| [research advances in the pathogenicity associated proteins of cryptosporidium parvum]. | | 2004 | 15587165 |
| myxobolus sp: a possible new opportunistic parasite in immunocompromized patients in ismailia. | during a study on intestinal parasitic infections in immunocompromized patients complaining of diarrhoea, a parasite belonging to the phylum myxozoa described from human samples was identified in three stool samples out of eleven. on staining with modified ziehl-neelsen stain the spores were identified. they were pyriform in shape with an average size 14.0 micro x 10.0 micro. every spore has thick wall and one suture in the anterior third followed by two polar capsules. each polar capsule has ab ... | 2004 | 15587318 |
| molecular identification of coproantigens of cryptosporidium parvum compared to conventional staining techniques. | to compare the immunologic techniques to the conventional staining methods (mainly modified ziehl neelsen = mzn), 93 children (65 immunocompromised and 28 immunocompetent) potentially at risk of cryptosporidium parvum were studied. using mzn, a prevalence of 10.7% in diarrhoeic children was found. elisa coproantigen and detection of 23 kda band of immunoblotting by serum igg were sensitive and specific. they gave 85.7% sensitivity, 100% specificity, 100% diagnostic accuracy, 100% positive predic ... | 2004 | 15587321 |
| 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 ... | 2004 | 15606351 |
| management of gastrointestinal disorders in children with hiv infection. | a double scenario characterizes the epidemiology of hiv infection in children. in countries where highly active antiretroviral therapy (haart) is available, the pattern of hiv infection is evolving into that of a chronic disease, for which control strictly depends on patients' adherence to treatment. in developing countries with no or limited access to haart, aids is rapidly expanding and is loaded with a high fatality ratio, due to the combined effects of malnutrition and opportunistic infectio ... | 2004 | 15612836 |
| prevalence of intestinal parasitic pathogens among hiv-positive individuals in iran. | parasites are important enteric pathogens among patients with human immunodeficiency virus (hiv) infection. there have been very few reports on the prevalence of intestinal parasites among such patients in iran. to determine the prevalence of intestinal parasites among hiv-positive individuals, we collected single stool samples and analyzed them for detection of various intestinal parasites from 206 hiv-positive individuals with different immune status visited in different medical centers in ira ... | 2004 | 15623953 |
| 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. | 2004 | 15626945 |
| chronic diarrhea. | | 2005 | 15629902 |
| use of artificial neural networks to accurately identify cryptosporidium oocyst and giardia cyst images. | cryptosporidium parvum and giardia lamblia are protozoa capable of causing gastrointestinal diseases. currently, these organisms are identified using immunofluorescent antibody (ifa)-based microscopy, and identification requires trained individuals for final confirmation. since artificial neural networks (ann) can provide an automated means of identification, thereby reducing human errors related to misidentification, ann were developed to identify cryptosporidium oocyst and giardia cyst images. ... | 2005 | 15640173 |
| role of surface proteins in the deposition kinetics of cryptosporidium parvum oocysts. | a radial stagnation point flow system was used to investigate the influence of cryptosporidium parvum surface properties on oocyst deposition kinetics onto solid surfaces. to determine the role of oocyst surface proteins in adhesion, the deposition kinetics of viable oocysts were compared with the deposition kinetics of oocysts treated (inactivated) with either heat or formalin. results showed a significantly higher deposition rate with formalin and heat-treated oocysts compared to viable oocyst ... | 2005 | 15641844 |
| the detection of cryptosporidium parvum and escherichia coli o157 in uk bivalve shellfish. | optimised immunomagnetic separation methods to detect cryptosporidium parvum and escherichia coli o157 in uk shellfish are described. whole tissue homogenates gave the best recoveries for c. parvum oocysts compared with gill or haemolymph extracts. the sensitivity of recovery from spiked samples was comparable to that achieved when processing water and varied from 12-34% in mussels, 48-69.5% in oysters and 30-65% in scallops. maximum recovery of e. coli o157 was achieved by enriching in buffered ... | 2005 | 15649541 |
| land application of treated sewage sludge: quantifying pathogen risks from consumption of crops. | to predict the number of humans in the uk infected through consumption of root crops grown on agricultural land to which treated sewage sludge has been applied in accordance with the current regulations and guidance (safe sludge matrix). | 2005 | 15659193 |
