TOXICOLOGY

Author: ISEA FERNÁNDEZ GERARDO.
Year: 2003.
University: COMPLUTENSE DE MADRID [More theses of this university] [www.ucm.es].
Place of defense: FACULTAD DE VETERINARIA.
Place of preparation: FACULTAD DE VETERINARIA.

Summary: The fluoroquinolone second generation pefloxacina, is a derivative of the acid piperazino, carboxylic, initially developed in human medicine for oral and parenteral use and potential use in veterinary medicine presents good activity against Gram-negative bacteria, including most of the species enterobacteria and Haemophilus genres, and Neisseria Legionella, and also significantly more active than other fluoroquinolones compared with Gram-positive bacteria such as Staphylococcus aureus and Staphylococcus epidermidis. In men, pefloxacina provides good absorption with high bioavailability and prolonged elimination half-life in plasma; low protein binding; high volume of distribution with excellent tissue distribution and penetration in body fluids. This antimicrobial is widely metabolized, and its major metabolites the N-demetil-pefloxacina or norfloxacin and N-oxido-pefloxacina. Available information on the pharmacokinetics of pefloxacina in animal species is scarce, and is not described in literature pharmacokinetic behavior of the perfloxacina in broilers, so the objective of this work includes: 1 - The study of the pharmacokinetic behavior the pefloxacina after oral and intravenous administration of 10 mg pefloxacina / kg bodyweight 2 - The study of the pharmacokinetic behavior of metabolite N-demetil-pefloxacina (norfloxacin) after oral and intravenous administration of 10 mg pefloxacina / kg bodyweight EXPERIMENTAL DESIGN are used 16 broilers Ross of 2.5 kg bodyweight, clinically healthy, divided into two groups. After treatment, blood samples were taken to 10.20 and 30 minutes, and 1,2,4,6,8,12, and 24 hours. In each animal was determined concentration of the compound pefloxacina and its metabolite norfloxacin following, with minor modifications, the analytical method of liquid chromatography with detection fluorimetría previously described by Montay and Tassel (1985), validated analytical method in the laboratory with the criteria linearity, resproductibilidad, repeatability, limits of detection and quantification. FINDINGS AND CONCLUSIONS Plasma concentrations of pefloxacina found experimentally in broilers following intravenous and oral administration of 10 mg / kg bodyweight, were adjusted properly to an open model bicompartimental. Following intravenous administration the pefloxacina is slowly eliminated from plasma (t1/2beta = 8.44 h, MRT = 7.94 h, CL 0.19 L / h / kg), and an extensive distribution [K12/K21 = 1.58 you (area) = 2.36 L / kg; you (ss) = 1.54 L / kg]. Metabolite N-demetil-pefloxacina is also slowly eliminated from plasma (t1/2beta = 8.02 h, MRT = 7.54 h), and has a wide distribution (K12/K21 = 2.84). After oral administration, pefloxacina is absorbed rapidly and extensively (t1/2alfa = 0.87 h, F = 70%; MAT = 5.63 h), is slowly eliminated from plasma (t1/2beta = 13.18 h, CL = 0, 19 L / h / kg; MRT = 13.57 h), and has extensive tissue distribution [K12/K21 = 1.51; you (area) = 3.55 L / kg]. The fluoroquinolone pefloxacina is biotransformation in the body, detected the metabolite N-demetil-pefloxacina that after oral administration presetó to 5% of plasma concentrations of the compound unchanged. In broilers, the oral dose of 10mg pefloxacina / kg bodyweight, provides high therapeutic plasma concentrations in front of the main pathogens that cause common infections in birds. The plasma Cmax achieved was 4.02 ug / ml in a Tmax = 2.01 h, plasma concentrations greater than 0.81 ug / ml and 0.36 ug / ml persitieron at 12h and 24h post. The oral dose of 10 mg pjefloxacina / kg bodyweight, provides clearly values of the indices PK / PD, Cmax / WCC increased 10 and AUC24/CMI larger 125, taking a calculated value of CMI 90 8 of 0.3 or 2a6 g / ml, a value that includes common bacterial pathogens in birds. It is suggested that a system of oral dosing of 10 mg pefloxacina / kg bodyweight, every 24 hours for 3-4 days, it might be of therapeutic value compared to most of the common infections in broiler chickens.

Author: OROPESA JIMÉNEZ ANA LOURDES.
Year: 2003.
University: EXTREMADURA [More theses of this university] [www.unex.es].
Place of defense: FACULTAD DE VETERINARIA.
Place of preparation: FAC. VETERINARIA.

Summary: Faced with the impact that had and still finding residues of the herbicide triazínico simazine in natural and drinking water in various localities of the province of Badajoz (Extremadura), has conducted a study on the impact of the herbicide has resulted in piscifauna native choosing as a species bioindicadora common carp (Cyprinus carpio). To this end it has been determined a battery of biomarkers of biotransformation of toxic (EROD), regulating the activity of the nervous system (AChE), energy metabolism (ATP glycogen, glucose, lactate, proteins and LDH), both tissue as plasma or blood, haematological parameters (hermatocrito, hemoglobin, CHCM) as well as histological studies complementary. All this done through a field trial (sampling of two reservoirs contaminated fish and one control) and an experience lab 90 days in which tents were exposed to a concentration of 45 ug simazine / l (10 times higher than detected in the natural aquatic environment). Contrasting findings in tents who lived in the marshes contaminated with the results obtained in laboratory experience, we can conclude that the levels of simazine present in natural waters from pollution in the episode occurred in late 1997 did not cause biochemical or physiological changes major carp exposed. The pathological changes observed in exposed tents have been regarded as nonspecific and little relevance in terms of their seriousness, not seriously affecting the functionality of the hepatopancreas, kidney or gills, as they tend to refer to the end of the exposure period.

Author: QUINTELA JORGE OSCAR.
Year: 2004.
University: SANTIAGO DE COMPOSTELA [More theses of this university] [www.usc.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: FACULTAD DE MEDICINA.

