Papers by Thanasis Alegakis
Toxics, 2014
, lead (Pb) and mercury (Hg) are toxic metals with increasing interest due to their tendency to b... more , lead (Pb) and mercury (Hg) are toxic metals with increasing interest due to their tendency to bioaccumulate in fish tissue which may pose a threat to human health via fish consumption. This review of the recent literature on Cd, Pb, Hg levels summarizes data of fish biomonitoring studies in the Mediterranean Sea in order to determine potential risks due to dietary intake of metals. The analytical methods applied are described, with Atomic Absorption Spectroscopy and Inductively Coupled Plasma Mass Spectroscopy being the most popular. Most of the literature reviewed is focused on the Eastern Mediterranean. Results from the studies indicate that metals mostly accumulate in liver, followed by muscle. Although there are few studies reporting metal levels in fish exceeding the maximum residue levels (MRLs), the bulk of the studies cite levels below the MRLs. The hazard index (HI) of fish consumption, namely the ratio of estimated weekly intake to provisional tolerable weekly intake (EWI/PTWI) was estimated for adult consumers and no risk emerged. The EWI/PTWI ratios of lead and mercury for Italy Toxics 2014, 2 418 (0.14 and 0.22 respectively) represent the highest HI levels estimated. In view of maximizing the benefits while minimizing the risks of fish consumption, a more detailed fish-specific database on intakes for consumers is required and extended bimonitoring in as many regions as possible.
BMC ear, nose, and throat disorders, Jan 7, 2006
In Greece, primary care is still developing. The aim of this study was to define the epidemiologi... more In Greece, primary care is still developing. The aim of this study was to define the epidemiologic profile of common otorhinolaryngological, head and neck disorders in order to help general practitioners to deal with them in a primary care future. A total of 6771 patients attended the Otorhinolaryngology emergency department of the University General Hospital of Heraklion (Crete), between January and December 2004. All cases were included in this retrospective study. The registry of the Otorhinolaryngology emergency department was analysed and age, sex, seasonality and clinical diagnosis were tabulated. All patients were evaluated by Otorhinolaryngologists. The classification of the cases was based on the main symptom or clinical sign that conditioned the reason for seeking care. Diagnoses were also coded according to the International Classification of Diseases (ICD-10). The male to female ratio was 1:1. The mean age for females was 36.3 years standard deviation (SD): 21.1 and for ...
Toxicology Letters, 2012
The aim of this study is to determine the glutathione s transferase polymorphisms (GSTO1*A140D an... more The aim of this study is to determine the glutathione s transferase polymorphisms (GSTO1*A140D and GSTO2*N142D) in Turkish population and investigate whether this polymorphism has an effect on arsenic levels in placenta and maternal biological samples. Graphite Furnace Atomic Absorption Spectrometry (GFAAS) equipped with Zeeman background correction system was utilized for arsenic determination. The genotype and allele frequencies of GSTO1*A140D and GSTO2*N142D polymorphisms in the Turkish population were determined by PCR-RFLP technique. The genotype frequencies of the GSTO1*A140D and GSTO2*N142D gene polymorphisms were determined as follows; 51.3% and 43.4% homozygote typical, 38.9% and 44.9% heterozygote, and 9.8% and 9.7% homozygote atypical genotype in our society. The allele frequencies of 140D and 142D in the entire study population were 29.2% and 33.8%, respectively. A high negative correlation coefficient was detected between the arsenic concentrations of placenta and cord blood (r = −0.23 and p < 0.01). Similarly, a high negative correlation coefficient was calculated between the concentrations of maternal blood and hair (r = −0.27 and p < 0.01). Moreover, a negative correlation coefficient was found between the arsenic levels of maternal and cord blood (r = −0.28 and p < 0.05). In conclusion, even though significant increases observed in arsenic concentrations of the blood of mothers were in parallel with significant increases seen in the placenta as well, it was ascertained that the adsorbent role of placenta leads to concentration decreases seen in cord blood. Consequently, in terms of arsenic metabolism, GSTO1 and GSTO2 polymorphisms have significant role among individuals.
