Ajit Shah - Academia.edu (original) (raw)
Papers by Ajit Shah
Journal of Neuroscience Methods, 2002
A high-throughput liquid chromatography tandem mass spectrometry (LC/MS/MS) method has been devel... more A high-throughput liquid chromatography tandem mass spectrometry (LC/MS/MS) method has been developed for the analysis of acetylcholine (ACh) in brain dialysates. This separation of ACh is based on cation exchange chromatography with elution buffer consisting of a mixture of ammonium acetate, ammonium formate and acetonitrile. Using isocratic separation conditions, ACh was resolved within a minute and detected using tandem mass
Synapse, 2009
A number of studies suggest that stressful conditions can induce structural alterations in the hi... more A number of studies suggest that stressful conditions can induce structural alterations in the hippocampus and that antidepressant drugs may prevent such deficits. In particular, the selective serotonin reuptake inhibitor (SSRI) fluoxetine was more effective in modulating different neuronal plasticity phenomena and related molecules in rat hippocampus. Cytoskeletal microtubule dynamics are fundamental to dendrites and axons remodeling, leading to the hypothesis that fluoxetine may affect the microtubular system. However, despite reports of stress-induced alterations in microtubule dynamics by different stressors, only few studies investigated the in vivo effects of antidepressants on microtubules in specific rat brain regions. The present study investigated the dose-related (1, 5, or 10 mg/kg i.p.) effects of acute and chronic (21 days) treatments with fluoxetine on the ratio of hippocampal a-tubulin isoforms which is thought to reflect microtubule dynamics. Western Blot analysis was used to quantify a-tubulin isoforms, high-performance liquid chromatography and fluorescence detection was used to measure ex vivo monoamine metabolism. The results showed that acute fluoxetine increased the stable forms acetylated and detyrosinated a-tubulin. Conversely, chronic fluoxetine decreased acetylated a-tubulin, indicative of increased microtubule dynamics. The neuron-specific D2-Tubulin was increased by chronic fluoxetine indicating neuronal involvement in the observed cytoskeletal changes. Although acute and chronic fluoxetine similarly altered serotonin metabolism by inhibition of serotonin reuptake, this showed no apparent correlation to the cytoskeletal perturbations. Our findings demonstrate that fluoxetine administration modulates microtubule dynamics in rat hippocampus. The cytoskeletal effect exerted by fluoxetine may eventually culminate in promoting events of structural neuronal remodeling. Synapse 63: 359-364, 2009. V
Neuropsychopharmacology, 2002
Recent neuroanatomical and functional investigations focusing on dopamine (DA) D 3 receptors have... more Recent neuroanatomical and functional investigations focusing on dopamine (DA) D 3 receptors have suggested a potential role of this receptor in psychiatric diseases such as schizophrenia and drug dependence. In line with the key role of the prefrontal cortex in psychiatric disorders, the present study aimed at assessing the effects of the acute systemic administration of the selective DA D 3 receptor antagonist SB-277011-A on the in vivo extracellular levels of monoamines (DA, norepinephrine (NE), and serotonin (5-HT)) and acetylcholine (ACh) in the anterior cingulate subregion of the medial prefrontal cortex. The in vivo neurochemical profile of SB-277011-A (10 mg/kg, i.p.) in the anterior cingulate cortex was compared with both typical and atypical antipsychotics including clozapine (10 mg/kg, s.c.), olanzapine (10 mg/kg, s.c.), sulpiride (10 mg/kg, s.c.), and haloperidol (0.5 mg/kg, s.c.). The acute administration of SB-277011-A, clozapine, and olanzapine produced a significant increase in extracellular levels of DA, NE, and ACh without affecting levels of 5-HT. Sulpiride also significantly increased extracellular DA, but with a delayed onset over SB-277011-A, clozapine, and olanzapine. In contrast, haloperidol failed to alter any of the three monoamines and ACh in the anterior cingulate cortex. These findings add to a growing body of evidence suggesting a differentiation between typical and atypical antipsychotic drugs (APDs) in the anterior cingulate cortex and a role of DA D 3 receptors in desired antipsychotic drug profile. Similar to their effects on DA and NE, SB-277011-A, clozapine, and olanzapine increased extracellular levels of ACh, whereas haloperidol and sulpiride did not alter ACh. The results obtained in the present study provide evidence of the important role of DA D 3 receptors in the effect of pharmacotherapeutic agents that are used for the treatment of psychiatric disorders such as schizophrenia and drug dependence.
