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Articles 31 - 47 of 47

Full-Text Articles in Musculoskeletal, Neural, and Ocular Physiology

Vector Delivery Technique Affects Gene Transfer In The Cornea In Vivo, Rajiv R. Mohan, Ajay Sharma, Tyler C. Cebulko, Ashish Tandon Jan 2010

Vector Delivery Technique Affects Gene Transfer In The Cornea In Vivo, Rajiv R. Mohan, Ajay Sharma, Tyler C. Cebulko, Ashish Tandon

Pharmacy Faculty Articles and Research

Purpose: This study tested whether controlled drying of the cornea increases vector absorption in mouse and rabbit corneas in vivo and human cornea ex vivo, and studied the effects of corneal drying on gene transfer, structure and inflammatory reaction in the mouse cornea in vivo.

Methods: Female C57 black mice and New Zealand White rabbits were used for in vivo studies. Donor human corneas were used for ex vivo experiments. A hair dryer was used for drying the corneas after removing corneal epithelium by gentle scraping. The corneas received no, once, twice, thrice, or five times warm air for …


"Transduction Efficiency Of Aav 2/6, 2/8 And 2/9 Vectors For Delivering Genes In Human Corneal Fibroblasts ", Ajay Sharma, Arkasubhra Ghosh, Eric T. Hansen, Jason M. Newman, Rajiv R. Mohan Jan 2010

"Transduction Efficiency Of Aav 2/6, 2/8 And 2/9 Vectors For Delivering Genes In Human Corneal Fibroblasts ", Ajay Sharma, Arkasubhra Ghosh, Eric T. Hansen, Jason M. Newman, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

In the present study, cellular tropism and relative transduction efficiency of AAV2/6, AAV2/8 and AAV2/9 vectors have been tested for the cornea using primary cultures of human corneal fibroblasts. The AAV6, AAV8 and AAV9 serotypes having AAV2 ITR plasmid encoding for alkaline phosphatase (AP) gene were generated by transfecting HEK293 cell line with pHelper, pARAP4 and pRep/Cap plasmids. Primary cultures of human corneal fibroblasts were exposed to AAV infectious particles at two different doses (1×105 and 2×105 MOI). Cytochemistry and enzyme assays were used to measure delivered transgene expression in samples collected at 4 and 30 hours after AAV infection …


Role Of Transforming Growth Factor Beta In Corneal Function, Biology And Pathology, Ashish Tandon, Jonathan C. K. Tovey, Ajay Sharma, Rangan Gupta, Rajiv R. Mohan Jan 2010

Role Of Transforming Growth Factor Beta In Corneal Function, Biology And Pathology, Ashish Tandon, Jonathan C. K. Tovey, Ajay Sharma, Rangan Gupta, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Transforming growth factor-beta (TGFβ) is a pleiotropic multifunctional cytokine that regulates several essential cellular processes in many parts of the body including the cornea. Three isoforms of TGFβ are known in mammals and the human cornea expresses all of them. TGFβ1 has been shown to play a central role in scar formation in adult corneas whereas TGFβ2 and TGFβ3 have been implicated to play a critical role in corneal development and scarless wound healing during embryogenesis. The biological effects of TGFβ in the cornea have been shown to follow SMAD dependent as well as SMAD-independent signaling pathways depending upon cellular …


Efficacy And Safety Of Mitomycin C As An Agent To Treat Corneal Scarring In Horses Using An In Vitro Model, Dylan G. Buss, Ajay Sharma, Elizabeth A. Giuliano, Rajiv R. Mohan Jan 2010

Efficacy And Safety Of Mitomycin C As An Agent To Treat Corneal Scarring In Horses Using An In Vitro Model, Dylan G. Buss, Ajay Sharma, Elizabeth A. Giuliano, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Objective—Mitomycin C (MMC) is used clinically to treat corneal scarring in human patients. We investigated the safety and efficacy of MMC to treat corneal scarring in horses by examining its effects at the early and late stages of disease using an in-vitro model.