Toxicology Letters, 2014
h i g h l i g h t s • Our aim was to evaluate the possible association between hypospadias and pe... more h i g h l i g h t s • Our aim was to evaluate the possible association between hypospadias and pesticide exposure. • We determined pesticides in samples from children with hypospadias and their parents. • Hypospadiac boys and their parents were found to be exposed to pesticides. • Our data support the hypothesis that organophosphate and organochlorine pesticide exposure may be a potential risk factor for hypospadias.
Toxicology Letters, 2009
S233 metabolites to edible tissues including milk, meat and eggs was estimated. In most cases, no... more S233 metabolites to edible tissues including milk, meat and eggs was estimated. In most cases, no risks to animal health were identified at the level of normal feed intake of farm animals under European standards of good animal feeding practice at the current statutory levels (EU/32/2002). However, worst-case scenarios using the maximum or even elevated levels of feed contamination showed potential for adverse effects, e.g. in pigs (deoxynivalenol), cats (methyl-mercury), gossypol (sheep) and theobromine in dogs and horses. Data gaps were identified with regard to toxicity, toxicokinetics, rate of carry over and amounts of residues of these undesirable substances in animal products. Despite these gaps, the CONTAM Panel concluded that the risk of adverse health effects in humans consuming animal products (meat, eggs and milk) containing residual amounts of these compounds would be low.
Hematological Oncology, 2011
Angiogenesis is a complex process essential for the growth, invasion, and metastasis of various m... more Angiogenesis is a complex process essential for the growth, invasion, and metastasis of various malignant tumours, including multiple myeloma (MM). Various angiogenic cytokines have been implicated in the angiogenic process. Among them, platelet-derived growth factor-AB (PDGF-AB) has been reported to be a potent stimulator of angiogenesis in many solid tumours and haematological malignancies, including MM. The aim of the study was to investigate the relationship between PDGF-AB, microvascular density (MVD), and various angiogenic cytokines, such as basic fibroblast growth factor (b-FGF), angiogenin (ANG), and interleukin-6 (IL-6), in MM patients. Forty-seven MM patients before treatment, 22 of whom were in plateau phase, were studied. We determined the serum levels of the aforementioned cytokines and MVD in bone marrow biopsies before and after treatment. Mean serum values of PDGF-AB, b-FGF, ANG, and MVD were significantly higher in patients compared with controls and with increasing disease stage. Significant positive correlations were observed between serum PDGF-AB, ANG, and IL-6 levels and MVD. Furthermore, we found significant positive correlations between PDGF-AB and b-FGF, IL-6, ANG, and b2 microglobulin. We also found that patients with high MVD had statistically significantly higher serum levels of PDGF-AB when a median MVD value of 7.7 was used as the cutoff point. Furthermore, a significant difference was found in serum levels of PDGF-AB between pre-and post-treatment patients. Finally, survival time was significantly higher in the low MVD group versus the high MVD group (76 vs 51 months). Our results showed that there is a strong positive correlation between PDGF-AB and the studied angiogenic cytokines and MVD. It seems that PDGF-AB plays a role in the complex network of cytokines inducing bone marrow neovascularization in patients with MM.
Food and Chemical Toxicology, 2013
Occurrence of aflatoxin M1 (AFM1) was determined in 196 milk samples (conventional, organic and k... more Occurrence of aflatoxin M1 (AFM1) was determined in 196 milk samples (conventional, organic and kids milk) from the Greek market during November 2009 to June 2010. AFM1 content was analyzed using an Enzyme-Linked Immunosorbent Assay (ELISA) commercial kit. Aflatoxin M1 was detected in 46.5% of the samples. 46.5% of the samples were found positive for AFM1. The most frequent range of detection was between 5 and 10 ng/l. Based on the EU regulation only 2 mil k samples presented AFM1 levels higher than the maximum residue limits. Two different scenarios were used for the determina tion of hazard index: (a) scenario 1 using only positive (detected AFM1) samples and (b) scenario 2 when missing values where imputed with Limit of Detection (LOD) divided by 2. Significant statistical differenc es between different milk categories were presented only when the results were imputed with LOD/2 values. Exposure assessment scenarios were developed for ages 1, 3, 5, 7 and 12 and their respective estimated weights and daily milk consumpt ion. Under the worst-case scenario all milk types presented a Hazard Index (HI) less than one. The highest HI values appear in the ages of 1-3.