Summary: Benzodiazepines are a large group of psychoactive drugs, which are widely used for their versatile applications clinics (treatment of insomnia and anxiety, anticonvulsants, muscle relaxants, antidepressants, panic attacks, etc.) and for his wide margin of safety, which has detenminado which have replaced the barbiturates in many of their traditional applications. The toxicological significance of benzodiazepines stems from several factors: 1) .- On the one hand, the broad prescription coupled with the same psychological profile of patients who habitually consume determines the substances that are most commonly involved in clinical poisoning in our midst after ethyl alcohol. While these poisonings often do not take seriously, in cases where drugs are associated with other CNS depressants such as alcohol, the clinical situation can become very committed. 2) .- Secondly benzodiazepines affect to some degree to certain motor skills and determine that those subjects who handle motor vehicles having an added risk of accidents due to this affectation; it has been determined that within the substances at this time being investigated for his involvement in road traffic are also alcohol and drug prescription of these drugs. At this time there is a project at the European level (ROSITA), which evaluates various devices to detect drugs and benzodiazepines in saliva of drivers. 3) .- Finally, the use of benzodiazepines from the toxicological point of view is taking on new dimensions with their application to what we might call late "criminals" in the sense that they cause anterograde amnesia is being tapped for certain individuals to commit sexual assault on its victims in a manner with impunity, a phenomenon which has also been called "chemical submission." Because, then, the obvious toxicological significance of these substances and the need to make the determination of the same biological means as saliva, or in circumstances where the plasma concentrations can be expected to be very low (for submission chemistry) you must have a sufficiently sensitive analytical method, as well as reliable for the determination of the same. The experimental work has been guided precisely to achieve these goals can be summarized as follows: 1 .- It has developed an analytical method for determining 9 benzodiazepines oral fluid and plasma: Benzodiazepines have been analyzed: Midazolam , Tetrazepam, Bromazepam, Alprazolam, Triazolam, Lorazepam, Flunitrazepam, Diazepam, and Lormetazepam. The biological samples (0.5 mL) have been subjected to a liquid to liquid extraction Eter Dietilico, prior to analysis. The instrumentation used for the analysis consisted of: Cromatógrafo fluid Alliance THT, Waters 2795 and Mass Spectrometer ZMD 2000 (Waters-Micromass), using an interface ionizaci6n at atmospheric pressure using electrospray. The validation parameters of the method (selectivity, accuracy, precision, recovery and calibration curve) have been within the criteria established by the FDA for all benzodiazepines analyzed. The detection limits have been obtained from 0.5 ng / mL for plasma and 0.1 ng / mL for oral fluid, which corroborates the sensitivity of the technique. 2 .- The validated method has been applied to actual cases (73) of plasma from patients with acute intoxication by benzodiazepines, or forensic cases where these drugs were present. Notably this study that benzodiazepine most frequently found in the samples tested has been the alprazolam, with a to 8 to porce 64th ntaje case the association of two or even three benzodicacepinas in the same sample. The method was applied to samples from a kinetic study conducted in patients undergoing chronic treatment with benzodiazepines, patients treated with a single dose midazolam (surgery) or continuous infusion and healthy volunteers to those who were administered a single dose a benzodiazepine. The purpose of this test was to make the study of the correlation between plasma concentrations and oral fluid, although the limited number of cases as well as the absence of a rigid protocol for sampling, have made it impossible to obtain conclusive data. 3 .- Finally, it has been applied to liquid chromatography coupled with mass spectrometry in tandem for the diagnosis of chemical submission by benzodiazepines. This work has been done in France, particularly in the Service de Pharmacologie du Center Hospitaleur Universitaire de Limoges, under the direction of Professor Marquet. In this case the analytical method has been applied to urine samples, reaching limits of detection of 20 pg / mL, and samples of hair.

Author: BARTOLOMÉ CAMACHO M. CARMEN.
Year: 2004.
University: COMPLUTENSE DE MADRID [More theses of this university] [www.ucm.es].
Place of defense: FACULTAD DE VETERINARIA.
Place of preparation: FACULTAD DE VETERINARIA.

Summary: It has valued the toxicological risk posed by environmental presence of different biocides used in cleaning desinfeción of cooling towers, in discharges from pipes sanitation on estuarine environments. This has been used as a biosensor to Artemia franciscana, crustacean in aquatic environments with high salt, which consitutye an essential element in the food chain of estuarine ecosystems. This research work has been raised in response to achieve different objectives, such as optimizing the model of statistical analysis used in the tratameinto on the results, assessing the acute toxicity of disinfectants selected on larvae of Artemia 24, 48 Y72 hours of life, the study of inhibiting the ability fototáctica that could cause these compounds on larvae Artemia tiveness of 24 hours, and finally the valuation of the bioaccumulation potential of these compounds or those dervidados its transformation into the aquatic environment in the tissues of these organisms. The compounds were selected chloride tetrakis (hydroxymethyl) fosfonio, trichloroisocyanuric acid, benzalkonium chloride and sodium bromide. Regarding the comparison of statistical methods and Probit Exponential Growth, the results demonstrated the appropriateness of use of the latter for toxicity testing, because even if the results did not show statistically significant differences, the best fit of data on the distribution of response obtained by the method of Exponential Growth is advisable use. The results of acute toxicity studies showed that both the chloride tetrakis (hydroxymethyl) fosofonio as trichloroisocyanuric acid and benzalkonium chloride behave as extremely toxic larvae on Artemia, 24, 48 Y72 hours of age, when they are evaluated through acute toxicity test. The sodium bromide has proved to be a non-toxic compound, where the tests were carried acute toxicity compared with larvae Artemia of 24 hours of age. However, Artemia larval stages of 48 and 72 hours of life, these same toxicity tests showed that the sodium bromide behaves as a very toxic. The comparative study on the toxic effects of acute type produced on the various larval stages, as opposed to the four compounds biocides tested, shows that there is an increase in sensitivity of larvae Artemia according increases their lifetime, being the most sensitive larvae 72 hours of age than those of 48 hours, and they in turn more sensitive than those of 24 hours of life. However, it does not appear minds significant statistical differences between larvae 24 and 48 hours of age when they are exposed to chloride tetrakis (hydroxymethyl) fosofonio. Regarding alos tests subletalidad, the four compounds tested biocides have the power to inhibit the ability fototáctica of larvae Artemia of 24 hours of age, when they are exposed to sublethal concentrations of each compound tested. This effect has been obtained at concentrations between 1 / 30 and 1 / 60 of the CLso, depending on the biocide compound tested. Finally, the studies revealed that bioconcentration values accumulation on Artemia larvae, it is 8 to Virginia 38e post parent or major metabolites, both chloride tetrakis (hydroxymethyl) fofonio as trichloroisocyanuric acid or sodium bromide, none of the three compounds poses an environmental risk in terms of the phenomenon of bioaccumulation. However, it is necessary to take into account the value of BCF = 93.75 obtained for exposures to chloride tetrakis (hydroxymethyl) fosfonio because it encuentramuypróximoal limit value of 100 considered at least potentially dangerous.

