Plasmodium protozoa

Antimalarial agents are effective against either erythrocytic or exoerythrocytic stages of plasmodium protozoa... 

Although the therapeutic benefits of the mercurials are by today s standards doubtful, and more likely outright harmful, quinine really is effective against malaria. In order to understand quinine, one must understand malaria. Malaria is a tropical and subtropical disease transferred to humans from the bite of the Anopheles mosquito, which carries the Plasmodium protozoa. Once in the bloodstream these parasites cause intermittent or remittent fevers, violent chills, headache, vomiting, and in severe cases coma and death. More often the malaria attacks are so debihtating that the sufferer succumbs to some secondary... 

Malaria is a disease caused by Plasmodium protozoa and transmitted by of mosquito vectors (Anopheles spp.), bites [93] to men, monkeys, rodents, birds, and reptiles [94]. The main agents involved in human malaria fever are four species of Plasmodium protozoa (single-celled parasites) P. falciparum, P. vivax, P. ovale, and P. malarie. Among these, P. falciparum accounts for the majority of infections, and it is the most lethal one. 

Malaria is transmitted by the bite of an infected female Anopheles mosquito, one of the few species of the insect capable of carrying the human malaria parasite. The responsible protozoa ate from the genus P/asmodium of which only four of some 100 species can cause the disease in humans. The remaining species affect rodents, reptiles, monkeys, birds, and Hvestock. The species that infect humans are P/asmodium falciparum Plasmodium vivax Plasmodium malariae and Plasmodium ovale. Note that concomitant multiple malaria infections are commonly seen in endemic areas, a phenomenon that further compHcates choice of treatment. 

Four different protozoa of the genus Plasmodium -P. falciparum, P. vivax, P. ovale and P malariae - can cause malaria. P. falciparum is the most virulent, being responsible for virtually all fatal malaria cases. Humans are infected by a feeding female Anopheles mosquito (Fig. 2). The clinical symptoms of malaria are associated with the development of the parasite within human red blood cells, while the liver stages remain asymptomatic. The following dtugs (in alphabetical order) are currently in use for the treatment of malaria [5]. 

The immune system protects humans and animals from microbial infections by such infectious agents as bacteria, yeasts and fungi, viruses and protozoa. These differ greatly not only in their size but in their structural and molecular properties, as well as in the ways in which they seek to infect our bodies. Some of these pathogens infect bodily fluids, some penetrate tissues and some even survive and multiply within individual host cells. These intracellular pathogens include viruses, some parasitic protozoa (such as Plasmodium, the causative agent of malaria, which infects erythrocytes) and... 

Many pathogenic protozoa. Including Trypanosoma brucei (trypanosomiasis or African sleeping sickness), Plasmodium falciparum (malaria), Leishmania species (leishmaniasis), and the intestinal parasites Giardia lamblia and Entamoeba histolytica, depend on farnesylated proteins for growth... 

To date, no effective vaccine has been developed for many parasites, notably the malaria-causing parasitic protozoa Plasmodium. One of the major difficulties in such instances is that parasites go through a complex life cycle, often spanning at least two different hosts. 

Malaria. An infectious disease endemic in parts of Africa, Asia, Turkey, the West Indies, Central and South America, and Oceania, caused by protozoa of the genus Plasmodium, and usually transmitted by the bites of infected anopheline mosquitoes. It is characterized by prostration associated with paroxysms of high fever, shaking chills, sweating, anemia, and splenomegaly, which may lead to death. 

The disease is caused by parasitic single-cell protozoa—a plasmodium (such as P. vivax or P.,falciparum) carried by female Anopheles mosquitoes (such as A. atroparvus or A.funestus). Malaria is characterized by bone-wracking painful periodic fevers, followed by chills, and, in some people, death. 

Plants with chlorophyll, or if without chlorophyll then without a true mycelium or plasmodium (no definite boundary exists between the Phycophyta and the Protozoa.) (Subdivision Phycophyta, algae)... 

