Academic literature on the topic 'Live parasites'
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Journal articles on the topic "Live parasites"
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Harwood, David. "Parasites in the goat." Livestock 19, no. 6 (November 2, 2014): 360–67. http://dx.doi.org/10.12968/live.2014.19.6.360.
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Combes, C., and S. Morand. "Do parasites live in extreme environments? Constructing hostile niches and living in them." Parasitology 119, S1 (December 1999): S107—S110. http://dx.doi.org/10.1017/s0031182000084663.
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SUMMARYWe develop the hypothesis that parasites do not invade extreme environments, i.e. hostile hosts, but rather ‘create’ them. We argue that parasites may have driven the evolution of the constitutive and adaptive immune system. This leads to several implications. First, parasites respond to ‘genes to kill’ by ‘genes to survive’ and this triggers an indefinite selection of measures and counter-measures. Second, these revolutionary arms races may lead to local adaptation, in which parasite populations perform better on local hosts. Third, the evolution of the immune system, whose responses are predictable, may allow parasites to specialize, to evade and even to manipulate. Finally we show that the correlations between the increase in the antibody repertoire, the expansion of MHC loci and parasite pressures support our hypothesis that both host complexity and parasite pressures can be invoked to explain the diversity of antibodies, T-receptors and MHC molecules.
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Buckner, Frederick S., Aaron J. Wilson, and Wesley C. Van Voorhis. "Detection of Live Trypanosoma cruzi in Tissues of Infected Mice by Using Histochemical Stain for β-Galactosidase." Infection and Immunity 67, no. 1 (January 1, 1999): 403–9. http://dx.doi.org/10.1128/iai.67.1.403-409.1999.
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ABSTRACT The pathogenesis of tissue damage in chronic Trypanosoma cruzi infection has been a subject of long-standing debate. Conventional staining methods reveal a paucity of parasites in tissues from chronically infected individuals, which has led to the theory that the pathologic findings may be primarily autoimmune in origin. Immunostaining for T. cruzi antigens or in situ PCR methods show evidence for parasite components in chronic tissues; however, these methods do not address whether the stained material represents parasite debris or live organisms. An improved method for detecting intact T. cruzi in tissues was developed by making a genetically engineered strain that expresses Escherichia coli β-galactosidase. The expression of this enzyme allows the detection of T. cruzi in tissues by using the histochemical stain 5-bromo-4-chloro-3-indolyl-β-d-galactopyranoside (X-Gal). The technique was used to monitor tissue parasitism and its relation to pathologic findings in the mouse model of Chagas’ disease. Parasites were easily visible as bright blue structures in skeletal muscle, heart, bladder, peripheral nerve, liver, spleen, adrenal gland, brain, and adipose tissue in acutely infected mice. The number of viable parasites diminished >100-fold when tissues from 3-week-infected mice were compared with those from 10-month-infected mice. However, even at the lower level, parasites were clearly recognizable in sections of skeletal muscle and bladder at the 10-month time point. Inflammation remained robust in skeletal muscle, bladder, and sciatic nerve despite the near disappearance of parasites, suggesting three possibilities: exuberant host reactions to the few remaining parasites, autoimmune inflammation, or reactions to retained parasite antigens in the tissues.
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Rénia, Laurent, Anne Charlotte Grüner, Marjorie Mauduit, and Georges Snounou. "Vaccination against malaria with live parasites." Expert Review of Vaccines 5, no. 4 (August 2006): 473–81. http://dx.doi.org/10.1586/14760584.5.4.473.
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Tabbara, Khaled S., Nathan C. Peters, Farhat Afrin, Susana Mendez, Sylvie Bertholet, Yasmine Belkaid, and David L. Sacks. "Conditions Influencing the Efficacy of Vaccination with Live Organisms against Leishmania major Infection." Infection and Immunity 73, no. 8 (August 2005): 4714–22. http://dx.doi.org/10.1128/iai.73.8.4714-4722.2005.
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ABSTRACT Numerous experimental vaccines have been developed with the goal of generating long-term cell-mediated immunity to the obligate intracellular parasite Leishmania major, yet inoculation with live, wild-type L. major remains the only successful vaccine in humans. We examined the expression of immunity at the site of secondary, low-dose challenge in the ear dermis to determine the kinetics of parasite clearance and the early events associated with the protection conferred by vaccination with live L. major organisms in C57BL/6 mice. Particular attention was given to the route of vaccination. We observed that the rapidity, strength, and durability of the memory response following subcutaneous vaccination with live parasites in the footpad are even greater than previously appreciated. Antigen-specific gamma interferon (IFN-γ)-producing T cells infiltrate the secondary site by 1.5 weeks, and viable parasites are cleared as early as 2.5 weeks following rechallenge, followed by a rapid drop in IFN-γ+ CD4+ cell numbers in the site. In comparison, intradermal vaccination with live parasites in the ear generates immunity that is delayed in effector cell recruitment to the rechallenge site and in the clearance of parasites from the site. This compromised immunity was associated with a rapid recruitment of interleukin-10 (IL-10)-producing CD4+ T cells to the rechallenge site. Treatment with anti-IL-10-receptor or anti-CD25 antibody enhanced early parasite clearance in ear-vaccinated mice, indicating that chronic infection in the skin generates a population of regulatory cells capable of influencing the level of resistance to reinfection. A delicate balance of effector and regulatory T cells may be required to optimize the potency and durability of vaccines against Leishmaniasis and other intracellular pathogens.
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Omeji, S., S. G. Solomon, and E. S. Idoga. "A Comparative Study of the Common Protozoan Parasites ofClarias gariepinusfrom the Wild and Cultured Environments in Benue State, Nigeria." Journal of Parasitology Research 2011 (2011): 1–8. http://dx.doi.org/10.1155/2011/916489.
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A total of one hundred and twentyClarias gariepinuscomprising 30 dead and 30 live fishes were examined for protozoan parasites infestation, sixty each from the wild and a pond (cultured environment) over a period of six months.Ichthyophthirius multifiliiswas the most common protozoan parasites found inC. gariepinusfrom the wild (River Benue) and cultured (pond) environments. These protozoan parasites constitute 37.08% of the total parasites encountered for fishes in the pond and 42.51% of fishes in the wild. Among the body parts of the sampled fishes from the pond, the gills had the highest parasite load (38.86%). Also, the gills had the highest parasite load (40.54%) among the body parts of the fishes sampled from the wild. Fishes not infested with any protozoan parasites from the pond constituted 36.70% of the total fish sampled. On the other hand, fishes not infested with any protozoan parasites from the wild constituted 31.65% of the total fish sampled. Female fishes had more protozoan parasites than the male fishes. Bigger fishes of total length (25–48 cm) had more parasite load than the smaller ones (19–24 cm). Also, fishes between 150–750 g had more parasite load than the smaller ones of less than 150 g. Protozoan parasite load of fish from the cultured environment (pond) did not differ significantly (P<0.05) from those from River Benue (wild).
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Bhattacharya, Parna, Ranadhir Dey, Pradeep K. Dagur, Michael Kruhlak, Nevien Ismail, Alain Debrabant, Amritanshu B. Joshi, et al. "Genetically Modified Live Attenuated Leishmania donovani Parasites Induce Innate Immunity through Classical Activation of Macrophages That Direct the Th1 Response in Mice." Infection and Immunity 83, no. 10 (July 13, 2015): 3800–3815. http://dx.doi.org/10.1128/iai.00184-15.
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Visceral leishmaniasis (VL) causes significant mortality and there is no effective vaccine. Previously, we have shown that genetically modifiedLeishmania donovaniparasites, here described as live attenuated parasites, induce a host protective adaptive immune response in various animal models. In this study, we demonstrate an innate immune response upon infection with live attenuated parasites in macrophages from BALB/c mice bothin vitroandin vivo. In vitroinfection of macrophages with live attenuated parasites (compared to that with wild-type [WT]L. donovaniparasites) induced significantly higher production of proinflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin-12 [IL-12], gamma interferon [IFN-γ], and IL-6), chemokines (monocyte chemoattractant protein 1/CCL-2, macrophage inflammatory protein 1α/CCL-3, and IP-10), reactive oxygen species (ROS), and nitric oxide, while concomitantly reducing anti-inflammatory cytokine IL-10 and arginase-1 activities, suggesting a dominant classically activated/M1 macrophage response. The classically activated response in turn helps in presenting antigen to T cells, as observed with robust CD4+T cell activationin vitro. Similarly, parasitized splenic macrophages from live attenuated parasite-infected mice also demonstrated induction of an M1 macrophage phenotype, indicated by upregulation of IL-1β, TNF-α, IL-12, and inducible nitric oxide synthase 2 and downregulation of genes associated with the M2 phenotype, i.e., the IL-10, YM1, Arg-1, and MRC-1 genes, compared to WTL. donovani-infected mice. Furthermore, anex vivoantigen presentation assay showed macrophages from live attenuated parasite-infected mice induced higher IFN-γ and IL-2 but significantly less IL-10 production by ovalbumin-specific CD4+T cells, resulting in proliferation of Th1 cells. These data suggest that infection with live attenuated parasites promotes a state of classical activation (M1 dominant) in macrophages that leads to the generation of protective Th1 responses in BALB/c mice.
