| native larvivorous fish in an endemic malarious area of southern iran, a biological alternative factor for chemical larvicides in malaria control program. | the widespread use of chemical insecticides, resistance in vectors and environmental problems, all have led to an increased interest in the use of biological agents in malaria control programs. the most important functional elements are the native fish. the aim of this study was to identify the native species of lavivorous fish in rudan county, southern iran, to introduce an effective species and to propose its' implementation in the national malaria control program. | 0 | 26744713 |
| identification of host-plant volatiles and characterization of two novel general odorant-binding proteins from the legume pod borer, maruca vitrata fabricius (lepidoptera: crambidae). | chemoreception is a key feature in selection of host plant by phytophagous insects, and odorant-binding proteins (obps) are involved in chemical communication of both insects and vertebrates. the legume pod borer, maruca vitrata fabricius (lepidoptera: crambidae) is one of the key pest species of cowpea and widely distributed throughout tropical and subtropical regions, causing up to 80% of yield loss. in this study, we investigated the electrophysiological responses of female m. vitrata to flor ... | 2015 | 26517714 |
| co-expression of interleukin-15 enhances the protective immune responses induced by immunization with a murine malaria mva-based vaccine encoding the circumsporozoite protein. | malaria remains a major global public health problem with an estimated 200 million cases detected in 2012. although the most advanced candidate malaria vaccine (rts,s) has shown promise in clinical trials, its modest efficacy and durability have created uncertainty about the impact of rts,s immunization (when used alone) on global malaria transmission. here we describe the development and characterization of a novel modified vaccinia virus ankara (mva)-based malaria vaccine which co-expresses th ... | 2015 | 26505634 |
| increases in both temperature means and extremes likely facilitate invasive herbivore outbreaks. | although increases in mean temperature (mt) and extreme high temperature (eht) can greatly affect population dynamics of insects under global warming, how concurrent changes in both mt and eht affect invasive species is largely unknown. we used four thermal regimes to simulate the increases in summer temperature and compared their effects on the life-history traits of three geographical populations (chongqing, wuhan and shanghai) of an invasive insect, corythucha ciliata, in china. the four ther ... | 2015 | 26502826 |
| impact of environmental variation on host performance differs with pathogen identity: implications for host-pathogen interactions in a changing climate. | specialist and generalist pathogens may exert different costs on their hosts; thereby altering the way hosts cope with environmental variation. we examined how pathogen-challenge alters the environmental conditions that maximize host performance by simultaneously varying temperature and nutrition (protein to carbohydrate ratio; p:c) after exposure to two baculoviruses; one that is specific to the cabbage looper, trichoplusia ni (tnsnpv) and another that has a broad host range (acmnpv). virus-cha ... | 2015 | 26477393 |
| overexpression of a triticum aestivum calreticulin gene (tacrt1) improves salinity tolerance in tobacco. | calreticulin (crt) is a highly conserved and abundant multifunctional protein that is encoded by a small gene family and is often associated with abiotic/biotic stress responses in plants. however, the roles played by this protein in salt stress responses in wheat (triticum aestivum) remain obscure. in this study, three tacrt genes were identified in wheat and named tacrt1, tacrt2 and tacrt3-1 based on their sequence characteristics and their high homology to other known crt genes. quantitative ... | 2015 | 26469859 |
| population-based seroprevalence of malaria in hormozgan province, southeastern iran: a low transmission area. | the seroepidemiological condition of malaria in three main districts of hormozgan province, a low transmission area in southeast of iran, was investigated. methods. sera samples (803) were collected from healthy volunteers from the three main districts (bandar lengeh in the west, bandar abbas in the center, and bandar jask in the east) of hormozgan province. a questionnaire was used to record the sociodemographic features of the participants during sample collecting. an in-house elisa test, usin ... | 2015 | 26543662 |
| bioprotective role of yeasts. | the yeasts constitute a large group of microorganisms characterized by the ability to grow and survive in different and stressful conditions and then to colonize a wide range of environmental and human ecosystems. the competitive traits against other microorganisms have attracted increasing attention from scientists, who proposed their successful application as bioprotective agents in the agricultural, food and medical sectors. these antagonistic activities rely on the competition for nutrients, ... | 2015 | 27682107 |
| evaluation of antiplasmodial activity of extracts and constituents from ampelozizyphus amazonicus. | ampelozizyphus amazonicus ducke, a plant that is widely used by the population of the amazonian region to prevent and treat malaria, was investigated in this work, which describes, for the first time, the antiplasmodial activity of its extracts and associates this activity with its isolated constituents. | 0 | 26664012 |
| global transcriptional repression: an initial and essential step for plasmodium sexual development. | gametocytes are nonreplicative sexual forms that mediate malaria transmission to a mosquito vector. they are generated from asexual blood-stage parasites that proliferate in the circulation. however, little is known about how this transition is genetically regulated. here, we report that an apetala2 (ap2) family transcription factor, ap2-g2, regulates this transition as a transcriptional repressor. disruption of ap2-g2 in the rodent malaria parasite plasmodium berghei did not prevent commitment ... | 2015 | 26417110 |
| the potential for fungal biopesticides to reduce malaria transmission under diverse environmental conditions. | the effectiveness of conventional malaria vector control is being threatened by the spread of insecticide resistance. one promising alternative to chemicals is the use of naturally-occurring insect-killing fungi. numerous laboratory studies have shown that isolates of fungal pathogens such as beauveria bassiana can infect and kill adult mosquitoes, including those resistant to chemical insecticides.unlike chemical insecticides, fungi may take up to a week or more to kill mosquitoes following exp ... | 2015 | 26792946 |
| roles of nlaktip in the growth and eclosion of the rice brown planthopper, nilaparvata lugens stål, as revealed by rna interference. | akt-interacting protein (aktip) interacts with serine/threonine protein kinase b (pkb)/akt. aktip modulates akt's activity by enhancing the phosphorylation of the regulatory site and plays a crucial role in multiple biological processes. in this study, the full length cdna of nlaktip, a novel aktip gene in the brown planthopper (bph) nilaparvata lugens, was cloned. the reverse transcription quantitive pcr (rt-qpcr) results showed that the nlaktip gene was strongly expressed in gravid female adul ... | 2015 | 26402675 |
