• Parasites, Hosts and Diseases
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• 제56권1호
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• pp.53-59
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• 2018

Tick saliva is critically important for continuous attachment to the host, blood feeding for days, and transmission of tick-borne pathogens. To characterize the patterns of inflammatory cytokine gene expression during its attachment and blood sucking time, peripheral blood samples of rabbits infested with Haemaphysalis longicornis ticks were collected at different intervals. Blood histamine concentration was evaluated as well as gene encoding IFN-${\gamma}$, TNF-${\alpha}$, IL-2, IL-6, IL-4, and IL-10 were compared with non-infested rabbits. Blood histamine concentration of tick-infested rabbits during fast feeding time was significantly higher than that of non-infested rabbits. In both nymph and adult tick infested rabbits, expression of TNF-${\alpha}$ and IFN-${\gamma}$ genes were decreased significantly (P<0.05), while expression of IL-4, IL-6, and IL-10 were increased 1.3 to 7 folds in adult infested rabbits with the exception of IL-6 that was significantly (P<0.05) decreased in nymph infested rabbits. IL-2 was not expressed in either nymph or adult infestation. H. longicornis saliva is capable of modulate host responses through a complex correlation with histamine and Th1, Th2 mediated cytokines that suppress the inflammatory responses directed toward inflammatory mediators introduced into the host during tick feeding.

• 한국안광학회지
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• 제7권2호
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• pp.223-228
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• 2002

기생충의 감염에 의하여 기생충증(parasitosis)이 유발하게되며 특히 안질환을 유발할 수 있는 기생충에는 원충류(Protozoa), 선충류(Nematodes), 조충류(Cestodes) 등이 있으며 이들 기생충들은 기생충과 매개체(Vector), 기생충과 숙주(Host), 숙주(Host)와 숙주(Host)의 연결고리가 있으며 이들의 관계가 오염이 되었거나 환경이 불량하여 숙주(Host)인 사람에게 기생하게되면 기생충의 독성, 숙주(Host)의 저항성 등에 따라 조직의 파괴나 염증, 알레르기 반응 등을 일으켜 질환을 일으키며 심하면 실명까지 유발케 한다. 이를 예방하려면 깨끗한 환경과 청결을 생활하여야 한다.

• Journal of Veterinary Science
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• 제23권2호
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• pp.28.1-28.18
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• 2022

Enteropathogenic Escherichia coli (EPEC) is a major cause of infantile diarrhea in developing countries. However, sporadic outbreaks caused by this microorganism in developed countries are frequently reported recently. As an important zoonotic pathogen, EPEC is being monitored annually in several countries. Hallmark of EPEC infection is formation of attaching and effacing (A/E) lesions on the small intestine. To establish A/E lesions during a gastrointestinal tract (GIT) infeciton, EPEC must thrive in diverse GIT environments. A variety of stress responses by EPEC have been reported. These responses play significant roles in helping E. coli pass through GIT environments and establishing E. coli infection. Stringent response is one of those responses. It is mediated by guanosine tetraphosphate. Interestingly, previous studies have demonstrated that stringent response is a universal virulence regulatory mechanism present in many bacterial pathogens including EPEC. However, biological signficance of a bacterial stringent response in both EPEC and its interaction with the host during a GIT infection is unclear. It needs to be elucidated to broaden our insight to EPEC pathogenesis. In this review, diverse responses, including stringent response, of EPEC during a GIT infection are discussed to provide a new insight into EPEC pathophysiology in the GIT.

• IMMUNE NETWORK
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• 제20권5호
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• pp.37.1-37.15
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• 2020

Mycobacterium tuberculosis (Mtb) is an etiologic pathogen of human tuberculosis (TB), a serious infectious disease with high morbidity and mortality. In addition, the threat of drug resistance in anti-TB therapy is of global concern. Despite this, it remains urgent to research for understanding the molecular nature of dynamic interactions between host and pathogens during TB infection. While Mtb evasion from phagolysosomal acidification is a well-known virulence mechanism, the molecular events to promote intracellular parasitism remains elusive. To combat intracellular Mtb infection, several defensive processes, including autophagy and apoptosis, are activated. In addition, Mtb-ingested phagocytes trigger inflammation, and undergo necrotic cell death, potentially harmful responses in case of uncontrolled pathological condition. In this review, we focus on Mtb evasion from phagosomal acidification, and Mtb interaction with host autophagy, apoptosis, and necrosis. Elucidation of the molecular dialogue will shed light on Mtb pathogenesis, host defense, and development of new paradigms of therapeutics.

• IMMUNE NETWORK
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• 제4권2호
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• pp.73-80
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• 2004

Viruses are obligate intracellular parasites which cause infection by invading and replicating within cells. The immune system has mechanisms which can attack the virus in extracellular and intracellular phase of life cycle, and which involve both non-specific and specific effectors. The survival of viruses depends on the survival of their hosts, and therefore the immune system and viruses have evolved together. Immune responses to viral infection may be variable depending on the site of infection, the mechanism of cell-to-cell spread of virus, physiology of the host, host genetic variation, and environmental condition. Viral infection of cells directly stimulates the production of interferons and they induce antiviral state in the surrounding cells. Complement system is also involved in the elimination of viruses and establishes the first line of defence with other non-specific immunity. During the course of viral infection, antibody is most effective at an early stage, especially before the virus enters its target cells. The virus- specific cytotoxic T lymphocytes are the principal effector cells in clearing established viral infections. But many viruses have resistant mechanism to host immune responses in every step of viral infection to cells. Some viruses have immune evasion mechanism and establish latency or persistency indefinitely. Furthermore antibodies to some viruses can enhance the disease by the second infection. Immune responses to viral infection are very different from those to bacterial infection.

