Veronica Rodriguez - Academia.edu (original) (raw)
Papers by Veronica Rodriguez
NeuroImage, 2004
A method for the exploratory analysis of electroencephalographic (EEG) data for neurophysiologica... more A method for the exploratory analysis of electroencephalographic (EEG) data for neurophysiological experiments is presented. It is based on a time-frequency decomposition of the EEG time series, which is measured by several electrodes in the scalp surface, and includes the computation of a statistic that measures the deviations of the log-power with respect to the pre-stimulus average; the computation of a significance index for these deviations; a new type of display (the time-frequency-topography plot) for the visualization of these indices, and the segmentation of the time-frequency plane into regions with uniform activation patterns. As a particular example, an experiment to study EEG changes during figure and word categorization is analyzed in detail.
Revista Española de Enfermedades Digestivas, 2008
ABSTRACT
Neurotoxicology and Teratology, 2011
The herbicide atrazine (ATR) is widely used around the world, and is a potential toxicant of the ... more The herbicide atrazine (ATR) is widely used around the world, and is a potential toxicant of the dopaminergic systems. Nigrostriatal and mesolimbic systems are the two major dopaminergic pathways of the central nervous system; they play key roles mediating a wide array of critical motor and cognitive functions. We evaluated the effects of exposing male rats for one year to 10 mg ATR/kg B.W. on these systems using motor and cognitive tasks and measuring monoamine content in the striatum, nucleus accumbens, prefrontal cortex, and hypothalamus. ATR administration resulted in impaired motor coordination and greater spontaneous locomotor activity only after 10 to 12 months of exposure. Chronic exposure to 10 mg ATR decreased striatal dopamine, but had no effect on accumbal, hypothalamic or cortical monoamine content. Chronic ATR exposure caused discrete changes in learning tasks that involve either the striatum or the nucleus accumbens. These results indicate that chronic exposure to ATR preferentially targets the nigrostriatal dopaminergic pathway, in comparison to the other dopaminergic pathways evaluated in this study, inducing behavioral and neurochemical alterations. In order to unveil the full extent of atrazine's effects on the nervous system, other neurochemical systems should be considered in future studies.
NeuroToxicology, 2015
Glyphosate (Glyph) is the active ingredient of several herbicide formulations. Reports of Glyph e... more Glyphosate (Glyph) is the active ingredient of several herbicide formulations. Reports of Glyph exposure in humans and animal models suggest that it may be neurotoxic. To evaluate the effects of Glyph on the nervous system, male Sprague-Dawley rats were given six intraperitoneal injections of 50, 100, or 150mg Glyph/kg BW over 2 weeks (three injections/week). We assessed dopaminergic markers and their association with locomotor activity. Repeated exposure to Glyph caused hypoactivity immediately after each injection, and it was also apparent 2 days after the last injection in rats exposed to the highest dose. Glyph did not decrease monoamines, tyrosine hydroxylase (TH), or mesencephalic TH+ cells when measured 2 or 16 days after the last Glyph injection. In contrast, Glyph decreased specific binding to D1 dopamine (DA) receptors in the nucleus accumbens (NAcc) when measured 2 days after the last Glyph injection. Microdialysis experiments showed that a systemic injection of 150mg Glyph/kg BW decreased basal extracellular DA levels and high-potassium-induced DA release in striatum. Glyph did not affect the extracellular concentrations of 3,4-dihydroxyphenylacetic acid or homovanillic acid. These results indicate that repeated Glyph exposure results in hypoactivity accompanied by decreases in specific binding to D1-DA receptors in the NAcc, and that acute exposure to Glyph has evident effects on striatal DA levels. Additional experiments are necessary in order to unveil the specific targets of Glyph on dopaminergic system, and whether Glyph could be affecting other neurotransmitter systems involved in motor control.