| recurrent domestication by lepidoptera of genes from their parasites mediated by bracoviruses. | bracoviruses are symbiotic viruses associated with tens of thousands of species of parasitic wasps that develop within the body of lepidopteran hosts and that collectively parasitize caterpillars of virtually every lepidopteran species. viral particles are produced in the wasp ovaries and injected into host larvae with the wasp eggs. once in the host body, the viral dna circles enclosed in the particles integrate into lepidopteran host cell dna. here we show that bracovirus dna sequences have be ... | 2015 | 26379286 |
| rhodnius prolixus life history outcomes differ when infected with different trypanosoma cruzi i strains. | the effect of a parasite on the life history of its vector is important for understanding and predicting disease transmission. chagas disease agent trypanosoma cruzi is a generalist parasite that is diverse across scales from its genetic diversity to the 100s of mammal and vector species it infects. its vertebrate hosts show quite variable responses to infection, however, to date there are no studies looking at how t. cruzi variability might result in variable outcomes in its invertebrate host. ... | 2015 | 26078316 |
| a new set of chemical starting points with plasmodium falciparum transmission-blocking potential for antimalarial drug discovery. | the discovery of new antimalarials with transmission blocking activity remains a key issue in efforts to control malaria and eventually eradicate the disease. recently, high-throughput screening (hts) assays have been successfully applied to plasmodium falciparum asexual stages to screen millions of compounds, with the identification of thousands of new active molecules, some of which are already in clinical phases. the same approach has now been applied to identify compounds that are active aga ... | 2015 | 26317851 |
| evaluation of the impact of codon optimization and n-linked glycosylation on functional immunogenicity of pfs25 dna vaccines delivered by in vivo electroporation in preclinical studies in mice. | plasmodium falciparum sexual stage surface antigen pfs25 is a well-established candidate for malaria transmission-blocking vaccine development. immunization with dna vaccines encoding pfs25 has been shown to elicit potent antibody responses in mice and nonhuman primates. studies aimed at further optimization have revealed improved immunogenicity through the application of in vivo electroporation and by using a heterologous prime-boost approach. the goal of the studies reported here was to system ... | 2015 | 26135972 |
| cd68 acts as a major gateway for malaria sporozoite liver infection. | after being delivered by the bite from an infected mosquito, plasmodium sporozoites enter the blood circulation and infect the liver. previous evidence suggests that kupffer cells, a macrophage-like component of the liver blood vessel lining, are traversed by sporozoites to initiate liver invasion. however, the molecular determinants of sporozoite-kupffer cell interactions are unknown. understanding the molecular basis for this specific recognition may lead to novel therapeutic strategies to con ... | 2015 | 26216124 |
| plasmodium berghei mapk1 displays differential and dynamic subcellular localizations during liver stage development. | mitogen-activated protein kinases (mapks) regulate key signaling events in eukaryotic cells. in the genomes of protozoan plasmodium parasites, the causative agents of malaria, two genes encoding kinases with significant homology to other eukaryotic mapks have been identified (mapk1, mapk2). in this work, we show that both genes are transcribed during plasmodium berghei liver stage development, and analyze expression and subcellular localization of the pbmapk1 protein in liver stage parasites. li ... | 2013 | 23544094 |
| quinolone-3-diarylethers: a new class of antimalarial drug. | the goal for developing new antimalarial drugs is to find a molecule that can target multiple stages of the parasite's life cycle, thus impacting prevention, treatment, and transmission of the disease. the 4(1h)-quinolone-3-diarylethers are selective potent inhibitors of the parasite's mitochondrial cytochrome bc1 complex. these compounds are highly active against the human malaria parasites plasmodium falciparum and plasmodium vivax. they target both the liver and blood stages of the parasite a ... | 0 | 23515079 |
| dedicated olfactory neurons mediating attraction behavior to ammonia and amines in drosophila. | animals across various phyla exhibit odor-evoked innate attraction behavior that is developmentally programmed. the mechanism underlying such behavior remains unclear because the odorants that elicit robust attraction responses and the neuronal circuits that mediate this behavior have not been identified. here, we describe a functionally segregated population of olfactory sensory neurons (osns) and projection neurons (pns) in drosophila melanogaster that are highly specific to ammonia and amines ... | 2013 | 23509267 |
| plasmodium yoelii inhibitor of cysteine proteases is exported to exomembrane structures and interacts with yoelipain-2 during asexual blood-stage development. | plasmodium falciparum (pf) blood stages express falstatin, an inhibitor of cysteine proteases (icp), which is implicated in regulating proteolysis during red blood cell infection. recent data using the plasmodium berghei rodent malaria model suggested an additional role for icp in the infection of hepatocytes by sporozoites and during liver-stage development. here we further characterize the role of icp in vivo during infection with plasmodium yoelii (py) and pf. we found that py-icp was refract ... | 2013 | 23421981 |
| next-generation site-directed transgenesis in the malaria vector mosquito anopheles gambiae: self-docking strains expressing germline-specific phic31 integrase. | diseases transmitted by mosquitoes have a devastating impact on global health and the situation is complicated due to difficulties with both existing control measures and the impact of climate change. genetically modified mosquitoes that are refractory to disease transmission are seen as having great potential in the delivery of novel control strategies. the streptomyces phage phic31 integrase system has been successfully adapted for site-directed transgene integration in a range of insects, thu ... | 2013 | 23516619 |
| homologs of vertebrate opn3 potentially serve as a light sensor in nonphotoreceptive tissue. | most opsins selectively bind 11-cis retinal as a chromophore to form a photosensitive pigment, which underlies various physiological functions, such as vision and circadian photoentrainment. recently, opsin 3 (opn3), originally called encephalopsin or panopsin, and its homologs were identified in various tissues including brain, eye, and liver in both vertebrates and invertebrates, including human. because opn3s are mainly expressed in tissues that are not considered to contain sufficient amount ... | 2013 | 23479626 |
| effects of fluctuating daily temperatures at critical thermal extremes on aedes aegypti life-history traits. | the effect of temperature on insect biology is well understood under constant temperature conditions, but less so under more natural, fluctuating conditions. a fluctuating temperature profile around a mean of 26°c can alter aedes aegypti vector competence for dengue viruses as well as numerous life-history traits, however, the effect of fluctuations on mosquitoes at critical thermal limits is unknown. | 2013 | 23520534 |
