| geohelminths: public health significance. | the worldwide prevalence of geohelminths and their unique place in evolutionary biology have attracted research focus. these major soil-transmitted intestinal nematodes that cause human diseases are the nematode roundworm (ascaris lumbricoides), the whipworm (trichuris trichiura) and the two hookworms (ancylostoma duodenale and necator americanus), often collectively referred as geohelminths. studies of geohelminthiasis in poorly nourished children in developing regions report that geohelminths ... | 2014 | 24423707 |
| controlling soil-transmitted helminths: time to think inside the box? | soil-transmitted helminths (sth) refer to several parasitic nematode species that infect over 1 billion people worldwide. infections with ascaris lumbricoides , trichuris trichiura , and the hookworms necator americanus and ancylostoma duodenale cause significant morbidity in more than 450 million people, primarily children and pregnant women, resulting in over 39 million disability-adjusted life years lost. considerable effort and resources have been, and continue to be, spent on top-down, medi ... | 2014 | 24393037 |
| impact of helminth diagnostic test performance on estimation of risk factors and outcomes in hiv-positive adults. | traditional methods using microscopy for the detection of helminth infections have limited sensitivity. polymerase chain reaction (pcr) assays enhance detection of helminths, particularly low burden infections. however, differences in test performance may modify the ability to detect associations between helminth infection, risk factors, and sequelae. we compared these associations using microscopy and pcr. | 2013 | 24324729 |
| update on the mapping of prevalence and intensity of infection for soil-transmitted helminth infections in latin america and the caribbean: a call for action. | it is estimated that in latin america and the caribbean (lac) at least 13.9 million preschool age and 35.4 million school age children are at risk of infections by soil-transmitted helminths (sth): ascaris lumbricoides, trichuris trichiura and hookworms (necator americanus and ancylostoma duodenale). although infections caused by this group of parasites are associated with chronic deleterious effects on nutrition and growth, iron and vitamin a status and cognitive development in children, few co ... | 2013 | 24069476 |
| discrimination of gastrointestinal nematode eggs from crude fecal egg preparations by inhibitor-resistant conventional and real-time pcr. | diagnosis of gastrointestinal nematodes relies predominantly on coproscopic methods such as flotation, kato-katz, mcmaster or flotac. although flotac allows accurate quantification, many nematode eggs can only be differentiated to genus or family level. several molecular diagnostic tools discriminating closely related species suffer from high costs for dna isolation from feces and limited sensitivity since most kits use only small amounts of feces (<1 g). a direct pcr from crude egg preparations ... | 2013 | 23620739 |
| influence of physico-chemistry and mineralogy on the occurrence of geohelminths in geophagic soils from selected communities in the eastern cape, south africa, and their possible implication on human health. | geophagic soils from selected communities in eastern cape, south africa were characterised to determine their properties and geohelminth content. the soils were coarse-textured with cation exchange capacity values ranging from 6.35 to 18.94 cmol (+)/kg. quartz was the dominant mineral in the samples with sio2, al2o3, and fe2o3(t) having the highest concentrations among major element oxides. the soil properties, mineralogical composition, and low amounts of particle binding substances may favour ... | 2014 | 23574040 |
| soil-transmitted helminth infection in south america: a systematic review and geostatistical meta-analysis. | the four common soil-transmitted helminth species-ascaris lumbricoides, trichuris trichiura, and the two hookworm species ancylostoma duodenale and necator americanus-are endemic in south america, but their distribution, infection prevalence, and regional burden are poorly understood. we aimed to estimate the risk and number of people infected with a lumbricoides, t trichiura, and hookworm across south america. | 2013 | 23562238 |
| a novel, multi-parallel, real-time polymerase chain reaction approach for eight gastrointestinal parasites provides improved diagnostic capabilities to resource-limited at-risk populations. | diagnosis of gastrointestinal parasites has traditionally relied on stool microscopy, which has low diagnostic sensitivity and specificity. we have developed a novel, rapid, high-throughput quantitative multi-parallel real-time polymerase chain reaction (qpcr) platform. species-specific primers/probes were used for eight common gastrointestinal parasite pathogens: ascaris lumbricoides, necator americanus, ancylostoma duodenale, giardia lamblia, cryptosporidium spp., entamoeba histolytica, trichu ... | 2013 | 23509117 |
| relationship between carotid intima media thickness and helminth infections on flores island, indonesia. | to examine the association between helminth infections and atherosclerosis. | 2013 | 23365679 |
| evaluation of real-time pcr for strongyloides stercoralis and hookworm as diagnostic tool in asymptomatic schoolchildren in cambodia. | diagnosis of soil-transmitted helminths such as strongyloides stercoralis and hookworms (ancylostoma duodenale and necator americanus) is challenging due to irregular larval and egg output in infected individuals and insensitive conventional diagnostic procedures. sensitive novel real-time pcr assays have been developed. our study aimed to evaluate the real-time pcr assays as a diagnostic tool for detection of strongyloides spp. and hookworms in a random stool sample of 218 asymptomatic schoolch ... | 2013 | 23298731 |
| hookworm virulence factors: making the most of the host. | hookworm disease from necator americanus and ancylostoma duodenale affects approximately 700 million people, with n. americanus being the predominant species. unlike other pathogens (e.g., bacterial infections), where "virulence" is described in regards to acute pathogenesis and case-fatality, hookworms are well-evolved, multicellular parasites that establish long-term infections in their human hosts with a subtle and chronic, but insidious, pathogenesis, usually in the form of iron deficiency a ... | 2012 | 23006854 |
| parasitic diseases of the pleura. | parasitic infections are prevalent in certain parts of the world and may cause pleural involvement, which often goes unrecognized. common parasites involving the pleura include entamoeba histolytica, echinococcus granulosus and paragonimus westermani. amebiasis can cause empyema with "anchovy sauce" pus, reactive pleural effusions and bronchopleural fistula with hydropneumothorax. echinococcosis may result in pleural thickening, pneumothorax, secondary pleural hydatidosis and pleural effusions. ... | 2013 | 22990049 |
| determining soil-transmitted helminth infection status and physical fitness of school-aged children. | soil-transmitted helminth (sth) infections are common. indeed, more than 1 billion people are affected, mainly in the developing world where poverty prevails and hygiene behavior, water supply, and sanitation are often deficient. ascaris lumbricoides, trichuris trichiura, and the two hookworm species, ancylostoma duodenale and necator americanus, are the most prevalent sths. the estimated global burden due to hookworm disease, ascariasis, and trichuriasis is 22.1, 10.5, and 6.4 million disabilit ... | 2012 | 22951972 |