Author: PITA PITA RENÉ.
Year: 2004.
University: COMPLUTENSE DE MADRID [More theses of this university] [www.ucm.es].
Place of defense: FACULTAD DE FARMACIA.
Place of preparation: DPTO. DE TOXICOLOGÍA, FACULTAD DE VETERINARIA.

Summary: The pesticide fipronil is a relatively recent discovery and commercialization serving as a potent blocker of the recipients GABAérgicos associated with chloride ion channels, greater selectivity on the recipients of insects on receptors of mammals. However, the possible existence of other neurotoxic mechanisms of action of fipronil in mammals has not been studied. Signs of poisoning include fipronil in mammals anorexia, lethargy and seizures clónico-tónicas. It is difficult to explain the whole spectrum of the neurotoxic activity of fipronil simply in terms of a mechanism GABAérgico. Since many observations show that the systems catecolaminérgico and serotonin are involved in processes convulsive, this research work is aimed at studying the possible alterations in these systems neurotransmitters monoaminérgicos in regions of the CNS in Wistar rats exposed to multiple doses of fipronil (5, 10 and 15 mg / kg bw / day for 5 days). The fipronil altered in the CNS levels of serotonin (5-HT) and its metabolite acid 5-hidroxi-3-indolacético (5-HIAA), as well as levels of dopamine (DA) and its metabolites acid 3 , 4-dihidroxifenilacético (DOPAC) and acid homovanílico (HVA).

Author: ANTÓN LEZCANO ROSARIO M..
Year: 2004.
University: COMPLUTENSE DE MADRID [More theses of this university] [www.ucm.es].
Place of defense: FACULTAD DE VETERINARIA.
Place of preparation: FACULTAD DE VETERINARIA , UCM..

Summary: The fluoroquinolone Fleroxacina is a drug broad spectrum of antimicrobial activity compared to species Gram negative and Gram positive anaerobic microorganisms. Fluoroquinolones are generally regarded as concentration-dependent bactericidal antimicrobials. The fleroxacina is acid 6.8 difluoro-l (2-fluoroetil) -1.4 dihidro-quinoleincarboxílico. The antibacterial action of the fl, eroxacina, is the result of four consecutive steps bacterial level: a) Transition of the molecule through the bacterial cell wall to reach the cytoplasm b) Inhibition of the enzyme DNA girasa c) Inhibition the synthesis of DNA and d) Induction SOS response at the level of the bacterial cell. The fleroxacina could be an effective agent for the treatment of type colibacilosis and salmonella infections in birds. The fleroxacina after oral administration undergoes extensive metabolism, metabolites N-demetil fleroxacina and N-oxide fleroxacina rapidly emerge in plasma. The purpose of this study was twofold: 1) the pharmacokinetic study fleroxacina after single dose administration of intravenous and oral 4mglkg pv In broilers and 2Â °) the study of distribution and tissue depletion of fleroxacina and its major metabolites after oral treatment 4mglkg pv During 4 days in broilers. Design: We used 34 broilers Ross of 2-2.5 kg of body weight, divided into 3 groups to perform: A. Pharmacokinetic Study after single intravenous dose of 4mglkg pv Of fleroxacina B. Pharmacokinetic Study after single oral dose of 4 mg / kg. Pv Of fleroxacina. C. Study depletion tissue after oral administration of 4mglkgldía of fleroxacina for 4 days after treatment, at different periods of time, blood samples were taken and target tissues: liver, kidney, muscle and skin + fat, and each animal was determined the concentration fleroxacina and its metabolites in samples collected following a methodology analytical liquid chromatography with detection fluorimétrica previously described by Heizmann et al., (1990). Results and conclusioues: The results show that the curves of tissue and plasma levels versus time conform to a model open bicompartimental. The plasma toxicokinetic parameters describing the phases of absorption, distribution and elimination of fleroxacina show that after oral administration is absorbed rapidly and broadly (tI/2a = 0.32 h), is being circulated and is eliminated more slowly (tIl2 = 7.45 htras oral administration and 5.63 h after intravenous administration). Plasma total body clearance was (CL = 0.28 L / h / kg). The fleroxacina is absorbed widely and quickly after oral administration, Cmax = 1.33 Ilglml a Tmax = 0.9 Ih. The oral bioavailability was about 45%. The tissue distribution study shows that fleroxacina is widely distributed in the body effective concentrations found in a range between 66.94 and 281.28 Ilg / kg in the tissues (in order of increasing skin + fat, muscle, liver and kidney after a day of withdrawal. tissue These concentrations slowly declined after 3 and 6 days waiting or retirement. Like the composite unchanged fleroxacina, metabolites N-demetil fleroxacina and N-oxide fleroxacina declined more rapidly after withdrawal of treatment. It that needs to be considered in conjunction with the metabolites unchanged compound as a marker residue.

Author: RÍOS INSUA ALBA.
Year: 2004.
University: COMPLUTENSE DE MADRID [More theses of this university] [www.ucm.es].
Place of defense: FACULTAD DE VETERINARIA.
Place of preparation: FACULTAD DE VETERINARIA.

