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cryptosporidium and host resistance: historical perspective and some novel approaches.cryptosporidium parvum is recognized as a major cause of diarrheal disease in neonatal bovine calves. in addition, this protozoan parasite has emerged as an important cause of disease in both immunocompromised and immunocompetent humans. despite years of research, no consistently effective means of prevention or treatment are readily available for cryptosporidiosis in any species. infection through ingestion of contaminated water has been widely documented; c. parvum was reported to be responsib ...200312885209
the homologous and interspecies transmission of cryptosporidium parvum and cryptosporidium meleagridis.experimental infections have been performed in several mammals and birds to determine the host's specificity for cryptosporidium parvum (of human and bovine origin) and for cryptosporidium meleagridis (isolated from broiler chicken). the c. parvum infection (of human origin) was established also in calves (bos taurus), lambs (ovis aries), mice (mus musculus), and rats (ratus norvegicus), but not in broiler chickens (gallus domestica). the c. parvum infection (of bovine origin), was achieved in c ...200314510055
long-term study of cryptosporidium prevalence on a lowland farm in the united kingdom.a longitudinal sample survey testing for cryptosporidium in livestock and small wild mammals conducted over 6 years (1992-1997) on a lowland farm in warwickshire, england, has shown the parasite to be endemic and persistently present in all mammalian categories. faecal samples were taken throughout the year and oocysts concentrated by a formal ether sedimentation method for detection by immunofluorescence staining using a commercially available genus specific monoclonal antibody. cryptosporidium ...200314519315
multilocus genotyping of cryptosporidium parvum type 2: population genetics and sub-structuring.cryptosporidium parvum is an intracellular protozoan parasite that infects the gastrointestinal tract of humans and other mammals. it has significant economic importance as a pathogen of livestock and, as there is no effective treatment or vaccine available, understanding transmission routes and identifying sources of infection is key to preventing future outbreaks and controlling this disease. in this study we have determined the multilocus genotype (mlg) of 240 c. parvum type 2 (bovine) isolat ...200314522184
influence of surface characteristics on the stability of cryptosporidium parvum oocysts.microelectrophoresis is a common technique for probing the surface chemistry of the cryptosporidium parvum oocyst. results of previous studies of the electrophoretic mobility of c. parvum oocysts in which microelectrophoresis was used are incongruent. in this work we demonstrated that capillary electrophoresis may also be used to probe the surface characteristics of c. parvum oocysts, and we related the surface chemistry of c. parvum oocysts to their stability in water. capillary electrophoresis ...200312839749
effect of organic acids and hydrogen peroxide on cryptosporidium parvum viability in fruit juices.cryptosporidium parvum has historically been associated with waterborne outbreaks of diarrheal illness. foodborne cryptosporidiosis has been associated with unpasteurized apple cider. infectious oocysts are shed in the feces of common ruminants like cattle and deer in and near orchards. in this study, the ability of organic acids and hydrogen peroxide (h2o2) added to fruit juice to inhibit the survival of c. parvum was analyzed. oocyst viability was analyzed by a cell culture infectivity assay w ...200314503720
aids-associated diarrhea and wasting in northeast brazil is associated with subtherapeutic plasma levels of antiretroviral medications and with both bovine and human subtypes of cryptosporidium parvum.advanced hiv infection is frequently complicated by diarrhea, disruption of bowel structure and function, and malnutrition. resulting malabsorption of or pharmacokinetic changes in antiretroviral agents might lead to subtherapeutic drug dosing and treatment failure in individual patients, and could require dose adjustment and/or dietary supplements during periods of diarrheal illness. we determined the plasma levels of antiretroviral medications in patients that had already been started on medic ...200312807688
viability and infectivity of cryptosporidium parvum oocysts detected in river water in hokkaido, japan.the viability and infectivity of cryptosporidium parvum (c. parvum) oocysts, detected in water samples collected from river water in hokkaido, were investigated using severe combined immunodeficient (scid) mice. the water samples collected from september 27 through october 10, 2001 by filtration using cuno cartridge filters were purified and concentrated by the discontinuous centrifugal flotation method. from 1.2 x 10 (5) liters of the raw river water, approximately 2 x 10(4) oocysts were obtain ...200312808210
prophylactic use of decoquinate for infections with cryptosporidium parvum in experimentally challenged neonatal calves.to evaluate the effect of daily oral administration of decoquinate to neonatal calves experimentally challenged with various numbers of cryptosporidium parvum oocysts.200314507102
comparison of selected diagnostic methods for identification of cryptosporidium parvum and cryptosporidium andersoni in routine examination of faeces.this study involved the comparison of suitability of different methods for routine diagnostics of cryptosporidium spp. two staining methods, one concentration-sedimentation method, seven concentration-floatation methods and one combined floatation-sedimentation method were compared. the methods were tested with two concentrations (1 x 10(5) and 1 x 10(6)/g) of c. parvum and c. andersoni. the methods were evaluated using light microscope, magnification 400x for concentration methods and 1000x for ...200314633212
identification of genotypically mixed cryptosporidium parvum populations in humans and calves.genotypic analyses of cryptosporidium parvum oocysts have divided the species into two genotypes, referred to as type 1 and type 2. although humans are susceptible to both types, mixed type 1/type 2 infections have rarely been identified. the paucity of mixed infections could be explained by the predominance of one type over the other in mixed infections, or by the poor sensitivity of restriction fragment length polymorphism (rflp) analyses for detecting subpopulations. using a type-specific rea ...200314550892
anticryptosporidial activity of furan derivative g1 and its inclusion complex with beta-cyclodextrin.the capacity of beta-cyclodextrin (betacd) to form a complex with a new furanic derivative, g1, was investigated. interactions of the drug and betacd in solution and in the solid state were studied using phase solubility techniques, thermal methods, x-ray, and ir spectroscopy. preparation of a kneaded mix of g1/betacd increased both the aqueous solubility and the dissolution rate of the furan derivative. the anticryptosporidial efficacies of the drug and of the inclusion complex were evaluated u ...200414648649
