A Novel Hybrid-Structured Titanium Surface Promotes Adhesion of Human Dermal Fibroblasts and Osteogenesis of Human Mesenchymal Stem Cells while Reducing S-epidermidis Biofilm Accumulation
differentiation; energy; hydrophilicity; implants; in-vitro; Materials Science; nanotopography; osseointegration; osteoactivin; osteoblast lineage cells; responses
We provide a comparative analysis of protein adsorption, primary human cell behavior, and biofilm formation on modified titanium substrates of either micro-, nano-, or hybrid micro/nano-scale feature sizes. While studies revealed that nano-scale structures initially decreased the attachment and spreading of both human fibroblasts (hDFs) and mesenchymal stem cells (hMSCs), hMSC differentiation studies revealed that hybrid structures promoted the highest levels of osteogenic gene expression and attenuated biofilm formation by Staphylococcus epidermidis. Taken together, this novel approach of generating a hybrid topographical feature results in a potential implant material capable of enhanced dermal cell adhesion and osteogenic differentiation while limiting biofilm accumulation.
Park B W; Krieger J; Sondag G R; Moussa F M; Rankenberg J; Safadi F F; Gatsonis N A; McGimpsey W G; Lambert C R; Malcuit C
Advanced Engineering Materials
2016
2016-04
Journal Article
<a href="http://doi.org/10.1002/adem.201500282" target="_blank" rel="noreferrer noopener">10.1002/adem.201500282</a>
Frequency sensitivity range of the saccule to bone-conducted stimuli measured by vestibular evoked myogenic potentials
Audiology & Speech-Language Pathology; bone conduction; frequency sensitivity range; myogenic potential; nerve; neurons; Neurosciences & Neurology; Otorhinolaryngology; repetition rate; responses; saccule; sound; squirrel-monkey; vestibular; vestibular evoked myogenic potential; vibration
Vestibular evoked myogenic potentials (VEMPs) occurring in cervical muscles after intense sound stimulation conducted by air or bone are thought to be a polysynaptic response of otolith-vestibular nerve origin. We report the results of an experiment to investigate whether acoustic stimulation of the saccule by bone conduction produces VEMPs in which response amplitudes are somewhat sensitive to stimulus frequency, as appears, to be the case with air-conducted stimuli. Prior to this we investigated the effect of stimulation repetition rate on bone-conducted VEMPs (B-VEMPs) at stimulus frequencies of 200 and 400 Hz with five different repetition rates (5, 10, 20, 40, and 80 Hz). B-VEMPs were recorded from 12 normal hearing subjects in response to bone-conducted 70 dB (normal hearing level), 10-ms tone bursts (rise/fall time = 1 ms and plateau time = 8 ms) at frequencies of 100, 200, 400, 800, 1600 and 3200 Hz. Our study showed that B-VEMP amplitudes were highest at 10 Hz but decreased as the repetition rate increased. B-VEMP response amplitudes were found to be maximal for stimulus frequencies from 200 to 400 Hz. This response may contribute to the perception of loud sounds. (C) 2001 Elsevier Science B.V. All rights reserved.
Sheykholeslami K; Kermany M H; Kaga K
Hearing Research
2001
2001-10
Journal Article
<a href="http://doi.org/10.1016/s0378-5955(01)00333-1" target="_blank" rel="noreferrer noopener">10.1016/s0378-5955(01)00333-1</a>
Effect of Artificial Scotomas on Open-Loop Disparity Vergence Eye Movements
binocular disparity; convergence; depth-perception; disparity; dynamic asymmetries; eye movements; fusional; neurons; nystagmus; ocular motor control; Ophthalmology; responses; saccades; single-unit activity; V1; vergence; version
Purpose. To investigate the effect of an artificial scotoma on open-loop disparity vergence responses (DVRs) and vergence control mechanisms, we examined open-loop DVRs to disparity stimuli using monocular artificial scotomas in normal subjects. Methods. Using a mirror haploscope with two computer monitors, we delivered disparity stimuli on a pair of random dot patterns subtending 40 by 30 degrees at 47 cm from each eye. The scotomas were black circles located in the center of a random dot pattern for the left eye. Eye movements of both eyes were recorded with a magnetic search coil system. Results. We first found that the amplitudes of DVRs were gradually decreased and the latency of DVRs was moderately increased as the size of the scotomas was increased. Second, monocular responses from each eye were symmetrical although the stimuli to each eye were asymmetrical. Conclusions. The results suggest that the monocular eye movements in disparity vergence are controlled by a binocular central mechanism, not driven separately by monocular inputs in the open-loop window.