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Chamidah, Dina. "Jenis-jenis Benalu dengan Tanaman Inang Pada Ruang Terbuka Hijau Kota Surabaya." Ibriez : Jurnal Kependidikan Dasar Islam Berbasis Sains 2, no. 2 (December 29, 2017): 215–24. http://dx.doi.org/10.21154/ibriez.v2i2.38.
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Green Open Space serves as a container for human life, both individually and in groups, as well as other creature containers to live and thrive in a sustainable manner. The beauty and value of the benefits of plants in the Green Open Space are often disturbed by the presence of parasites. The presence of parasites often indicates the occurrence of disturbance or damage to host plants that paraded. Benalu has been widely known by the community, but has never received attention in handling it. There has been little research on crop damage or loss caused by parasites. The purpose of this research is to know the presence or absence of parasite in green open space of Surabaya city and to know identification of dominance of parasite with the host plant in green open space of Surabaya city. Observation on the type of parasite with its host in the green open space of Surabaya City, East Java had been conducted in some spots, yield : Center Surabaya area, North Surabaya area, East Surabaya area, South Surabaya area, West Surabaya area. The observation methodology is by cruising (cruise method) by visiting the place where much overgrown vegetation plants at each point there are 500 vegetation plants which allows to be a parent host. The results of the observation obtained 3 types of parasites, 1 type of parasite of the tribe Crypteroniaceae which was parasite 39 species of host plants i.e. Henslowia frutescens .Champ. and 2 types of parasites of the tribe Loranthaceae, i.e. Loranthus Sp and Macrosolen cochinchinensis (Lour.) van Tiegh.
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Jarra, William, and Georges Snounou. "Only Viable Parasites Are Detected by PCR following Clearance of Rodent Malarial Infections by Drug Treatment or Immune Responses." Infection and Immunity 66, no. 8 (August 1, 1998): 3783–87. http://dx.doi.org/10.1128/iai.66.8.3783-3787.1998.
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ABSTRACT Detection and analysis of pathogens by PCR plays an important role in infectious disease research. The value of these studies would be diminished if nuclear material from dead parasites were found to remain in circulation for extended periods and thus result in positive amplification. This possibility was tested in experimental rodent malaria infections. Blood samples were obtained from infected mice during and following drug or immune clearance of Plasmodium chabaudi chabaudi parasitemias. Detection of parasite DNA by a sensitive Plasmodium-specific PCR amplification assay was associated with the presence of viable parasites, as detected by subinoculation. No parasite DNA could be detected by PCR 48 h after the injection of killed parasites into mice. Nuclear material from parasites removed by drug or immune responses is rapidly cleared from the circulation and does not contribute significantly to amplification. Thus, results from PCR analysis of malaria-infected blood accurately reflect the presence of live parasites.
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Waterfall, Martin, Antony Black, and Eleanor Riley. "γδ+ T Cells Preferentially Respond to Live Rather than Killed Malaria Parasites." Infection and Immunity 66, no. 5 (May 1, 1998): 2393–98. http://dx.doi.org/10.1128/iai.66.5.2393-2398.1998.
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ABSTRACT We have compared the in vitro responses of peripheral blood T cells from malaria-unexposed donors to live Plasmodium falciparumschizonts, freeze-thawed schizont extracts (P. falciparumschizont extracts [PfSE]), and parasite culture supernatants. We show that the cells responding to PfSE and parasite culture supernatants are predominantly CD4+ TCRαβ+ while in the presence of live schizonts there is an additional activation of TCRγδ+ cells. Activation of TCRγδ+cells in response to PfSE was seen only when irradiated autologous feeder cells or recombinant interleukin-2 (IL-2) was added to the cultures. Live schizonts but not PfSE induced significant IL-2 production in vitro in the first 5 days after stimulation, suggesting that induction of early IL-2 by live parasites may contribute to the marked activation of the TCRγδ+ population.
Dissertations / Theses on the topic "Live parasites"
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Birkett, Sally Jo. "Effects of gamma-irradation on leishmania Mexicana parasites and their use as a live vaccine." Thesis, University of Liverpool, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526842.
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Renhe, Daniela Chaves. "Malária grave murina: análise histopatológica e imunológica em tecido cerebral e pulmonar de camundongos C57BL/ imunizados com parasitos vivos de fase sanguínea de Plasmodium berghei (Cepas ANKA e NK65) e desafiados com Plasmodium berghei ANKA." Universidade Federal de Juiz de Fora (UFJF), 2015. https://repositorio.ufjf.br/jspui/handle/ufjf/3678.
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Dentre as várias estratégias utilizadas com o intuito de induzir imunidade antimalárica está o uso de doses ultra-baixas de parasitos vivos de fase sanguínea dos plasmódios. Contudo, apesar desse método aparentemente induzir imunidade transcendente a cepa e espécie dois pontos precisam ser esclarecidos: 1- nenhum estudo tem avaliado se imunizações com parasitos vivos de baixa virulência são capazes de proteger contra o desenvolvimento de quadros graves da doença incluindo malária cerebral; 2 - considerando que crianças africanas frequentemente apresentam malária grave somente após reexposição a parasitos altamente virulentos, a relação entre o uso de parasitos vivos e o possível desenvolvimento de infecções graves precisa ser investigada. Para esclarecer tais questões, animais C57BL/6 foram imunizados uma ou duas vezes com 10³ hemácias infectadas por P. berghei NK65 ou P. berghei ANKA e posteriormente desafiados com 10^5 hemácias parasitadas por P. berghei ANKA. Imediatamente após primeira imunização, somente animais imunizados com P. berghei NK65 apresentaram níveis positivos de anticorpos IgG, os quais reconheceram tanto o antígeno homólogo quanto heterólogo. Independentemente do protocolo de imunização, animais imunizados uma vez apresentaram, tanto no cérebro quanto nos pulmões, menos áreas com acúmulo de hemácias e infiltrado inflamatório que animais somente desafiados ou imunizados duas vezes. Apesar das imunizações (uma ou duas vezes) com P. berghei ANKA e P. berghei NK65 terem controlado o desenvolvimento da parasitemia sanguínea por P. berghei ANKA, somente animais imunizados com P. berghei NK65 permaneceram vivos por até 30 dias após desafio experimental com P. berghei ANKA. Tanto no cérebro quanto nos pulmões, os níveis de TNF-α tenderam a elevar-se em relação ao IFN-ꝩ em animais que sofreram dois ciclos de imunizações, o que pode espelhar os maiores danos teciduais observados nesses animais. Contudo, os padrões de citocinas antiinflamatórias e pró-inflamatórias observados nesse estudo não explicam a mortalidade ou sobrevivência observada em animais imunizados com P. berghei ANKA e P. berghei NK65, respectivamente, e desafiados com P. berghei ANKA.
The use of ultra-low doses of live blood stage parasites is one of several strategies used to induce anti-malarial immunity. Although this method apparently induces cross-species and strain-transcendent immune response, there are two points that need to be explored: 1) no study has assessed whether immunization with live low virulence parasites is able to protect against the development of severe malaria, including cerebral malaria; 2) African children often develop severe malaria only after re-exposure to highly virulent parasites. Thus, the relationship between the use of live parasites and possible development of serious infections needs to be investigated. To clarify these two points, C57BL/6 mice were immunized once or twice with 10³ erythrocytes infected with P. berghei NK65 or P. berghei ANKA, and subsequently challenged with 10^5 P. berghei ANKA-parasitized erythrocytes. After the first immunization, only P. berghei NK65 immunized animals showed positive levels of IgG antibodies, which recognizes both homologous and heterologous antigen. In animals immunized only once, both brain and lungs exhibited fewer regions with accumulation of red blood cells and inflammation, when compared to control group or twice-immunized animals. Regardless of immunization protocols, all of the mice exhibit controlled development of P. berghei ANKA blood parasitemia. However, only P. berghei NK65 immunized animals remained alive 30 days after the being challenged with P. berghei ANKA. The TNF-α levels, on both brain and lungs, tended to rise in relation to IFN-ꝩ in animals undergoing two cycles of immunizations, which might reflect the higher tissue damage observed in these animals. However, the patterns of pro and anti-inflammatory cytokines present do not explain the observed mortality and survival rate in animals immunized with P. berghei ANKA and P. berghei NK65, respectively.
