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2.
BMJ Glob Health ; 9(4)2024 Apr 18.
Article En | MEDLINE | ID: mdl-38637119

INTRODUCTION: To examine the impact of the COVID-19 pandemic on mortality, we estimated excess all-cause mortality in 24 countries for 2020 and 2021, overall and stratified by sex and age. METHODS: Total, age-specific and sex-specific weekly all-cause mortality was collected for 2015-2021 and excess mortality for 2020 and 2021 was calculated by comparing weekly 2020 and 2021 age-standardised mortality rates against expected mortality, estimated based on historical data (2015-2019), accounting for seasonality, and long-term and short-term trends. Age-specific weekly excess mortality was similarly calculated using crude mortality rates. The association of country and pandemic-related variables with excess mortality was investigated using simple and multilevel regression models. RESULTS: Excess cumulative mortality for both 2020 and 2021 was found in Austria, Brazil, Belgium, Cyprus, England and Wales, Estonia, France, Georgia, Greece, Israel, Italy, Kazakhstan, Mauritius, Northern Ireland, Norway, Peru, Poland, Slovenia, Spain, Sweden, Ukraine, and the USA. Australia and Denmark experienced excess mortality only in 2021. Mauritius demonstrated a statistically significant decrease in all-cause mortality during both years. Weekly incidence of COVID-19 was significantly positively associated with excess mortality for both years, but the positive association was attenuated in 2021 as percentage of the population fully vaccinated increased. Stringency index of control measures was positively and negatively associated with excess mortality in 2020 and 2021, respectively. CONCLUSION: This study provides evidence of substantial excess mortality in most countries investigated during the first 2 years of the pandemic and suggests that COVID-19 incidence, stringency of control measures and vaccination rates interacted in determining the magnitude of excess mortality.


COVID-19 , Female , Male , Humans , Pandemics , Italy , Greece , Age Factors
3.
Euro Surveill ; 29(15)2024 Apr.
Article En | MEDLINE | ID: mdl-38606570

Since the end of November 2023, the European Mortality Monitoring Network (EuroMOMO) has observed excess mortality in Europe. During weeks 48 2023-6 2024, preliminary results show a substantially increased rate of 95.3 (95% CI:  91.7-98.9) excess all-cause deaths per 100,000 person-years for all ages. This excess mortality is seen in adults aged 45 years and older, and coincides with widespread presence of COVID-19, influenza and respiratory syncytial virus (RSV) observed in many European countries during the 2023/24 winter season.


COVID-19 , Influenza, Human , Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus, Human , Adult , Humans , Influenza, Human/epidemiology , Europe/epidemiology , Seasons , Respiratory Syncytial Virus Infections/epidemiology
4.
Front Psychiatry ; 14: 1228539, 2023.
Article En | MEDLINE | ID: mdl-38025465

