health surveillance checks at the Service of Occupational Medicine, we measured 25OHD levels in a group of indoor hospital workers (88 rotating night shift workers vs 200 day workers). Each participant received a single annual health surveillance check.

RESULTS

The mean levels of 25OHD were consistently below the lower limit of the normal range in both groups throughout the year. Only in the summer, day workers but not rotating night shift workers (mean 25.9 ± 11.3 ng/ml vs 23.1 ± 9.1 ng/ml; p = 0.042) showed levels significantly higher than those in the other seasons. This difference remained statistically significant even after correction for study covariates [β = -  1.649 (CI - 0.283/- 3.482), p = 0.039]. A cosinor analysis confirmed that the difference in the 25OHD levels between groups was present later in the year.

CONCLUSIONS

We found that relatively young healthy hospital workers, especially those with rotating night shifts, in the absence of significant metabolic risk factors, have a high risk of 25OHD deficiency/insufficiency. Because 25OHD deficiency may lead to a progression to more severe conditions such as osteoporosis or bone fractures, our results should be verified in larger cohorts including different ancestries.

Seroprevalence for vaccine-preventable diseases among Italian healthcare workers

Healthcare workers (HCWs) have an increased risk to be exposed to infectious diseases compared to the general population. For this reason, according to the National Immunization and Prevention Plan, all HCWs should have demonstrable evidence of immunity to measles, mumps, rubella, varicella and Hepatitis B. Earlier studies have already shown that a large percentage of Italian operators lacked immune protection for one or more of those pathogens.The aim of this study was to evaluate the immunization status for vaccine-preventable diseases of HCWs in a large Italian teaching hospital. We retrospectively evaluated clinical records and serological data of HCWs who followed the occupational health surveillance program between January 1 and December 31 2019. We reviewed the clinical records of 1,017 HCWs: 393 males and 624 females with a median age of 35.69 y (range: 19-67). Protective IgG antibody values were documented in the 88.0%, 75.7%, 90.3%, 87.4% and 85.7% of the HCWs screened, respectively, against measles, mumps, rubella, varicella and Hepatitis B. Age was significantly related to serological protection against measles, mumps and varicella but was not significantly related to protective IgG levels for rubella and HBV.Female gender was significantly related to a higher protection rate against Hepatitis B (87.8 vs 82.4%; p < .01) whereas males were significantly more protected against varicella (92-4 vs 84.1%; p < .01).Our study shows suboptimal levels of protection among Italian HCWs and a consequent increased risk of infection for them and their patients. Public health policies should be focused on improving preventive strategies, including serological screening and workplace vaccination of nonimmune individuals.

Carotid intimal medial thickness in rotating night shift is related to IL1β/IL6 axis

BACKGROUND AND AIMS

Sleep disturbances may promote glucose abnormalities and inflammatory burden among shift workers. Therefore, precocious subclinical atherosclerotic process might develop in healthy shift workers even without known metabolic and cardiovascular risk factors.

METHODS AND RESULTS

We measured anthropometric parameters, glucose, lipids, inflammation and common carotid Intimal Medial Thickness (cIMT) in rotating-night shift workers (r-NSW, n = 88, age = 40.3 ± 7.8 y) in comparison with former-night shift workers (f-NSW, n = 35, age = 44.2 ± 6.4 y) and with day-only workers (DW, n = 64, age = 44.1 ± 8.9 y). R-NSW and f-NSW showed significantly higher cIMT and high sensitivity C-Reactive Protein (hs-CRP) respect to DW (p = 0.043 and p = 0.025, respectively). IL-1β levels were higher in r-NSW than in DW and f-NSW (p = 0.043) and significantly correlated with IL6 (r = 0.365, p < 0.001). In addition, r-NSW and f-NSW had higher HbA1c levels in comparison with DW (p = 0.047). Carotid-IMT was significantly related to night shift work (p = 0.023), with age (p < 0.001), with HOMA IR (p = 0.009), with insulin (p = 0.006) with HbA1c (p = 0.002), with LDL cholesterol (p < 0.001), with diastolic BP (p < 0.001), with WBC (p = 0.002) and with IL6 (p = 0.004). After performing a multivariate analysis night shift work remained statistically related to cIMT (B = 2.633, 95%CI = 0.489-4.776, p = 0.016).