| malaria and helminthic co-infection among hiv-positive pregnant women: prevalence and effects of antiretroviral therapy. | the impact of malaria on anemia and the interplay with helminths underline the importance of addressing the interactions between hiv/aids, malaria and intestinal helminth infections in pregnancy. the aim of this study was to determine the prevalence of malaria-helminth dual infections among hiv positive pregnant mothers after 12 months of art. a cross sectional study was conducted on intestinal helminths and malaria dual infections among hiv-positive pregnant women attending antenatal health cen ... | 2012 | 22940013 |
| real-time pcr demonstrates ancylostoma duodenale is a key factor in the etiology of severe anemia and iron deficiency in malawian pre-school children. | hookworm infections are an important cause of (severe) anemia and iron deficiency in children in the tropics. type of hookworm species (ancylostoma duodenale or necator americanus) and infection load are considered associated with disease burden, although these parameters are rarely assessed due to limitations of currently used diagnostic methods. using multiplex real-time pcr, we evaluated hookworm species-specific prevalence, infection load and their contribution towards severe anemia and iron ... | 2012 | 22514750 |
| overt gastrointestinal bleeding because of hookworm infection. | hookworm infection is a relatively common cause of anemia in endemic areas. the most common hookworm species are ancylostoma duodenale and necator americanus. in this report we present a case of overt gastrointestinal bleeding because of hookworm infection. capsule endoscopy revealed many hookworms in the lumen of proximal jejunum where active bleeding was seen. the patient was successfully treated with albendazole. | 2012 | 22449530 |
| is anthelmintic resistance a concern for the control of human soil-transmitted helminths? | the major human soil-transmitted helminths (sth), ascaris lumbricoides, hookworms (necator americanus and ancylostoma duodenale) and trichuris trichiura have a marked impact on human health in many parts of the world. current efforts to control these parasites rely predominantly on periodic mass administration of anthelmintic drugs to school age children and other at-risk groups. after many years of use of these same drugs for controlling roundworms in livestock, high levels of resistance have d ... | 2011 | 24533260 |
| draft genome of neurotropic nematode parasite angiostrongylus cantonensis, causative agent of human eosinophilic meningitis. | angiostrongylus cantonensis is a bursate nematode parasite that causes eosinophilic meningitis (or meningoencephalitis) in humans in many parts of the world. the genomic data from a. cantonensis will form a useful resource for comparative genomic and chemogenomic studies to aid the development of diagnostics and therapeutics. we have sequenced, assembled and annotated the genome of a. cantonensis. the genome size is estimated to be ∼260 mb, with 17,280 genomic scaffolds, 91x coverage, 81.45% for ... | 2015 | 25910624 |
| [investigation on spread and hazards of human parasites in qushui village, suixi county, zhanjiang city]. | to understand the transmission of human parasites in qushui village, yangqing town, suixi county, zhanjing city, guangdong province. | 2012 | 23236799 |
| improved diagnosis of trichuris trichiura by using a bead-beating procedure on ethanol preserved stool samples prior to dna isolation and the performance of multiplex real-time pcr for intestinal parasites. | for the majority of intestinal parasites, real-time pcr-based diagnosis outperforms microscopy. however, the data for trichuris trichiura have been less convincing and most comparative studies have been performed in populations with low prevalence. this study aims to improve detection of t. trichuria dna in human stool by evaluating four sample preparation methods. faecal samples (n = 60) were collected at flores island, indonesia and examined by microscopy. aliquots were taken and a bead-beatin ... | 2017 | 28290266 |
| water, sanitation and hygiene related risk factors for soil-transmitted helminth and giardia duodenalis infections in rural communities in timor-leste. | there is little evidence on prevalence or risk factors for soil transmitted helminth infections in timor-leste. this study describes the epidemiology, water, sanitation and hygiene, and socioeconomic risk factors of sth and intestinal protozoa amongst communities in manufahi district, timor-leste. as part of a cluster randomised controlled trial, a baseline cross-sectional survey was conducted across 18 villages, with data from six additional villages. stool samples were assessed for soil transm ... | 2016 | 27616734 |
| prevalence of soil-transmitted helminths and molecular clarification of hookworm species in ethnic ede primary schoolchildren in dak lak province, southern vietnam. | to know the infection status of helminths in primary schoolchildren of southern parts of vietnam, we performed an epidemiological study in krong pac district, dak lak province, vietnam. a total of 1,206 stool specimens were collected from ethnic ede schoolchildren in 4 primary schools in 2015 and examined by the kato-katz technique. in addition, stool cultures were done by the harada-mori method to obtain hookworm larvae and then to clarify the species of hookworms infected. the results showed t ... | 2016 | 27658599 |
| the right tool for the job: detection of soil-transmitted helminths in areas co-endemic for other helminths. | due to the recent increased use of the mcmaster (mm) fecal egg counting method for assessing benzimidazole drug efficacy for treating soil-transmitted helminth (sth) infections, the aim of the current study was to determine the operational value of including the mm method alongside the kato-katz (kk) fecal thick smear to increase the diagnostic sensitivity when sths are co-endemic with trematode helminths (e.g., schistosoma mansoni). | 2015 | 26241329 |
| multiplex real-time pcr monitoring of intestinal helminths in humans reveals widespread polyparasitism in northern samar, the philippines. | the global socioeconomic importance of helminth parasitic disease is underpinned by the considerable clinical impact on millions of people. while helminth polyparasitism is considered common in the philippines, little has been done to survey its extent in endemic communities. high morphological similarity of eggs between related species complicates conventional microscopic diagnostic methods which are known to lack sensitivity, particularly in low intensity infections. multiplex quantitative pcr ... | 2015 | 25858090 |
| pcr for enteric pathogens in high-prevalence settings. what does a positive signal tell us? | molecular methods, in particular pcr, are increasingly used for the diagnosis of enteric pathogens in stool samples. in high-endemicity settings, however, asymptomatic carriage or residual dna from previous infections will hamper the interpretation of positive test results. we assessed the quantitative dimension of this problem in schoolchildren in the rural highlands of madagascar. | 2015 | 25761823 |