genetic diversity of cryptosporidium spp. in captive reptiles.the genetic diversity of cryptosporidium in reptiles was analyzed by pcr-restriction fragment length polymorphism and sequence analysis of the small subunit rrna gene. a total of 123 samples were analyzed, of which 48 snake samples, 24 lizard samples, and 3 tortoise samples were positive for cryptosporidium: nine different types of cryptosporidium were found, including cryptosporidium serpentis, cryptosporidium desert monitor genotype, cryptosporidium muris, cryptosporidium parvum bovine and mou ...200414766569
detection of antibodies to a recombinant cryptosporidium parvum p23 in serum and feces from neonatal calves.passive transfer of maternal antibodies via colostrum is important to protect newborn ruminants against microbial pathogens. in this study, 10 sets of calf serum, a sample of the colostrum fed to the calf, and serial fecal samples through the first 6 days after birth were collected from arbitrarily selected newborn holstein heifers. a recombinant cryptosporidium parvum p23, termed rc7, was used to determine whether anti-c. parvum antibodies can be detected in clinically normal neonates. the resu ...200314627138
identification of cryptosporidium parvum 'cattle' genotype from a severe outbreak of neonatal foal diarrhoea. 200314653344
new method using sedimentation and immunomagnetic separation for isolation and enumeration of cryptosporidium parvum oocysts and giardia lamblia cysts.a new method for the isolation of cryptosporidium parvum oocysts and giardia lamblia cysts from biosolid samples has been developed that utilizes sedimentation and immunomagnetic separation. the method was used to recover stained cysts and oocysts (spike organisms) from primary settled sewage sludge, anaerobically digested sewage sludge, and bovine manure. recovery efficiencies associated with this method were approximately 40 to 60% and were significantly greater than those associated with simi ...200314602637
first record of cryptosporidium infection in a raccoon dog (nyctereutes procyonoides viverrinus).cryptosporidium species have been found in more than 150 species of mammals, but there has been no report in raccoon dogs. here we found the cryptosporidium organism in a raccoon dog, nyctereutes procyonoides viverrinus, and identified this isolate using pcr-based diagnostic methods. cryptosporidium diagnostic fragments of the 18s ribosomal rna, cryptosporidium oocyst wall protein and 70-kda heat shock protein genes were amplified from the isolate and sequenced to reveal the phylogenetic relatio ...200415041092
prevalence of cryptosporidiosis among the villagers and domestic animals in several rural areas of korea.the present study was undertaken to investigate the infection status of cryptosporidium parvum in the villagers and the reservoir hosts in several rural areas in korea. a total 5,262 fecal samples were collected from the inhabitants residing at gangwon-do, chungcheongbuk-do, jeollanam-do, and gyeongsangnam-do between the dates of september, 2001 to june, 2002. in addition, 1,453 fecal samples were collected from livestock reared in gokseong-gun, jeollanam-do and chungju-si, chungcheongbuk-do. al ...200415060334
lack of detectable shedding of cryptosporidium parvum oocysts by periparturient dairy cattle.we examined whether periparturient dairy cattle shed cryptosporidium parvum oocysts within 12 hr of calving on 3 commercial dairy farms endemic for calfhood cryptosporidiosis. using a diagnostic method that can detect as few as 1 oocyst per gram of feces, we found no evidence of c. parvum oocysts in 86 fecal samples collected within 12 hr of calving from 43 dairy cows.200314740916
detection and molecular characterization of cryptosporidium spp. isolated from diarrheic children in switzerland.the prevalence of cryptosporidium spp. in diarrheic immunocompetent children living in switzerland was 5.5% (15 of 273). infection rates increased significantly with age. anthroponotic cryptosporidium hominis was identified in 11 children, 9 with a travel history. the zoonotic cryptosporidium parvum bovine genotype was identified in 3 children (2 without travel history). hence transmission of cryptosporidium spp. is primarily of anthroponotic nature in the study area.200415071295
cryptosporidium parvum and giardia intestinalis in calf diarrhoea in sweden.the objective of this study conducted in 75 herds was to investigate the presence and significance of criptosporidium parvum and giardia intestinalis in swedish dairy calves in comparison with rotavirus, coronavirus and escherichia coli k99+. the farmers were asked to collect faecal samples from each heifer calf that had diarrhoea between birth and 90 days of age, and also from a healthy calf of the same age. in total, 270 samples were collected and analysed. c. parvum, either alone or together ...200315074627
increased susceptibility of beta7-integrin-deficient neonatal mice in the early stage of cryptosporidium parvum infection.numerous inflammatory cells are recruited in response to cryptosporidium parvum infection. these cells include interferon gamma-producing t lymphocytes, which are of major importance for the resolution of infection. here, we show that beta7 integrin is not essential for the control of infection in mice but that beta7-deficient neonatal mice are more susceptible during the early stages of infection.200415155674
update on cryptosporidium and giardia infections in cattle. 200415099558
the sensitivity of pcr detection of cryptosporidium oocysts in fecal samples using two dna extraction methods.the implementation of cost-effective intervention strategies for zoonotic protozoa relies on the development of sensitive and accurate diagnostic methods. we carried out a study to evaluate the accuracy of a pcr method for the detection of cryptosporidium spp. oocysts in fecal samples from cattle.200315068384
cryptodb: the cryptosporidium genome resource.cryptodb (http://cryptodb.org) represents a collaborative effort to locate all genome data for the apicomplexan parasite cryptosporidium parvum in a single user-friendly database. cryptodb currently houses the genomic sequence data for both the human type 1 h strain and the bovine type 2 iowa strain in addition to all other available est and gss sequences obtained from public repositories. all data are available for data mining via blast, keyword searches of pre-computed blastx results and user- ...200414681426
intron-containing beta-tubulin transcripts in cryptosporidium parvum cultured in vitro.the genome of cryptosporidium parvum contains a relatively small number of introns, which includes the beta-tubulin gene with only a single intron. recently, it was observed that the intron was not removed from some of the beta-tubulin transcripts in the late life cycle stages cultured in vitro. although normally spliced beta-tubulin mrna was detected in all parasite intracellular stages by rt-pcr (e.g. hct-8 or caco-2 cells infected with c. parvum for 12-72 h), at 48-72 h post-infection unproce ...200415133080