| qualification of standard membrane-feeding assay with plasmodium falciparum malaria and potential improvements for future assays. | vaccines that interrupt malaria transmission are of increasing interest and a robust functional assay to measure this activity would promote their development by providing a biologically relevant means of evaluating potential vaccine candidates. therefore, we aimed to qualify the standard membrane-feeding assay (smfa). the assay measures the transmission-blocking activity of antibodies by feeding cultured p. falciparum gametocytes to anopheles mosquitoes in the presence of the test antibodies an ... | 2013 | 23483940 |
| characterizing microclimate in urban malaria transmission settings: a case study from chennai, india. | environmental temperature is an important driver of malaria transmission dynamics. both the parasite and vector are sensitive to mean ambient temperatures and daily temperature variation. to understand transmission ecology, therefore, it is important to determine the range of microclimatic temperatures experienced by malaria vectors in the field. | 2013 | 23452620 |
| the plasmodium berghei ca(2+)/h(+) exchanger, pbcax, is essential for tolerance to environmental ca(2+) during sexual development. | ca(2+) contributes to a myriad of important cellular processes in all organisms, including the apicomplexans, plasmodium and toxoplasma. due to its varied and essential roles, free ca(2+) is tightly regulated by complex mechanisms. these mechanisms are therefore of interest as putative drug targets. one pathway in ca(2+) homeostatic control in apicomplexans uses a ca(2+)/h(+) exchanger (a member of the cation exchanger family, cax). the p. falciparum cax (pfcax) has recently been characterised i ... | 2013 | 23468629 |
| perturbations of plasmodium puf2 expression and rna-seq of puf2-deficient sporozoites reveal a critical role in maintaining rna homeostasis and parasite transmissibility. | malaria's cycle of infection requires parasite transmission between a mosquito vector and a mammalian host. we here demonstrate that the plasmodium yoelii pumilio-fbf family member puf2 allows the sporozoite to remain infectious in the mosquito salivary glands while awaiting transmission. puf2 mediates this solely through its rna-binding domain (rbd) likely by stabilizing or hastening the degradation of specific mrnas. puf2 traffics to sporozoite cytosolic granules, which are negative for severa ... | 2013 | 23356439 |
| expression profile of the plasmodium falciparum intra-erythrocytic stage protein, pf3d7_1363700. | efforts to control malaria are demanding due to drug-resistant parasites, insecticide-resistant mosquitoes and poor health infrastructure in malaria-endemic countries. therefore, the research and development of additional malaria control methods are crucial. for host-parasite interactions, surface antigens and secreted proteins are likely to be involved in infectivity and invasion of host tissues and therefore can be effective targets for control by vaccines, drug therapy, or novel mosquito cont ... | 2013 | 23418676 |
| the role of reactive oxygen species in anopheles aquasalis response to plasmodium vivax infection. | malaria affects millions of people worldwide and hundreds of thousands of people each year in brazil. the mosquito anopheles aquasalis is an important vector of plasmodium vivax, the main human malaria parasite in the americas. reactive oxygen species (ros) have been shown to have a role in insect innate immune responses as a potent pathogen-killing agent. we investigated the mechanisms of free radicals modulation after a. aquasalis infection with p. vivax. ros metabolism was evaluated in the ve ... | 2013 | 23441231 |
| a cell-based screening platform identifies novel mosquitocidal toxins. | pesticides currently in widespread use often lack species specificity and also become less effective as resistance emerges. consequently, there is a pressing need to develop novel agents that are narrowly targeted and safe to humans. a cell-based screening platform was designed to discover compounds that are lethal to mosquito (anopheles and aedes) cells but show little or no activity against other insect (drosophila) or human cell lines. mosquito-specific, aqueous-stable cytotoxins were recover ... | 2013 | 23407365 |
| costs of crowding for the transmission of malaria parasites. | the utility of using evolutionary and ecological frameworks to understand the dynamics of infectious diseases is gaining increasing recognition. however, integrating evolutionary ecology and infectious disease epidemiology is challenging because within-host dynamics can have counterintuitive consequences for between-host transmission, especially for vector-borne parasites. a major obstacle to linking within- and between-host processes is that the drivers of the relationships between the density, ... | 2013 | 23789029 |
| features of autophagic cell death in plasmodium liver-stage parasites. | analyzing molecular determinants of plasmodium parasite cell death is a promising approach for exploring new avenues in the fight against malaria. three major forms of cell death (apoptosis, necrosis and autophagic cell death) have been described in multicellular organisms but which cell death processes exist in protozoa is still a matter of debate. here we suggest that all three types of cell death occur in plasmodium liver-stage parasites. whereas typical molecular markers for apoptosis and ne ... | 2013 | 23388496 |
| the impact of low erythrocyte density in human blood on the fitness and energetic reserves of the african malaria vector anopheles gambiae. | anaemia is a common health problem in the developing world. this condition is characterized by a reduction in erythrocyte density, primarily from malnutrition and/or infectious diseases such as malaria. as red blood cells are the primary source of protein for haematophagous mosquitoes, any reduction could impede the ability of mosquito vectors to transmit malaria by influencing their fitness or that of the parasites they transmit. the aim of this study was to determine the impact of differences ... | 2013 | 23374331 |
| temperature-dependent pre-bloodmeal period and temperature-driven asynchrony between parasite development and mosquito biting rate reduce malaria transmission intensity. | a mosquito needs to bite at least twice for malaria transmission to occur: once to acquire parasites and, after these parasites complete their development in their mosquito host, once to transmit the parasites to the next vertebrate host. here we investigate the relationship between temperature, parasite development, and biting frequency in a mosquito-rodent malaria model system. we show that the pre-bloodmeal period (the time lag between mosquito emergence and first bloodmeal) increases at lowe ... | 2013 | 23383280 |
| expression of cytosolic peroxiredoxins in plasmodium berghei ookinetes is regulated by environmental factors in the mosquito bloodmeal. | the plasmodium ookinete develops over several hours in the bloodmeal of its mosquito vector where it is exposed to exogenous stresses, including cytotoxic reactive oxygen species (ros). how the parasite adapts to these challenging conditions is not well understood. we have systematically investigated the expression of three cytosolic antioxidant proteins, thioredoxin-1 (trx-1), peroxiredoxin-1 (tpx-1), and 1-cys peroxiredoxin (1-cys prx), in developing ookinetes of the rodent parasite plasmodium ... | 2013 | 23382676 |