Summary: The florfenicol is a synthetic antimicrobial compound belonging to the family of fenicoles. It is a derivative of fluoride thiamphenicol, with a pharmacological profile similar to that of the two other compounds from the same family and chloramphenicol thiamphenicol. Its structural differences with these compounds similar him two basic characteristics. On the one hand, does not produce discrasias blood grave and another is not likely to face the chloramphenicol acetyl transferase, thus improving its effectiveness and maintains front of all those microorganisms resistant to chloramphenicol (Enterobacterias, Haemophillus spp., Pasteurella spp.). Its mechanism of action is based on the inhibition of protein biosynthesis of the microorganism. The florfenicol is a synthetic broad-spectrum antibiotic, with a bacteriostatic behavior compared to most Gram-positive bacteria and Gramnegativas (aerobic and anaerobic) isolated in pets. In order to fill the vacuum created by the withdrawal of chloramphenicol and its spectrum of activity, florfenicol focused its development from the veterinary field. The first animal species for which was registered on florfenicol was bovine. In respiratory presents good absorption processes with high bioavailability and prolonged elimination half-life in plasma; high volume of distribution with excellent tissue distribution and penetration in body fluids. This antimicrobial is widely metabolized, and its major metabolite the florfenicol amine. There is information on the pharmacokinetics of florfenicol in other animal species: goats, sheep, equine, fish and poultry. Regarding broilers or broiler existing information is limited, and is not described in the literature depletion tissue residue florfenicol. Therefore, the objective of this work includes: 1) The study of the pharmacokinetic behavior of florfenicol after oral and intravenous administration of a single dose of 20 mg florfenicollkg pv 2) The study of distribution and depletion tissue florfenicol and its major metabolite florfenicol amine after oral administration of 20 mg florfenicol / kg bodyweight During three days. Design: We used 34 broilers Ross of 1,8-2,0 kg bodyweight Clinically healthy, divided into three groups. After treatment, blood samples were taken for 10, 20 and 30 minutes, and 1,2,4,6,8, 12Y24 hours. In each animal was determined concentration of the compound florfenicol and its metabolite florfenicol amine, the following analytical methodology of high resolution liquid chromatography with UV detection previously described by Adams et al. (1987), and with the conditions chromatography according to VARMA et al. (1986), validated analytical method in the laboratory with the criteria of linearity, reproducibility, repeatability, limits of detection and quantification. Results and conclusions: Concentrations plasmáticas-tiempo of florfenicol found experimentalmenteen broilers following intravenous and oral administration of 20 mg / kg bodyweight, were adjusted properly to an open model bicompartimental. Following intravenous administration the florfenicol is slowly eliminated from plasma (t1/2beta = 5.36 h, MRT = 5.29 h, CL 0.46 L / h / kg), and has a wide distribution [K12/K21 = 8, 86 you (area) = 3.39 Llkg; you (ss) = 2.34 Llkg]. after oral administration the florfenicol is absorbed rapidly and extensively (t1/2a = 016 h, F = 78%), is slowly eliminated from plasma ( tI / ~ Z = 8.17 h, CL = 0.42 Llhlkg; MRT = 8.26 h), Yposee broad tissue distribution [K12/K211 = 2.49; you (area) = 4.99 Llkg]. The florfenicolse biotransformaen chickens being the major metabolite florfenicol amine which is also slowly eliminated from plasma, (t1 / 2 beta = 9.04 h, MRT = 9.15 h), Yposee wide distribution (K12/K21 = 2.26 ). In the third group with 18 chickens, we studied the tissue distribution and depletion of florfenicol and metabo 8 lito flo 7f6 rfenicol amine, after oral administration of 20 mg florfenicol / kg pV During three days. The time intervals studied after administration of the last dose were 1, 5 Y7 days. The tissues were analyzed muscle, skin + fat, liver and kidney. For florfenicol, the day 1 after the last dose concentrations of all tissues gave levels above the maximum residue levels (MRLs) set for the florfenicol in birds. At 5 days after the last treatment, these levels declined significantly, and were below the MRLs set. For the metabolite florfenicol amine, day 1 were detected levels of all tissues. The qja 5 after the last dose levels are no longer detected in muscle. At 7 days after the last treatment these levels declined significantly, and were not detected in muscle or fat leather +. The waiting time after applying the statistical linear regression analysis to florfenicol and its metabolite florfenicol amine (advised by the European Medicines Agency) is 3.02 days for liver, 5.6 days for kidney, 7.56 days for muscle + fat and 8.36 skin. It is suggested that a system of oral dosing of 20 mg florfenicol / kg bodyweight Every 24 hours for 3 days, it might be of therapeutic value compared to most of the common infections in broiler chickens. And that a period of withdrawal, as a guidepost for food safety, 9 days ensure that the concentrations of residues (florfenicol + florfenicol amine) in all tissues were below the MRLs established plows this kind in the European Union.

Author: MOLINA LOPEZ ANA M..
Year: 2004.
University: CÓRDOBA [More theses of this university] [www.uco.es].
Place of defense: FACULTAD DE VETERINARIA.
Place of preparation: FACULTAD DE VETERINARIA.

Summary: Given the concern about data on the growing environmental pollution due to industrialization in today's society, and before the alarm for the health and social risks associated with exposure to cadmium (pollutants medioambientalesy food, jobs, snuff, etc.). , we decided to carry out this study to determine the potential impact at the CI2Cd administradoa low testicular doses over a long periodode time. It used 48 mice Swiss OF-1 male twelve weeks of age, which were given during 12 months 15 mg / l CI2Cd in drinking water. The sacrifices were performed after 1, 3, 6 and 12 months exposi.ción; resilience of the testis was considered in two groups after being exposed to cadmium for 3 and 6 months of "an ongoing, I was withdrawn for another 3 and 6 months, respectively. after slaughter by cervical dislocation, the testes were weighed and measured, and posteriormentese tomaronmuestras for toxicological analysis, and histopathological (structural and ultrastructural). The results showed that the concentration of cadmium increased progressively from testicular form linear time exposure. Anyway, the effects of the metal on the testis showed a strong dose of character so that was increasing as the exposure is prolonged. animals exposed to cadmium was observed: testicular atrophy, vascular lesions that changes in coloring outside decline in the fraction tissue occupied by the germinal epithelium and a consequent increase in tubular lights, degeneration of the architecture of the seminiferous tubules with degeneration and loss of cell components thereof there are thus a decrease in sperm production. addition at the interstitium was observed strong hyalinization of vessel walls, reaching produce edema, hemorrhage and interstitial thrombi. effects in the Leydig cells were also very tough: it was observed hypertrophy and anaplasia abundant images preneoplásicas that resulted in two cases in tumor interstitial (after 6 and 12 months of exposure, respectively). While the stereological and morphometric parameters showed some resilience of the affected tissue following removal of cadmium, alterations and degenerative form of nuclear showed quite persistent, suggesting that the risk carcinogénicose mantuvoaúntras withdrawal of cadmium