Neuropharmacology, 2009
A group II metabotropic glutamate receptor (mGluR) agonist was recently reported to be clinically... more A group II metabotropic glutamate receptor (mGluR) agonist was recently reported to be clinically efficacious against symptoms of schizophrenia [Patil, S.T., Zhang, L., Martenyi, F., Lowe, S.L., Jackson, K.A., Andreev, B.V., Avedisova, A.S., Bardenstein, L.M., Gurovich, I.Y., Morozova, M.A., Mosolov, S.N., Neznanov, N.G., Reznik, A.M., Smulevich, A.B., Tochilov, V.A., Johnson, B.G., Monn, J.A., Schoepp, D.D., 2007. Activation of mGlu2/3 receptors as a new approach to treat schizophrenia: a randomized phase 2 clinical trial. Nature Med 13, 1102-1107]. The endogenous neuropeptide N-acetylaspartylglutamate (NAAG) has been described as an agonist at mGluR2 and mGluR3 [Wroblewska, B., Wroblewski, J.T., Pshenichkin, S., Surin, A., Sullivan, S.E., Neale, J.H., 1997. N-acetylaspartylglutamate selectively activates mGluR3 receptors in transfected cells. J. Neurochem. 69, 174-181; Cartmell, J., Adam, G., Chaboz, S., Henningsen, R., Kemp, J.A., Klingelschmidt, A., Metzler, V., Monsma, F., Schaffhauser, H., Wichmann, J., Mutel, V., 1998. Characterization of [3H]-(2S,2'R,3'R)-2-(2',3'-dicarboxy-cyclopropyl)glycine ([3H]-DCG IV) binding to metabotropic mGlu2 receptor-transfected cell membranes. Br. J. Pharmacol. 123, 497-504] and is degraded by the enzyme glutamate carboxypeptidase II (also known as N-acetyl-alpha-linked acidic dipeptidase or NAALADase). Hence, elevating the concentration of endogenous NAAG by inhibition of NAALADase represents a potential strategy for the treatment of schizophrenia via group II mGluR activation. We therefore investigated the activity of NAAG at both rat native and human recombinant mGluRs. We found that NAAG had no effect on synaptic transmission at the medial perforant pathway inputs to the rat dentate gyrus which is known to be sensitive to group II mGluR activation. We proceeded to examine the effects of NAAG at human recombinant mGluR2 and mGluR3 in a cellular G protein-activated K+ channel electrophysiology assay. Furthermore, due to discrepancies in the literature concerning the activity of NAAG at the N-methyl-d-aspartate receptor [NMDAR; Westbrook, G.L., Mayer, M.L., Namboodiri, M.A., Neale, J.H., 1986. High concentrations of N-acetylaspartylglutamate (NAAG) selectively activate NMDA receptors on mouse spinal cord neurons in cell culture. J. Neurosci. 6, 3385-3392; Losi, G., Vicini, S., Neale, J., 2004. NAAG fails to antagonize synaptic and extrasynaptic NMDA receptors in cerebellar granule neurons. Neuropharmacology 46, 490-496], we also tested NAAG at NMDARs in rat hippocampal neurons in culture. We found that a purified NAAG preparation had no effect at mGluR2, mGluR3 or NMDAR. Taken together, these findings do not support a rationale for targeting NAALADase and increasing extracellular NAAG levels as a therapeutic strategy for the treatment of schizophrenia.
Journal of Chromatography B, 2008
A liquid chromatography-tandem mass spectrometric method has been developed for measurement of N-... more A liquid chromatography-tandem mass spectrometric method has been developed for measurement of N-acetylaspartate, N-acetylaspartylglutamate and glutamate. The analytes were separated within 5 min using an anion exchange/reverse phase column. The lower limit of quantification for Glu, NAA and NAAG was found to be 5, 50 and 6 nM, respectively, with a signal-to-noise ratio of 5:1. Using this methodology the basal levels of Glu, NAA and NAAG could be measured consistently in in vitro superfusion samples from rat hippocampus. The assay was also used for measurement of the distribution of Glu, NAA and NAAG in different regions of the rat brain.
