• Title/Summary/Keyword: host-parasites

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Ophthalmic diseases caused by parasitic infections and its prevention (기생충 감염에 의한 안질환과 예방)

  • Joo, Kyung Bok;Roh, Pyong Ui
    • Journal of Korean Ophthalmic Optics Society
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    • v.7 no.2
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    • pp.223-228
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    • 2002
  • The infection of parasites causes all kinds of parasitosis. The parasites that causes ophthalmic diseases are Protozoa, Nematodes, Cestodes and so on. These parasites has specific connection chains in between parasite and vector, parasite and host, host and host. If these connection chains were polluted or exposed into the worsened environments, the parasite are infected into human body which is its host. The parasite causes the destroy of organic tissues or inflammation and allergic responses by its toxicity and resistance of the host. In worst case, it might cause blindness. In order to prevent these disease, we should keep the clean and clear living environment of every human being.

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What's in a name? Monophyly of genera in the red algae: Rhodophyllis parasitica sp. nov. (Gigartinales, Rhodophyta); a new red algal parasite from New Zealand

  • Preuss, Maren;Zuccarello, Giuseppe C.
    • ALGAE
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    • v.29 no.4
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    • pp.279-288
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    • 2014
  • Red algal parasites are common within red algae and are mostly closely related to their hosts, but have a reduced habit. In the past, red algal parasites, due to their reduced morphology, have been given distinct generic names, even though they are often phylogenetically nested in their host's genus. This is a problem nomenclaturally for maintenance of a taxonomy based on monophyly. This study investigates the morphology, genetic variation and distribution of an undescribed red algal parasite growing on its host Rhodophyllis membranacea, widely distributed throughout New Zealand. Microscopy, molecular markers (plastid, mitochondrial, nuclear), and herbarium investigation were used to investigate this species. The parasite is widely distributed throughout New Zealand. All molecular markers clearly show that the parasite is almost identical to the host, even though morphologically quite distinct from members of the host genus. We believe that to maintain monophyly of Rhodophyllis the parasite should be described as a new species of Rhodophyllis, Rhodophyllis parasitica sp. nov. We also recommend that in order to maintain generic monophyly most red algal parasite genera should also be transferred to their host genus.

A comparative study of ectoparasites occurrence between grass carp and silver carp in guilan province culture ponds, Iran

  • Asgharnia, Mehrdad;Ghasemi, Mohaddes
    • Journal of fish pathology
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    • v.34 no.2
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    • pp.169-176
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    • 2021
  • Parasitic infection is among the most common problems for carp cultivation. They are also important for the principal entrance of other hazardous infections as well. This study was carried out for determining of parasitic fauna of two major carp known as silver and grass carp with the comparison of prevalence value and intensity rate of parasites among them, alongside the relationship between the biometric characteristics and host sex with the infection level. For this purpose, a total of 94 fish samples were caught randomly using a fishing net, from Guilan ponds during spring and summer of the year 2018 and transported alive to the laboratory. Upon arriving, the biometric characteristics and genus of each carp were measured individually. Specimens were then acquired from the skin, gills, and eyes of the carp and examined according to standard parasitology methods. Recovered parasites were observed under a light microscope and then fixed for identification. As the result, the occurrence and intensity in the higher length group were comparatively greater than the lower one. Also, the prevalence and intensity of total parasites in male carp were higher than in females. In this research, Dactylogyrus hypophthalmichthys and Dactylogyrus aristhichtys were observed in silver carp and Dactylogyrus lamellatus was detected in grass carp. In the paper below, we found that the host specificity varies in different species of Dactylogyrus isolated from grass carp and silver carp.

Infection Example of Parasites of the Common squid, Todarodes pacificus (동해산 오징어, Todarodes pacificus 기생충 감염 예)

  • KIM Yeong Hye;KANG Yong Joo;PARK Joo Seok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.4
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    • pp.534-536
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    • 1999
  • The common squid, Todarodes pacificus was infected by parasites. The parasites may be infective to humans if common squid are eaten raw as 'sashimi' or 'sushi'. The species of the parasites in host, T. pacificus were Tentacularia sp., Orygmatobothrim sp. and Ponocaecum sp.. The prevalence, relative density and mean intensity of three parasites were $100.00\%$, 24.13 and 24.13 respectively.