| the unusual mitochondrial compartment of cryptosporidium parvum. | recent studies, including the cryptosporidium parvum genome project, have provided evidence for a mitochondrial-derived compartment in this parasite. this organelle appears to lack a genome, and thus must be entirely dependent on nuclear-encoded proteins. here, we review the evidence for such an organelle in c. parvum and its probable function. there is no adequate treatment for infection by this parasite and so the elucidation of the role of this organelle and the effective targeting of its fun ... | 2005 | 15664529 |
| the response of cryptosporidium parvum to uv light. | ultraviolet (uv) light is being considered as a disinfectant by the water industry because it appears to be very effective for controlling potential waterborne pathogens, including cryptosporidium parvum. however, many organisms have mechanisms such as nucleotide excision repair and photolyase enzymes for repairing uv-induced dna damage and regaining preirradiation levels of infectivity or population density. genes encoding uv repair proteins exist in c. parvum, so the parasite should be able to ... | 2005 | 15664531 |
| adhesion kinetics of viable cryptosporidium parvum oocysts to quartz surfaces. | the transport and deposition (adhesion) kinetics of viable cryptosporidium parvum oocysts onto ultrapure quartz surfaces in a radial stagnation point flow system were investigated. utilizing an optical microscope and an image-capturing device enabled real time observation of oocyst deposition behavior onto the quartz surface in solutions containing either monovalent (kcl) or divalent (cacl2) salts. results showed a significantly lower oocyst deposition rate in the presence of a monovalent salt c ... | 2004 | 15669347 |
| identification of cryptosporidium parvum genotype 2 in domestic horses. | | 2005 | 15675524 |
| [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 ... | 2004 | 15683036 |
| how clean must our drinking water be: the importance of protective immunity. | cryptosporidium parvum is an important cause of epidemic diarrhea. few studies have assessed whether serological evidence of prior infection in adults is related to a reduced occurrence of enteric illness. | 2005 | 15688300 |
| comparison of cryptosporidium parvum development in various cell lines for screening in vitro drug testing. | this study describes the development of cryptosporidium parvum in mdck, ma-104, hep-2 and vero cell lines. differences in susceptibility, infectivity, and the methodology of excystation were determined. various solutions were considered to determine the factors which enhanced the excystation (eg with and without sodium hypochlorite, trypsin or sodium taurocholate). it was shown that the sporozoites could be excysted in media either with or without trypsin and sodium taurocholate, but the number ... | 2004 | 15689063 |
| 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 ... | 2005 | 15691918 |
| detection and discrimination of cryptosporidium parvum and c. hominis in water samples by immunomagnetic separation-pcr. | cryptosporidium parvum and c. hominis have been the cause of large and serious outbreaks of waterborne cryptosporidiosis. a specific and sensitive recovery-detection method is required for control of this pathogen in drinking water. in the present study, nested pcr-restriction fragment length polymorphism (rflp), which targets the divergent cpgp40/15 gene, was developed. this nested pcr detected only the gene derived from c. parvum and c. hominis strains, and rflp was able to discriminate betwee ... | 2005 | 15691946 |
| association of cryptosporidium parvum with suspended particles: impact on oocyst sedimentation. | the association of cryptosporidium parvum oocysts with suspended particles can alter the oocysts' effective physical properties and influence their transport in aquatic systems. to assess this behavior, c. parvum oocysts were mixed with various suspended sediments under a variety of water chemical conditions, and the resulting settling of the oocysts was observed. direct microscopic observations showed that oocysts attached to suspended sediments. settling column and batch experiments demonstrat ... | 2005 | 15691968 |
| parasitic infections of the gastrointestinal tract. | intestinal parasites continue to be a significant health problem in both developed and developing countries. in developed countries, protozoans are more commonly the cause of gastrointestinal infections than are helminths. some protozoan parasites have stages in which, in addition to being resistant to chemicals used for water treatment, they are small enough to pass through commonly used filtration processes. the relatively large size of helminth eggs increases the likelihood of their removal d ... | 2003 | 15699890 |
| emerging food-borne zoonoses. | diarrhoeal diseases, almost all of which are caused by food-borne or waterborne microbial pathogens, are leading causes of illness and death in less developed countries, killing an estimated 1.9 million people annually at the global level. even in developed countries, it is estimated that up to one third of the population are affected by microbiological food-borne diseases each year. the majority of the pathogens causing this significant disease burden are now considered to be zoonotic. the occu ... | 2004 | 15702717 |
| 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. | 2005 | 15715864 |
