• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1937-1945
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• 2018

Malassezia pachydermatis is a commensal yeast found on the skin of dogs. However, M. pachydermatis is also considered an opportunistic pathogen and is associated with various canine skin diseases including otitis externa and atopic dermatitis, which usually require treatment using an azole antifungal drug, such as ketoconazole. In this study, we isolated a ketoconazole-resistant strain of M. pachydermatis, designated "KCTC 27587," from the external ear canal of a dog with otitis externa and analyzed its resistance mechanism. To understand the mechanism underlying ketoconazole resistance of the clinical isolate M. pachydermatis KCTC 27587, the whole genome of the yeast was sequenced using the PacBio platform and was compared with M. pachydermatis type strain CBS 1879. We found that a ~84-kb region in chromosome 4 of M. pachydermatis KCTC 27587 was tandemly quadruplicated. The quadruplicated region contains 52 protein coding genes, including the homologs of ERG4 and ERG11, whose overexpression is known to be associated with azole resistance. Our data suggest that the quadruplication of the ~84-kb region may be the cause of the ketoconazole resistance in M. pachydermatis KCTC 27587.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2006.05a
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• pp.115-115
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• 2006

• Journal of Veterinary Clinics
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• v.28 no.2
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• pp.196-203
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• 2011

Staphylococcus spp. is one of the most common bacteria isolated from the lesions of atopic dermatitis (AD) in humans, and their colonization is known to be a possible trigger factor of clinical signs. The aim of this study was to determine the prevalence of Staphylococcus spp. in canine AD (CAD), the types of exotoxins present, and their relation with the clinical severity of CAD. From 79 dogs with AD, 72 samples of Staphylococcus spp. were isolated (91.1%), and 65 (90.3%) were confirmed as Staphylococcus pseudintermedius. Concerning the profile of the exotoxin gene, 50 isolates (69.4%) contained at least one exotoxin gene, and 28 isolates (56%) were found to contain more than 2 different exotoxins. There was a significant difference in clinical severity with the presence of staphylococcal exotoxins (P=0.028), whereas no correlation was found with the presence of Staphylococcus spp. (P=0.598). The clinical severity of CAD increased only in relation to staphylococcal enterotoxin D (SED) and exfoliative toxins (P<0.05). Some clinical evaluation criteria (erythema, papule/pustule) were correlated with the presence of the exotoxin gene (P<0.05). This study showed that the high prevalence of Staphylococcus spp. and staphylococcal exotoxins in lesions from dogs with AD may be regarded as an important trigger factor for exacerbation of the clinical signs of CAD.

• Journal of Veterinary Clinics
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• v.19 no.2
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• pp.186-190
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• 2002

This crossover study was performed in order to compare the effects of cetirizine, loratadine, and terfenadine in canine skin. Five healthy dogs were used. Cetirizine 0.5 mg/kg, loratadine 5 mg/kg and terfenadine 5 mg/kg were administered orally 4 hours before the experiment. Erythema indices and wheal size were assessed by Hexameter ($MX^{\circledR}$ 18, CK, Germany) and skin reaction guide, respectively. Cetirizine-induced erythema inhibition was generally higher than other drugs and was significantly different from placebo. Cetirizine was superior to placebo at 3, 4, 5, 6, 7, and 8 minutes (p< 0.01). Cetirizine also was superior to placebo at 9 minutes (p< 0.05). Loratadine and terfenadine erythema inhibition were better than after placebo treatment from 4 to 9 minutes, but erythema index of terfenadine at 7 minutes was not observed probability of 95% and 99%. At 10 minutes, intradermal injection of the histamine caused a mean wheal dimension for placebo, cetirizine, loratadine and terfenadine, which were 13.25$\pm$0.75 mm,7.5$\pm$ 1.02 mm (53% reduction, p<0.007),6.2$\pm$0.58 mm(43% reduction, p <0.01), and 8.4 $\pm$0.67 mm(37% reduction, p< 0.05), respectively, comparing with placebo. Loratadine and cetirizine were good antihistamines for clinical therapy for atopic dermatitis in dog.