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Davis, Richard Elliot. "Neutrophil responses to infection with leishmania parasites: MHC class II-expression and parasite life-stage interactions." Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/2200.
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The vector-borne protozoan Leishmania spp. cause the spectrum of disease known as leishmaniasis in human and animal hosts. The most common manifestations of leishmaniasis are the chronic, ulcerative skin disease cutaneous leishmaniasis (CL), and the more serious visceral leishmaniasis (VL) in which parasites take up residence in internal organs, causing death if not treated. The role of neutrophils (PMNs) in the immune response to CL and VL is unclear. It is s generally thought that PMNs are only a short-lived effector cell, and have been disregarded as playing a role in chronic Leishmania spp. infection. As both CL and VL are diseases characterized by increased inflammatory immune mediators, we hypothesized that PMNs from human or animal models of chronic leishmaniasis would display different properties from PMNs from healthy controls. We found in a subset of CL and VL patients circulating PMNs expressing HLA-DR, the human form of MHC class II, a molecule thought to be restricted primarily to professional antigen cells. When we examined PMNs recruited to CL skin lesions in human patients, or similar lesions in experimental murine model of CL, we found significantly increased MHC class II+ PMNs. Circulating HLA-DR+ PMNs also expressed the co-stimulatory molecules CD80, CD86 and CD40. While this suggested an antigen-presenting cell-like phenotype by these HLA-DR+ PMNs, compared to conventional HLA-DR- PMNs, HLA-DR+ PMNs showed not only a neutrophil-like appearance and function, but in fact increased activation, degranulation, intracellular MPO and phagocytosis of parasites and zymosan particles. Incubation of healthy control whole blood with inflammatory cytokines resulted in increased HLA-DR+ PMNs and the presence of hladrb1 mRNA, suggesting a connection between neutrophil “priming” and upregulation of HLA-DR.
In addition to HLA-DR+ PMNs in CL patients, we also identified the presence of so-called “low-density” neutrophils (LD-PMNs). These neutrophils, which are enriched in low-density fractions following centrifugation of blood over a density gradient, are reported in numerous disease states, including cancer, HIV, and systemic lupus erythematosus. In some disease states, LD-PMN are reported to be immunosuppressive toward T cell activation and proliferation. However, LD-PMNs from leishmaniasis patients showed no evidence of immunosuppression. Additionally, we found that LD-PMNs show significantly increased surface expression of MHC class II, suggesting a heretofore unappreciated connection between these atypical neutrophil phenotypes. We also investigated the in vitro interactions with different Leishmania infantum life-stages, both those that cause acute infection (promastigotes) and amastigotes, which are found during chronic stages of the disease. We found that PMNs are readily infected by all L. infantum life-stages, but that amastigotes may have different methods of interacting with PMN surface receptors and are better equipped to avoid PMN anti-microbial responses.
These data suggest that circulating PMNs in chronic leishmaniasis may have unique phenotypes and interact differently with the Leishmania spp. life-cycle present during chronic infection. Further investigation of the role of PMNs and atypical PMN phenotypes in chronic disease may help identify new immunomodulatory roles for this cell type.
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Hillegass, Melissa Ann. "SEX-BIASED PARASITISM AND THE REPRODUCTIVE COSTS OF PARASITES IN A SOCIAL AFRICAN GROUND SQUIRREL." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2205.
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Vertebrate males frequently carry higher numbers of parasites than females. This bias in parasite loads could be a consequence of sexual selection. Grouping species are also assumed to be afflicted with larger numbers of parasites than solitary animals and associated costs of this parasitism could vary with group size or structure. I examined sex-biased parasitism and the influence of group size on parasite loads in Cape ground squirrels (Xerus inauris), a highly social species that occurs in the arid regions of southern Africa. Males carried three times as many ectoparasites as females, but females harbored nearly three times more endoparasites than males. Amount of time spent (per hour) autogrooming was similar between males and females, but amount time spent allogrooming by adult female was over eleven times that of adult males. Longer allogrooming of group members could be decreasing the numbers of ectoparasites of group members and ultimately the group. Males infrequently give or receive allogrooming and travel in very large home ranges, potentially increasing their exposure to ectoparasites. However, movement throughout a large home range may result in males foraging in areas with lower densities of fecal pellets, which could explain the lower endoparasite loads observed in males. When I considered the age class of group members, female age classes were similarly parasitized but male age classes were not. Sub-adult males carried similar ectoparasite loads to adult males and similar endoparasite loads to adult females. This result is of particular interest because sub-adult males are becoming scrotal but typically remain in the group until adulthood. Sexual selection does appear to influence parasite loads in this species, and parasite removal or avoidance potentially mitigates individual parasite loads and their associated costs. Parasites can be detrimental to the health, longevity, and reproduction of their hosts, but these costs are rarely quantified. I removed ectoparasites and endoparasites from Cape ground squirrels for three months and evaluated changes in female body mass, reproduction, burrow use, and grooming in response to parasite removal. Female body mass did not increase with parasite removal, but reproductive success (per capita offspring raised to emergence) increased nearly four-fold, while allogrooming by treated females decreased. Since breeding is highest in the late winter dry season when fewer resources are available, the impact of parasites may be highest during this season. Lactation and gestation are the most physiological stressful processes that females undergo, and the dramatic increase in reproductive success in treated females suggests that these females are able to allocate more resources to reproduction than females afflicted with parasites. These results suggest that studies investigating reproduction and fecundity must consider the vulnerability of the host to parasite infection and the potential impact on reproductive success.M.S.
Department of Biology
Sciences
Biology MS
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Lagrue, Clement, and n/a. "Alternative life-history strategies in the trematode Coitocaecum parvum (Opecoelidae) : effects of environmental factors and within-host competition." University of Otago. Department of Zoology, 2008. http://adt.otago.ac.nz./public/adt-NZDU20080905.111744.
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From simple beginnings, when only one host was required, numerous parasitic organisms have evolved complex life-cycles involving two or more host species. For example, trematode parasites reproduce in vertebrates, their definitive host, but their current life cycle also typically involves two intermediate hosts that were added during the course of evolution. Vertebrates are often considered to be the ancestral hosts of trematodes although other scenarios exist. While multi-host life cycles are observed in distantly related groups of parasites, their evolution remains largely unexplored.
In trematodes, while recent phylogenetic studies have shed light on the sequence along which the different hosts were incorporated in the cycle, conditions that favoured the evolution of such complex life cycles can only be hypothesized. However, one opportunity to understand the force shaping the evolution of complex life cycles is provided by the few trematode species in which the classical three-host cycle facultatively reverts to a shorter cycle (i.e. life cycle abbreviation). In this study, the effects of different environmental factors on the life history strategy of the trematode Coitocaecum parvum were investigated using laboratory and field studies. C. parvum is able to abbreviate its life cycle from three to two hosts by maturing early (i.e. progenesis) and producing eggs inside the second intermediate host; both life history strategies occur simultaneously in C. parvum populations.
Environmental factors such as predator densities should strongly influence parasite life history strategies. In fact, this study shows that laboratory reared Coitocaecum parvum adopt preferentially the normal three-host cycle when chemical cues from the definitive host are added to their environment, while the shorter cycle is favoured when these cues are absent. However, in nature, multiple environmental factors are likely to be perceived by parasites. Consequently, C. parvum�s ability to adapt its developmental strategy to definitive host densities may be confounded by the complex combination of various environmental parameters.
Within-host competition between parasites sharing a common host is also likely to influence individual life history strategies. Parasites could then use alternative life strategies to adaptively respond to intraspecific and interspecific competition. Indeed, this study found that C. parvum preferentially adopts the abbreviated cycle in the presence of competitors. However, in interspecific competition, C. parvum�s strategy also depends upon the competitor species, possibly influenced by the other species� transmission route. Furthermore, intensity of intraspecific competition proved to constrain C. parvum�s ability to use the abbreviated life cycle. Finally, genetic relatedness between co-infecting C. parvum individuals seems to affect parasite life strategy through kin selection: closely related individuals are more likely to adopt the same developmental strategy, when they share a host, than unrelated ones.