Yang D S; Hertle R W; Zhu M X; Tai Z; Hald E; Kauffman M
Optometry and Vision Science
2015
2015-01
Journal Article
<a href="http://doi.org/10.1097/opx.0000000000000441" target="_blank" rel="noreferrer noopener">10.1097/opx.0000000000000441</a>
AGE-DEPENDENT CHANGES IN OLFACTORY-MEDIATED BEHAVIORAL INVESTIGATIONS IN THE MALE-RAT
Psychology; responses; Neurosciences & Neurology; parkinsons-disease; Behavioral Sciences; recognition; alzheimers-disease; identification; norepinephrine; deficits; bulb; mitral cells; sex odors
Menciowszalek T; Ramirez V D; Dluzen D E
Behavioral and Neural Biology
1992
1992-05
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1016/0163-1047(92)90164-y" target="_blank" rel="noreferrer noopener">10.1016/0163-1047(92)90164-y</a>
Cross-talk Between Nmda And Gaba(a) Receptors In Cultured Neurons Of The Rat Inferior Colliculus
acid type A receptor; calcium influx; cross-talk; currents; dependent protein-kinase; dorsal-horn neurons; gamma-aminobutyric; gamma-aminobutyric-acid; glycine receptors; granule cells; inferior colliculus; intracellular ca2+; Life Sciences & Biomedicine - Other Topics; N-methyl-D-aspartate receptor; pyramidal cells; responses; whole-cell patch-clamp
Cong D N; Tang Z Q; Li L Z; Huang Y N; Wang J; Chen L
Science China-Life Sciences
2011
2011-06
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1007/s11427-011-4178-6" target="_blank" rel="noreferrer noopener">10.1007/s11427-011-4178-6</a>
Oxytocin, Norepinephrine And Olfactory Bulb Mediated Recognition
acetylcholine; acid; male-rats; maternal experience; memory; release; responses; sheep; social recognition; vasopressin
Dluzen D E; Shang Y; Landgraf R
2001
2001
Book/Monograph
n/a
Cataract Surgery And The Primary Care Practitioner
adults; age-related cataract; astigmatism; cortical; Geriatrics & Gerontology; impact; Intraocular lens implantation; men; nuclear sclerosis; posterior subcapsular; presbyopla; responses; risk; smoking; trial
Goldman H B; Kiffel S; Weinstock F J
Geriatrics
2009
2009-05
Journal Article or Conference Abstract Publication
n/a
Behavioral Risk Factors In Emergency Department Patients: A Multisite Survey
cage questionnaire; Emergency Medicine; Emergency Medicine; injury prevention; responses; risk factor surveillance; screening
Lowenstein S R; Koziol-McLain J; Thompson M; Bernstein E; Greenberg K; Gerson L W; Buczynsky P; Blanda M
Academic Emergency Medicine
1998
1998-08
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1111/j.1553-2712.1998.tb02504.x" target="_blank" rel="noreferrer noopener">10.1111/j.1553-2712.1998.tb02504.x</a>
Cartilage Viability After Repetitive Loading: A Preliminary Report
apoptosis; articular-cartilage; cartilage; cell death; chondrocyte; chondrocyte biosynthetic; dynamic compression; experimentally-induced osteoarthritis; explants; guinea-pigs; ii collagen; impact; load; local tissue strain; Orthopedics; repetitive load; responses; Rheumatology; signal-transduction
Lucchinetti E; Adams C S; Horton W E; Torzilli P A
Osteoarthritis and Cartilage
2002
2002-01
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1053/joca.2001.0483" target="_blank" rel="noreferrer noopener">10.1053/joca.2001.0483</a>
Neoadjuvant Chemotherapy In Operable Breast Cancer: The Pros
20-year; chemoendocrine therapy; comparing total; follow-up; gene-expression profiles; mastectomy; Obstetrics & Gynecology; Oncology; pathological; preoperative chemotherapy; project protocol b-27; randomized-trial; responses; sentinel lymph-node; surgical adjuvant breast
Mamounas E R
Breast Care
2006
2006-12
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1159/000097887" target="_blank" rel="noreferrer noopener">10.1159/000097887</a>
Activation Of Nmda Receptors In Hippocampal Area Ca1 By Low And High-frequency Orthodromic Stimulation And Their Contribution To Induction Of Long-term Potentiation