| cellular cytokine and chemokine responses to parasite antigens and fungus and mite allergens in children co-infected with helminthes and protozoa parasites. | in sub-saharan africa poly-parasite infections are frequently observed in children, and with poly-parasitism modulating immune mechanisms, mediated by cytokines and chemokines, are required to prevent overwhelming inflammation and host tissue damage. we analyzed in children co-infected with helminthes and protozoan parasites their cellular production of regulatory and pro-inflammatory cytokines and chemokines in response to parasite antigens and allergens. | 2015 | 25698903 |
| triplex polymerase chain reaction assay for detection of major soil-transmitted helminths, ascaris lumbricoides, trichuris trichiura, necator americanus, in fecal samples. | ascaris lumbricoides, trichuris trichiura, and necator americanus are medically important soil-transmitted helminths (sths) occurring frequently worldwide including thailand. fecal examination using a microscope has been recommended as the gold standard for diagnosis of sth infections, but suffers from low sensitivity. recently, highly sensitive and specific assays, such as multiplex quantitative pcr, has been established, but the high cost and need for special instruments are still barriers lim ... | 2014 | 24968666 |
| do shoes reduce hookworm infection in school-aged children on pemba island, zanzibar? a pragmatic trial. | a non-blinded, cluster randomised controlled trial to test whether footwear reduces prevalence and intensity of hookworm infection in school-aged children on pemba island, zanzibar. | 2014 | 24603321 |
| serum ccl11 (eotaxin-1) and ccl17 (tarc) are serological indicators of multiple helminth infections and are driven by schistosoma mansoni infection in humans. | to evaluate systemic serum cytokine and chemokine markers for inflammation and th1/th2 responses in relation to multiple helminth infections, parasite burden and/or nutritional status of individuals. | 2013 | 23496801 |
| a comparative study of intestinal helminths in pre-school-age urban and rural children in morobe province, papua new guinea. | children aged between 1 month and 10 years from one rural coastal locality, two rural upland localities and two urban localities in morobe province, papua new guinea were examined between september 1980 and september 1982. hookworm (predominantly necator americanus), ascaris lumbricoides and trichuris trichiura increased in prevalence with age. the prevalence of strongyloides fuelleborni subspecies kellyi, where present, was either highest in the < 1 year age group or similar in all age groups. ... | 2014 | 25507576 |
| a comparative study of intestinal helminths in pre-school-age urban and rural children in morobe province, papua new guinea. | children aged between 1 month and 10 years from one rural coastal locality, two rural upland localities and two urban localities in morobe province, papua new guinea were examined between september 1980 and september 1982. hookworm (predominantly necator americanus), ascaris lumbricoides and trichuris trichiura increased in prevalence with age. the prevalence of strongyloides fuelleborni subspecies kellyi, where present, was either highest in the < 1 year age group or similar in all age groups. ... | 2014 | 25423854 |
| [intestinal parasites in children in biankouma, ivory coast (mountaineous western region): efficacy and safety of praziquantel and albendazole]. | schistosomiasis and soil-transmitted helminthiasis are a global public health problem, especially among schoolchildren. the purpose of this study was to determine the overall and specific prevalences of intestinal helminth infection and to assess the clinical efficacy, tolerance, and safety of praziquantel and albendazole for treating it. a descriptive cross-sectional study based on random sampling with one degree of freedom was conducted from november 2006 to march 2007 in the primary schools o ... | 2016 | 23107664 |
| timps of parasitic helminths - a large-scale analysis of high-throughput sequence datasets. | tissue inhibitors of metalloproteases (timps) are a multifunctional family of proteins that orchestrate extracellular matrix turnover, tissue remodelling and other cellular processes. in parasitic helminths, such as hookworms, timps have been proposed to play key roles in the host-parasite interplay, including invasion of and establishment in the vertebrate animal hosts. currently, knowledge of helminth timps is limited to a small number of studies on canine hookworms, whereas no information is ... | 2013 | 23721526 |
| genome mining offers a new starting point for parasitology research. | parasites including helminthes, protozoa, and medical arthropod vectors are a major cause of global infectious diseases, affecting one-sixth of the world's population, which are responsible for enormous levels of morbidity and mortality important and remain impediments to economic development especially in tropical countries. prevalent drug resistance, lack of highly effective and practical vaccines, as well as specific and sensitive diagnostic markers are proving to be challenging problems in p ... | 2015 | 25563615 |
| pan-phylum comparison of nematode metabolic potential. | nematodes are among the most important causative pathogens of neglected tropical diseases. the increased availability of genomic and transcriptomic data for many understudied nematode species provides a great opportunity to investigate different aspects of their biology. increasingly, metabolic potential of pathogens is recognized as a critical determinant governing their development, growth and pathogenicity. comparing metabolic potential among species with distinct trophic ecologies can provid ... | 2015 | 26000881 |
| pathogenic eukaryotes in gut microbiota of western lowland gorillas as revealed by molecular survey. | although gorillas regarded as the largest extant species of primates and have a close phylogenetic relationship with humans, eukaryotic communities have not been previously studied in these populations. herein, 35 eukaryotic primer sets targeting the 18s rrna gene, internal transcribed spacer gene and other specific genes were used firstly to explore the eukaryotes in a fecal sample from a wild western lowland gorilla (gorilla gorilla gorilla). then specific real-time pcrs were achieved in addit ... | 2014 | 25231746 |
| new vaccines for neglected parasitic diseases and dengue. | neglected tropical diseases (ntds) are a significant source of morbidity and socioeconomic burden among the world's poor. virtually all of the 2.4 billion people who live on less than $2 per d, more than a third of the world's population, are at risk for these debilitating ntds. although chemotherapeutic measures exist for many of these pathogens, they are not sustainable countermeasures on their own because of rates of reinfection, risk of drug resistance, and inconsistent maintenance of drug t ... | 2013 | 23578479 |
| [intestinal parasitosis among non-permanent resident students in tunisia: a review of 23 years of monitoring in the department of parasitology-mycology at the rabta hospital of tunisia]. | in order to fight digestive parasitism in tunisia, a national program of surveillance of non-permanent resident students in tunisia has been found to detect these parasitosis in this target population. | 2015 | 26757499 |