| immunogenicity, protective efficacy and safety of a recombinant dna vaccine encoding truncated plasmodium yoelii sporozoite asparagine-rich protein 1 (pysap1). | although great efforts have been undertaken for the development of malaria vaccines, no completely effective malaria vaccines are available yet. despite being clinically silent, the pre-erythrocytic stage is considered an ideal target for the development of malaria vaccines. sporozoite asparagine-rich protein 1 (sap1) is a sporozoite-localized protein that regulates the expression of uis (upregulated in infectious sporozoites) genes, which are essential for the infectivity of sporozoites. in thi ... | 2013 | 23357857 |
| transgenic fluorescent plasmodium cynomolgi liver stages enable live imaging and purification of malaria hypnozoite-forms. | a major challenge for strategies to combat the human malaria parasite plasmodium vivax is the presence of hypnozoites in the liver. these dormant forms can cause renewed clinical disease after reactivation through unknown mechanisms. the closely related non-human primate malaria p. cynomolgi is a frequently used model for studying hypnozoite-induced relapses. here we report the generation of the first transgenic p. cynomolgi parasites that stably express fluorescent markers in liver stages by tr ... | 2013 | 23359816 |
| novel type ii fatty acid biosynthesis (fas ii) inhibitors as multistage antimalarial agents. | malaria is a potentially fatal disease caused by plasmodium parasites and poses a major medical risk in large parts of the world. the development of new, affordable antimalarial drugs is of vital importance as there are increasing reports of resistance to the currently available therapeutics. in addition, most of the current drugs used for chemoprophylaxis merely act on parasites already replicating in the blood. at this point, a patient might already be suffering from the symptoms associated wi ... | 2013 | 23341167 |
| total and putative surface proteomics of malaria parasite salivary gland sporozoites. | malaria infections of mammals are initiated by the transmission of plasmodium salivary gland sporozoites during an anopheles mosquito vector bite. sporozoites make their way through the skin and eventually to the liver, where they infect hepatocytes. blocking this initial stage of infection is a promising malaria vaccine strategy. therefore, comprehensively elucidating the protein composition of sporozoites will be invaluable in identifying novel targets for blocking infection. previous efforts ... | 2013 | 23325771 |
| human igf1 extends lifespan and enhances resistance to plasmodium falciparum infection in the malaria vector anopheles stephensi. | the highly conserved insulin/insulin-like growth factor (igf) signaling (iis) pathway regulates metabolism, development, lifespan and immunity across a wide range of organisms. previous studies have shown that human insulin ingested in the blood meal can activate mosquito iis, resulting in attenuated lifespan and increased malaria parasite infection. because human igf1 is present at higher concentrations in blood than insulin and is functionally linked with lifespan and immune processes, we pred ... | 0 | 23255191 |
| controlled human malaria infections by intradermal injection of cryopreserved plasmodium falciparum sporozoites. | controlled human malaria infection with sporozoites is a standardized and powerful tool for evaluation of malaria vaccine and drug efficacy but so far only applied by exposure to bites of plasmodium falciparum (pf)-infected mosquitoes. we assessed in an open label phase 1 trial, infection after intradermal injection of respectively 2,500, 10,000, or 25,000 aseptic, purified, vialed, cryopreserved pf sporozoites (pfspz) in three groups (n = 6/group) of healthy dutch volunteers. infection was safe ... | 2012 | 23149582 |
| quantification of sporozoite invasion, migration, and development by microscopy and flow cytometry. | there is an important role for in vitro assays to better understand the initial steps of malaria infection. in this section, we describe both microscopy-based and flow cytometry-based sporozoite invasion, migration and development assays with the rodent malaria parasites, plasmodium berghei and plasmodium yoelii, and the human malaria parasite, plasmodium falciparum. | 0 | 22990793 |
| 4(1h)-quinolones with liver stage activity against plasmodium berghei. | with the exception of primaquine, tafenoquine, and atovaquone, there are very few antimalarials that target liver stage parasites. in this study, a transgenic plasmodium berghei parasite (1052cl1; pbgfp-luc(con)) that expresses luciferase was used to assess the anti-liver stage parasite activity of ici 56,780, a 7-(2-phenoxyethoxy)-4(1h)-quinolone (peq), as well as two 3-phenyl-4(1h)-quinolones (p4q), p4q-146 and p4q-158, by using bioluminescent imaging (bli). results showed that all of the comp ... | 2012 | 23129047 |
| a class of tricyclic compounds blocking malaria parasite oocyst development and transmission. | malaria is a deadly infectious disease in many tropical and subtropical countries. previous efforts to eradicate malaria have failed, largely due to the emergence of drug-resistant parasites, insecticide-resistant mosquitoes and, in particular, the lack of drugs or vaccines to block parasite transmission. atp-binding cassette (abc) transporters are known to play a role in drug transport, metabolism, and resistance in many organisms, including malaria parasites. to investigate whether a plasmodiu ... | 2012 | 23129054 |
| genes involved in host-parasite interactions can be revealed by their correlated expression. | molecular interactions between a parasite and its host are key to the ability of the parasite to enter the host and persist. our understanding of the genes and proteins involved in these interactions is limited. to better understand these processes it would be advantageous to have a range of methods to predict pairs of genes involved in such interactions. correlated gene expression profiles can be used to identify molecular interactions within a species. here we have extended the concept to diff ... | 2012 | 23275547 |
| influence of hepatozoon parasites on host-seeking and host-choice behaviour of the mosquitoes culex territans and culex pipiens. | hepatozoon species are heteroxenous parasites that commonly infect the blood of vertebrates and various organs of arthropods. despite their ubiquity, little is known about how these parasites affect host phenotype, including whether or not these parasites induce changes in hosts to increase transmission success. the objectives of this research were to investigate influences of the frog blood parasite hepatozoon clamatae and the snake blood parasite hepatozoon sipedon on host-seeking and host-cho ... | 2012 | 24533317 |
| skin-draining lymph node priming is sufficient to induce sterile immunity against pre-erythrocytic malaria. | the plasmodium-infected hepatocyte has been considered necessary to prime the immune responses leading to sterile protection after vaccination with attenuated sporozoites. however, it has recently been demonstrated that priming also occurs in the skin. we wished to establish if sterile protection could be obtained in the absence of priming by infected hepatocytes. to this end, we developed a subcutaneous (s.c.) immunization protocol where few, possibly none, of the immunizing irradiated plasmodi ... | 2012 | 23255300 |
| a rapid and scalable density gradient purification method for plasmodium sporozoites. | malaria remains a major human health problem, with no licensed vaccine currently available. malaria infections initiate when infectious plasmodium sporozoites are transmitted by anopheline mosquitoes during their blood meal. investigations of the malaria sporozoite are, therefore, of clear medical importance. however, sporozoites can only be produced in and isolated from mosquitoes, and their isolation results in large amounts of accompanying mosquito debris and contaminating microbes. | 2012 | 23244590 |
