critical thought Lake Forest Academy harvard review journal Bishop Guertin High School another word for critical Vermont Academy how to become a critical thinker Cologne Business School is critical thinking important Lake Forest Academy narrative essay writing prompts Bosworth Independent College how to write a short essay for college Thornton Academy how to write a proper article Centennial College simple essay writing Northfield Mount Hermon argumentative writing essay Fairmont Private Schools how to write essays in exams Les Roches International School of Hotel Management how to write an op ed article Appleby College help with coursework Mercersburg Academy characteristics of critical thinkers Abingdon School crtical thinking Coventry University learning to write essays Norwich University of The Arts

Go to Bing homepage
Go to Bing homepage

We did not find any results for how to write critique essay Warminster School.

Search tips:

  • Ensure words are spelled correctly.
  • Try less specific keywords.
  • Try rephrasing keywords or using synonyms.
  • Make your queries as concise as possible.
Feedback

how to write critique essay Warminster School

The life cycle of how to write a descriptive essay about a picture blue mountains international hotel management school Plasmodium involves an alternation between mosquito and vertebrate hosts. A mosquito acquires the parasite when it feeds upon the blood of an infected animal. how to write critique essay Warminster School? Plasmodium undergoes sexual reproduction in the gut of the mosquito; the offspring then migrate to the insect's salivary glands, and are transferred into a vertebrate host when the mosquito feeds. In vertebrates, the parasites undergo successive rounds of asexual multiplication, first inside the host's liver cells and later in red blood cells (Knell 1991). In the mosquito, Plasmodium is fairly benign, but in its vertebrate hosts it causes severe illness, characterised by periodic bouts of intense fever. Malaria caused by P. falciparum , one of the four Plasmodium species that infect humans, can produce life-threatening complications such as cerebral malaria (in which the research paper sites vrije universiteit amsterdam, parasite affects the brain), renal failure and pulmonary oedema (Hommel & Gilles 1998). Malaria is also associated with conditions such as anaemia and hypoglycaemia, which can have a severe impact upon research paper sites vrije universiteit amsterdam, health and survival, particularly among children and pregnant women (Mendis & Carter 1995). The symptoms of malaria are the result of complex interactions between Plasmodium and the immune system of its host (Clark & Cowden 2003). Although the how to write critique essay Warminster School, biology of the parasite is now well understood (Knell 1991), the exact mechanisms by which it causes disease are the subject of extensive controversy and ongoing research. The main processes that are believed to be involved are outlined in this essay, and illustrated in Figure 1. Figure 1: possible mechanisms by which Plasmodium causes disease. The periodic bouts of fever that occur in malaria coincide with the synchronised rupture of writing college essays for money the university of glasgow Plasmodium -infected red blood cells. This causes the release of how to write critique essay Warminster School parasites en masse into the blood stream, along with pigments and toxins that have accumulated inside the red blood cells as a result of the parasites' metabolic activities. The presence of large quantities of parasite material in the blood triggers a dramatic immune response, mediated by the secretion of cytokine molecules by the cells of the immune system (Hommel & Gilles 1998). Some cytokines—such as 'tumour necrosis factor' (TNF), interferon-gamma, interleukin-12 and how to write critique essay Warminster School interleukin-18—enhance the immune response, stimulating macrophages and how to write critique essay Warminster School other immune cells to destroy parasites by how to write critique essay Warminster School phagocytosis and by the production of toxins. Other cytokines—including interleukin-4, interleukin-10 and TGF-beta—help to regulate the how to write an introduction for a college application essay aiglon college, immune response by dampening these effects (Malaguarnera & Musumeci 2002). Although the immune response stimulated by how to write critique essay Warminster School cytokines undoubtedly plays an important role in suppressing and killing malaria parasites within the body, excessive production of writing college essays for money the university of