neonatal-mouse infectivity of intact cryptosporidium parvum oocysts isolated after optimized in vitro excystation.we reexamined the finding of neumann et al. that intact cryptosporidium parvum oocysts obtained after in vitro excystation were infectious for neonatal cd-1 mice. we used both established excystation protocols and our own protocol that maximized excystation. although intact oocysts isolated after any of three protocols were infectious for neonatal cd-1 mice, the infectivity of intact oocysts isolated with our optimized excystation protocol was significantly lower than the infectivity of intact o ...200414711704
differential expression and interaction of transcription co-activator mbf1 with tata-binding protein (tbp) in the apicomplexan cryptosporidium parvum.all gene-specific transcriptional activators initiate gene transcriptions by binding to promoter sequences and recruiting general transcription factors including tata-binding protein (tbp) to upstream of targeted genes. some of them require multiprotein bridging factors (mbfs); for example, the type 1 mbf (mbf1) which interconnects the gene activator with tbp. in this study, the properties of a previously cloned type 1 multiprotein bridging factor (cpmbf1) and a newly identified tbp (cptbp1) fro ...200415133082
release of cryptosporidium and giardia from dairy cattle manure: physical factors.various physical factors affecting the release rate of naturally occurring cryptosporidium parvum oocysts and giardia duodenalis cysts from dairy manure disks to sprinkled water were studied. the investigated factors included temperature (5 or 23 degrees c), manure type (calf manure, a 50% calf and 50% cow manure mixture, and a 10% calf and 90% cow manure mixture), and water application method (mist or drip) and flow rate. effluent concentrations of manure and (oo)cysts were always several order ...200415254132
complete development of cryptosporidium parvum in host cell-free culture.the present study describes the complete in vitro development of cryptosporidium parvum (cattle genotype) in rpmi-1640 maintenance medium devoid of host cells. this represents the first report in which cryptosporidium is shown to multiply, develop and complete its life cycle without the need for host cells. furthermore, cultivation of cryptosporidium in diphasic medium consisting of a coagulated new born calf serum base overlaid with maintenance medium greatly increased the total number of crypt ...200415157759
prevalence and age-related variation of cryptosporidium species and genotypes in dairy calves.fifteen dairy farms in seven states on the east coast of the us were each visited on two consecutive years to determinate the prevalence of cryptosporidium species in pre-weaned (5 days to 2 months) and post-weaned calves (3-11 months), respectively. after each of 971 fecal specimens collected directly from each calf was sieved and subjected to density gradient centrifugation to remove debris and concentrate oocysts, specimens were examined by immunofluorescence microscopy, and polymerase chain ...200415177715
cryptosporidium parvum and giardia lamblia recovered from flies on a cattle farm and in a landfill.filth flies associated with a cattle barn and a municipal landfill were tested positive by combined immunofluorescent antibody and fluorescent in situ hybridization for cryptosporidium parvum and giardia lamblia on their exoskeletons and in their guts. more pathogens were carried by flies from the cattle barn than from the landfill; 81% of c. parvum and 84% of g. lamblia pathogens were presumptively viable.200415184182
sporadic cryptosporidiosis case-control study with genotyping.we report a case-control study of sporadic cryptosporidiosis with genotyping of isolates from case-patients. a postal questionnaire was completed by 427 patients and 427 controls. we obtained genotyping data on isolates from 191 patients; 115 were cryptosporidium hominis, and 76 were c. parvum. when all cryptosporidiosis cases were analyzed, three variables were strongly associated with illness: travel outside the united kingdom, contact with another person with diarrhea, and touching cattle. ea ...200415324544
cryptosporidium parvum attachment to and internalization by human biliary epithelia in vitro: a morphologic study.to explore the mechanisms by which cryptosporidium parvum infects epithelial cells, we performed a detailed morphological study by serial electron microscopy to assess attachment to and internalization of biliary epithelial cells by c. parvum in an in vitro model of human biliary cryptosporidiosis. when c. parvum sporozoites initially attach to the host cell membrane, the rhoptry of the sporozoite extends to the attachment site; both micronemes and dense granules are recruited to the apical comp ...200415165040
cryptosporidium suis n. sp. (apicomplexa: cryptosporidiidae) in pigs (sus scrofa).molecular and biological characteristics of a new species of cryptosporidium from the feces of pigs (sus scrofa) is described. oocysts are structurally indistinguishable from those of cryptosporidium parvum; they are passed fully sporulated, lack sporocysts, and measure 4.9-4.4 microm (mean = 4.6 microm) x 4.0-4.3 microm (mean = 4.2 microm); length to width ratio 1.1 (n = 50). cryptosporidium suis is not transmissible to nude mice and is poorly infectious for cattle. molecular and phylogenetic a ...200415357067
molecular epidemiology of giardia and cryptosporidium infections in dairy calves originating from three sources in western australia.a longitudinal study was undertaken to determine the spread of naturally acquired giardia and cryptosporidium in dairy cattle in western australia. samples were collected weekly from birth to weaning, and only calves that were sampled four or more times were included in the analysis. it was found that calves rapidly acquire infections with cryptosporidium parvum and giardia, with cryptosporidium being the first to appear within 1-3 weeks after birth whereas giardia was most prevalent in calves 4 ...200415265565
genotype and animal infectivity of a human isolate of cryptosporidium parvum in the republic of korea.cryptosporidium parvum oocysts were isolated from a child suffering from acute gastroenteritis and successfully passaged in a calf and mice (designated hereafter snu-h1) in the republic of korea; its molecular genotype has been analyzed. the gag microsatellite region was amplified by a polymerase chain reaction (pcr), with a 238 base pair product, which is commonly displayed in c. parvum. the isolate was shown to be a mixture of the genotypes 1 (anthroponotic) and 2 (zoonotic). to study its infe ...200415181350
host cell tropism underlies species restriction of human and bovine cryptosporidium parvum genotypes.it has been recognized recently that human cryptosporidiosis is usually caused by cryptosporidium parvum genotype i ("human" c. parvum), which is not found in animals. compared to c. parvum genotype ii, little is known of the biology of invasion of the human-restricted c. parvum genotype i. the aims of the present study were (i) to explore and compare with genotype ii the pathogenesis of c. parvum genotype i infection by using an established in vitro model of infection and (ii) to examine the po ...200415385517
