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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

The metallothionein (MT) family is a class of low molecular weight, intracellular and cysteine-rich proteins presenting high affinity for metal ions. Although the members of this family were discovered nearly 40 years ago, their functional significance remains obscure. Four major MT isoforms, MT-1, MT-2, MT-3 and MT-4, have been identified in mammals. MTs are involved in many pathophysiological processes such as metal ion homeostasis and detoxification, protection against oxidative damage, cell proliferation and apoptosis, chemoresistance and radiotherapy resistance. MT isoforms have been shown to be involved in several aspects of the carcinogenic process, cancer development and progression. MT expression has been implicated as a transient response to any form of stress or injury providing cytoprotective action. Although MT participates in the carcinogenic process, its use as a potential marker of tumor differentiation or cell proliferation, or as a predictor of poor prognosis remains unclear. In the present review the involvement of MT in defense mechanisms to toxicity and in carcinogenicity is discussed.

The aim of this study was to examine glucocorticoid receptor (GR) immunohistochemical expression in colon cancer histopathological specimens and to correlate it with clinicopathological parameters, tumor proliferative capacity, cell cycle-related molecule expression, and patients' survival. Primary tumoral samples from 91 colon cancer patients were immunostained for the detection of GR, cyclins D1 and E, Rb protein (pRb), p16, p21, and Ki-67, using the streptavidin–biotin–peroxidase technique. GR expression was correlated with tumor histopathological characteristics and proliferative capacity, cell cycle-related molecule expression, and patients' survival. GR positivity was prominent in 44 of 91 (48%) colon cancer cases and was positively correlated with the expression of cell cycle-related molecules pRb (P = 0.008) and p16 (P = 0.002), while lack of correlation was noted with cyclins D1 and E and p21. GR expression was not correlated with tumor location, grade of differentiation, Dukes' stage, lymph node and liver metastasis, venous invasion, tumor proliferative capacity (evident by Ki-67-labeling status) and patient survival. Our findings support evidence for GR participation in the biological mechanisms underlying the carcinogenic evolution in the colon, implying the use of glucocorticoids as an adjuvant treatment for cell cycle modulation in colon cancer cells.

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.

Metallothioneins (MTs), are low molecular weight proteins, mainly implicated in metal ion detoxification. In the present study, we investigated the expression of hepatic MT in a rat model of injury and regeneration, induced by carbon tetrachloride (CCl(4)) administration. A single intraperitoneal injection of 1 ml CCl(4)/kg body weight was performed in male Wistar rats, killed at different time points post-administration. The enzymatic activities of aspartate and alanine aminotransferases in serum were determined, in addition to the liver histological findings, to estimate hepatotoxicity. The rate of tritiated thymidine incorporation into hepatic DNA, the enzymatic activity of thymidine kinase in liver tissue and the assessment of the mitotic index in hepatocytes, were used as indices of regeneration. MT was detected immunohistochemically in liver tissue sections. CCl(4) administration caused severe hepatic injury, followed by regeneration. MT expression became prominent as early as 12 h after the administration of CCl(4), in the nuclei of hepatocytes, while at 24 and 36 h intense cytoplasmic staining for MT appeared in the hepatocytes in the vicinity of necrotic areas. The peak of hepatocyte proliferative capacity, occurring at 48 h post-CCl(4) administration coincides with the maximum nuclear and cytoplasmic MT expression. At further time points MT expression presented a decreasing trend. Induction of MT expression was observed in the liver after a single administration of CCl(4), being more prominent at the time of maximum hepatocellular proliferation, participating actively in the replication of hepatocytes.

This investigation establishes the venous communication between the gastrocnemius muscle heads. Fourteen fresh (with the exception of one) cadaveric specimens were examined. Anastomotic veins were dissected along the raphe after perfusion of each muscle with 0.1 % methylene blue solution. A distally based musculocutaneous perforating vein of the medial head was the site of perfusion in 13 specimens, whereas one specimen received injection through the accompanying vein of the medial sural cutaneous nerve. Additional perfusion of dye from different sites was required in two specimens. Communicating veins were dissected in all 14 muscles. Direct anastomotic veins were detected in eight specimens; whereas in six the accompanying vein of the medial sural cutaneous nerve that had been included proved to be the intermediate pathway of venous communication between the muscle heads. Obstructive valves were encountered in most cases; nevertheless anastomotic veins were always recognized. The role of valves and the clinical implications are discussed.