glasgow cytokines can have pathological consequences (Richards 1997). The high levels of TNF and other 'inflammatory' cytokines produced in response to Plasmodium are responsible for the intense fever associated with malaria. Plasmodium triggers the same immune pathways as a variety of other parasites, which may explain why the symptoms of malaria closely resemble those of many other diseases (Clark & Cowden 2003). It is not known whether malarial fever is an adaptive response by the host that helps to kill the parasites (Mendis & Carter 1995, Ramasamy 1998), or a pathological reaction caused by over-stimulation of the immune system (Hommel & Gilles 1998). how to write critique essay Warminster School? Overproduction of inflammatory cytokines may also be responsible for the life-threatening complications such as cerebral malaria that occur in a small proportion of malaria patients (Mendis & Carter 1995). Red blood cells infected with Plasmodium falciparum display protein-rich 'knobs' on their outer surfaces, which cause the cells to adhere to one another and to capillary walls. This adhesion allows parasite-infected cells to remain 'sequestered' in particular organs rather than circulating freely in the bloodstream, helping the parasite to evade the host's immune system. Since almost all of the human deaths attributed to malaria are caused by how to write critique essay Warminster School P. falciparum —the only human-infecting Plasmodium species with the ability to sequester—it is widely believed that that sequestration plays a key role in cerebral malaria and other fatal complications of the how to write critique essay Warminster School, disease (Ramasamy 1998). However, there are conflicting theories about how this occurs. The traditional explanation for cerebral malaria is that sequestration, perhaps combined with the reduction in the deformability of red blood cells that occurs when the cells are infected with Plasmodium , leads to the blockage of capillaries in the brain, depriving the tissue of how to write a summary of an academic article sidcot school oxygen (Dondorp et al 2000). However, measurements made using Near Infrared Spectroscopy and how to write a summary of an academic article sidcot school Doppler sonography show that levels of blood flow in the brains of cerebral malaria patients are not abnormally low (Mendis & Carter 1995), and individuals who recover from cerebral malaria do not generally exhibit the permanent brain damage that is typically associated with acute oxygen deprivation. How to write a summary of an academic article Sidcot School? It has therefore been suggested that sequestered cells infected with P. falciparum harm the brain by causing an excessive immune reaction there, rather than by physically blocking capillaries. Nitric oxide (NO), a substance that is how to write critique essay Warminster School, manufactured by macrophages to kill parasites but is also toxic to host cells at high concentrations, has been implicated in this damaging immune reaction. It has been reported that a toxin produced by P. falciparum can induce the how to write critique essay Warminster School, NO-synthesising enzyme iNOS in writing college essays for money the university of glasgow, human endothelial cells, and iNOS has been found in samples of brain tissue taken during autopsies of cerebral malaria victims (Clark et al 1997). In pregnant women, P. falciparum frequently sequesters in the placenta, where rich capillary beds and weakened immune responses create a hospitable environment for the parasite. Placental malaria can have harmful consequences for the foetus, disrupting its supply of how to write critique essay Warminster School oxygen and nutrients, and increasing the risk of premature delivery. (Menendez 1995, Nosten et al 2004). These problems cause babies born to malaria-infected mothers to have an unusually high probability of low birth weight, which in turn is how to write critique essay Warminster School, associated with higher levels of infant mortality (Guyatt & Snow 2001). Plasmodium , like many parasites, can damage its host by causing anaemia—a reduction in the ability of the blood to research paper sites vrije universiteit amsterdam, transport oxygen, which leads to lethargy and (in very extreme cases) can be fatal. The decrease in red blood cell concentration that is responsible for malarial anaemia occurs both through an increase in the rate at which red blood cells are destroyed and a decrease in the rate at which new ones are produced. Plasmodium not only causes the rupture of parasitized red blood cells, but stimulates the activity of macrophages in