evaluation of two rapid assays for detecting cryptosporidium parvum in calf feces.to evaluate 2 rapid, patient-side assays for detection of cryptosporidium parvum in feces from neonatal calves with diarrhea.200415515989
immunolocalization of an enterotoxic glycoprotein exoantigen on the secretory organelles of cryptosporidium parvum sporozoites.in this study, the fine ultrastructures of the secretory organelles of c. parvum sporozoites were demonstrated using transmission electron microscopy (tem). meanwhile, a previously identified enterotoxic 18-20 kda copro-antigen (18-20 kda cca), associated with cryptosporidiosis in both human and calves, was isolated and immunolocalized on c. parvum sporozoites. using immunoelectron microscopy and anti-18-20 kda monospecific antibody demonstrated marked existence of the 18-20 kda cca on the apica ...200415224585
epidemiologic and environmental investigation of a recreational water outbreak caused by two genotypes of cryptosporidium parvum in ohio in 2000.in august 2000, the ohio department of health requested assistance to investigate a cryptosporidiosis outbreak with more than 700 clinical case-patients. an epidemiologic and environmental investigation was conducted. stool specimens, pool water, and sand filter samples were analyzed. a community-based case-control study showed that the main risk factor was swimming in pool a (odds ratio [or] = 42, 95% confidence interval [ci] = 12.3-144.9). this was supported by results of polymerase chain reac ...200415569788
molecular genetic characterization and subcellular localization of a putative theileria annulata membrane protein.a theileria annulata protein (tad) exhibiting an n-terminal signal sequence for endoplasmic reticulum membrane translocation and a conserved cysteine-rich region was isolated by screening the mrna of a t. annulata-infected bovine lymphoblastoid cell line with degenerated primers directed against t. annulata-targeting sequences. the tad-coding sequence was found to be most closely related to the genomic dna sequence of t. parva (tigr database, 72%) and the amino acid sequence of plasmodium falcip ...200415490238
protection of calves against cryptosporiosis by oral inoculation with gamma-irradiated cryptosporidium parvum oocysts.the purpose of this study was to determine whether gamma-irradiated cryptosporidium parvum oocysts could elicit protective immunity against cryptosporidiosis in dairy calves. cryptosporidium parvum iowa strain oocysts (1 x 10(6) per inoculation) were exposed to various levels of gamma irradiation (350-500 gy) and inoculated into 1-day-old dairy calves. the calves were examined daily for clinical signs of cryptosporidiosis, and fecal samples were processed for the presence of c. parvum oocysts. a ...200415562625
microbial adhesion of cryptosporidium parvum sporozoites: purification of an inhibitory lipid from bovine mucosa.cryptosporidium parvum is a protozoan pathogen of humans and livestock worldwide. its ability to infect a wide range of species raises questions as to the involvement of a specific host cell receptor for parasite-host recognition. to investigate the mechanism of parasite-host cell recognition, we have developed an in vitro cell suspension binding assay to investigate adhesion of c. parvum sporozoites to host cells. morphologic features of binding events observed with this assay were identical to ...200415562596
cryptosporidiosis: an update in molecular epidemiology.molecular tools have been developed to detect and differentiate cryptosporidium at the species/genotype and subtype levels. these tools have been increasingly used in the characterization of the transmission of cryptosporidium spp. this review addresses the most recent developments in molecular epidemiology of cryptosporidiosis.200415353969
health sequelae of human cryptosporidiosis in immunocompetent patients.there have been no systematic studies following up the longer term health effects of cases of cryptosporidiosis for which genotype data exist.200415356813
[is cryptosporidium a zoonotic agent?].13 species and several genotypes have been described so far within the genus cryptosporidium. all of them have very small stages which makes morphological differentiation difficult. the most common species is c. parvum, an enteric pathogen with a broad host spectrum including man and domestic mammals. molecular biological studies on isolates of c. parvum and other species have shown that the species is likely not to be monophyletic but consists of several species with different host spectra. bas ...200415683036
development of procedures for direct extraction of cryptosporidium dna from water concentrates and for relief of pcr inhibitors.extraction of high-quality dna is a key step in pcr detection of cryptosporidium and other pathogens in environmental samples. currently, cryptosporidium oocysts in water samples have to be purified from water concentrates before dna is extracted. this study compared the effectiveness of six dna extraction methods (dna extraction with the qiaamp dna minikit after oocyst purification with immunomagnetic separation and direct dna extraction methods using the fastdna spin kit for soil, qiaamp dna s ...200515746310
efficacy of vegetated buffer strips for retaining cryptosporidium parvum.overland and shallow subsurface hydrologic transport of pathogenic cryptosporidium parvum oocysts from cattle feces into surface drinking water supplies is a major concern on annual grasslands in california's central and southern sierra nevada foothills. soil boxes (0.5 m wide x 1.1 m long x 0.3 m deep) were used to evaluate the ability of grass vegetated buffer strips to retain 2 x 10(8) spiked c. parvum oocysts in 200-g fecal deposits during simulated rainfall intensities of 30 to 47.5 mm/h ov ...200415537947
present and future control of cryptosporidiosis in humans and animals.although water treatment processes to remove cryptosporidium are improving and detection methods for identifying the parasite in water are becoming more sensitive, outbreaks of cryptosporidiosis continue in the human population. animals, especially dairy calves, often become infected as c. parvum oocysts are present in high numbers, remain viable for long periods of time after excretion and no disinfectants, prophylactic or therapeutic reagents exist. vaccination against c. parvum is being attem ...200415606351
detection of cryptosporidium and identification to the species level by nested pcr and restriction fragment length polymorphism.cryptosporidiosis is an emerging protozoan disease associated with large waterborne outbreaks. diagnosis relies on microscopic examination of stools, but this method cannot identify the infecting species of cryptosporidium. we have developed a test based on nested pcr and restriction fragment length polymorphism (rflp) that offers simple identification of cryptosporidium hominis, cryptosporidium parvum, and most other human infective species in stool samples. purified c. parvum oocysts were used ...200515750054