| application of a multiplex quantitative pcr to assess prevalence and intensity of intestinal parasite infections in a controlled clinical trial. | accurate quantitative assessment of infection with soil transmitted helminths and protozoa is key to the interpretation of epidemiologic studies of these parasites, as well as for monitoring large scale treatment efficacy and effectiveness studies. as morbidity and transmission of helminth infections are directly related to both the prevalence and intensity of infection, there is particular need for improved techniques for assessment of infection intensity for both purposes. the current study ai ... | 2016 | 26820626 |
| enteric pathogens of food sellers in rural gambia with incidental finding of myxobolus species (protozoa: myxozoa). | ongoing surveillance of enteric pathogens of public health significance among casual food sellers is undertaken in many resource-limited countries. we report the results of a survey in kiang west province, the gambia, and provide an exemplar methodology for such surveys in resource-limited laboratories. | 2015 | 25758855 |
| sequence conservation in the ancylostoma secreted protein-2 of necator americanus (na-asp-2) from hookworm infected individuals in thailand. | the ancylostoma secreted protein-2 of necator americanus (na-asp-2) was one of the promising vaccine candidates against the most prevalent human hookworm species as adverse vaccine reaction has compromised further human vaccine trials. to elucidate the gene structure and the extent of sequence diversity, we determined the complete nucleotide sequence of the na-asp-2 gene of individual larvae from 32 infected subjects living in 3 different endemic areas of thailand. sequence analysis revealed tha ... | 2012 | 22964044 |
| epidemiological investigation of parasitic infection of schoolchildren from six elementary schools in sakon nakhon province, thailand. | we conducted an epidemiological study of intestinal parasitic infection in 572 schoolchildren aged 4 to 12 years old from six elementary schools in sakon nakhon province, thailand from june 2013 to august 2014. we collected fecal, blood, and urine samples to investigate parasitic infection and conducted a questionnaire survey. soil samples were examined for egg contamination. fecal examination, using the formalin-ether sedimentation method, revealed that 39% of schoolchildren were infected with ... | 2017 | 28289269 |
| evaluation of anthelmintic potential of the ethiopian medicinal plant embelia schimperi vatke in vivo and in vitro against some intestinal parasites. | embelia schimperi has been used for the treatment of intestinal parasites especially tapeworm infestations for centuries in ethiopia. however, there is lack of scientific based evidences regarding the efficacy, safety and phytochemical analysis of this plant despite its frequent use as an anthelmintic. this study has therefore evaluated the efficacy and acute toxicity of e. schimperi thereby generating relevant preclinical information. | 2015 | 26084371 |
| regulatory monocytes in helminth infections: insights from the modulation during human hookworm infection. | while the macrophage polarization is well characterized in helminth infections, the natural heterogeneity of monocytes with multiple cell phenotypes might influence the outcome of neglected diseases, such hookworm infection. here, we report the profile of monocytes in human hookworm infections as a model to study the regulatory subpopulation of monocytes in helminth infections. | 2017 | 28390393 |
| water, sanitation and hygiene (wash) and environmental risk factors for soil-transmitted helminth intensity of infection in timor-leste, using real time pcr. | no investigations have been undertaken of risk factors for intensity of soil-transmitted helminth (sth) infection in timor-leste. this study provides the first analysis of risk factors for intensity of sth infection, as determined by quantitative pcr (qpcr), examining a broad range of water, sanitation and hygiene (wash) and environmental factors, among communities in manufahi district, timor-leste. | 2017 | 28346536 |
| epidemiology of polyparasitism with taenia solium, schistosomes and soil-transmitted helminths in the co-endemic village of malanga, democratic republic of congo. | helminth co-infections are common in sub-saharan africa. however, little is known about the distribution and determinants of co-infections with taenia solium taeniasis/cysticercosis. building on a previous community-based study on human cysticercosis in malanga village, we investigated co-infections with taenia solium, soil-transmitted helminths (sths) and schistosoma spp and associated risk factors in a random subsample of 330 participants. real time pcr assays were used to detect dna of soil-t ... | 2017 | 28336269 |
| advances in neglected tropical disease vaccines: developing relative potency and functional assays for the na-gst-1/alhydrogel hookworm vaccine. | a new generation of vaccines for the neglected tropical diseases (ntds) have now advanced into clinical development, with the na-gst-1/alhydrogel hookworm vaccine already being tested in phase 1 studies in healthy adults. the current manuscript focuses on the often overlooked critical aspects of ntd vaccine product development, more specifically, vaccine stability testing programs. a key measure of vaccine stability testing is "relative potency" or the immunogenicity of the vaccine during storag ... | 2017 | 28192438 |
| diagnosing polyparasitism in a high-prevalence setting in beira, mozambique: detection of intestinal parasites in fecal samples by microscopy and real-time pcr. | many different intestinal parasite species can co-occur in the same population. however, classic diagnostic tools can only frame a particular group of intestinal parasite species. hence, one or two tests do not suffice to provide a complete picture of infecting parasite species in a given population. the present study investigated intestinal parasitic infections in beira, mozambique, i.e. in the informal settlement of inhamudima. diagnostic accuracy of five classical microscopy techniques and re ... | 2017 | 28114314 |
| isothermal diagnostic assays for monitoring single nucleotide polymorphisms in necator americanus associated with benzimidazole drug resistance. | soil-transmitted helminths (sths) are the most prevalent intestinal helminths of humans, and a major cause of morbidity in tropical and subtropical countries. the benzimidazole (bz) drugs albendazole (abz) and mebendazole (mbz) are used for treatment of human sth infections and this use is increasing dramatically with massive drug donations. frequent and prolonged use of these drugs could lead to the emergence of anthelmintic resistance as has occurred in nematodes of livestock. previous molecul ... | 2016 | 27930648 |
| hookworm infection. | hookworms are soil-transmitted nematode parasites that can reside for many years in the small intestine of their human hosts; necator americanus is the predominant infecting species. adult worms feed on the blood of a host and can cause iron deficiency anaemia, especially in high-risk populations (children and women of childbearing age). almost 500 million people in developing tropical countries are infected, and simulation models estimate that hookworm infection is responsible for >4 million di ... | 2016 | 27929101 |