CONCLUSIONS

Our result described a possible link bridging night shift work, inflammation and carotid Intimal Medial Thickness. Future studies are warranted to understand if carotid atherosclerosis process should be mainly driven by the IL1β/IL6 citokine axis connected to sleep disturbances.

Subjective neurological symptoms frequently occur in patients with SARS-CoV2 infection

OBJECTIVE

Coronavirus disease 2019 (COVID-19) represents a novel pneumonia leading to severe acute respiratory syndrome (SARS). Recent studies documented that SARS-Coronavirus2 (SARS-CoV2), responsible for COVID-19, can affect the nervous system. The aim of the present observational study was to prospectively assess subjective neurological symptoms (sNS) in patients with SARS-CoV2 infection.

METHODS

We included patients hospitalized at the University Hospital of Rome "Tor Vergata", medical center dedicated to the treatment of patients with COVID-19 diagnosis, who underwent an anamnestic interview about sNS consisting of 13 items, each related to a specific symptom, requiring a dichotomized answer.

RESULTS

We included 103 patients with SARS-CoV2 infection. Ninety-four patients (91.3%) reported at least one sNS. Sleep impairment was the most frequent symptom, followed by dysgeusia, headache, hyposmia, and depression. Women more frequently complained hyposmia, dysgeusia, dizziness, numbeness/paresthesias, daytime sleepiness, and muscle ache. Moreover, muscle ache and daytime sleepiness were more frequent in the first 2 days after admission. Conversely, sleep impairment was more frequent in patients with more than 7 days of hospitalization. In these patients we also documented higher white blood cells and lower C-reactive protein levels. These laboratory findings correlated with the occurrence of hyposmia, dysgeusia, headache, daytime sleepiness, and depression.

CONCLUSIONS

Patients with SARS-CoV2 infection frequently present with sNS. These symptoms are present from the early phases of the disease. The possibly intrinsic neurotropic properties of SARS-CoV2 may justify the very high frequency of sNS. Further studies targeted at investigating the consequences of SARS-CoV2 infection on the CNS should be planned.

Lipid composition modulates ATP hydrolysis and calcium phosphate mineral propagation by TNAP-harboring proteoliposomes

Bone biomineralization is mediated by a special class of extracellular vesicles, named matrix vesicles (MVs), released by osteogenic cells. The MV membrane is enriched in sphingomyelin (SM), cholesterol (Chol) and tissue non-specific alkaline phosphatase (TNAP) compared with the parent cells' plasma membrane. TNAP is an ATP phosphohydrolase bound to cell and MV membranes via a glycosylphosphatidylinositol (GPI) anchor. Previous studies have shown that the lipid microenvironment influences the catalytic activity of enzymes incorporated into lipid bilayers. However, there is a lack of information about how the lipid microenvironment controls the ability of MV membrane-bound enzymes to induce mineral precipitation. Herein, we used TNAP-harboring proteoliposomes made of either pure dimyristoylphosphatidylcholine (DMPC) or DMPC mixed with either Chol, SM or both of them as MV biomimetic systems to evaluate how the composition modulates the lipid microenvironment and, in turn, TNAP incorporation into the lipid bilayer by means of calorimetry. These results were correlated with the proteoliposomes' catalytic activity and ability to induce the precipitation of amorphous calcium phosphate (ACP) in vitro. DMPC:SM proteoliposomes displayed the highest efficiency of mineral propagation, apparent affinity for ATP and substrate hydrolysis efficiency, which correlated with their highest degree of membrane organization (highest ΔH), among the tested proteoliposomes. Results obtained from turbidimetry and Fourier transformed infrared (FTIR) spectroscopy showed that the tested proteoliposomes induced ACP precipitation with the order DMPC:SM>DMPC:Chol:SM≈DMPC:Chol>DMPC which correlated with the lipid organization and the presence of SM in the proteoliposome membrane. Our study arises important insights regarding the physical properties and role of lipid organization in MV-mediated mineralization.