fate of pathogens present in livestock wastes spread onto fescue plots.fecal wastes from a variety of farmed livestock were inoculated with livestock isolates of escherichia coli o157, listeria monocytogenes, salmonella, campylobacter jejuni, and cryptosporidium parvum oocysts at levels representative of the levels found in naturally contaminated wastes. the wastes were subsequently spread onto a grass pasture, and the decline of each of the zoonotic agents was monitored over time. there were no significant differences among the decimal reduction times for the bact ...200515691918
direct comparison of selected methods for genetic categorisation of cryptosporidium parvum and cryptosporidium hominis species.a study was undertaken to compare the performance of five different molecular methods (available in four different laboratories) for the identification of cryptosporidium parvum and cryptosporidium hominis and the detection of genetic variation within each of these species. the same panel of oocyst dna samples derived from faeces (n=54; coded blindly) was sent for analysis by: (i) dna sequence analysis of a fragment of the hsp70 gene; (ii) dna sequence analysis and the ssrrna gene in laboratory ...200515777916
outbreaks of enteric infections caused by multiple pathogens associated with calves at a farm day camp.transmission of enteric pathogens at venues where the public contacts farm animals is a growing problem, particularly among children. in 2000 and again in 2001, enteric illness outbreaks caused by multiple pathogens occurred at a farm day camp for children in minnesota.200415626945
the effect of thermal treatments on the viability and infectivity of cryptosporidium parvum on beef surfaces.the aim of this research was to examine the effect of thermal treatments on the viability and infectivity of cryptosporidium parvum oocysts attached to a beef surface.200515715864
sporadic cryptosporidiosis decline after membrane filtration of public water supplies, england, 1996-2002.the incidence of sporadic cryptosporidiosis among 106,000 residents of 2 local government districts in northwest england before and after installation of membrane filtration of public water supplies was compared to that of 59,700 residents whose public water supplies remained unchanged. a national outbreak of foot and mouth disease in livestock during 2001 was associated with a decline in sporadic human cryptosporidiosis in all regions of the united kingdom. in a poisson regression model, membra ...200515752443
effect of halofuginone lactate on the occurrence of cryptosporidium parvum and growth of neonatal dairy calves.thirty-one holstein bull calves were purchased at birth from 3 dairy farms in eastern ontario. each calf was assigned at random to oral treatment with either 5 mg of halofuginone lactate in 10.0 ml of aqueous carrier solution (halocur, base comprised 10 mg of benzoic acid, 100 mg of lactic acid, and 0.3 mg of tartrazine) or 10 ml of placebo (halocur base minus the active ingredient, halofuginone lactate) administered 15 to 30 min after morning milk feeding for the first 7 d of life. intakes of m ...200515829673
incidence of cryptosporidium parvum in the dairy cattle population in a new york city watershed.a longitudinal study of 2-year duration was conducted to determine the risk, as measured by incidence rate, of cryptosporidium parvum infection among dairy cattle in the catskill/delaware watershed of new york city (nyc), and the factors that predispose animals to the likelihood of infection. a proportional sampling scheme with follow up at quarterly farm visits was employed for heifers and cows. additionally, all calves born on the 39 study farms were sampled once during the first four weeks of ...200515955631
prevalence and characterisation of cryptosporidium species in cattle faeces and on beef carcases at slaughter.cattle are known reservoirs and asymptomatic excretors of cryptosporidium, a protozoan parasite that causes severe and protracted diarrhoea in people. the incidence of cryptosporidium was investigated in 288 matched samples taken from beef carcases of 1 g samples of faeces retrieved immediately after de-legging, 25 cm2 samples of beef excised from the rump of uneviscerated carcases, and 25 cm2 samples of beef excised from the brisket area of eviscerated carcases. cryptosporidium species were det ...200515736696
prevalence of giardia and cryptosporidium in beef cows in southern ontario and in beef calves in southern british columbia.in 1998 and 1999, fecal samples were collected from 669 beef cows on 39 farms located within 10 counties of ontario. overall prevalences of giardia, cryptosporidium muris, and cryptosporidium parvum in cows were 8.7%, 10.6%, and 18.4%, respectively. of the 39 farms sampled, giardia was detected on 64%, cr. muris on 72%, and cr. parvum on 90%. cryptosporidium parvum was detected in 28% of the cows in 1998 and in 5.2% in 1999. differences between the 2 y were attributed to sampling during calving ...200515759828
risk of infection with cryptosporidium parvum and cryptosporidium hominis in dairy cattle in the new york city watershed.to determine the risk posed by cryptosporidium parvum and cryptosporidium hominis from dairy cattle in the new york city watershed (nycw).200515822584
declines of zoonotic agents in liquid livestock wastes stored in batches on-farm.to measure the decline rates of zoonotic agents introduced into liquid livestock wastes in on-farm storage tanks.200515960665
[cryptosporidiosis in newborn calves in ankara region: clinical, haematological findings and treatment with lasalocid-na].in the first part of the present study, a total of 109 faeces samples collected from calves suffering from diarrhoea were examined for cryptosporidium parvum oocytes and 39 (35.8%) of them were found to be positive. on the basis of oocyte counts, 14 (36%) samples were assessed as mildly infected and 25 (64%) samples as heavily infected. the occurrence of the disease was more common in winter (56.4%) than during other seasons (autuma 0%, summer 15.4% spring 28.2%. in the present study, the ionoph ...200516028484
seasonal temperature fluctuations induces rapid inactivation of cryptosporidium parvum.this study measured the inactivation rate of bovine genotype a cryptosporidium parvum oocysts attributable to diurnal oscillations of ambient temperature and solar radiation typical of california rangelands and dairies from spring through autumn. we first measured the relationship between air temperature and the internal temperature of bovine feces exposed to sunlight on commercial operations throughout california. once maximum air temperature exceeded the mid 20 degrees c, diurnal thermal regim ...200516047784
cryptosporidiumparvum oocysts in seawater clams (chameleagallina) in italy.bivalves filter large volumes of water and can concentrate organisms which are pathogenic for humans and animals. our aim was to evaluate the presence of cryptosporidium spp. in clams from the adriatic coast (abruzzo region) and genetically characterize the oocysts isolated from the clams. from march to july 2003, 960 specimens of clams (chamelea gallina) present in nature were collected at 500 m from the tordino, tronto, vibrata and vomano river mouths on the adriatic sea. the haemolymph and ti ...200515907570