C. parvum individuals adopting the abbreviated cycle are enclosed within a cyst in their intermediate host and must produce eggs by self-fertilization, the most severe case of inbreeding. It was hypothesized that their offspring would have reduced fitness due to inbreeding depression, therefore selecting against the shorter cycle. However, this study found no difference in the survival and infection success of offspring produced through the abbreviated and normal cycles. Furthermore, no evidence for a genetic basis of life cycle abbreviation was detected: the same proportion of offspring from both reproductive strategies adopted the shorter life cycle.
The work in this thesis provides evidence that although life cycle abbreviation provides Coitocaecum parvum with a viable alternative life strategy, numerous factors promote or restrict the adoption of this strategy. While this life history strategy has no detectable effect on parasite fitness, both environmental parameters and within-host competition affect C. parvum life-history strategies, alternatively selecting for either the shorter or normal life cycle. Overall, the complexity of the parasite environment could maintain both developmental strategies in C. parvum populations and, on a broader scale, could have influenced the evolution of complex life cycles in parasites.
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Kulma, Katarzyna. "Avian malaria, life-history trade-offs and interspecific competition in Ficedula flycatchers." Doctoral thesis, Uppsala universitet, Zooekologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-204349.
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This thesis investigates the impact of avian malaria (Haemosporidia) parasites on the outcome of interspecific competition between two closely related bird species, pied (Ficedula hypoleuca) and collared (F. albicollis) flycatchers. I further investigated how variation in timing of breeding, life history strategies and immune competence genes (MHC genes) modulate the fitness effects of malaria parasites in one of the two species i.e. collared flycatchers. Collared flycatchers colonized the Baltic island Öland in the late 1950-ties and has since then been expanding their breeding range while competitively excluding pied flycatchers from the favourable habitats (deciduous forests). I investigated the underlying mechanisms behind this exclusion by combining detailed long-term breeding data with modern molecular genetic techniques identifying both the presence/absence and lineage specificity of haemosporidian blood parasites. I found that the rapid decline of pied flycatchers can be explained by the combined effects of competition over nestling sites, hybridization and haemosporidian infections. Haemosporidian infections have a negative impact on survival of pied flycatcher females but no detectable effect on collared flycatchers’ longevity or reproductive success. This may be due to the fact that collared flycatchers carry (and are potentially exposed to) a higher diversity of parasites than pied flycatchers, which in turn may select for a higher diversity of MHC genes and hence a better overall protection from the negative impact of parasites. Indeed, functional MHC diversity correlates negatively with malaria prevalence among collared flycatchers from Gotland. Moreover, I found that both, malaria infection intensity and immunoglobulin level influences how infected collared flycatchers respond to increased nestling food-demands. The latter results mean that there is variation in allocation strategies (i.e. in resource allocation between reproductive effort and immune competence) within the collared flycatcher population. Hence, this population has the ability to respond to novel selection pressures in terms of optimal allocation of resources into immune functions. In summary, my results show that local parasites may facilitate the expansion of a new colonizer. This is important in the context of global climate change that will probably increase the colonization rate of southern species and lead to novel host-parasite interactions.
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Quigley, Benjamin J. Z. "The social lives of hosts and parasites." Thesis, University of Oxford, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.639732.
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All organisms are to some degree parasitised and display some form of social behaviour. Host and parasite social interactions are incredibly diverse and occur in all natural populations, therefore understanding such fundamental interactions is of profound importance - particularly from a public health perspective. The work in this thesis is developed in the context of bacteria and virus interactions, using the bacterium Pseudomonas fiourescens and bacteriophage SBW2502 for experiments. Mathematical models are developed in close conjunction with empirical data, with the aim of maintaining a high level of biological relevance of any theoretical undertakings. Chapter 1 demonstrates that selection on non-social traits can limit the invasion of social cheats. This is because beneficial mutations are most likely to arise in the numerically dominant cooperator population, and clonal sweeps would thus purge any genetic diversity. Chapter 2 is a theoretical development of chapter 1, which includes coevolution between hosts and parasites. The model governing the underlying host-parasite infection genetics (Matching Alleles; MA, Gene-for-Gene; GFG, or somewhere in between) has a big impact on the outcome of host social behaviour. Host cooperation is more favourable under a MA model, due to the more frequent switching of host genotypes, which acts to purge genetic diversity and re-establish homogenous cooperating host populations. Chapter 4 explores how host-parasite interactions shape the evolution of parasite diversity.
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Fleischmann, Tobias. "Deletion plastidärer ribosomaler Proteine in Nicotiana tabacum im Kontext reduktiver Genomevolutionund Entwicklung einer Hochdurchsatzplattform zur Analysevon miRNAs in Chlamydomonas reinhardtii." Phd thesis, Universität Potsdam, 2012. http://opus.kobv.de/ubp/volltexte/2012/6039/.
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Im Rahmen des ersten Teils der vorliegenden Doktorarbeit konnten zwei nicht-essentielle (rps15, rpl36) und fünf essentielle (rps3, rps16, rpl22, rpl23, rpl32) im Plastom von Nicotiana tabacum kodierte Proteine des plastidären Ribosoms bezüglich ihrer Essentialität charakterisiert werden. Diese Gene wurden durch gezielte Knockout-Experimente inaktiviert und die resultierenden Effekte untersucht.
Die Ergebnisse lassen einen Rückschluss auf die Lokalisation der Gene der insgesamt sieben untersuchten ribosomalen Proteine zu, die im Plastom mehrerer parasitischer, Plastiden-besitzender Spezies nicht mehr nachweisbar sind. Im Fall von rps15 könnte tatsächlich ein Verlust des Genes stattgefunden haben, im Fall der restlichen Gene ist eher mit einem Transfer in den Nukleus zu rechnen (rpl36 ausgenommen). Dies würde bedeuten, dass die Geschwindigkeit der erfolgreichen Etablierung eines Gentransfers in vielen parasitischen Spezies gegenüber grünen Pflanzen stark erhöht ist.
Alle in E. coli nicht-essentiellen Proteine mit Homologen in Plastiden (rps15, rpl33, rpl36) sind auch dort, trotz ~1,5 Milliarden Jahren getrennter Evolution, nicht essentiell. Dieses Ergebnis bestätigt den schon früher festgestellten hohen Konservierungsgrad der bakteriellen und plastidären Translationsmaschinerien.
Die Phänotypen der KO-Pflanzen der nicht-essentiellen Gene (rps15, rpl36) weisen auf eine interessante Rolle von S15 während der Ribosomenassemblierung hin und im Fall von L36 auf eine wichtige funktionelle Rolle im Plastiden-Ribosomen sowie auf eine Involvierung der Plastidentranslation in der Generierung eines retrograden Signals, welches die Blattform zu beeinflussen im Stande ist. Des Weiteren konnte eine Verbindung der Translationsaktivität mit der Ausbildung von Seitentrieben hergestellt werden, die vermutlich auf veränderte Auxinsynthese im Chloroplast zurückzuführen ist. Aus dem Folgeprojekt, bei dem Doppel-KO-Pflanzen nicht-essentieller ribosomaler Proteine erzeugt wurden, lässt sich auf eine relativ große Plastizität der Architektur von Plastidenribosomen schließen.