Journal of Chromatography B, 2002
Amino acids in the central nervous system can be divided into non-neurotransmitter or neurotransm... more Amino acids in the central nervous system can be divided into non-neurotransmitter or neurotransmitter depending on their function. The measurement of these small molecules in brain tissue and extracellular fluid has been used to develop effective treatment strategies for neuropsychiatric and neurodegenerative diseases and for the diagnosis of such pathologies. Here we describe the separation and detection techniques that have been used for the measurement of amino acids at trace levels in brain tissue and dialysates. An overview of the function of amino acid transmitters in the brain is given. In addition, the type of sampling techniques that are used for the determination of amino acid levels in the brain is described.
International Psychogeriatrics, 2008
... Hospital and Community Psychiatry, 39, 822–823. Anthony, JC and Helzer, JE (1991). Syndromes ... more ... Hospital and Community Psychiatry, 39, 822–823. Anthony, JC and Helzer, JE (1991). Syndromes of drug abuse and dependence. ... American Journal of Geriatric Psychiatry, 13, 385–392. Atkinson, RM and Kofoed, LL (1982). ...
International Psychogeriatrics, 2000
Aggressive behavior is common in nursing homes for the elderly. It causes distress to carers and ... more Aggressive behavior is common in nursing homes for the elderly. It causes distress to carers and can lead to hospitalization, overmedication, and physical restraint. A 6-month prospective study examining the characteristics of aggressive subjects in 11 nursing homes in Melbourne using validated, reliable instruments. During the study, 121 and 143 subjects were rated aggressive on the Rating Scale for Aggressive Behavior in the Elderly and the Staff Observation Aggression Scale, respectively. Aggressive behavior was associated with younger age, men, subsequent mortality, and prescription of psychotropic drugs including neuroleptics, antidepressants, and benzodiazepines. Educational programs in the use of psychotropic drugs directed at staff involved in the care of nursing home residents may be of value because these drugs have modest efficacy, have significant side effects, and may simply sedate the patient rather than treat aggressive behavior.
European Neuropsychopharmacology, 2009
Social isolation from weaning in rats produces behavioural and hippocampal structural changes at ... more Social isolation from weaning in rats produces behavioural and hippocampal structural changes at adulthood. Here, rats were group or isolation reared for eight-weeks. Following the initial fourweek period of rearing, fluoxetine (10 mg/kg i.p.) was administered for 28 days. Changes in recognition memory, hippocampal monoamines, and cytoskeletal microtubules were investigated. Isolation-rearing for four-or eight-weeks produced recognition memory deficits that were not reversed by fluoxetine. Eight-weeks of isolation decreased α-tubulin acetylation (Acet-Tub) and the tyrosinated/detyrosinated α-tubulin ratio (Tyr/Glu-Tub), suggesting major alterations in microtubule dynamics and neuronal plasticity. In grouped rats, fluoxetine decreased Acet-Tub without changes in Tyr/Glu-Tub. In isolates, fluoxetine did not affect Acet-Tub but increased Tyr/ Glu-Tub. Finally, fluoxetine altered serotonin metabolism in grouped, but not in isolated animals. Therefore, isolation-rearing changes the hippocampal responses of the serotonergic and microtubular system to fluoxetine. These findings show that early-life experience induces behavioural changes paralleled by alterations in cytoskeletal and neurochemical functions.
BMC Cell Biology, 2009
The phosphoinositide (PIns) signalling pathway regulates a series of neuronal processes, such as ... more The phosphoinositide (PIns) signalling pathway regulates a series of neuronal processes, such as neurotransmitter release, that are thought to be altered in mood disorders. Furthermore, mood-stabilising drugs have been shown to inhibit key enzymes that regulate PIns production and alter neuronal growth cone morphology in an inositol-reversible manner. Here, we describe analyses of expression and function of the recently identified H + /myo-inositol transporter (HMIT) investigated as a potential regulator of PIns signalling.
Journal of Agricultural Engineering Research, 1985
A high precision weighing lysimeter for measuring evapotranspiration in greenhouses was developed... more A high precision weighing lysimeter for measuring evapotranspiration in greenhouses was developed. The instrument has a measurement of sensitivity of one part in 106, that is one order of magnitude better than any other so far described in the literature. With it, evaporation rates in a greenhouse, even at night, can be measured on a one minute time scale. Development and construction of the instrument are described and measurements of the transpiration of a tomato crop in a greenhouse are used to demonstrate its capabilities.
