Publications by authors named "Akopian G"

Background: Current guidelines for management of anorectal abscesses make no recommendations for operative vs bedside incision and drainage (I&D). The purpose of this study was to determine if management in the operating room is necessary to adequately drain anorectal abscesses and prevent short-term complications for patients presenting to the emergency department (ED).

Methods: Patients with perirectal abscesses were identified and divided into two groups based on intervention type: "bedside" or "operative.

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We sought to examine the intrarenal fluid and tissue temperature alterations during dusting and fragmentation with the thulium fiber laser (TFL) in an porcine kidney. In two female Yorkshire pigs, temperature was continuously measured within the upper, interpolar, and lower calices along with the renal pelvis using multipoint thermal sensor probes; another temperature probe was situated at the tip of the ureteroscope. Four experimental protocols were performed for each animal: dual lumen ureteroscope with both warmed (37°C) irrigation and room temperature (20°C-22°C) irrigation and single lumen ureteroscope with warmed and room temperature irrigation.

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Level structures in the neutron-rich ^{144}Ba nucleus have been reinvestigated by measuring prompt γ rays in the spontaneous fission of ^{252}Cf. The previous s=+1 octupole band structure with reflection asymmetric shape has been expanded, and a side quadrupole band structure based on a 3^{+} state with reflection symmetric shape is identified. Thus, the results show the coexistence of reflection asymmetric and symmetric shapes in ^{144}Ba.

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The ^{7}H system was populated in the ^{2}H(^{8}He,^{3}He)^{7}H reaction with a 26 AMeV ^{8}He beam. The ^{7}H missing mass energy spectrum, the ^{3}H energy and angular distributions in the ^{7}H decay frame were reconstructed. The ^{7}H missing mass spectrum shows a peak, which can be interpreted either as unresolved 5/2^{+} and 3/2^{+} doublet or one of these states at 6.

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Mike Levine's body of work guides thinking on how the basal ganglia process information to create coordinated movements and skill learning throughout the life span and in disease. This special issue is a nod to Mike's career and a well-deserved gesture by the neuroscience community thanking him for the impact he has made on many people's careers and the field of basal ganglia physiology. This paper reviews how aging impacts basal ganglia processing with a focus on single cell and synaptic physiology.

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The present study examined synaptic communication between direct and indirect output pathway striatal medium-sized spiny neurons (MSNs) and their target structures, the substantia nigra pars reticulata (SNr) and the external globus pallidus (GPe) in two mouse models of Huntington's disease (HD). Cre recombination, optogenetics, and whole-cell patch-clamp recordings were used to determine alterations in intrinsic and synaptic properties of SNr and GPe neurons from both male and female symptomatic R6/2 (>60 d) and presymptomatic (2 months) or symptomatic (10-12 months) YAC128 mice. Cell membrane capacitance was decreased, whereas input resistance was increased in SNr neurons from R6/2, but not YAC128 mice.

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In mouse models of Huntington's disease (HD), striatal neuron properties are significantly altered. These alterations predict changes in striatal output regions. However, little is known about alterations in those regions.

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Previous work from our laboratories has shown that juvenile Fischer 344 (F344) rats are less playful than other strains and also appear to be compromised in dopamine (DA) functioning. To determine whether the dysfunctional play in this strain is associated with deficits in the handling and delivery of vesicular DA, the following experiments assessed the extent to which F344 rats are differentially sensitive to the effects of amphetamine. When exposed to amphetamine, striatal slices obtained from F344 rats showed a small increase in unstimulated DA release when compared with slices from Sprague-Dawley rats; they also showed a more rapid high K+-mediated release of DA.

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Background: Carotid endarterectomy (CEA) as treatment in patients with asymptomatic carotid stenosis is the subject of much debate.

Methods: The National Surgical Quality Improvement Program database from 2005 to 2012 was queried. Patients undergoing CEA for asymptomatic carotid stenosis were identified.

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Exercise has been shown to be beneficial for Parkinson's disease (PD). A major interest in our lab has been to investigate how exercise modulates basal ganglia function and modifies disease progression. Dopamine (DA) depletion leads to loss of dendritic spines within the caudate nucleus and putamen (striatum) in PD and its animal models and contributes to motor impairments.

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Airborne particulate matter (PM) from urban vehicular aerosols altered glutamate receptor functions and induced glial inflammatory responses in rodent models after chronic exposure. Potential neurotoxic mechanisms were analyzed in vitro. In hippocampal slices, 2 h exposure to aqueous nanosized PM (nPM) selectively altered post-synaptic proteins in cornu ammonis area 1 (CA1) neurons: increased GluA1, GluN2A, and GluN2B, but not GluA2, GluN1, or mGlur5; increased post synaptic density 95 and spinophilin, but not synaptophysin, while dentate gyrus (DG) neurons were unresponsive.

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The α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic-acid-type glutamate receptor (AMPAR) plays a critical role in modulating experience-dependent neuroplasticity, and alterations in AMPAR expression may underlie synaptic dysfunction and disease pathophysiology. Using the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of dopamine (DA) depletion, our previous work showed exercise increases total GluA2 subunit expression and the contribution of GluA2-containing channels in MPTP mice. The purpose of this study was to determine whether exercise-dependent changes in AMPAR expression after MPTP are specific to the striatopallidal (D2 R) or striatonigral (D1 R) medium spiny neuron (MSN) striatal projection pathways.