Toxicology and Applied Pharmacology, 2009
Arsenic (As) is a toxic metalloid widely present in the environment. Human exposure to As has bee... more Arsenic (As) is a toxic metalloid widely present in the environment. Human exposure to As has been associated with the development of skin and internal organ cancers and cardiovascular disorders, among other diseases. A few studies report decreases in intelligence quotient (IQ), and sensory and motor alterations after chronic As exposure in humans. On the other hand, studies of rodents exposed to high doses of As have found alterations in locomotor activity, brain neurochemistry, behavioral tasks, and oxidative stress. In the present study both male and female C57Bl/6J mice were exposed to environmentally relevant doses of As such as 0.05, 0.5, 5.0, or 50 mg As/L of drinking water for 4 months, and locomotor activity was assessed every month. Male mice presented hyperactivity in the group exposed to 0.5 mg As/L and hypoactivity in the group exposed to 50 mg As/L after 4 months of As exposure, whereas female mice exposed to 0.05, 0.5, and 5.0 mg As/L exhibited hyperactivity in every monthly test during As exposure. Furthermore, striatal and hypothalamic dopamine content was decreased only in female mice. Also decreases in tyrosine hydroxylase (TH) and cytosolic thioredoxin (Trx-1) mRNA expression in striatum and nucleus accumbens were observed in male and female mice, respectively. These results indicate that chronic As exposure leads to gender-dependent alterations in dopaminergic markers and spontaneous locomotor activity, and down-regulation of the antioxidant capacity of the brain.
![Research paper thumbnail of Corrigendum to “Chronic low-level arsenic exposure causes gender-specific alterations in locomotor activity, dopaminergic systems, and thioredoxin expression in mice” [Toxicology and Applied Pharmacology (2009) 169–177]](https://attachments.academia-assets.com/44276814/thumbnails/1.jpg)
](Toxicology and Applied Pharmacology, 2010
The authors regret that in the results section under spontaneous locomotor activity, the degrees ... more The authors regret that in the results section under spontaneous locomotor activity, the degrees of freedom for the effect of sample-time were incorrect.
Phytochemistry, 1997
Eucnide bartonioides yielded morroniside as the main iridoid constituent. In addition, six minor ... more Eucnide bartonioides yielded morroniside as the main iridoid constituent. In addition, six minor iridoid glucosides were isolated namely the known glucosides: kingiside, sweroside, secologanol, 8-epi-loganin and loganin as well as a novel iridoid glucoside, which by spectroscopic methods was assigned to be 5hydroxyloganin.
Phytochemistry, 1991
ABSTRACT
Neurotoxicology and Teratology, 2010
Several studies have associated chronic arsenicism with decreases in IQ and sensory and motor alt... more Several studies have associated chronic arsenicism with decreases in IQ and sensory and motor alterations in humans. Likewise, studies of rodents exposed to inorganic arsenic ( i As) have found changes in locomotor activity, brain neurochemistry, behavioral tasks, oxidative stress, and in sensory and motor nerves. In the current study, male Sprague-Dawley rats were exposed to environmentally relevant doses of i As (0.05, 0.5 mg i As/L) and to a high dose (50 mg i As/L) in drinking water for one year. Hypoactivity and increases in the striatal dopamine content were found in the group treated with 50 mg i As/L. Exposure to 0.5 and 50 mg i As/L increased the total brain content of As. Furthermore, i As exposure produced a dose-dependent upregulation of mRNA for Mn-SOD and Trx-1 and a down-regulation of DAR-D 2 mRNA levels in the nucleus accumbens. DAR-D 1 and Nrf2 mRNA expression were down-regulated in nucleus accumbens in the group exposed to 50 mg i As/L. Trx-1 mRNA levels were up-regulated in the cortex in an i As dose-dependent manner, while DAR-D 1 mRNA expression was increased in striatum in the 0.5 mg i As/L group. These results show that chronic exposure to low levels of arsenic causes subtle but region-specific changes in the nervous system, especially in antioxidant systems and dopaminergic elements. These changes became behaviorally evident only in the group exposed to 50 mg i As/L. i As in a brain region-specific manner following the order cortexN striatum N hippocampus N hypothalamus N cerebellum, in comparison to a non-exposed control group .