Behavioural Pharmacology, 2004
Analytica Chimica Acta, 2004
International psychogeriatrics / IPA, Jan 24, 2015
A wish to die is common in older persons and is associated with increased mortality. Several risk... more A wish to die is common in older persons and is associated with increased mortality. Several risk factors have been identified, but the association between religiousness and a wish to die in older adults has been underexplored, and the association between death attitudes and the presence of a wish to die has not been investigated yet. The aim of this study is to explore the relationship between religiousness and death attitudes on the one hand and wish to die on the other hand, adjusting for clinical factors such as the presence of depression or somatic disorder. The sample comprised 113 older inpatients (from a psychiatric and somatic ward) with a mean age of 74 years. Psychiatric diagnoses were assessed by the Structured Clinical Interview for DSM-IV Disorders, and logistic regression analyses estimated the unique contribution of religiousness and death attitudes to the wish to die, controlling for socio-demographic variables, depressive disorder, and somatic symptoms. Both religi...
International Psychogeriatrics
ABSTRACT Background: Death wishes are not uncommon in older persons, and to date, several risk fa... more ABSTRACT Background: Death wishes are not uncommon in older persons, and to date, several risk factors have been identified. The presence of these risk factors is insufficient to fully understand why some older people, who are exposed to them, develop a wish to die and why others do not. The purpose of the study was to explore whether Purpose in Life as well as other life attitudes are associated with a death wish in older males and females. Methods: The sample comprised 113 older inpatients (from a psychiatric and somatic ward) with a mean age of 74 years. Psychiatric diagnoses were assessed by the SCID-II. Logistic regression analyses estimated the unique contribution of (the interaction between) life attitudes and gender to the wish to die, controlling for sociodemographic variables, depressive disorder, and somatic symptoms. Results: We observed a statistically significant relationship between life attitudes and the wish to die. Purpose in Life and the Purpose in Life*Gender int...
This article considers the effectiveness of two one-day events designed to raise awareness of The... more This article considers the effectiveness of two one-day events designed to raise awareness of The Mental Capacity Act 2005 (MCA) in BME communities. The events were held using specially developed materials and were evaluated with the help of a 12-item questionnaire. The results of the evaluation showed that there was an increase in the proportion of correct responses for 10 of the 12 questions after attending awareness-raising events. The total score for all correct responses on the 12-item questionnaire significantly increased after attending the awareness-raising events. Collectively, the findings suggest that the awareness-raising events were able to improve awareness of the MCA among representatives of BME communities. Such awareness-raising events should be encouraged by health and social care providers
The Mental Capacity Act 2005 (MCA) was fully implemented in October 2007 in England and Wales. Th... more The Mental Capacity Act 2005 (MCA) was fully implemented in October 2007 in England and Wales. This article reports on two similar, but separate, pilot questionnaire studies that examined the experience of consultants in old age psychiatry and consultants in other psychiatric specialities in the early implementation of the MCA pertaining to issues relevant to black and minority ethnic (BME) groups. Fifty-two (27%) of the 196 consultants in old age psychiatry and 113 (12%) of the 955 consultants in other psychiatric specialities returned useable questionnaires. Eighty per cent or more of the consultants in old age psychiatry and consultants in other psychiatric specialities gave consideration to religion and culture and ethnicity in the assessment of decision-making capacity (DMC). Almost 50% of the consultants in old age psychiatry reported that half or more of the patients lacking fluency in English or where English was not their first language received an assessment of DMC with th...
Aging & mental health, Jan 22, 2015
There is paucity of studies examining suicide rates in narrow five-year age-bands after the age o... more There is paucity of studies examining suicide rates in narrow five-year age-bands after the age of 60 years. This study examined suicide rates in eight five-year age-bands between the age of 60 and 99 years because this will allow more precise comparison between the young old (60-79 years) and the oldest old (80+ years) age groups. Data on the number of suicides (International Classification of Diseases - ICD-10 codes, X60-84) in each of the eight five-year age-bands between the age-bands 60-64 years and 95-99 years in both gender for as many years as possible from 2000 were ascertained from three sources: colleagues with access to national data, national statisics office websites and email contact with the national statistics offices. The population size for the corresponding years and age-bands was estimated for each country using data provided by the United Nations website. In men, suicide rates continued to increase for each of the seven five-year age-bands from 60-64 years to 9...