| molecular features of hookworm larvae (necator spp.) raised by coproculture from ugandan chimpanzees and gabonese gorillas and humans. | species composition of necator hookworms was surveyed in (i) ugandan chimpanzees living around farms and villages at bulindi, (ii) gabonese gorillas under habituation in moukalaba-doudou national park (mdnp), and (iii) gabonese villagers living adjacent to mdnp. internal transcribed spacers (its) of rdna and partial cytochrome c oxidase subunit 1 (cox1) gene of mtdna were analyzed from larvae obtained by coproculture. three its types (i, ii and iii) and three cox1 haplotype groups (a, b and c) w ... | 2017 | 27840196 |
| sequence data mining in search of hookworm (necator americanus) micrornas. | the new world hookworm, necator americanus is a soil-transmitted nematode responsible for necatoriasis (a type of helminthiasis) in hosts such as humans, dogs, and cats. n. americanus genome and transcriptome has been sequenced and a draft assembly analysis has been published highlighting protein coding genes and possible drug target proteins. hookworm microrna identification, annotations and their public release is yet to be attempted. the same is evident from lack of hookworm mirna information ... | 2016 | 27259664 |
| restoration of hookworm egg development after prolonged storage in stool suspension. | hookworm infection is still prevalent in southern thailand despite control measures. hookworm eggs submerged for an extended period under water from rainfall or in latrines may not survive, but they may recover their ability to develop into infective larvae when exposed to atmospheric air. this study examined the survival of the hookworm eggs in stool suspension and the restoration of development capability after prolonged storage. in stool mass, eggs developed normally and yielded infective fil ... | 2016 | 27053130 |
| advancing a vaccine to prevent hookworm disease and anemia. | a human hookworm vaccine is under development and in clinical trials in africa and the americas. the vaccine contains the na-apr-1 and na-gst-1 antigens. it elicits neutralizing antibodies that interfere with establishment of the adult hookworm in the gut and the ability of the parasite to feed on blood. the vaccine target product profile is focused on the immunization of children to prevent hookworm infection and anemia caused by necator americanus. it is intended for use in low- and middle-inc ... | 2016 | 27040400 |
| adult hookworms (necator spp.) collected from researchers working with wild western lowland gorillas. | in general, studies on the diversity of strongylid nematodes in endangered host species are complicated as material obtained by non-invasive sampling methods has limited value for generic and species identification. while egg morphology barely allows assignment to family, the morphology of cultivated infective third stage larvae provides a better resolution at the generic level but cannot be used for exact species identification. morphology-based taxonomic approaches greatly depend on the examin ... | 2016 | 26858023 |
| [one case of necator americanus infection found under gastroscope]. | | 2015 | 26672231 |
| pharmacological approaches in celiac disease. | celiac disease is an autoimmune enteropathy triggered by the ingestion of gluten, characterized by immune responses toward gluten constituents and the autoantigen transglutaminase 2. the only current treatment available for celiac disease is a gluten-free diet, however there are a plethora of therapies in development for the treatment of celiac disease (e.g. vaccine), management of symptoms while consuming gluten (e.g. necator americanus) or adjuvant therapies in conjunction with the gluten-free ... | 2015 | 26414923 |
| diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by na-far-1 from necator americanus. | fatty acid and retinol-binding proteins (fars) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. they are secreted into host tissues by parasites of plants, animals and humans. the structure of a far protein from the free-living nematode caenorhabditis elegans is available, but this protein [c. elegans far-7 (ce-far-7)] is from a subfamily of fars that does not appear to be important at the host/parasite interface. we have therefore examined [necato ... | 2015 | 26318523 |
| lipopeptide nanoparticles: development of vaccines against hookworm parasite. | necator americanus (hookworm) infects over half a billion people worldwide. anthelminthic drugs are commonly used to treat the infection; however, vaccination is a more favorable strategy to combat this parasite. we designed new b-cell peptide epitopes based on the aspartic protease of n. americanus (na-apr-1). the peptides were conjugated to self-adjuvanting lipid core peptide (lcp) systems via stepwise solid-phase peptide synthesis (spps) and copper catalyst azide-alkyne cycloaddition (cuaac) ... | 2015 | 26269385 |
| isolation, characterization, and anthelminthic activities of a novel dichapetalin and other constituents of dichapetalum filicaule. | dichapetalum filicaule breteler (dichapetalaceae) is a rare species occurring only in côte d'ivoire and ghana. although research on several species of the genus has produced interesting bioactive compounds, particularly the dichapetalins, a novel class of triterpenoids with antineoplastic properties, there is virtually no information on the ethnobotanical uses and chemical constituents of d. filicaule. | 2016 | 26118692 |
| obscure overt gastrointestinal bleeding due to necator americanus diagnosed by double-balloon enteroscopy. | | 2015 | 25926209 |
| expression, purification, and characterization of the necator americanus aspartic protease-1 (na-apr-1 (m74)) antigen, a component of the bivalent human hookworm vaccine. | over 400 million people living in the world's poorest developing nations are infected with hookworms, mostly of the genus necator americanus. a bivalent human hookworm vaccine composed of the necator americanus glutathione s-transferase-1 (na-gst-1) and the necator americanus aspartic protease-1 (na-apr-1 (m74)) is currently under development by the sabin vaccine institute product development partnership (sabin pdp). both monovalent vaccines are currently in phase 1 trials. both na-gst-1 and na- ... | 2015 | 25905574 |
| celiac disease 2015 update: new therapies. | celiac disease (cd) is a chronic, small intestinal, immune-mediated enteropathy triggered by exposure to dietary gluten in genetically susceptible individuals. currently, lifelong adherence to a gluten-free diet (gfd) is the only available treatment. however, gfd alone is not sufficient to relieve symptoms, control small intestinal inflammation and prevent long-term complications in many patients. the gfd has its challenges including issues related to adherence, lifestyle restrictions and cost. ... | 2015 | 25864708 |
| potential treatment of inflammatory bowel disease: a review of helminths therapy. | an inflammatory bowel disease (ibd) is most common in highly industrialized western countries but uncommon in less developed areas of the world where helminths are frequent. the hygiene hypothesis proposes that the recent increase in allergic and autoimmune diseases is due to modern highly hygienic life styles and medical conditions. loss of routine exposure to parasitic helminths, as a result of increasing lifestyle-associated factors, may be one factor leading to the increased disease prevalen ... | 2014 | 25436093 |