NeuroImage, 2004
A method for the exploratory analysis of electroencephalographic (EEG) data for neurophysiologica... more A method for the exploratory analysis of electroencephalographic (EEG) data for neurophysiological experiments is presented. It is based on a time -frequency decomposition of the EEG time series, which is measured by several electrodes in the scalp surface, and includes the computation of a statistic that measures the deviations of the log-power with respect to the pre-stimulus average; the computation of a significance index for these deviations; a new type of display (the time -frequency -topography plot) for the visualization of these indices, and the segmentation of the time -frequency plane into regions with uniform activation patterns. As a particular example, an experiment to study EEG changes during figure and word categorization is analyzed in detail. D
Journal of Natural Products, 1992
A new acetylated ent-atisene glycoside, stevisalioside A [1], has been isolated as a bitter-tasti... more A new acetylated ent-atisene glycoside, stevisalioside A [1], has been isolated as a bitter-tasting principle from Stevia salicifolia roots. The structure was established by the interpretation of spectral data, with the nmr assignments of this compound being based on 1H-1H COSY, 1H-13C HETCOR, and selective INEPT experiments. A rearrangement product 4 of the aglycone moiety obtained by alkaline hydrolysis supported the structure of 1. This is the first report of the occurrence of an atisane-type diterpene from the genus Stevia.
Indian Dermatology Online Journal, 2014
Basal cell carcinomas (BCC) on the genital area account for less than 1% of all BCCs. Surgical ma... more Basal cell carcinomas (BCC) on the genital area account for less than 1% of all BCCs. Surgical management is indicated. Recurrence rate of vulvar BCC has been reported to be 10-20%. Mohs micrographic surgery (MMS) is a superior surgical option. Other treatments include radiation and topical immuntherapy. Cryosurgery for vulvar BCC has not been reported. We present the case of a 88-year-old Hispanic woman with a vulvar ulcer that was confirmed as BCC by histopathology and treated with liquid nitrogen cryosurgery. Control biopsy was performed on day 90 was negative for BCC. No clinical evidence of recurrence was detected after one year. Although, the vulva is considered to be a high-risk site with respect to BCC and MMS is the gold standard for treatment, the delicate nature of the area may preclude complete removal by a surgical technique without compromising vital anatomical function. Liquid nitrogen cryosurgery uses the effects of extreme cold to effect deep destruction of the tumor and surrounding tissues. This is the first report of a vulvar BCC successfully treated with liquid nitrogen cryosurgery. We suggest this technique could be of benefit as an alternative treatment in cases where excisional procedures cannot be performed.
Enzyme and Microbial Technology, 1998
We have studied the production of phenylpyruvic acid by mild stereospecific oxidation of d-phenyl... more We have studied the production of phenylpyruvic acid by mild stereospecific oxidation of d-phenylalanine (from d/l racemic mixtures) catalyzed by d-amino acid oxidase (DAAO) from Trigonopsis variabilis. The performance of this reaction requires the continuous bubbling of oxygen that inactivated soluble DAAO. The immobilization of the enzyme inside porous supports avoids the interaction of the enzyme with the hydrophobic oxygen/water
Environmental Health Perspectives, 2012
The widespread use of atrazine (ATR) and its persistence in the environment have resulted in docu... more The widespread use of atrazine (ATR) and its persistence in the environment have resulted in documented human exposure. Alterations in hypothalamic catecholamines have been suggested as the mechanistic basis of the toxicity of ATR to hormonal systems in females and the reproductive tract in males. Because multiple catecholamine systems are present in the brain, however, ATR could have far broader effects than are currently understood. Catecholaminergic systems such as the two major long-length dopaminergic tracts of the central nervous system play key roles in mediating a wide array of critical behavioral functions. In this study we examined the hypothesis that ATR would adversely affect these brain dopaminergic systems. Male rats chronically exposed to 5 or 10 mg/kg ATR in the diet for 6 months exhibited persistent hyperactivity and altered behavioral responsivity to amphetamine. Moreover, when measured 2 weeks after the end of exposure, the levels of various monoamines and the numbers of tyrosine hydroxylase-positive (TH + ) and -negative (TH -) cells measured using unbiased stereology were reduced in both dopaminergic tracts. Acute exposures to 100 or 200 mg/kg ATR given intraperitoneally to evaluate potential mechanisms reduced both basal and potassium-evoked striatal dopamine release. Collectively, these studies demonstrate that ATR can produce neurotoxicity in dopaminergic systems that are critical to the mediation of movement as well as cognition and executive function. Therefore, ATR may be an environmental risk factor contributing to dopaminergic system disorders, underscoring the need for further investigation of its mechanism(s) of action and corresponding assessment of its associated human health risks. Key words: atrazine, dopamine, hypothalamus, locomotor activity, microdialysis, prefrontal cortex, striatum, substantia nigra, unbiased stereology. Environ Health Perspect 113:708-715 (2005). doi:10.1289/ehp.7783 available via http://dx.doi.org/ [Online 24 February 2005]
Toxicological …, 2005
Inorganic arsenic exposure via drinking water has been associated with cancer and serious injury ... more Inorganic arsenic exposure via drinking water has been associated with cancer and serious injury in various internal organs, as well as with peripheral neuropathy and diverse effects in the nervous system. Alterations in memory and attention processes have been reported in ...
Acta Anaesthesiologica Scandinavica, 2001
Background: Prolonged postoperative blockade can follow neuraxial blocks for short surgical proce... more Background: Prolonged postoperative blockade can follow neuraxial blocks for short surgical procedures. We investigated whether washout with a high volume of saline through an epidural catheter could provide a faster recovery after epidural anaesthesia. Methods: Thirty patients were randomly assigned to a control group (no washout), to group 2¿ (epidural washout with twice the volume of 2% mepivacaine) and group 4¿ (epidural washout with four times that volume). Results: Recovery times from sensory blockade at L2 were 151∫24, 122∫29 and 116∫24 min for control, 2¿ and 4¿ groups respectively. Significant differences were found in both saline groups when compared with control group, but not between group 2¿ and group 4¿. No differences were found concerning
NeuroImage, 2004
A method for the exploratory analysis of electroencephalographic (EEG) data for neurophysiologica... more A method for the exploratory analysis of electroencephalographic (EEG) data for neurophysiological experiments is presented. It is based on a time-frequency decomposition of the EEG time series, which is measured by several electrodes in the scalp surface, and includes the computation of a statistic that measures the deviations of the log-power with respect to the pre-stimulus average; the computation of a significance index for these deviations; a new type of display (the time-frequency-topography plot) for the visualization of these indices, and the segmentation of the time-frequency plane into regions with uniform activation patterns. As a particular example, an experiment to study EEG changes during figure and word categorization is analyzed in detail.
Revista Española de Enfermedades Digestivas, 2008
ABSTRACT
Neurotoxicology and Teratology, 2011
The herbicide atrazine (ATR) is widely used around the world, and is a potential toxicant of the ... more The herbicide atrazine (ATR) is widely used around the world, and is a potential toxicant of the dopaminergic systems. Nigrostriatal and mesolimbic systems are the two major dopaminergic pathways of the central nervous system; they play key roles mediating a wide array of critical motor and cognitive functions. We evaluated the effects of exposing male rats for one year to 10 mg ATR/kg B.W. on these systems using motor and cognitive tasks and measuring monoamine content in the striatum, nucleus accumbens, prefrontal cortex, and hypothalamus. ATR administration resulted in impaired motor coordination and greater spontaneous locomotor activity only after 10 to 12 months of exposure. Chronic exposure to 10 mg ATR decreased striatal dopamine, but had no effect on accumbal, hypothalamic or cortical monoamine content. Chronic ATR exposure caused discrete changes in learning tasks that involve either the striatum or the nucleus accumbens. These results indicate that chronic exposure to ATR preferentially targets the nigrostriatal dopaminergic pathway, in comparison to the other dopaminergic pathways evaluated in this study, inducing behavioral and neurochemical alterations. In order to unveil the full extent of atrazine's effects on the nervous system, other neurochemical systems should be considered in future studies.
