약품미생물학 생명산업과학대학 생물환경학과 김정호

 Protozoa (Protist) Unicellular & Heterotrophic Eukaryotic organisms Non-photosynthetic Mostly motile Traditional classification : means of locomotion Amoeboids 근족충류 Rhizopoda Entamoeba histolytica Sporozoans 포자충류 Sporozoa Plasmodium knowlesi Flagellates 편모충류 Mastigophora Giardia lamblia Ciliates 선모충류 Ciliata Balantidium coli Protozoan Cytoplasm : ectoplasm & endoplasm Ectoplasm ( 외질 ) : hyaline outer layer that is protective in function and also gives rise to the locomotive organ, such as pseudopodium, flagella and cilia. Endoplasm ( 내질 ) : inner portion where there are various organelles and food vacuoles. It manages the metabolism. Protozoa ( 원생동물, 원충류 )

Most protozoa are restricted to moist environments Many form resting cysts which enable them to survive Trophozoite ( 영양체 ) Living stage of protozoa when they can move, take food and reproduce Usually the pathogenic stage Cyst ( 포낭 ) Resting stage of a protozoa with a protective wall Usually the infective stage (transmission) Encystation : Trophozoite → Cyst Excystation : Cyst → Trophozoite Protozoa ( 원생동물, 원충류 )

 Amoebic dysentery (Amoebiasis) : Entamoeba histolytica  Acanthamoeba keratitis : Acanthamoeba  Malaria : Plasmodium vivax, P. malariae, P. falciparum, P. ovale  Trichomoniasis : Trichomonas vaginitis  Toxoplasmosis : Toxoplasma gondii  Giardiasis : Giardia lamblia  Cryptosporidiosis (crypto) : Cryptosporidium  Chagas disease : Trypanosoma cruzi  Leishmaniasis : Leishmania donovani, L. tropica, L. briziliensis  Sleeping Sickness : Trypanosoma gambiense, T. rhodesiense  Primary Amoebic Meningoencephalitis (PAM, or PAME) amoeboid excavate Naegleria fowleri Human parasites

 Amoebiasis Entamoeba histolytica Spread by forming infective cysts Trophozoites are the agent responsible for symptoms Transmitted through contaminated food and water Gastrointestinal infection mild diarrhea to dysentery with blood and mucus in stool may not be symptomatic & can remain latent Severe amebiasis infections (invasive or fulminant amebiasis) Amoebic dysentery or Amoebic colitis * bacillary dysentery Amoebic liver abscesses : thru blood stream Diagnosis Treatment Amoebiasis

 Acanthamoeba keratitis Acanthamoeba amoebas are very common in nature (water, soil, air) Amoebae invade the cornea of the eye ( 각막 ) May result in permanent visual impairment or blindness Nearly always associated with contact lens use Acanthamoeba can survive in the space between lens & eye Disinfect contact lenses properly before wearing Remove contact lenses before any activity involving contact with water (showering, swimming, surfing, using a hot tub)

 Genus Plasmodium (malaria parasite) Sporozoa : sporogeny Gameocytes ( 생식모체 ) Within mosquito (vector), develop into sporozytes ( 유성생식 ) Sporozytes ( 포자체 ) Transmitted via the saliva of a mosquito to the human bloodstream Enter liver parenchyma cells, divide and form merozoites Merozoites ( 분자체 ) Released into the bloodstream and infect red blood cells Rapid division of the merozoites → destruction of RBCs Toxin production by the destroyed RBCs → the periodic chill-and-fever cycles that are the typical symptoms of malaria. Some merozoites may develop into gametocytes  Malaria

 Malaria Mosquito-born : Female Anopheles mosquito Fever, fatigue, vomiting and headaches Yellow skin, seizures, coma or death Symptoms usually begin 10 to 15 days after being bitten WHO million cases of malaria worldwide 584,000 to 855,000 deaths, mostly in Africa. Repeat the chill-fever cycle every 48 hours (Tertian malaria) Plasmodium falciparum : the most severe symptoms Plasmodium vivax : the most widespread form (Korea) Plasmodium ovale : relatively uncommon Repeat the chill-fever cycle every 72 hours (Quartan malaria) Plasmodium malariae Repeat the chill-fever cycle every 24 hour Plasmodium knowlesi : zoonotic (rare in humans)  Malaria

 Diagnosis Histopathological (Microscopic) : Giemsa stain  Prevention No vaccine available Occasional doses of sulfadoxine/pyrimethamine for infants and pregnant (after the first trimester of pregnancy)  Treatment : based on the species and the area Artemisinin-combination therapies (ACTs) : standard treatment worldwide for P. falciparum malaria. (an artemisinin) + (mefloquine, …) quinine + doxycycline (if an artemisinin is not available) Most drugs are active against the parasite forms in the blood. Primaquine : active against the dormant parasite liver forms and prevents relapses ( 조직형 치료 ) Malaria

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