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Alzheimer's disease is a progressive neurodegenerative disease that entails impairments of memory, thinking and behavior and culminates into brain atrophy. Impaired glucose uptake (accumulating into energy deficits) and synaptic plasticity have been shown to be affected in the early stages of Alzheimer's disease. This study examines the ability of lipoic acid to increase brain glucose uptake and lead to improvements in synaptic plasticity on a triple transgenic mouse model of Alzheimer's disease (3xTg-AD) that shows progression of pathology as a function of age; two age groups: 6 months (young) and 12 months (old) were used in this study.

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Quality measures for prognostication of colon cancer include the removal of 12 or more lymph nodes during colon resection. The purpose of this study was to determine whether emergent surgery is associated with inadequate lymph node harvest. The National Cancer Database (NCDB) was queried for colon cancer patients operated on at Huntington Memorial Hospital, Pasadena, California, from 2005 to 2010.

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The 0+ ground state of the 10He nucleus produced in the 3H(8He,p)10He reaction was found at about 2.1±0.2  MeV (Γ∼2  MeV) above the three-body ^{8}He+n+n breakup threshold.

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In the central nervous system, two calpain isoforms are highly expressed: calpain1 and calpain2. Here, we show for the first time that activation of the calpain isoform, calpain2, is a necessary event in hippocampal synaptic plasticity and in learning and memory. We developed a fluorescence resonance energy transfer-based animal model to monitor in vivo calpain activation in single cells and in real time.

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The striatum is particularly vulnerable to mitochondrial dysfunction and this problem is linked to pathology created by environmental neurotoxins, stimulants like amphetamine, and metabolic disease and ischemia. We studied the course of recovery following a single systemic injection of the mitochondrial complex II inhibitor 3-nitropropionic acid (3-NP) and found 3-NP caused lasting changes in motor behavior that were associated with altered activity-dependent plasticity at corticostriatal synapses in Fischer 344 rats. The changes in synapse behavior varied with the time after exposure to the 3-NP injection.

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The purpose of this study was to use the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database to evaluate the incidence of postoperative surgical site infections (SSIs) between laparoscopic (LAP) and open colorectal surgery. The 2008 ACS-NSQIP Participant Use File was queried by Current Procedural Terminology codes for colorectal surgery cases. SSI rates were compared between groups using Pearson chi-square and Fisher exact tests.

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Regularities of biologically active lipid metabolites formation in dynamics (5, 10, 30, 60 s) by phorbol 12-miristate 13-acetate stimulation in [14C]palmitic acid have been investigated in normal and leukemia peripheral blood lymphocytes prelabeled with [14C]palmitate. In normal cells there was two-phase formation of 1,2-diacylglycerol (5, 30 s), lysophosphatidylcholine (10, 60 s), as well as free palmitic acid at 10 s of stimulation. Under the identical experimental conditions there was inhibition of investigated lipid release processes at early (5 and 10 s) stages of stimulation of leukemic lymphocytes.

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Background: The small intestinal bacterial overgrowth (SIBO) breath test has had positive results in 84% of patients with irritable bowel syndrome vs 20% of controls. We hypothesized that SIBO would be more prevalent in patients with symptoms consistent with irritable bowel syndrome who have undergone previous abdominal surgery.

Objective: To identify causative factors for SIBO.

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Epidemiological and clinical studies have suggested that exercise is beneficial for patients with Parkinson's disease (PD). Through research in normal (noninjured) animals, neuroscientists have begun to understand the mechanisms in the brain by which behavioral training and exercise facilitates improvement in motor behavior through modulation of neuronal function and structure, called experience-dependent neuroplasticity. Recent studies are beginning to reveal molecules and downstream signaling pathways that are regulated during exercise and motor learning in animal models of PD and that are important in driving protective and/or adaptive changes in neuronal connections of the basal ganglia and related circuitry.

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Juvenile Fischer 344 rats are known to be less playful than other inbred strains, although the neurobiological substrate(s) responsible for this phenotype is uncertain. In the present study, Fischer 344 rats were compared to the commonly used outbred Sprague-Dawley strain on several behavioral and physiological parameters in order to ascertain whether the lack of play may be related to compromised activity of brain dopamine (DA) systems. As expected, Fischer 344 rats were far less playful than Sprague-Dawley rats, with Fischer 344 rats less likely to initiate playful contacts with a playful partner and less likely to respond playfully to these contacts.

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Objective: While the influence of initial TransAtlantic InterSociety Consensus (TASC) II classification has been clearly shown to influence the primary patency of infrainguinal stenting procedures, its effect on outcomes once stent failure has occurred is less well documented. It is the objective of this paper to determine whether clinical outcomes and implications of anatomic stent failure vary according to initial TASC II classification.

Methods: Results were analyzed by TASC II classification.

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Enteral insufficiency is considered to trigger the syndrome of endogenous intoxication and, further, multiple organ failure. Enteral insufficiency often accompanies postoperative septic complications, such as peritonitis. Morphologic changes of the intestinal wall by septic peritonitis consisted of edema, fibrinous degradation of muscular layer and dystrophy of local nervous pathways.

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