NeuroToxicology, 2015
Glyphosate (Glyph) is the active ingredient of several herbicide formulations. Reports of Glyph e... more Glyphosate (Glyph) is the active ingredient of several herbicide formulations. Reports of Glyph exposure in humans and animal models suggest that it may be neurotoxic. To evaluate the effects of Glyph on the nervous system, male Sprague-Dawley rats were given six intraperitoneal injections of 50, 100, or 150mg Glyph/kg BW over 2 weeks (three injections/week). We assessed dopaminergic markers and their association with locomotor activity. Repeated exposure to Glyph caused hypoactivity immediately after each injection, and it was also apparent 2 days after the last injection in rats exposed to the highest dose. Glyph did not decrease monoamines, tyrosine hydroxylase (TH), or mesencephalic TH+ cells when measured 2 or 16 days after the last Glyph injection. In contrast, Glyph decreased specific binding to D1 dopamine (DA) receptors in the nucleus accumbens (NAcc) when measured 2 days after the last Glyph injection. Microdialysis experiments showed that a systemic injection of 150mg Glyph/kg BW decreased basal extracellular DA levels and high-potassium-induced DA release in striatum. Glyph did not affect the extracellular concentrations of 3,4-dihydroxyphenylacetic acid or homovanillic acid. These results indicate that repeated Glyph exposure results in hypoactivity accompanied by decreases in specific binding to D1-DA receptors in the NAcc, and that acute exposure to Glyph has evident effects on striatal DA levels. Additional experiments are necessary in order to unveil the specific targets of Glyph on dopaminergic system, and whether Glyph could be affecting other neurotransmitter systems involved in motor control.
Toxicology and Applied Pharmacology, 2009
Arsenic (As) is a toxic metalloid widely present in the environment. Human exposure to As has bee... more Arsenic (As) is a toxic metalloid widely present in the environment. Human exposure to As has been associated with the development of skin and internal organ cancers and cardiovascular disorders, among other diseases. A few studies report decreases in intelligence quotient (IQ), and sensory and motor alterations after chronic As exposure in humans. On the other hand, studies of rodents exposed to high doses of As have found alterations in locomotor activity, brain neurochemistry, behavioral tasks, and oxidative stress. In the present study both male and female C57Bl/6J mice were exposed to environmentally relevant doses of As such as 0.05, 0.5, 5.0, or 50 mg As/L of drinking water for 4 months, and locomotor activity was assessed every month. Male mice presented hyperactivity in the group exposed to 0.5 mg As/L and hypoactivity in the group exposed to 50 mg As/L after 4 months of As exposure, whereas female mice exposed to 0.05, 0.5, and 5.0 mg As/L exhibited hyperactivity in every monthly test during As exposure. Furthermore, striatal and hypothalamic dopamine content was decreased only in female mice. Also decreases in tyrosine hydroxylase (TH) and cytosolic thioredoxin (Trx-1) mRNA expression in striatum and nucleus accumbens were observed in male and female mice, respectively. These results indicate that chronic As exposure leads to gender-dependent alterations in dopaminergic markers and spontaneous locomotor activity, and down-regulation of the antioxidant capacity of the brain.
Toxicology and Applied Pharmacology, 2010
The authors regret that in the results section under spontaneous locomotor activity, the degrees ... more The authors regret that in the results section under spontaneous locomotor activity, the degrees of freedom for the effect of sample-time were incorrect.
Phytochemistry, 1997
Eucnide bartonioides yielded morroniside as the main iridoid constituent. In addition, six minor ... more Eucnide bartonioides yielded morroniside as the main iridoid constituent. In addition, six minor iridoid glucosides were isolated namely the known glucosides: kingiside, sweroside, secologanol, 8-epi-loganin and loganin as well as a novel iridoid glucoside, which by spectroscopic methods was assigned to be 5hydroxyloganin.