Introduction: Numerous studies reveal that mental health-related stigma, stereotypes, and prejudices negatively affect the patients, jeopardizing their health, prognosis, and social opportunities. Healthcare professionals, who are in the first line of combating mental disease, are expected to play a significant role in drastically changing discriminatory and stigmatizing attitudes toward psychiatric patients and in diminishing the existing healthcare and social disparities. In this study, we aimed to explore and highlight the views of Greek medical students-that is of the future physicians-toward mental illness and people suffering from it. Materials and methods: It is a cross-sectional, observational study, in which 324 undergraduate students from the most populous Greek medical school of the Aristotle University of Thessaloniki, participated online, during the spring semester of 2022. The tools used were the Opinions about Mental Illness Scale (OMI) that assesses one's viewpoints about mental illness, the Social Distance Scale (SDS) that captures the desired degree of social distancing from patients with mental disorders, and the Level of Contact Report (LCR-12) that estimates the level of familiarity with them. Results: Participants displayed rather positive attitudes regarding the etiology of mental illness, social integration, and discrimination toward psychiatric patients [as evaluated with the respective OMI subscales; Etiology mean score (µ):8.87 ± 4.68, Social Integration (µ):17.79 ± 5.42, Social Discrimination (µ):13.54 ± 11.17], and more clearly favorable opinions concerning the need for social provision or the enactment of restrictive measures [as expressed with the relative OMI subscales; Social Care (µ):22.74 ± 4.56, Social Restriction (µ):13.27 ± 8.98], while claiming to be quite familiar with mental disorders and individuals experiencing them (as assessed with LCR; µ: 8.71 ± 2.16), and relatively willing to interact with them (as measured with SDS; µ:8.95 ± 4.23). Degree of familiarity with mental illness was directly proportional to the desire for contact with patients living with it, while the higher both were, the more improved most of the aforementioned OMI sectors were found to be. Female sex, clinical medical education, previous clinical psychiatric training, and living with or being a person with a mental disorder were the factors that defined a statistically refined profile in many of the aspects above. Conclusion: Our findings are in accordance with many prior and recent studies, while showing improved opinions compared to those of previous research in Greek student and healthcare population. They are calling for vigilance, rather than complacency, as well as educational and social interventions, in order to enable current and future healthcare professionals to perform their function to its fullest extent. Implications of our results and further research suggestions are included.

5.
Acta Crystallogr D Struct Biol ; 79(Pt 5): 374-386, 2023 May 01.
Article En | MEDLINE | ID: mdl-37039669

The polymorphism of human insulin upon pH variation was characterized via X-ray powder diffraction, employing a crystallization protocol previously established for co-crystallization with phenolic derivatives. Two distinct rhombohedral (R3) polymorphs and one cubic (I213) polymorph were identified with increasing pH, corresponding to the T6, T3R3f and T2 conformations of insulin, respectively. The structure of the cubic T2 polymorph was determined via multi-profile stereochemically restrained Rietveld refinement at 2.7 Šresolution. This constitutes the first cubic insulin structure to be determined from crystals grown in the presence of zinc ions, although no zinc binding was observed. The differences of the polycrystalline variant from other cubic insulin structures, as well as the nature of the pH-driven phase transitions, are discussed in detail.


Insulin, Regular, Human , Insulin , Humans , Insulin/chemistry , X-Ray Diffraction , Phenols , Crystallization
6.
Vaccine ; 41(18): 2941-2946, 2023 05 02.
Article En | MEDLINE | ID: mdl-37012116

BACKGROUND: It has been claimed that COVID-19 vaccination is associated with excess mortality during the COVID-19 pandemic, a claim that contributes to vaccine hesitancy. We examined whether all-cause mortality has actually increased in Cyprus during the first two pandemic years, and whether any increases are associated with vaccination rates. METHODS: We calculated weekly excess mortality for Cyprus between January 2020 and June 2022, overall and by age group, using both a Distributed Lag Nonlinear Model (DLNM) adjusted for mean daily temperature, and the EuroMOMO algorithm. Excess deaths were regressed on the weekly number of confirmed COVID-19 deaths and on weekly first-dose vaccinations, also using a DLNM to explore the lag-response dimension. RESULTS: 552 excess deaths were observed in Cyprus during the study period (95% CI: 508-597) as opposed to 1306 confirmed COVID-19 deaths. No association between excess deaths and vaccination rates was found overall and for any age group except 18-49 years, among whom 1.09 excess deaths (95% CI: 0.27-1.91) per 10,000 vaccinations were estimated during the first 8 weeks post-vaccination. However, detailed cause-of-death examination identified just two such deaths potentially linked to vaccination, therefore this association is spurious and attributable to random error. CONCLUSIONS: Excess mortality was moderately increased in Cyprus during the COVID-19 pandemic, primarily as a result of laboratory-confirmed COVID-19 deaths. No relationship was found between vaccination rates and all-cause mortality, demonstrating the excellent safety profile of COVID-19 vaccines.