Im zweiten Teil der Arbeit konnte erfolgreich ein Hochdurchsatz-Screeningsystem zur semiquantitativen Analyse von 192 verschiedenen miRNAs aus Chlamydomonas reinhardtii etabliert werden. Es gelang durch die Untersuchung von 23 verschiedenen Wachstums- und Stressbedingungen sowie Entwicklungsstadien mehrere miRNAs zu identifizieren, die eine differenzielle Expression zeigen sowie unter allen untersuchten Bedingungen konstant bleibende miRNAs nachzuweisen. Dadurch konnten mehrere vielversprechende Kandidaten-miRNAs ausgemacht werden, die nun eingehender untersucht werden können.Plastid genomes of higher plants contain a conserved set of ribosomal protein genes. Although plastid translational activity is essential for cell survival in tobacco (Nicotiana tabacum), individual plastid ribosomal proteins can be nonessential. Candidates for nonessential plastid ribosomal proteins are ribosomal proteins identified as nonessential in bacteria and those whose genes were lost from the highly reduced plastid genomes of nonphotosynthetic plastid-bearing lineages (parasitic plants, apicomplexan protozoa). Here we report the reverse genetic analysis of seven plastid-encoded ribosomal proteins that meet these criteria. We have introduced knockout alleles for the corresponding genes into the tobacco plastid genome. Five of the targeted genes (ribosomal protein of the large subunit22 [rpl22], rpl23, rpl32, ribosomal protein of the small subunit3 [rps3], and rps16) were shown to be essential even under heterotrophic conditions, despite their loss in at least some parasitic plastid-bearing lineages. This suggests that nonphotosynthetic plastids show elevated rates of gene transfer to the nuclear genome. Knockout of two ribosomal protein genes, rps15 and rpl36, yielded homoplasmic transplastomic mutants, thus indicating nonessentiality. Whereas Δrps15 plants showed only a mild phenotype, Δrpl36 plants were severely impaired in photosynthesis and growth and, moreover, displayed greatly altered leaf morphology. This finding provides strong genetic evidence that chloroplast translational activity influences leaf development, presumably via a retrograde signaling pathway. In the second project a qRT-PCR based plattform for the analysis of miRNAs in Chlamydomonas reinhardtii has been developed. 20 different growth conditions have been scanned.
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Brooker, Adam Jonathan. "Aspects of the biology and behaviour of Lernaeocera branchialis (Linnaeus, 1767) (Copepoda: Pennellidae)." Thesis, University of Stirling, 2007. http://hdl.handle.net/1893/343.
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Lernaeocera branchialis (L., 1767) is a parasitic copepod that parasitises a range of gadoids by anchoring in the proximity of the branchial chamber of its host, deriving nutrition from the blood of its host and causing serious pathogenic effects. This study investigates the taxonomy of the juvenile free-swimming stages and host location behaviour in the pre-metamorphosed adult female. The large size and distinctive appearance of the metamorphosed adult female stage, coupled with the wide exploitation and commercial importance of one of its principle final gadoid hosts, the cod (Gadus morhua L.), means that this species has long been recognised in the scientific literature, and here the extensive literature concerning this potentially important and damaging pathogen is re-examined to provide an up to date overview, which includes both aquaculture and wild fisheries perspectives. Due to disagreements between several descriptions of the L. branchialis juvenile stages, and because the majority of the descriptions are over 60 years old, the juvenile free-swimming stages are re-described, using current terminology and a combination of both light and confocal microscopy. The time of hatching and moults in these stages is also examined. Techniques for the automated creation of taxonomic drawings from confocal images using computer software are investigated and the possibilities and implications of this technique are discussed. The method of host location in L. branchialis is unknown but is likely to involve a variety of mechanisms, possibly including chemo-reception, mechano-reception and the use of physical phenomena in the water column, such as haloclines and thermoclines, to search for fish hosts. In this study the role of host-associated chemical cues in host location by adult female L. branchialis is investigated by analysing the parasites behavioural responses to a range of host-derived cues, in both a choice chamber and a 3D tracking arena. To analyse the data from the experiments, specialised computer software (“Paratrack”) was developed to digitise the paths of the parasites’ movements, and calculate a variety of behavioural parameters, allowing behaviour patterns to be identified and compared. The results show that L. branchialis responds to host-associated chemical cues in a similar way to many copepods in the presence of chemical cues. Of the different cues tested, gadoid conditioned water appears to be most attractive to the parasites, although the wide variation in behavioural responses may indicate that other mechanisms are also required for host location. The different behavioural responses of parasites to whiting (Merlangius merlangus L.) and cod (Gadus morhua) conditioned water, which are both definitive hosts, provide some evidence for sub-speciation in L. branchialis. The role of chemical cues in host location of L. branchialis, and the relative importance of chemical and physical cues in host location are discussed. As well as demonstrating several techniques, which show potential for further development, this work has improved our knowledge of the biology and life-cycle of L. branchialis. Further study of this, and other areas of L. branchialis biology and its host-parasite interactions, should assist the development of contingency plans for the effective management and control of this widespread and potentially devastating pathogen.
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Prowse, Rhoda 1975. "The molecular basis for the resistance of Fasciola hepatica to cellular cytotoxicity." Monash University, Dept. of Biochemistry and Molecular Biology, 2003. http://arrow.monash.edu.au/hdl/1959.1/7714.
Full textBooks on the topic "Live parasites"
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Weir, Kirsten. Bugs that live on animals. New York: Marshall Cavendish Benchmark, 2009.
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Marrin, Albert. The creatures that live on us and in us. New York: Dutton Children's Books, 2011.
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ʻUtthā, Nirut. Nưng thotsawat kap kānphatthanā ngān khūapkhum rōk phayāt baimai tap sū nǣothāng kānprapplīan phrưttikam kānbō̜riphōk plā dip khō̜ng khon Thai ʻĪsān. [Khon Kaen, Thailand]: Samnakngān Sāthāranasuk Čhangwat Khō̜n Kǣn, 1998.
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Despommier, Dickson D., and John W. Karapelou. Parasite Life Cycles. New York, NY: Springer New York, 1988. http://dx.doi.org/10.1007/978-1-4612-3722-8.
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Brooks, D. R. Parascript: Parasites and the language of evolution. Washington: Smithsonian Institution Press, 1993.
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Olsen, O. Wilford. Animal parasites: Their life cycles and ecology. New York: Dover, 1986.
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Dixon, Richard C. Illustrated life cycles of common parasites in animals. Moscow, ID (5051C Old Pullman Rd., Moscow 83843): R.C. Dixon, 1987.
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National Geographic Society (U.S.), ed. Animal zombies!: And other bloodsucking beasts, creepy creatures, and real-life monsters. Washington, DC: National Geographic Society, 2018.
Find full textBook chapters on the topic "Live parasites"
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van Geest, Paul, Carlos J. B. de Bourbon de Parme, and Sylvester Eijffinger. "The Economy, Nature, and the Meaning of Life After the Coronavirus Crisis." In The New Common, 75–82. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-65355-2_11.
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Abstract“Christians still regularly tell you that nature is so beautiful and testifies of God’s greatness and goodness. Oh, dear people, nature is downright terrible, nature is one great suffering... What is ‘very good’ about a creation in which the most terrible parasites live in humans and animals...? What is ‘very good’ about a creation in which all organisms are terrorized by parasites, including parasites themselves?” (‘t Hart, Wie God verlaat heeft niets te vrezen. De Schrift betwist, pp. 7–8; 1997). The words by Maarten ‘t Hart seem irrefutable. Now that the coronavirus causes a disease that makes us realize that life is not as malleable in everything as we wish, they would have been almost prophetic if he had added the word “viruses” after “the most terrible parasites.”Long before Maarten ‘t Hart, ancient philosophers refused to accept the idea that creation is only cruel and chaotic.In this chapter, we will discuss how every crisis is an opportunity to continue to grow, either personally or collectively, or to come to a deeper understanding. Bearing this in mind, the question arises as to how we can learn from the present coronavirus crisis. How should society be rearranged? How should we deal with nature of which humankind is a part?
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Sithithaworn, Paiboon, Puangrat Yongvanit, Smarn Tesana, and Chawalit Pairojkul. "Liver Flukes." In World Class Parasites, 3–52. Boston, MA: Springer US, 2007. http://dx.doi.org/10.1007/978-0-387-71358-8_1.
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Tyler, K. M., C. L. Olson, and D. M. Engman. "The Life Cycle Of Trypanosoma Cruzi." In World Class Parasites, 1–11. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4419-9206-2_1.
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Strand, Michael R., and Miodrag Grbic’. "The Life History and Development of Polyembryonic Parasitoids." In Parasites and Pathogens, 37–56. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4615-5983-2_2.
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Williams, Ernest H., and Lucy Bunkley-Williams. "Life Cycle and Life History Strategies of Parasitic Crustacea." In Parasitic Crustacea, 179–266. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-17385-2_5.
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Despommier, Dickson D., and John W. Karapelou. "Protozoa." In Parasite Life Cycles, 1–39. New York, NY: Springer New York, 1987. http://dx.doi.org/10.1007/978-1-4612-3722-8_1.
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Despommier, Dickson D., and John W. Karapelou. "Cestoidea." In Parasite Life Cycles, 41–65. New York, NY: Springer New York, 1987. http://dx.doi.org/10.1007/978-1-4612-3722-8_2.
