In this study, we investigated whether BDNF similarly promotes AMPAR trafficking in the adult rat NAc. After unilateral intracranial injection of BDNF into NAc core or shell, rats were killed at post-injection times ranging from 30 min to 3 days. NAc core or shell tissue from both injected and non-injected hemispheres was analysed by Western blotting. A protein cross-linking assay was used to measure AMPAR surface expression. Selleck R428 Assessment of tropomyosin receptor kinase

B signaling demonstrated that injected BDNF was biologically active. BDNF injection into NAc core, but not NAc shell, led to a protein synthesis- and extracellular signal-regulated kinase-dependent increase in cell surface GluA1 and a trend towards increased total GluA1. This was detected 30 min post-injection but not at longer time-points. GluA2 and GluA3 were unaffected, suggesting an effect of BDNF on homomeric GluA1

Ca2+-permeable AMPARs. These results demonstrate that exogenous BDNF rapidly check details increases AMPAR surface expression in the rat NAc core, raising the possibility of a relationship between increases in endogenous BDNF levels and alterations in AMPAR transmission observed in the NAc of cocaine-experienced rats. “
“The link between basic physiology and its modulation by cognitive states, such as attention, is poorly understood. A significant association becomes apparent when patients Paclitaxel with movement disorders describe experiences with changing their attention focus and the fundamental effect that this has on their motor symptoms. Moreover, frequently used mental strategies for treating such patients, e.g. with task-specific dystonia, widely lack laboratory-based knowledge about physiological mechanisms. In this largely unexplored field, we looked at how the locus of attention, when it changed between internal (locus hand) and external (visual target), influenced excitability in the primary motor cortex (M1) in healthy humans. Intriguingly, both

internal and external attention had the capacity to change M1 excitability. Both led to a reduced stimulation-induced GABA-related inhibition and a change in motor evoked potential size, i.e. an overall increased M1 excitability. These previously unreported findings indicated: (i) that cognitive state differentially interacted with M1 physiology, (ii) that our view of distraction (attention locus shifted towards external or distant location), which is used as a prevention or management strategy for use-dependent motor disorders, is too simple and currently unsupported for clinical application, and (iii) the physiological state reached through attention modulation represents an alternative explanation for frequently reported electrophysiology findings in neuropsychiatric disorders, such as an aberrant inhibition.

The database from which the information comes is encyclopedic in scope and detail, and is continually updated,

although the texts are renewed annually. Electronic reference links and the vaccine schedule listing for each country are just two of the highlights of the book. For the practitioner, it is certainly difficult to justify purchasing an entire series of books. However, as a reference, they can be quite valuable. For example, >12% of the US population of 300 million are foreign born. Scores of physicians see such patients and would benefit from having access to information about endemic diseases in their Bortezomib cell line patients’ home countries, even if some of these patients are to be referred to specialists. Similarly, those practicing immigrant health, those working in public health, international health, teachers, students, and those planning to live or work in countries other than their own would benefit from accessing some of these texts. However, there are limitations to a database that is encyclopedic. All diseases that have been reported in a country are listed as endemic or potentially endemic. Therefore, the reader does not get a sense of the relative importance of certain diseases within countries nor certainly within regions of a country. Statements regarding the endemicity of diseases can be puzzling as it may be of little

value to read that Q fever, cysticercosis, and leprosy are endemic or potentially so in all countries. Countries’ surveillance capacities and disease verification vary tremendously GNA12 and thus the full picture of the disease burden may not be correctly represented. learn more Although comprehensive, the clinical pieces are not presented in a standardized manner and some of the diseases that occur worldwide in humans need not be listed, such as the common cold or cholecystitis. In addition, some of the trend graphs show outdated data; readers need to look elsewhere for updated information regarding emerging or reemerging problems. Some of the graphs need careful examination as the reported number of cases of a disease per 100,000 population cannot be translated into the incidence—again, due to different countries’

reporting structures. Also, the number of cases of a disease reported may reflect not only indigenous cases within a country but also imported cases as well. Thus, the reader can be left confused by a trend graph of cases of clonorchis in Denmark or amebic colitis in the United States. Despite these shortcomings, the GIDEON e-Books are an encyclopedia of infectious diseases across countries worldwide. They are continually updated and represent the only texts of their kind. They complement the excellent GIDEON on-line diagnostic tool and are a great addition to a library for those practicing infectious diseases, public health, global health, and even primary care. “
“We present a recent case of Japanese encephalitis in a Danish male traveler to Cambodia, who we believe is the second Danish case within the last 15 years.