Managing the risk of bacterial meningitis among healthcare workers

BACKGROUND

Meningococcal disease is generally caused by A, B, C, W and Y subgroups of Neisseria meningitidis. In 2015, the Italian mass media focused on this disease due to the death of two nurses. This generated alarm in the general population, especially in healthcare workers (HCWs). The Occupational Medicine department of the Foundation PTV Polyclinic Tor Vergata (PTV) offered free MenACWY vaccine to HCWs and to students of the University of Rome Tor Vergata.

AIMS

To analyse the prevalence of N. meningitidis in PTV, a large teaching hospital, and to evaluate preventive measures offered to individuals at risk (i.e. HCWs and students).

METHODS

The Hospital Informatic Service provided data about patients admitted to PTV from January 2012 to December 2016. Hospital Discharge Registers were analysed and all cases of meningitis were selected. MenACWY vaccine administered to HCWs and students of PTV in 2017 was analysed.

RESULTS

There was just one case of meningococcal disease in 2016. Of the 117 MenACWY vaccines administered, 42% were given to students, 32% to doctors, 8% to nurses, 2% to clerks and 16% to other healthcare professionals.

CONCLUSIONS

International guidelines recommend MenACWY vaccine for microbiologists exposed to N. meningitidis isolates. The Italian Legislative Decree 81/2008, however, states that occupational physicians can adopt special protective measures such as vaccination programmes for HCWs. The response rate highlights how perceived risk may influence behaviour even in populations with a higher background knowledge than the general population.

Measles immunity in an Italian teaching hospital

BACKGROUND

Healthcare workers (HCWs) have an increased exposure risk to measles, which can put them, their patients and their relatives at risk of infection. In Italy, 4617 cases of measles were reported in 2017; 302 involving HCWs. According to the Italian National Immunization and Prevention Plan, all HCWs should have demonstrable evidence of immunity to measles.

AIMS

To evaluate measles immunization status in HCWs at a large Italian teaching hospital.

METHODS

We analysed clinical records and measles-specific IgG antibody titres of HCWs undergoing occupational health surveillance between 1 January and 31 August 2017.

RESULTS

Among the 1532 HCWs (mean age 32.7 ± 10.4 years) included in the study, 87% (1328) had protective antibody titres. The proportion of protective titres was highest in those born before 1982. No significant gender differences in mean measles-specific IgG antibody titres were detected.

CONCLUSIONS

Our study shows non-protective measles IgG antibody titres in a substantial percentage of HCWs, especially those born in the 1980s and 1990s. Due to the increased risk of measles transmission in the hospital environment, increased prevention strategies are required, including rigorous screening and prompt vaccination of non-immune workers.

Cost-effectiveness of workplace vaccination against measles

Measles is one of the most contagious infectious diseases. Measles vaccine, which has been introduced in Italy in 1979, is highly effective in preventing the disease (two-dose vaccine effectiveness is 99%). In 2017, Italy was the second country of EU for number of cases of measles. A study conducted in the same year showed that 22.3% of measles infection happened in hospital settings and 6.6% of cases occurred in HCWs. This risk group showed low rates of adhesion to the vaccination campaign. For this reason, we hypothesized that workplace vaccination could lead to better vaccination rates in HCWs. Moreover, we focused the vaccination campaign on a specific target group composed of HCWs not serologically immune and previously not vaccinated. We analyzed the clinical records of measles-specific IgG antibodies of 2,940 HCWs, that underwent occupational health surveillance between 1 January 2017 and 31 December 2017. 15.3% (450) was seronegative for measles, especially in the age group under 35 years. We compared the costs related to strategies with and without serological screening. Our study confirmed that immunization strategy with pre-vaccination screening was cost-effective compared to the vaccination without screening. In our sample, in fact, administration of two dose vaccine only susceptible HCWs determine a saving of 146,262 €. The vaccination of HCWs remains a topical issue in preventing the transmission of infectious disease in the hospital setting. Due to the cost-effectiveness evaluation, we recommend extending the pre-vaccination screening to identify the real susceptible workers.