Procedure—An in-vitro model of equine corneal fibroblast (ECF) developed was used. The equine corneal fibroblast or myofibroblast cultures were produced by growing primary ECF in the presence or absence of transforming growth factor beta-1 (TGFβ1) under serum-free conditions. The MMC dose for the equine cornea was defined with dose-dependent trypan blue exclusion and MTT [(3-4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assays …


Localization Of Angiotensin Converting Enzyme In Rabbit Cornea And Its Role In Controlling Corneal Angiogenesis In Vivo, Ajay Sharma, Daniel I. Bettis, John W. Cowden, Rajiv R. Mohan Jan 2010

Localization Of Angiotensin Converting Enzyme In Rabbit Cornea And Its Role In Controlling Corneal Angiogenesis In Vivo, Ajay Sharma, Daniel I. Bettis, John W. Cowden, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Purpose: The renin angiotensin system (RAS) has been shown to modulate vascular endothelial growth factor and angiogenesis. In this study we investigated (i) the existence of the RAS components angiotensin converting enzyme (ACE) and angiotensin II receptors (AT1 and AT2) in the rabbit cornea using in vitro and ex vivo models and (ii) the effect of enalapril, an ACE inhibitor, to inhibit angiogenesis in rabbit cornea in vivo.

Methods: New Zealand White rabbits were used. Cultured corneal fibroblasts and corneal epithelial cells were used for RNA isolation and cDNA preparation using standard molecular biology techniques. PCR was performed to …


Gene Delivery In The Equine Cornea: A Novel Therapeutic Strategy, Dylan G. Buss, Ajay Sharma, Elizabeth A. Giuliano, Rajiv R. Mohan Jan 2010

Gene Delivery In The Equine Cornea: A Novel Therapeutic Strategy, Dylan G. Buss, Ajay Sharma, Elizabeth A. Giuliano, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Objective—To determine if hybrid adeno-associated virus serotype 2/5 (AAV5) vector can effectively deliver foreign genes into the equine cornea without causing adverse side effects. The aims of this study were to: (i) evaluate efficacy of AAV5 to deliver therapeutic genes into equine corneal fibroblasts (ECFs) using enhanced green fluorescent protein (EGFP) marker gene and (ii) establish the safety of AAV5 vector for equine corneal gene therapy.

Animal Material—Primary ECF cultures were harvested from healthy donor equine corneas. Cultures were maintained at 370C in humidified atmosphere with 5% CO2.

Procedure—AAV5 vector expressing EGFP under control of hybrid cytomegalovirus (CMV) + chicken …


Isolation And Cultivation Of Equine Corneal Keratocytes, Fibroblasts And Myofibroblasts, Dylan G. Buss, Elizabeth A. Giuliano, Ajay Sharma, Rajiv R. Mohan Jan 2010

Isolation And Cultivation Of Equine Corneal Keratocytes, Fibroblasts And Myofibroblasts, Dylan G. Buss, Elizabeth A. Giuliano, Ajay Sharma, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Objective—To establish an in vitro model for the investigation of equine corneal wound healing. To accomplish this goal, a protocol to isolate and culture equine corneal keratocytes, fibroblasts and myofibroblasts was developed.

Animal material—Equine corneal buttons were aseptically harvested from healthy research horses undergoing humane euthanasia for reasons unrelated to this study. Slit-lamp biomicroscopy was performed prior to euthanasia by a board-certified veterinary ophthalmologist to ensure that all samples were harvested from horses free of anterior segment disease.

Procedure—Equine corneal stroma was isolated using mechanical techniques and stromal subsections were then cultured. Customized media at different culture conditions was used …


Aav Serotype Influences Gene Transfer In Corneal Stroma In Vivo, Ajay Sharma, Jonathan C. K. Tovey, Arkasubhra Ghosh, Rajiv R. Mohan Jan 2010

Aav Serotype Influences Gene Transfer In Corneal Stroma In Vivo, Ajay Sharma, Jonathan C. K. Tovey, Arkasubhra Ghosh, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

This study evaluated the cellular tropism and relative transduction efficiency of three AAV serotypes, AAV6, AAV8 and AAV9, for corneal gene delivery using mouse cornea in vivo and donor human cornea ex vivo. The AAV6, AAV8 and AAV9 serotypes having AAV2 plasmid encoding for alkaline phosphatase (AP) gene were generated by transfecting HEK293 cell line with pHelper, pARAP4 and pRep/Cap plasmids. Viral vectors (109 vg/μl) were topically applied onto mouse cornea in vivo and human cornea ex vivo after removing the epithelium. Human corneas were processed for transgene delivery at day 5 after viral vector application. Mouse corneas were harvested …


Performance Of A Hip Protector Depends On Its Position During A Fall, Woochol J. Choi, Joaquin A. Hoffer, Stephen N. Robinovitch Aug 2009

Performance Of A Hip Protector Depends On Its Position During A Fall, Woochol J. Choi, Joaquin A. Hoffer, Stephen N. Robinovitch

Physical Therapy Faculty Articles and Research

"Hip protectors are designed to attenuate and redistribute the force applied to the hip region during a fall, and thereby reduce risk for hip fracture [1]. However, little information exists on the effectiveness of hip protectors in achieving these goals, and how this is altered by displacement of the hip protector relative to the greater trochanter (GT). In the current study, we tested these issues."


