《人体寄生虫学 Human parasitology》课程教学课件（讲稿）Lectures 12 entamoeba

FilariaeWuchereria bancrofti and Brugia malayi

Filariae . Wuchereria bancrofti and Brugia malayi

Morphological Differences of Microfilariae between WbancrotiandB.malayiSpeciesW.bancroftiB. malayiAppearancegraceful,sweepingcurvesirregular,stiff curvesSizelarger244-296x7μmsmaller177-230×6μmCephalic spaceshorter(1:1 or1:2)longer(2:1)(length:width)Nucleibodynucleiequal sized,clearlyunequal sized,coalescingdefined,countableuncountabletwoTerminalnucleino

Morphological Differences of Microfilariae between W. bancroti and B. malayi _ Species W. bancrofti B. malayi _ Appearance graceful, sweeping curves irregular, stiff curves _ Size larger 244-296× 7 µm smaller 177-230 × 6 µm _ Cephalic space shorter(1:1 or1:2) longer(2:1) (length:width) _ Nuclei body nuclei equal sized, clearly unequal sized, coalescing, defined, countable uncountable _ Terminal nuclei no two _

Life cycle (summary)1.Humanity is the only known definitive host for W.bancrofti while there is still another variety ofBmalayithat infects monkeys andfelines2.Infective stage: filariform larva(L3);3.Infectiveroute:byskin4.Site of inhabitation:lymphatic tissue5.Thefemaleproducelarvae--microfilariae6.show“nocturnalMicrofilariaeofbothspeciesperiodicity

Life cycle (summary) 1. Humanity is the only known definitive host for W. bancrofti while there is still another variety of B. malayi that infects monkeys and felines. 2. Infective stage: filariform larva(L3); 3. Infective route: by skin 4. Site of inhabitation: lymphatic tissue 5. The female produce larvae- microfilariae 6. Microfilariae of both species show “nocturnal periodicity

Clinical manifestation1.Acutestage:filarial fever; lymphangitis ; lymphadenitis;orchitis and inflammation of spermatic cord.2. Chronic stage: (obstructive filariasis)(1)Elephantiasis;(2) Chyluria only caused by W.bancrofti.(3) Hydrocele is only found in infection of W.bancrofti.First choice drug is diethylcarbamazine （ DECHetrazan)

Clinical manifestation 1. Acute stage: filarial fever ； lymphangitis ； lymphadenitis ； orchitis and inflammation of spermatic cord. 2. Chronic stage: (obstructive filariasis) (1) Elephantiasis； (2) Chyluria only caused by W. bancrofti. (3) Hydrocele is only found in infection of W. bancrofti. First choice drug is diethylcarbamazine ( DEC, Hetrazan )

The Scopeof Human Parasitology.Three major groups of human parasitesHelminth:multiple cells(Trematoda, Cestoda, Nematoda)Protozoa:one-cell organismArthropods:

The Scope of Human Parasitology •Three major groups of human parasites •Helminth: multiple cells ( Trematoda, Cestoda, Nematoda) •Protozoa: one-cell organism •Arthropods:

医学原虫Medical ProtozoaEntamoebahistolyticaLeishmaniaGiardiaintestinalis-Toxoplasma gondiiPlasmodiumTrichomonasvaginalisBalantidium coliPneumocystisCryptosporidium

Protozoa are one-celled animals foundworldwide in most habitats. Most species arefree living, but all higher animals are infectedwith one or more species of protozoa

Protozoa are one-celled animals found worldwide in most habitats. Most species are free living, but all higher animals are infected with one or more species of protozoa

Basic structure1. Cell membrane2. Cytoplasmorganelles: pseudopodium; flagellum;cilium3. Nucleus: two kinds of nucleivesicular;compact

Basic structure 1. Cell membrane 2. Cytoplasm organelles: pseudopodium; flagellum; cilium 3. Nucleus: two kinds of nuclei: vesicular; compact

Schematic diagram of a protozoan cellNuclearmembranekaryosomeendoplasmenectoplasmecnVesicular nuclearCellmembraneEC.FChromatinbeadsAchromaticfibrils

LifeCycle Stages The stages of parasitic protozoa that actively feedand multiply are frequently called trophozoites; insome protozoa, other terms are used for thesestages.Cysts are stages with a protective membrane orthickened wall

Life Cycle Stages • The stages of parasitic protozoa that actively feed and multiply are frequently called trophozoites; in some protozoa, other terms are used for these stages. • Cysts are stages with a protective membrane or thickened wall