• Journal of Veterinary Clinics
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• v.25 no.5
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• pp.330-339
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• 2008

Ceramide, cholesterol and free fatty acids are the major intercellular lipids, maintaining the integrity of the skin barrier. However, the roles of these lipids in canine skin barrier function are little known. The aim of this study was to evaluate the repairing effects of 2% ceramide (CER), 2% cholesterol (CHO), 2% linoleic acid (LIN) and 2% intercellular lipid mixture (ILM) on damaged canine skin barrier by 1.25% sodium lauryl sulphate (SLS). Transepidermal water loss (TEWL), skin hydration, skin pH and skin thickness were assessed. Histological profiles and transmission electron microscopic (TEM) profiles were assessed on day 12. SLS effectively induced the canine skin barrier damage. TEWL was significantly decreased by topical application of CER and ILM in SLS and vehicle-treated skin on day 8 and 12, respectively (p < 0.05, p < 0.0 I). By end of the experiment all lipids significantly decreased the TEWL as compared with SLS and vehicle control, but CER and ILM more significantly decreased the TEWL than UN and CHO, respectively (p < 0.01). Skin hydration was significantly increased by CER and ILM during experimental periods (p < 0.01). Skin pH was significantly decreased by CER, LIN and ILM. In histological profiles, the thickness of the stratum corneum (SC) was significantly increased by the SC lipids as compared with vehicle and SLS (p < 0.01). Especially, CER and ILM showed more prominent improvement of barrier recovery. In TEM of the SC, SLS induced exfoliations of corneodesmosomes in the SC, and CER and ILM effectively protected exfoliations of corneodesmosomes on SLS-damaged canine skin. These results indicated that topical application of CER and ILM dramatically improved damaged-skin barrier function by SLS. Also, it was considered that the use of CER or ILM was recommended for the management of skin barrier dysfunction by irritant and inflammatory skin disorders such as atopic dermatitis.

• Journal of Veterinary Clinics
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• v.29 no.4
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• pp.283-296
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• 2012

Allergic contact dermatitis (ACD) is an inflammatory skin disease and regarded as a prototype of T-cell mediated delayed-type hypersensitivity reactions. Poly-${\gamma}$-glutamic acid (PGA) is a biodegradable polymer that is produced by Bacillus subtilis. This study was performed to assess the effects of PGA in a canine model of ACD. ACD was induced on the back of dogs induced by sensitization and repeated application by 2,4-dinitro-1-chlorobenzene (DNCB). Topical treatment of PGA was applied once a day for 12 days and skin biophysical parameters including transepidermal water loss (TEWL), skin hydration, skin pH, skin thickness and erythema index, were measured every two days during experimental periods. Histopathology and immunohistochemistry were performed to evaluate the antiinflammatory effect. In skin biophysical parameters, TEWL, skin hydration, skin thickness and erythema index were significantly increased, with a maximum increase appeared on day 2 (p < 0.05). On the other hand, skin pH was significantly decreased, with a maximum decrease appeared on day 2 (p < 0.01). After the completion of PGA treatment, skin biophysical parameters were significantly reached those of baseline in a time-dependent manner (p < 0.05). In histopathology, marked increases of epidermal thicknesses were induced after DNCB challenge with numerous inflammatory cell infiltrations and edematous changes, decreases of connective tissue occupied regions in dermis. In addition, marked increases of cytokine - tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interferon-${\gamma}$ (IFN-${\gamma}$)-immunoreactivities in the dermis and of apoptotic markers - caspase-3 and PARP-immunoreactivities in the epidermis were observed in DNCB-PBS control as compared with intact control, respectively (p < 0.01). It means, the ACD and related apoptotic changes were induced by DNCB in the present study. However, these ACD induced by DNCB and related apoptosis in epidermis were significantly inhibited by treatment of PGA treated skin, the decreases of infiltrated inflammatory cells and related decreases of pro-inflammatory cytokine immunoreactivities were also observed (p < 0.01). Based on these findings, PGA may have anti-inflammatory and alleviatory effects in the allergic contact dermatitis.

• Journal of Veterinary Clinics
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• v.38 no.2
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• pp.56-62
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• 2021

Madecassoside, an active ingredient extracted from Centella asiatica, is used for treatment of various skin disorders in humans. However, the effect of madecassoside on the skin of dogs and cats has not been studied yet. The purpose of this study was to evaluate clinical efficacy of topical madecassoside cream in dogs and cats with skin diseases. A total of twenty-one dogs and ten cats with various skin diseases were included in the study. The 1% topical madecassoside cream was applied to the animal's skin lesion at least once a day for 7 days, and the skin condition was evaluated before the application of madecassoside cream (day 0) and 7 days after the application (day 7). The skin condition was scored by five clinical indices: canine atopic dermatitis extent and severity index-4 (CADESI-4), coat condition, pruritus, scale, and general condition. In dogs, all five clinical indices (CADESI-4, coat condition, pruritus, scale, and general condition) were significantly decreased on day 7 compared to those on day 0 (p < 0.0001, p < 0.05, p < 0.001, p < 0.01, and p < 0.05, respectively). In cats, the CADESI-4 and scale were significantly decreased on day 7 compared to those on day 0 (p < 0.01 and p < 0.05, respectively). No adverse effects were observed during the trial period in the dogs and cats included in this study. The results of this study demonstrate that the topical madecassoside cream is applicable to skin lesions in dogs and cats.