• Parasites, Hosts and Diseases
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• v.51 no.6
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• pp.645-650
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• 2013

A simple, rapid, and high-throughput method for detection and identification of Wuchereria bancrofti, Brugia malayi, Brugia pahangi, and Dirofilaria immitis in mosquito vectors and blood samples was developed using a real-time PCR combined with high-resolution melting (HRM) analysis. Amplicons of the 4 filarial species were generated from 5S rRNA and spliced leader sequences by the real-time PCR and their melting temperatures were determined by the HRM method. Melting of amplicons from W. bancrofti, B. malayi, D. immitis, and B. pahangi peaked at $81.5{\pm}0.2^{\circ}C$, $79.0{\pm}0.3^{\circ}C$, $76.8{\pm}0.1^{\circ}C$, and $79.9{\pm}0.1^{\circ}C$, respectively. This assay is relatively cheap since it does not require synthesis of hybridization probes. Its sensitivity and specificity were 100%. It is a rapid and technically simple approach, and an important tool for population surveys as well as molecular xenomonitoring of parasites in vectors.

• Parasites, Hosts and Diseases
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• v.55 no.6
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• pp.673-677
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• 2017

The present study was performed to investigate the seroprevalence and risk factors for Dirofilaria immitis infection in cats from Liaoning province, northeastern China. From October 2014 to September 2016, sera of 651 cats, including 364 domestic cats and 287 feral cats (332 females and 319 males) were assessed. They were tested for the presence of D. immitis antigen using SNAP Heartworm RT test kit. In this population, the average prevalence was 4.5%. Age and rearing conditions (feral or domestic) were found to be associated with the prevalence of D. immitis. The prevalence was significantly higher in feral cats compared with domestic cats (8.4% vs 1.4%, P<0.01). There was no significant difference between males and females (4.7% vs 4.2%, P>0.05), but older cats (${\geq}3$ years old) showed a statistically higher prevalence compared with younger cats (<3 years old) in feral populations (16.8 vs 2.4%, P<0.01), while the difference between the age groups was not statistically significant in domestic cats (2.4% vs 0.51%, P>0.05), all these results suggest that outdoor exposure time may be one of the most important factors for D. immitis prevalence in cats. Results reveal that D. immitis are prevalence in domestic and feral cats in northeastern China, which indicates that appropriate preventive measures should be taken to decrease the incidence of feline heartworm disease in Liaoning province, northeastern China.

• Journal of Veterinary Clinics
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• v.27 no.6
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• pp.631-634
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• 2010

This study was conducted to survey Dirofilaria (D.) immitis antigen, and Anaplasma (A.) phagocytophilum, Borrelia (B.) burgdorferi, and Ehrlichia (E.) canis antibodies among clinically healthy dogs in the Daejeon city and Kangwon province. Whole blood samples were collected from two hundred and fifty two dogs (127 females and 125 males, 147 outdoors and 105 indoors), and they were tested by using ELISA kit (SNAP 4Dx, IDEXX Laboratories, USA). Chi-squared analysis showed that A. phagocytophilum of female dogs in outdoors group was significantly higher prevalence than that of female dogs in indoors group (p < 0.05). In addition, infection rate of A. phagocytophilum of over 7 year-old-dogs in outdoors group revealed significantly higher prevalence than that of indoors group (p < 0.01). In E. canis, the under 4 year-old-dogs (p < 0.05), 4~7 year-old-dogs (p < 0.05) and over 7 year-old-dogs (p < 0.01) in outdoor group showed significantly higher prevalence than that of indoors group, respectively. In conclusion, this study is the large scale survey of canine D. immitis antigen, A. phagocytophilum, B. burgdorferi, and E. canis antibodies in the Daejeon city and Kangwon province, and it provides an useful reference for clinicians.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.21-26
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• 2014

Dirofilaria immitis (heartworm) infections affect domestic dogs, cats, and various wild mammals with increasing incidence in temperate and tropical areas. More sensitive antibody detection methodologies are required to diagnose asymptomatic dirofilariasis with low worm burdens. Applying current transcriptomic technologies would be useful to discover potential diagnostic markers for D. immitis infection. A filarial homologue of the mammalian translationally controlled tumor protein (TCTP) was initially identified by screening the assembled transcriptome of D. immitis (DiTCTP). A BLAST analysis suggested that the DiTCTP gene shared the highest similarity with TCTP from Loa loa at protein level (97%). A histidine-tagged recombinant DiTCTP protein (rDiTCTP) of 40 kDa expressed in Escherichia coli BL21 (DE3) showed immunoreactivity with serum from a dog experimentally infected with heartworms. Localization studies illustrated the ubiquitous presence of rDiTCTP protein in the lateral hypodermal chords, dorsal hypodermal chord, muscle, intestine, and uterus in female adult worms. Further studies on D. immitis-derived TCTP are warranted to assess whether this filarial protein could be used for a diagnostic purpose.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.2
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• pp.88-93
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• 2016