Prevalence and Risk Factors for Latent Tuberculosis Infection among Healthcare Workers in a Low Incidence Country

Background:

Tuberculosis prevention is a major goal in the hospital setting. Because of the possible progression or reactivation of latent disease, the screening of healthcare workers is an important issue in the TB control program. The aim of the study was to assess the prevalence of LTBI (latent tuberculosis infection) and to evaluate the main risk factors related to this condition in a teaching hospital in Italy.

Methods:

We reviewed the data of a tuberculosis screening conducted on 3622 healthcare professionals in a teaching hospital in Rome. All subjects were evaluated by QuantiFERON test which if positive, was followed by appropriate clinical and diagnostic procedures.

Results:

Latent Tuberculosis Infection LTBI condition was detected in 2.1% of the cases, most commonly in men. Male gender, higher age class, country of birth and nurse job were statistically related with the positivity to QuantiFERON test.

Conclusion:

LTBI was relatively uncommon in our population, however, given the potential risk of reactivation and progression to overt disease, the screening of healthcare workers and students is recommended in the hospital of low-incidence countries.

Persistence of Immunity for Hepatitis B Virus among Heathcare Workers and Italian Medical Students 20 Years after Vaccination

Background: Immunization of healthcare workers (HCWs) and medical students for the hepatitis B virus (HBV) is a crucial part of the hospital infection control programs. The aim of our study was to evaluate the persistence of anti-HBV specific antibodies in HCWs vaccinated during infancy or adolescence. Methods: Medical records of 734 consecutive subjects born after 1980 (481 females, 65.5% and 253 males, 34.5%) who underwent serological testing for anti-hepatitis B surface antibodies (anti-HBs) were evaluated. Results: A non-protective titer (<10 mUI) was found in 88/734 (12.0%) subjects; 84 (47.8%) of them received a booster dose of anti-hepatitis B vaccine and the anti-HBs titer of 58 subjects was measured 1 month after administration. A protective titer (anti-HBs >10 mIU/mL) was observed in almost 90% of subjects receiving the booster dose. Conclusions: A substantial percentage of HCWs had a non-protective anti-HBs titer at the time of the first employment, especially those vaccinated at birth age. However, the response to the booster dose showed that in these subjects, an anti-HBs titer <10 mIU/mL was due to the physiological decline of antibodies over the years. Therefore, primary immunization in childhood is highly effective and provides lasting immunity against HBV infection.

Quantitative atomic force microscopy provides new insight into matrix vesicle mineralization

Matrix vesicles (MVs) are a class of extracellular vesicles that initiate mineralization in cartilage, bone, and other vertebrate tissues by accumulating calcium ions (Ca²⁺) and inorganic phosphate (P_i) within their lumen and forming a nucleation core (NC). After further sequestration of Ca²⁺ and P_i, the NC transforms into crystalline complexes. Direct evidence of the existence of the NC and its maturation have been provided solely by analyses of dried samples. We isolated MVs from chicken embryo cartilage and used atomic force microscopy peak force quantitative nanomechanical property mapping (AFM-PFQNM) to measure the nanomechanical and morphological properties of individual MVs under both mineralizing (+Ca²⁺) and non-mineralizing (-Ca²⁺) fluid conditions. The elastic modulus of MVs significantly increased by 4-fold after incubation in mineralization buffer. From AFM mapping data, we inferred the morphological changes of MVs as mineralization progresses: prior to mineralization, a punctate feature, the NC, is present within MVs and this feature grows and stiffens during mineralization until it occupies most of the MV lumen. Dynamic light scattering showed a significant increase in hydrodynamic diameter and no change in the zeta potential of hydrated MVs after incubation with Ca²⁺. This validates that crystalline complexes, which are strongly negative relative to MVs, were forming within the lumen of MVs. These data were substantiated by transmission electron microscopy energy dispersive X-ray and Fourier transform infrared spectroscopic analyses of dried MVs, which provide evidence that the complexes increased in size, crystallinity, and Ca/P ratio within MVs during the mineralization process.