| a tetracycline-repressible transactivator system to study essential genes in malaria parasites. | a major obstacle in analyzing gene function in apicomplexan parasites is the absence of a practical regulatable expression system. here, we identified functional transcriptional activation domains within apicomplexan ap2 (apiap2) family transcription factors. these apiap2 transactivation domains were validated in blood-, liver-, and mosquito-stage parasites and used to create a robust conditional expression system for stage-specific, tetracycline-dependent gene regulation in toxoplasma gondii, p ... | 0 | 23245327 |
| a systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies. | mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. these products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. the aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propose s ... | 2012 | 23216844 |
| mosquito transmission of the rodent malaria parasite plasmodium chabaudi. | serial blood passage of plasmodium increases virulence, whilst mosquito transmission inherently regulates parasite virulence within the mammalian host. it is, therefore, imperative that all aspects of experimental malaria research are studied in the context of the complete plasmodium life cycle. | 2012 | 23217144 |
| improvised microinjection technique for mosquito vectors. | bio-manipulation technique is of primary importance during the development of transgenic mosquitoes. the study describes the variable factors that influence the viability of medically important mosquito vectors during microinjection. | 0 | 23391792 |
| hiv nonnucleoside reverse transcriptase inhibitors and trimethoprim-sulfamethoxazole inhibit plasmodium liver stages. | although nonnucleoside reverse transcriptase inhibitors (nnrtis) are usually part of first-line treatment regimens for human immunodeficiency virus (hiv), their activity on plasmodium liver stages remains unexplored. additionally, trimethoprim-sulfamethoxazole (tmp-smx), used for opportunistic infection prophylaxis in hiv-exposed infants and hiv-infected patients, reduces clinical episodes of malaria; however, tmp-smx effect on plasmodium liver stages requires further study. | 0 | 23125449 |
| nf135.c10: a new plasmodium falciparum clone for controlled human malaria infections. | we established a new field clone of plasmodium falciparum for use in controlled human malaria infections and vaccine studies to complement the current small portfolio of p. falciparum strains, primarily based on nf54. the cambodian clone nf135.c10 consistently produced gametocytes and generated substantial numbers of sporozoites in anopheles mosquitoes and diverged from nf54 parasites by genetic markers. in a controlled human malaria infection trial, 3 of 5 volunteers challenged by mosquitoes in ... | 2012 | 23186785 |
| mitochondrial peroxidase tpx-2 is not essential in the blood and insect stages of plasmodium berghei. | malaria parasites actively proliferate in the body of their vertebrate and insect hosts, and are subjected to the toxic effects of reactive oxygen species. the antioxidant defenses of malaria parasites are considered to play essential roles in their survival and are thus considered promising targets for intervention. we sought to identify the cellular function of thioredoxin peroxidase-2 (tpx-2), which is expressed in the mitochondria, by disrupting the tpx-2 gene (pbtpx-2) of the rodent malaria ... | 2012 | 23146411 |
| identification of an ap2-family protein that is critical for malaria liver stage development. | liver-stage malaria parasites are a promising target for drugs and vaccines against malaria infection. however, little is currently known about gene regulation in this stage. in this study, we used the rodent malaria parasite plasmodium berghei and showed that an ap2-family transcription factor, designated ap2-l, plays a critical role in the liver-stage development of the parasite. ap2-l-depleted parasites proliferated normally in blood and in mosquitoes. however, the ability of these parasites ... | 2012 | 23144823 |
| evaluating the lethal and pre-lethal effects of a range of fungi against adult anopheles stephensi mosquitoes. | insecticide resistance is seriously undermining efforts to eliminate malaria. in response, research on alternatives to the use of chemical insecticides against adult mosquito vectors has been increasing. fungal entomopathogens formulated as biopesticides have received much attention and have shown considerable potential. this research has necessarily focused on relatively few fungal isolates in order to 'prove concept'. further, most attention has been paid to examining fungal virulence (lethali ... | 2012 | 23126549 |
| a nonintegrative lentiviral vector-based vaccine provides long-term sterile protection against malaria. | trials testing the rts,s candidate malaria vaccine and radiation-attenuated sporozoites (ras) have shown that protective immunity against malaria can be induced and that an effective vaccine is not out of reach. however, longer-term protection and higher protection rates are required to eradicate malaria from the endemic regions. it implies that there is still a need to explore new vaccine strategies. lentiviral vectors are very potent at inducing strong immunological memory. however their integ ... | 2012 | 23133649 |
| clinical trial in healthy malaria-naïve adults to evaluate the safety, tolerability, immunogenicity and efficacy of mustdo5, a five-gene, sporozoite/hepatic stage plasmodium falciparum dna vaccine combined with escalating dose human gm-csf dna. | when introduced in the 1990s, immunization with dna plasmids was considered potentially revolutionary for vaccine development, particularly for vaccines intended to induce protective cd8 t cell responses against multiple antigens. we conducted, in 1997-1998, the first clinical trial in healthy humans of a dna vaccine, a single plasmid encoding plasmodium falciparum circumsporozoite protein (pfcsp), as an initial step toward developing a multi-antigen malaria vaccine targeting the liver stages of ... | 2012 | 23151451 |
| gal4-based enhancer-trapping in the malaria mosquito anopheles stephensi. | transposon-based forward and reverse genetic technologies will contribute greatly to ongoing efforts to study mosquito functional genomics. a piggybac transposon-based enhancer-trap system was developed that functions efficiently in the human malaria vector, anopheles stephensi. the system consists of six transgenic lines of anopheles stephensi, each with a single piggybac-gal4 element in a unique genomic location; six lines with a single piggybac-uastdtomato element; and two lines, each with a ... | 2012 | 23173082 |
| protective antibody and cd8+ t-cell responses to the plasmodium falciparum circumsporozoite protein induced by a nanoparticle vaccine. | the worldwide burden of malaria remains a major public health problem due, in part, to the lack of an effective vaccine against the plasmodium falciparum parasite. an effective vaccine will most likely require the induction of antigen specific cd8(+) and cd4(+) t-cells as well as long-lasting antibody responses all working in concert to eliminate the infection. we report here the effective modification of a self-assembling protein nanoparticle (sapn) vaccine previously proven effective in contro ... | 2012 | 23144750 |