cryptosporidium infection in livestock and first identification of cryptosporidium parvum genotype in cattle feces in taiwan.fecal survey by modified ziehl-neelsen (mzn) method and immunofluorescence assay (ifa) of cryptosporidium infection in cattle and goats in taiwan showed a prevalence of 37.6% (173/460) and 35.8% (44/123), respectively. in addition to the calves, adult cattle were also found to be shedding cryptosporidium oocyst. no significant difference was observed between diarrheic and non-diarrheic cattle feces with regard to the presence of cryptosporidium oocyst. two groups of oocysts with different diamet ...200515997405
multiattribute evaluation of two simple tests for the detection of cryptosporidium parvum in calf faeces.there is a need for simple and inexpensive diagnostic and screening tests for the detection of cryptosporidium parvum infection in calves. a sucrose wet mount test and a lateral immunochromatography test were evaluated for epidemiological sensitivity and specificity, cost per test, simplicity, test time and ease of batching. polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) of the cryptosporidium oocyst wall protein (cowp) gene locus, with gel electrophoresis, was use ...200516115735
molecular characterization of cryptosporidium species and genotypes in chile.knowledge of species and genotypes on cryptosporidium involved in human transmission is fundamental in studying the epidemiology of cryptosporidiosis. this is the first study in molecular epidemiology of cryptosporidiosis that has been made in chile. cryptosporidium parvum species and genotypes involved in human and bovine cryptosporidiosis were determined by pcr-rflp. low prevalence of cryptosporidium was found in humans and cattle. of the 127 cattle studied, only in one was c. parvum detected ...200515952040
prevalence of cryptosporidium parvum infection in southwestern ontario and its association with diarrhea in neonatal dairy calves.cryptosporidium parvum infection was detected in 203 (40.6%) of 500 ontario dairy calves aged 7 to 21 d, on a convenience sample of 51 farms with a history of calf diarrhea. within-farm prevalence ranged from 0% to 70%, and both shedding and intensity of shedding were significantly associated with diarrhea. this parasite appears to be common in ontario dairy calves and important as a cause of dairy calf scours in the province.200515943123
expression of p23 of cryptosporidium parvum in toxoplasma gondii and evaluation of its protective effects.in this study, p23 of cryptosporidium parvum sporozoites, an immunodominant surface protein, was stably expressed in toxoplasma gondii (tg/p23) and its protective effects were evaluated in a mouse model. the molecular weight and antigenic property of p23 expressed by tg/p23 were similar to those of the native p23. mice immunized with lysed tg/p23 tachyzoites produced specific neutralizing antibodies against c. parvum. these findings indicate that the t. gondii vector may provide a new tool for t ...200515986633
endoparasites in calves of beef cattle herds: management systems dependent and genetic influences.prevalences and intensities of excretion of faecal stages of giardia duodenalis, cryptosporidium parvum, eimeria spp., strongyloides papillosus and strongyles were determined in a german upland area in german angus (ga) and german simmental (gs) suckler of beef cattle herds covering two winter housing periods and the grazing season between them. influences of the housing systems applied (maintenance on deep litter with (dl+) and without run-out (dl--), on slatted floor (sf) or by winter run-out ...200515979802
the zoonotic transmission of giardia and cryptosporidium.the molecular characterisation of giardia and cryptosporidium has given rise to a more epidemiological meaningful and robust taxonomy. importantly, molecular tools are now available for 'typing' isolates of the parasites directly from clinical and environmental samples. as a consequence, information on zoonotic potential has been obtained although the frequency of zoonotic transmission is still poorly understood. analysis of outbreaks and case-control studies, especially when coupled with genoty ...200516159658
prevalence of species and genotypes of cryptosporidium found in 1-2-year-old dairy cattle in the eastern united states.the prevalence of cryptosporidium species in 1-2-year-old heifers was determined for 571 animals on 14 dairy farms in seven states on the east coast of the united states. a fecal specimen collected directly from each heifer was processed to concentrate oocysts that were then examined by polymerase chain reaction (pcr). for every pcr-positive specimen the 18s rrna gene of cryptosporidium was sequenced. cryptosporidium was identified by pcr from heifers on 13 of 14 farms. on all except four farms ...200616159697
development of a rapid method for simultaneous recovery of diverse microbes in drinking water by ultrafiltration with sodium polyphosphate and surfactants.the ability to simultaneously concentrate diverse microbes is an important consideration for sample collection methods that are used for emergency response and environmental monitoring when drinking water may be contaminated with an array of unknown microbes. this study focused on developing a concentration method using ultrafilters and different combinations of a chemical dispersant (sodium polyphosphate [napp]) and surfactants. tap water samples were seeded with bacteriophage ms2, escherichia ...200516269722
[protozoan infection causes diarrhea in calves].the role of protozoan parasites in the etiology of diarrhea in calves is highlighted with emphasis on correct diagnosis. in neonatal calves, cryptosporidium parvum is isolated in more than 44% of the faeces of diarrhetic calves. in calves older than one month, both eimeria bovis and e. zuernii, and giardia duodenalis are associated with diarrhea and poor growth. clinical diagnosis has to be confirmed by examination of host faecal material. both for c. parvum and g. duodenalis immunological assay ...200516363207
efficacy of nitazoxanide and paromomycin in biliary tract cryptosporidiosis in an immunosuppressed gerbil model.to evaluate the efficacy of nitazoxanide and paromomycin in biliary tract cryptosporidiosis in an immunosuppressed mongolian gerbil (meriones unguiculatus) model.200616361328
effect of bovine manure on cryptosporidium parvum oocyst attachment to soil.the objective of this work was to assess the effect of dilute bovine manure (1.0% and 0.1%) versus that of no manure on attachment and subsequent detachment of cryptosporidium parvum oocysts to soil. manure enhanced the attachment of oocysts to soil particles; the maximum attachment was observed with 0.1% manure. oocyst attachment was partially reversible; maximum detachment was observed with dilute manure. these results indicate that oocyst attachment to soil is substantially affected by bovine ...200516204565