Trichostatin A Inhibits Corneal Haze In Vitro And In Vivo, Ajay Sharma, Maneesh M. Mehan, Sunilima Sinha, John W. Cowden, Rajiv R. Mohan Jan 2009

Trichostatin A Inhibits Corneal Haze In Vitro And In Vivo, Ajay Sharma, Maneesh M. Mehan, Sunilima Sinha, John W. Cowden, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

PURPOSE. Trichostatin A (TSA), a histone deacetylase inhibitor, has been shown to suppress TGF- –induced fibrogenesis in many nonocular tissues. The authors evaluated TSA cytotoxicity and its antifibrogenic activity on TGF- –driven fibrosis in the cornea with the use of in vitro and in vivo models.

METHODS. Human corneal fibroblasts (HSFs) were used for in vitro studies, and New Zealand White rabbits were used for in vivo studies. Haze in the rabbit cornea was produced with photorefractive keratectomy (PRK) using excimer laser. Trypan blue exclusion and MTT assays evaluated TSA cytotoxicity to the cornea. Density of haze in the rabbit …


Three-Dimensional Arm Movements At Constant Equi-Affine Speed, Frank E. Pollick, Uri Maoz, Amir A. Handzel, Peter J. Giblin, Guillermo Sapiro, Tamar Flash Jun 2008

Three-Dimensional Arm Movements At Constant Equi-Affine Speed, Frank E. Pollick, Uri Maoz, Amir A. Handzel, Peter J. Giblin, Guillermo Sapiro, Tamar Flash

Psychology Faculty Articles and Research

It has long been acknowledged that planar hand drawing movements conform to a relationship between movement speed and shape, such that movement speed is inversely proportional to the curvature to the power of one-third. Previous literature has detailed potential explanations for the power-law’s existence as well as systematic deviations from it. However, the case of speed-shape relations for three-dimensional (3D) drawing movements has remained largely unstudied. In this paper we first derive a generalization of the planar power law to 3D movements, which is based on the principle that this power law implies motion at constant equi-affine speed. This generalization …


Pdgf-Driven Proliferation, Migration, And Il8 Chemokine Secretion In Human Corneal Fibroblasts Involve Jak2-Stat3 Signaling Pathway, Neeraj Vij, Ajay Sharma, Mahesh Thakkar, Sunilima Sinha, Rajiv R. Mohan Jan 2008

Pdgf-Driven Proliferation, Migration, And Il8 Chemokine Secretion In Human Corneal Fibroblasts Involve Jak2-Stat3 Signaling Pathway, Neeraj Vij, Ajay Sharma, Mahesh Thakkar, Sunilima Sinha, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Purpose: Platelet-derived growth factor (PDGF) is associated with corneal fibroblast migration and proliferation and plays an important role in corneal wound healing. However, the intracellular mechanisms of PDGF-mediated functions in corneal fibroblasts are poorly understood. We tested the hypothesis that PDGF functional activities in the cornea involve the Janus kinase-2/signal transducers and activators of transcription-3 (JAK2-STAT3) signaling pathway and whether PDGF induces the expression of suppressors of cytokine signaling 3 (SOCS3), belonging to the novel family of feedback regulators of cytokine and growth factor activities.

Methods: Human corneal fibroblast (HSF) cultures were used as an in vitro model for functional …


Stromal Haze, Myofibroblasts, And Surface Irregularity After Prk, Marcelo V. Netto, Rajiv R. Mohan, Sunilima Sinha, Ajay Sharma, William Dupps, Steven E. Wilson Jan 2006

Stromal Haze, Myofibroblasts, And Surface Irregularity After Prk, Marcelo V. Netto, Rajiv R. Mohan, Sunilima Sinha, Ajay Sharma, William Dupps, Steven E. Wilson

Pharmacy Faculty Articles and Research

The aim of this study was to investigate the relationship between the level of stromal surface irregularity after photorefractive keratectomy (PRK) and myofibroblast generation along with the development of corneal haze.

Variable levels of stromal surface irregularity were generated in rabbit corneas by positioning a fine mesh screen in the path of excimer laser during ablation for a variable percentage of the terminal pulses of the treatment for myopia that does not otherwise generate significant opacity. Ninety-six rabbits were divided into eight groups[.]