COVID-19 , Humans , Adolescent , Young Adult , Adult , Middle Aged , COVID-19/epidemiology , COVID-19/prevention & control , Pandemics/prevention & control , COVID-19 Vaccines/adverse effects , Cyprus/epidemiology , Vaccination , Mortality
7.
J Occup Med Toxicol ; 17(1): 25, 2022 Dec 21.
Article En | MEDLINE | ID: mdl-36544155

BACKGROUND: Snake envenomation is a major neglected tropical disease, lacking data in many countries including Cyprus, a Mediterranean island inhabited by the medically important blunt-nosed viper (Macrovipera lebetina). Reviewing the 2013-2019 period, we present first-time epidemiological snakebite data in the Republic of Cyprus. METHODS: We obtained data on snake envenomation-related hospital admissions from the Ministry of Health, and population and rainfall data from the Statistical Service of Cyprus and Department of Meteorology websites. Human-viper conflict information was acquired from interviews with 12 representatives of Cypriot institutions. RESULTS: Between 2013 and 2019, 288 snake envenomation cases were admitted to public hospitals, averaging 41 people annually. The minimum was 29 cases (2017) and the maximum was 58 (2015). Snake envenomation incidence increased from 4.55 per 100,000 population (2013) to 6.84 (2015), but remained low since 2017 (3.49 in 2019). Between 2000 and 2018, the deaths of one man (73 years), and indirectly, one woman (77 years), were related to snake envenomation. While 266 cases (92%) happened between April and October (the blunt-nosed viper activity period), most envenomations occurred in September (cumulative for 2013-2019), with 88 cases (31%). Snakebite incidence peaked in the 60-69 years age group (9.19 per 100,000 population), and was higher in males (6.85) than in females (2.82). Of all admitted patients, 242 (84%) were discharged within 4 days. Mean hospital stay duration was 2.65 days, with one case of 13 days. Most patients were admitted to the general hospitals in Paphos (51%), Limassol (30%) and Nicosia (11%), which provide secondary healthcare, with the last one providing tertiary healthcare. CONCLUSIONS: Snakebite-related deaths are very rare in the Republic of Cyprus. Most envenomation cases happened in late summer (September). Short hospital stays indicate mostly non-severe clinical courses. The hospital admission data suggest that snake envenomation risk is highest in Paphos district. The statistical data hint at males and middle- to older-aged people being at highest risk, whereas from our interview data we assume that outdoor workers are at higher risk than other occupational groups.

8.
Front Psychiatry ; 13: 1027304, 2022.
Article En | MEDLINE | ID: mdl-36532175

Introduction: Research shows that mental health-related stigma, stereotypes, and prejudices have a negative impact on the patients themselves as well as on their families and social entourage. Healthcare professionals, whose expertise and professional ethos are historically acknowledged by public opinion, are expected to play a major role in combating discrimination against psychiatric patients. In this study, we aimed to assess the attitudes of Greek healthcare professionals toward mental illness and people suffering from it. Materials and methods: It is a non-interventional, analytic study, in which 479 health workers from a tertiary hospital in Thessaloniki, Greece, participated. Every single hospital service -except the personnel of the Psychiatric Clinic- was included in our study: from the cleaning service to the administrative staff and the auxiliary staff such as stretcher carriers, food and nutrition services' staff, and social workers, the nursing staff, and finally the attending physicians, taking into consideration that the psychiatric patient, from the moment he/she enters the hospital, consecutively gets in contact with every work grade of the healthcare establishment. Participants' attitudes concerning mental illness have been evaluated using the Opinions about Mental Illness Scale (OMI), the Social Distance Scale (SDS), and the Level of Contact Report (LCR-12). Results: Despite the high level of familiarity [as evaluated with LCR-12; mean score (µ): 8.82 ± 1.73], the employees displayed a rather poor willingness to interact with psychiatric patients (as measured with SDS; µ:11.68 ± 4.28), and endorsed significant prejudice toward individuals with mental disorders (assessed using OMI subscales; Social Discrimination µ: 22.99 ± 12.08, Social Restriction µ: 17.45 ± 9.07, Social Care µ: 21.04 ± 4.12, Social Integration µ: 16.38 ± 4.68, Etiology µ: 9.80 ± 4.95). Age and education stood out as the main determinants of participants' attitudes, with younger and highly educated participants to have shown a relatively refined profile. Conclusion: These results are not significantly improved compared to those of previous decades in Greek healthcare professionals and call for critical reflection and targeted stigma-reduction efforts.