| the domain architecture of large guanine nucleotide exchange factors for the small gtp-binding protein arf. | small g proteins, which are essential regulators of multiple cellular functions, are activated by guanine nucleotide exchange factors (gefs) that stimulate the exchange of the tightly bound gdp nucleotide by gtp. the catalytic domain responsible for nucleotide exchange is in general associated with non-catalytic domains that define the spatio-temporal conditions of activation. in the case of small g proteins of the arf subfamily, which are major regulators of membrane trafficking, gefs form a he ... | 2005 | 15717927 |
| do iodine water purification tablets provide an effective barrier against cryptosporidium parvum? | u.s. army iodine water purification tablets were tested to determine their efficacy against cryptosporidium parvum, a protozoan resistant to chemical disinfection. purified oocysts in phosphate-buffered water were treated with varying concentrations of iodine or with iodine tablets as per u.s. army protocol. neonatal mouse pups were then each inoculated with 10,000 treated oocysts, and 1 week later scored as infected or uninfected. using this methodology, iodine tablets were found to be inadequa ... | 2005 | 15724860 |
| cross-reactivities with cryptosporidium spp. by chicken monoclonal antibodies that recognize avian eimeria spp. | in a previous study, we have developed several chicken monoclonal antibodies (mabs) against eimeria acervulina (ea) in order to identify potential ligand molecules of eimeria. one of these mabs, 6d-12-g10, was found to recognize a conoid antigen of ea sporozoites and significantly inhibited the sporozoite invasions of host t lymphocytes in vitro. furthermore, some of these chicken mabs showed cross-reactivities with several different avian eimeria spp. and the mab 6d-12-g10 also demonstrated cro ... | 2004 | 15725532 |
| cryptosporidium excystation and invasion: getting to the guts of the matter. | cryptosporidium parvum excystation and host cell invasion have been characterized in some detail ultrastructurally. however, until recently, the biochemical and molecular basis of host-parasite interactions and parasite- and host-specific molecules involved in excystation, motility and host cell invasion have been poorly understood. this article describes our understanding of cryptosporidium excystation and the events leading to host cell invasion, and draws from information available about thes ... | 2005 | 15734661 |
| 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 ... | 2005 | 15736696 |
| 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 ... | 2005 | 15746310 |
| quantitative-pcr assessment of cryptosporidium parvum cell culture infection. | a quantitative taqman pcr method was developed for assessing the cryptosporidium parvum infection of in vitro cultivated human ileocecal adenocarcinoma (hct-8) cell cultures. this method, termed cell culture quantitative sequence detection (cc-qsd), has numerous applications, several of which are presented. cc-qsd was used to investigate parasite infection in cell culture over time, the effects of oocyst treatment on infectivity and infectivity assessment of different c. parvum isolates. cc-qsd ... | 2005 | 15746352 |
| effect of batch-process solar disinfection on survival of cryptosporidium parvum oocysts in drinking water. | the results of batch-process solar disinfection (sodis) of cryptosporidium parvum oocysts in water are reported. oocyst suspensions were exposed to simulated sunlight (830 w m(-2)) at 40 degrees c. viability assays (4',6'-diamidino-2-phenylindole [dapi]/propidium iodide and excystation) and infectivity tests (swiss cd-1 suckling mice) were performed. sodis exposures of 6 and 12 h reduced oocyst infectivity from 100% to 7.5% (standard deviation = 2.3) and 0% (standard deviation = 0.0), respective ... | 2005 | 15746372 |
| 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 ... | 2005 | 15750054 |
| a new apicomplexa-specific protein kinase family: multiple members in plasmodium falciparum, all with an export signature. | malaria caused by protozoan parasites of the genus plasmodium spp. is a major health burden in tropical countries. the development of new control tools, including vaccines and drugs, is urgently needed. the availability of genome sequences from several malaria parasite species provides a basis on which to identify new potential intervention targets. database mining for orthologs to the plasmodium falciparum trophozoite protein r45, a vaccine candidate, led us identify a new gene family. | 2005 | 15752424 |
| 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 ... | 2005 | 15752443 |
| straining, attachment, and detachment of cryptosporidium oocysts in saturated porous media. | accurate knowledge of the transport and deposition behavior for pathogenic cryptosporidium parvum oocysts is needed to assess contamination and protect water resources. experimental and modeling studies were undertaken to examine the roles of attachment, detachment, and straining on oocyst transport and retention. saturated column studies were conducted using ottawa aquifer sands (u.s. silica, ottawa, il) with median grain sizes of 710, 360, and 150 microm. decreasing the median sand size tended ... | 2005 | 15758099 |