Phytochemistry, 1991
ABSTRACT
Neurotoxicology and Teratology, 2010
Several studies have associated chronic arsenicism with decreases in IQ and sensory and motor alt... more Several studies have associated chronic arsenicism with decreases in IQ and sensory and motor alterations in humans. Likewise, studies of rodents exposed to inorganic arsenic ( i As) have found changes in locomotor activity, brain neurochemistry, behavioral tasks, oxidative stress, and in sensory and motor nerves. In the current study, male Sprague-Dawley rats were exposed to environmentally relevant doses of i As (0.05, 0.5 mg i As/L) and to a high dose (50 mg i As/L) in drinking water for one year. Hypoactivity and increases in the striatal dopamine content were found in the group treated with 50 mg i As/L. Exposure to 0.5 and 50 mg i As/L increased the total brain content of As. Furthermore, i As exposure produced a dose-dependent upregulation of mRNA for Mn-SOD and Trx-1 and a down-regulation of DAR-D 2 mRNA levels in the nucleus accumbens. DAR-D 1 and Nrf2 mRNA expression were down-regulated in nucleus accumbens in the group exposed to 50 mg i As/L. Trx-1 mRNA levels were up-regulated in the cortex in an i As dose-dependent manner, while DAR-D 1 mRNA expression was increased in striatum in the 0.5 mg i As/L group. These results show that chronic exposure to low levels of arsenic causes subtle but region-specific changes in the nervous system, especially in antioxidant systems and dopaminergic elements. These changes became behaviorally evident only in the group exposed to 50 mg i As/L. i As in a brain region-specific manner following the order cortexN striatum N hippocampus N hypothalamus N cerebellum, in comparison to a non-exposed control group .
NeuroImage, 2004
A method for the exploratory analysis of electroencephalographic (EEG) data for neurophysiologica... more A method for the exploratory analysis of electroencephalographic (EEG) data for neurophysiological experiments is presented. It is based on a time -frequency decomposition of the EEG time series, which is measured by several electrodes in the scalp surface, and includes the computation of a statistic that measures the deviations of the log-power with respect to the pre-stimulus average; the computation of a significance index for these deviations; a new type of display (the time -frequency -topography plot) for the visualization of these indices, and the segmentation of the time -frequency plane into regions with uniform activation patterns. As a particular example, an experiment to study EEG changes during figure and word categorization is analyzed in detail. D
Journal of Natural Products, 1992
A new acetylated ent-atisene glycoside, stevisalioside A [1], has been isolated as a bitter-tasti... more A new acetylated ent-atisene glycoside, stevisalioside A [1], has been isolated as a bitter-tasting principle from Stevia salicifolia roots. The structure was established by the interpretation of spectral data, with the nmr assignments of this compound being based on 1H-1H COSY, 1H-13C HETCOR, and selective INEPT experiments. A rearrangement product 4 of the aglycone moiety obtained by alkaline hydrolysis supported the structure of 1. This is the first report of the occurrence of an atisane-type diterpene from the genus Stevia.
Indian Dermatology Online Journal, 2014
Basal cell carcinomas (BCC) on the genital area account for less than 1% of all BCCs. Surgical ma... more Basal cell carcinomas (BCC) on the genital area account for less than 1% of all BCCs. Surgical management is indicated. Recurrence rate of vulvar BCC has been reported to be 10-20%. Mohs micrographic surgery (MMS) is a superior surgical option. Other treatments include radiation and topical immuntherapy. Cryosurgery for vulvar BCC has not been reported. We present the case of a 88-year-old Hispanic woman with a vulvar ulcer that was confirmed as BCC by histopathology and treated with liquid nitrogen cryosurgery. Control biopsy was performed on day 90 was negative for BCC. No clinical evidence of recurrence was detected after one year. Although, the vulva is considered to be a high-risk site with respect to BCC and MMS is the gold standard for treatment, the delicate nature of the area may preclude complete removal by a surgical technique without compromising vital anatomical function. Liquid nitrogen cryosurgery uses the effects of extreme cold to effect deep destruction of the tumor and surrounding tissues. This is the first report of a vulvar BCC successfully treated with liquid nitrogen cryosurgery. We suggest this technique could be of benefit as an alternative treatment in cases where excisional procedures cannot be performed.