9.
Public Health ; 204: 84-86, 2022 Mar.
Article En | MEDLINE | ID: mdl-35193032

OBJECTIVES: We explored the effectiveness of COVID-19 vaccines in preventing reinfection in the Republic of Cyprus. STUDY DESIGN: This was a matched case-control study (1:2). METHODS: Cases were adults with a first episode of SARS-CoV-2 infection in 2020 and a second episode (i.e. reinfection) between June and August 2021. Controls were adults with only one infection episode in 2020 (i.e. not reinfected). Matching was performed by age, gender, and week of diagnosis for the first episode. The reinfection date of a case was applied to the matched controls for estimating full or partial vaccination status. Cases and controls were classified as unvaccinated, partially vaccinated (i.e. vaccination series not completed or final dose received ≤14 days before the reinfection date), or fully vaccinated (i.e. final dose received >14 days before the reinfection date). Conditional logistic regression was performed to calculate odds ratios and 95% confidence intervals for full or partial vaccination, against no vaccination, between controls and cases. RESULTS: This study showed that controls were more likely to be vaccinated (odds ratio for full vaccination: 5.51, 95% confidence interval: 2.43-12.49) than cases. CONCLUSIONS: This finding answers a pressing question of the public and supports the offer of vaccination to people with previous SARS-CoV-2 infection.


COVID-19 , SARS-CoV-2 , Adult , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , Case-Control Studies , Cyprus/epidemiology , Humans , Reinfection , Vaccination
10.
Saf Sci ; 143: 105415, 2021 Nov.
Article En | MEDLINE | ID: mdl-34305320

The current COVID-19 crisis has changed our everyday lives almost in every aspect. Many people worldwide have died or hospitalised due to the severe impact of COVID-19 on the vulnerable population, and in particular to the elderly residents of long term care facilities (LTCF). The problem is amplified due to the fact that many of those occupants also suffer from comorbidities (e.g. respiratory and cardiovascular diseases, hypertension, etc.) and are therefore regarded as a susceptible host to severe COVID-19 disease. Impacts can be felt in the wider societal safety level. The aim of the present study is, therefore, to present the first National multimodal quality and safety improvement strategy plan for the LTCF in the Republic of Cyprus. The current program focused on the intensification of COVID-19 epidemiological surveillance, the promotion of educational training on best practises in infection control and prevention, and the implementation of additional non-pharmaceutical interventions (NPIs), according to the recommendations of ECDC (European Centre for Disease Prevention and Control) and WHO (World Health Organization). This innovative program fostered the interconnectivity and collaboration among the local authorities, academia and the local leaders of the LTCF. In addition, this program reinforced the importance of volunteerism and active participation of medical students in the National initiatives against the COVID-19 pandemic. The effectiveness of the adopted multimodal advanced care-safety planning program is appraised based on the reported new confirmed COVID-19 cases among LTCF healthcare workers and occupants, after the introducing and implementation of the selected NPIs. This multimodal strategy plan seems to be capable of reducing significantly the number of new cases of COVID-19 infections in LTCF and as a result, to also affect the residents' death number.