| 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 ... | 2005 | 15759828 |
| capture of water-borne colloids in granular beds using external electric fields: improving removal of cryptosporidium parvum. | suboptimal coagulation in water treatment plants often results in reduced removal efficiency of cryptosporidium parvum oocysts by several orders of magnitude (j. awwa 94(6) (2002) 97, j. awwa 93(12) (2001) 64). the effect of external electric field on removal of c. parvum oocysts in packed granular beds was studied experimentally. a cylindrical configuration of electrodes, with granular media in the annular space was used. a negative dc potential was applied to the central electrode. no coagulan ... | 2005 | 15766959 |
| 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 ... | 2005 | 15777916 |
| parasitic infections in hiv-infected patients who visited seoul national university hospital during the period 1995-2003. | the prevalence of parasitic infections was investigated in human immunodeficiency virus (hiv)-infected patients (n = 105) who visited seoul national university hospital, seoul, korea, during the period from 1995 to 2003. fecal samples were collected from 67 patients for intestinal parasite examinations, and sputum or bronchoalveolar lavage samples from 60 patients for examination of pneumocystis carinii. both samples were obtained from 22 patients. thirty-three (31.4%) of the 105 were found to h ... | 2005 | 15793352 |
| immuno-capture of cryptosporidium parvum using micro-well array. | a glass slide and micro-well array chip on which anti-cryptosporidium parvum antibody was immobilized were used for the rapid capture and detection of c. parvum. biotinylated anti-c. parvum antibodies were spotted onto the streptavidin-coated glass slides. c. parvum oocysts were captured specifically on the spot when more than 73 ng of anti-c. parvum antibody was applied onto the glass slide. however, c. parvum oocysts captured on the glass slide were detached by repeating washing steps. to impr ... | 2005 | 15797326 |
| mucosal cytokine and antigen-specific responses to cryptosporidium parvum in il-12p40 ko mice. | studies of cellular immune responses to cryptosporidium parvum have been limited in part by lack of suitable animal models. il-12p40(-/-)mice are susceptible to initial infection with c. parvum but recover within 2 weeks, rendering the animals resistant to reinfection. because the host responses that determine duration and severity of primary infection are not yet understood, we studied the cellular immune response to primary infection with c. parvum in il-12p40(-/-)mice and also explored possib ... | 2005 | 15813719 |
| electron tomographic and ultrastructural analysis of the cryptosporidium parvum relict mitochondrion, its associated membranes, and organelles. | sporozoites of the apicomplexan cryptosporidium parvum possess a small, membranous organelle sandwiched between the nucleus and crystalloid body. based upon immunolabelling data, this organelle was identified as a relict mitochondrion. transmission electron microscopy and tomographic reconstruction reveal the complex arrangement of membranes in the vicinity of this organelle, as well as its internal organization. the mitochondrion is enveloped by multiple segments of rough endoplasmic reticulum ... | 2005 | 15817118 |
| immunization protocols against cryptosporidium parvum in ovines: protection in suckling lambs. | ovine colostrum and milk from immunized ewes were tested for their ability to prevent cryptosporidiosis in the lambs experimentally infected with 10(6) oocysts of cryptosporidium parvum at 36-48 h of age (day 0 post-infection). all lambs became infected and developed clinical cryptosporidiosis. however, lambs fed by immunized dams have shown shedding involved, significantly, fewer oocysts and lasted for a shorter period than in control lambs. in addition, diarrhoea was less severe. the best resu ... | 2005 | 15817197 |
| 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). | 2005 | 15822584 |
| frequency and characteristics of selected enteropathogens in fecal and rectal specimens from childhood diarrhea in trinidad, 1998-2000. | to determine the prevalence and characteristics of selected enteric pathogens in diarrheic children in six counties of the island of trinidad. | 2005 | 15826396 |
| 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 ... | 2005 | 15829673 |
| parasitic zoonoses in papua new guinea. | relatively few species of zoonotic parasites have been recorded in humans in papua new guinea. a greater number of potentially zoonotic species, mostly nematodes, occur in animals but are yet to be reported from humans. protozoa is the best represented group of those infecting man, with giardia duodenalis, cryptosporidium parvum, cyclospora cayetanesis, toxoplasma gondii, sarcocystis spp., entamoeba polecki, balantidium coli and, possibly, blastocystis hominis. the only zoonotic helminths infect ... | 2005 | 15831107 |