Cinchona and its alkaloids, particularly quinine, have been used for many years in the treatment of malaria, a disease caused by protozoa, of which the most troublesome is Plasmodium falciparum. The beneficial effects of cinchona bark were first discovered in South America in the 1630s, and the bark was then brought to Europe by Jesuit missionaries. Religious intolerance initially restricted its universal acceptance, despite the widespread occurrence of malaria in Europe and elsewhere. The name cinchona is a mis-spelling derived from Chinchon. In an often quoted tale, now historically disproved, the Spanish Countess of Chinchon, wife of the viceroy of Peru, was reputedly cured of malaria by the bark. For... 

The causative organisms of malaria are protozoa of the genus Plasmodium, with four species known to infect humans only ... 

Intracellular protozoa of the phylum Apicomplexa such as plasmodium, toxoplasma, and eimeria have long been known to respond to sulfonamides and sulfones. This has led to the assumption that Apicomplexa must synthesize their own folate in order to survive. The reaction of 2-amino-4-hydroxy-6-hydroxymethyl-dihydropteridine diphosphate with />aminobenzoate to form 7,8-dihydropteroate has been demonstrated in cell-free extracts of the human malaria parasite Plasmodium falciparum. 2-Amino-4-hydroxy-6-hydroxymethyl-dihydropteridine pyrophosphokinase and 7,8-dihydropteroate synthase have also been identified. Sulfathiazole, sulfaguanidine, and sulfanilamide act as competitive inhibitors of p-aminobenzoate. It has not been possible to demonstrate dihydrofolate synthase activity in the parasites, which raises the possibility that 7,8-dihydropteroate may have substituted for dihydrofolate in malaria parasites. Similar lack of recognition of folate as substrate was also observed in the dihydrofolate reductase of Eimeria tenella, a parasite of chickens. 

Apicomplexa Protozoa Plasmodium, Toxoplasma, Malaria, coccidiosis, abortion,... 

Malaria is one of the world s most serious human health problems. According to the World Health Organization, more than 200 million new infections occur each year, many resulting in death [66]. The disease is caused by protozoa of the genus Plasmodium, most notably P. falciparum, which live in the intestines of female Anopheles mosquitoes. Humans are infected by bites from infected mosquitoes, by blood transfusions from infected donors, or by an expectant mother transmitting the disease to her child. Malaria is endemic in Sub-Saharan Africa, Central and South America, the Indian subcontinent and Oceania [67]. 

One class of protozoa called Telosporidea does not have any organ of locomotion. The organisms belonging to this class live within cells, tissues, cavities, and fluids of the body. The Plasmodium, causing malaria, belongs to this class. 

The French military physician Charles Louis Alphonse Lav-eran was credited with the 1880 discovery of the malaria protozoa Oscilliaria malarias, which was later termed Plasmodium. In malaria necropsies, Laveran noted the presence of dark pigmented bodies in the bloodstream and in the brain, spleen, and liver (7). This pigmented body was later characterized as a unique biomineral composed of a dimeric ferriprotopor-phyrin IX (Fe(III)PPIX) aggregate, which is known commonly as hemozoin (HZ). 

Alphonse Laveran, a French Army physician working in North Africa in the 1880s, was the first to observe malarial parasites in human blood. Their mode of transmission was not understood, however, until Ronald Ross, a British medical officer in India, found the organisms within the bodies of Anopheles mosquitoes. Malaria is caused by four species of parasitic protozoa Plasmodium vivax, P. ovale, P. malariae, satid P. falciparum. These organisms have complex life cycles involving several different developmental stages in both human and mos-... 

Other types of parasitic protozoa infect the blood or tissues of their hosts. These protozoa are typically transmitted through another organism, called a vector, which carries the parasite before it enters the final host. Often the vector is an invertebrate, such as an insect, that itself feeds on the host and passes the protozoan on through the bite wound. Some of the most infamous of these protozoa are members of the genera Plasmodium, that cause malaria Trypanosoma, that cause African sleeping sickness and Leishmania, which leads to a number of debilitating and disfiguring diseases. 

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