• Biomolecules & Therapeutics
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• v.21 no.2
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• pp.170-172
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• 2013

The pyrimidine nucleoside uridine has recently been reported to have a protective effect on cultured human corneal epithelial cells, in an animal model of dry eye and in patients. In this study, we investigate the pharmacokinetic profile of uridine in rabbits, following topical ocular (8 mg/eye), oral (450 mg/kg) and intravenous (100 mg/kg) administration. Blood and urine samples were serially taken, and uridine was measured by high-performance liquid chromatography-tandem mass spectrometry. No symptoms were noted in the animals after uridine treatment. Uridine was not detected in either plasma or urine after topical ocular administration, indicating no systemic exposure to uridine with this treatment route. Following a single intravenous dose, the plasma concentration of uridine showed a bi-exponential decay, with a rapid decline over 10 min, followed by a slow decay with a terminal half-life of $0.36{\pm}0.05$ h. Clearance and volume of distribution were $1.8{\pm}0.6$ L/h/kg and $0.58{\pm}0.32$ L/kg, respectively. The area under the plasma concentration-time curves (AUC) was $59.7{\pm}18.2{\mu}g{\cdot}hr/ml$, and urinary excretion up to 12 hr was ~7.7% of the dose. Plasma uridine reached a peak of $25.8{\pm}4.1{\mu}g/ml$ at $2.3{\pm}0.8$ hr after oral administration. The AUC was $79.0{\pm}13.9{\mu}g{\cdot}hr/ml$, representing ~29.4% of absolute bioavailability. About 1% of the oral dose was excreted in the urine. These results should prove useful in the design of future clinical and nonclinical studies conducted with uridine.

• Journal of Veterinary Clinics
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• v.38 no.3
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• pp.152-158
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• 2021

A 3-year-old spayed female beagle dog was presented with epiphora, severe hemorrhagic and purulent ocular discharge in the right eye (OD). A reflux of the discharge through the other canaliculi, associated with signs of chronic inflammation, was observed on cytology. Dacryocystorhinography revealed retention of contrast media ventral to the lower punctum, indicating complete obstruction and the potential presence of radiolucent foreign body. Ocular discharge subsided after the first treatment, including flushing of the nasolacrimal duct and application of topical antibiotics and corticosteroids, but clinical symptoms of the dacryocystitis waxed and waned thereafter. Surgical treatment was delayed for 8 months due to Dirofilaria immitis infection, and topical treatment and monthly flushing were maintained. On the day of operation, a foreign body was released through the fistula, while flushing for disinfection under general anesthesia, just before the surgery. Dacryocystectomy was performed to remove necrotic tissue and residual foreign body around the nasolacrimal cyst. Upon histopathologic findings, the removed foreign body was considered to be a plant, and the nasolacrimal cyst was comprised of chronic active ulcerative inflammation and necrotic tissues. At the 1-week recheck, improvement of epiphora and ocular discharge and healing of the surgical site was noted. In conclusion, nasolacrimal duct foreign body can be considered in recurrent dacryocystitis, despite nasolacrimal flushing and topical medication. In this study, dacryocystectomy was curative without recurrence of dacryocystitis or epiphora.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.59-66
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• 1994

The objective of this study was to determine the influence of drug lipophilicity on the extent of ocular and systemic absorption following topical solution instillation in the pigmented rabbit. ${\beta}-Blockers$ of various lipophilicity were chosen as model drugs, $25\;{\mu}l$ of a 15 mM drug solution in isotonic pH 7.4 buffer was instilled, and ocular tissue and plasma drug concentrations were monitored. Ocular absorption was apparently increased in all eye tissues, but non-corneal absorption ratio was decreased by increasing of drug lipophilicity. Systemic bioavailability was ranged from 61% for atenolol to 100% for timolol, and at least 50% of the systemically absorbed drug reached the blood stream from the nasal mucosa. Occluding the nasolacrimal duct for 5 min reduced the extent of systemic absorption of timolol and levobunolol, but did not do so for atenolol and betaxolol. Taken together, the ocular absorption of topically applied ophthalmic drugs would be modest for lipophilic drugs. By contrast, the systemic bioavailability would be modest for drugs at the extremes of lipophilicity, and the nasal contribution to systemically absorbed drug diminished with increasing of drug lipophilicity.

• Journal of Veterinary Clinics
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• v.37 no.5
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• pp.282-285
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• 2020

A 14-year-old neutered-male Shih-Tzu was referred for glaucoma and hyphema accompanied by systemic hypertension. After topical corticosteroid and antiglaucoma medications, the left eye (OS) progressed phthisically, but ocular hypertension redevelop one-year-and-seven-months later. Suspected limbal melanoma developed in peripheral cornea/limbal sclera with heavily pigmented cornea OS. Ultrasound biomicroscopy and ocular ultrasonography differentiated ciliary body origin-heterogeneous mass from limbal mass. Persistent hyphema and pigmented cornea might obscure intraocular lesion and advanced diagnostic methods played a crucial role. Unlike the generally benign limbal melanoma, aggressive treatment was recommended for uveal tumor. Histopathology of enucleated OS confirmed malignant uveal melanoma with chronic hypertensive vasculopathy.