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Despommier, Dickson D., and John W. Karapelou. "Trematoda." In Parasite Life Cycles, 67–91. New York, NY: Springer New York, 1987. http://dx.doi.org/10.1007/978-1-4612-3722-8_3.
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Despommier, Dickson D., and John W. Karapelou. "Nematoda." In Parasite Life Cycles, 93–123. New York, NY: Springer New York, 1987. http://dx.doi.org/10.1007/978-1-4612-3722-8_4.
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Hawash, Yousry. "Parasitic Liver Diseases." In Liver Diseases, 161–72. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-24432-3_15.
Full textConference papers on the topic "Live parasites"
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Hussain, Nabiha, Hassan Alkhouri, and Shaden Haddad. "Preparation of live attenuated leishmania parasites by using laser technology." In TECHNOLOGIES AND MATERIALS FOR RENEWABLE ENERGY, ENVIRONMENT AND SUSTAINABILITY: TMREES18. Author(s), 2018. http://dx.doi.org/10.1063/1.5039163.
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Nogueira, Talita Pacheco, Rozineide Santana De Oliveira, Islaine Maria Aparecida Dos Santos Franceschi, Kédima Ferreira De Oliveira, and Rayane De Sousa Alves Castro. "INCIDÊNCIA DE ENTEROPARASITOSES EM ADULTOS NO BRASIL." In I Congresso Brasileiro de Parasitologia Humana On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/1962.
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Introdução: Parasitas intestinais é um dos maiores problema de saúde pública em todo o mundo e são responsáveis pela alta incidência de crianças. Essas infecções podem causar alterações nas condições físicas e sociais e afetar diretamente a qualidade de vida dos portadores, principalmente das crianças. Objetivo: Determinar os parasitas intestinais mais comuns em adultos. Material e métodos: Foram realizadas pesquisas bibliográficas, feitas a partir de arquivos do SciELO, dados da Biblioteca Virtual de Saúde (BVS), IBGE e PUBMED. Utilizou-se como estratégias de busca os seguintes descritores: “parasitose em adultos”, “parasitos intestinais”, para combinar os termos em questão usou-se o booleano “AND”. Foram incluídos artigos no idioma português, estudos epidemiológicos dos últimos 4 anos e de assunto central as parasitoses intestinais em adultos. Após análise criteriosa dos títulos e resumos, selecionaram-se 13 artigos. Resultados: Através das pesquisas, foi perceptível que depois da dengue, as diarreias (23,6%) e as verminoses (17,2%) são as mais frequentes em todo o território brasileiro. Aproximadamente 1 bilhão de pessoas em todo o mundo estão infectadas com pelo menos um parasita intestinal, dos quais a Ascaris lumbricoides (9,9%), o Trichuris Trichiura (4,8%) e os Ancilostomídeos (2,6%) apresentam as maiores prevalências. Vale ressaltar que os parasitas intestinais são um imenso problema de saúde pública no Brasil, principalmente porque o país está em desenvolvimento, pois são facilmente encontrados tanto em áreas rurais como urbanas, além de serem facilmente diagnosticados em humanos, principalmente em adultos com baixa escolaridade e com vulnerabilidade econômica prejudicada. Conclusão: As enteroparasitoses são os maiores colaboradores para graves quadros de desnutrição, diarreia, anemias e diminuição do desenvolvimento físico, principalmente em crianças/adolescentes, sendo a ascaridíase, tricuríase e ancilostomíase as mais graves e prejudiciais parasitoses intestinais. Essas doenças enteroparasitárias servem como indicadores das condições e desenvolvimento ambiental, social e econômico de uma vasta população.
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Apolinário, Joelma Maria dos Santos da Silva. "LARVA MIGRANS CUTÂNEA E SEU ACOMPANHAMENTO FARMACOTERAPÊUTICO." In II Congresso Brasileiro de Ciências Farmacêuticas On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/771.
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Introdução: A Larva migrans Cutânea (LMC) também denominada dermatite pruriginosa, apresenta características cosmopolita, ocorrendo com mais incidência em países tropicais e subtropicais. Seu diagnóstico é clínico baseando-se não pela sintomatologia do paciente acometido pelas lesões cutâneas oriundas do parasito em questão e também do prurido que o mesmo causa. Os principais agentes etiológicos são larvas de Ancylostoma braziliense e A. caninun parasitos do intestino delgado de cães de gatos, a patologia pode acontecer também por outros gêneros de parasitas, mas esses dois acima citados são os mais frequentes. Objetivo: Enfatizar a importância do acompanhamento farmacoterapêutico no que diz respeito a transmissibilidade da Larva migrans bem como a atuação dos parâmetros clínicos e farmacológicos dos pacientes afetados pelo parasita. Material e Métodos: Estudo de caso do tipo exploratório descritivo com abordagem qualitativa através da revisão sistemática da literatura que possibilitou a construção de referencial teórico sobre assuntos que estão relacionados ao tema em questão. Resultados: Na sintomatologia descrita pelos indivíduos acometidos por esse parasito as partes do corpo frequentemente atingidas são aquelas que entram em maior contato com o solo: pés, nádegas, mãos, pernas e raramente boca, o momento da penetração pode passar despercebido, ou muitas vezes pode causar prurido, eritema há também nas lesões mais antigas a formação de crostas deixando assim um caminho ou linha escura que posteriormente desaparece. Conclusão: Desse modo podemos afirmar que o acompanhamento farmacoterapêutico destinado para o tratamento da LMC teve reposta satisfatória, no que diz respeito a sintomatologia clínica dos pacientes afetados, uma vez que as drogas utilizadas são bem eficazes e o albendazol, que corresponde a uma das substâncias mais comumente utilizadas, tem eficácia de pelo menos 97% no tratamento destes pacientes acometidos pela parasitose, seguido do mebendazol, com eficácia de 86%.
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Souza, João Felipe dos Santos, Anderson Almeida Marques, Athauany Nogueira dos Santos, Jéssica Lourrany da Costa Carvalho, and Kelly Christiny Ribeiro de Sá. "INCIDÊNCIA DE ENTEROPARASITOSES EM CRIANÇAS NO BRASIL." In I Congresso Brasileiro de Parasitologia Humana On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/906.
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Introdução: Os parasitos intestinais por apresentarem um grande problema de saúde pública mundial, são responsáveis pelos altos índices de morbidade infantil. São infestações que podem desencadear alterações no estado físico e social, interferindo diretamente na qualidade de vida de seus portadores, principalmente em crianças. Objetivo: identificar as parasitoses intestinais mais prevalentes em crianças. Material e métodos: Foram realizadas pesquisas bibliográficas, feitas a partir de arquivos do SciELO, dados da Biblioteca Virtual de Saúde (BVS), IBGE e PUBMED. Utilizou-se como estratégias de busca os seguintes descritores: “parasitose em crianças”, “parasitos intestinais”, para combinar os termos em questão usou-se o booleano “AND”. Foram incluídos artigos no idioma português, estudos epidemiológicos dos últimos 5 anos e de assunto central as parasitoses intestinais em crianças. Após análise criteriosa dos títulos e resumos, selecionaram-se 11 artigos. Resultados: Evidencia-se que a diarreia (23,1%) e verminoses (17,2%), depois da dengue, foram as doenças mais frequentes nos municípios brasileiros. Cerca de um bilhão de pessoas no mundo estão infectadas por pelo menos um parasita intestinal, tendo com maior prevalência em crianças brasileiras, os Ascaris lumbricoides (10,3%), o Trichuris Trichiura (4,7%) e Ancilostomídeos (2,9%). É notável que enteroparasitoses são importantes problemas de saúde pública no Brasil, principalmente pelo país estar em desenvolvimento, uma vez que são diagnosticadas com bastante frequência nos seres humanos devido a facilidade de serem encontrados tanto em áreas rurais como urbanas, além de serem geograficamente fáceis de se propagarem. Conclusão: As enteroparasitoses colaboram para o agravamento de quadros de desnutrição, diarreia, anemias e diminuição do desenvolvimento físico, principalmente em crianças, na qual a ascaridíase, tricuríase e ancilostomíase são as principais parasitoses intestinais, respectivamente. Essas patologias enteroparasitárias servem como indicadores das condições e desenvolvimento ambiental, social e econômico de uma população.
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Meira, Roberta Rodrigues. "PASSEANDO PELA INTERAÇÃO PARASITAS - MICRORGANISMOS E HOSPEDEIRO." In I Congresso Brasileiro de Parasitologia Humana On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/686.