2-amino-5-phosphonovaleric acid; amino-acid receptors; cells; clamp; dentate gyrus; hippocampus; invitro rat hippocampus; kitten visual-cortex; n-methyl-d-aspartate receptor; Neurosciences & Neurology; pyramidal; responses; single-electrode voltage; slices; spinal-cord neurons; stimulation; synaptic plasticity; synaptic transmission; tetanic; time course
N-methyl-D-aspartate (NMDA) receptors are important in many instances of synaptic plasticity. In hippocampal area CA1, long-term potentiation (LTP) can be induced by both NMDA receptor-dependent and -independent mechanisms. Using intracellular recordings and single-electrode voltage clamp, we isolated and characterized NMDA receptor-mediated synaptic responses. NMDA receptor-mediated responses evoked by low frequency orthodromic stimulation were inhibited in a dose-dependent manner by the competitive antagonist D,L-2-amino-5-phosphonovaleric acid (APV). High frequency (tetanic) stimulation, which facilitates synaptic release of glutamate, failed to overcome the blockade of NMDA receptors by APV. Using extracellular recordings of field potentials, we studied the contribution of NMDA receptors to LTP induced by different patterns of tetanic stimulation. LTP was inhibited in a dose-dependent manner by APV, but was more sensitive to APV than were NMDA receptor-mediated synaptic responses. This most likely reflects a threshold for NMDA receptor activation in LTP induction. A component of LTP that resisted blockade by APV was induced by high (200 Hz), but not low (25 Hz), frequency tetanization. This NMDA receptor-independent component of LTP persisted for > 4 hours and accounted for approximately half the potentiation induced by 200 Hz tetanization. Procedures necessary to induce LTP at the Schaffer collateral/commissural synapses in area CA1 by both NMDA receptor-dependent and -independent mechanisms are now well characterized. Using the same neuronal population, it will be possible to ask if processes involved in the maintenance of LTP are shared even when LTP is induced through two different mechanisms. (C) 1994 Wiley-Liss, Inc.
Grover L M; Teyler T J
Synapse
1994
1994-01
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1002/syn.890160108" target="_blank" rel="noreferrer noopener">10.1002/syn.890160108</a>
Affinity Manipulation Of Surface-conjugated Rgd Peptide To Modulate Binding Of Liposomes To Activated Platelets
cyclic RGD; delivery systems; drug-eluting stents; Engineering; insight; integrin alpha(iib)beta(3); liposomes; Materials Science; nanoparticles; peptide modification; platelet-targeting; responses; restenosis; therapy
Platelet adhesion, activation and fibrinogen-mediated aggregation are primary events in vascular thrombosis and occlusion. An injectable delivery system that can carry thrombolytics selectively to the sites of active platelet aggregation has immense potential in minimally invasive targeted therapy of vascular occlusion. To this end we are studying liposomes surface-modified by fibrinogen-mimetic RGD motifs that can selectively target and bind integrin GPIIb-IIIa on activated platelets. Here we report liposome surface-modification with a conformationally constrained high affinity cyclic RGD motif to modulate the GPIIb-IIIa-binding capability of the liposomes. Such affinity enhancement is important for practical in vivo applications to compete with native fibrinogen towards binding GPIIb-IIIa. The platelet-binding of RGD-modified liposomes was studied by fluorescence and scanning electron microscopy, and flow cytometry, in vitro. Binding of RGD-modified liposomes was also tested in vivo in a rat carotid injury model and analyzed ex vivo by fluorescence microscopy. The results from all experiments show that cyclic RGD-liposomes bind activated platelets significantly higher compared to linear RGD-liposomes. Hence, the results establish the feasibility of modulating the platelet-targeting and binding ability of vascularly targeted liposomes by manipulating the affinity of surface-modifying ligands. (c) 2008 Elsevier Ltd. All rights reserved.