Taken together, AMPA receptors expressed in Purkinje cells are considered to be GluA1/GluA2 or GluA2/GluA3 heteromeric channels. In contrast, AMPA receptors lacking GluA2, such as GluA1/GluA3 heteromeric channels and GluA1 or GluA3 homomeric channels, are little expressed, if at all, in Purkinje cells. Notably, AMPA receptors remaining in γ-2-KO, γ-7-KO and DKO Purkinje cells all preserved the linear I-V relationship, even although GluA2 expression was significantly reduced in Purkinje cells of these KO mice. From these findings, it can be assumed that in Purkinje cells the ablation of γ-2 causes severe reduction in GluA2/GluA3 channels,

which results in severe reduction in AMPA receptor-mediated currents. The remaining GluA1/GluA2 channels probably mediate residual currents in γ-2-KO Purkinje cells. This large current deficit in γ-2-KO Purkinje

cells suggests that GluA2/GluA3 channels Selleckchem CDK inhibitor are the predominant channel in Purkinje cells. This possibility appears to be supported by consistently much lower density Target Selective Inhibitor Library of immunogold labeling for GluA1 than for GluA2 and GluA3 at the climbing fiber–Purkinje cell synapse (M. Fukaya, M. Yamasaki and M. Watanabe, unpublished observation). The large deficit may also reflect tonic enhancement of AMPA receptor channel function by γ-2 (Yamazaki et al., 2004; Kato et al., 2007, 2008). In contrast, similar levels of GluA1–GluA3 localization and AMPA receptor-mediated currents at γ-7-KO climbing fiber–Purkinje pheromone cell synapses suggest normal synaptic expression of GluA2/GluA3 and GluA1/GluA2 channels. By the ablation of both TARPs, however, GluA2/GluA3 channels are depleted almost completely and GluA1/GluA2 channels are also reduced substantially, leading to more severe deficits at all the biochemical, electrophysiological

and behavioral levels. In future studies, it would be intriguing to pursue whether such a subunit-dependent regulation by multiple TARPs plays a role in activity-dependent insertion, internalization and recycling of GluA1/GluA2 and GluA2/GluA3 channels. These are considered to be key mechanisms underlying the changes in synaptic strength observed during several forms of long-term potentiation and long-term depression (Shi et al., 2001; Malinow & Malenka, 2002; Song & Huganir, 2002; Lee et al., 2004). The synergistic promotion of synaptic GluA2–GluA4 expression by γ-2 and γ-7 was demonstrated reproducibly by Western blot, light microscopic immunohistochemistry and postembedding immunogold electron microscopy. By contrast, the lack of apparent reductions in synaptic localization of GluA1 and GluA4 in γ-7-KO mice (except for GluA4 at the mossy fiber–granule cell synapse) was inconsistent with their substantial reductions in cerebellar contents and immunohistochemical signals in the molecular layer. This discrepancy was explained by substaintal loss of GluA1 and GluA4 in Bergmann glia.

Taken together, AMPA receptors expressed in Purkinje cells are considered to be GluA1/GluA2 or GluA2/GluA3 heteromeric channels. In contrast, AMPA receptors lacking GluA2, such as GluA1/GluA3 heteromeric channels and GluA1 or GluA3 homomeric channels, are little expressed, if at all, in Purkinje cells. Notably, AMPA receptors remaining in γ-2-KO, γ-7-KO and DKO Purkinje cells all preserved the linear I-V relationship, even although GluA2 expression was significantly reduced in Purkinje cells of these KO mice. From these findings, it can be assumed that in Purkinje cells the ablation of γ-2 causes severe reduction in GluA2/GluA3 channels,

which results in severe reduction in AMPA receptor-mediated currents. The remaining GluA1/GluA2 channels probably mediate residual currents in γ-2-KO Purkinje cells. This large current deficit in γ-2-KO Purkinje