Journal of Neuroscience Methods, 2002
A high-throughput liquid chromatography tandem mass spectrometry (LC/MS/MS) method has been devel... more A high-throughput liquid chromatography tandem mass spectrometry (LC/MS/MS) method has been developed for the analysis of acetylcholine (ACh) in brain dialysates. This separation of ACh is based on cation exchange chromatography with elution buffer consisting of a mixture of ammonium acetate, ammonium formate and acetonitrile. Using isocratic separation conditions, ACh was resolved within a minute and detected using tandem mass
Synapse, 2009
A number of studies suggest that stressful conditions can induce structural alterations in the hi... more A number of studies suggest that stressful conditions can induce structural alterations in the hippocampus and that antidepressant drugs may prevent such deficits. In particular, the selective serotonin reuptake inhibitor (SSRI) fluoxetine was more effective in modulating different neuronal plasticity phenomena and related molecules in rat hippocampus. Cytoskeletal microtubule dynamics are fundamental to dendrites and axons remodeling, leading to the hypothesis that fluoxetine may affect the microtubular system. However, despite reports of stress-induced alterations in microtubule dynamics by different stressors, only few studies investigated the in vivo effects of antidepressants on microtubules in specific rat brain regions. The present study investigated the dose-related (1, 5, or 10 mg/kg i.p.) effects of acute and chronic (21 days) treatments with fluoxetine on the ratio of hippocampal a-tubulin isoforms which is thought to reflect microtubule dynamics. Western Blot analysis was used to quantify a-tubulin isoforms, high-performance liquid chromatography and fluorescence detection was used to measure ex vivo monoamine metabolism. The results showed that acute fluoxetine increased the stable forms acetylated and detyrosinated a-tubulin. Conversely, chronic fluoxetine decreased acetylated a-tubulin, indicative of increased microtubule dynamics. The neuron-specific D2-Tubulin was increased by chronic fluoxetine indicating neuronal involvement in the observed cytoskeletal changes. Although acute and chronic fluoxetine similarly altered serotonin metabolism by inhibition of serotonin reuptake, this showed no apparent correlation to the cytoskeletal perturbations. Our findings demonstrate that fluoxetine administration modulates microtubule dynamics in rat hippocampus. The cytoskeletal effect exerted by fluoxetine may eventually culminate in promoting events of structural neuronal remodeling. Synapse 63: 359-364, 2009. V
Neuropsychopharmacology, 2002
Recent neuroanatomical and functional investigations focusing on dopamine (DA) D 3 receptors have... more Recent neuroanatomical and functional investigations focusing on dopamine (DA) D 3 receptors have suggested a potential role of this receptor in psychiatric diseases such as schizophrenia and drug dependence. In line with the key role of the prefrontal cortex in psychiatric disorders, the present study aimed at assessing the effects of the acute systemic administration of the selective DA D 3 receptor antagonist SB-277011-A on the in vivo extracellular levels of monoamines (DA, norepinephrine (NE), and serotonin (5-HT)) and acetylcholine (ACh) in the anterior cingulate subregion of the medial prefrontal cortex. The in vivo neurochemical profile of SB-277011-A (10 mg/kg, i.p.) in the anterior cingulate cortex was compared with both typical and atypical antipsychotics including clozapine (10 mg/kg, s.c.), olanzapine (10 mg/kg, s.c.), sulpiride (10 mg/kg, s.c.), and haloperidol (0.5 mg/kg, s.c.). The acute administration of SB-277011-A, clozapine, and olanzapine produced a significant increase in extracellular levels of DA, NE, and ACh without affecting levels of 5-HT. Sulpiride also significantly increased extracellular DA, but with a delayed onset over SB-277011-A, clozapine, and olanzapine. In contrast, haloperidol failed to alter any of the three monoamines and ACh in the anterior cingulate cortex. These findings add to a growing body of evidence suggesting a differentiation between typical and atypical antipsychotic drugs (APDs) in the anterior cingulate cortex and a role of DA D 3 receptors in desired antipsychotic drug profile. Similar to their effects on DA and NE, SB-277011-A, clozapine, and olanzapine increased extracellular levels of ACh, whereas haloperidol and sulpiride did not alter ACh. The results obtained in the present study provide evidence of the important role of DA D 3 receptors in the effect of pharmacotherapeutic agents that are used for the treatment of psychiatric disorders such as schizophrenia and drug dependence.