Huang G F; Zhou Z M; Srinivasan R; Penn M S; Kottke-Marchant K; Marchant R E; Gupta A S
Biomaterials
2008
2008-04
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1016/j.biomaterials.2007.12.015" target="_blank" rel="noreferrer noopener">10.1016/j.biomaterials.2007.12.015</a>
Methamphetamine Produces Subsequent Reductions In Running Time To Exhaustion In Mice
brain; catecholamine; dopaminergic activity; exercise; fatigue; left ventricle; mechanisms; metabolism; Neurosciences & Neurology; nigrostriatal; performance; physical exercise; rats; responses; serotonin
Treatment with methamphetamine (MA - 20 mg/kgx4 i.p. at 2-h intervals) or its vehicle at 7 days prior to tests of running time to exhaustion were evaluated in 60-day-old CD-1 male mice. Pre-treatment running times were not significantly different between the two groups. MA resulted in significantly decreased running times to exhaustion compared to vehicle-treated controls and a significant reduction in corpus striatal dopamine and DOPAC but not norepinephrine. No statistically significant differences in catecholamines were obtained within the hypothalamus, or left ventricle of the heart, nor were body weights significantly different between these groups. The data show that a regimen of MA, which results in an approximate 90% depletion of striatal DA. produces a reduction in running time to exhaustion. (C) 2001 Elsevier Science B.V. All rights reserved.
Kalinski M I; Dluzen D E; Stadulis R
Brain Research
2001
2001-12
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1016/s0006-8993(01)03113-4" target="_blank" rel="noreferrer noopener">10.1016/s0006-8993(01)03113-4</a>
Differential Regulation Of Cysteinyl Leukotriene Receptor Signaling By Protein Kinase C In Human Mast Cells
activation; antagonist; asthmatic subjects; desensitization; expression; hyperresponsiveness; intestinal epithelial-cells; proliferation; pulmonary inflammation; responses; Science & Technology - Other Topics
Cysteinyl leukotrienes (cys-LTs) are a group of lipid mediators that are potent bronchoconstrictors, powerful inducers of vascular leakage and potentiators of airway hyperresponsiveness. Cys-LTs play an essential role in asthma and are synthesized as well as activated in mast cells (MCs). Cys-LTs relay their effects mainly through two known GPCRs, CysLT(1)R and CysLT(2)R. Although protein kinase C (PKC) isoforms are implicated in the regulation of CysLT(1)R function, neither the role of PKCs in cys-LT-dependent MC inflammatory signaling nor the involvement of specific isoforms in MC function are known. Here, we show that PKC inhibition augmented LTD4 and LTE4-induced calcium influx through CysLT(1)R in MCs. In contrast, inhibition of PKCs suppressed c-fos expression as well MIP1 beta generation by cys-LTs. Interestingly, cys-LTs activated both PKC alpha and PKC epsilon isoforms in MC. However, knockdown of PKC alpha augmented cys-LT mediated calcium flux, while knockdown of PKC epsilon attenuated cys-LT induced c-fos expression and MIP1 beta generation. Taken together, these results demonstrate for the first time that cys-LT signaling downstream of CysLT(1)R in MCs is differentially regulated by two distinct PKCs which modulate inflammatory signals that have significant pathobiologic implications in allergic reactions and asthma pathology.
