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Duchowski AT, Marmitt G, Desai R, Gramopadhye AK, Greenstein JS. Algorithm for comparison of 3D scanpaths in virtual reality. J Vis 2010. [DOI: 10.1167/3.9.311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Sarode SC, Zarkar GA, Kulkarni MA, Desai R. Role of forensic odontology in the world's major mass disasters: facts and figures. SADJ : JOURNAL OF THE SOUTH AFRICAN DENTAL ASSOCIATION = TYDSKRIF VAN DIE SUID-AFRIKAANSE TANDHEELKUNDIGE VERENIGING 2009; 64:388-393. [PMID: 20411832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
UNLABELLED Forensic identification of the victims in mass disasters is essential, not only for humanitarian reasons, but also for civil or criminal investigative need. The number of victims identified with the help of forensic odontology in various mass disasters in the world has been analysed and discussed. The result depicts the necessity of keeping proper dental records at institutional and individual level. Thus the use of forensic odontology in a series of mass disasters has been explored. The most common aspect of forensic odontology that a general practitioner is likely to encounter is the supply of ante-mortem records to aid in human identification. CLINICAL RELEVANCE The need for proper dental record-keeping by general dental practitioners is highlighted by discussing the role of forensic odontology in some of the world's major mass disasters.
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Jialal I, Desai R, Rajput MC. The effect of oestrogen priming on prolactin secretion in Sheehan's syndrome. J OBSTET GYNAECOL 2009. [DOI: 10.3109/01443618709008793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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79
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Desai R, Hussain M, Ruthven DM. Adsorption of water vapour on activated alumina. I -- equilibrium behaviour. CAN J CHEM ENG 2009. [DOI: 10.1002/cjce.5450700412] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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80
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Desai R, Hussain M, Ruthven DM. Adsorption on activated alumina. II - kinetic behaviour. CAN J CHEM ENG 2009. [DOI: 10.1002/cjce.5450700413] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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81
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Kaushalya SK, Desai R, Arumugam S, Ghosh H, Balaji J, Maiti S. Three-photon microscopy shows that somatic release can be a quantitatively significant component of serotonergic neurotransmission in the mammalian brain. J Neurosci Res 2009; 86:3469-80. [PMID: 18709651 DOI: 10.1002/jnr.21794] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Recent experiments on monoaminergic neurons have shown that neurotransmission can originate from somatic release. However, little is known about the quantity of monoamine available to be released through this extrasynaptic pathway or about the intracellular dynamics that mediate such release. Using three-photon microscopy, we directly imaged serotonin autofluorescence and investigated the total serotonin content, release competence, and release kinetics of somatic serotonergic vesicles in the dorsal raphe neurons of the rat. We found that the somata of primary cultured neurons contain a large number of serotonin-filled vesicles arranged in a perinuclear fashion. A similar distribution is also observed in fresh tissue slice preparations obtained from the rat dorsal raphe. We estimate that the soma of a cultured neuron on an average contains about 9 fmoles of serotonin in about 450 vesicles (or vesicle clusters) of < or =370 nm average diameter. A substantial fraction (>30%) of this serotonin is released with a time scale of several minutes by K(+)-induced depolarization or by para-chloroamphetamine treatment. The amount of releasable serotonin stored in the somatic vesicles is comparable to the total serotonin content of all the synaptic vesicles in a raphe neuron, indicating that somatic release can potentially play a major role in serotonergic neurotransmission in the mammalian brain.