European Journal of Internal Medicine, 2012
Background: Τhe importance of angiogenesis in malignancies' growth is well recognized. CD105 (End... more Background: Τhe importance of angiogenesis in malignancies' growth is well recognized. CD105 (Endoglin), a proliferation-associated glycoprotein, is a powerful marker of neovascularization. Elevated amounts of soluble CD105 (sCD105) have been identified in selected solid tumors. The aim of the study was to estimate circulating levels of sCD105 and soluble transforming growth factor-β 1 (sTGF-β 1 ), in multiple myeloma (MM) patients, to determine their significance in tumor progression and to investigate the correlation between sCD105 and markers of disease activity. Methods: We studied 50 newly diagnosed MM patients. Twenty-five of them were also investigated in plateau phase. Twenty patients with monoclonal gammopathy of undetermined significance (MGUS) were enrolled in this study. As control group 28 healthy persons were studied. We determined sCD105, sTGF-β 1 and interleukin-6 (IL-6) in the serum, Ki-67 proliferation index (Ki-67 PI) expression and microvascular density (MVD) in bone marrow with immunohistochemistry. Results: The mean concentrations of sCD105 and IL-6 were higher in MM and MGUS patients compared to controls, whereas serum levels of sTGF-β 1 were lower in MM patients compared to MGUS patients and controls. sCD105 levels, were significantly different among disease stages, with higher values in advanced stages. It was found that sCD105 correlated with Ki-67 PI, MVD and IL-6. Conclusions: CD105 seems to play an important role in angiogenesis and tumor progression. Circulating levels of sCD105 could detect patients with more advanced disease and might help in evaluating the response to treatment.
European Journal of Cancer Care, 2009
Psychometric properties of the QLQ-C30 (version 3.0) in a sample of ambulatory Cretan cancer pati... more Psychometric properties of the QLQ-C30 (version 3.0) in a sample of ambulatory Cretan cancer patients The aim of the present study was to test the psychometric properties of the Quality of Life Questionnaire (QLQ-C30, version 3.0) in a sample of ambulatory cancer patients, mostly low educated and coming from rural areas of the island of Crete. The sample consisted of 188 lung, breast and colorectal cancer patients. Their quality of life (QoL) has been evaluated twice: before and after the first therapeutic intervention. Alpha coefficients ranged from 0.88 to 0.98. Inter-scale correlations were more substantial between the physical, role and fatigue scales. Mean score differences between groups of patients with different performance status (PS) were statistically significant for most of the sub-scales. Instead the patients with stable PS after treatment showed worse functioning in five from the nine sub-scales. For those whose PS has deteriorated, their subjective evaluation indicated deterioration only for physical, role and social functioning. In this sample of mainly ambulatory cancer patients, the instrument has high coefficients of reliability and good clinical validity. However, the results related to its sensitivity are not very consistent. It has proven able to detect clinically significant changes after the therapeutic intervention only for the patients who deteriorated over time and for three specific dimensions of QoL: physical, role and social functioning.