cells suggests that GluA2/GluA3 channels Alectinib datasheet are the predominant channel in Purkinje cells. This possibility appears to be supported by consistently much lower density U0126 solubility dmso of immunogold labeling for GluA1 than for GluA2 and GluA3 at the climbing fiber–Purkinje cell synapse (M. Fukaya, M. Yamasaki and M. Watanabe, unpublished observation). The large deficit may also reflect tonic enhancement of AMPA receptor channel function by γ-2 (Yamazaki et al., 2004; Kato et al., 2007, 2008). In contrast, similar levels of GluA1–GluA3 localization and AMPA receptor-mediated currents at γ-7-KO climbing fiber–Purkinje Dapagliflozin cell synapses suggest normal synaptic expression of GluA2/GluA3 and GluA1/GluA2 channels. By the ablation of both TARPs, however, GluA2/GluA3 channels are depleted almost completely and GluA1/GluA2 channels are also reduced substantially, leading to more severe deficits at all the biochemical, electrophysiological

and behavioral levels. In future studies, it would be intriguing to pursue whether such a subunit-dependent regulation by multiple TARPs plays a role in activity-dependent insertion, internalization and recycling of GluA1/GluA2 and GluA2/GluA3 channels. These are considered to be key mechanisms underlying the changes in synaptic strength observed during several forms of long-term potentiation and long-term depression (Shi et al., 2001; Malinow & Malenka, 2002; Song & Huganir, 2002; Lee et al., 2004). The synergistic promotion of synaptic GluA2–GluA4 expression by γ-2 and γ-7 was demonstrated reproducibly by Western blot, light microscopic immunohistochemistry and postembedding immunogold electron microscopy. By contrast, the lack of apparent reductions in synaptic localization of GluA1 and GluA4 in γ-7-KO mice (except for GluA4 at the mossy fiber–granule cell synapse) was inconsistent with their substantial reductions in cerebellar contents and immunohistochemical signals in the molecular layer. This discrepancy was explained by substaintal loss of GluA1 and GluA4 in Bergmann glia.

PCR products were digested with XhoI and BamHI and then introduced into the pET15b (Novagen) expression vector (pET15b-SpPyrH and pET15b-HiPyrH, Epigenetics Compound Library respectively). The sequences of the cloned DNA fragments were verified as the pyrH gene ORF of S. pneumoniae (GenBank accession nos. AE005672) and that of H. influenzae (GenBank accession nos. L42023) by DNA sequencing. Then, E. coli Rosetta-Gami B (DE3) was transformed

with pET15b-SpPyrH or pET15b-HiPyrH according to the manufacturer’s instructions. After the transformed Rosetta-Gami B (DE3) cells were cultivated at 37 °C for 3 h in 250 mL of LB broth containing 100 μg mL−1 of carbenicillin, 1 mM isopropyl β-d-thiogalactopyranoside (IPTG) was added and then further cultivated at 30 °C for 3–4 h. After centrifugation, the pellets (= cells) were resuspended in 10 mL of B-PER reagent (Thermo Fisher Scientific Inc.), incubated at room temperature for 30 min and then sonicated with Biorupter (COSMO BIO CO., LTD.). After the lysates were centrifuged

at 16 100 g for 15 min, the supernatants, including the recombinant PyrH proteins tagged with 6xHis at NH2-terminus, were transferred to a column and incubated for 1 h with 2 mL of Ni-NTA agarose (Life Technologies Japan Ltd.) resin slurry that had been equilibrated with B-PER reagent. The STA-9090 purchase resin was washed with 2 mL of Wash Buffer 1 (Thermo Fisher Scientific Inc.) three times and with 3 mL of Wash Buffer 2 (Thermo Fisher Scientific Inc.) twice. Finally, the target protein, either recombinant S. pneumoniae PyrH (SpPyrH) or H. influenzae PyrH (HiPyrH), was eluted in 6 mL of Elution Buffer (Thermo Fisher Scientific Inc.). Samples were ran on a sodium dodecyl sulphate–polyacrylamide gel electrophoresis,

and purity of the target protein was examined by Coomassie blue staining or immunoblotting with HRP conjugate anti-His antibody (Promega Corporation) followed by a chemiluminescence for assay (ECL plus; GE Healthcare). PyrH synthesizes UDP according to the following scheme: UMP + ATP to UDP + ADP. To determine UMP kinase activity in vitro, we examined the amount of residual substrate, ATP, after the reaction. The amount of ATP was measured using the luminescence-based ATP quantitative reagent, Kinase-Glo (Promega). The UMP kinase reaction and the following luciferase reaction were carried out in a white 96-well half area plate. SpPyrH (2.5 units per well) or HiPyrH (1.5 units per well) was mixed with 2% (v/v) of test inhibitor, which was diluted twofold serially in DMSO/MeOH (70/30 [v/v]), 50 mM Tris–HCl (pH 7.5), 50 mM KCl, 2 mM MgCl2, 0.2 mM UMP and 5 μM ATP in a total volume of 50 μL. After 2.5-h incubation at 30 °C, 50 μL of the Kinase-Glo Assay reagent was added to initiate the luciferase reaction and was incubated for 10 min at room temperature. The levels of luminescence were measured using an ARVO luminometer (Perkin Elmer Co., Ltd.) and expressed in relative luminescence units (RLU).