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82
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Gupta V, Dhawan N, Saeed O, Bhoi S, Desai R, Verma S. 196: Impact of Health Education Video Intervention on Patient Knowledge in Emergency Department Waiting Area of a Developing Nation: A Pilot Study. Ann Emerg Med 2008. [DOI: 10.1016/j.annemergmed.2008.06.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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83
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Stewart D, Desai R, Cheng Q, Liu A, Forman SA. Tryptophan mutations at azi-etomidate photo-incorporation sites on alpha1 or beta2 subunits enhance GABAA receptor gating and reduce etomidate modulation. Mol Pharmacol 2008; 74:1687-95. [PMID: 18805938 DOI: 10.1124/mol.108.050500] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The potent general anesthetic etomidate produces its effects by enhancing GABA(A) receptor activation. Its photolabel analog [(3)H]azi-etomidate labels residues within transmembrane domains on alpha and beta subunits: alphaMet236 and betaMet286. We hypothesized that these methionines contribute to etomidate sites formed at alpha-beta subunit interfaces and that increasing side-chain bulk and hydrophobicity at either locus would mimic etomidate binding and block etomidate effects. Channel activity was electrophysiologically quantified in alpha(1)beta(2)gamma(2L) receptors with alpha(1)M236W or beta(2)M286W mutations, in both the absence and the presence of etomidate. Measurements included spontaneous activation, GABA EC(50), etomidate agonist potentiation, etomidate direct activation, and rapid macrocurrent kinetics. Both alpha(1)M236W and beta(2)M286W mutations induced spontaneous channel opening, lowered GABA EC(50), increased maximal GABA efficacy, and slowed current deactivation, mimicking effects of etomidate on alpha(1)beta(2)gamma(2L) channels. These changes were larger with alpha(1)M236W than with beta(2)M286W. Etomidate (3.2 muM) reduced GABA EC(50) much less in alpha(1)M236Wbeta(2)gamma(2L) receptors (2-fold) than in wild type (23-fold). However, etomidate was more potent and efficacious in directly activating alpha(1)M236Wbeta(2)gamma(2L) compared with wild type. In alpha(1)beta(2)M286Wgamma(2L) receptors, etomidate induced neither agonist-potentiation nor direct channel activation. These results support the hypothesis that alpha(1)Met236 and beta(2)Met286 are within etomidate sites that allosterically link to channel gating. Although alpha(1)M236W produced the larger impact on channel gating, beta(2)M286W produced more profound changes in etomidate sensitivity, suggesting a dominant role in drug binding. Furthermore, quantitative mechanistic analysis demonstrated that wild-type and mutant results are consistent with the presence of only one class of etomidate sites mediating both agonist potentiation and direct activation.
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Desai R, Kronengold J, Mei J, Forman SA, Kaczmarek LK. Protein kinase C modulates inactivation of Kv3.3 channels. J Biol Chem 2008; 283:22283-94. [PMID: 18539595 DOI: 10.1074/jbc.m801663200] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Modulation of some Kv3 family potassium channels by protein kinase C (PKC) regulates their amplitude and kinetics and adjusts firing patterns of auditory neurons in response to stimulation. Nevertheless, little is known about the modulation of Kv3.3, a channel that is widely expressed throughout the nervous system and is the dominant Kv3 family member in auditory brainstem. We have cloned the cDNA for the Kv3.3 channel from mouse brain and have expressed it in a mammalian cell line and in Xenopus oocytes to characterize its biophysical properties and modulation by PKC. Kv3.3 currents activate at positive voltages and undergo inactivation with time constants of 150-250 ms. Activators of PKC increased current amplitude and removed inactivation of Kv3.3 currents, and a specific PKC pseudosubstrate inhibitor peptide prevented the effects of the activators. Elimination of the first 78 amino acids of the N terminus of Kv3.3 produced noninactivating currents suggesting that PKC modulates N-type inactivation, potentially by phosphorylation of sites in this region. To identify potential phosphorylation sites, we investigated the response of channels in which serines in this N-terminal domain were subjected to mutagenesis. Our results suggest that serines at positions 3 and 9 are potential PKC phosphorylation sites. Computer simulations of model neurons suggest that phosphorylation of Kv3.3 by PKC may allow neurons to maintain action potential height during stimulation at high frequencies, and may therefore contribute to stimulus-induced changes in the intrinsic excitability of neurons such as those of the auditory brainstem.