CHEST Journal, 2005
To measure the prevalence of allergic rhinitis, atopy, and asthma among grape farmers, and to com... more To measure the prevalence of allergic rhinitis, atopy, and asthma among grape farmers, and to compare the respiratory and atopic status in grape farmers with those of nonexposed control subjects. Cross-sectional study. Malevisi region in northern Crete, Greece. One hundred twenty grape farmers and 100 control subjects living in the Malevisi region were examined. The protocol comprised a questionnaire, skin prick tests for 16 common allergens, measurement of specific IgE antibodies against 8 allergens, and spirometry before and after bronchodilation. Grape farmers were found to have an excess of respiratory symptoms. The comparison with the control group, after adjusting for age, sex, and smoking status, showed that the differences were statistically significant for rhinorrhea (odds ratio [OR], 2.7; 95% confidence interval [CI], 1.5 to 5.1; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001), sneezing (OR, 2.2; 95% CI, 1.2 to 4.0; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01), and nasal itching (OR, 1.9; 95% CI, 1.0 to 3.6; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05), but were nonsignificant for asthma-related symptoms. In the multiple logistic regression model, grape farmers were found to have increased work-related symptoms, such as sneezing (OR, 2.9; 95% CI, 1.3 to 6.6; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 01), rhinorrhea (OR, 2.9; 95% CI, 1.3 to 6.6; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01), cough (OR, 3.7; 95% CI, 1.2 to 11.4; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05), and dyspnea (OR, 3.8; 95% CI, 1.1 to 1.3; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). The prevalence of allergic rhinitis was 40.8% in grape farmers and 26% in control subjects (OR, 2.0; 95% CI, 1.1 to 3.5; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.02). Increased but statistically nonsignificant values of asthma prevalence were found in grape farmers (6.7%) compared with the control group (2.0%). The prevalence of atopy was 64.2% in grape farmers and 38.0% in the control group (OR, 2.2; 95% CI, 1.2 to 3.5; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). Mean FEV1 was significantly lower in grape farmers than in control subjects (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05), after adjusting for age, sex, and smoking status. Bronchial obstruction was reversible in 23 grape farmers (19.2%) and in 6 control subjects (6%; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). The study mainly demonstrated the high prevalence of allergic rhinitis and work-related respiratory symptoms in grape farmers compared to control subjects. It also suggested that grape farming is possibly associated with increased allergic sensitization to specific pollens, low baseline FEV1, and increased bronchial hyper-responsiveness. Further studies are needed to determine the potential risk factors for these disorders among the farming population.
Toxicology Letters, 2012
Although rice and corn are two main cash crops in Lombardy (North Italy) and their cultivation in... more Although rice and corn are two main cash crops in Lombardy (North Italy) and their cultivation involves several thousands of farmers, risk assessment of pesticide exposure is rarely done, especially in small and medium sized enterprises. With the use of pads for environmental monitoring (OECD protocol), of preand post-exposure 24 h urine collection for biological monitoring and of hand wash for hands' exposure, we measured the exposure of 28 agricultural workers to propanil and terbuthylazine in real-life working conditions. In propanil applicators, median daily exposure on the clothes was 73.5 mol per worker, while the exposure on the skin was 22.4 mol. For terbuthylazine, these exposures were 37.2 mol and 0.86 mol per worker, respectively. Median excretion of the propanil metabolite (3,4-dichloroaniline) after exposure was 84 nmol in 24 h urine, and 13 nmol for the metabolite of terbuthylazine. Risk assessment performed by comparing to the AOELs of the applied active ingredients with an estimated internal dose, obtained based on the measured levels of skin and hand exposure and the percentage of dermal absorption of the active ingredients considered showed that 4 propanil workers, and no terbuthylazine workers, were overexposed. Our study helps define and confirm relationships between different exposure determinants, which can be used in the development of tools for risk assessment of exposure to pesticides in small and medium sized enterprises.
Anticancer research
Background: Based on the hypothesis that Fractal Dimension (FD) reflects heterogeneity of tumor t... more Background: Based on the hypothesis that Fractal Dimension (FD) reflects heterogeneity of tumor tissue, we performed an image analysis study to calculate FD of tissue specimens from patients with laryngeal carcinomas in order to investigate its prognostic value. Materials and Methods: Laryngectomy specimens from 52 patients, who had previously undergone total laryngectomy for squamous cell carcinomas, were examined and their history files reviewed. Ten patients were lost from follow-up. Fractal Analysis software was used to estimate FD of histology sections by the box-counting method. FD of carcinomatous areas was correlated with survival. Results: Patients with a FD lower than the median value of the sample, estimated in sections of carcinomas, had statistically significant higher survival rates. Conclusion: Within the sample of patients studied, FD could be used as a prognostic factor.