| natural transmission of plasmodium berghei exacerbates chronic tuberculosis in an experimental co-infection model. | human populations are rarely exposed to one pathogen alone. particularly in high incidence regions such as sub-saharan africa, concurrent infections with more than one pathogen represent a widely underappreciated public health problem. two of the world's most notorious killers, malaria and tuberculosis, are co-endemic in impoverished populations in the tropics. however, interactions between both infections in a co-infected individual have not been studied in detail. both pathogens have a major i ... | 2012 | 23110184 |
| storage and persistence of a candidate fungal biopesticide for use against adult malaria vectors. | new products aimed at augmenting or replacing chemical insecticides must have operational profiles that include both high efficacy in reducing vector numbers and/or blocking parasite transmission and be long lasting following application. research aimed at developing fungal spores as a biopesticide for vector control have shown considerable potential yet have not been directly assessed for their viability after long-term storage or following application in the field. | 2012 | 23098323 |
| chad63-mva-vectored blood-stage malaria vaccines targeting msp1 and ama1: assessment of efficacy against mosquito bite challenge in humans. | the induction of cellular immunity, in conjunction with antibodies, may be essential for vaccines to protect against blood-stage infection with the human malaria parasite plasmodium falciparum. we have shown that prime-boost delivery of p. falciparum blood-stage antigens by chimpanzee adenovirus 63 (chad63) followed by the attenuated orthopoxvirus mva is safe and immunogenic in healthy adults. here, we report on vaccine efficacy against controlled human malaria infection delivered by mosquito bi ... | 2012 | 23089736 |
| malaria elimination trend from a hypo-endemic unstable active focus in southern iran: predisposing climatic factors. | human malaria is the most important vector-borne infectious disease in iran. it remains focally endemic being restricted to almost 20 counties in three oriental provinces. as a result of control measures applied since 1988, these counties appear to be on the verge of eliminating malaria. malaria elimination strategy has thus become the new goal in iran. malaria due to plasmodium vivax, whose transmission is particularly hard to interrupt, accounts for nearly 90% of the cases. this study was thus ... | 0 | 23182141 |
| antibiotic and antimalarial quinones from fungus-growing ant-associated pseudonocardia sp. | three new members of the angucycline class of antibiotics, pseudonocardones a-c (1-3), along with the known antibiotics 6-deoxy-8-o-methylrabelomycin (4) and x-14881 e (5) have been isolated from the culture of a pseudonocardia strain associated with the fungus-growing ant apterostigma dentigerum. compounds 4 and 5 showed antibiotic activity against bacillus subtilis 3610 and liver-stage plasmodium berghei, while 1-3 were inactive or only weakly active in a variety of biological assays. compound ... | 2012 | 23025282 |
| conformational co-dependence between plasmodium berghei lccl proteins promotes complex formation and stability. | malaria parasites express a conserved family of lccl-lectin adhesive-like domain proteins (laps) that have essential functions in sporozoite transmission. in plasmodium falciparum all six family members are expressed in gametocytes and form a multi-protein complex. intriguingly, knockout of p. falciparum lccl proteins adversely affects expression of other family members at protein, but not at mrna level, a phenomenon termed co-dependent expression. here, we investigate this in plasmodium berghei ... | 2012 | 22877575 |
| draft genome sequences of enterobacter sp. isolate ag1 from the midgut of the malaria mosquito anopheles gambiae. | an isolate of enterobacter sp. was obtained from the microbial community within the gut of the anopheles gambiae mosquito, a major malaria vector in africa. this genome was sequenced and annotated. the genome sequences will facilitate subsequent efforts to characterize the mosquito gut microbiome. | 0 | 22965099 |
| tricks in plasmodium's molecular repertoire--escaping 3'utr excision-based conditional silencing of the chloroquine resistance transporter gene. | in the human malaria parasite plasmodium falciparum, the major determinant of chloroquine resistance, p. falciparum chloroquine resistance transporter (pfcrt), likely plays an essential role in asexual blood stages, thus precluding conventional gene targeting approaches. we attempted to conditionally silence the expression of its ortholog in plasmodium berghei (pbcrt) through flp recombinase-mediated excision of the 3'untranslated region (utr) during mosquito passage. however, parasites maintain ... | 2012 | 23023047 |
| virulence, drug sensitivity and transmission success in the rodent malaria, plasmodium chabaudi. | here, we test the hypothesis that virulent malaria parasites are less susceptible to drug treatment than less virulent parasites. if true, drug treatment might promote the evolution of more virulent parasites (defined here as those doing more harm to hosts). drug-resistance mechanisms that protect parasites through interactions with drug molecules at the sub-cellular level are well known. however, parasite phenotypes associated with virulence might also help parasites survive in the presence of ... | 2012 | 23015626 |
| a unique protein phosphatase with kelch-like domains (ppkl) in plasmodium modulates ookinete differentiation, motility and invasion. | protein phosphorylation and dephosphorylation (catalysed by kinases and phosphatases, respectively) are post-translational modifications that play key roles in many eukaryotic signalling pathways, and are often deregulated in a number of pathological conditions in humans. in the malaria parasite plasmodium, functional insights into its kinome have only recently been achieved, with over half being essential for blood stage development and another 14 kinases being essential for sexual development ... | 2012 | 23028336 |
| screening of selected ethnomedicinal plants from south africa for larvicidal activity against the mosquito anopheles arabiensis. | this study was initiated to establish whether any south african ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito larvicidal properties. | 2012 | 22963538 |
| complete plasmodium falciparum liver-stage development in liver-chimeric mice. | plasmodium falciparum, which causes the most lethal form of human malaria, replicates in the host liver during the initial stage of infection. however, in vivo malaria liver-stage (ls) studies in humans are virtually impossible, and in vitro models of ls development do not reconstitute relevant parasite growth conditions. to overcome these obstacles, we have adopted a robust mouse model for the study of p. falciparum ls in vivo: the immunocompromised and fumarylacetoacetate hydrolase-deficient m ... | 2012 | 22996664 |
| comparative transcriptome analyses of deltamethrin-resistant and -susceptible anopheles gambiae mosquitoes from kenya by rna-seq. | malaria causes more than 300 million clinical cases and 665,000 deaths each year, and the majority of the mortality and morbidity occurs in sub-saharan africa. due to the lack of effective vaccines and wide-spread resistance to antimalarial drugs, mosquito control is the primary method of malaria prevention and control. currently, malaria vector control relies on the use of insecticides, primarily pyrethroids. the extensive use of insecticides has imposed strong selection pressures for resistanc ... | 2012 | 22970263 |