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Introdução: Parasitas e microrganismos se interagem, afirmando, num extremo, relações de cooperação recíproca, até relações conflituosas, na maioria das vezes patogênicas, no outro extremo. A coinfecção é de especial relevância porque as espécies de patógenos podem interagir no interior do hospedeiro, e as infecções decorrentes da interação ameaçam a saúde humana. Assim, é importante que as interações entre parasitas e microrganismos e deles com o hospedeiro e os seus mecanismos de defesa sejam estudados. Objetivo: Esta revisão tem como objetivo apresentar os dados científicos mais atuais sobre a interação molecular entre parasitas e microrganismos e as implicações desta sobre o hospedeiro. Material e métodos: Foi realizada uma busca na base de dados PubMed, Biblioteca Cochrane, Web of Science e Scopus, no período 2000 - 2020, utilizando os termos “interactions” “microorganisms”, “parasites”, “associations between parasites and microorganisms in humans” combinados entre si. Foram selecionados artigos de qualidade A das evidências. Foram incluídos estudos que abordassem interações entre parasitas e microrganismos no corpo humano, mas especialmente na pele, com ênfase em ácaros, bactérias e fungos, e doenças locais ou sistêmicas ocasionadas pela interação entre os mesmos. Resultados: Várias espécies de parasitas e microrganismos são conhecidos por serem patogênicos aos seres humanos. Tem sido observada regularmente associações potencialmente patogênicas entre parasitas e microrganismos, em um único hospedeiro. Vários modelos que abordam este problema forneceram previsões sobre como a associação e o conflito entre parasitas e microrganismos podem desencadear infecções múltiplas, que podem ter consequências gravíssimas se não forem tratadas adequadamente. Entretanto, ainda pouco se sabe sobre esse tipo de interação e, especialmente o seu impacto patogênico, especialmente na pele do hospedeiro humano. Conclusão: Portanto, uma melhor compreensão dos mecanismos responsáveis pela interação entre parasitas e microrganismos e deles com o hospedeiro pode contribuir para o desenvolvimento de alternativas terapêuticas direcionadas exclusivamente ao tratamento de doenças decorrentes de interações, cada vez mais difíceis de tratar, aliviando assim o transtorno da falta de medicamentos específicos e também da resistência antimicrobiana cada vez maior.
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Napoli, Andréia Lívia Gonzalez, and Allan Eurípedes Rezende Napoli. "SÍNDROME DE LOEFFLER: DIAGNÓSTICO E CICLO BIOLÓGICO DO PRINCIPAL PARASITA INTESTINAL CAUSADOR DA SÍNDROME." In I Congresso Brasileiro de Parasitologia Humana On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/712.
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Introdução: A alta prevalência das parasitoses no Brasil deve-se as condições sócioeconômicas precárias da maioria da população. A Síndrome de Loeffler é caracterizada por uma pneumonia eosinofílica, causada por parasitas intestinais com ciclo pulmonar obrigatório na qual evidencia-se infiltrado pulmonar migratório na radiografia de tórax e eosinofilia detectada no hemograma, em pacientes com tosse seca, dispnéia, sibilos e febre baixa. Objetivo: O estudo teve como objetivo buscar na literatura os aspectos clínicos, parasitológicos e o desenvolvimento da Síndrome de Loeffler, dada a alta prevalência destas parasitoses no Brasil. Materiais e métodos: Trata-se de uma revisão bibliográfica de artigos em inglês, espanhol e português, extraídos das bases de dados MEDLINE, PUBMED e Google Acadêmico. Os descritores utilizados foram "Síndrome de Loeffler” AND “pneumonia eosinofílica” AND “parasitose intestinal", Resultados: A Síndrome de Loeffler representa uma pneumonite eosinofílica transitória causada, principalmente, pelos helmintos: Necator americanus, Ancylostoma duodenale, Strongyloides stercoralis e Ascaris lumbricoides, destacando-se o último. Especificamente, o contágio do Ascaris inicia-se com a ingestão de ovos de vermes encontrados em água e alimentos contaminados. No intestino delgado, os ovos eclodem em larvas que penetram a parede do intestino e migram via circulação porta até o fígado e, em seguida, via circulação sistêmica até os pulmões. As larvas introduzem nas paredes alveolares, deslocam-se até a garganta e são deglutidas. Posteriormente, retornam ao intestino e se transformam em vermes adultos, iniciando a reprodução, reiniciando o processo. Outrossim, o desenvolvimento da infecção pelos parasitas dura cerca de 2 a 6 semanas e os sintomas, quando presentes, iniciam-se após 7 a 14 dias do contágio. O diagnóstico da Síndrome de Loeffler é realizado por uma avaliação clínica, na qual pode-se observar sintomas respiratórios característicos, achados radiológicos de tórax, mostrando um infiltrado alvéolo-intersticial de caráter migratório, e, laboratorialmente, a síndrome é caracterizada por eosinofilia sanguínea. Conclusão: Para um adequado diagnóstico da Síndrome de Loeffler, é necessário associar à uma anamnese detalhada dados radiológicos e laboratoriais, acarretando assim em uma correta e precoce investigação do caso. Ademais, medidas sanitárias são importantes para reduzir a alta prevalência das parasitoses no Brasil.
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Silva, Arthur De Morais, João Victor Araujo Acioli, Kátia Karine Araujo Acioli, Maria Gabriella Pedrosa Carvalho, and Weyla Carla Souza. "COMPLICAÇÕES EM PACIENTES COM ENTEROBÍASE." In I Congresso Brasileiro de Parasitologia Humana On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/754.
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Introdução: A enterobíase, também chamada de oxiuríase, é uma parasitose causada pelo helminto Enterobius Vermicularis. É uma zoonose de transmissão predominantemente fecal-oral, por isso, é muito típica em pacientes pediátricos. O paciente normalmente é assintomático, ou cursa com sintomas leves, dos quais, um muito frequente é o prurido perianal, principalmente à noite. O paciente que não tem o tratamento de maneira eficaz e/ou rápida, tende a cursar com piora, apresentando complicações, como: infecções secundárias, causadas pelas lesões na região perianal, provocadas quando o paciente coça, causando um quadro inflamatório devido ao estresse oxidativo, e consequentemente, petéquias. Nestas, ficam as fêmeas adultas e os ovos. Alguns pacientes apresentam sintomas gastrointestinais, como êmese frequente, diarreia e/ou disenteria, dor abdominal sem local específico, tenesmo, e esses são relacionados com a carga de parasitas que estão no corpo do paciente. O parasita pode se deslocar para outras regiões, como a vulva e a vagina, causando vulvovaginite pelo estresse oxidativo gerado, para as trompas, causando salpingite, a qual pode complicar, gerando abscesso tubo-ovariano, que tipicamente deixa a paciente infértil. Objetivo: Identificar as principais complicações que ocorrem em pacientes com enterobíase. Material e métodos: Revisão integrativa de literatura, com busca de artigos científicos no MINISTÉRIO DA SAÚDE, e SCIELO. Os critérios utilizados para inclusão foram: artigos originais, na língua portuguesa, e dos últimos 5 anos. Resultados: Foram encontrados nas bases de dados 6 artigos coerentes com as complicações dos pacientes com enterobíase. Segundo a pesquisa realizada, foi visto que os pacientes que não realizam o tratamento no estágio inicial têm maiores chances de complicações, principalmente no aparelho reprodutor feminino, causando graves consequências no estilo de vida da paciente. Algumas outras complicações, como ruptura intestinal, causada pelo parasitas, enterite, estresse oxidativo acentuado, podem fazer com que o paciente tenha seu estado de saúde agravado. Conclusão: Assim, conhecer e entender as complicações da enterobíase, pode ajudar a criar meios para que a saúde do paciente melhore, e evitar consequências irreversíveis.
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Matias, Maria Da Glória De Lima, Edivan Lourenço Da Silva Júnior, Thaís Arielly Firmino De Souza Silva, Deise Ayara De Lyra Pereira, and Gleyka Dais De Melo Santos. "A LEISHMANIA TEGUMENTAR AMERICANA E A AÇÃO DO PARASITA NO SISTEMA IMUNE." In I Congresso Brasileiro de Imunologia On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/963.