11.
Euro Surveill ; 26(2)2021 01.
Article En | MEDLINE | ID: mdl-33446304

The European monitoring of excess mortality for public health action (EuroMOMO) network monitors weekly excess all-cause mortality in 27 European countries or subnational areas. During the first wave of the coronavirus disease (COVID-19) pandemic in Europe in spring 2020, several countries experienced extraordinarily high levels of excess mortality. Europe is currently seeing another upsurge in COVID-19 cases, and EuroMOMO is again witnessing a substantial excess all-cause mortality attributable to COVID-19.


COVID-19/mortality , Mortality/trends , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/epidemiology , Cause of Death , Child , Child, Preschool , Computer Systems , Epidemiological Monitoring , Europe/epidemiology , Humans , Infant , Infant, Newborn , Middle Aged , SARS-CoV-2 , Young Adult
12.
J Clin Med ; 9(11)2020 Nov 08.
Article En | MEDLINE | ID: mdl-33171651

Coronavirus disease 2019 (COVID-19) has significantly affected the well-being of individuals worldwide. We herein describe the epidemiology of COVID-19 in the Republic of Cyprus during the first epidemic wave (9 March-3 May 2020). We analyzed surveillance data from laboratory-confirmed cases, including targeted testing and population screening. Statistical analyses included logistic regression. During the surveillance period, 64,136 tests (7322.3 per 100,000) were performed, 873 COVID-19 cases were diagnosed, and 20 deaths were reported (2.3%). Health-care workers (HCWs) represented 21.4% of cases. Overall, 19.1% of cases received hospital care and 3.7% required admission to Intensive Care Units. Male sex (adjusted Odds Ratio (aOR): 3.04; 95% Confidence Interval (CI): 1.97-4.69), increasing age (aOR: 1.56; 95%CI: 1.36-1.79), symptoms at diagnosis (aOR: 6.05; 95%CI: 3.18-11.50), and underlying health conditions (aOR: 2.08; 95%CI: 1.31-3.31) were associated with hospitalization. For recovered cases, the median time from first to last second negative test was 21 days. Overall, 119 primary cases reported 616 close contacts, yielding a pooled secondary attack rate of 12% (95%CI: 9.6-14.8%). Three population-based screening projects, and two projects targeting employees and HCWs, involving 25,496 people, revealed 60 positive individuals (0.2%). Early implementation of interventions with targeted and expanded testing facilitated prompt outbreak control on the island.

13.
Front Psychiatry ; 11: 842, 2020.
Article En | MEDLINE | ID: mdl-32973584

OBJECTIVE: The COVID-19 pandemic imposed a psychological burden on people worldwide, including fear and anxiety. Older adults are considered more vulnerable during public health emergency crises. Therefore, the aim of the present study was to investigate the psychological response of older adults during the acute phase of the pandemic in Greece. METHOD: This cross-sectional study was part of a larger three-day online survey. A total of 103 participants over the age of 60 fulfilled inclusion criteria. The survey included sociodemographic questions and six psychometric scales: the Fear of COVID-19 Scale (FCV-19S), the Brief Patient Health Questionnaire (PHQ-9) depression scale, the Generalized Anxiety Disorder scale (GAD-7), the Athens Insomnia Scale (AIS), the Intolerance of Uncertainty Scale (IUS-12), and the De Jong Gierveld Loneliness Scale (JGLS). RESULTS: A significant proportion of the participants reported moderate to severe depressive symptoms (81.6%), moderate to severe anxiety symptoms (84.5%), as well as disrupted sleep (37.9%). Women reported significantly higher levels of COVID-19-related fear, more severe depressive symptoms and sleep disturbances, as well as higher levels of intolerance of uncertainty. Participants living alone showed higher levels of loneliness. Intolerance of uncertainty was shown to modulate levels of loneliness. CONCLUSIONS: During the quarantine, attention was promptly drawn upon the risks related with older people's loneliness. Studies identifying factors that may contribute to loneliness during a public health emergency facilitate the implementation of supportive interventions. Preparedness to address and manage older people's loneliness may limit this deleterious emotional response during the pandemic, as well as at the post-COVID-19 phase.