| diarrhea associated with cryptosporidium parvum among young children of the nile river delta in egypt. | over a 2-year period, the prevalence and clinical characteristics of cryptosporidium-associated diarrhea in the nile river delta of egypt was studied. a stool sample was obtained from children with diarrhea attending one of two study hospitals and of the 1275 children evaluated, 214 (17%) were found to be infected with cryptosporidium. younger age was a risk factor for developing cryptosporidium-associated diarrhea. children <12 months of age were 2.4 times more likely to be infected with crypto ... | 2005 | 15831665 |
| cryptosporidium infection in renal transplant patients. | cryptosporidium parvum, an intracellular protozoan parasite, is a significant cause of gastrointestinal disease worldwide. transmission can occur from an infected person, animal or fecally contaminated environment. the clinical manifestations of cryptosporidiosis are dependent on the immunologic state of the host. infection among immunocompetent hosts results in diarrhea that is typically self-limited. in immunocompromised hosts, however, the infection may be protracted and life-threatening with ... | 2005 | 15847259 |
| [diagnosis of coccidia and microspores in specimens of diarrheal feces from cuban hiv seropositive patients: first report of microspores in cuba]. | the numerous specimens of liquid diarrheas received at the clinical parasitology laboratory of "pedro kouri" institute of tropical medicine were studied searching for the presence of pathogenic agents of coccidium subclass and of the microspore family. the conditions to diagnose microsporidia were created on july 13, 2000, and the method was incorporated to the battery of diagnostic techniques used in the laboratory. a cut-off was made after 4 months to analyze the positivity found. a frequency ... | 2003 | 15849947 |
| [intestinal parasitosis in children admitted to the pediatric teaching hospital of cerro, havana city, cuba]. | a study on intestinal parasitism was conducted among 401 children admitted in the pediatric teaching hospital of cerro, from may to june, 1999. to this end, a representative, randomized and stratified sample by service was taken. 3 samples of feces per child were collected, preserved in formaldehyde, and processed by 3 parasitological methods. there was an intestinal parasitism prevalence of 15% at the hospital and there were no differences between the stratum of children admitted in gastroenter ... | 2003 | 15849948 |
| localized glucose and water influx facilitates cryptosporidium parvum cellular invasion by means of modulation of host-cell membrane protrusion. | dynamic membrane protrusions such as lamellipodia and filopodia are driven by actin polymerization and often hijacked by intracellular microbes to enter host cells. the overall rate of membrane protrusion depends on the actin polymerization rate and the increase of localized cell volume. although the signaling pathways involving actin polymerization are well characterized, the molecular mechanisms regulating local cell volume associated with membrane protrusion are unclear. cryptosporidium parvu ... | 2005 | 15851691 |
| asymptomatic cryptosporiosis in a periurban slum setting in kolkata, india--a pilot study. | we report the results of a prospective study conducted among asymptomatic children of slum dwellers in kolkata, eastern india, to assess the prevalence of cryptosporidium parvum during the period of october 2002 to july 2003. of the 609 fecal samples examined, c. parvum was detected in 14 (2.3%). the study indicated that poor sanitary conditions may be cofactors for the cryptosporidial disease burden among slum dwellers. the implications of asymptomatic infections have been discussed. | 2005 | 15858292 |
| clams (corbicula fluminea) as bioindicators of fecal contamination with cryptosporidium and giardia spp. in freshwater ecosystems in california. | this study evaluated clams as bioindicators of fecal protozoan contamination using three approaches: (i) clam tissue spiking experiments to compare several detection techniques; (ii) clam tank exposure experiments to evaluate clams that had filtered cryptosporidium oocysts from inoculated water under a range of simulated environmental conditions; (iii) sentinel clam outplanting to assess the distribution and magnitude of fecal contamination in three riverine systems in california. our spiking an ... | 2005 | 15862580 |
| efficacy of two peroxygen-based disinfectants for inactivation of cryptosporidium parvum oocysts. | two commercial peroxygen-based disinfectants containing hydrogen peroxide plus either peracetic acid (ox-virin) or silver nitrate (ox-agua) were tested for their ability to inactivate cryptosporidium parvum oocysts. oocysts were obtained from naturally infected goat kids and exposed to concentrations of 2, 5, and 10% ox-virin or 1, 3, and 5% ox-agua for 30, 60, and 120 min. in vitro excystation, vital dyes (4',6'-diamidino-2-phenylindole and propidium iodide), and infectivity in neonatal balb/c ... | 2005 | 15870337 |
| uv inactivation of cryptosporidium hominis as measured in cell culture. | the cryptosporidium spp. uv disinfection studies conducted to date have used cryptosporidium parvum oocysts. however, cryptosporidium hominis predominates in human cryptosporidiosis infections, so there is a critical need to assess the efficacy of uv disinfection of c. hominis. this study utilized cell culture-based methods to demonstrate that c. hominis oocysts displayed similar levels of infectivity and had the same sensitivity to uv light as c. parvum. therefore, the water industry can be con ... | 2005 | 15870378 |
