Search PubMed⌕ Search

Biomedical subjects

A Koutselinis

Publications and source records attributed to A Koutselinis.

At least 19 recordsLinked to original sources
PubMed2003

Occupational exposure to cholinesterase inhibiting pesticides: a Greek case.

The determination of plasma or serum cholinesterase is absolute and it is considered as a reliable index of exposure in workers of organophosphorus pesticides industries. In the present study the plasma cholinesterase of 28 persons working in the packaging of an ortho-thio-phosphate was determined, before and after their exposure to this agent. The results of this study showed a plasma cholinesterase depression of 37%, a decrease which was statistically significant (P<0.001).

Adult↗
PubMed2003

Assessing food additive toxicity using a cell model.

Food additives are widely used for technological purposes and their presence is often substantial daily diet. They have also been accused forvarious toxic reactions in humans. The toxicity of the food color tartrazine, the preservatives sodium nitrate and sodium benzoate, and the antioxidant BHT, was studied using the protozoan Tetrahymenapyriformis as a toxicological model. The 4 food additives were added to Tetrahymena cultures and DNA content of the protozoan nuclei measured by an image analysis system. These food additives caused a statistically significant increase in DNA content suggesting stimulation of the mitotic process. This system may contribute to the investigation of the cellular action of food additives, since mitogenic stimuli substantially alter susceptibility to chemical carcinogenesis.

Animals↗
PubMed2002

Expression of metallothionein in lung carcinoma: correlation with histological type and grade.

AIMS: Over-expression of cellular metallothionein occurs frequently in human tumours but the underlying mechanism remains unknown. The aim of this study was to assess metallothionein expression in cases of lung carcinoma and to correlate it with histopathological parameters. METHODS AND RESULTS: Tumour tissue samples from 89 patients with lung carcinoma were immunostained by the streptavidin-biotin-peroxidase technique, using a monoclonal antibody against both metallothionein-1 and -2 isoforms. Positive matallothionein immunostaining was prominent in 44 out of 89 (49%) and negative in 45 out of 89 (51%) cases of lung carcinoma examined. Metallothionein positivity was prominent in 32 out of 43 (74%) cases of squamous cell lung carcinoma, and in 12 out of 35 (34%) cases of adenocarcinoma, while it was negative in all 11 cases of small-cell lung carcinoma examined, presenting a statistically significant difference between the different histological types. The intensity of metallothionein staining revealed a statistically significant difference between the squamous cell and adenocarcinoma cases examined. The pattern and extent of metallothionein staining in tumour cells and the expression of metallothionein in stromal cells were not correlated with histopathological parameters (type and grade) in metallothionein-positive cases of lung carcinoma examined. No association was found between metallothionein expression and lymph node status in the examined cases of lung carcinoma. CONCLUSIONS: Our findings indicate that expression of metallothionein was evident in squamous cell lung carcinoma and adenocarcinoma, but absent in small-cell lung carcinoma, supporting evidence for participation of this protein in the biological mechanisms underlying the carcinogenic evolution in the lung.

Adenocarcinoma↗
PubMed2002

Countrywide estimation of the burden of injuries in Greece: a limited resources approach.

BACKGROUND: We have assessed the ability of the Emergency Department Injury Surveillance System (EDISS), a registration network operating with limited resources, to predict the burden and pattern of injuries in the whole Greece. METHODS: We have compared hospitalizations calculated on the basis of EDISS with those routinely recorded by the National Statistical Service countrywide. EDISS relies on data collected in the Emergency Departments of four hospitals, two located in the Greater Athens area, and two district hospitals in the remaining Greece. EDISS data concern hospitalized and non-hospitalized patients of all ages, with all types of injuries irrespectively of their etiology or intent. RESULTS: Over a three-year period 148 835 subjects with injuries were interviewed. Using sampling ratios of 2.2% for all injuries outside Greater Athens and for adults in Greater Athens but 28.9% for childhood injuries, the total annual number of injuries in Greece was estimated at 1.53 million (95% confidence interval: 1.48-1.57 million). Of those, about 18% concern children less than 15 years old. The difference between the EDISS estimated and the actually recorded hospitalized injuries was, in preliminary terms, acceptable. DISCUSSION: Of the ten major categories of injuries, seven among children and five among adults have shown deviations of less than 20%. For the remaining categories deviations were larger but in only one instance did the difference exceed 50%. It is concluded, that for a small and relatively homogeneous country, like Greece, injury data provided by four large hospitals can generate reasonably reliable estimates for large categories of injuries.