patterns of cryptosporidium oocyst shedding by eastern grey kangaroos inhabiting an australian watershed.the occurrence of cryptosporidium oocysts in feces from a population of wild eastern grey kangaroos inhabiting a protected watershed in sydney, australia, was investigated. over a 2-year period, cryptosporidium oocysts were detected in 239 of the 3,557 (6.7%) eastern grey kangaroo fecal samples tested by using a combined immunomagnetic separation and flow cytometric technique. the prevalence of cryptosporidium in this host population was estimated to range from 0.32% to 28.5%, with peaks occurri ...200516204534
the occurrence of cryptosporidium parvum, campylobacter and salmonella in newborn dairy calves in the manawatu region of new zealand.to determine the occurrence of cryptosporidium parvum oocysts, campylobacter spp and salmonella spp in faecal samples taken from newborn dairy calves on 24 dairy farms in the manawatu region of new zealand.200516220123
recombinant bovine interleukin-12 stimulates a gut immune response but does not provide resistance to cryptosporidium parvum infection in neonatal calves.this study was undertaken to determine if administration of recombinant bovine interleukin-12 (rboil-12) could stimulate a cellular immune response that protected calves from an oral challenge inoculation with cryptosporidium parvum oocysts. in a first experiment, rboil-12 intraperitoneally administered as a single dose 1 day before challenge inoculation, did not alter the course of infection. the percentage of immune competent cells and levels of cytokine gene expression in the ileo-cecal mucos ...200616386849
interaction of cryptosporidium hominis and cryptosporidium parvum with primary human and bovine intestinal cells.cryptosporidiosis in humans is caused by the zoonotic pathogen cryptosporidium parvum and the anthroponotic pathogen cryptosporidium hominis. to what extent the recently recognized c. hominis species differs from c. parvum is unknown. in this study we compared the mechanisms of c. parvum and c. hominis invasion using a primary cell model of infection. cultured primary bovine and human epithelial intestinal cells were infected with c. parvum or c. hominis. the effects of the carbohydrate lectin g ...200616368962
environmental load of cryptosporidium parvum oocysts from cattle manure in feedlots from the central and western united states.the first step in assessing the risk of water contamination by cryptosporidium parvum oocysts from feedlot cattle (bos taurus) production systems is to quantify the number of c. parvum oocysts present in the fecal material deposited by feedlot cattle. our primary objective for this project was to estimate the daily environmental load of c. parvum oocysts in fecal material deposited by feedlot cattle from across the central and western usa. our secondary goal was to genotype isolates of c. parvum ...200616391291
cryptosporidium parvum bovine genotype oocysts in the respiratory samples of an aids patient: efficacy of treatment with a combination of azithromycin and paromomycin.cryptosporidium has been recognized as an emerging zoonotic agent of intestinal cryptosporidiosis leading to diarrhea, malabsorption syndrome, and weight loss in aids patients. in the present case, oocysts of zoonotic cryptosporidium parvum were detected in the sputum and stool samples of an aids patient with a 3-month history of intestinal cryptosporidiosis. the oocysts were detected by modified ziehl-neelsen staining; confirmation was achieved by nested polymerase chain reaction (pcr), targeti ...200616416289
efficacy of natural grassland buffers for removal of cryptosporidium parvum in rangeland runoff.our goal for this project was to estimate the retention efficiency of natural grassland buffers for cryptosporidium parvum. three sets of 16 plots (2.0 by 3.0 m) were established at 5, 20, and 35% slopes. within each set of 16 plots, residual dry vegetation matter treatments of 225, 560, and 900 kg/ha were implemented, along with a noncut control averaging 4,500 kg/ ha. buffer width treatments were implemented by placing cattle fecal material containing known loads of c. parvum 0.1, 1.1, or 2.1 ...200616416916
response of t lymphocytes from previously infected calves to recombinant cryptosporidium parvum p23 vaccine antigen.we had previously demonstrated that a type-1-like immune response involving interferon-gamma expression in lamina propria lymphocytes accompanied by igg2 subclass fecal antibodies to cryptosporidium parvum p23 emerged in gut mucosa of calves recovering from cryptosporidiosis. because a recombinant p23 had been shown to protect calves from cryptosporidiosis when administered as a vaccine antigen to late gestation cattle, this study was undertaken to determine if the same vaccine antigen could ind ...200516419781
longitudinal analysis of cryptosporidium species-specific immunoglobulin g antibody responses in peruvian children.cryptosporidium species are ubiquitous in the environment and are frequently detected in the stools of children who live where sanitation conditions are poor. to better characterize the immune response to these parasites, we monitored immunoglobulin g (igg) antibody levels in a cohort of children from lima, peru. two new enzyme-linked immunosorbent assays based on the c. parvum (bovine, subtype iia) iowa strain 17-kda and 27-kda antigens were used to measure igg antibody levels in longitudinal s ...200616426009
persistent infection in a dairy herd with an unusual genotype of bovine cryptosporidium parvum.on two occasions, we identified cryptosporidium parvum with an unusual banding pattern after restriction enzyme digestion of cryptosporidium oocyst wall protein pcr fragments. the samples originated from a single farm with calf diarrhoea. the cryptosporidium oocyst wall protein pcr fragment sequence revealed a point mutation in one of the recognition sites for rsai. our subgenotyping showed that samples from both samplings shared the same ms1 and gp15 alleles. analysis of the tp14 microsatellite ...200616451181
changes of physical and biochemical properties of cryptosporidium oocysts with various storage conditions.physical and biochemical properties of cryptosporidium parvum oocyst were examined after storage under various conditions. oocyst-positive-fecal samples recovered from calves were either stored in a 2.0% potassium dichromate solution (cr) or deionized water (w), or kept as a fecal pellet (p), and stored at 4 or 18 degrees c for a maximum of 100 days. when stored in cr at 4 degrees c, the morphology of oocysts and their ability to withstand ultrasonics was not affected by the storing media or the ...200616458949
identification of isoflavone derivatives as effective anticryptosporidial agents in vitro and in vivo.we report the preparation and antiparasitic activity in vitro and in vivo of a series of isoflavone derivatives related to genistein. these analogues retain the 5,7-dihydroxyisoflavone core of genistein: direct genistein analogues (2-h isoflavones), 2-carboethoxy isoflavones, and the precursor deoxybenzoins were all evaluated. excellent in vitro activity against cryptosporidium parvum was observed for both classes of isoflavones in cell cultures, and the lead compound 19, rm6427, shows high in v ...200616480281