| cryptosporidiosis in harare, zimbabwe. | to determine the prevalence of cryptosporidium parvum in diarrhoeal patients. | 2004 | 15881311 |
| mixed infection with three intestinal coccidian parasites in an aids patient. | | 2004 | 15884456 |
| detection of cryptosporidium parvum oocysts on fresh vegetables and 1 herbs using antibodies specific for a cryptosporidium parvum viral antigen. | the purpose of this study was to determine if the viral symbiont of cryptosporidium parvum (cpv) sporozoites could be used as a target for sensitive detection of the parasite in food samples. polyclonal sera specific to the recombinant viral capsid protein (rcpv40) was used in a dot blot hybridization assay to detect oocysts recovered from green onions and cilantro. small batches of chopped green onions and cilantro leaves were artificially contaminated with three different concentrations of ooc ... | 2005 | 15895749 |
| 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 ... | 2005 | 15907570 |
| extracellular like-gregarine stages of cryptosporidium parvum. | the present study confirms the existence of extracellular stages of cryptosporidiumparvum during in vitro culture on mdck, hct 8 and vero cells as well as alveolar macrophages, by optic, nomarski and transmission electron microscopy images. extracellular trophozoite/gamont, stages in syzygy, zygotes and spores with eight sporozoites were seen in the supernatant of the cultures. the first ultrastructural images of extracellular stages of c. parvum are shown in this study. the morphology of these ... | 2005 | 15907779 |
| significance of cryptosporidium parvum in horses. | | 2005 | 15908503 |
| [intestinal parasitosis during aids diarrhoea]. | the main goal of this work was to study the parasitic infections during aids diarrhoea. a longitudinal study was carried out from october 2000 to november 2001 in the hepato-gastro-enterology department of gabriel toure hospital and in the department of epidemiology and parasitic infections of faculty of medicine, pharmacy and odonto-stomatology of bamako (mali), concerning hiv positive patients suffering from diarrhoea. detecting microbes in stools has been done through direct microscopic exami ... | 2005 | 15915971 |
| cryptosporidium infection impairs growth and muscular protein synthesis in suckling rats. | this study aimed to explore the metabolic consequences of cryptosporidiosis in an acute experimental model both at the peak of infection and after parasite clearance. four-day-old suckling rats were infected with 10(6) oocysts of cryptosporidium parvum. at the peak of infection (day 8 pi), c. parvum resulted in a dramatic reduction both in nutrient intake (-50%) and body weight (16.3+/-5.2 vs 27.3+/-1.0 g, p<0.01) with a decrease in both lean body mass and adipose tissue. muscular fractional and ... | 2005 | 15924222 |
| a histological study of the transit of cryptosporidium parvum oocysts through clams (tapes decussatus). | a histological study was carried out to investigate the transit of cryptosporidium parvum oocysts through the clam tapes decussatus. spat of approximately 5-7 mm shell length were maintained in a tank of natural sea water contaminated with purified c. parvum oocysts. the experiment lasted 240 h and, every 24 h, five specimens were killed, placed in bouin's fixative, and processed routinely for histological examination. sections (3 mum) cut from the all body tissues were stained with modified gom ... | 2005 | 15925002 |
| characterisation of a cryptosporidium isolate from water buffalo (bubalus bubalis) by sequencing of a fragment of the cryptosporidium oocyst wall protein gene (cowp). | cryptosporidium oocysts were detected using a direct immunofluorescence antibody test in the faeces of an asymptomatic water buffalo (bubalus bubalis) heifer from a dairy farm close to santiago de compostela (nw spain). oocysts were morphologically indistinguishable from cryptosporidium parvum. using dna extracted from this sample and a pcr-rflp analysis of a 341 base pairs fragment of the cryptosporidium oocyst wall protein (cowp) gene, a previously undescribed fragment pattern was generated. t ... | 2005 | 15935559 |
| 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. | 2005 | 15943123 |
| 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 ... | 2005 | 15952040 |
| spatial distributions of cryptosporidium oocysts in porous media: evidence for dual mode deposition. | spatial distributions of cryptosporidium parvum oocysts in columns packed with uniform glass-bead collectors were measured over a broad range of physicochemical conditions. oocyst deposition behavior is shown to deviate from predictions based on classical colloid filtration theory (cft) in the presence of repulsive (unfavorable) colloidal interactions. specifically, cft tends to predict greater removal of oocysts (less transport) than that observed in controlled laboratory experiments. compariso ... | 2005 | 15952366 |