14.
Psychol Trauma ; 12(7): 812-819, 2020 Oct.
Article En | MEDLINE | ID: mdl-32853011

Objective: The objective of this study was to assess the emergence of posttraumatic stress symptoms (PTSS) in Greek health care professionals during the COVID-19 pandemic. Method: A cross-sectional study was conducted via an online survey from April 10 until April 13, 2020. The survey included sociodemographic questions and the following psychometric tools: the Peritraumatic Distress Inventory, the Posttraumatic Stress Disorder-8 questionnaire, the Brief Patient Health Questionnaire Depression scale, the Athens Insomnia Scale, and 3 questions about negative perceptions of COVID-19. The survey was distributed through social media and comprises part of a larger survey targeting the general population. Altogether, 270 health care professionals responded to the survey. Results: Health care professionals appeared to be moderately stressed from the COVID-19 crisis, with women scoring higher on all clinical scales and the difference between women and men being statistically significant. Criteria for a probable posttraumatic stress disorder diagnosis were met by a total of 16.7% (21.7% of women; 5.1% of men). Negative emotion and threatened or physical tension are positive significant predictors of PTSS. Those suffering with higher levels of PTSS scored positively for insomnia and exhibited significantly higher peritraumatic distress. Conclusion: Health care professionals could benefit by being screened for PTSS and insomnia. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Betacoronavirus , Coronavirus Infections/psychology , Health Personnel/psychology , Pneumonia, Viral/psychology , Stress Disorders, Post-Traumatic/epidemiology , Adolescent , Adult , Aged , COVID-19 , Cross-Sectional Studies , Female , Greece/epidemiology , Health Personnel/statistics & numerical data , Humans , Male , Middle Aged , Pandemics , SARS-CoV-2 , Sex Factors , Young Adult
15.
Sci Signal ; 7(330): ra58, 2014 Jun 17.
Article En | MEDLINE | ID: mdl-24939894

Lemur tyrosine kinase 3 (LMTK3) is associated with cell proliferation and endocrine resistance in breast cancer. We found that, in cultured breast cancer cell lines, LMTK3 promotes the development of a metastatic phenotype by inducing the expression of genes encoding integrin subunits. Invasive behavior in various breast cancer cell lines positively correlated with the abundance of LMTK3. Overexpression of LMTK3 in a breast cancer cell line with low endogenous LMTK3 abundance promoted actin cytoskeleton remodeling, focal adhesion formation, and adhesion to collagen and fibronectin in culture. Using SILAC (stable isotope labeling by amino acids in cell culture) proteomic analysis, we found that LMTK3 increased the abundance of integrin subunits α5 and ß1, encoded by ITGA5 and ITGB1. This effect depended on the CDC42 Rho family guanosine triphosphatase, which was in turn activated by the interaction between LMTK3 and growth factor receptor-bound protein 2 (GRB2), an adaptor protein that mediates receptor tyrosine kinase-induced activation of RAS and downstream signaling. Knockdown of GRB2 suppressed LMTK3-induced CDC42 activation, blocked ITGA5 and ITGB1 expression promoted by the transcription factor serum response factor (SRF), and reduced invasive activity. Furthermore, abundance of LMTK3 positively correlated with that of the integrin ß1 subunit in breast cancer patient's tumors. Our findings suggest a role for LMTK3 in promoting integrin activity during breast cancer progression and metastasis.


