One characteristic feature of acute 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxicity is dramatic interspecies and interstrain variability in sensitivity. This complicates dioxin risk assessment for humans. However, this variability also provides a means of characterizing mechanisms of dioxin toxicity. Long-Evans (Turku/AB) rats are orders of magnitude more susceptible to TCDD lethality than Han/Wistar (Kuopio) rats, and this difference constitutes a very useful model for identifying mechanisms of dioxin toxicity. We adopted a proteomic approach to identify the differential effects of TCDD exposure on liver protein expression in Han/Wistar rats as compared with Long-Evans rats. This allows determination of which, if any, protein markers are indicative of differences in dioxin susceptibility and/or responsible for conferring resistance. Differential protein expression in total liver protein was assessed using two-dimensional gel electrophoresis, computerized gel image analysis, in-gel digestion, and mass spectrometry. We observed significant changes in the abundance of several proteins, which fall into three general classes: (i) TCDD-independent and exclusively strain-specific (e.g. isoforms of the protein-disulfide isomerase A3, regucalcin, and agmatine ureohydrolase); (ii) strain-independent and only dependent on TCDD exposure (e.g. aldehyde dehydrogenase 3A1 and rat selenium-binding protein 2); (iii) dependent on both TCDD exposure and strain (e.g. oxidative stress-related proteins, apoptosis-inducing factor, and MAWD-binding protein). By integrating transcriptomic (microarray) data and genomic data (computational search of regulatory elements), we found that protein expression levels were mainly controlled at the level of transcription. These results reveal, for the first time, a subset of hepatic proteins that are differentially regulated in response to TCDD in a strain-specific manner. Some of these differential responses may play a role in establishing the major differences in TCDD response between these two strains of rats. As such, our work is expected to lead to new insights into the mechanism of TCDD toxicity and resistance. Molecular & Cellular Proteomics 5:882-894, 2006.

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Developmental exposure to polychlorinated biphenyls (PCBs) has been associated with cognitive deficits in humans and laboratory animals by mechanisms that remain unknown. Recently, it has been shown that developmental exposure to 2,2',3,4,4',5'-hexachlorobiphenyl (PCB138), a food-relevant PCB congener, decreases the learning ability of young rats. The aim of this study was to characterize the effect of perinatal exposure to PCB138 on the brain proteome profile in young rats in order to gain insight into the mechanisms underlying PCB138 neurotoxicity. Comparison of the cerebellum proteome from 3-month-old unexposed and PCB138-exposed male offspring was performed using state-of-the-art label-free semiquantitative mass spectrometry method. Biological pathways associated with Ca(2+) homeostasis and androgen receptor signaling pathways were primarily disrupted. These perturbations may contribute toward a premature ageing-like proteome profile of the cerebellum that is triggered by PCB138 exposure in males. Our proteomic data provide insights into the phenomena that may be contributing to the PCB138 neurotoxicity effects observed in laboratory rodents and correlate with PCB exposure and decreased cognitive functions in humans. As such, this study highlights the importance of PCB138 as a risk factor in developmental neurotoxicity in laboratory rodents and humans.

Background: The aromatic amine 4-aminobiphenyl (4-ABP) is an environmental and occupational contaminant known to be a major etiological agent of human bladder cancer. 4-ABP metabolites are able to form DNA adducts that may induce mutations and initiate bladder carcinogenesis. Cells exposed to 4-ABP may develop resistance to the carcinogen. The aim of the present study was to detect and identify proteins whose expression is altered in the bladder carcinoma RT112 sub-lines selected for acquired resistance to 4-ABP, in order to disentangle the mechanisms.