| oviposition-stimulant and ovicidal activities of moringa oleifera lectin on aedes aegypti. | natural insecticides against the vector mosquito aedes aegypti have been the object of research due to their high level of eco-safety. the water-soluble moringa oleifera lectin (wsmol) is a larvicidal agent against a. aegypti. this work reports the effects of wsmol on oviposition and egg hatching of a. aegypti. | 2012 | 22970317 |
| a unique kelch domain phosphatase in plasmodium regulates ookinete morphology, motility and invasion. | signalling through post-translational modification (ptm) of proteins is a process central to cell homeostasis, development and responses to external stimuli. the best characterised ptm is protein phosphorylation which is reversibly catalysed at specific residues through the action of protein kinases (addition) and phosphatases (removal). here, we report characterisation of an orphan protein phosphatase that possesses a domain architecture previously only described in plantae. through gene disrup ... | 2012 | 22957089 |
| variation in apoptosis mechanisms employed by malaria parasites: the roles of inducers, dose dependence and parasite stages. | plasmodium berghei ookinetes exhibit an apoptotic phenotype when developing within the mosquito midgut lumen or when cultured in vitro. markers of apoptosis increase when they are exposed to nitric oxide or reactive oxygen species but high concentrations of hydrogen peroxide cause death without observable signs of apoptosis. chloroquine and other drugs have been used to induce apoptosis in erythrocytic stages of plasmodium falciparum and to formulate a putative pathway involving cysteine proteas ... | 2012 | 22929459 |
| review of pyronaridine anti-malarial properties and product characteristics. | pyronaridine was synthesized in 1970 at the institute of chinese parasitic disease and has been used in china for over 30 years for the treatment of malaria. pyronaridine has high potency against plasmodium falciparum, including chloroquine-resistant strains. studies in various animal models have shown pyronaridine to be effective against strains resistant to other anti-malarials, including chloroquine. resistance to pyronaridine appears to emerge slowly and is further retarded when pyronaridine ... | 2012 | 22877082 |
| one injection of dsred followed by bites from transgenic mosquitoes producing dsred in the saliva elicits a high titer of antibody in mice. | it has been proposed that transgenic mosquitoes can be used as a "flying syringe" for infectious disease control. we succeeded in generating a transgenic (tg) mosquito, anopheles stephensi, excreting and discharging dsred in saliva. dsred was deposited on the membrane where the tg mosquito probed with its proboscis. repeated feeding by the tg mosquitoes induced anti-dered as well as anti-sg antibodies in mice. this indicates that the tg mosquitoes can immunize the animal. moreover, in this repor ... | 2012 | 23097619 |
| structural basis for chirality and directional motility of plasmodium sporozoites. | plasmodium sporozoites can move at high speed for several tens of minutes, which is essential for the initial stage of a malaria infection. the crescent-shaped sporozoites move on 2d substrates preferably in the same direction on circular paths giving raise to helical paths in 3d matrices. here we determined the structural basis that underlies this type of movement. immature, non-motile sporozoites were found to lack the subpellicular network required for obtaining the crescent parasite shape. i ... | 2012 | 22776715 |
| shedding of trap by a rhomboid protease from the malaria sporozoite surface is essential for gliding motility and sporozoite infectivity. | plasmodium sporozoites, the infective stage of the malaria parasite, move by gliding motility, a unique form of locomotion required for tissue migration and host cell invasion. trap, a transmembrane protein with extracellular adhesive domains and a cytoplasmic tail linked to the actomyosin motor, is central to this process. forward movement is achieved when trap, bound to matrix or host cell receptors, is translocated posteriorly. it has been hypothesized that these adhesive interactions must ul ... | 2012 | 22911675 |
| a plasmodium calcium-dependent protein kinase controls zygote development and transmission by translationally activating repressed mrnas. | calcium-dependent protein kinases (cdpks) play key regulatory roles in the life cycle of the malaria parasite, but in many cases their precise molecular functions are unknown. using the rodent malaria parasite plasmodium berghei, we show that cdpk1, which is known to be essential in the asexual blood stage of the parasite, is expressed in all life stages and is indispensable during the sexual mosquito life-cycle stages. knockdown of cdpk1 in sexual stages resulted in developmentally arrested par ... | 0 | 22817984 |
| enhanced survival of plasmodium-infected mosquitoes during starvation. | plasmodium spp. are pathogenic to their vertebrate hosts and also apparently, impose a fitness cost on their insect vectors. we show here, however, that plasmodium-infected mosquitoes survive starvation significantly better than uninfected mosquitoes. this survival advantage during starvation is associated with higher energy resource storage that infected mosquitoes accumulate during period of plasmodium oocyst development. microarray analysis revealed that the metabolism of sated mosquitoes is ... | 2012 | 22808193 |
| development of an allele-specific, loop-mediated, isothermal amplification method (as-lamp) to detect the l1014f kdr-w mutation in anopheles gambiae s. l. | malaria control relies heavily on treated bed nets and indoor residual spraying with pyrethroid insecticides. unfortunately, the resistance to pyrethroid insecticides, mainly due to the kdr mutation, is spreading in the main malaria vector anopheles gambiae s.l., decreasing the insecticides' efficacy. to manage the insecticide resistance rapidly and flexibly, simple and effective tools for the early detection of resistant mosquitoes are needed. this study aimed to develop an allele-specific, loo ... | 2012 | 22770418 |
| distinct biological effects of golgicide a derivatives on larval and adult mosquitoes. | a collection of golgicide a (gca) analogs has been synthesized and evaluated in larval and adult mosquito assays. commercially available gca is a mixture of four compounds. one enantiomer (gca-2) of the major diastereomer in this mixture was shown to be responsible for the unique activity of gca. structure-activity studies (sar) of the gca architecture suggested that the pyridine ring was most easily manipulated without loss or gain in new activity. eighteen gca analogs were synthesized of which ... | 2012 | 22818079 |
| 3'-race amplification of aminopeptidase n gene from anopheles stephensi applicable in transmission blocking vaccines. | because of the lack of an effective and economical control strategy against malaria (the most devastating infectious disease in developing countries) transmission-blocking vaccines (tbvs) concept has been raised in recent years, promising a more efficient way to malaria control. tbvs aim at interfering and/or blocking pathogen development within the vector, halting transmission to non-infected vertebrate host. aminopeptidase n (apn) is one of the most potent proteins in parasite development in a ... | 0 | 23407363 |
| a review: ethnobotanical survey of genus leucas. | plants of genus leucas (lamiaceae) are widely distributed throughout asia, africa, and india. the plant is used in traditional medicine to cure many diseases such as cough, cold, diarrhea, and inflammatory skin disorder. a variety of phytoconstituents have been isolated from the leucas species, which include lignans, flavonoids, coumarins, steroids, terpenes, fatty acids, and aliphatic long-chain compounds. anti-inflammatory, analgesic, anti-diarrheal, antimicrobial, antioxidant, and insecticida ... | 0 | 23055635 |