Author: GARCIA PEREZ ADOLFO GINES.
Year: 2004.
University: MIGUEL HERNÁNDEZ DE ELCHE [More theses of this university] [www.umh.es].
Place of defense: BIOLOGÍA APLICADA.
Place of preparation: BIOLOGÍA APLICADA.

Summary: The fenilvalerato esterases serum hen preinhibidas with paraoxon will resume completely by eliminating the inhibitory environment like that happened with the soluble fraction of peripheral nerve. This revival is spontaneous and progressively over time, discarding any kind of reversible inhibition. After applying different kinetic models they saw a process of revival and simultaneous inhibition, it was found that all the activity fenilvalerato esterase serum was reactivaba as a single component, being kr = 0,010 min-1 virtually identical to that obtained from the soluble fraction of nerve for one of its components. The fenilvalerato esterases serum hen, are inhibited from irreversibly and permanently by rr ¡jpafox not found recovery in activity after eliminating inhibitor half. By applying a model of a three-dimensional setting the kinetics of inhibition with mipafox, found that 80% of the activity fenilvalerato esterase serum is inhibited within a single component sensitive, as ki = 0,005 nM-1 min-1 deduction worth the IC50 (30 min 37 ° C) = 4.4 nM, three orders of magnitude lower than for the inhibition of NTE by the same compound. Due to the rapid spontaneous revival of fenilvalerato esterases serum after inhibition by paraoxon and sensitivity to inhibition constant mipafox, one might conclude the existence of an activity type NTE serum, resistant to inhibition by paraoxon and sensitive permanent to mipafox. The phenomenon of transient inhibition by paraoxon of fenilvalerato esterases of soluble fraction of peripheral nerve observed in vítro, was confirmed by the low inhibition that the compound produced in vivo, as well as the partial protection of dosing previous paraoxon causing inhibition by DFP these esterases soluble. The paraoxon is not a useful tool for discrimination esterases target of neurotoxicity and / or promote axonopatías in peripheral nerve or its potential biomarkers in serum. It is proposed and applied a new test activity fenilvalerato esterase in soluble fraction of nerve and serum, based on the differential sensitivity to the OP neuropathic model mipafox, defining the following activities and conditions: A activity in the absence of mipafox and represents the activity fenilvalerato esterase total activity M1, resistant to 30 nM of mipafox; activity M2, resistant to 1! -1Mde mipafox and activity M3, resistant to 1 mM mipafox. Along with measures such activities are defined and the same, the components obtained from their respective differences: A-M1, M1-M2, M2-M3 YA-M2. The PMSF, composite model promoter, is able to inhibit both in vitro and in vivo more than 70% of the activity fenilvalerato esterase resistant inducing compound mipafox (M2 and M3) of soluble fraction of nerve. By contrast the DFP, neuropathic model compound, which is administered at a dose promocionable (0.5 mg / kg sc) is not at all capable of inhibiting this activity fenilvalerato esterase resistant mipafox of soluble fraction of peripheral nerve. Dose weakly promoting PMSF (1 and 10 mg / kg sc) are only capable of both a 40% inhibition of the activity fenilvalerato esterase resistant mipafox (M2) of soluble fraction of nerve, whereas the standard dose promoter ( 120 mg / kg sc) is able to inhibit more than 70% for this activity. The great sensitivity to the compound DFP model of neuropathic activities fenilvalerato esterase soluble nerve is reflected in the values which have animals who were administered a dose neuronopathic of 0.5 mg / kg sc, and sacrificed only 10 minutes after dosing, which prese 8 ntan a 87b total inhibition of the activity fenilvalerato esterase sensitive mípafox (A-M2) while for these animals, the activity NTE particulate fraction of the same fabric is not inhibited, appearing only 40% inhibition of NTE activity in the brain. The sulfonil fluoride FHP administered following a dose promocionable of DFP and before a dose promoter PMSF, is not capable of protecting the phenomenon of advocacy. Therefore, fenilvalerato esterases more sensitive to mipafox (A-M1 and M1-M2) completely inhibited by FHP, can be excluded as a target of the phenomenon promotion neuropathy. It has found a linear correlation between moderate activities fenilvalerato esterase A M1 YM2 the soluble fraction of peripheral nerve and activity fenilvalerato esterase M1 serum with a value of the correlation coefficient (R2) of about 0.5 and a high significance Bilateral for the linear relation (P MINOR 0,001). The test method proposed in this report has revealed in the peripheral nervous system activity carboxitesterasa soluble, so far considered irrelevant by its sensitivity to the compound not neuropathic paraoxon, extremely sensitive both compounds inducers as promoters of neuropathy. The possible role of such toxicological esterases in the adverse effects resulting from prolonged exposure to doses apparently subneuropáticas compounds organofosfarados, and the precise identification of the molecular target of the promotion will require additional in vivo studies with different dose levels of both drivers and promoters and molecular collisions on fractions esterásicas toxicologically relevant.

Author: PIZARRO LOZANO MARIA NIEVES.
Year: 2004.
University: POMPEU FABRA [More theses of this university] [www.upf.edu].
Place of defense: DEPARTAMENTO DE CIENCIAS EXPERIMENTALES Y DE LA SALUD.
Place of preparation: DEPARTAMENTO DE CIENCIAS EXPERIMENTALES Y DE LA SALUD.