| optimization and revision of the production process of the necator americanus glutathione s-transferase 1 (na-gst-1), the lead hookworm vaccine recombinant protein candidate. | infection by the human hookworm necator americanus is a leading cause of anemia and disability in the developing countries of africa, asia, and the americas. in order to prevent childhood hookworm disease in resource poor settings, a recombinant vaccine is under development by the sabin vaccine institute and texas children's hospital center for vaccine development, a product development partnership (pdp). previously, we reported on the expression and purification of a highly promising hookworm v ... | 2014 | 25424799 |
| allergy and worms: let's bring back old friends? | in order to survive in their host, parasitic worms (helminths) have evolved cunning strategies to manipulate the host immune system, some of which may lead to protection from immune dysregulatory diseases such as allergy. thus, loss of exposure to helminths due to a highly hygienic life style might have contributed to the fact that living in an industrialized country is being associated with an increased prevalence of allergic diseases. however, it must be pointed out that certain helminth infec ... | 2014 | 25281198 |
| experimental hookworm infection and gluten microchallenge promote tolerance in celiac disease. | celiac disease (ced) is a common gluten-sensitive autoimmune enteropathy. a gluten-free diet is an effective treatment, but compliance is demanding; hence, new treatment strategies for ced are required. | 2015 | 25248819 |
| structure of glutathione s-transferase 1 from the major human hookworm parasite necator americanus (na-gst-1) in complex with glutathione. | glutathione s-transferase 1 from necator americanus (na-gst-1) is a vaccine candidate for hookworm infection that has a high affinity for heme and metal porphyrins. as part of attempts to clarify the mechanism of heme detoxification by hookworm gsts, co-crystallization and soaking studies of na-gst-1 with the heme-like molecules protoporphyrin ix disodium salt, hematin and zinc protoporphyrin were undertaken. while these studies did not yield the structure of the complex of na-gst-1 with any of ... | 2014 | 25195885 |
| probing of a human proteome microarray with a recombinant pathogen protein reveals a novel mechanism by which hookworms suppress b-cell receptor signaling. | na-asp-2 is an efficacious hookworm vaccine antigen. however, despite elucidation of its crystal structure and studies addressing its immunobiology, the function of na-asp-2 has remained elusive. we probed a 9000-protein human proteome microarray with na-asp-2 and showed binding to cd79a, a component of the b-cell antigen receptor complex. na-asp-2 bound to human b lymphocytes ex vivo and downregulated the transcription of approximately 1000 b-cell messenger rnas (mrnas), while only approximatel ... | 2015 | 25139017 |
| helminth therapy or elimination: epidemiological, immunological, and clinical considerations. | deworming is rightly advocated to prevent helminth-induced morbidity. nevertheless, in affluent countries, the deliberate infection of patients with worms is being explored as a possible treatment for inflammatory diseases. several clinical trials are currently registered, for example, to assess the safety or efficacy of trichuris suis ova in allergies, inflammatory bowel diseases, multiple sclerosis, rheumatoid arthritis, psoriasis, and autism, and the necator americanus larvae for allergic rhi ... | 2014 | 24981042 |
| impact of experimental hookworm infection on the human gut microbiota. | the interactions between gastrointestinal parasitic helminths and commensal bacteria are likely to play a pivotal role in the establishment of host-parasite cross-talk, ultimately shaping the development of the intestinal immune system. however, little information is available on the impact of infections by gastrointestinal helminths on the bacterial communities inhabiting the human gut. we used 16s rrna gene amplification and pyrosequencing to characterize, for the first time to our knowledge, ... | 2014 | 24795483 |
| helminth/parasite treatment of multiple sclerosis. | epidemiological studies suggest that autoimmune diseases, such as multiple sclerosis (ms), are less frequent in individuals who are helminth carriers. this observation has been tested in murine models of colitis, ms, type 1 diabetes and asthma. in each case, mice colonized with helminths show protection from disease. this apparent down-modulation of inflammatory response resulting from helminth infection has triggered interest in exploring the potential clinical efficacy of controlled helminth i ... | 2014 | 24744099 |
| humans and great apes cohabiting the forest ecosystem in central african republic harbour the same hookworms. | hookworms are important pathogens of humans. to date, necator americanus is the sole, known species of the genus necator infecting humans. in contrast, several necator species have been described in african great apes and other primates. it has not yet been determined whether primate-originating necator species are also parasitic in humans. | 2014 | 24651493 |
| probing the equatorial groove of the hookworm protein and vaccine candidate antigen, na-asp-2. | hookworm activation-associated secreted proteins can be structurally classified into at least three different groups. the hallmark feature of group 1 activation-associated secreted proteins is a prominent equatorial groove, which is inferred to form a ligand binding site. furthermore, a conserved tandem histidine motif is located in the centre of the groove and believed to provide or support a yet to be determined catalytic activity. here, we report three-dimensional crystal structures of na-asp ... | 2014 | 24631931 |
| genome of the human hookworm necator americanus. | the hookworm necator americanus is the predominant soil-transmitted human parasite. adult worms feed on blood in the small intestine, causing iron-deficiency anemia, malnutrition, growth and development stunting in children, and severe morbidity and mortality during pregnancy in women. we report sequencing and assembly of the n. americanus genome (244 mb, 19,151 genes). characterization of this first hookworm genome sequence identified genes orchestrating the hookworm's invasion of the human hos ... | 2014 | 24441737 |
| celiac disease as an autoimmune condition. | autoimmune diseases have become a major medical problem of recent years. celiac disease is an autoimmune disease model. the aim of our study was to follow the changes in the clinical autoimmunity picture of the celiac disease from recent years. the study of autoimmunity in celiac disease has focused on associated diseases with the aforementioned disease: type 1 diabetes mellitus, thyroid autoimmunity disease, graves' disease, hashimoto's disease, systemic lupus erythematosus, systemic sclerosis, ... | 2014 | 26155154 |