Breast Neoplasms/pathology , GRB2 Adaptor Protein/physiology , Integrin beta1/physiology , Membrane Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Breast Neoplasms/enzymology , Breast Neoplasms/metabolism , Female , Humans , Neoplasm Invasiveness
16.
Chemosphere ; 89(4): 458-66, 2012 Oct.
Article En | MEDLINE | ID: mdl-22749935

In the present study were two favorite edible fish species for local residents, i.e., mandarin fish and crawfish, collected from the Shanghai market and analyzed for selected organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), hexabromocyclododecane (HBCDD), polybrominated diphenyl ethers (PBDEs) and methoxylated PBDEs (MeO-PBDEs). Efforts were also made to identify the potential sources of these contaminants. Comparable concentrations of hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and HBCDD were found in muscle tissue of mandarin fish from Guangdong (GDF), the Pearl River Delta and from Taihu Lake (TLF), the Yangtze River Delta. Levels of chlordanes, PCBs and PBDEs were about one magnitude lower in TLF compared to GDF. The concentrations of OCPs in the butter-like gland of the crawfish (CFB) were 2-5 times of those in the crawfish muscle (CFM) while concentrations of PCBs, PBDEs and MeO-PBDEs were comparable. The different patterns and levels of chlorinated and brominated organohalogen contaminants seen in mandarin fish from GDF and TLF indicates that different types of chemicals might be used in the two delta regions. The present study also shows a good correlation between the concentrations of hexachlorobenzene (HCB) and pentachloroanisol (PCA) in fish for the first time. Fish consumption limits based on chemical contaminants with non-carcinogenic effects were calculated. The estimated maximum daily consumption limit for GDF, TLF, CFM and CFB were 1.5, 2.6, 3.7 and 0.08 kg, respectively, indicating no significant risk regarding the persistent organic pollutants measured in the present study.


Astacoidea/metabolism , Environmental Exposure , Environmental Pollutants/metabolism , Food Contamination/analysis , Perciformes/metabolism , Animals , China , Environmental Monitoring , Gas Chromatography-Mass Spectrometry , Halogenated Diphenyl Ethers/metabolism , Humans , Hydrocarbons, Brominated/metabolism , Hydrocarbons, Chlorinated/metabolism , Lakes , Pesticides/metabolism , Polychlorinated Biphenyls/metabolism , Public Health , Risk Assessment , Rivers , Tissue Distribution
17.
Environ Sci Pollut Res Int ; 19(1): 139-47, 2012 Jan.
Article En | MEDLINE | ID: mdl-21698361

INTRODUCTION: Concentrations and congener profiles of polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs) in placenta samples from a Madrid population (Spain) are reported. Structure dependent retentions of OH-PCBs are known to occur in both humans and wildlife, making it of interest to assess placental transfer of both parent compounds and their metabolites to the developing foetus. RESULTS: The ΣPCB concentrations found in placenta samples were in the range 943-4,331 pg/g fresh weight (f.w.), and their hydroxylated metabolites showed a 20-time lower concentration level (53-261 pg/g f.w.). The PCB profiles were surprisingly dominated by CB-52 and CB-101 accounting for more than 44% of the total PCB concentration. This is indicating a source of exposure that is not yet identified. The OH-PCB profiles were dominated by 4-OH-CB187 and 4-OH-CB146, representing >50% of the ΣOH-PCB concentration of the placenta samples. Statistical analysis of the data revealed strong correlations between the PCB congeners, among some OH-PCBs, and between OH-PCB metabolites with a meta- and para- substitution pattern. Both PCB and OH-PCB concentrations presented homogeneous distribution, what allowed the establishment of a partial least squares model that correlated the concentrations of OH-PCB with those of PCBs in placenta samples. In addition, causal correlations were observed between the concentrations of OH-PCBs and those of their corresponding PCB precursors.