Summary: The MDMA is headed series of entactógenos. Its consumption is associated with episodes of acute toxicity and toxic effects nuerodegenerativos on the central nervous system in the medium / long term. It postulates that his bioinactivación metabolic could have a very important role in the development of neurotoxicity. The molecule MDAM have a center estereogénico (preserved in its metabólitos), which makes exists as a pair of enantiomers (R, S). It consumes as racemate but the enantiomers have pharmacological effects and pharmacokinetic profiles differentiated. With regard to pharmacokinetics, is influenced by cleansing metabolic enantioselectiva (via CYP2D6) and autoinhibible. In this thesis explores the enantioselectividad of metabolic cleansing of MDMA in consumer recreational participants in a clinical trial (dosage: 100 mg). The study includes the identification of the enantiomers of MDMA and its metabolites in biological fluids. It took the synthesis of reference material enantioméricamente enriched (MDAMa and metabolites) and the development of methodology for the analysis enantioselectivo and diastereoselectivo of compounds. We studied the enantioselectividad metabolism of MDMA until 48 hours after administration, obtaining relationships (R) -MDMA increased 1 and on the rise, while the relations of the major metabolites were practically constant and close to 1. This would be linked to the inhibition of metabolism of CYP2D6 and the participation of other enzymes not enantioselectivos.

Author: GONZÁLEZ CARRACEDO ANIOAL.
Year: 2004.
University: VIGO [More theses of this university] [www.uvigo.es].
Place of defense: FACULTAD DE CIENCIAS OURENSE.
Place of preparation: AREA TOXICOLOGÍA FACULTAD DE CIENCIAS OURENSE.

Summary: Cadmium is a neuroendocrine disruptive. In addition, like many other xenobiotics, a cronotoxicidad important. Moreover, the physiological functions are governed according patterns cricadianos and circaestacionales, so that cadmium could exert toxicity through changes in the activity of the endogenous circadian clock systems monoaminérgicos brain and shaft hipofisario-testicular. Furthermore, these changes would be different depending on the time of year and the stock or breed of animal experimentation, and their age. The objective of this study is to evaluate the changes that induce cadmium in the shaft hipotalámico-hipofisario-testicular and striped in aged male rats of the Wistar strain from the point of view cronobiológico. To achieve this goal has studied the circadian rhythm of the concentration of norepinephrine, dopamine and serotonin, and the metabolism of these last two monoaminas in the hypothalamus, pituitary and testes. In this paper we have used 288 male rats of the Wistar strain; 114 adult rats youth, two months of life, and 144 rats aged from 18 months. Cadmium has been administered to a group of 72 adult rats and 72 rats aged, in the form of cadmium chloride (CdCl2) dissolved in their drinking water, at a dose of 25 ppm CdCl2 for 30 days. In other 144 rats (72 adults and 72 aged) has been administered drinking water supply from the Faculty and use as controls of the experiment. The animals were sacrificed at the end of treatment in subgroups of twelve rats every 4 hours throughout the day. Have been determined by HPLC with electrochemical detection of monoaminas and their metabolites. Plasma levels of LH and testorerona were determined by radioimmunoassay, and the accumulation of the metal has been determined by atomic absorption spectrometry. In view of the results it may be concluded that cadmium is a disturbing neuroendocrine that presents a cronotoxicidad circadiana at neuroquímico and in the axis player, toxicity different in adult and aged rats under the strain of animal and the annual station, and that can not be explained by the degree of retention of the metal.

Author: LÓPEZ GUARNIDO OLGA.
Year: 2004.
University: GRANADA [More theses of this university] [www.ugr.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: FACULTAD DE MEDICINA.

Summary: Several experimental and epidemiological studies have found conflicting results regarding the behavior of various antioxidant enzymes involved in oxidative stress generated by exposure to different types of pesticides. In this paper we have studied the enzymatic activities superóxido-dismutasa (SOD), catalase (CAT), glutation-peroxidasa (GPx), glutation-reductasa (MO), glucosa-6-fosfato-deshidrogenasa (G6PDH), as well as estersas serum paraoxonasa (PON1) using 3 substrates different (paraoxón, phenylacetate and diazoxón) and colinesterasas (BChE and AChE) in 135 applicators of pesticides to perform their activity on a regular basis in intensive farming under plastic on the coast of Almeria and Granada as well as 55 individuals from the same area but were not exposed and who served as controls. After adjusting enzyme levels by sex, age, BMI, exposure to pesticides, snuff and alcohol consumption, serum cholinesterase phenotype (compared to the usual unusual) and paraoxonasa (RR and QR isoforms versus QQ) found that exposure to pesticides independently predicts a lower activity SW, SOD and colinesterasas. These results confirm that chronic exposure to pesticides in an environment of intensive agriculture creates oxidative stress as evidenced by a decline in GA and SOD activities, which supports the involvement of the same mechanism of action of toxic pesticides. This means that both activities could constitute biomarkers effect in the context of chronic exposure to plaguicididas. Moreover, the different substrates used to determine the PON1, only diazoxón (activity diazoxonasa) has shown a significant association with exposure to pesticides, so that the exposed individuals have a lower enzyme activity which points to its potential usefulness as biomarcador exposure and / or effect.

Author: VICENTE SANCHEZ CESAREO.
Year: 2004.
University: SALAMANCA [More theses of this university] [www.usal.es].
Place of defense: FACULTAD DE FARMACIA.
Place of preparation: DEPARTAMENTO DE FISIOLOGIA Y FARMACOLOGIA.