International journal of immunopathology and pharmacology
Veterinary and human toxicology
Nine human acute poisonings due to intentional ingestion of organophosphorous pesticides are pres... more Nine human acute poisonings due to intentional ingestion of organophosphorous pesticides are presented. Six of the victims died. Six patients were treated in the Intensive Care Unit (ICU) from 34 h to 45 d, while 3 were found dead by relatives. Two of the patients treated in the ICU fully recovered after 15 and 24 d while the third survivor developed delayed neuropathy. Organophosphate blood levels were determined on admission and during therapy, and in 1 case atropine and pralidoxime levels were also detected. Significant fluctuations of the plasma cholinesterase activity were observed during therapy. Postmortem analysis revealed higher levels of pesticides in organs (eg 23.1 micrograms fenthion/g kidney) and in fat (135.2 micrograms fenthion/g) than in blood (eg 4.8 micrograms fenthion/ml) and vitreous humor. Considerable pesticide was measured in testis (eg 5.8 micrograms fenthion/g, 0.8 micrograms methidathion/g) and uterus (170.5 micrograms malathion/g). Extracorporeal decontamination to enhance pesticide elimination is a therapeutic challenge.
Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine
The purpose of this study was to ultrasonographically evaluate spleen dimensions in healthy prema... more The purpose of this study was to ultrasonographically evaluate spleen dimensions in healthy prematurely born neonates and infants during the first 3 months of life. Ninety-six neonates and infants aged from 2 to 90 days, with gestational ages from 25 to 35 weeks, were prospectively examined between 2001 and 2003. None had either infectious or other serious diseases or congenital disorders. The relationships between the ultrasonographically measured spleen size parameters and postmenstrual age, sex, gestational age, and somatometric parameters (height, weight, and body surface area) were studied with linear regression models with backward selection. Spleen dimension growth curves and upper/lower limits defined by the upper/lower 95% confidence interval were presented in graphs by height, weight, and body surface area. In addition, spleen length was compared with recently published data on term peers. All spleen dimensions were positively correlated with postmenstrual age and somatometric parameters. Sex did not influence the variability of spleen dimensions. Spleen length had lower values and a smaller rate of growth in preterm than term neonates and infants. We have provided ultrasonographic spleen volumetric values in preterm neonates and infants during the first 3 months of life, giving reference standards applicable for clinical practice or research purposes.
Toxics, 2014
Cadmium (Cd), lead (Pb) and mercury (Hg) are toxic metals with increasing interest due to their t... more Cadmium (Cd), lead (Pb) and mercury (Hg) are toxic metals with increasing interest due to their tendency to bioaccumulate in fish tissue which may pose a threat to human health via fish consumption. This review of the recent literature on Cd, Pb, Hg levels summarizes data of fish biomonitoring studies in the Mediterranean Sea in order to determine potential risks due to dietary intake of metals. The analytical methods applied are described, with Atomic Absorption Spectroscopy and Inductively Coupled Plasma Mass Spectroscopy being the most popular. Most of the literature reviewed is focused on the Eastern Mediterranean. Results from the studies indicate that metals mostly accumulate in liver, followed by muscle. Although there are few studies reporting metal levels in fish exceeding the maximum residue levels (MRLs), the bulk of the studies cite levels below the MRLs. The hazard index (HI) of fish consumption, namely the ratio of estimated weekly intake to provisional tolerable weekly intake (EWI/PTWI) was estimated for adult consumers and no risk emerged. The EWI/PTWI ratios of lead and mercury for Italy
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Papers by Thanasis Alegakis