Objectives Systemic sclerosis (SSc) patients are at risk for a severe disease course during SARS-CoV-2 infection either due to comorbidities or immunosuppression. The availability of SARS-CoV-2 vaccines is crucial for the prevention of this hard-to-treat illness. The aim of this study is to assess the humoral response after mRNA vaccination against SARS-CoV-2 in SSc patients. Method Seropositivity rate and serum IgG levels were evaluated 1 month (t1) and 3 months (t3) after the second dose of vaccine in a cohort of SSc patients and healthy controls (HC). Differences were made with Student’s or Mann–Whitney’s t-test and with the chi-square or Fisher exact test. Logistic regression model including immunosuppressive treatments (corticosteroids, CCS; mycophenolate mofetil, MMF; methotrexate, MTX; rituximab, RTX) was built to assess the predictivity for seropositivity. Results The seropositivity rate was similar in 78 SSc patients compared to 35 HC at t1 but lower at t3. SSc patients had lower serum IgG levels than HC at t1 but not at t3. SSc patients treated with immunosuppressive therapy showed both a lower seropositive rate (t1, 90.3% vs 100%; t3, 87.1% vs 97.9%; p < 0.05) and serum IgG levels than untreated patients both at t1 [851 BAU/ml (IQR 294–1950) vs 1930 BAU/ml (IQR 1420–3020); p < 0.001] and t3 [266 BAU/ml (IQR 91.7–597) vs 706 BAU/ml (IQR 455–1330); p < 0.001]. In logistic regression analysis, only MTX was significant [OR 39.912 (95% CI 1.772–898.728); p < 0.05]. Conclusions SSc patients treated with MTX had a lower serological response to mRNA vaccine, and even low doses of CCS can adversely affect antibody titer and vaccination response. Key Points• SSc patients are able to produce vaccine-induced antibodies after mRNA vaccination.• In SSc patients, clinical characteristics of disease did not influence seropositivity rate.• In SSc patients, even low doses of CCS can adversely affect antibody titer and vaccination response.• In SSc patients, MTX treatment is mainly associated with reduced seropositivity and lower serum IgG levels.

This study aims to investigate whether HCWs infected with COVID-19 may experience potential psychological consequences and a higher incidence of depression, anxiety, work-related stress, and burnout compared to non-infected HCWs. A case–control study with 774 participants was conducted comparing COVID-19-infected HCWs (cases) and non-infected HCWs (controls) from the Occupational Medicine Unit at the Teaching Hospital Policlinico Umberto I, who were administered the same questionnaire including Hospital Anxiety and Depression Scale, Copenhagen Burnout Inventory and Karasek’s Job Content Questionnaire. No differences in the levels of burnout and decision latitude were found between the two groups. Cases showed higher level of anxiety and job demand compared to controls. In contrast, levels of depression in the case group were significantly lower compared to the control group. The results are indicating the need for workplace health promotion activities based on stress and burnout management and prevention. Multiple organizational and work-related interventions can lower the impact of mental health-related issues in the COVID-19 pandemics, including the improvement of workplace infrastructures, as well as the adoption of correct and shared anti-contagion measures, which must include regular personal protective equipment supply, and the adoption of training programs that deal with mental health-related issues.

Objective: To evaluate the safety and immunogenicity of the Pfizer-BioNTech COVID-19 vaccine in gynecologic oncology patients under chemotherapy. Methods: A prospective cohort study including gynecologic oncology women who were under chemotherapy or had completed it within 6 months at the time of the study. All patients received a two-dose schedule of the Pfizer-BioNTech COVID-19 vaccine. Results were compared with a control group of healthy women vaccinated in the same period. Results: Overall, 44 oncologic patients with a mean age of 61.3 ± 10.7 years were enrolled: 28 (63.6%) had ovarian cancer, 9 (20.4%) endometrial, and 7 (16%) cervical. The IgG antibody titer after 1 month from vaccination was low in 9 (20.5%) patients, moderate in 21 (47.7%), and high in 14 (31.8%). The 3-month titer was null in 2 (4.5%) patients, low in 26 (59.1%), moderate in 13 (29.5%), and high in 3 (6.8%). Patients ≥ 50 years reported lower 1-month (p = 0.018) and 3-month (p = 0.004) titers compared with <50 years. Patients with BMI < 30 kg/m2 had a higher 1-month titer compared with BMI ≥ 30 kg/m2 (p = 0.016). Compared with healthy women (n = 44), oncologic patients showed a lower 3-month titer (p < 0.001). None of the patients experienced serious adverse effects. Conclusions: The COVID-19 vaccine was safe and immunogenic in gynecologic oncology patients under chemotherapy. Serological monitoring and further vaccine shots should be considered to boost protection.

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