Ki-Jeong Na

A Simple and Improved DNA Test for Avian Sex Determination

ABSTRACT. Determining the sex of a bird on the basis of its morphological characteristics is difficult in >50% of avian species; in nestlings, this rate is even higher. Given that male birds have two identical sex chromosomes (ZZ), whereas females are heterogametic (ZW), the development of a DNA-based sexing method has been widely investigated in several species. Griffiths et al. (1998) reported a simple DNA test using intronic size variation; however, this method cannot differentiate birds that have small or nonexistent size variations. We report a simple and novel DNA test for avian sex determination using a novel primer (p0) specific for the unique sequence of the chromohelicase-DNA-binding (CHD)-W gene. Use of a multiplex polymerase chain reaction (PCR) and simple agarose-gel electrophoresis with p0 and with the primers P2 and P8 described by Griffiths et al. (1998) revealed that the P0–P2 combination could amplify the partial CHD-W gene alone. Consequently, we found that p0 could be used to identify only the CHD-W gene. We anticipate that this multiplex PCR will be useful for universal avian sexing, regardless of the intronic size variation.

High prevalence of Theileria sp. in wild Chinese Water Deer (Hydropotes inermis argyropus) in South Korea.

Wild Chinese Water Deer exist in large numbers in Northeast Asia, including South Korea. The deer population is so widespread that they are common even in urban areas, resulting in increased contact with humans and domestic animals. The purpose of this study was to examine the prevalence of Theileria sp. infection in wild Chinese Water Deer in South Korea. Using biomolecular techniques, blood samples taken from 18 wild Chinese Water Deer were examined. Thirteen of the 18 samples (72%) tested positive for infection. In 11 of the deer, a Theileria sp. was detected that is nearly identical to the highly pathogenic Theileria sp. reported in China. Theileria ovis and Theileria capreoli were also detected individually in two deer. These results indicate that there may be a high prevalence of Theileria sp. infection in wild Chinese Water Deer, and that the deer may act as a reservoir for the Theileria sp. infection of domestic animals.

Dysregulation of the Wnt/Β-Catenin Signaling Pathway in Canine Cutaneous Melanotic Tumor

The Wnt/β-catenin signal transduction pathway is important in many developmental processes and during tumorigenesis. β-Catenin acts as a signal transducer. To investigate whether the Wnt/β-catenin signal transduction pathway is involved in canine cutaneous melanomagenesis, 18 formalin-fixed paraffin-embedded canine cutaneous melanotic tumor tissues were examined. For cloning and sequencing of the full-length canine ctnnb1 gene encoding β-catenin, conserved sequences of the human and mouse ctnnb1 gene were used to design the primers. For analysis of expression and translocation of β-catenin in canine cutaneous melanotic tumors, semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry were performed. The canine ctnnb1 sequence showed a high degree of similarity to those of human and mouse. Semiquantitative RT-PCR showed a substantial increase in expression of ctnnb1 mRNA in canine cutaneous melanotic tumors compared to normal canine melanocytes, regardless of whether the tumor was benign or malignant. Immunohistochemistry revealed cytoplasmic accumulation of β-catenin in melanotic tumors. In melanoma tissues, nuclear translocation of β-catenin was also observed. The present study demonstrated that abnormal intracellular accumulation and substantially increased expression of β-catenin are involved in canine cutaneous melanotic tumor.