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Biological Control of Pests of Non-Mulberry Silkworms and Its Host Plants in India

  • Singh, R.N.;Maheshwari, M.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.4 no.2
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    • pp.83-91
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    • 2002
  • The protection of silkworm and its host plants from various kinds of pests parasite and predator is a chronic problem in sericulture. Silkworms and its primary food plants are heavily damaged by large number of pest. The major pests of primary tasar food plants (Terminalia arjuna and Terminalia tomentosa) are the gall insect (Trioza fletcheri minor). Various species of aphids (Eutrichosiphum sp.) have been recorded to damage oak tasar food plants whereas muga silkworm host plants (Machilus bombycina and Litsaea polyantha) are generally attacked by stem bores (Zeuzera multistrigata). Castor (Ricinus communis) is one of the primary host plant of eri silkworm and extensive damage is caused by the castor white fly (Trialeurodes ricini). Insects pests are major enemies of silkworms. Parasites (Blepharipa zebina, Exorista bombycis, Apateles glomeratus), predators (Canthecona furcellata, Sycanus collaris, Hierodulla bipapilla), wasps (Vespa orientalix) and ants (Oecophylla smargdina) continues to cause damage to silk industry. It is estimated that the losses due to parasites and predators are to an extent of 15-20 percent and varies from crop to crop. The complexities in the behaviour and life cycle of pest population existing in semi ecosystem warrant a special attention for their effective management specially in changing scenario for our modern sericulture. Though use of synthetic insecticides has provided us with effective control of almost all major pests and predators, yet their undesirable side effects limit their continued use. Biological control is one of the most important method which can be used to control the pests, parasites and predators population in sericulture. Various potential parasitoids, which can be utilized as an agent of biological control in sericulture have been screened. The natural enemies of the uzi fly (E. bombycis and B. zebina ) are already present in the nature. Nesolynx thymus, Trichria sp., Splangia endius, Dirhinus sp., Trichopria sp., Trichomalopsis apanteloctena and Pediobius sp. are the major parasitoids effective against uzi fly pupa. The scelionid Psix striaticeps and Trissolcus sp. are the Potential egg Parasitoids against stink bug (Canthecona furcellata). Various other native natural potential parasitoids have been screened and suitable strategies have been developed to check the population of pest insect in sericulture.

Avian Gut Immune System and Local Responses to Eimerial Parasites (조류의 장내 면역체계와 콕시듐(Eimeria)기생충들에 대한 국소면역 반응)

  • Lillehoj, H.S.
    • Korean Journal of Poultry Science
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    • v.26 no.2
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    • pp.131-144
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    • 1999
  • Coccidiosis, an intestinal infection caused by intracellular protozoan parasites belonging to several different species of Eimeria seriously impairs the growth and feed utilization of livestock and poultry. Due to complex life cycle of organism and intricate host immune responses to Elmeria, coccidia vaccine development has been difficult. Understanding of basic imunobiology of pertinent host-parasite interactions is necessary for the development of novel control strategy. Although chickens infected with Eimeria spp. produce parasite-specific antibodies in both the circulation and mucosal secretions, antibody mediated responses play a minor role in protection gainst coccidiosis. Rather, increasing evidence show that cell-mediated immunity plays a major role in resistance to coccidiosis. T-lymphocytes appear to respond to coccidiosis both through cytokine production and a direct cytotoxic attack on infected cells. The exact mechanisms by which T-cells eliminate the parasites, however, remain to be investigated. Since it is crucial to understand the intestinal immune system in order to develop an immunological control strategy against any intestinal immune system in order to develop an immunological control strategy against any intestinal diseases, this presentation will summarize our current understanding of the avian intestinal immune system and mucosal immune responses to Eimeria, to provide a conceptual overview of the complex molecular and cellular events involved in intestinal immune responses to enteric pathogens.