Cells of the ciliated protozoon Tetrahymena pyriformis strain W, grown in a peptone-yeast medium, usually contain many phagocytic vacuoles. The phagocytic activity of this protozoon was studied in vivo using heat-inactivated yeast stained with carmine after exposing the cultures for 1 hour to different doses of cocaine hydrochloride or cocaine freebase (crack) (0.5, 1 or 2 mg/100 ml of protozoan culture).The number of vacuoles formed indicated the phagocytic activity. Cocaine hydrochloride and crack caused a decrease of the phagocytic activity of the protozoon (p < 0.05) when compared to the control cultures. Furthermore, the two chemical forms of cocaine, salt and free-base respectively, caused quantitatively different effects on the phagocytic activity. Crack produced an extensive decrease in phagocytosis, compared to equal concentrations of cocaine hydrochloride. These results suggest a possible relationship between cocaine abuse and the suppression of phagocytosis that may contribute to the impairment of immunity in drug misusers.

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.

The three major cannabinoids, Δ 9 -tetrahydrocannabinol (Δ 9 -THC), cannabidiol (CBD) and cannabinol (CBN) were identified and determined quantitatively using a GCD (GC–EI) instrument, in samples of illicit herbal cannabis, seized by Customs and Police authorities in two areas of Greece (Ipiros and Lakonia) during 1996. These samples were sent by the above authorities to the Department of Forensic Medicine and Toxicology, University of Athens, for forensic chemical analysis. The cannabinoid content of these samples led to the classification of cannabis into two chemical phenotypes and to the differentiation of resinous and textile plants by using three different classification indexes. The cannabinoid content of cannabis plants is of forensic value in determining the geographical origin of cannabis samples, since it can be used for their classification, allocating this way the area of cultivation of the relative plants. The forensic aspects of cannabis classification are discussed.

In drug overdoses, treatment with activated charcoal is frequently used because of its adsorptive properties. Recently, whole-bowel irrigation with polyethylene glycol-electrolyte lavage solution has been used as a gastrointestinal decontamination procedure for ingestions of toxins not well adsorbed to activated charcoal and for toxins with a delayed absorption phase, although well adsorbed to activated charcoal. While a combined approach using activated charcoal and whole-bowel irrigation could theoretically enhance the efficacy of both modalities, this improvement remains speculative, since data demonstrating its clinical advantage in overdose treatment are lacking. Fluoxetine, a selective serotonin uptake inhibitor, is one of the most frequently prescribed antidepressants. Fluoxetine is well adsorbed onto activated charcoal. This in vitro investigation was undertaken to study: a) the effect of polyethylene glycol, as well as polyethylene glycol-electrolyte lavage solution, on the adsorption of fluoxetine to laboratory grade-activated charcoal and a commercial activated charcoal formulation (Carbomix powder) in simulated gastric (pH= 1.2) and intestinal (pH=7.2) fluid environment; b) whether the order of polyethylene glycol-electrolyte lavage solution addition would have any effect on the adsorption of fluoxetine to activated charcoal.Adsorption of fluoxetine to charcoal in the presence of polyethylene glycol was examined: a) by the simultaneous addition of polyethylene glycol and charcoal to fluoxetine solution and b) by the addition of charcoal to fluoxetine solution and subsequent addition of polyethylene glycol. In both cases, the slurries were incubated at 37 degrees C for 1 hour and filtered. Free fluoxetine concentration was determined in the diluted filtrate by a reversed-phase high-performance liquid chromatography method.The amount of fluoxetine adsorbed to activated charcoal (or Carbomix) was dramatically decreased at gastric and intestinal pH by the presence of polyethylene glycol or polyethylene glycol-electrolyte lavage solution added either concurrently or sequentially to activated charcoal.In cases of fluoxetine overdose, administration of activated charcoal is recommended, while a combined approach using activated charcoal and whole-bowel irrigation with polyethylene glycol-electrolyte lavage solution is not recommended since it causes a significant desorption of the drug from activated charcoal.

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.

Six new amphetamine-like molecules (2-[2,3-dihydro-4 H-1,4-benzoxazine-4-yl]-1-methyl-2-[l-methyl-2-phenylethylamino] ethanamines) were synthesised and their physico-chemical behaviour was studied. The log P values (index of lipophilicity) of the derivatives were calculated according to Rekker's fragmental system. One derivative representative of each series (C-5508 and C-5512) was selected, and their biological effects on the phagocytic ability of the protozoan, Tetrahymena pyriformis, were studied as a basic functional test for an amphetamine-like action. Furthermore, the action of both derivatives when administered concomitantly with haloperidol was also investigated. The data indicate that both derivatives significantly increased the phagocytic ability of the protozoan (p < 0.001), presumably via an alternative pathway to that of one of the dopamine monoaminergic pools. The administration of haloperidol significantly suppressed phagocytosis (p < 0.001). However, cultures exposed to the derivatives and to haloperidol indicated quantitatively different reactions. The lipophilic behaviours of the derivatives provide & possible explanation for such distinct effects.