Pre-vaccination IgG screening for mumps is the most cost-effectiveness immunization strategy among Health Care Workers

Health Care Workers (HCWs) have an increased risk of contracting contagious disease, including mumps. In January 2017 the Italian National Vaccine Prevention Plan 2017-2019, recommended the administration of a dose of MMR vaccine (Measles-Mumps-Rubella) to the Health Care Workers (HCWs) that, working in a risky environment, did not carry out the complete vaccination cycle of MMR or that are seronegative for at least one of the three vaccine viruses. In October of the same year, the Advisory Committee on Immunization Practices (ACIP) recommended a third dose of a vaccine containing Mumps Virus for people previously vaccinated with 2 doses, belonging to a group or to a population at increased risk of acquire mumps in the event of an epidemic. We analyzed the clinical records and values of mumps-specific IgG antibodies of 3032 HCWs (mean age 32.80 ± 10.75 years), that underwent occupational health surveillance between January 1st 2017 and March 31th 2018. The HCWs were also screened for measles, rubella, mumps using serological methods. 13% (405) was seronegative for mumps, especially among HCWs between 18 and 36 years. We calculated the cost-effectiveness of two-doses and three-doses MMR vaccination. The cost of vaccination without screening was significantly more expensive (cost difference: 99 712 € and 184 996 €) both in case of two-dose and three-dose MMR vaccination respectively. Our study suggests that, in HCWs, the assessment of the mumps antibody titer before vaccination may be a useful complement to vaccination itself, because it is more accurate and cost-effective than direct immunization of unvaccinated subjects.

Severe facial reaction to thiurams in surgeons

Contact dermatitis is a major problem in the healthcare environment and in other sectors. Healthcare professionals may be exposed to a large number of chemical agents, including the accelerators for rubber vulcanization process. The prevalence of allergic contact dermatitis among operators in the sector ranges 13–30%. This paper describes the case of a 46-year-old male cardiac surgeon affected by a severe skin reaction localized on the face in the absence of hand dermatitis, presumably resulting from the use of a surgical patch applied to the face. Patch tests were performed and the result was negative for latex and positive (+++) for thiuram mix. A thiuram-free tape was prescribed and the operator’s dermatitis improved significantly. Thus, it would be very important to pay attention to skin disorders in health workers and thiuram as an occupational allergen. Med Pr. 2019;70(1):121–4

Diabetes and work: The need of a close collaboration between diabetologist and occupational physician

AIM

The Italian Society of Occupational Medicine (SIML), the Italian Diabetes Society (SID) and the Association of Diabetologists (AMD) joined a working group that produced a consensus paper aimed to assess the available evidence regarding the interplay between specific working conditions, including shift- and night-time work, working activities at high risk of accidents and work at heights, working tasks requiring high-energy expenditure, working activities at extreme temperatures and diabetes.

DATA SYNTHESIS

Diabetes is a group of metabolic disorders caused by defects in insulin secretion and/or action affecting millions of people worldwide, many of whom are or wish to be active members of the workforce. Although diabetes, generally, does not prevent a person from properly performing his/her working tasks, disease complications can significantly compromise a person's ability to work. Therefore, it appears evident the need to understand the relationship between occupational risk factors and diabetes. The working group included in the document some practical recommendations useful to ensure diabetic workers the possibility to safely and effectively undertake their jobs and to adequately manage and treat their disease, also in the workplace. In this perspective concerted action of all the workplace preventive figures, occupational physicians and diabetologists should be strongly encouraged.