Neuropharmacology, 2009
A group II metabotropic glutamate receptor (mGluR) agonist was recently reported to be clinically... more A group II metabotropic glutamate receptor (mGluR) agonist was recently reported to be clinically efficacious against symptoms of schizophrenia [Patil, S.T., Zhang, L., Martenyi, F., Lowe, S.L., Jackson, K.A., Andreev, B.V., Avedisova, A.S., Bardenstein, L.M., Gurovich, I.Y., Morozova, M.A., Mosolov, S.N., Neznanov, N.G., Reznik, A.M., Smulevich, A.B., Tochilov, V.A., Johnson, B.G., Monn, J.A., Schoepp, D.D., 2007. Activation of mGlu2/3 receptors as a new approach to treat schizophrenia: a randomized phase 2 clinical trial. Nature Med 13, 1102-1107]. The endogenous neuropeptide N-acetylaspartylglutamate (NAAG) has been described as an agonist at mGluR2 and mGluR3 [Wroblewska, B., Wroblewski, J.T., Pshenichkin, S., Surin, A., Sullivan, S.E., Neale, J.H., 1997. N-acetylaspartylglutamate selectively activates mGluR3 receptors in transfected cells. J. Neurochem. 69, 174-181; Cartmell, J., Adam, G., Chaboz, S., Henningsen, R., Kemp, J.A., Klingelschmidt, A., Metzler, V., Monsma, F., Schaffhauser, H., Wichmann, J., Mutel, V., 1998. Characterization of [3H]-(2S,2'R,3'R)-2-(2',3'-dicarboxy-cyclopropyl)glycine ([3H]-DCG IV) binding to metabotropic mGlu2 receptor-transfected cell membranes. Br. J. Pharmacol. 123, 497-504] and is degraded by the enzyme glutamate carboxypeptidase II (also known as N-acetyl-alpha-linked acidic dipeptidase or NAALADase). Hence, elevating the concentration of endogenous NAAG by inhibition of NAALADase represents a potential strategy for the treatment of schizophrenia via group II mGluR activation. We therefore investigated the activity of NAAG at both rat native and human recombinant mGluRs. We found that NAAG had no effect on synaptic transmission at the medial perforant pathway inputs to the rat dentate gyrus which is known to be sensitive to group II mGluR activation. We proceeded to examine the effects of NAAG at human recombinant mGluR2 and mGluR3 in a cellular G protein-activated K+ channel electrophysiology assay. Furthermore, due to discrepancies in the literature concerning the activity of NAAG at the N-methyl-d-aspartate receptor [NMDAR; Westbrook, G.L., Mayer, M.L., Namboodiri, M.A., Neale, J.H., 1986. High concentrations of N-acetylaspartylglutamate (NAAG) selectively activate NMDA receptors on mouse spinal cord neurons in cell culture. J. Neurosci. 6, 3385-3392; Losi, G., Vicini, S., Neale, J., 2004. NAAG fails to antagonize synaptic and extrasynaptic NMDA receptors in cerebellar granule neurons. Neuropharmacology 46, 490-496], we also tested NAAG at NMDARs in rat hippocampal neurons in culture. We found that a purified NAAG preparation had no effect at mGluR2, mGluR3 or NMDAR. Taken together, these findings do not support a rationale for targeting NAALADase and increasing extracellular NAAG levels as a therapeutic strategy for the treatment of schizophrenia.
Journal of Chromatography B, 2008
A liquid chromatography-tandem mass spectrometric method has been developed for measurement of N-... more A liquid chromatography-tandem mass spectrometric method has been developed for measurement of N-acetylaspartate, N-acetylaspartylglutamate and glutamate. The analytes were separated within 5 min using an anion exchange/reverse phase column. The lower limit of quantification for Glu, NAA and NAAG was found to be 5, 50 and 6 nM, respectively, with a signal-to-noise ratio of 5:1. Using this methodology the basal levels of Glu, NAA and NAAG could be measured consistently in in vitro superfusion samples from rat hippocampus. The assay was also used for measurement of the distribution of Glu, NAA and NAAG in different regions of the rat brain.