• 아태비즈니스연구
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• 제15권2호
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• pp.237-256
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• 2024

Purpose - The purpose of this study was to analyze the interrelationship between the characteristics of TikTok live commerce: host expertise, host reliability, sales marketing strategy, product price, logistics speed, refund convenience), purchase intention, and continuous purchase intention. Design/methodology/approach - This study collected 470 questionnaires collected from the survey for consumers using TikTok live commerce in China and conducted an empirical analysis using SPSS 24.0 statistical packages for 423 valid questionnaires (90%) excluding unfaithful responses. Findings - First, it was confirmed that the characteristics of TikTok Live (host expertise, host reliability, sales marketing strategy, product price, logistics speed, and refund convenience) had a positive effect on consumers' purchase intention. Second, it was confirmed that the higher the consumer's purchase intention, the higher the continuous purchase intention. Third, it was also confirmed that the characteristics of TikTok Live (host expertise, host reliability, sales marketing strategy, product price, logistics speed, and refund convenience) had a positive effect on consumers' continuous purchase intention. Research implications or Originality - Through the research results of this paper, product prices have the greatest influence on consumers' purchase intentions, followed by sales marketing strategies and host expertise. Therefore, this study aims to present implications for product prices, sales marketing strategies, and host expertise in TikTok live commerce based on empirical analysis and analysis of previous studies.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2006년도 제23차 정기총회 및 학술발표회
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• pp.7-16
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• 2006

Poultry products including meat and eggs constitute a major protein source in the American diet and disease - causing pathogens represent major challenges to the poultry industry. More than 95 % of pathogens enter the host through the mucosal surfaces of the respiratory, digestive and reproductive tracts and over the past few decades, the two main mechanisms used to control diseases have been the use of vaccines and antibiotics. However, in the poultry industry, there are mounting concerns over the ability of current vaccines to adequately protect against emerging hyper - virulent strains of pathogens and a lack of suitable, cost effective adjuvants. Thorough investigation of the immunogenetic responses involved in host-pathogen interactions will lead to the development of new and effective strategies for improving poultry health, food safety and the economic viability of the US poultry industry. In this paper, I describe the development of immunogenomic and proteomic tools to fundamentally determine and characterize the immunological mechanisms of the avian host to economically significant mucosal pathogens such as Eimeria. Recent completion of poultry genome sequencing and the development of several tissue-specific cDNA libraries in chickens are facilitating the rapid application of functional immunogenomics in the poultry disease research. Furthermore, research involving functional genomics, immunology and bioinformatics is providing novel insights into the processes of disease and immunity to microbial pathogens at mucosal surfaces. In this presentation, a new strategy of global gene expression using avian macrophage (AMM) to characterize the multiple pathways related to the variable immune responses of the host to Eimeria is described. This functional immunogenomics approach will increase current understanding of how mucosal immunity to infectious agents operates, and how it may be enhanced to enable the rational development of new and effective strategies against coccidiosis and other mucosal pathogens.

• IMMUNE NETWORK
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• 제3권4호
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• pp.261-267
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• 2003

The periodontal diseases are infections caused by bacteria in oral biofilm, a gelatinous mat commonly called dental plaque, which is a complex microbial community that forms and adhere to tooth surfaces. Host immune-pathogen interaction in periodontal disease appears to be a complex process, which is regulated not only by the acquired immunity to deal with ever-growing and -invading microorganisms in periodontal pockets, but also by genetic and/or environmental factors. However, our understanding of the pathogenesis in human periodontal diseases is limited by the lack of specific and sensitive tools or models to study the complex microbial challenges and their interactions with the host's immune system. Recent advances in cellular and molecular biology research have demonstrated the importance of the acquired immune system in fighting the virulent periodontal pathogens and in protecting the host from developing further devastating conditions in periodontal infections. The use of genetic knockout and immunodeficient mouse strains has shown that the acquired immune response, in particular, $CD4^+$ T-cells plays a pivotal role in controlling the ongoing infection, the immune/inflammatory responses, and the subsequent host's tissue destruction.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.197-201
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• 2008

Conformational heterogeneity of directly linked multiporphyrin arrays with larger molecular length retards their utilities in practical applications such as two-photon absorption and molecular photonic wire. In this regard, here we adopted a way to overcome the conformational heterogeneity through hydrogen bonding by selective binding of meso aryl substituents of porphyrins (host) with urea (guest) to form helical structure. Using steady-state and time-resolved spectroscopy, we observed the enhanced fluorescence quantum yield by ~1.8 to 2.4 times, enhanced anisotropy values and the disappearance of fast fluorescence decay component in the host-guest helical forms. In addition, the enhanced nonlinear optical responses of helical arrays infer the extended inter-porphyrin electronic coupling due to a significant change in dihedral angle between the neighboring porphyrin moieties. The current host-guest strategy will provide a guideline to improve the structural homogeneity of the photonic wire.

• Asian-Australasian Journal of Animal Sciences
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• 제15권6호
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• pp.912-924
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• 2002

Disease susceptibility is linked to nutritional status for a wide range of human and animal diseases. Nutritional status can influence both resistance (ability to resist the pathogen) and resilience (ability to tolerate or ameliorate the effects of the pathogen). This review focuses on the nutritional modulation of gastro-intestinal nematode infection in domestic ruminants, primarily sheep. It highlights the duality of the adverse consequences of infection on host nutritional status and the adverse consequences of poor host nutritional status on resistance to infection. Central to both phenomena is the complex, gut-based immune response to gastrointestinal nematode infection. The potential for strategic nutritional supplementation to enhance host resistance and resilience is reviewed together with recent findings on responses to increased ME supply, and long term effects on host immunity of short term protein supplementation.