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Leishmania Vaccines: the Current Situation with Its Promising Aspect for the Future

  • Rasit Dinc
    • Parasites, Hosts and Diseases
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    • v.60 no.6
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    • pp.379-391
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    • 2022
  • Leishmaniasis is a serious parasitic disease caused by Leishmania spp. transmitted through sandfly bites. This disease is a major public health concern worldwide. It can occur in 3 different clinical forms: cutaneous, mucocutaneous, and visceral leishmaniasis (CL, MCL, and VL, respectively), caused by different Leishmania spp. Currently, licensed vaccines are unavailable for the treatment of human leishmaniasis. The treatment and prevention of this disease rely mainly on chemotherapeutics, which are highly toxic and have an increasing resistance problem. The development of a safe, effective, and affordable vaccine for all forms of vector-borne disease is urgently needed to block transmission of the parasite between the host and vector. Immunological mechanisms in the pathogenesis of leishmaniasis are complex. IL-12-driven Th1-type immune response plays a crucial role in host protection. The essential purpose of vaccination is to establish a protective immune response. To date, numerous vaccine studies have been conducted using live/attenuated/killed parasites, fractionated parasites, subunits, recombinant or DNA technology, delivery systems, and chimeric peptides. Most of these studies were limited to animals. In addition, standardization has not been achieved in these studies due to the differences in the virulence dynamics of the Leishmania spp. and the feasibility of the adjuvants. More studies are needed to develop a safe and effective vaccine, which is the most promising approach against Leishmania infection.

Respiratory Syncytial Virus (RSV) Modulation at the Virus-Host Interface Affects Immune Outcome and Disease Pathogenesis

  • Tripp, Ralph A.
    • IMMUNE NETWORK
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    • v.13 no.5
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    • pp.163-167
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    • 2013
  • The dynamics of the virus-host interface in the response to respiratory virus infection is not well-understood; however, it is at this juncture that host immunity to infection evolves. Respiratory viruses have been shown to modulate the host response to gain a replication advantage through a variety of mechanisms. Viruses are parasites and must co-opt host genes for replication, and must interface with host cellular machinery to achieve an optimal balance between viral and cellular gene expression. Host cells have numerous strategies to resist infection, replication and virus spread, and only recently are we beginning to understand the network and pathways affected. The following is a short review article covering some of the studies associated with the Tripp laboratory that have addressed how respiratory syncytial virus (RSV) operates at the virus-host interface to affects immune outcome and disease pathogenesis.

Glutathione Reductase and Thioredoxin Reductase: Novel Antioxidant Enzymes from Plasmodium berghei

  • Kapoor, Gaurav;Banyal, Harjeet Singh
    • Parasites, Hosts and Diseases
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    • v.47 no.4
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    • pp.421-424
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    • 2009
  • Malaria parasites adapt to the oxidative stress during their erythrocytic stages with the help of vital thioredoxin redox system and glutathione redox system. Glutathione reductase and thioredoxin reductase are important enzymes of these redox systems that help parasites to maintain an adequate intracellular redox environment. In the present study, activities of glutathione reductase and thioredoxin reductase were investigated in normal and Plasmodium berghei-infected mice red blood cells and their fractions. Activities of glutathione reductase and thioredoxin reductase in P. berghei-infected host erythrocytes were found to be higher than those in normal host cells. These enzymes were mainly confined to the cytosolic part of cell-free P. berghei. Full characterization and understanding of these enzymes may promise advances in chemotherapy of malaria.

Anti-apoptosis effects by Eimeria tenella infection in Madin-Darby bovine kidney cells

  • Lee, Hyun-A;Hong, Sun-Hwa;Chung, Yung-Ho;Kim, Ok-Jin
    • Korean Journal of Veterinary Service
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    • v.35 no.2
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    • pp.105-109
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    • 2012
  • Apoptosis is a host defense mechanism that the cell uses to limit production of infectious pathogens. Although many bacteria, viruses and parasites can induce apoptosis in infected cells, some pathogens usually exhibit the ability to suppress the induction of apoptosis in the infected cells. Sophisticated evasion strategies of obligate intracellular parasites, in particular prevention of host cell apoptosis, are necessary to ensure successful replication. To study the ability of Eimeria tenella in this regard, in vitro experiments were performed applying Madin-Darby bovine kidney (MDBK) cells as host cell. We have demonstrated that productive infection of adherent cell lines by E. tenella resulted in an anti-apototic effect. This phenomenon was confirmed using in situ terminal deoxynucleotidyl transferase-mediated (TdT) deoxyuridine triphosphates (dUTP)-fluorescein nick end labeling (TUNEL) assay to detect apoptosis. Therefore, E. tenella could complete its cycle of productive infection while inducing anti-apoptosis in the infected cells. This finding might have implications for the pathobiology of E. tenella and other Eimeria species.