Journal of Chromatography B, 2002
Amino acids in the central nervous system can be divided into non-neurotransmitter or neurotransm... more Amino acids in the central nervous system can be divided into non-neurotransmitter or neurotransmitter depending on their function. The measurement of these small molecules in brain tissue and extracellular fluid has been used to develop effective treatment strategies for neuropsychiatric and neurodegenerative diseases and for the diagnosis of such pathologies. Here we describe the separation and detection techniques that have been used for the measurement of amino acids at trace levels in brain tissue and dialysates. An overview of the function of amino acid transmitters in the brain is given. In addition, the type of sampling techniques that are used for the determination of amino acid levels in the brain is described.
International Psychogeriatrics, 2008
... Hospital and Community Psychiatry, 39, 822–823. Anthony, JC and Helzer, JE (1991). Syndromes ... more ... Hospital and Community Psychiatry, 39, 822–823. Anthony, JC and Helzer, JE (1991). Syndromes of drug abuse and dependence. ... American Journal of Geriatric Psychiatry, 13, 385–392. Atkinson, RM and Kofoed, LL (1982). ...
International Psychogeriatrics, 2000
Aggressive behavior is common in nursing homes for the elderly. It causes distress to carers and ... more Aggressive behavior is common in nursing homes for the elderly. It causes distress to carers and can lead to hospitalization, overmedication, and physical restraint. A 6-month prospective study examining the characteristics of aggressive subjects in 11 nursing homes in Melbourne using validated, reliable instruments. During the study, 121 and 143 subjects were rated aggressive on the Rating Scale for Aggressive Behavior in the Elderly and the Staff Observation Aggression Scale, respectively. Aggressive behavior was associated with younger age, men, subsequent mortality, and prescription of psychotropic drugs including neuroleptics, antidepressants, and benzodiazepines. Educational programs in the use of psychotropic drugs directed at staff involved in the care of nursing home residents may be of value because these drugs have modest efficacy, have significant side effects, and may simply sedate the patient rather than treat aggressive behavior.
European Neuropsychopharmacology, 2009
Social isolation from weaning in rats produces behavioural and hippocampal structural changes at ... more Social isolation from weaning in rats produces behavioural and hippocampal structural changes at adulthood. Here, rats were group or isolation reared for eight-weeks. Following the initial fourweek period of rearing, fluoxetine (10 mg/kg i.p.) was administered for 28 days. Changes in recognition memory, hippocampal monoamines, and cytoskeletal microtubules were investigated. Isolation-rearing for four-or eight-weeks produced recognition memory deficits that were not reversed by fluoxetine. Eight-weeks of isolation decreased α-tubulin acetylation (Acet-Tub) and the tyrosinated/detyrosinated α-tubulin ratio (Tyr/Glu-Tub), suggesting major alterations in microtubule dynamics and neuronal plasticity. In grouped rats, fluoxetine decreased Acet-Tub without changes in Tyr/Glu-Tub. In isolates, fluoxetine did not affect Acet-Tub but increased Tyr/ Glu-Tub. Finally, fluoxetine altered serotonin metabolism in grouped, but not in isolated animals. Therefore, isolation-rearing changes the hippocampal responses of the serotonergic and microtubular system to fluoxetine. These findings show that early-life experience induces behavioural changes paralleled by alterations in cytoskeletal and neurochemical functions.
BMC Cell Biology, 2009
The phosphoinositide (PIns) signalling pathway regulates a series of neuronal processes, such as ... more The phosphoinositide (PIns) signalling pathway regulates a series of neuronal processes, such as neurotransmitter release, that are thought to be altered in mood disorders. Furthermore, mood-stabilising drugs have been shown to inhibit key enzymes that regulate PIns production and alter neuronal growth cone morphology in an inositol-reversible manner. Here, we describe analyses of expression and function of the recently identified H + /myo-inositol transporter (HMIT) investigated as a potential regulator of PIns signalling.
Journal of Agricultural Engineering Research, 1985
A high precision weighing lysimeter for measuring evapotranspiration in greenhouses was developed... more A high precision weighing lysimeter for measuring evapotranspiration in greenhouses was developed. The instrument has a measurement of sensitivity of one part in 106, that is one order of magnitude better than any other so far described in the literature. With it, evaporation rates in a greenhouse, even at night, can be measured on a one minute time scale. Development and construction of the instrument are described and measurements of the transpiration of a tomato crop in a greenhouse are used to demonstrate its capabilities.