The effects of human growth hormone (hGH) therapy on biochemical markers of bone metabolism were studied in 17 children (10 boys and 7 girls, aged 3.7-13.1 years old) with idiopathic GH deficiency, before and 1 and 6 months after GH therapy (0.5 0.7 IU/kg weekly SC). Serum levels of calcium, phosphate, alkaline phosphatase osteocalcin, parathyroid hormone, 1,25 dihydroxyvitamin D, insulin-like growth factor I (IGF-I) and renal phosphate per 100 ml glomerular filtrate (TPO4/GFR) were assessed. During therapy with hGH a significant decrease of serum calcium levels and increases of phosphate, osteocalcin, parathyroid hormone 1,25 dihydroxyvitamin D and IGF-I were observed. TPO4/GFR was also significantly increased. Growth response (increment in HV) was positively related with changes in alkaline phosphatase and IGF-I levels after 6 months of hGH therapy. There was also a significant positive correlation between increment in HV and increment in TPO4/GFR after 1 month of GH therapy, whereas no correlation between HV and changes in osteocalcin levels was found.GH treatment significantly influences mineral metabolism and the measurement of TPO4/ GFR after 1 month of GH therapy may serve as a useful predictor of growth response to hGH therapy in GH-deficient children.

Blood alcohol concentrations (BACs) are regularly used as evidence in criminal and civil litigation. The forensic toxicologist is frequently asked, during his routine work or during court testimony, to give an expert opinion on the question as to whether alcohol concentrations measured in postmortem blood represent alcohol ingested prior to death or were formed postmortem [1–4]. The interpretation may be critical to the thorough investigation of different kind of forensic cases, like driving under influence, homicides etc. When putrefaction has occurred, one must exercise extreme caution in interpreting alcohol levels obtained by analysis of such putrid samples. During the putrefactive process alcohol may be lost due to evaporation or produced by microbial activity, primarily on glucose and to a lesser extent on lactate, amino or fatty acids [5,6].

The liver is of central importance in the metabolism of essential and toxic metals such as cadmium (Cd). Cd pretreatment suppressed the regenerative capacity of hepatocytes, which normally occurs 24 hr after partial hepatectomy, due to the inhibition of the activity of the enzyme thymidine kinase. The effect of hepatic stimulator substance (HSS) administration (10, 20, and 40 mg protein/kg body weight) on hepatocyte proliferation was investigated in Cd-pretreated partially hepatectomized rats. HSS administration partly restored the suppressed hepatocyte DNA biosynthesis in Cd-pretreated partially hepatectomized rats. The hepatocyte mitotic activity and the percentage of proliferating cell nuclear antigen-positive nuclei were in accordance with the liver proliferative status. The administration of HSS did not affect in a statistically significant manner the activity of the enzyme thymidine kinase in Cd-pretreated partially hepatectomized rats. It is suggested that the administration of HSS ameliorates the diminished hepatocyte regenerative response to partial hepatectomy in this model of acute liver injury, due to Cd intoxication.

The effect of hepatic stimulator substance (HSS) administration on cadmium (Cd) induced hepatotoxicity was studied in the rat. HSS was extracted from the liver of weanling rats (Hepatology 1988; 7: 100–106). Rats were injected with 2.5 mg CdCl 2 /kg body weight to induce acute liver injury, evaluated 24 h later. Serum enzyme activities of alanine amino-transferase (ALT), aspartate aminotransferase (AST) and histological parameters were used for the estimation of Cd-induced hepatotoxicity. HSS, at doses of 10, 20 and 40 mg protein/kg body weight, injected 10 h after Cd administration, caused dose-dependent decrease of hepatic injury. HSS suppressed the elevation of AST and ALT induced by Cd, in a dose-dependent manner. Liver histological changes indicated that HSS reduced the severity of hepatic lesion induced by Cd administration and reversed Cd-induced hepatotoxicity. In conclusion, our results suggest that HSS administration protects the liver against Cd-induced injury.

To elucidate possible causes of recurrences after transurethral resection of the prostate (TURP), we performed an anatomical study of the prostate in 37 cadavers. The anatomical study showed that a significant proportion of the prostatic adenoma laid below the verumontanum. This proportion in relation to the total prostatic length varied from 8.33 to 44.44%, while in relation to the weight it varied from 2.08 to 36.84%. After transurethral resection of the prostatic adenoma, part of the apical lobes below the verumontanum remains intact deliberately to secure continence. These adenomatous tissues left behind create the problem of the residual apical lobe. Recent reports in the literature have shown a higher incidence of prostatic adenomatous recurrences following TURP than after open prostatectomy. From our study and from an extended search in the literature, it seems that a possible reason for adenomatous recurrences can be due to the remaining residual apical lobes that are left behind after TURP, providing that the resection had been complete.