| structure of monomeric na-gst-3, a glutathione s-transferase from the major human hookworm parasite necator americanus. | necator americanus is the major cause of human hookworm infection, which is a global cause of anemia in the developing world. ongoing efforts to control hookworm infection include the identification of candidate vaccine antigens as well as potential therapeutic targets from the infective l3 larval stages and adult stages of the parasite. one promising family of proteins are the adult-stage-secreted cytosolic glutathione s-transferases (gsts). nematode gsts facilitate the inactivation and degrada ... | 2013 | 23908024 |
| hookworm infection among school age children in kintampo north municipality, ghana: nutritional risk factors and response to albendazole treatment. | children (n = 812) 6-11 years of age attending 16 schools in the kintampo north municipality of ghana were screened for participation in a study on hookworm infection, nutrition, and response to albendazole. the prevalence of necator americanus hookworm infection (n = 286) was 39.1%, and significant predictors of infection included age, malaria parasitemia, lack of health care, school area, levels of antibodies against hookworm, and low consumption of animal foods. the cure rate after a single d ... | 2013 | 23836564 |
| prerequisites for the pharmaceutical industry to develop and commercialise helminths and helminth-derived product therapy. | during the past 10 years, immunologists, epidemiologists and parasitologists have made many new exciting discoveries in the field of helminth-mediated immune regulation. in addition, many animal experiments have shown that certain helminths or products derived from helminths can protect mice from developing allergic or autoimmune disease. some clinical trials utilising trichuris suis or necator americanus for the treatment of allergic disorders and inflammatory bowel disease have been conducted. ... | 2013 | 23291462 |
| changed gluten immunity in celiac disease by necator americanus provides new insights into autoimmunity. | we recently completed clinical trials in people with diet-treated celiac disease who were purposefully infected with the ubiquitous human hookworm, necator americanus. hookworm infection elicited not only parasite-specific immunity but also modified the host's immune response to gluten. after infection, mucosal il-1β and il-22 responses were enhanced, but ifnγ and il-17a levels and circulating regulatory t cells following gluten challenge were suppressed, and the adaptive response to gluten acqu ... | 2013 | 23291460 |
| ¹h, ¹³c and ¹⁵n chemical shift assignments of na-far-1, a helix-rich fatty acid and retinol binding protein of the parasitic nematode necator americanus. | the fatty acid and retinol-binding (far) proteins are a family of unusual helix-rich lipid binding proteins found exclusively in nematodes, and are secreted by a range of parasites of humans, animals and plants. na-far-1 is from the parasitic nematode necator americanus, an intestinal blood-feeding parasite of humans. sequence-specific (1)h, (13)c and (15)n resonance assignments have been obtained for the recombinant 170 amino acid protein, using three-dimensional triple-resonance heteronuclear ... | 2014 | 23179061 |
| translatability of helminth therapy in inflammatory bowel diseases. | modern hygienic lifestyles are associated with the emergence of inflammatory bowel disease (ibd) which now afflicts millions of people in highly-developed countries. meticulous hygiene interrupts conduits of transmission required for ubiquitous exposure to parasitic worms (helminths). we proposed that loss of exposure to helminths permits development of ibd. early clinical trials suggested that exposure to helminths such as trichuris suis or necator americanus can improve ibd. over the last seve ... | 2013 | 23178819 |
| where are we on worms? | there is something about living in an industrialized country that dramatically increases the risk of acquiring inflammatory bowel disease (ibd). loss of routine exposure to parasitic worms (helminths), due to modern highly hygienic life styles, likely contributes to this risk. this article reviews current understanding on how helminths influence intestinal inflammation and mucosal immune responses. | 2012 | 23079675 |
| effects of treatment on ige responses against parasite allergen-like proteins and immunity to reinfection in childhood schistosome and hookworm coinfections. | naturally occurring human immunity to both schistosomiasis and hookworm infection has been associated with ige responses against parasite allergen-like proteins. since the two helminths frequently coinfect the same individuals, there is growing advocacy for their concurrent treatment. however, both helminths are known to exert strong immunomodulatory effects; therefore, coinfected individuals could have immune responses different from those characteristically seen in monoinfected individuals. in ... | 2013 | 23071136 |
| modelling the ecological niche of hookworm in brazil based on climate. | the distribution of hookworm in schistosomiasis-endemic areas in brazil was mapped based on climate suitability. known biological requirements of hookworm were fitted to data in a monthly long-term normal climate grid (18 x 18 km) using geographical information systems. hookworm risk models were produced using the growing degree day (gdd) water budget (wb) concept. a moisture-adjusted model (ma-gdd) was developed based on accumulation of monthly temperatures above a base temperature of 15 °c (be ... | 2012 | 23032277 |
| parasitic infections and immune function: effect of helminth infections in a malaria endemic area. | according to the hygiene hypothesis, reduced exposure to infections could explain the rise of atopic diseases in high-income countries. helminths are hypothesised to alter the host's immune response in order to avoid elimination and, as a consequence, also reduce the host responsiveness to potential allergens. to elucidate the effect of current helminth infections on immune responsiveness in humans, we measured cytokine production in a rural ghanaian population in an area with multiple endemic p ... | 2013 | 22999162 |
| two crystal forms of a helix-rich fatty acid- and retinol-binding protein, na-far-1, from the parasitic nematode necator americanus. | na-far-1 is an unusual α-helix-rich fatty acid- and retinol-binding protein from necator americanus, a blood-feeding intestinal parasitic nematode of humans. it belongs to the far protein family, which is unique to nematodes; no structural information is available to date for far proteins from parasites. crystals were obtained with two different morphologies that corresponded to different space groups. crystal form 1 exhibited space group p432 (unit-cell parameters a = b = c = 120.80 å, α = β = ... | 2012 | 22750878 |
| fusion of na-asp-2 with human immunoglobulin fcγ abrogates histamine release from basophils sensitized with anti-na-asp-2 ige. | na-asp-2 is a major protein secreted by infective third-stage larvae (l3) of the human hookworm necator americanus upon host entry. it was chosen as a lead vaccine candidate for its ability to elicit protective immune responses. however, clinical development of this antigen as a recombinant vaccine was halted because it caused allergic reactions among some of human volunteers previously infected with n. americanus. to prevent ige-mediated allergic reactions induced by na-asp-2 but keep its immun ... | 2012 | 22651670 |