Behavioural Pharmacology, 2004
Analytica Chimica Acta, 2004
International psychogeriatrics / IPA, Jan 24, 2015
A wish to die is common in older persons and is associated with increased mortality. Several risk... more A wish to die is common in older persons and is associated with increased mortality. Several risk factors have been identified, but the association between religiousness and a wish to die in older adults has been underexplored, and the association between death attitudes and the presence of a wish to die has not been investigated yet. The aim of this study is to explore the relationship between religiousness and death attitudes on the one hand and wish to die on the other hand, adjusting for clinical factors such as the presence of depression or somatic disorder. The sample comprised 113 older inpatients (from a psychiatric and somatic ward) with a mean age of 74 years. Psychiatric diagnoses were assessed by the Structured Clinical Interview for DSM-IV Disorders, and logistic regression analyses estimated the unique contribution of religiousness and death attitudes to the wish to die, controlling for socio-demographic variables, depressive disorder, and somatic symptoms. Both religi...
International Psychogeriatrics
ABSTRACT Background: Death wishes are not uncommon in older persons, and to date, several risk fa... more ABSTRACT Background: Death wishes are not uncommon in older persons, and to date, several risk factors have been identified. The presence of these risk factors is insufficient to fully understand why some older people, who are exposed to them, develop a wish to die and why others do not. The purpose of the study was to explore whether Purpose in Life as well as other life attitudes are associated with a death wish in older males and females. Methods: The sample comprised 113 older inpatients (from a psychiatric and somatic ward) with a mean age of 74 years. Psychiatric diagnoses were assessed by the SCID-II. Logistic regression analyses estimated the unique contribution of (the interaction between) life attitudes and gender to the wish to die, controlling for sociodemographic variables, depressive disorder, and somatic symptoms. Results: We observed a statistically significant relationship between life attitudes and the wish to die. Purpose in Life and the Purpose in Life*Gender int...
This article considers the effectiveness of two one-day events designed to raise awareness of The... more This article considers the effectiveness of two one-day events designed to raise awareness of The Mental Capacity Act 2005 (MCA) in BME communities. The events were held using specially developed materials and were evaluated with the help of a 12-item questionnaire. The results of the evaluation showed that there was an increase in the proportion of correct responses for 10 of the 12 questions after attending awareness-raising events. The total score for all correct responses on the 12-item questionnaire significantly increased after attending the awareness-raising events. Collectively, the findings suggest that the awareness-raising events were able to improve awareness of the MCA among representatives of BME communities. Such awareness-raising events should be encouraged by health and social care providers
The Mental Capacity Act 2005 (MCA) was fully implemented in October 2007 in England and Wales. Th... more The Mental Capacity Act 2005 (MCA) was fully implemented in October 2007 in England and Wales. This article reports on two similar, but separate, pilot questionnaire studies that examined the experience of consultants in old age psychiatry and consultants in other psychiatric specialities in the early implementation of the MCA pertaining to issues relevant to black and minority ethnic (BME) groups. Fifty-two (27%) of the 196 consultants in old age psychiatry and 113 (12%) of the 955 consultants in other psychiatric specialities returned useable questionnaires. Eighty per cent or more of the consultants in old age psychiatry and consultants in other psychiatric specialities gave consideration to religion and culture and ethnicity in the assessment of decision-making capacity (DMC). Almost 50% of the consultants in old age psychiatry reported that half or more of the patients lacking fluency in English or where English was not their first language received an assessment of DMC with th...
Aging & mental health, Jan 22, 2015
There is paucity of studies examining suicide rates in narrow five-year age-bands after the age o... more There is paucity of studies examining suicide rates in narrow five-year age-bands after the age of 60 years. This study examined suicide rates in eight five-year age-bands between the age of 60 and 99 years because this will allow more precise comparison between the young old (60-79 years) and the oldest old (80+ years) age groups. Data on the number of suicides (International Classification of Diseases - ICD-10 codes, X60-84) in each of the eight five-year age-bands between the age-bands 60-64 years and 95-99 years in both gender for as many years as possible from 2000 were ascertained from three sources: colleagues with access to national data, national statisics office websites and email contact with the national statistics offices. The population size for the corresponding years and age-bands was estimated for each country using data provided by the United Nations website. In men, suicide rates continued to increase for each of the seven five-year age-bands from 60-64 years to 9...