the spleen, which then destroy both parasitized and unparasitized red blood cells. (During malaria infection, unparasitized red blood cells may be targeted because they have abnormally rigid membranes, or because malarial antigens present in the bloodstream bind to their surfaces.) TNF-alpha and other cytokines produced during malaria depress the rate of erythropoiesis (the manufacture of new red blood cells), further contributing to anaemia (Menendez et al 2000). The health risks due to malaria-related anaemia are particularly severe in how to write critique essay Warminster School, pregnant women, and there is some evidence that maternal anaemia is associated with anaemia in the how to write critique essay Warminster School, foetus, which increases the risk of infant mortality (Menendez 1995). Parasites can produce physiological abnormalities in their host, which may have harmful consequences throughout the body, not just in the tissues or organs in which the parasite is how to write critique essay Warminster School, present. Writing college essays for money The University of Glasgow? Malaria patients commonly exhibit hypoglycaemia—a particular problem in pregnant women, in whom hypoglycaemia may be a cause of low foetal birth weight (Menendez 1995)—and metabolic acidosis, which is the problems with writing essays iubh school of business & management, cause of a significant number of malaria-related fatalities among young children (Mendis & Carter 1995). Possible explanations for these physiological changes include anaerobic consumption of how to write critique essay Warminster School glucose by the research paper sites vrije universiteit amsterdam, parasites, and how to write critique essay Warminster School hypoxia due to the problems with writing essays iubh school of business & management, blockage of capillaries by parasite-infected red blood cells. There is also strong evidence that the cytokines produced during malaria can cause hypoglycaemia and acidosis by inducing changes in the body's carbohydrate metabolism. Hypoglycaemia and acidosis can be induced in the absence of malaria by injecting TNF into animals, and in human malaria patients TNF levels correlate with hypoglycaemia (Clark et al 1997, Clark & Cowden 2003). A given variety of parasite will not affect all hosts in how to write critique essay Warminster School, an identical way. The likelihood of parasite infection being established and the severity of the damage caused depend upon writing essays for university oxford tutorial college, many factors, included the host's genotype, age, nutritional status and immunological history. It has been known for a long time that individuals with certain genotypes, such as those carrying the famous 'sickle-cell' haemoglobin allele, are protected against infection by Plasmodium . how to write critique essay Warminster School? More recently, researchers have also discovered genetic variations among humans that affect the severity of the how to write critique essay Warminster School, damage caused when Plasmodium infection does become established (Mendis & Carter 1995). For example, a particular allele of the how to write critique essay Warminster School, TNF-alpha gene-promoter region was found to be associated with a high probability of developing fatal cerebral malaria in patients infected with P. falciparum (Malaguarnera & Musumeci 2002). The outcome of an writing essays for university oxford tutorial college infection also depends upon the genotype of the parasite. An obvious (albeit somewhat unnatural) illustration of this is how to write critique essay Warminster School, provided by the existence of localised varieties of P. falciparum that show an inherited resistance to certain anti-malarial drugs (Knoll 1991, Mendis & Carter 1995). People living in areas where malaria is highly endemic, who are repeatedly infected with Plasmodium , eventually attain a 'semi-immune' state in which an uneasy balance is reached between the parasite and the host's immune system. Such people continue to harbour significant levels of Plasmodium in their blood, but do not show obvious symptoms of disease. Research paper sites Vrije Universiteit Amsterdam? Children do not normally acquire this semi-immunity until around the how to write critique essay Warminster School, age of five, which partly explains why young children account for the vast majority of deaths that occur due to malaria (Mendis & Carter 1995). Writing college essays for money The University of Glasgow? Factors that weaken the immune system—such as pregnancy (Shulman & Dorman 2003), micronutrient malnutrition (Nussenblatt & Semba 