Publications by authors named "Bitner R"

Osteoarthritis (OA) is a degenerative form of arthritis that can result in loss of joint function and chronic pain. The pathological pain state that develops with OA disease involves plastic changes in the peripheral and central nervous systems, however, the cellular mechanisms underlying OA are not fully understood. We characterized the medial meniscal tear (MMT) surgical model and the intra-articular injection of monosodium iodoacetate (MIA) chemical model of OA in rats.

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Unlabelled: Voltage-gated Ca(2+) channels play an important role in nociceptive transmission. There is significant evidence supporting a role for N-, T- and P/Q-type Ca(2+) channels in chronic pain. Here, we report that A-1264087, a structurally novel state-dependent blocker, inhibits each of these human Ca(2+) channels with similar potency (IC50 = 1-2 μM).

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Injury to the peripheral or central nervous system can induce changes within the nervous tissues that promote a state of sensitization that may underlie conditions of pathological chronic pain. A key biochemical event in the initiation and maintenance of peripheral and central neuronal sensitization associated with chronic pain is the phosphorylation and subsequent activation of mitogen-activated protein kinases (MAPKs) and immediate early gene transcription factors, in particular cAMP-response element binding protein (CREB). In this commentary we review the preclinical data that describe anatomical and mechanistic aspects of nociceptive-induced signaling along nociceptive pathways including peripheral cutaneous axons, the dorsal root ganglia, spinal cord dorsal horn and cerebral cortex.

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Alzheimer disease (AD) is a progressive neurodegenerative disorder with associated memory loss, spatial disorientation, and other psychiatric problems. Cholinergic system dysfunction is an early and salient feature of AD, and enhancing cholinergic signaling with acetylcholinesterase inhibitors is currently the primary strategy for improving cognition. The beneficial effects of acetylcholinesterase inhibitors, however, are typically short-lived and accompanied by adverse effects.

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Background: Microglia serve as macrophage-like cells in the central nervous system, and activation of microglial cells in the spinal cord may contribute to ongoing pain following peripheral trauma or nerve injury. Following pronociceptive stimulation, activated microglia exhibit increased expression of the peripheral benzodiazepine receptor (PBR)/translocator protein 18 kDa (TSPO).

Methods: Using radioligand binding autoradiography and filtration assays, we examined the specific binding of the PBR/TSPO ligand [(3)H]PK11195 in spinal cords from the following rat experimental pain models: neuropathic pain induced by spinal nerve ligation (SNL), osteoarthritic pain induced by intraarticular injection of monosodium iodoacetate in the knee joint (MIA-OA), and subchronic inflammatory pain induced by intraplantar injection of complete Freund's adjuvant (CFA).

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Nicotinic acetylcholine receptor (nAChR) agonists improve sensory gating deficits in animal models and schizophrenic patients. The aim of this study was to determine whether the novel and selective α7 nAChR full agonist 5-(6-[(3R)-1-azabicyclo[2.2.

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Blockade of the histamine H(3) receptor (H(3)R) enhances central neurotransmitter release, making it an attractive target for the treatment of cognitive disorders. Here, we present in vitro and in vivo pharmacological profiles for the H(3)R antagonist 2-[4'-((3aR,6aR)-5-methyl-hexahydro-pyrrolo[3,4-b]pyrrol-1-yl)-biphenyl-4-yl]-2H-pyridazin-3-one (ABT-288). ABT-288 is a competitive antagonist with high affinity and selectivity for human and rat H(3)Rs (K(i) = 1.

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Calcium-mediated pathologic activation of the cysteine protease calpain has been linked to neurodegenerative disorders such as Alzheimer's disease (AD) through the cleavage of proteolytic substrates that negatively affect neuronal function. Hyperphosphorylation of the microtubule-associated protein tau and the subsequent aggregation of tau filaments resulting in the intracellular formation of neurofibrillary tangles are recognized as key etiological factors in AD pathology. Cyclin-dependent kinase 5 (Cdk5), a major kinase responsible for tau hyperphosphorylation in the AD brain, becomes hyperactivated through calpain-mediated cleavage-conversion of the Cdk5 regulatory protein p35 to p25.

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Rationale: Antipsychotics normalize responses in the DBA/2 mouse model of prepulse inhibition (PPI), a preclinical model of sensorimotor gating deficits. The α7 nicotinic acetylcholine receptor (nAChR) as a molecular target is considered an attractive approach for improvement of cognitive deficits in schizophrenia (CDS). Assessment of clinical efficacy of novel agents in CDS involves treating patients already on antipsychotic medications.

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Background: Intra-articular injection of monosodium iodoacetate (MIA) in the knee joint of rats disrupts chondrocyte metabolism resulting in cartilage degeneration and subsequent nociceptive behavior that has been described as a model of osteoarthritis (OA) pain. Central sensitization through activation of mitogen activated protein kinases (MAPKs) is recognized as a pathogenic mechanism in chronic pain. In the present studies, induction of central sensitization as indicated by spinal dorsal horn MAPK activation, specifically ERK and p38 phosphorylation, was assessed in the MIA-OA model.

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Background: Psychiatric training was once synonymous with learning psychotherapy, but current psychiatric trainees face many options for integrating psychopharmacology and psychotherapy into their future practices, including providing primarily medication-focused visits. We examined psychiatry residents' attitudes towards learning psychotherapy, practicing psychotherapy in the future, and overall identification as psychotherapists.