The aim of this project was to evaluate the impact of counselling of cardiology patients by a pharmacist prior to discharge through their satisfaction as well as knowledge about their medicines. Ethical approval was not required as this project was considered as service evaluation. To obtain accurate results, a ‘before and after’ study was designed, where a control period was initially completed where patients were counselled by nurses as per current practice, followed by the intervention period where patients were counselled by a pharmacist prior to discharge. One pharmacist was responsible for counselling

the patients in the intervention group. A questionnaire was used to obtain check details results. The first part of the questionnaire includes the validated Satisfaction with Information about Medicines Scale (SIMS) with the use of five-point Likert scale.3 Examples of the questions include ‘what is your medicine(s) called?’, and ‘what is your medicine(s) for?’ The second

part had questions to determine patients’ knowledge and their views about the service. A total of 94 patients were recruited; 48 patients in the control period, and 46 patients in the intervention group. The table below shows the satisfaction score for the information provided to patients about AZD6244 their medication. Mann–Whitney (U) test was used to determine whether there was any significant difference in opinion regarding the information provided in the two groups. There was a statistically significant difference between the responses of both groups (p < 0.05) for all the questions, indicating a significant increase in patients' knowledge about their medicines the intervention group. Table 1 The satisfaction scores for the information received about medicines, and standard deviation (SD)   Control group Intervention group Mean score Standard deviation (SD) Mean score Standard deviation (SD) The majority of the patients (73%) were aware

of the changes made to their medicine: Quinapyramine 61% of the control group, and 85% of the intervention group. The awareness of the patients in the intervention group of the changes in their medication was significantly more than the control group, U = 867.5, z = −2.313, and p = 0.021. Pharmacists can have a significant input into the discharge process through improving patients’ knowledge about medication. Better understanding about medicines will help improve adherence too. However, with the available resources it is not possible to provide patient counselling to all patients being discharged from hospital; therefore, prioritising patients who are at high risk to be counselled by the pharmacy team is important. It is also vital to ensure that nurses receive the appropriate training to provide an equal and acceptable amount of information about medication to all patients prior to discharge. 1. Picton, C.

1b, upper panel). Densitometry analysis of the levels of PCR products shows that wag31Mtb was expressed at GDC-0980 molecular weight a level 11-fold higher in H37Rv cells containing relMtb. As a control to ensure that equivalent amounts of cellular mRNA were subjected to reverse transcription, expression of a Rel-independent gene was examined. rRNA levels were not compared because rRNA is downregulated in the presence of Rel (Cashel et al., 1996). Instead, dnaJ-specific mRNA levels were compared between M. tuberculosis strains with and without relMtb (Fig. 1b, lower panel). dnaJ encodes for a chaperone-like protein (Yamada-Noda

et al., 2007). Our previous microarray studies showed that dnaJ is not differentially regulated by RelMtb in M. tuberculosis (Dahl et al., 2003), making the gene an appropriate control to ensure that equivalent levels of mRNA were harvested from H37Rv and H37RvΔrel cells. Collectively, these Western blot and RT-PCR analyses confirm that wag31Mtb is positively regulated by the stringent response in M. tuberculosis. The wag31Mtb gene

was further examined to see whether it was differentially regulated by Daporinad in vitro the stringent response in the surrogate mycobacterial host M. smegmatis. We previously inactivated the stringent response in M. smegmatis mc2155 to facilitate the study of M. tuberculosis genes suspected of being either positively or negatively regulated by Rel (Dahl et al., 2003, 2005). To determine whether the wag31Mtb gene was similarly regulated by the stringent response in M. smegmatis, the relative levels of Wag31Mtb