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Introdução: A Leishmaniose tegumentar é uma doença parasitária, crônica e infecciosa, sendo uma das principais doenças negligenciadas. É caracterizada pela infecção ativa do protozoário do gênero Leishmania, caracterizada pelo desenvolvimento de lesões cutâneas, que podem produzir úlceras e deixar cicatrizes, gerando danos físicos e emocionais nos indivíduos infectados. Por sua fácil transmissão, que se dá através de insetos hematófagos, flebotomíneos, é importante o estudo das formas de ação do parasita no organismo humano, visando-se formas de tratamento mais eficientes, já que a doença atinge muitos indivíduos nas regiões endêmicas e não existem muitas alternativas para o tratamento. Objetivo: Analisar a infecção do parasita do gênero Leishmania no organismo e sua respectiva ação no sistema imune. Metodologia: Realizou-se uma pesquisa bibliográfica nas bases de dados científicos Scielo, PubMed, LILACS e Google Acadêmico, considerou-se publicações de artigos científicos dos últimos cinco anos. Resultados e discussão: O ciclo evolutivo da Leishmania apresenta duas formas: promastigota, encontrada no vetor, e amastigota, forma intracelular presente nos hospedeiros. Os glicanos, polissacarídeos, possuem importante papel durante o processo infeccioso, os glicoconjugados como glicoinositolfosfolipídios e proteofosfoglicanos tipo mucina estão envolvidos nas primeiras linhas de infecção por macrófagos. Já as glicoproteínas ancoradas por sitol exercem funções essenciais na interação parasita-hospedeiro. A metaloprotease modula uma ampla via de sinalização das células hospedeiras, facilita o escape do parasita da lise e inibe a resposta das células Natural Killers, protegendo os parasitas intracelulares. Outros fatores importantes no processo infeccioso são a proteína PSA-2, envolvida na ligação e invasão dos parasitas em macrófagos e o ácido siálico, utilizados pela Leishmania para estabelecer ligações com os receptores da membrana, presentes nas células hematopoiéticas, promovendo sua entrada nos macrófagos. Conclusão: A compreensão destas interações entre parasita e hospedeiro durante e após o processo infeccioso é importante para ter uma visão de como os protozoários implementam a infecção no organismo e burlam a resposta imune do hospedeiro. Desta forma, novos medicamentos que sejam direcionados a estes fatores, seriam fundamentais para a melhoria da eficácia, segurança do tratamento e diminuição dos riscos de resistência aos medicamentos, com a redução dos riscos de consequências nocivas advindas desta enfermidade.
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Júnior, Benílton Alves Rodrigues, Débora Pereira Gomes Prado, Hanstter Hallison Alves Rezende, and Andressa Rodrigues Lopes. "A DETERMINAÇÃO DE GIARDIA SP. E CRYPTOSPORIDIUM SP. EM ÁGUA E RELEVÂNCIA: REVISÃO DE LITERATURA." In II Congresso Brasileiro de Saúde On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/1528.
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Introdução: A Giardia spp. é um protozoário que causa infecções intestinais, a giardiose. O parasita é transmitido pela água ou alimentos contaminados, com seu índice de acometimento relacionado a falta de saneamento básico. O Cryptosporidium spp. é o protozoário causador da criptosporidiose, que acomete animais e humanos, sendo que seu principal veículo de transmissão é a água contaminada. Os sintomas dessas parasitoses são diarreia e cólicas abdominais. Menos frequentes são enjoo, vômito, febre e fraqueza. Objetivo: Enunciar metodologias aplicadas na determinação de Giardia spp. e Cryptosporidium spp. em amostras de água e relatar a relevância desta determinação para a saúde humana. Metodologia: Trata-se de um estudo de revisão literária narrativa, no intervalo de tempo de 2011-2021, onde utilizou-se das plataformas online Google Acadêmico e Portal de periódicos CAPES/MEC, com os seguintes descritores: determinação de Giardia spp. e Cryptosporidium spp em água e qualidade da água. Resultados e discussão: A análise parasitológica de Giardia spp. e Cryptosporidium spp. na água destinada ao abastecimento é de grande importância devido aos riscos para saúde pública. A determinação desses parasitas podem ser realizadas em diversas metodologias, sendo mais utilizada mundialmente o método 1623 proposto pela Agência de Proteção Ambiental dos Estados Unidos (USEPA), que inclui fases de concentração, separação imunomagnéticas e microscopia de imunofluorescência. Entretanto, outras metodologias também são utilizadas, como a centrifugação e leitura direta em microscópio de luz, métodos de coloração convencionais, filtração em membrana, raspagem, dissolução e floculação, além de técnicas moleculares, como PCR e Nested-PCR. Sendo que destas metodologias, o método de filtração em membranas apresenta melhor custo-benefício, pois é resistente ao cloro e promove a determinação das espécies parasitarias visto que não é possível realizar tal ação através de metodologias convencionais. Conclusão: As doenças relacionadas à contaminação hídrica é um grande problema de saúde pública no mundo, logo que a má qualidade da água resulta em uma baixa qualidade de vida e a contaminação por Giardia spp. e Cryptosporidium spp. um risco a saúde humana, contudo, a determinação precisa de tais parasitas é de uma importância extrema para que haja uma total eliminação na água distribuída à população.
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Xavier, Gabriela Reis, Gustavo De Oliveira Alves Pinto, Ivina De Almeida Freitas, and Miriam Nogueira Teixeira. "EFUSÃO PLEURAL EM CÃES COM SÍNDROME DA VEIA CAVA PARASITADOS POR DIROFILARIA IMMITIS." In I Congresso On-line Nacional de Clínica Veterinária de Pequenos Animais. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/1842.
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Introdução: A dirofilariose é uma doença parasitária causada pelo agente etiológico Dirofilaria immitis, que tem como hospedeiro final os cães que são infectados após a picadura de vetores, sendo estes os mosquitos dos gêneros Aedes, Anopheles e Culex. Esse parasito é potencialmente fatal, pois os vermes possuem afinidade pelas artérias pulmonares, causando doença cardiorrespiratória grave nos animais. A presença desses parasitos no coração direito leva a insuficiência cardíaca direita, ocasionando os típicos sinais clínicos de dispneia, tosse, fadiga, perda de peso e intolerância ao esforço físico. As alterações vasculares evoluem de acordo com carga parasitária, no qual é iniciado as manifestações mais graves da doença, desenvolvendo a síndrome da veia cava e, por consequência, o aparecimento da efusão pleural. Objetivo: Correlacionar a presença dos vermes nas artérias pulmonares com o desenvolvimento da síndrome da veia cava e o mecanismo de formação da efusão pleural. Materiais e métodos: A Realização da pesquisa foi desenvolvida com base em literaturas e em plataformas cientificas como Pubvet®, SciELO e Google Acadêmico (Scholar), utilizando os seguintes descritores: dirofilariose, síndrome da veia cava e efusões pleurais. Resultados: A pesquisa demonstrou que cães portadores de dirofilariose desenvolvem a síndrome clínica conforme a sua carga parasitária. A alta carga parasitária estimula o desenvolvimento da síndrome da veia cava, causada pelo movimento retrógado dos parasitos, obstruindo o fluxo sanguíneo para o coração direito e regurgitação da tricúspide diminuindo o retorno venoso. O retorno sanguíneo aumenta a pressão sanguínea da veia cava tendenciando a saída do líquido do meio intravascular para o meio extravascular, ocasionando o acúmulo do líquido na cavidade pleural. Além da efusão pleural, pode haver congestão hepática e ascite. A efusão pleural resulta nos sinais clínicos de taquipneia ou dispneia, dificultando a hematose, consequentemente causando hipóxia, sendo a causa mortis em diversos casos. Conclusão: É importante elucidar a relação entre o surgimento da síndrome da veia cava, da formação de efusões cavitarias e da parasitose por Dirofilária immitis, a fim de facilitar e direcionar o tratamento, manejo e prevenção devido seu grande potencial fatal nas populações de caninos.
Reports on the topic "Live parasites"
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Charissa de Bekker, Charissa de Bekker. How does a parasite create zombie-like behavior? Experiment, October 2013. http://dx.doi.org/10.18258/1490.
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Barrett, Patrick. "Like a Parasite Dozing in the Gut": Idleness and Tending in J.M. Coetzee's Life and Times of Michael K. Portland State University Library, January 2016. http://dx.doi.org/10.15760/honors.278.
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Prachumsri, Jetsumon. Proteomic Study of Human Malaria Parasite Plasmodium Vivax Liver Stages for Development of Vaccines and Drugs. Fort Belvoir, VA: Defense Technical Information Center, October 2008. http://dx.doi.org/10.21236/ada494445.
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