| development and test for long-term stability of a synthetic standard for a quantitative cryptosporidium parvum lightcycler pcr assay. | a recently described quantitative rapid cycle real time pcr (lightcycler) assay detects cryptosporidium parvum after in vitro excystation, which is a surrogate marker for the viability of the organisms. in the original assay the quantification standard is a dilution series of c. parvum oocysts with a microscopically determined excystation rate. the need to keep suspensions of viable oocysts in stock and to continuously monitor their excystation rate, however, renders the assay impracticable for ... | 2005 | 15952449 |
| serological responses to cryptosporidium antigens among women using riverbank-filtered water, conventionally filtered surface water and groundwater in hungary. | we compared serological responses to cryptosporidium parvum antigens using surplus sera from females undergoing routine screening for pregnancy from three counties in hungary where bank-filtered surface water, conventionally filtered and disinfected surface water, and groundwater from either a karst or confined aquifer are commonly used for drinking water. the primary purpose was to determine whether the prevalence and intensity of serological responses, indicators of prior cryptosporidium infec ... | 2005 | 15952455 |
| crystallization of three key glycolytic enzymes of the opportunistic pathogen cryptosporidium parvum. | cryptosporidium parvum is one of the major causes of waterborne diseases worldwide. this protozoan parasite depends mainly on the anaerobic oxidation of glucose for energy production. in order to identify the differences in the three-dimensional structure of key glycolytic enzymes of c. parvum and its human host, we have expressed, purified and crystallized recombinant versions of three important glycolytic enzymes of the parasite, namely, glyceraldehyde 3-phosphate dehydrogenase, pyruvate kinas ... | 2005 | 15953771 |
| 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 ... | 2005 | 15955631 |
| unique endemicity of cryptosporidiosis in children in kuwait. | to understand the transmission of cryptosporidium infection in children, fecal specimens from 62 kuwaiti children with gastrointestinal symptoms found to be positive by microscopy were genotyped and subtyped with a small subunit rrna-based pcr-restriction fragment length polymorphism analysis and a 60-kda glycoprotein-based dna sequencing tool. the median age of infected children was 4.5 years, and 77% of infections occurred during the cool season of november to april. fifty-eight of the childre ... | 2005 | 15956401 |
| 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. | 2005 | 15960665 |
| development of a ct equation taking into consideration the effect of lot variability on the inactivation of cryptosporidium parvum oocysts with ozone. | cryptosporidium parvum oocysts are prevalent in surface water and ground water under the influence of surface water, and are difficult to inactivate using free chlorine, the most common disinfectant currently used for treating drinking water. in contrast, it has been shown that ozone is a more effective disinfectant than chlorine. us epa is currently evaluating a treatment rule, which addresses the control of c. parvum oocysts in drinking water. the use of ct (average disinfectant concentration ... | 2005 | 15963550 |
| local peroxynitrite formation contributes to early control of cryptosporidium parvum infection. | in intestinal inflammation, mucosal injury is often exacerbated by the reaction of no with neutrophil-derived superoxide to form the potent oxidant peroxynitrite. peroxynitrite also has antimicrobial properties that aid in the killing mechanism of macrophages and neutrophils. cryptosporidium parvum parasitizes intestinal epithelium, resulting in loss of epithelial cells and mucosal inflammation. synthesis of no is significantly increased and arises from the induced expression of inducible nitric ... | 2005 | 15972479 |
| 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 ... | 2005 | 15979802 |
| effect of lot variability on ultraviolet radiation inactivation kinetics of cryptosporidium parvum oocysts. | numerous studies have demonstrated the efficiency of ultraviolet (uv) radiation for the inactivation of oocysts of cryptosporidium parvum. in these studies inactivation is measured as reduction in oocysts. a primary goal is to estimate the uv radiation required to achieve a high degree of inactivation. different lots of cryptosporidium parvum oocysts are used in these studies, and the inactivation rate may vary depending on the lot of oocysts used. the goal of this paper is to account for the er ... | 2005 | 15984796 |
| 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 ... | 2005 | 15986633 |
| detection of cryptosporidium parvum oocysts in experimentally contaminated lettuce using filtration, immunomagnetic separation, light microscopy, and pcr. | recovery of cryptosporidium parvum oocysts in a fecal suspension that experimentally contaminated onto lettuce leaves was investigated. material recovered from the lettuce samples by washing in detergent solutions were concentrated by filtration using the envirochek sampling capsule. oocysts were concentrated by immunomagnetic separation (ims) and detected by microscopy following modified ziehl-neelsen (mzn) staining. cryptosporidal dna was detected using a nested-pcr assay for amplification of ... | 2004 | 15992283 |
