• 재무관리연구
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• 제26권4호
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• pp.141-163
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• 2009

Using the extensive datasets, I analyze the effect of tick size changes on the intraday patterns of spread and depth. I show that intraday variations in spread (depth) are greater (smaller) with smaller tick size during the early hour of trading and become smaller (larger) during the last hour of trading. And the standardized spreads (depths) are quoted at the lower (higher) levels as the tick size becomes smaller. I also find that U-shaped intraday spread pattern changes to the reverse flat S-shape while inverted U-shaped depth pattern does to the flat S-shape.

• Parasites, Hosts and Diseases
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• 제27권1호
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• pp.67-69
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• 1989

진드기(Ixodes nipponensisi Ixodidae)에 의한 인체 두피 감염 1례를 확인하였다. 환자는 63세된 여자로 야외 작업 후 이 진드기에 감염되었고, 흡혈이 진행됨에 따라 충체가 점점 커지자 이를 종양으로 생각하고 내원하였다. 내원 당시 환자는 얼굴의 부종, 전신무력감 등을 호소하였으나 교상으로 인한 피부 병소의 출혈과 변색 이외에 특기할 만한 소견은 관찰할 수 없었다. 적출한 충체를 형태학적으로 관찰한 결과 국내에는 보고된 바 없는 I. nipponensis로 동정할 수 있었다. 이 증례는 진드기 (tick)에 의한 인체 감염의 국내 기록 중 제 4례에 해당된다.

• Parasites, Hosts and Diseases
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• 제44권2호
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• pp.157-161
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• 2006

A scalp mass surgically excised from a 4-year-old Korean boy was identified as a tick through histological observations. In sections of the mass, characteristic features of a tick, including its gross contour, cuticular structures, well developed musculature and salivary glands, and the capitulum, were discovered. In particular, the capitulum is anteriorly protruded, which strongly suggests that the specimen be a hard tick of family Ixodidae. However, the pre-sent histological features were not enough to determine the genus and species of the tick, because information on sectional morphologies of different tick species is unavailable. This is a rare case of tick infestation on the scalp diagnosed in histological sections.

• Journal of Veterinary Science
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• 제22권3호
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• pp.37.1-37.14
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• 2021

Background: Ticks are one of the most common external parasites in dogs, and are associated with the transmission of a number of major zoonoses, which result in serious harm to human health and even death. Also, the increasing number of pet dogs and pet owners in China has caused concern regarding human tick-borne illnesses. Accordingly, studies are needed to gain a complete understanding of the bacterial composition and diversity of the ticks that parasitize dogs. Objectives: To date, there have been relatively few reports on the analysis of the bacterial community structure and diversity in ticks that parasitize dogs. The objective of this study was to investigate the microbial composition and diversity of parasitic ticks of dogs, and assessed the effect of tick sex and geographical region on the bacterial composition in two tick genera collected from dogs in China. Methods: A total of 178 whole ticks were subjected to a 16S ribosomal RNA (rRNA) next generation sequencing analysis. The Illumina MiSeq platform targeting the V3-V4 region of the 16S rRNA gene was used to characterize the bacterial communities of the collected ticks. Sequence analysis and taxonomic assignment were performed using QIIME 2 and the GreenGene database, respectively. After clustering the sequences into taxonomic units, the sequences were quality-filtered and rarefied. Results: After pooling 24 tick samples, we identified a total of 2,081 operational taxonomic units, which were assigned to 23 phyla and 328 genera, revealing a diverse bacterial community profile. The high, moderate and low prevalent taxa include 46, 101, and 182 genera, respectively. Among them, dominant taxa include environmental bacterial genera, such as Psychrobacter and Burkholderia. Additionally, some known tick-associated endosymbionts were also detected, including Coxiella, Rickettsia, and Ricketssiella. Also, the potentially pathogenic genera Staphylococcus and Pseudomonas were detected in the tick pools. Moreover, our preliminary study found that the differences in microbial communities are more dependent on the sampling location than tick sex in the tick specimens collected from dogs. Conclusions: The findings of this study support the need for future research on the microbial population present in ticks collected from dogs in China.

• Parasites, Hosts and Diseases
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• 제61권4호
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• pp.439-448
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• 2023

Tick infestation causes a significant threat to human and animal health, requiring effective immunological control methods. This study aimed to investigate the potential of recombinant Haemaphysalis longicornis enolase protein for tick vaccine development. The exact mechanism of the recently identified enolase protein from the H. longicornis Jeju strain remains poorly understood. Enolase plays a crucial role in glycolysis, the metabolic process that converts glucose into energy, and is essential for the motility, adhesion, invasion, growth, and differentiation of ticks. In this study, mice were immunized with recombinant enolase, and polyclonal antibodies were generated. Western blot analysis confirmed the specific recognition of enolase by the antiserum. The effects of immunization on tick feeding and attachment were assessed. Adult ticks attached to the recombinant enolase-immunized mice demonstrated longer attachment time, increased bloodsucking abilities, and lower engorgement weight than the controls. The nymphs and larvae had a reduced attachment rate and low engorgement rate compared to the controls. Mice immunized with recombinant enolase expressed in Escherichia coli displayed 90% efficacy in preventing tick infestation. The glycolytic nature of enolase and its involvement in crucial physiological processes makes it an attractive target for disrupting tick survival and disease transmission. Polyclonal antibodies recognize enolase and significantly reduce attachment rates, tick feeding, and engorgement. Our findings indicate that recombinant enolase may be a valuable vaccine candidate for H. longicornis infection in experimental murine model.