Protective effects of the pyrolyzates derived from bamboo against neuronal damage and hematoaggregation

ETHNOPHARMACOLOGICAL RELEVANCE Bamboo species are thought to be originally from Central China, but are now found in many temperate and semi-tropical regions around the world. Although the extracts from bamboo may have antioxidant activities and anti-inflammatory effects, their exact biological activities have not been elucidated. AIM OF THE STUDY Two biological activities of bamboo-derived pyrolyzates were investigated; the protective effects against N-methyl-d-aspartate (NMDA)-induced cell death in primary cultured cortical neuron and the anti-plasmin effects determined by using fibrin and fibrinogen degradation products (FDPs) assay. RESULTS Treatment of neuronal cells with pyrolyzates of Phyllostachys pubescens, Phyllostachys nigra and Phyllostachys bambusoides resulted in restored cell viability when compared to untreated cells in an NMDA-induced neuronal cell death assay. In addition, cortical neurons treated with Phyllostachys pubescens and Phyllostachys nigra showed a reduction of apoptosis following exposure to NMDA, as determined by Hoechst 33342 staining. In addition, Phyllostachys nigra pyrolyzates also exhibited anti-plasmin action in a FDP assay. It is of interest to note that pyrolyzates exhibited activities of NMDA-receptor antagonist and antifebrin (ogen), since a combination of NMDA receptor antagonists, glucocorticosteroids, GABAergic drugs and heparin are useful for treatment in delayed postischemic injury. CONCLUSION Our results indicate that the pyrolyzates derived from bamboo may have anti-apoptotic effects, and can be useful as a supplement for ischemic injury treatment.

Molecular Detection of Theileria sp. in Wild Chinese Water Deer (Hydropotes inermis argyropus)

Two cases of Theileria sp. infection in wild Chinese water deer (Hydropotes inermis argyropus) were diagnosed by microscopic examination of thin blood smears and by molecular typing. Two wild Chinese water deer were referred to the Veterinary Medical Center of Chungbuk National University in South Korea, presumably the result of traffic accidents. Thin blood smears, which were stained with Giemsa, revealed intraerythrocytic parasites; however, the deer had no remarkable findings on physical examination. Polymerase chain reaction and direct sequencing indicated that the parasite was nearly identical to the unidentified Theileria sp. previously found in China. Phylogenetic analysis showed that the Theileria sp. identified in these cases are closest to the group of unidentified Theileria spp. previously found in China and Japan.

Serum adipokine concentrations in dogs with naturally occurring pituitary-dependent hyperadrenocorticism.

Background An excess of intra‐abdominal fat is observed frequently in dogs with hyperadrenocorticism (HAC). Adipokine dysregulation is a possible cause of complications related to visceral obesity, but little information is available on adipokine in dogs with naturally occurring HAC. Objectives To examine the differences in the circulating adipokines concentrations in overweight dogs with and without pituitary‐dependent HAC (PDH). Animals Thirty healthy dogs and 15 client‐owned dogs with PDH. Methods Case–controlled observational study, which enrolled 15 overweight dogs diagnosed with PDH and 30 otherwise healthy dogs of similar body condition score. Nine of 15 dogs with PDH were treated with low‐dose trilostane twice daily and reassessed after treatment. Results The serum leptin (P < .0001) and insulin (P < .0001) concentrations were significantly higher in the PDH group (leptin, 22.8 ± 8.8 [mean ± SD]; insulin, 9.1 ± 6.1) than the healthy group (leptin, 4.9 ± 3.7; insulin, 1.9 ± 0.9). However, there were no significant differences in the adiponectin, resistin, tumor necrosis factor (TNF)‐α, interleukin (IL)‐1β, IL‐6, IL‐10, and IL‐18 levels between the 2 groups. In the PDH group, the serum cortisol concentrations had a linear association with the leptin concentrations, and there were significant decreases in the leptin (P = .0039) and insulin (P = .0039) levels after trilostane treatment. However, the leptin and insulin levels remained higher after trilostane treatment than in healthy control dogs with similar body condition score. Conclusions and Clinical Importance Hypercortisolemia in dogs with PDH might upregulate the circulating leptin levels. However, a large population‐based study will be necessary to determine whether the upregulation of leptin is involved directly with the complications caused by HAC.