• Journal of Veterinary Clinics
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• v.35 no.4
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• pp.161-165
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• 2018

A 12-year-old gelding Warmblood Horse was presented with a corneolimbal mass in the right eye (OD) of 6 months duration. Clinical signs included ocular discomfort, persistent mucoid ocular discharge, and conjunctival hyperemia. The mass was excised by superficial keratectomy under sedation in a standing position, followed by a topical application of 0.04% mitomycin C (MMC), and a placement of a conjunctival advancement graft. The histopathological diagnosis was squamous cell carcinoma. One month after surgery, recurrence of the mass was suspected upon examination of the eye. Topical MMC and 5-fluorouracil followed by cryotherapy were applied as adjunctive therapies after debulking of the mass. The surgical site healed without complications and with a cosmetically acceptable result. No recurrence of the mass was noted four years following the second procedure.

• Journal of Veterinary Clinics
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• v.37 no.5
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• pp.286-291
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• 2020

A 15-year-old castrated male Persian (Case 1), an 1.5-year-old castrated male Bengal (Case 2), and an 1.5-year-old spayed female Russian Blue (Case 3) cats were presented with iris-color change and suspicious anterior chamber mass. Complete ophthalmic examination revealed a vascularized or blood tinted mass filling with anterior chamber accompanied by rubeosis iridis, dyscoria, keratic precipitates, and severe aqueous flare. Ocular ultrasonography showed an iridociliary mass with blood flow signal in Case 1. Abdominal ultrasonography also revealed suspicious metastatic involvements of liver and spleen in this cat. Case 2 and 3 were suspected of being infected with feline infectious peritonitis. Topical antibiotic/steroid combinations were prescribed to control the uveitis in all 3 cases, although enucleation was initially considered for palliative pain management in Case 1. Anterior chamber mass had almost completely disappeared after topical medications and uveitis has been successfully managed, remaining in sight, even though ocular hypertension developed 1 month later in Case 1.

• Journal of Environmental Science International
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• v.26 no.2
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• pp.249-256
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• 2017

In this study, we evaluated the potential of 70% ethanol extract from Persicaria nepalensis (PNE) as a cosmetic ingredient by primary skin irritation, ocular irritation, and maximization tests for delayed hypersensitivity in New Zealand white rabbits and Hartley guinea pig. Skin safety study was performed to evaluate the potential toxicity of PNE using the primary irritation test. In the primary irritation test, 50% PNE was applied to the skin, and no adverse reactions such as erythema and edema were observed at the intact skin sites. Therefore, PNE was classified as a practically non-irritating material based on a primary irritation index of "0.0.". In the ocular irritation test, the 50% PNE applied did not show any adverse reactions in the different parts of rabbit eyes, including the cornea, iris, and conjunctiva. Thus, PNE was classified as a practically non-irritating material based on an acute ocular irritation index of "0.0.". Skin sensitization was tested by the Guinea Pig Maximization Test (GPMT) and Freund's Complete Adjuvant (FCA) using an intradermal injection of 10% PNE. Edema and erythema were not observed 24 and 48 h after the topical application of PNE in skin sensitization test, which exhibited a sensitization score of "0.0.". Therefore, it can be suggested that P. nepalensis could be used as potential candidates for cosmoceutical ingredients, without any major side effects.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.295.2-295.2
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• 2003

Lipid nanodispersion (LN) composed of biocompatible lipids and surfactants is an alternative parenteral drug delivery system especially for lipophilic drugs. It has been studied for versatile applications such as oral, parenteral, topical, ocular, vaccine, and peptide drug delivery. The purpose of this study was to produce a novel LN system for intravenous injection using the high pressure homogenization. (omitted)

• Toxicological Research
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• v.14 no.2
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• pp.217-226
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• 1998

SDK (skin decontamination kit) is new skin decontaminant which is developed by ADD (Agency for defence development). In this study, four-week toxicity of SDK was investigated using beagle dogs and Sprague-Dawley rats. The beagle dogs and Sprague-Dawley rats were dressed topically seven days per week for 28 days, with dosage of 0, 0.25, 0.8 and 1 g/kg/day. respectively. Animals treated with SDK did not cause any death and show any clinical signs. They did not show any significant changes of body weight, feed uptake and water consumption. They were not significantly different from the control group in urinalysis, ocular examination and histopathological examination. In hematological and serum biochemical assay, there were no-dose-defendent changes. Therefore, SDK was not indicated to have any toxic effect in the beagle dogs and Sprague-Dawley rats when it was dressed topically below the dosage 1 g/kg/day for four weeks.

• Journal of Veterinary Clinics
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• v.37 no.5
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• pp.292-294
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• 2020

A 14-year-old castrated male Persian cat presented with epiphora, blepharospasm, brownish ocular discharge, corneal neovascularization, and corneal opacity in the left eye. Medial lower eyelid entropion was diagnosed through an ophthalmic examination. Since the cat was old and suffered from chronic kidney disease, we decided to perform a hyaluronic acid (HA) subdermal filler injection without general anesthesia rather than surgical correction. After topical anesthesia by lidocaine jelly and disinfection, HA filler was injected into the medial lower eyelid under minimal physical restraint. At the last follow-up 139 days later, lower eyelid entropion was not observed and related clinical signs disappeared. Therefore, HA subdermal filler can be an effective intervention for the treatment of entropion in cats.