cryptosporidium oocysts in mussels (mytilus edulis) from normandy (france).cultured mussels (mytilus edulis) were collected seasonally during one year from three sites on the northwestern coastal area of normandy (france). flesh, gills and innerwater were examined for cryptosporidium oocyst detection using immunomagnetic separation and immunofluorescence assay. oocysts were present in all samples for all sites and seasons and flesh was the most contaminated part. oocyst rates were apparently related with seasonal rain precipitation variations. molecular analysis reveal ...200616488039
age-related and housing-dependence of cryptosporidium infection of calves from dairy and beef herds in south bohemia, czech republic.data of the prevalence, age-related and housing-dependence of naturally acquired cryptosporidiosis on 11 dairy and 11 beef farms in south bohemia (czech republic) were collected. the farms were visited over four consecutive years (from 2002 to 2005). the prevalence of cryptosporidium in pre-weaned (animals until second month of age) and post-weaned (animals from the third month of age) calves was determined. a total of 7001 faecal samples were collected, concentrated by sheather's floatation met ...200616488542
survival of cryptosporidium parvum oocysts in calf housing facilities in the new york city watersheds.pathogen contamination of the public drinking water supply in the new york city watersheds is a serious concern. new york city's watershed agriculture program is working with dairy farms in the watersheds to implement management practices that will reduce the risk of pathogens contaminating the water supply. solar calf housing (sch) was suggested as a best management practice (bmp) to control cryptosporidium parvum, a common protozoan parasite that causes disease in humans. this bmp targets youn ...200616510713
quantitative risk assessment of cryptosporidium species infection in dairy calves.cryptosporidium parvum is a zoonotic protozoan that infects many different mammals including cattle and humans. cryptosporidiosis has become a concern for dairy producers because of the direct losses due to calves not performing well and the potential for environmental contamination with c. parvum. identifying modifiable control points in the dynamics of infection in dairy herds will help identify management strategies that mitigate its risk. the quantitative risk assessment approach provides es ...200516230699
inhibitory activities of epidermal growth factor receptor tyrosine kinase-targeted dihydroxyisoflavone and trihydroxydeoxybenzoin derivatives on sarcocystis neurona, neospora caninum, and cryptosporidium parvum development.several gene sequences of parasitic protozoa belonging to protein kinase gene families and epidermal growth factor (egf)-like peptides, which act via binding to receptor tyrosine kinases of the egf receptor (egfr) family, appear to mediate host-protozoan interactions. as a clue to egfr protein tyrosine kinase (ptk) mediation and a novel approach for identifying anticoccidial agents, activities against sarcocystis neurona, neospora caninum, and cryptosporidium parvum grown in bm and hct-8 cell cu ...200516251305
prevalence and genotyping of cryptosporidium in three cattle husbandry systems in zambia.to estimate the prevalence of cryptosporidium spp. in three different husbandry systems in zambia, faecal samples were collected from calves up to the age of 3 months. faecal consistency was scored for correlation with infection. additionally, 45 positive samples were selected for genotyping by amplification of the 70-kda heat shock protein (hsp-70) and the 18s rrna gene. a total of 37 dairy, 25 beef and 92 traditional husbandry farms were visited: 250 samples were collected on dairy farms, 238 ...200616546321
the relationship of soil province to molecular characterization and phylogenetic analysis of cryptosporidium parvum isolated from calves in georgia.although cryptosporidium spp. are found throughout the world and in multiple environmental conditions, few data are available that explore the possibility of an association between specific environmental parameters and the species or strain of cryptosporidium. this study examines the potential association between a particular cryptosporidium species/strain found in calves and soil provinces in georgia, usa. necropsy cases spanning the years 1996-2002 were tested. no significant differences (p=0. ...200616516506
genotype analysis of cryptosporidium spp. prevalent in a rural village in hwasun-gun, republic of korea.two species of cryptosporidium are known to infect man; c. hominis which shows anthroponotic transmission between humans, and c. parvum which shows zoonotic transmission between animals or between animals and man. in this study, we focused on identifying genotypes of cryptosporidium prevalent among inhabitants and domestic animals (cattle and goats), to elucidate transmittal routes in a known endemic area in hwasun-gun, jeollanam-do, republic of korea. the existence of cryptosporidium oocysts wa ...200616514279
genotype and subtype analyses of cryptosporidium isolates from dairy calves and humans in ontario.to assess the importance of dairy cattle as a source of human cryptosporidium infections in ontario, canada, 44 cryptosporidium isolates from neonatal dairy calves and 11 from sporadic human cases of cryptosporidiosis in the province were genotyped by pcr-rflp analyses of the cryptosporidium oocyst wall protein (cowp) and 18s rrna genes. isolates were also subtyped by sequence analysis of the 60-kda glycoprotein (gp60) gene. all bovine isolates successfully subtyped belonged to cryptosporidium p ...200616565813
cryptosporidium parvum infections in bergen, norway, during an extensive outbreak of waterborne giardiasis in autumn and winter 2004.during a large waterborne giardiasis outbreak in norway, many diarrheic patients were found to have cryptosporidium infections. gene sequencing identified these infections as cryptosporidium parvum infections, although they were not identical. whether these infections were due to a simultaneous outbreak of waterborne cryptosporidiosis or reflected background levels not normally detected is discussed.200616517675
subgenotype analysis of cryptosporidium parvum isolates from humans and animals in japan using the 60-kda glycoprotein gene sequences.cryptosporidium parvum is a well-known intestinal parasite which is associated with severe acute diarrhea in humans and animals. this parasite is composed of morphologically identical but genetically different multiple genotypes. in humans, cryptosporidiosis is mainly caused by two c. parvum genotypes, human genotype (previously known as genotype 1 and recently proposed as new species c. hominis) and cattle genotype (previously known as genotype 2). however, recent molecular studies indicate the ...200616565816
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