A simple and rapid reversed-phase liquid chromatographic method for the determination of amitriptyline and nortriptyline in plasma is described. Protriptyline was used as internal standard. Plasma samples were extracted from alkaline pH with hexane-isoamylalcohol 98:2 v/v for 60 sec on a vortex apparatus. The organic phase was back extracted with HCl 0.1N and the aqueous phase was injected directly and monitored at 240nm. Samples were chromatographed on a 5 μm Kromasil 100-C8 column (25 cm × 4 mm i.d) using acetonitrile/0.04M KH2PO4 40:60 v/v as the mobile phase. The lower limit of detection was 5 ng/ml for amitriptyline and nortriptyline while the lower limit of quantification was 10 ng/ml for both compounds. Peak height and plasma amitriptyline or nortriptyline concentrations were linearly related from 25 to 300 ng/ml. No potential sources of interference have been identified. The methodology was used to monitor plasma amitriptyline or nortriptyline concentrations in patients receiving therapeu...

An assay for computerized scoring of the DNA content of the protozoan Tetrahymena pyriformis has been used for the detection of toxic responses to cocaine, since DNA is responsible for the replication of the genetic material and also reflects closely the number of chromosomes in the nucleus. Thus, doubling of the number of chromosomes in a cell will also correspond to doubling of the DNA content and of the nuclear volume. Two chemical forms of cocaine were used, cocaine hydrochloride and cocaine freebase (crack), at two doses of 1 and 2 mg per 100 ml of protozoan culture, respectively. Image analysis of the protozoan nucleus patterns revealed a rapid stimulating effect on the DNA content for both cocaine hydrochloride and freebase after 1 h of incubation. However, after 2 h of treatment a reduction, although not statistically significant, of the DNA content of the protozoan was observed. These observations were further correlated with the phagocytic activity of the protozoan cultures. This paper provides some possible explanations of the toxic effects of cocaine on this particular cell model.

Radioimmunoassays specific for the N and C termini of human prothymosin alpha and the N terminus of human parathymosin alpha were employed for the measurement of the levels of alpha-thymosins in human thymus, spleen, and liver during normal growth and intestine and breast in malignant growth. A differential expression of the two alpha-thymosins was observed in thymus (prothymosin alpha-rich) and liver (parathymosin alpha-rich). A decline in the levels of both alpha-thymosins was found with age, with prothymosin alpha in thymus showing the sharpest change (15- to 30-fold). The levels of both alpha-thymosins were higher in malignant tissues as compared with healthy ones. In breast cancer, in particular, the mean increase for prothymosin alpha and parathymosin alpha was 17.9- and 11.5-fold, respectively. The major crossreactive material was characterized in all cases as intact prothymosin alpha and parathymosin alpha. These results suggest an in vivo relationship of the expression of alpha-thymosins with the human tissue cell proliferation activity.

Autopsy was performed on 49 male cadavers and the entire course of the left testicular vein (LTV) was studied. The testicular venous pathway was divided into four levels: scrotal, inguinal, pelvic, and lumbar. At the scrotal level, many small testicular veins constituting the pampiniform plexus showed various anastomoses with the cremasteric and vasal veins. At the inguinal and pelvic level, 4-12 and 2-8 LTVs were recognized, respectively. At the pelvic level, absence of valves was seen in 33% of the cases. At the lumbar level, 1-5 LTVs were observed and were mainly anastomosed with the retroperitoneal, ureteral, and kidney capsular veins. Absence of valves at the lumbar level was seen in 37% of the cases. In 11 cases, the valves that were present were incompetent. The presence of more than one LTV at the lumbar level indicates the necessity for attentive identification of all of the testicular veins during surgical treatment of varicocele. Arch Androl

The Rm values of 32 compounds, derivatives of benzoic acid, were determined by reversed-phase thin layer chromatography (RP-TLC). The logarithm of the capacity factor, log k', of the same compounds was studied with reversed-phase high performance liquid chromatography (RP-HPLC). The lipophilicity was calculated according to the fragmental methods of Rekker and of Leo-Hansch and was compared with the experimental values of Rm and the log k'. The comparison shows that the Rekker method gives a better description of lipophilicity than that of the Leo-Hansch method.

The attitudes of the Greeks, a Mediterranean population, to the issue of telling the truth to the patient have been studied. There is no clear answer to the question: 'Do the Greeks wish to be informed of the nature of their illness?'. The answer is: 'It depends'. It depends on age, education, family status, occupation, place of birth and residence and on whether or not they are religious people. However, it does not depend on their sex--men and women have similar reactions to the issue of truth-telling. Although the present study shows lower percentages of those who wish to know the truth than studies on other populations, the conclusion is that, emphasising the need for good communication between doctors and patients, doctors should not lie, but should disclose to their patients the part of the truth they are ready to accept.