Adolescent↗
PubMed2001

Analysis of total mercury in human tissues prepared by microwave decomposition using a hydride generator system coupled to an atomic absorption spectrometer.

A fast and efficient procedure has been developed for the analysis of total mercury in human tissues and blood using a hydride vapor generator system coupled to an atomic absorption spectrometer (HVG-AA). Tissue and blood samples were digested in a pressurized microwave decomposition system and the digest diluted prior to formation of free mercury vapor and analysis by atomic absorption. Recovery studies performed on 10 spiked/unspiked pairs of human liver and on 10 spiked/unspiked pairs of human blood samples yielded average recoveries of 99.7% (CV=0.4%) and 101.2% (CV=0.5%), respectively. The method detection limit for liver and blood was 50 microg Hg/kg and 12.5 microg Hg/l, respectively. The "normal" concentrations of mercury in human liver and blood are 33-490 microg Hg/kg and 0.6-59 microg Hg/l, respectively [1]. This method is able to determine mercury poisoning levels and may also be applied to detect mercury near the lower levels of these "normal" ranges, using the standard addition method approach.

Forensic Medicine↗
PubMed2001

Immunomodulative effects of aflatoxins and selenium on human natural killer cells.

The possible immunomodulative effects of aflatoxin B1 and selenium (as sodium selenite) at concentrations lower than 5.10(-11) M or 0.05ppb and 10(-5) M, respectively on natural killer (NK) cells from healthy volunteers were evaluated by a 51Cr release natural killer assay. Aflatoxin B1 and selenium separately had an immunosuppressive effect on NK cell activity. When they were studied in combination, they caused a statistically significant increase of the cytotoxic activity of NK cells in the presence of the lowest concentrations of aflatoxin B1 (0.005ppb) and of sodium selenite (10(-8)M).

Adjuvants, Immunologic↗
PubMed2001

Lead content of fresh milk samples from different sites in Athens.

Milk and dairy products constitute a major food, especially for infants and children, and relatively low levels of toxic elements can contribute significantly to dietary intakes and be hazardous for public health. The purpose of this survey was to define the levels of lead in milk samples of different origin, to establish the presence or absence of contamination. The milks from different sites of the metropolitan area of Athens contained negligible traces of lead and thus are safe for the public health.

Animals↗
PubMed2000

Identification of an alleged offender of murder by VNTR analysis: case report.

DNA typing was used to demonstrate that three human body pieces found disposed of in the countryside around Athens and the suspicions about the perpetrator's identity were connected. Reverse paternity testing was attempted by comparative typing of three variable number tandem repeats loci in the remains, as well as in the presumptive parents and sister of the decedent, demonstrating Mendelian inheritance of the alleles of the loci analyzed. Confronting the results of the abovementioned analysis, the suspect accepted the accusation.

Adult↗
PubMed2000

Delat9-tetrahydrocannabinol content in cannabis plants of greek origin.

The delta9-tetrahydrocannabinol (delta9-THC) content was identified and determined quantitatively using a Gas Chromatography Detector (Gas Chromatography-Electron Ion Detector) instrument in samples of illicit herbal cannabis. Law enforcement authorities sent the samples to the Department of Forensic Medicine and Toxicology, University of Athens, for toxicological analysis. The concentrations of delta9-THC in these samples ranged from 0.08% to 4.41%. Such concentrations suggest that Greece might be at high risk, as an area for the illicit cultivation of "pedigree" cannabis plants. The forensic aspects of cannabis classification are discussed.