Summary: The increase in the annual production of cadmium (Cd) has encouraged that the incidence for chronic intoxication to this element has increased. Oxidative stress is one of the mechanisms involved in the generation of toxic effect, manifesting itself by a kidney damage. The quercetin (Q) is a potent antioxidant, a chelator of metals and has been referenced, as well, anti-inflammatory properties. The objective of our study was to explore the possible protective effect of Q-induced nephrotoxicity in Cd. The experiments were conducted with Wistar rats, divided into four groups: a) Control Panel. 2) Group Cd: which is administered Cd (1.2 mg / kg / day, sc) for 9 weeks, 3) Group Q: When it was administered Q (50 mg / kg / day, ip) for 5 weeks 4) Group Cd + Q: Cd which was administered during 9 weeks and Q for 5 weeks, starting the administration to the fourth week starting with Cd. Urine samples were obtained in 24 hours, blood, kidney and liver before starting the treatment, all three, at six weeks and at the end of the study. To assess renal toxicity was analyzed renal function, enzyme markers of renal damage and alterations in renal tubular cells. Concentration of TBARS, total plasma antioxidant enzymes and antioxidants were measured to study oxidative stress. The implication of metalotioneínas (MTs) on the protective effect of Q and its anti-inflammatory activity was analyzed by measuring the expression of MTs, eNOS and COX-2 by Western blot and the expression of mRNA of MTs and eNOS by Northern blot. Chronic administration of Cd produces renal damage by an increase in oxidative stress and inflammation. Treatment with Q prevents this damage, probably for their antioxidant and anti-inflammatory properties and the increase in the expression of MTs.

Author: Martínez López Emma.
Year: 2005.
University: MURCIA [More theses of this university] [www.um.es].
Place of defense: Facultad de Veterinaria.
Place of preparation: Facultad de Veterinaria.

Author: LINARES VIDAL VICTORIA.
Year: 2005.
University: ROVIRA I VIRGILI [More theses of this university] [www.urv.cat].
Place of defense: FACULTAT DE MEDICINA I CIÈNCIES DE LA SALUT.
Place of preparation: FACULTAT DE MEDICINA I CIÈNCIES DE LA SALUT.

Author: QUESADA PAREDES MARIA ENCARNACION.
Year: 2005.
University: MIGUEL HERNÁNDEZ DE ELCHE [More theses of this university] [www.umh.es].
Place of defense: DEPARTAMENTO DE BIOLOGA APLICADA.
Place of preparation: MIGUEL HERNANDEZ.

Summary: "Induced delayed neuropathy organophosphorus compounds (OPIDN) is a neurodegenerative syndrome that starts with the inhibition and specific modification (" aging ") of the neuropathy target esterase (NTE). The brain of chicken is a very important source of NTE and why this fabric is most common model for the study of the enzyme. However, previous studies conducted in our laboratory have shown that bovine adrenal medulla has the highest levels of NTE described so far. The present work has been done a characterization of the NTE and other related esterases in homogenizado and soluble and particulate fractions of adrenal medulla several species of animals (cattle, pigs, goats, sheep and equine). The activity fenilvalerato esterase (PV esterase) and the total NTE was higher in particulate fraction (P) in soluble fraction (S) in all species. The species that showed increased activity in P NTE was bovines (4260Â ± 720 mU / g tissue) followed by swine, sheep, goats and equine. The percentage of NTE front of the PV esterase activity was higher in all bovine (70%) followed by swine (57%) Once elected bovine model as more appropriate, we proceeded to the characterization of the activities PV esterases cell cromafines cattle. The PV esterase activity and the total NTE found in this system was 22Â ± 3 and 12Â ± 2 mU/106 cells respectively, bringing the NTE accounted for 55% of total activity. The cells cromafines showed kinetics of inhibition by paraoxon and mipafox very similar to the one that showed the homogenizado of bovine adrenal medulla. It has been shown that the activity NTE inhibited by POs neuropathic as mipafox or HDCP recovers fully or partially to 120 hours of inhibition for 60 min. It has also carried out the construction of an adenovirus containing the gene for human activity NTE (Ad-NTEh) that has been achieved sobreexpresar controladamente activity NTE cell cromafines cattle growing. When the cells were infected with 16 Â µ l Ad-NTEh activity NTE increased more than four times over the activity NTE control. This system is intended to analyze the role of NTE in the physiology of the cell cromafin. The results presented in this study strongly support the use of primary culture cells cromafines as an in vitro model for alternative and appropriate studies neurotoxicity induced by organophosphates (OPs).

Author: MIÑAMBRES HERRÁIZ REBECA.
Year: 2005.
University: VALENCIA [More theses of this university] [www.uv.es].
Place of defense: FACULTAD DE MEDICINA DE LA UNIVERSITAT DE VALÈNCIA.
Place of preparation: FUNDACIÓN VALENCIANA DE INVESTIGACIONES MÉDICAS-CENTRO DE INV. PRINCIPE FELIPE.

Summary: The cells astrogiales are a target of the effects of ethanol during development of the brain, and that alters both on the survival of astrocytes. This work demonstrates that ethanol alters the path of Rho signaling proteins, affecting the organization of the actin cytoskeleton and focal adhesions. In particular route signaling RhoA / ROCK-I / MLCpp is involved in apoptosis induced by ethanol in astrocytes.

Author: BABOT RIERA ZOILA.
Year: 2005.
University: BARCELONA [More theses of this university] [www.ub.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: FACULTAD DE MEDICINA.

Summary: The glutamate and GABA are respectively the main neurotransmitter exciter and inhbidiro central nervous system. A balance between these two systems wrong neurotransmitter results in pathological states. An excess of glutamate, produces neurotoxicitat by a mechanism dependent on the entry of Ca2 + through the NMDA receptor glutamate. This process is known as exitotoxicidad. The role of the neurotransmitter GABA in the process of exitotoxicidad is unclear. While some works describe that increased neurotransmissión GABAérgica is protective of excitotoxicidad, others describe the case. The acute exposure to organochlorine pesticide dieldrin produced in humans and experimental animals, syndrome hiperexcitabilidad, causing convulsions that can result in death. This effect is explained by the action antagonist dieldrin in the receiver GABA-A. This pesticide is no longer used in developed countries. However, due to its high persistence and bioaccumulation, for use in underdeveloped countries and their ability to travel long distances, currently the general population around the world continues exposed to this pesticide. So, today, dieldrin is deemed a "persistent organic pollutants (POPs). While aware of the acute effects of exposure to dieldrin, are unclear adverse effects on the central nervous system that could produce long-term exposure to low concentrations of dieldrin. In this thesis develops a model of excitotoxicidad in primary cultures of granular cells of the cerebellum, based on the release of glutamate engógeno. This model considers the involvement receptor GABA-Ay other channels chloride in the death excitotóxica. It describes the entry of chloride across the receiver GABA-Ay channel chloride dependent acid inflúmico increases exitotoxicidad. In addition, we study the effects of concentrations subcitotóxicas of dieldrin on the systems GABAérgico and glutamatérgico in cell cultures of cerebellum granule exposed for prolonged periods. It describes the partial blockade receptor GABAA induced dieldrin, produces a compensatory response in the NMDA glutamate receptors (decrease), so that when the crops are exposed to the stimulus excitotóxico previously described, there is excitotoxicidad.