protein and wag31Mtb mRNA were examined in M. smegmatis Oxymatrine strains expressing the gene. Mycobacterium smegmatis strains containing either the vector pOLYG or pwag31Mtb were grown in Middlebrook 7H9 medium+hygromycin (50 μg mL−1) with shaking for 4 days with culture densities measured using a spectrophotometer. No differences were observed in the growth rates regardless of the strain or the presence of pwag31Mtb (data not shown). To examine gene expression, the levels of wag31Mtb protein and mRNA products were determined (Fig. 2). Densitometry readings of the Wag31Mtb-specific bands reveal a 1.4-fold increased level of this protein in M. smegmatis mc2155 cells compared with the isogenic ΔrelMsm strain. The anti-H37Rv polyclonal antibodies raised against M. tuberculosis cell lysates do not appear to recognize the Wag31 homolog in M. smegmatis, as evident by the absence of a corresponding 45 kDa band in cells containing the cloning vector pOLYG (Fig. 2a, lanes 1 and 2). The Wag31 proteins of M. tuberculosis and M. smegmatis share 79% identity and 87% similarity, and the essential wag31Msm gene can be successfully replaced by wag31Mtb (Mukherjee et al., 2009).

By manipulating the expression of possible downstream effectors of Dlx1, neuropilin-2 and p21-activated kinase 3, we provided evidence for the involvement of these two signaling molecules in Dlx1-dependent regulation of dendritic differentiation. Our experimental data support the idea that Dlx1 expression in developing interneurons specifically Epacadostat suppresses two important downstream regulators, leading to the characteristic morphology of Dlx1-expressing interneurons with less branched dendrites and few dendritic spines. “
“The diuretic bumetanide,

which acts by blocking the Na–K–Cl cotransporter (NKCC), is widely used to inhibit neuronal NKCC1, particularly when NKCC1 expression is abnormally increased in brain diseases such as epilepsy. However, bumetanide poorly penetrates into the brain and, in rodents, is rapidly eliminated because of extensive oxidation of its N-butyl sidechain, reducing the translational value of rodent experiments. Inhibition of oxidation by piperonyl butoxide (PBO) has previously been reported to increase the half-life and diuretic activity of bumetanide in rats. Here we studied whether inhibition of bumetanide metabolism by PBO also increases brain levels of bumetanide in rats, and whether this alters pharmacodynamic effects in the kindling model of epilepsy. Furthermore, we studied the effects Y-27632 molecular weight of PBO in mice. Mice eliminated bumetanide less rapidly than rats

(elimination half-life 47 min vs. 13 min). Pretreatment with PBO increased the half-life in mice to average values (70 min) previously determined in humans, and markedly elevated brain Farnesyltransferase levels of bumetanide. In rats, the increase in plasma and brain levels of bumetanide by PBO was less marked than in mice. PBO significantly increased the diuretic activity of bumetanide in rats and, less effectively, in mice. In epileptic mice, bumetanide (with PBO) did not suppress spontaneous seizures. In the rat kindling model, bumetanide (with or without PBO) did not exert anticonvulsant effects on fully kindled seizures, but dose-dependently altered kindling

development. These data indicate that PBO offers a simple means to enhance the translational properties of rodent experiments with bumetanide, particularly when using mice. “
“Huntington’s disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin (htt) gene. Neuropathology is most severe in the striatum and cerebral cortex. As mutant htt is ubiquitously expressed, it has not been possible to establish clear structure-to-function relationships for the clinical aspects. In the present study, we have injected recombinant adeno-associated viral vectors of serotype 5 (rAAV5) expressing an 853-amino-acid fragment of htt with either 79 (mutant) or 18 (wild-type) glutamines (Q) in the dorsal striatum of neonatal rats to achieve expression of htt in the forebrain.

By manipulating the expression of possible downstream effectors of Dlx1, neuropilin-2 and p21-activated kinase 3, we provided evidence for the involvement of these two signaling molecules in Dlx1-dependent regulation of dendritic differentiation. Our experimental data support the idea that Dlx1 expression in developing interneurons specifically Dasatinib clinical trial suppresses two important downstream regulators, leading to the characteristic morphology of Dlx1-expressing interneurons with less branched dendrites and few dendritic spines. “
“The diuretic bumetanide,

which acts by blocking the Na–K–Cl cotransporter (NKCC), is widely used to inhibit neuronal NKCC1, particularly when NKCC1 expression is abnormally increased in brain diseases such as epilepsy. However, bumetanide poorly penetrates into the brain and, in rodents, is rapidly eliminated because of extensive oxidation of its N-butyl sidechain, reducing the translational value of rodent experiments. Inhibition of oxidation by piperonyl butoxide (PBO) has previously been reported to increase the half-life and diuretic activity of bumetanide in rats. Here we studied whether inhibition of bumetanide metabolism by PBO also increases brain levels of bumetanide in rats, and whether this alters pharmacodynamic effects in the kindling model of epilepsy. Furthermore, we studied the effects TSA HDAC in vivo of PBO in mice. Mice eliminated bumetanide less rapidly than rats