Cannabis↗
PubMed2000

Cytotoxic and immunomodulative effects of flunitrazepam, zipeprol and trihexyphenidyl on human peripheral blood lymphocytes.

The cytotoxic effects of flunitrazepam, zipeprol and trihexyphenidyl on cell viability of peripheral blood mononuclear cells from healthy volunteers were studied at concentrations from 10(-2) to 10(-8) M by 2 colorimetric in vitro assays: the neutral red uptake assay and thiazolyl blue tetrazolium bromide assay. All tested drugs of abuse were non-cytotoxic at concentrations lower than 10(-5) M. Possible immunomodulative effects of these substances were evaluated through phytohemagglutinin induced lymphocyte proliferation ([3H]-thymidine DNA incorporation assay) and by a 51Cr release natural killer assay. The 3 drugs studied produced statistically significant immunomodulative alterations on both immunological parameters.

Adjuvants, Immunologic↗
PubMed2000

The importance of performing in vitro cytotoxicity testing before immunomodulation evaluation.

This study uses the well known sensitive and reproducible human peripheral blood lymphocyte (PBL) assay as a model for the possible discrimination between cytotoxic and/or immunomodulative properties of 5 reference compounds: cadmium chloride (CdCl2): didodecyl-dimethyl ammonium bromide (DDAB); cyclosporin (CsA); dexamethasone (DEXA); and theophylline. Two colorimetric cytotoxicity assays were employed, the thiazolyl blue tetrazolium bromide and neutral red, and the H-thymidine DNA incorporation assay on phytohemagglutinin stimulated or non-stimulated PBL was used, as a parameter of cell mediated immunity. This study demonstrated the importance of performing colorimetric or other cytotoxicity assays before any investigation of mechanisms of action of different substances on immunomodulation and relative human risk assessment. This study showed that CdCl2 and DDAB have a cytotoxic rather than immunomodulative effect on PBL and that CsA, DEXA and to a lesser extent theophylline have immunomodulative rather than cytotoxic effects on PBL within the range of the concentrations studied.

Antineoplastic Agents, Hormonal↗
PubMed1999

The use of alcohol and other psychoactive substances by victims of traffic accidents in Greece.

Alcohol is one of the main causes of traffic accidents worldwide. Its use decreases significantly the driving ability of an individual as well as the reflexes of a pedestrian increasing in this way the possibilities of their involvement in motor-vehicle accidents. The above possibilities are increased when a psychoactive substance has been taken in combination with alcohol due to their synergistic effect. The Laboratory of Forensic Medicine and Toxicology of the University of Athens is authorized to perform the toxicological investigation of traffic accidents that happen in the major part of Greece. The findings of the toxicological analyses that were performed in our laboratory during the years 1995 to 1997 are classified according to the alcohol concentration and the kind of psychoactive substance detected as well as to the gender and the age of the victims, drivers or pedestrians. The results of the above classification are evaluated and the conclusions regarding alcohol, drugs and traffic accidents in Greece are discussed thoroughly.

Accidents, Traffic↗
PubMed1999

Flour contamination as a source of lead intoxication.

CASE REPORT: A 43-year-old man was hospitalized because of severe anemia and recurrent bouts of abdominal pain over 20 days. There was no known occupational exposure to toxins. Concomitantly, the patient's father complained of having the same symptoms. Familial lead poisoning was diagnosed when all 6 family members tested had high blood leads (31-64 micrograms/dL). RESULTS: Following detailed examination of the potential sources common to all members of the household, the cause of poisoning was determined to be corn flour containing 38.7 mg/g lead. Physicians are reminded to consider lead poisoning in the differential diagnosis of individuals with unexplained symptoms, particularly those of abdominal discomfort and anemia.