Dirofilaria immitis is a filarial nematode parasite that causes cardiopulmonary dirofilariasis in dogs. The purpose of this study was the development of real-time PCR assays for efficient detection of D. immitis. The D. immitis-specific primers confirmed in our previous study and a newly designed TaqMan probe were used for quantitative diagnostics. First, SYBR Green real-time PCR was performed using the specific primers and serially diluted genomic DNA or plasmid DNA, and melting curve analyses were performed after amplification. The melting curve showed one specific peak in each of the genomic and plasmid DNA reactions, suggesting that the primers specifically amplify the D. immitis cytochrome c oxidase subunit I gene. Comparison of SYBR Green and TaqMan real-time PCR using serially diluted plasmid DNA showed higher efficiency and specificity with TaqMan real-time PCR. The real-time PCR assays developed in this study will provide improved diagnostic methods to overcome the limitations of conventional diagnostic tools and facilitate more rapid and accurate diagnoses.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2008.10a
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• pp.147-147
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• 2008

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2008.10a
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• pp.148-148
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• 2008

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.10a
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• pp.626-626
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• 2007

• Korean Journal of Veterinary Service
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• v.26 no.1
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• pp.19-26
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• 2003

This study was attempted to survey on the prevalence of canine heartworm(Dirofilaria immitis) infection among 100 dogs(male 39, female 61) on the nine breeding farms in eastern Chungnam province in December 2002. Blood samples taken from dogs were examined for the presence of D immitis microfilaria by the modified Knott's test and an antigen test was using FASTest$\^$/ HW Antigne kit (Mega Cor A-6912 Horbranz-Austraia). 1. Eleven(11.0%) of the 100 examined dogs were microfilaria positive, while nineteen dogs(19.0%) were antigen positive, which suggested that the antigen test was more sensitive than the microfilarial test in detecting heartworm infection. 2. Infected dogs were observed higher more at 2 years older ages(4/48, 8.3%) and male(9/39, 23.1%) than young ages(4/48, 8.3%) and female(10/61, 16.4%). 3. The regional infection rates were of Gongju(15/43, 34.9%), Geumsan(4.27, 14.8%), while none of infection dogs in Yeongi(0/30, 0%). 4. Survey for hematological values of D immitis infected dogs : WBC and eosinophils were 21.4${\pm}$7.2 k/${\mu}\ell$, 3.5${\pm}$0.4 k/${\mu}\ell$, respectively. In conculsion, this study could be overemphasized the importance of control program the heartworm in eastern Chungnam province

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.507-516
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• 2003

This study was performed to clarify the induction possibility of anaphylactoid reactions by the administration with the heartworm extracts, and, if any, to elucidate different virulences in terms of the protein concentrdtions and sexes of Dirofilaria immitis. Twenty three clinically healthy D. immitis-free adult dogs were used in the present study. The experimental animals were divided into 5 groups. Group A (5 heads) was administered with an female heartworm extract containing 0.1 g/dl protein concentration. Group B (4 heads) was administered with an male heartworm extract containing 0.1g/dl protein concentration. Group C (5 heads) was administered with an female heartworm extract containing 0.2 g/dl protein concentration. Group D (4 heads) was administered with an male heartworm extract containing 0.2 g/dl protein concentration. Group E (5 heads) was administered with an female heartworm extract containing 0.4 g/dl protein concentration. The changes of clinical symptoms and vital signs (body temperature, heart rate and respiration rate) were examined before and 5 minutes, 15 minutes, 30 minutes, 1 hour, 2 hours and 24 hours after injection with the extracts, respectively. In addition, the changes of hematological values (RBC, PCV and total leukocytes counts), serum chemical values (ALP and CK) were determined. It was considered that heartworm extract could induce anaphylactoid reaction and adult female heartworm extract was more affective than those of adult male heartworm extract in the changes of clinical symptoms, vital signs, hematological values and serum chemical values.