Alteration in E-Cadherin/β-Catenin Expression in Canine Melanotic Tumors

β-Catenin, encoded by the ctnnb1 gene, plays a critical role in intercellular adhesion, and its altered expression has been implicated in tumor progression in humans and animals. The aims of this study were to examine the alterations in β-catenin expression in canine melanoma as well as the causes of these changes (eg, E-cadherin or exon 3 mutations) and to compare identified changes between skin and oral melanomas. Forty-two primary canine skin and oral melanoma tissue samples were used in the study. The expression levels of ctnnb1 and the levels of E-cadherin/β-catenin complex in the tissues were determined by semiquantitative RT-PCR and immunohistochemistry, respectively. The mutational status of β-catenin exon 3 was examined by DNA sequencing. RT-PCR revealed higher levels of ctnnb1 expression in oral melanoma tissues compared with normal melanocytes, irrespective of sex or histopathological appearance of the tissue (ie, amelanotic vs melanotic). Immunohistochemistry revealed simultaneous loss of membrane E-cadherin/β-catenin complex and cytoplasmic accumulation of both proteins in 37 cases (84%). Intranuclear β-catenin was also detected in all tissues with reduced membrane β-catenin expression. In mutational analyses, one amelanotic oral melanoma showed 13 single nucleotide polymorphisms (SNPs); however, after protein translation, all the SNPs were silent mutations. The present study demonstrates that dysregulation of E-cadherin/β-catenin complexes is involved in both types of canine melanotic tumors and that the disruption of E-cadherin/β-catenin complexes and increased β-catenin may induce tumor progression and malignancy.

Efficacy of Low- and High-Dose Trilostane Treatment in Dogs (< 5 kg) with Pituitary-Dependent Hyperadrenocorticism

BACKGROUND Trilostane is commonly used to treat pituitary-dependent hyperadrenocorticism (PDH) in dogs. There are differing opinions regarding the dose and frequency of trilostane administration in dogs with PDH. OBJECTIVES To compare the efficacy of 2 trilostane protocols in the treatment of dogs with PDH. ANIMALS Sixteen client-owned dogs with PDH and a body weight <5 kg. METHODS Prospective observational study. Group A (n=9; low-dose treatment group) received 0.78 ± 0.26 mg of trilostane/kg PO every 12 h and group B (n = 7; high-dose treatment group) 30 mg of trilostane/dog PO every 24 h. All of the dogs were reassessed at 2, 4, 8, 12, 16, and 24 weeks after the initiation of treatment. RESULTS An improvement in both ACTH-stimulated serum cortisol concentrations and clinical signs occurred more slowly in group A than in group B; however, after 20 weeks of treatment, 2/7 dog in group B had clinical signs and abnormal laboratory findings consistent with hypoadrenocorticism. At 24 weeks, an improvement in the clinical findings of all of the dogs in both groups was detected. CONCLUSIONS AND CLINICAL IMPORTANCE In dogs with PDH, twice-daily administration of low-dose trilostane is an effective approach to the management of PDH. In addition, our results suggest fewer potential adverse effects if trilostane is administered twice daily in the lower dose.

Asymptomatic Babesia microti-like parasite infection in wild raccoon dogs (Nyctereutes procyonoides) in South Korea

We describe asymptomatic piroplasmosis caused by a Babesia microti–like parasite in wild raccoon dogs (Nyctereutes procyonoides) diagnosed by blood smear and DNA analysis. This is the first description of natural B. microti–like parasite infection in raccoon dogs and suggests that the wild raccoon dog can be a source for B. microti–like parasite infection of domestic dogs and humans.

Dermatitis Caused by Neosartorya hiratsukae Infection in a Hedgehog

ABSTRACT This case report describes the fungal dermatitis caused by Neosartorya hiratsukae infection in a household hedgehog confirmed by microscopic examination of conidiophores and DNA analyses including the internal transcribed spacer region, partial β-tubulin, and the calmodulin gene. It is the first report of a natural N. hiratsukae infection in animals.