Abdominal Pain↗
PubMed1999

Immunomodulative effects of some drugs of abuse on human peripheral blood lymphocytes.

The cytotoxic effects of opiates, cocaine and their metabolites on peripheral blood mononuclear cells from healthy volunteers, concerning cell viability, were studied in a wide range of concentrations (ranging from 10-(2) to 10-(8) M), by 2 colorimetric in vitro assays, the neutral red uptake assay and thiazolyl blue tetrazolium bromide assay. All tested drugs of abuse and their metabolites were non-cytotoxic at concentrations lower than 10-(5) M. The possible immunomodulative effects of these substances were evaluated through phytohemagglutinin-induced lymphocyte proliferation ([3H]-thymidine DNA incorporation assay) as well as by a 51Cr release natural killer assay. The results showed immunomodulative effects of all the opiates tested. Cocaine, freebase cocaine and benzoylecgonine produced a statistically non-significant decrease of phytohemagglutinin proliferation. Cocaine induced a statistically non-significant increase, whereas freebase cocaine and benzoylecgonine showed a non-significant decrease of natural killer cell activity.

Adult↗
PubMed1998

Evidence of apoptosis in human carotid atheroma.

PURPOSE: Apoptosis is a morphologically distinct form of programmed cell death that plays a major role in cellular development and homeostasis. In this study, we examined the role that apoptosis may have in the pathogenesis of atherosclerosis. METHODS: We examined immunohistochemically 20 normal carotid arteries and the carotid arteries of 86 patients (mean age, 68 years; range, 52 to 80 years) who underwent atherectomy for primary atherosclerosis. The expression of two genes, BCL2, which inhibits apoptosis, and BAX, which induces apoptosis, was examined and correlated to the presence of risk factors that included hypertension, smoking, hyperlipidemia, and diabetes mellitus. RESULTS: BAX expression was found in 26 of 86 cases (30%), and no immunoreactivity was found in the normal carotid specimens. BCL2 expression was not seen in any examined tissues (atherosclerotic or normal carotid arteries). Of the 26 patients who expressed the BAX gene, 22 were hypertensive (85%), and hypertension (>160/95 mm Hg) was present in 25 of 60 patients (41%) who did not express the BAX gene (p < 0.01). No significant correlation was found between the expression of the BAX gene and other risk factors (smoking, hyperlipidemia, diabetes mellitus) or presenting symptoms. CONCLUSIONS: In a significant number of stenosed carotid arteries (30%), we found no evidence of apoptosis suggested by the presence of BAX expression. Hypertension was more prevalent in those patients with BAX gene expression than in those patients without BAX gene expression. BCL2 expression, which inhibits apoptosis, was not found. Further study of this phenomenon may contribute to the discovery of new treatments for atherosclerosis.

Adolescent↗
PubMed1998

Putrescine administration reverses cadmium-associated inhibition of liver regeneration.

The liver is of central importance in the metabolism of essential and toxic metals such as cadmium. Cadmium pretreatment suppressed the liver regenerative response to partial hepatectomy, due to the inhibition of the enzymatic activity of thymidine kinase. Exogenous putrescine administration has been reported to stimulate liver regeneration in animal models of acute liver failure. The purpose of this study was to document whether the administration of this polyamine enhances the impaired regenerative capacity of hepatocytes in cadmium-pretreated partially hepatectomized rats. The intraperitoneal administration of putrescine (1 or 10 mg/kg body weight), at the time of surgery and at 4 and 8 hr postoperatively partly restored the suppressed hepatocyte deoxyribonucleic acid (DNA) biosynthesis and thymidine kinase activity in cadmium-pretreated partially hepatectomized rats. Mitotic activity and the percentage of hepatocytes positive for proliferating cell nuclear antigen nuclei were in accordance with the liver proliferative status. Our results showed that exogenous putrescine administration is able to improve diminished liver regeneration after partial hepatectomy in this animal model of acute hepatic injury.

Animals↗