Slit lamp analysis and haze grading were performed in all groups. Rabbits were sacrificed at 4 hr …


Effect Of Prophylactic And Therapeutic Mitomycin C On Corneal Apoptosis, Cellular Proliferation, Haze, And Long-Term Keratocyte Density In Rabbits, Marcelo V. Netto, Rajiv R. Mohan, Sunilima Sinha, Ajay Sharma, Pankaj C. Gupta, Steven E. Wilson Jan 2006

Effect Of Prophylactic And Therapeutic Mitomycin C On Corneal Apoptosis, Cellular Proliferation, Haze, And Long-Term Keratocyte Density In Rabbits, Marcelo V. Netto, Rajiv R. Mohan, Sunilima Sinha, Ajay Sharma, Pankaj C. Gupta, Steven E. Wilson

Pharmacy Faculty Articles and Research

PURPOSE—To determine the mechanism through which topical mitomycin C prevents and treats corneal haze after photorefractive keratectomy (PRK) and to examine the effects of dosage and duration of exposure.

METHODS—In 224 New Zealand rabbits, −9.0 diopter PRK with mitomycin C or balanced salt solution was performed. Haze level was graded at the slit-lamp. Rabbits were sacrificed at 4 hours, 24 hours, 4 weeks, or 6 months after surgery and immunohistochemistry was performed with TUNEL assay, Ki67 and α-SMA.

RESULTS—TUNEL-positive apoptotic cells marginally increased in all mitomycin C groups whereas Ki67-positive mitotic cells decreased significantly following mitomycin C application. A greater …


Polymerase Chain Reaction: An Emerging Tool For Research In Pharmacology, Rishi Sharma, Manjeet Singh, Ajay Sharma Jan 2002

Polymerase Chain Reaction: An Emerging Tool For Research In Pharmacology, Rishi Sharma, Manjeet Singh, Ajay Sharma

Pharmacy Faculty Articles and Research

Polymerase chain reaction (PCR) is a technique that can amplify a specific DNA segment in vitro using two site specific primers that hybridise to opposite DNA strands. The method produces large amounts of specific DNA from a complex DNA template in a single enzymatic reaction within a matter of hours. Reaction mixture contains a double helix DNA, two target specific primers, dNTPs, a DNA polymerase and a Mg2+ containing buffer. PCR is carried out in three distinct steps i.e. denaturation step, annealing step and extension step, which are repeated many times. The efficiency of PCR is measured in terms of …


Role Of KAtp Channels In Reduced Antinociceptive Effect Of Morphine In Streptozotocin-Induced Diabetic Mice, Vivek Sood, Ajay Sharma, Manjeet Singh Jan 2000

Role Of KAtp Channels In Reduced Antinociceptive Effect Of Morphine In Streptozotocin-Induced Diabetic Mice, Vivek Sood, Ajay Sharma, Manjeet Singh

Pharmacy Faculty Articles and Research

The nociceptive effect was measured using withdrawal latency in tail flick test in mice rendered diabetic by administering streptozotocin (200 mg/kg, i.p.). The antinociceptive effect of morphine (4 and 8 mg/kg, s.c.) and cromakalim, a KATP channel opener, (0.3, 1 and 2 micrograms, i.c.v.) was significantly reduced in diabetic mice. Moreover, co-administration of cromakalim(0.3 microgram) did not alter the reduced antinociceptive effect of morphine(4 mg/kg) in diabetic mice. Spleenectomy in diabetic mice restored the decrease in antinociceptive effect of morphine and cromakalim. Multiple dose treatment with insulin to maintain euglycaemia for 3 days in diabetic mice prevented the decrease in …


Effect Of Actinomycin D And Cycloheximide On Ischemic Preconditioning-Induced Delayed Cardioprotective Effect In Rats, Devinder Singh, Ajay Sharma, Manjeet Singh Jan 2000

Effect Of Actinomycin D And Cycloheximide On Ischemic Preconditioning-Induced Delayed Cardioprotective Effect In Rats, Devinder Singh, Ajay Sharma, Manjeet Singh

Pharmacy Faculty Articles and Research

The present study was designed to investigate the effect of actinomycin D, a transcription inhibitor, and cycloheximide, a translation inhibitor, on the delayed cardioprotective effect of ischemic preconditioning. Left thoracotomy was performed in anaesthetized rats at 4th/5th intercostal space and polypropylene suture (5-0) was employed to occlude left common coronary artery. Ischemic preconditioning was produced by four episodes of 5 min of coronary artery occlusion followed by 5 min of reperfusion and thoracic cavity was sutured. Left thoracotomy was performed again after 24 hr of ischemic preconditioning and left coronary artery was occluded for 30 min followed by reperfusion for …