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85
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Arunpriya S, Reddy B, Desai R, Manjunath S, Shubhalakshmi S, Umashankar K. Treatment of condylar fractures: therapeutic controversies continue…. Int J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.ijom.2007.08.416] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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86
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Gupta A, Reddy B, Desai R, Ghosla S, Shubhalakshmi S, Umashankar K. Pedicled buccal pad of fat—a trust worthy adjunct in cleft palate repair. Int J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.ijom.2007.08.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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87
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Vinay M, Reddy B, Desai R, Manjunath S, Shubhalakshmi S, Umashankar K. Injection painful? Try with this new technique. Int J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.ijom.2007.08.243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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88
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Dadhich A, Praveen Reddy B, Desai R, Manjunath S, Shubhalakshmi S, Umashankar K. Hyperplasia of temporal fat pad – a rare case report. Int J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.ijom.2007.09.084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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89
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Chavan K, Reddy B, Desai R, Manjunath S, Shubhalakshmi S, Umashankar K. Versatility of pectoralis major myocutaneous flap. Int J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.ijom.2007.08.346] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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90
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Veersangappa C, Reddy B, Desai R, Manjunath S, Shubhalakshmi S, Umashankar K. R U anxious!!!! A study regarding anxiety levels in dental students. Int J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.ijom.2007.08.242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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91
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Rohit S, Praveen Reddy B, Desai R, Manjunath S, Shubhalakshmi S, Umashankar K. Prophylactic antibiotics for mandibular third molar surgery: a supportive or dissenting opinion. Int J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.ijom.2007.08.172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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92
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Bandiwadekar T, Reddy B, Desai R, Manjunath S, Shubhalakshmi S, Umashankar K. Odontogenic tumours-an enigma to surgeon. Int J Oral Maxillofac Surg 2007. [DOI: 10.1016/j.ijom.2007.08.314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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93
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Auluck A, Shetty S, Desai R, Mupparapu M. Recurrent ameloblastoma of the infratemporal fossa: diagnostic implications and a review of the literature. Dentomaxillofac Radiol 2007; 36:416-9. [PMID: 17881602 DOI: 10.1259/dmfr/45988074] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
It is unusual for odontogenic tumours such as ameloblastoma to occur in the infratemporal fossa. Although these odontogenic tumours usually arise in jaws, they can infiltrate into the infratemporal region, pterygomaxillary space or fissure, invading soft tissues by way of extension. A case of recurrent ameloblastoma in the infratemporal fossa region arising from an extension of the lesion from the site of previous occurrence in the right mandibular body is reported.
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94
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Garai K, Sahoo B, Kaushalya SK, Desai R, Maiti S. Zinc Lowers Amyloid-β Toxicity by Selectively Precipitating Aggregation Intermediates. Biochemistry 2007; 46:10655-63. [PMID: 17718543 DOI: 10.1021/bi700798b] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Soluble amyloid-beta (Abeta) aggregates are suspected to play a major role in Alzheimer's disease. Zn2+ at a concentration of a few micromolar, which is too dilute to affect the precipitation equilibrium of Abeta, can destabilize these aggregates [Garai, K., Sengupta, P., Sahoo, B., and Maiti, S. (2006) Biochem. Biophys. Res. Commun. 345, 210-215]. Here we investigate the nature of these aggregates in the context of the precipitation pathway, the mechanism underlying their destabilization, and the biological consequences of this destabilization. We show that the larger soluble aggregates (size >10 nm) form only in supersaturated Abeta solutions, implying that they are intermediates in the pathway toward fibril formation. We also show that Zn2+ destabilizes these intermediates by accelerating their aggregation kinetics. The resulting change in the size distribution of the Abeta solution is sufficient to eliminate its toxicity to cultured mammalian neurons. Our results provide an explanation for the existing observations that Zn2+ at a concentration of a few micromolar significantly reduces Abeta toxicity.
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95
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Yang B, Desai R, Kaczmarek LK. Slack and Slick K(Na) channels regulate the accuracy of timing of auditory neurons. J Neurosci 2007; 27:2617-27. [PMID: 17344399 PMCID: PMC6672517 DOI: 10.1523/jneurosci.5308-06.2007] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The Slack (sequence like a calcium-activated K channel) and Slick (sequence like an intermediate conductance K channel) genes, which encode sodium-activated K+ (K(Na)) channels, are expressed at high levels in neurons of the medial nucleus of the trapezoid body (MNTB) in the auditory brainstem. These neurons lock their action potentials to incoming stimuli with a high degree of temporal precision. Channels with unitary properties similar to those of Slack and/or Slick channels, which are gated by [Na+]i and [Cl-]i and by changes in cytoplasmic ATP levels, are present in MNTB neurons. Manipulations of the level of K(Na) current in MNTB neurons, either by increasing levels of internal Na+ or by exposure to a pharmacological activator of Slack channels, significantly enhance the accuracy of timing of action potentials at high frequencies of stimulation. These findings suggest that such fidelity of timing at high frequencies may be attributed in part to high-conductance K(Na) channels.