CONCLUSIONS

Further studies are necessary to define workplace-based interventions, which should be minimally invasive towards the work organization, allowing diabetic workers to fully realize their work skills while improving their wellbeing at work.

Nasal cytology as a screening tool in formaldehyde-exposed workers

Background

Workers in pathology and anatomy laboratories may be exposed to formaldehyde. An evaluation of the early effects of this substance is, therefore, paramount. This preliminary study was conducted to evaluate if nasal cytology could be used as a tool to detect changes in nasal mucosa in workers exposed to formaldehyde.

Aims

To assess whether nasal cytology was able to reveal any alteration of nasal mucosa in workers exposed to formaldehyde compared to unexposed subjects, and to ascertain whether a specific pattern of alterations correlated with years of exposure in order to evaluate long-term occupational exposure effects.

Methods

The study included a group of workers exposed to formaldehyde and a group of non-exposed workers. All subjects underwent clinical examination, followed by nasal cytology. Pathological indices from each rhinocytograms were compared between the two groups.

Results

Nasal cytology revealed a chronic inflammatory non-allergic condition in the exposed group. Qualitative analysis of data distribution of neutrophils and mucous-secreting/ciliated cells ratio showed data clustering with a cut-off set at 15 years of exposure. The mean formaldehyde concentrations ranged from <0.04 to 0.15 parts per million (ppm). The maximum levels of formaldehyde concentrations ranged from 0.2 to 0.67 ppm.

Conclusions

Our data indicate that nasal cytology may be a promising tool for the health surveillance of workers exposed to formaldehyde and may also represent a useful research tool for the study of the health effects of other chemicals irritants for the upper airways.

Is there a relationship between stature and age of onset of type 2 Diabetes?

AIMS

MSP1A and MSP1B polymorphic sites located in the GH genomic area have been found associated with GH response to insulin stimulation, with familiar short stature and with age at onset of Type 2 Diabetes (T2D). These observations prompted us to search for a possible relationship between stature and age at onset of the disease.

METHODS

We have reexamined the data of 272 subjects with T2D mellitus.

RESULTS

There is a highly significant negative correlation between stature and age at onset in non obese females (p < 0.001) but not in obese females and in males. In non obese females with stature within the first quartile the mean age at onset is 62 years while in those with a stature greater than the first quartlile the mean age at onset is 52 yesrs (p < 0.001). No difference is observed in obese females and males.

CONCLUSIONS

These observations suggest the existence of different mechanisms underlying susceptibility to T2D. In addition to the well known increased risk due to obesity, endocrine dysfunctions related to genetic variability within the GH genomic area could represent another mechanism operating in non obese females. A cluster of non obese women characterized by short stature and late onset of diabetes seems to be separated by this mechanism from other women.

Risk of radiation-induced lens opacities among surgeons and interventional medical staff

The main effect of ionizing radiation on the eyes is the onset of posterior cortical and subcapsular cataracts. Recent studies have raised questions about the mechanism of ocular damage and the threshold dose for the onset of such effects. Currently, operators may be exposed to ionizing radiation during surgical procedures. It has been estimated that urologists can be exposed to an annual dose close to or above 20 mSv/year. The aim of our study was to evaluate the frequency of cataracts in a group of professional radiological operators to verify their possible association with the radiation dose to the crystalline lens and the tasks performed. The records of 73 health workers exposed to ionizing radiation were reviewed. The average annual dose to the crystalline lens, the number of years of exposure, and the presence of radiation-compatible opacities were assessed for all operators. Lenticular opacities were observed in 16.4% of subjects. The presence of alterations was associated with exposure doses below 10 mSv and > 10 years' experience in fluoroscopically guided procedures. Based on our results, protection of the crystalline lens against exposure to ionizing radiation by means of goggles is recommended. In addition, examination of the lens via slit lamp examination is recommended for all operators involved in interventional procedures with the current levels of radiation exposure.