Enzyme and Microbial Technology, 1998
We have studied the production of phenylpyruvic acid by mild stereospecific oxidation of d-phenyl... more We have studied the production of phenylpyruvic acid by mild stereospecific oxidation of d-phenylalanine (from d/l racemic mixtures) catalyzed by d-amino acid oxidase (DAAO) from Trigonopsis variabilis. The performance of this reaction requires the continuous bubbling of oxygen that inactivated soluble DAAO. The immobilization of the enzyme inside porous supports avoids the interaction of the enzyme with the hydrophobic oxygen/water
Environmental Health Perspectives, 2012
The widespread use of atrazine (ATR) and its persistence in the environment have resulted in docu... more The widespread use of atrazine (ATR) and its persistence in the environment have resulted in documented human exposure. Alterations in hypothalamic catecholamines have been suggested as the mechanistic basis of the toxicity of ATR to hormonal systems in females and the reproductive tract in males. Because multiple catecholamine systems are present in the brain, however, ATR could have far broader effects than are currently understood. Catecholaminergic systems such as the two major long-length dopaminergic tracts of the central nervous system play key roles in mediating a wide array of critical behavioral functions. In this study we examined the hypothesis that ATR would adversely affect these brain dopaminergic systems. Male rats chronically exposed to 5 or 10 mg/kg ATR in the diet for 6 months exhibited persistent hyperactivity and altered behavioral responsivity to amphetamine. Moreover, when measured 2 weeks after the end of exposure, the levels of various monoamines and the numbers of tyrosine hydroxylase-positive (TH + ) and -negative (TH -) cells measured using unbiased stereology were reduced in both dopaminergic tracts. Acute exposures to 100 or 200 mg/kg ATR given intraperitoneally to evaluate potential mechanisms reduced both basal and potassium-evoked striatal dopamine release. Collectively, these studies demonstrate that ATR can produce neurotoxicity in dopaminergic systems that are critical to the mediation of movement as well as cognition and executive function. Therefore, ATR may be an environmental risk factor contributing to dopaminergic system disorders, underscoring the need for further investigation of its mechanism(s) of action and corresponding assessment of its associated human health risks. Key words: atrazine, dopamine, hypothalamus, locomotor activity, microdialysis, prefrontal cortex, striatum, substantia nigra, unbiased stereology. Environ Health Perspect 113:708-715 (2005). doi:10.1289/ehp.7783 available via http://dx.doi.org/ [Online 24 February 2005]
Toxicological …, 2005
Inorganic arsenic exposure via drinking water has been associated with cancer and serious injury ... more Inorganic arsenic exposure via drinking water has been associated with cancer and serious injury in various internal organs, as well as with peripheral neuropathy and diverse effects in the nervous system. Alterations in memory and attention processes have been reported in ...
Acta Anaesthesiologica Scandinavica, 2001
Background: Prolonged postoperative blockade can follow neuraxial blocks for short surgical proce... more Background: Prolonged postoperative blockade can follow neuraxial blocks for short surgical procedures. We investigated whether washout with a high volume of saline through an epidural catheter could provide a faster recovery after epidural anaesthesia. Methods: Thirty patients were randomly assigned to a control group (no washout), to group 2¿ (epidural washout with twice the volume of 2% mepivacaine) and group 4¿ (epidural washout with four times that volume). Results: Recovery times from sensory blockade at L2 were 151∫24, 122∫29 and 116∫24 min for control, 2¿ and 4¿ groups respectively. Significant differences were found in both saline groups when compared with control group, but not between group 2¿ and group 4¿. No differences were found concerning