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Yes it is possible to culture plasmodia but they don't grow in a simple constituted medium. Usually RPMI supplemented with serum and erythrocytes is used for growing plasmodia ex-vivo. This article discusses the issues related to plasmodial culture in detail. The authors say that sometimes a certain growth stage (in particular gametocyte) is lost on ...


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I don't know anything about this topic, but I did find this recent paper: Kamaljit Singh,Hardeep Kaur, Kelly Chibale, Jan Balzarini, Susan Little, Prasad V. Bharatam (2012) 2-Aminopyrimidine based 4-aminoquinoline anti-plasmodial agents. Synthesis, biological activity, structure–activity relationship and mode of action studies. European Journal of ...


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This may be the paper you are looking for: Ongaroraa DSB, Gutb J, Rosenthalb PJ, Masimirembwac CM, Chibale K. 2012. Benzoheterocyclic amodiaquine analogues with potent antiplasmodial activity: Synthesis and pharmacological evaluation. Bioorganic & Medicinal Chemistry Letters, 22(15): 5046–5050, doi:10.1016/j.bmcl.2012.06.010.


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The uninucleate sporozoites are injected by the mosquito into a human host. They mature in the liver parenchymal cells in schizonts. Each schizont releases into the blood flow 2,000 to 40,000 uninucleate merozoites. Each of them can infect a red blood cell. Here, a merozoite can release other 10 to 36 merozoites [1]. The numer of injected sporozites depends ...


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Selection pressure (1, 2). One way or the other, there were few enough people taking the drug that it didn't really "matter" to P. falciparum (the deadliest of the malaria-causing parasites) on a population level until recently. According to the 2014 paper Spread of Artemisinin Resistance in Plasmodium falciparum Malaria (3), the driver of Artemisinin ...


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Short Answer: Nothing prevents it, most Plasmodium (gametocytes/gametes/zygotes/ookinetes) are killed. Background: After lots of search, I finally found a definite answer about this. According to Smith et al, 2014, the survival rate of Plasmodium in the Anopheles gut is very low. At each developmental step during their life cycle, a large proportion of ...


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Disclaimer: I am trying to answer the question without finding any academic research on the topic. So, appreciate hypotheses and feel free to point out mistakes. Short Answer : Co- Evolution Broad Answer: 2 hypotheses The gamete stage of Malaria parasite simply co-evolved with Anopheles sp. to develop a protective mechanism to survive digestion in crop. ...


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I am afraid you may have to read your textbook more closely. The question on page 29 states that this equation models the proportion of infected humans. If $I$ $≥1$ that would mean that there are more people are infected than there are people in total - e.g. 3/2 of people are infected - this clearly doesn't make sense. Thus $1≥I$ when using this model.


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Indeed the process is even more interesting than thought: sporozoites actively attack Kupffer cells and let themselves get eaten! In a 2001 research, Pradel et al found that sporozoites pass through a layer of Kupffer cells in order to enter hepatocytes for the next stage of their life cycle. They observed that in rat liver cells, Plasmodium berghei and ...


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Very interesting explanation has been proposed by Ferreira A. et al. 2011. Briefly, red blood cells of individuals carrying homozygous point mutation in haemoglobin beta-chain tend to be more prone to disruption. Red blood cells are full of haemoglobin, so once their membrane is damaged, they release free haemoglobin and heme to the plasma. This is called ...


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The experience of a former adviser of mine was that some people who are not taking anti-malarial medication can still resist infection with Plasmodium falciparum, one of the parasites responsible for malaria. The parasite's life cycle includes stages inside the Anopheles sp. mosquito, and they are transmitted to human host via the female mosquito's saliva ...


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The heterozygous advantage generally lowers natural selection against the carriers of mutated alele, because it helps them to survive some specific conditions (which have to have some major impact on the survival rate). This means these individuals have bigger chances of reproducing, which means spread of the alele. Sickle cell anaemia is one good example ...


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What is the longest observed lifespan of a mosquito, especially of the species Anopheles arabiensis? Mean lifespan calculations for Anopheles arabiensis range from 14 days (Karoki, 2013)* to 21 days (Yamada et al. 2014)** *This Masters thesis tests efficacy of different drugs against An. arabiensis, 14 days is the mean control lifespan. **These An. ...


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Nice question! Basically, the mosquito does not only suck; it also injects some saliva into the host with its saliva glands. From National Geographic: The mosquito starts salivating as soon as it probes the [host]’s skin, releasing substances that prevent blood vessels from constricting, stop blood from clotting, and prevent inflammation. Sometimes, ...


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In a fairly recent review P W Hedrick surveys a number of gene variants associated with resistance to malaria. He explains that: The impact of malaria is thought to have increased between 10,000 and 5,000 years ago when there were the beginnings of agriculture and consequently more human settlements. During this period, the numbers of both the human ...


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I wasn't sure when I first read this, but this is actually a very interesting question. Right now there seem to be two completely divorced lines of inquiry that researchers are pursuing with respect to the antimalarial drugs. One group of researchers is working on working out the mechanism by which say, chloroquine and its ilk bind to and interfere with ...


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I would say that there are at least 2 explanations: Higher levels of free heme in the blood of individuals with sickle cell anaemia/sickle cell anaemia trait. Free heme is toxic to Plasmodium.sp Science. 1981 Nov 6;214(4521):667-9., detailed mechanism is described here: J Mol Med (Berl). 2008 Oct;86(10):1097-111. This effect is also observed in people ...


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The idea is rather simple. When an antibiotic is used, it becomes a driver to select for a mutant that has resistance towards the antibiotic. Let say the probability for that happening is P1 (Lets say 1 in 10, 0.1). When you use two antibiotics with different modes of attack, the probability of acquiring resistance to both is P1 x P2. (Let say P1 =0.1 and ...


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The statement in the question about the current distribution of these diseases is not strictly accurate, as shown by the graphic below. [Malaria graphic: Wikipedia user, Percherie (2006); TB graphic: Corbett et al. (2003)] However there is no disputing that the contemporary and historical geographical distribution of these diseases differ. Why? The crux ...


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There are 5 species of Malaria the can infect humans, and Chimpanzees and gorillas have also been found with 5 species, including vivax and falciparum. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4089193/ The parasite can go dormant in the liver for days to years, causing no symptoms and remaining undetectable in blood tests. They form what are called ...


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