Author: GALLARDO ALBA MARIA EUGENIA.
Year: 2005.
University: SANTIAGO DE COMPOSTELA [More theses of this university] [www.usc.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: FACULTAD DE MEDICINA.

Summary: The organophosphates have been, since its discovery in 1854, the group most commonly used pesticides, and have placed an alternative to other biocides. His low persistence in the environment has been the key element of its enormous potential for use. While poisoning these compounds do not constitute a health problem of the first magnitude when compared to those occurring with other chemicals, there are important reasons that justify the need for a clear and precise methodology for detection and identification. This report proposes a method of analysis based on Microextracción in Solid Phase mode of direct immersion (SPME-DI) coupled to the Gas Chromatography / Mass Spectrometry for determining dimethoate, diazinon, parathion, quinalfos, azinphos methyl, chlorpyrifos, clorfenvinfos and paraoxón in samples of blood and urine. As internal standard was used for ethion. To perform this work, we assessed two kinds of fiber: polydimethylsiloxane and carbowax MT / divinilbenzeno of 100 and 65 um thick. The best results were obtained with the latter. They optimized the main parameters that influence the SPME: sample volume, precipitation of proteins, extraction time and desorption, temperature, agitation of the sample, pH modification and addition of salts. After optimization, the final terms of extraction were in a glass tube was pipetearon 100 uL sample (blood or urine) to which were added 10 uL internal standard concentration 100 ug / mL and Milli - Q water until complete a final volume of 1mL. After shaking vigorously displays, fiber contacted it. After 60 minutes of extraction 60Â ° C (blood) or 90Â ° C (urine), the fiber was collected for subsequent desorption in the nozzle of gas chromatograph to 240Â ° C for 1 minute. The methodology described was validated in accordance with validation parameters covered by international organizations. These parameters were: selectivity, calibration curve, precision and accuracy, limits of detection and quantification, recovery, dilution of samples and stability. The method is selective and showed that there was no interference in the retention times and Ion selected for each of the analytes study. Linearity was obtained within the ranges studied: 0,05-50,0 and 0,01-50,0 ug / mL for the quinalfos and parathion in blood and urine, respectively, and 0,5-50,0 and 0.1 - 40.0 ug / mL for dimethoate in blood and urine, respectively. The values obtained for the precision and accuracy, expressed as coefficients of variation and airways were less than 15% for all the concentrations studied in both arrays, according to the criteria of validation adopted. The limits of detection in urine obtained ranged between 2n/mL for quinalfos and dizainón and 50 ng / mL for dimethoate. In blood, these values ranged from 4ng/mL for clorfenvinfos and diazinon and 250 ng / mL for azinphos methyl. The limits of quantification obtained in urine ranged from 10ng/mL for quinalfos and parathion and 100 ng / mL for dimethoate. In blood, these values ranged from 50 ng / mL for quinalfos and parathion and 500 ng / mL for dimethoate. The recovery for dimethoate was 1.25% in urine and 0.50 in blood for parathion, 35.06% and 6.58% in the urine in the blood, and for quinalfos 26.26% in the urine and 14, 19% in blood. Finally, the method was applied to 99 real samples from autopsiasmedico-legales and hospitals. This methodology is an alternative to conventional extraction methods, such as solid or liquid-liquid extraction, for the determination of organophosphorus pesticides in biological means in the field of Clinical and Forensic Toxicology.

Author: ALDONZA TORRES MARTA.
Year: 2005.
University: SANTIAGO DE COMPOSTELA [More theses of this university] [www.usc.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: FACULTAD DE MEDICINA.

Summary: In recent years there was a clear expansion of cocaine, mainly among the younger population. Although the number of deaths due solely to abuse of cocaine is small, its consumption produces many acute and chronic poisoning, with a consequent rise in emergency clinics and demand for therapeutic support, a serious social welfare. The diagnosis of cocaine overdose on it is mainly based on laboratory tests, which have to be sensitive and specific in ensuring a correct identification of drugs in different biological fluids. In this report we design a method of using a gas chromatography ionisation detector floorboard and one High Resolution Liquid chromatography with UV detector for the simultaneous determination of cocaine and its major metabolites (benzoilecgonina and ecgonian methyl éser) in two non-biological fluids customary in toxicological analysis such as vitreous humor and bile. These two types of samples can be very useful in those cases are not available blood or urine or when the body is in poor condition (serious burn, embalmed, etc.). After several trials using an extraction procedure with which we manage solid performance superior to 70% for all chemicals tested. We produced the straight calibration in the range 0,1-4ug / mL in Gas Chromatography and 0125-5ug/mL in Liquid Chromatography demonstrating good linearity in two types of samples. The detection limits were always suitable for the analysis of forensic samples and the study of the accuracy of the accuracy was also satisfactory. These methods were applied to samples from deceased patients by cocaine intoxication, associated in most cases to the coexistence of other drugs, which could have influenced the great variability of the results. In samples of vitreous humor is usually higher concentrations of metabolites of cocaine, although samples bile generally having higher levels of metabolites. We compared a good correlation between the two techniques. However, there was a significant correlation between the concentrations of cocaine and its metabolites in samples of vitreous humor and bile from the same subject.