| the spiroindolone drug candidate nitd609 potently inhibits gametocytogenesis and blocks plasmodium falciparum transmission to anopheles mosquito vector. | the global malaria agenda has undergone a reorientation from control of clinical cases to entirely eradicating malaria. for that purpose, a key objective is blocking transmission of malaria parasites from humans to mosquito vectors. the new antimalarial drug candidate nitd609 was evaluated for its transmission-reducing potential and compared to a few established antimalarials (lumefantrine, artemether, primaquine), using a suite of in vitro assays. by the use of a microscopic readout, nitd609 wa ... | 2012 | 22508309 |
| antimalarial activity of the anticancer histone deacetylase inhibitor sb939. | histone deacetylase (hdac) enzymes posttranslationally modify lysines on histone and nonhistone proteins and play crucial roles in epigenetic regulation and other important cellular processes. hdac inhibitors (e.g., suberoylanilide hydroxamic acid [saha; also known as vorinostat]) are used clinically to treat some cancers and are under investigation for use against many other diseases. development of new hdac inhibitors for noncancer indications has the potential to be accelerated by piggybackin ... | 2012 | 22508312 |
| flp recombinase-mediated site-specific recombination in silkworm, bombyx mori. | a comprehensive understanding of gene function and the production of site-specific genetically modified mutants are two major goals of genetic engineering in the post-genomic era. although site-specific recombination systems have been powerful tools for genome manipulation of many organisms, they have not yet been established for use in the manipulation of the silkworm bombyx mori genome. in this study, we achieved site-specific excision of a target gene at predefined chromosomal sites in the si ... | 2012 | 22768245 |
| hybridization in situ of salivary glands, ovaries, and embryos of vector mosquitoes. | mosquitoes are vectors for a diverse set of pathogens including arboviruses, protozoan parasites and nematodes. investigation of transcripts and gene regulators that are expressed in tissues in which the mosquito host and pathogen interact, and in organs involved in reproduction are of great interest for strategies to reduce mosquito-borne disease transmission and disrupt egg development. a number of tools have been employed to study and validate the temporal and tissue-specific regulation of ge ... | 2012 | 22781778 |
| transgenic anopheles stephensi coexpressing single-chain antibodies resist plasmodium falciparum development. | anopheles stephensi mosquitoes expressing m1c3, m4b7, or m2a10 single-chain antibodies (scfvs) have significantly lower levels of infection compared to controls when challenged with plasmodium falciparum, a human malaria pathogen. these scfvs are derived from antibodies specific to a parasite chitinase, the 25 kda protein and the circumsporozoite protein, respectively. transgenes comprising m2a10 in combination with either m1c3 or m4b7 were inserted into previously-characterized mosquito chromos ... | 2012 | 22689959 |
| comparison of clinical and parasitological data from controlled human malaria infection trials. | exposing healthy human volunteers to plasmodium falciparum-infected mosquitoes is an accepted tool to evaluate preliminary efficacy of malaria vaccines. to accommodate the demand of the malaria vaccine pipeline, controlled infections are carried out in an increasing number of centers worldwide. we assessed their safety and reproducibility. | 2012 | 22701640 |
| pcr detection of malaria parasites in desiccated anopheles mosquitoes is uninhibited by storage time and temperature. | reliable methods to preserve mosquito vectors for malaria studies are necessary for detecting plasmodium parasites. in field settings, however, maintaining a cold chain of storage from the time of collection until laboratory processing, or accessing other reliable means of sample preservation is often logistically impractical or cost prohibitive. as the plasmodium infection rate of anopheles mosquitoes is a central component of the entomological inoculation rate and other indicators of transmiss ... | 2012 | 22682161 |
| enhanced transmission of drug-resistant parasites to mosquitoes following drug treatment in rodent malaria. | the evolution of drug resistant plasmodium parasites is a major challenge to effective malaria control. in theory, competitive interactions between sensitive parasites and resistant parasites within infections are a major determinant of the rate at which parasite evolution undermines drug efficacy. competitive suppression of resistant parasites in untreated hosts slows the spread of resistance; competitive release following treatment enhances it. here we report that for the murine model plasmodi ... | 2012 | 22701563 |
| the role of male harassment on female fitness for the dengue vector mosquito aedes aegypti. | sexual harassment studies in insects suggest that females can incur several kinds of costs from male harassment and mating. here, we examined direct and indirect costs of male harassment on components of female fitness in the predominantly monandrous mosquito aedes aegypti. to disentangle the costs of harassment versus the costs of mating, we held females at a low or high density with males whose claspers were modified to prevent insemination, and compared these to females held with normal males ... | 0 | 25544799 |
| extrahepatic exoerythrocytic forms of rodent malaria parasites at the site of inoculation: clearance after immunization, susceptibility to primaquine, and contribution to blood-stage infection. | plasmodium sporozoites are inoculated into the skin of the mammalian host as infected mosquitoes probe for blood. a proportion of the inoculum enters the bloodstream and goes to the liver, where the sporozoites invade hepatocytes and develop into the next life cycle stage, the exoerythrocytic, or liver, stage. here, we show that a small fraction of the inoculum remains in the skin and begins to develop into exoerythrocytic forms that can persist for days. skin exoerythrocytic forms were observed ... | 2012 | 22431651 |
| ingested human insulin inhibits the mosquito nf-κb-dependent immune response to plasmodium falciparum. | we showed previously that ingested human insulin activates the insulin/igf-1 signaling pathway in anopheles stephensi and increases the susceptibility of these mosquitoes to plasmodium falciparum. in other organisms, insulin can alter immune responsiveness through regulation of nf-κb transcription factors, critical elements for innate immunity that are also central to mosquito immunity. we show here that insulin signaling decreased expression of nf-κb-regulated immune genes in mosquito cells sti ... | 2012 | 22473605 |
| pfe0565w, a plasmodium falciparum protein expressed in salivary gland sporozoites. | because malaria is still a significant problem worldwide, additional control methods need to be developed. the plasmodium sporozoite is a good target for control measures because it displays dual infectivity for both mosquito and vertebrate host tissues. the plasmodium falciparum gene, pfe0565w, was chosen as a candidate for study based on data from plasmodb, the plasmodium database, indicating that it is expressed both at the transcriptional and protein levels in sporozoites, likely encodes a p ... | 0 | 22665598 |