• 대한수의학회지
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• 제54권2호
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• pp.117-120
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• 2014

Chemotherapeutic treatment is still the foundation of tick control programs. This study investigated the acaricidal efficacy of cypermethrin alone and in combination with chlorpyrifos against Haemaphysalis (H.) longicornis. Unfed larval ticks were exposed to 0.1, 1.0, and 10 mg/mL cypermethrin for 60 min, after which the acaricidal efficacy was examined based on tick mortality. All compounds showed similar suppression curves, with the best control being achieved by cypermethrin and chlorpyrifos (1 : 1 ratio) at 10 mg/mL. Effective cypermethrin concentrations for tick control were two to seven times higher than the recommended doses, indicating resistance by H. longicornis.

• Parasites, Hosts and Diseases
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• 제52권6호
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• pp.685-690
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• 2014

A perianal tick and the surrounding skin were surgically excised from a 73-year-old man residing in a southwestern costal area of the Korean Peninsula. Microscopically a deep penetrating lesion was formed beneath the attachment site. Dense and mixed inflammatory cell infiltrations occurred in the dermis and subcutaneous tissues around the feeding lesion. Amorphous eosinophilic cement was abundant in the center of the lesion. The tick had Y-shaped anal groove, long mouthparts, ornate scutum, comma-shaped spiracular plate, distinct eyes, and fastoons. It was morphologically identified as a fully engorged female Amblyomma testudinarium. This is the third human case of Amblyomma tick infection in Korea.

• 한국임상수의학회지
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• 제10권1호
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• pp.101-109
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• 1993

This study was attempted to develop a rearing method of the tick(Haemaphysalis longicornis) at the laboratory in winter. The rearing conditions for ticks in winter were summarized as follows; Even in the winter, under controlled Incubator on 25~3$0^{\circ}C$ and 90~95%, temperature and humidity, respectively, it is possible to rear the ticks normally as on summer. in the usual laboratory room temperature and humidity, 20~$25^{\circ}C$ and 51 ~77%. In the ticks collected in summer, the life span of the ticks, from hatching to death, was 91～129(112.8$\pm$15.2) days in the lagoratory, and the number of the oviposited eggs from a tick were about 1,680~2,460 and the hatching rate of the oviposited eggs was about 95(92~98)%. The life span of the ticks which were reared in the laboratory in winter was 89-138(112.2$\pm$21.1) days, and the number of the oviposited eggs from the tick were about 1,382~2,674 and the hatching rate of them was about 89.5(87~92)%. In the rearing of the tick at the laboratory, the dogs, rabbits and mice were able to use the hosts for the tick. The proper temperature to feed the ticks on the cattle in the cold season was obtained by $Hokalong^{\circledR}$ which were attached on the out side of sac which covered bovine ear where attached ticks.

• Parasites, Hosts and Diseases
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• 제56권3호
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• pp.305-308
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• 2018

This study was aimed to disclose the prevalence rate of tick-borne pathogens from ticks collected from cattle and wild animals in Tanzania in 2012. Ticks were collected from slaughtered cattle and dead wild animals from November 5 to December 23, 2012 and identified. PCR for detecting Anaplasmataceae, Piroplamidae, Rickettsiaceae, Borrelia spp., and Coxiella spp. were done. Among those tested, Rickettsiaceae, Piroplasmidae, and Anaplasmataceae, were detected in ticks from the 2 regions. Rickettsiaceae represented the major tick-borne pathogens of the 2 regions. Ticks from animals in Maswa were associated with a higher pathogen detection rate compared to that in ticks from Iringa. In addition, a higher pathogen detection rate was observed in ticks infesting cattle than in ticks infesting wild animals. All examined ticks of the genus Amblyomma were infected with diverse pathogens. Ticks of the genera Rhipicephalus and Hyalomma were infected with 1 or 2 pathogens. Collectively, this study provides important information regarding differences in pathogen status among various regions, hosts, and tick species in Tanzania. Results in this study will affect the programs to prevent tick-borne diseases (TBD) of humans and livestock in Tanzania.

• Journal of Ecology and Environment
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• 제43권4호
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• pp.427-437
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• 2019

Background: Climate change is believed to be continuously affecting ticks by influencing their habitat suitability. However, we attempted to model the climate change-induced impacts on future genus Rhipicephalus distribution considering the major environmental factors that would influence the tick. Therefore, 50 tick occuance points were taken to model the potential distribution using maximum entropy (MaxEnt) software and 19 climatic variables, taking into account the ability for future climatic change under representative concentration pathways (RCPs) 4.5 and 8.5, were used. Results: MaxEnt model performance was tested and found with the AUC value of 0.99 which indicates excellent goodness-of-fit and predictive accuracy. Current models predict increased temperatures, both in the mid and end terms together with possible changes of other climatic factors like precipitation which may lead to higher tick-borne disease risks associated with expansion of the range of the targeted tick distribution. Distribution maps were constructed for the current, 2050, and 2070 for the two greenhouse gas scenarios and the most dramatic scenario; RCP 8.5 produced the highest increase probable distribution range. Conclusions: The future potential distribution of the genus Rhipicephalus show potential expansion to the new areas due to the future climatic suitability increase. These results indicate that the genus population of the targeted tick could emerge in areas in which they are currently lacking; increased incidence of tick-borne diseases poses further risk which can affect cattle production and productivity, thereby affecting the livelihood of smallholding farmers. Therefore, it is recommended to implement climate change adaptation practices to minimize the impacts.