| generalized urticaria induced by the na-asp-2 hookworm vaccine: implications for the development of vaccines against helminths. | necator americanus ancylostoma-secreted protein 2 (na-asp-2) is secreted by infective hookworm larvae on entry into human hosts. vaccination of laboratory animals with recombinant na-asp-2 provides significant protection against challenge infections. in endemic areas antibodies to na-asp-2 are associated with reduced risk of heavy n americanus infections. | 2012 | 22633322 |
| helminth therapy (worms) for allergic rhinitis. | allergic rhinitis is a disorder of the nasal membranes and surrounding tissues, and a worldwide cause of illness and disability. helminths are complex tissue-dwelling or lumen-dwelling organisms that inhabit larger organisms and are frequently asymptomatic. helminths modulate the natural immune responses of their human hosts, and may prevent or cure immune-mediated or allergic diseases (e.g. allergic rhinitis) in the host. non-randomised studies support this hypothesis. | 2012 | 22513973 |
| expression, purification, and molecular analysis of the necator americanus glutathione s-transferase 1 (na-gst-1): a production process developed for a lead candidate recombinant hookworm vaccine antigen. | the enzyme necator americanus glutathione s-transferase 1 (na-gst-1) belongs to a unique nu class of gsts and is a lead candidate antigen in a bivalent human hookworm vaccine. here we describe the expression of na-gst-1 in the yeast pichia pastoris at the 20 l manufacturing scale and its purification process performed by three chromatographic steps, comprised of a q sepharose xl anion exchange column, followed by a butyl sepharose hp hydrophobic affinity column and a superdex 75 size-exclusion c ... | 2012 | 22503665 |
| advances in vaccines against neglected tropical diseases: enhancing physical stability of a recombinant hookworm vaccine through biophysical and formulation studies. | a bivalent recombinant vaccine for human hookworm disease is under development. one of the lead candidate antigens in the vaccine is a glutathione s-transferase cloned from the hookworm necator americanus (na-gst-1) which is expressed in the yeast pichia pastoris. based on preliminary studies demonstrating that the recombinant protein was not stable in an acetate buffer at ph 6, we undertook an extensive stability analysis of the molecule. to improve and optimize stability we complemented tradit ... | 2012 | 22495115 |
| the role of ilc2 in hookworm infection. | hookworm is a major public health concern, with around 500 million people affected worldwide (1). still, relatively little is known about the immunological responses involved in human infection. animal studies are mainly confined to using the natural rodent helminth nippostrongylus brasiliensis, as this has been proposed as the most accurate model of hookworm infection in the mouse, with both its lifecycle, and the immune responses it invokes having been extremely well characterized. in this rev ... | 2017 | 28369954 |
| the diversity and impact of hookworm infections in wildlife. | hookworms are blood-feeding nematodes that parasitize the alimentary system of mammals. despite their high pathogenic potential, little is known about their diversity and impact in wildlife populations. we conducted a systematic review of the literature on hookworm infections of wildlife and analyzed 218 studies qualitative and quantitatively. at least 68 hookworm species have been described in 9 orders, 24 families, and 111 species of wild mammals. black bears, red foxes, and bobcats harbored t ... | 2017 | 28765810 |
| using a health-rating system to evaluate the usefulness of caenorhabditis elegans as a model for anthelmintic study. | soil-transmitted helminths (sths) are intestinal parasitic nematodes that infect humans, and are transmitted through contaminated soil. these nematodes include the large roundworm (ascaris lumbricoides), whipworm (trichuris trichiura), and hookworm (ancylostoma ceylanicum, ancylostoma duodenale, and necator americanus). nearly 1.5 billion people (~24% of the population) worldwide are infected with at least one species of these parasites, burdening the poor, in particular, children and pregnant w ... | 2017 | 28632749 |
| efficacy of single-dose 500 mg mebendazole in soil-transmitted helminth infections: a review. | soil-transmitted helminthiasis (sth) is caused by ascaris lumbricoides (roundworm), trichuris trichiura (whipworm), and ancylostoma duodenale and necator americanus (hookworms). mebendazole is one of the recommended preventive chemotherapy agents for sth. this review summarizes the efficacy data from 29 studies with single-dose 500 mg mebendazole in sth treatment and compares the results with those of a recently conducted phase 3 study of a 500 mg mebendazole chewable tablet against a. lumbricoi ... | 2017 | 28716158 |
| an integrated study of human and animal infectious disease in the lake victoria crescent small-holder crop-livestock production system, kenya. | the neglected zoonotic diseases (nzd) are an understudied group that are a major cause of illness throughout the developing world. in general, little is known about the prevalence and burden of nzds in affected communities, particularly in relation to other infectious diseases with which they are often co-endemic. we describe the design and descriptive epidemiological outputs from an integrated study of human and animal zoonotic and non-zoonotic disease in a rural farming community in western ke ... | 2017 | 28666412 |
| hookworm infections among migrant workers in malaysia: molecular identification of necator americanus and ancylostoma duodenale. | ongoing urbanisation of the working population as well as cross-border migration of workers particularly into large cities has contributed to the development and growth of urban slums. these deprived areas are conducive for the transmission of intestinal pathogens including hookworm. the aim of this study was to determine both the prevalence and species identity of hookworm infections among the migrant worker community in malaysia. a total of 388 faecal samples were collected from migrant worker ... | 2017 | 28610937 |
| hookworm infection is associated with decreased cd4+ t cell counts in hiv-infected adult ugandans. | most studies evaluating epidemiologic relationships between helminths and hiv have been conducted in the pre-art era, and evidence of the impact of helminth infections on hiv disease progression remains conflicting. less is known about helminth infection and clinical outcomes in hiv-infected adults receiving antiretroviral therapy (art). we sampled hiv-infected adults for eight gastrointestinal parasites and correlated parasitic infection with demographic predictors, and clinical and immunologic ... | 2017 | 28542260 |
| an environmental assessment and risk map of ascaris lumbricoides and necator americanus distributions in manufahi district, timor-leste. | in timor-leste there have been intermittent and ineffective soil-transmitted helminth (sth) deworming programs since 2004. in a resource-constrained setting, having information on the geographic distribution of sth can aid in prioritising high risk communities for intervention. this study aimed to quantify the environmental risk factors for sth infection and to produce a risk map of sth in manufahi district, timor-leste. | 2017 | 28489889 |