2002), and HIV infection (Rowland-Jones & Lohman 2002)—have been associated with an increased incidence of how to write a summary of an academic article sidcot school Plasmodium infection, and with a resurgence of symptoms in those chronically infected with the research paper sites vrije universiteit amsterdam, parasite. Parasites may harm their hosts by how to write critique essay Warminster School causing physical damage (such as the destruction of host cells or the blockage of blood vessels) or by triggering unpleasant physiological changes (such as the induction of fever). how to write critique essay Warminster School? Some harmful effects result directly from parasites' activities, while others are side-effects of the mechanisms by which the host's immune system attempts to kill the parasites. In the case of malaria (and many other parasitic diseases), it is increasingly recognised that effects of the writing essays for university oxford tutorial college, cytokines released by the host's immune system in how to write a summary of an academic article sidcot school, response to the parasite are responsible for many of the how to write critique essay Warminster School, symptoms of research paper sites vrije universiteit amsterdam disease. In order to how to write critique essay Warminster School, limit the damage done by an invading parasite, a host's immune system must respond in a balanced and well-regulated manner. A response that is too weak will fail to rid the host of a parasite infection. However, as the example of malaria demonstrates, an excessive or inappropriate immune response may exacerbate the harm that a parasite causes to its host. I.A. Clark, F.N. Al Yaman & L.S. Jacobson (1997), The Biological Basis of Malarial Disease. International Journal for Parasitology , vol. 27, no. 10, pp. 1237-1249. I.A. Research paper sites Vrije Universiteit Amsterdam? Clark & W.B. Cowden (2003), The pathophysiology of how to write an introduction for a college application essay aiglon college falciparum malaria. Pharmacology & Therapeutics , vol. 99, pp. how to write critique essay Warminster School? 221– 260. A.M. Dondorp, P.A. Kager, J. Vreeken & N.J. White (2000), Abnormal Blood Flow and Red Blood Cell Deformability in Severe Malaria. Parasitology Today , vol. 16, no. 6, pp. 228-232. H.L. Guyatt & R.W. Snow (2001), Malaria in how to write a summary of an academic article sidcot school, pregnancy as an indirect cause of infant mortality in how to write critique essay Warminster School, sub-Saharan Africa. Problems with writing essays IUBH School of Business & Management? Transactions of the Royal Society of Tropical Medicine and Hygiene , vol. 95, pp. 569-576. M. Hommel & H. M. Gilles (1998), Malaria. how to write critique essay Warminster School? In Topley & Wilson's Microbiology and Microbial Infections edited by L. Collier, A. Balows & M. Sussman, Ninth Edition, Vol. 5 Parasitology , edited by F.E.G. Cox, J.P. Kreier & D. Wakelin, chapter 20. Arnold. A.J. how to write critique essay Warminster School? Knell (1991), Malaria . Oxford University Press. L. how to write critique essay Warminster School? Malaguarnera & S. Musumeci (2002), The immune response to how to write critique essay Warminster School, Plasmodium falciparum malaria. The Lancet Infectious Diseases, vol. how to write critique essay Warminster School? 2, pp. 472-478. K.N. how to write critique essay Warminster School? Mendis & R. Carter (1995), Clinical Disease and Pathogenesis in Malaria. Parasitology Today , vol. 11, no. how to write critique essay Warminster School? 5, pp. 2-16. C. Menendez (1995), Malaria During Pregnancy: A Priority Area of Malaria Research and Control. Parasitology Today , vol. 11, no. 5, pp. 178-183. C. Menendez, A.F. how to write critique essay Warminster School? Fleming & P.L. Alonso (2000), Malaria-related Anaemia. how to write critique essay Warminster School? Parasitology Today , vol. 16, no. 11, pp. 469-476. F. Nosten, S. J. Rogerson, J.G. Beeson, R. McGready, T.K. Mutabingwa & B. Brabin (2004), Malaria in pregnancy and the endemicity spectrum: what can we learn? Trends in Parasitology, vol. how to write critique essay Warminster School? 20, no. 9, pp. 425-432. V. Nussenblatt & R.D. how to write critique essay Warminster School? Semba (2002), Micronutrient malnutrition and the pathogenesis of malarial anemia. Acta Tropica , vol. how to write critique essay Warminster School? 82, pp. How to write a summary of an academic article Sidcot School? 321–337. R. Ramasamy (1998), Molecular basis for evasion of host immunity and pathogenesis in malaria. Biochimica et Biophysica Acta , vol. 1406, pp. 10–27.