Methods: We surveyed residents from 15 US residency programs during 2006-2007.

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This paper outlines and discusses two models of training for group Mindfulness-Based Cognitive Therapy (MBCT) which we have called and . MBCT training and practice focuses on present moment experience versus content, focused on gaining a metacognitive perspective on one's thoughts and internal processes. Trainees and trainers share their reflections on the training process as well as the experiential and acceptance-based framework of MBCT reflected in the training process itself.

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Histamine H(3) receptor antagonists enhance cognition in preclinical models and have been proposed as novel therapeutics for cognitive disorders, in particular Alzheimer's disease (AD). Increased neurotransmitter (e.g.

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We previously reported that alpha7 nicotinic acetylcholine receptor (nAChR) agonism produces efficacy in preclinical cognition models correlating with activation of cognitive and neuroprotective signaling pathways associated with Alzheimer's disease (AD) pathology. In the present studies, the selective and potent alpha7 nAChR agonist 5-(6-[(3R)-1-azabicyclo[2.2.

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Objective: Few studies of residents' attitudes toward psychotherapy training exist. The authors examined residents' perceptions of the quality of their training, support for training, their own competence levels, and associations between self-perceived competence and perceptions of the training environment.

Methods: An anonymous, web-based questionnaire was distributed to residents at 15 U.

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Mutant Tg2576 mice which possess the human "Swedish" APP mutation have been shown to demonstrate both Abeta plaque pathology and memory deficits in behavioral tasks. These mice are routinely maintained on a mixed C57BL/6xSJL genetic background which exhibits a high frequency of retinal degeneration allele and high variability in many behavioral assays. The same APP mutation is also available maintained on a 129 genetic background, providing more genetic homogeneity, but little data are published regarding the effects of the mutation on this background.

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The alpha7 nicotinic acetylcholine receptor (nAChR) plays an important role in cognitive processes and has generated recent interest as a potential drug target for treating neurodegenerative disorders such as Alzheimer's disease (AD). The property of Ca(2+) permeation associated with alpha7 nAChR agonism may lead to Ca(2+)-dependent intracellular signaling that contribute to the procognitive and neuroprotective effects that have been described with this pharmacology. In this study, we investigated whether alpha7 nAChR agonism leads to increased phosphorylation of the inhibitory regulating amino acid residue Ser-9 on GSK3beta, a major kinase responsible for tau hyperphosphorylation in AD neuropathology.

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Existing data on the expression of H(4) histamine receptor in the CNS are conflicting and inconclusive. In this report, we present the results of experiments that were conducted in order to elucidate H(4) receptor expression and localization in the brain, spinal cord, and dorsal root ganglia (DRG). Here we show that transcripts of H(4) receptor are present in all analyzed regions of the human CNS, including spinal cord, hippocampus, cortex, thalamus and amygdala, with the highest levels of H(4) mRNA detected in the spinal cord.

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We have previously shown that beta-amyloid (Abeta) oligomers induced dynamin 1 and tau cleavage in cultured hippocampal neurons. As a result of this cleavage, dynamin 1 levels decreased and a toxic tau fragment was generated. Abeta-induced cleavage of these proteins was calpain-mediated and impacted both synaptic vesicle recycling and the integrity of neuronal processes [Kelly, B.

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Among the diverse sets of nicotinic acetylcholine receptors (nAChRs), the alpha7 subtype is highly expressed in the hippocampus and cortex and is thought to play important roles in a variety of cognitive processes. In this review, we describe the properties of a novel biaryl diamine alpha7 nAChR agonist, A-582941. A-582941 was found to exhibit high-affinity binding and partial agonism at alpha7 nAChRs, with acceptable pharmacokinetic properties and excellent distribution to the central nervous system (CNS).

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The histamine H3 receptor, first described in 1983 as a histamine autoreceptor and later shown to also function as a heteroreceptor that regulates the release of other neurotransmitters, has been the focus of research by numerous laboratories as it represents an attractive drug target for a number of indications including cognition. The purpose of this review is to acquaint the reader with the current understanding of H3 receptor localization and function as a modulator of neurotransmitter release and its effects on cognitive processes, as well as to provide an update on selected H3 antagonists in various states of preclinical and clinical advancement. Blockade of centrally localized H3 receptors by selective H3 receptor antagonists has been shown to enhance the release of neurotransmitters such as histamine, ACh, dopamine and norepinephrine, among others, which play important roles in cognitive processes.

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The nicotinic acetylcholine receptors (nAChRs) play critical roles in neuronal transmission and modulation. Among the diverse nAChRs, the alpha7 subtype has been considered as a potential therapeutic target for treating cognitive deficits associated with neuropsychiatric and neurodegenerative diseases. Although a number of mechanisms including neurotransmitter and biochemical effects linking alpha7 nAChR activation and cognitive function are beginning to be described, the underlying molecular processes especially following repeated administration remain unclear.

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The alpha7 nicotinic acetylcholine receptor (nAChR) plays an important role in cognitive processes and may represent a drug target for treating cognitive deficits in neurodegenerative and psychiatric disorders. In the present study, we used a novel alpha7 nAChR-selective agonist, 2-methyl-5-(6-phenyl-pyridazin-3-yl)-octahydro-pyrrolo[3,4-c]pyrrole (A-582941) to interrogate cognitive efficacy, as well as examine potential cellular mechanisms of cognition. Exhibiting high affinity to native rat (Ki = 10.

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