Environmental Monitoring , Environmental Pollutants/toxicity , Placenta/drug effects , Polychlorinated Biphenyls/toxicity , Adult , Cities , Environmental Pollutants/chemistry , Environmental Pollutants/metabolism , Female , Humans , Hydroxylation , Multivariate Analysis , Placenta/chemistry , Placenta/metabolism , Polychlorinated Biphenyls/chemistry , Polychlorinated Biphenyls/metabolism , Pregnancy , Spain
18.
Chemosphere ; 82(6): 839-46, 2011 Feb.
Article En | MEDLINE | ID: mdl-21122890

A method was developed to study reductive transformation of highly brominated diphenyl ethers (BDEs). The method development is a part of a broader project where it will be used to determine the susceptibility of environmental pollutants to reductive conditions, in an attempt to create a scheme for determination of chemical's persistence. This paper focuses on identification of octabrominated diphenyl ether transformation products from reductive debromination of the three nonabrominated diphenyl congeners (nonaBDE), BDE-206, -207 and -208. Sodium borohydride was used to explore the reductive debromination of the nonaBDEs. The transformation products were collected at two time-points and identified products were quantified by GC-MS. The reduction of the nonaBDEs lead primarily to debrominated products, mainly octaBDEs. The three nonabrominated DEs gave isomer-related transformation product patterns. BDE-207 and BDE-208 showed a propensity for ortho-debromination in the initial reaction step, while no discrimination between initial debromination positions was seen for BDE-206. All three nonabrominated DEs displayed a preferred initial debromination on the fully brominated DE ring.


Borohydrides/chemistry , Environmental Pollutants/chemistry , Halogenated Diphenyl Ethers/chemistry , Environmental Pollutants/analysis , Gas Chromatography-Mass Spectrometry , Halogenated Diphenyl Ethers/analysis , Halogenation , Oxidation-Reduction
19.
Environ Toxicol Chem ; 29(12): 2653-9, 2010 Dec.
Article En | MEDLINE | ID: mdl-20891018

In the present study, muscle and liver tissue from 10 female Greenland sharks (Somniosus microcephalus) collected in Icelandic waters were analyzed for neutral and phenolic brominated organic compounds, including polybrominated diphenyl ethers (PBDEs) and the structurally related methoxylated (MeO) and hydroxylated (OH) PBDEs. Hydroxylated PBDEs exist both as natural products and as metabolites of the anthropogenic PBDEs, whereas MeO-PBDEs appear to exclusively be of natural origin. Other compounds examined were 2',6-dimethoxy-2,3',4,5'-tetrabromodiphenyl ether (2',6-diMeO-BDE68), 2,2'-dimethoxy-3,3',5,5'-tetrabromobiphenyl (2,2'-diMeO-BB80), 2,4,6-tribromoanisol (2,4,6-TBA) and 2,4,6-tribromophenol, all of natural origin, although 2,4,6-TBA and its phenolic counterpart may also be of anthropogenic origin. The major brominated organic compound was 6-MeO-BDE47, and ΣMeO-PBDE ranged from 49 to 210 ng/g fat in muscle and from 55 to 200 ng/g fat in liver tissue. Total concentrations of PBDEs were lower than ΣMeO-PBDE, in all but one sample, ranging between 7.3 to 190 and 9.9 to 200 ng/g fat in muscle and liver, respectively, and major congeners were BDE-47, BDE-99, and BDE-100. Polybrominated diphenyl ethers were analyzed using both high- and low-resolution mass spectrometry (MS) as a quality assurance, and the results from this comparison were acceptable. In accordance with previous work on Greenland sharks, no size/age-related accumulation was observed. Differences seen in concentrations were instead assumed to be a reflection of different feeding habits among the individuals. Phenolic compounds were only formed/retained in trace amounts in the Greenland shark. Among the phenolic compounds studied were 6-OH-BDE47, 2'-OH-BDE68, and 2,4,6-tribromophenol, all detected in liver and the latter two in muscle.


Halogenated Diphenyl Ethers/chemistry , Halogenated Diphenyl Ethers/metabolism , Sharks/metabolism , Animals , Atlantic Ocean , Environmental Monitoring , Female , Greenland , Halogenated Diphenyl Ethers/analysis , Liver/chemistry , Liver/metabolism , Muscles/chemistry , Muscles/metabolism
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