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96
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Carl DE, Desai R. An unusual case of obstructive uropathy. Kidney Int 2007; 71:186. [PMID: 17252025 DOI: 10.1038/sj.ki.5001876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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97
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Flavell RA, Kaczmarek LK, Badou A, Boulpaep EL, Desai R, Basavappa S, Matza D, Peng YQ, Mehal WZ. Retraction. Science 2006; 310:1903. [PMID: 16373558 DOI: 10.1126/science.310.5756.1903b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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98
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Balaji J, Desai R, Kaushalya SK, Eaton MJ, Maiti S. Quantitative measurement of serotonin synthesis and sequestration in individual live neuronal cells. J Neurochem 2005; 95:1217-26. [PMID: 16269014 DOI: 10.1111/j.1471-4159.2005.03489.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Synthesis and subsequent sequestration into vesicles are essential steps that precede neurotransmitter exocytosis, but neither the total neurotransmitter content nor the fraction sequestered into vesicles have been measured in individual live neurons. We use multiphoton microscopy to directly observe intracellular and intravesicular serotonin in the serotonergic neuronal cell line RN46A. We focus on how the relationship between synthesis and sequestration changes as synthesis is up-regulated by differentiation or down-regulated by chemical inhibition. Temperature-induced differentiation causes an increase of about 60% in the total serotonin content of individual cells, which goes up to about 10 fmol. However, the number of vesicles per cell increases by a factor of four and the proportion of serotonin sequestered inside the vesicles increases by a factor of five. When serotonin synthesis is inhibited in differentiated cells and the serotonin content goes down to the level present in undifferentiated cells, the sequestered proportion still remains at this high level. The total neurotransmitter content of a cell is, thus, an unreliable indicator of the sequestered amount.
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99
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Binder JR, Medler DA, Desai R, Conant LL, Liebenthal E. Some neurophysiological constraints on models of word naming. Neuroimage 2005; 27:677-93. [PMID: 15921937 DOI: 10.1016/j.neuroimage.2005.04.029] [Citation(s) in RCA: 166] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2004] [Revised: 03/24/2005] [Accepted: 04/15/2005] [Indexed: 11/30/2022] Open
Abstract
The pronunciation of irregular words in deep orthographies like English cannot be specified by simple rules. On the other hand, the fact that novel letter strings can be pronounced seems to imply the existence of such rules. These facts motivate dual-route models of word naming, which postulate separate lexical (whole-word) and non-lexical (rule-based) mechanisms for accessing phonology. We used fMRI during oral naming of irregular words, regular words, and nonwords, to test this theory against a competing single-mechanism account known as the triangle model, which proposes that all words are handled by a single system containing distributed orthographic, phonological, and semantic codes rather than word codes. Two versions of the dual-route model were distinguished: an 'exclusive' version in which activation of one processing route predominates over the other, and a 'parallel' version in which both routes are equally activated by all words. The fMRI results provide no support for the exclusive dual-route model. Several frontal, insular, anterior cingulate, and parietal regions showed responses that increased with naming difficulty (nonword > irregular word > regular word) and were correlated with response time, but there was no activation consistent with the predicted response of a non-lexical, rule-based mechanism (i.e., nonword > regular word > irregular word). Several regions, including the angular gyrus and dorsal prefrontal cortex bilaterally, left ventromedial temporal lobe, and posterior cingulate gyrus, were activated more by words than nonwords, but these 'lexical route' regions were equally active for irregular and regular words. The results are compatible with both the parallel dual-route model and the triangle model. 'Lexical route' regions also showed effects of word imageability. Together with previous imaging studies using semantic task contrasts, the imageability effects are consistent with semantic processing in these brain regions, suggesting that word naming is partly semantically-mediated.
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100
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Kaczmarek LK, Bhattacharjee A, Desai R, Gan L, Song P, von Hehn CAA, Whim MD, Yang B. Regulation of the timing of MNTB neurons by short-term and long-term modulation of potassium channels. Hear Res 2005; 206:133-45. [PMID: 16081004 DOI: 10.1016/j.heares.2004.11.023] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2004] [Accepted: 11/16/2004] [Indexed: 11/23/2022]
Abstract
The firing patterns of neurons in central auditory pathways encode specific features of sound stimuli, such as frequency, intensity and localization in space. The generation of the appropriate pattern depends, to a major extent, on the properties of the voltage-dependent potassium channels in these neurons. The mammalian auditory pathways that compute the direction of a sound source are located in the brainstem and include the connection from bushy cells in the anteroventral cochlear nucleus (AVCN) to the principal neurons of the medial nucleus of the trapezoid body (MNTB). To preserve the fidelity of timing of action potentials that is required for sound localization, these neurons express several types of potassium channels, including the Kv3 and Kv1 families of voltage-dependent channels and the Slick and Slack sodium-dependent channels. These channels determine the pattern of action potentials and the amount of neurotransmitter released during repeated stimulation. The amplitude of currents carried by one of these channels, the Kv3.1b channel, is regulated in the short term by protein phosphorylation, and in the long term, by changes in gene expression, such that the intrinsic excitability of the neurons is constantly being regulated by the ambient auditory environment.
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