Kondeti V; Duah E; Al-Azzam N; Thodeti C K; Boyce J A; Paruchuri S
Plos One
2013
2013-08
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1371/journal.pone.0071536" target="_blank" rel="noreferrer noopener">10.1371/journal.pone.0071536</a>
Hyperpolarizing And Depolarizing Gaba-a Receptor-mediated Dendritic Inhibition In Area Ca1 Of The Rat Hippocampus
activity-dependent disinhibition; cortical-neurons; depression; electrophysiology; gamma-aminobutyric acid; lacunosum-moleculare interneurons; morphology; Neurosciences & Neurology; Physiology; pyramidal cells-invitro; responses; voltage-clamp
1. Gamma-aminobutyric acid(A) (GABA(A)) receptor-mediated inhibition of pyramidal neuron dendrites was studied in area CA1 of the rat hippocampal slice preparation with the use of intracellular and extracellular recording and one-dimensional current source-density (CSD) analysis. 2. Electrical stimulation of Schaffer collateral/commissural fibers evoked monosynaptic excitatory postsynaptic potentials (EPSPs) and population EPSPs, which were followed by biphasic inhibitory postsynaptic potentials (IPSPs). In the presence of the excitatory amino acid receptor antagonists 6,7-dinitroquinoxaline-2,3-dione (DNQX) and D,L-2-amino-5-phosphonovalerate (APV), stimulation in stratum radiatum evoked monosynaptic fast, GABA(A) and late, GABA(B) receptor or-mediated IPSPs and fast and late positive field potentials recorded in s. radiatum. 3. Fast monosynaptic IPSPs and fast positive field potentials evoked in the presence of DNQX and APV were reversibly abolished by the GABA(A) receptor antagonist bicuculline methiodide (BMI; 30-mu-M) and were not changed by the GABA(B) receptor antagonist P-[3-aminopropyl]-P-diethoxymethylphosphinic acid (CGP 35 348; 0.1-1.0 mM). CGP 35 348 (0.1 mM) reversibly blocked late monosynaptic IPSPs and late positive field potentials. These results suggest that fast field potentials are GABA(A) receptor-mediated population IPSPs (GABA(A), fast pIPSPs) and that late field potentials are GABA(B) receptor-mediated population IPSPs (GABA(B), late pIPSPs). 4. Fast pIPSPs were reversibly abolished when the extracellular Cl- concentration ([Cl-1]o) was reduced from 132 to 26 mM in parallel with a depolarizing shift in the reversal potential of fast IPSPs. Paired or repetitive stimulation in s. radiatum reversibly depressed fast pIPSPs and fast IPSPs. Paired-pulse depression of fast pIPSPs was reversibly antagonized by CGP 35 348 (0.40. 8 mM). 5. Laminar analysis of s. radiatum-evoked fast pIPSPs and one-dimensional CSD analysis revealed active current sources in s. radiatum and passive current sinks in s. oriens and s. lacunosum moleculare. S. radiatum sources were abolished by pressure application of BMI in s. radiatum but not in s. oriens. Stimulation in s. oriens, s. pyramidale, or s. lacunosum moleculare evoked GABA(A) current sources horizontal to the stimulation site. Changes in the dendritic location of inhibitory current with changes in stimulus location paralleled changes in the distribution of excitatory current. 6. In the presence of 4-aminopyridine (50-100-mu-M), DNQX and APV long-lasting depolarizing GABA(A) receptor-mediated responses (LLDs) occurred spontaneously or could be evoked. Current sinks associated with s. radiatum-evoked LLDs were located in the same dendritic area as sources associated with hyperpolarizing fast IPSPs. 7. These results suggest that activation of GABA(A) receptors located on pyramidal neuron apical and basal dendrites produces outward Cl-1 current and hyperpolarizing IPSPs. This suggests that depolarizing responses to dendritic GABA application and orthodromic activation in area CA1 do not result from inward chloride current.
Lambert N A; Borroni A M; Grover L M; Teyler T J
Journal of Neurophysiology
1991
1991-11
Journal Article or Conference Abstract Publication
n/a