(elimination half-life 47 min vs. 13 min). Pretreatment with PBO increased the half-life in mice to average values (70 min) previously determined in humans, and markedly elevated brain Methane monooxygenase levels of bumetanide. In rats, the increase in plasma and brain levels of bumetanide by PBO was less marked than in mice. PBO significantly increased the diuretic activity of bumetanide in rats and, less effectively, in mice. In epileptic mice, bumetanide (with PBO) did not suppress spontaneous seizures. In the rat kindling model, bumetanide (with or without PBO) did not exert anticonvulsant effects on fully kindled seizures, but dose-dependently altered kindling

development. These data indicate that PBO offers a simple means to enhance the translational properties of rodent experiments with bumetanide, particularly when using mice. “
“Huntington’s disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin (htt) gene. Neuropathology is most severe in the striatum and cerebral cortex. As mutant htt is ubiquitously expressed, it has not been possible to establish clear structure-to-function relationships for the clinical aspects. In the present study, we have injected recombinant adeno-associated viral vectors of serotype 5 (rAAV5) expressing an 853-amino-acid fragment of htt with either 79 (mutant) or 18 (wild-type) glutamines (Q) in the dorsal striatum of neonatal rats to achieve expression of htt in the forebrain.

, 2001; García-González et al., 2005). The atzR-atzDEF cluster is physically separated from the unstable region containing

atzA, atzB and atzC by two large gene clusters, which include the functions for the replication, segregation and conjugational transfer of pADP-1 (Martinez et al., 2001). Cya− (unable to degrade cyanuric acid) mutants arise due to the spontaneous loss of the complete pADP-1 plasmid, but independent loss of atzD, atzE or atzF is not detected, suggesting that these genes do not share the genetic instability of atzA, atzB and atzC (V. García-González & F. Govantes, unpublished data). Because atrazine is used primarily as a nitrogen source by degrading strains, the effect of nitrogen availability on atrazine degradation rates has been documented extensively. Generally, nitrogen amendments reduce the rates of atrazine degradation both in soil microbial populations (Entry et al., 1993; Alvey & Crowley, 1995; selleck Abdelhafid et al., 2000a, b; Guillén-Garcés et al., 2007) and in pure cultures of degrading bacteria (Bichat et al., 1999; Gebendinger & Radosevich, 1999; García-González et al., 2003), although exceptions to this rule

have been documented (Bichat et al., 1999). Pseudomonas sp. strain ADP is the best-characterized bacterial strain in nitrogen control of atrazine utilization (reviewed by Govantes et al., 2009). Atrazine selleck products degradation by resting cell suspensions of Pseudomonas sp. strain ADP is inhibited when cells are grown on nitrogen sources that support fast growth, whereas cells grown on growth-limiting nitrogen sources or metabolites of the pathway (including atrazine) Progesterone support efficient degradation. Atrazine does not induce the pathway in the presence of other nitrogen sources (Bichat et al.,

1999; García-González et al., 2003). Similarly, nitrate amendment significantly inhibited atrazine mineralization by Pseudomonas sp. strain ADP when tested in soil microcosms. The negative effect of added nitrogen sources on atrazine elimination limits the use of Pseudomonas sp. strain ADP bioremediation of atrazine-polluted agricultural soils (García-González et al., 2003). It should be noted that inhibition of atrazine metabolism by nitrate is only relevant when it is provided as a nitrogen source, as Pseudomonas sp. ADP appears to mineralize atrazine normally when nitrate is provided as an electron acceptor under anoxic conditions (Katz et al., 2000). This observation highlights the notion that inhibition is not the result of the mere presence of nitrate in the medium, but of its contribution to nitrogen availability. Attempts to study the expression of the atzA, atzB and atzC genes in Pseudomonas sp. strain ADP failed to demonstrate regulation in response to atrazine (Martinez et al., 2001; Devers et al., 2004) or nitrogen limitation (O. Porrúa & F. Govantes, unpublished data).