| new genotypes and factors associated with cryptosporidium detection in mussels (mytilus spp.) along the california coast. | a 3 year study was conducted to evaluate mussels as bioindicators of faecal contamination in coastal ecosystems of california. haemolymph samples from 4680 mussels (mytilus spp.) were tested for cryptosporidium genotypes using pcr amplification and dna sequence analysis. our hypotheses were that mussels collected from sites near livestock runoff or human sewage outflow would be more likely to contain the faecal pathogen cryptosporidium than mussels collected distant to these sites, and that the ... | 2005 | 15993883 |
| 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 ... | 2005 | 15997405 |
| [opportunistic protozoa--the problem in immunodeficient patients]. | protozoan infections with a mild or asymptomatic course in immunocompetent individuals, in the case of immunocompromised patients could cause severe syndromes or fatal outcome. the different clinical course is possible to diagnose only with specific laboratory methods. actual settlements on the most often diagnosed in human opportunistic protozoan infections pathogenesis and diagnostics are presented. | 2005 | 15997648 |
| synergistic inactivation of cryptosporidium parvum using ozone followed by monochloramine in two natural waters. | the effect of sequential exposure to ozone followed by monochloramine on inactivation of cryptosporidium parvum oocysts suspended in untreated natural surface water from two different sources was studied in bench-scale batch reactors. animal infectivity using neonatal cd-1 mice was used to measure oocyst inactivation. a statistically significant synergistic effect on oocyst inactivation was measured in both natural water samples studied. the magnitude of the effect measured in the natural water ... | 2005 | 16000207 |
| environmental temperature controls cryptosporidium oocyst metabolic rate and associated retention of infectivity. | cryptosporidium is a significant cause of water-borne enteric disease throughout the world and represents a challenge to the water industry and a threat to public health. in this study we report the use of a cell culture-taqman pcr assay to measure oocyst inactivation rates in reagent-grade and environmental waters over a range of temperatures. while oocysts incubated at 4 degrees c and 15 degrees c remained infective over the 12-week holding period, we observed a 4 log(10) reduction in infectiv ... | 2005 | 16000797 |
| functional characterization of an evolutionarily distinct phosphopantetheinyl transferase in the apicomplexan cryptosporidium parvum. | recently, two types of fatty acid synthases (fass) have been discovered from apicomplexan parasites. although significant progress has been made in characterizing these apicomplexan fass, virtually nothing was previously known about the activation and regulation of these enzymes. in this study, we report the discovery and characterization of two distinct types of phosphopantetheinyl transferase (pptase) that are responsible for synthesizing holo-acyl carrier protein (acp) from three apicomplexan ... | 2005 | 16002647 |
| pulmonary cryptosporidiosis in an aids patient: successful treatment with paromomycin plus azithromycin. | extra-intestinal cryptosporidiosis, especially of the biliary and respiratory tract, is likely in the course of an intestinal involvement, whereas it is rare without such a localization. we report a case of pulmonary cryptosporidiosis without apparent intestinal involvement in an aids patient, with favourable outcome after antimicrobial combination therapy with paromomycin plus azithromycin. the successful response to antimicrobial treatment was subsequently maintained by effective highly active ... | 2005 | 16004637 |
| use of nitazoxanide as a new therapeutic option for persistent diarrhea: a pediatric perspective. | despite advances in the management of diarrheal disorders, diarrhea is the second most frequent illness in the world. persistent diarrhea, common in community pediatrics, is often caused by organisms such as giardia lamblia, cryptosporidium parvum and, less frequently, cyclospora, isospora belli, and clostridium difficile. identifying the causative organism is often challenging, and diagnostic tests may be inaccurate and expensive and, thus, of limited benefit. consequently, carefully chosen emp ... | 2005 | 16004666 |
| treatment of cryptosporidiosis in immunocompromised hosts. | the most important species of cryptosporidium in humans, c. parvum and c. hominis, cause severe and chronic life-threatening gastroenteritis in immunocompromised patients. despite a certain efficacy shown by passive immunotherapy or by some chemotherapeutic agents (e.g. paromomycin and nitazoxanide), no significant benefit has been demonstrated. the use of highly active antiretroviral therapy (haart) in persons with the acquired immunodeficiency syndrome drastically reduces the prevalence of cry ... | 2005 | 16006765 |
| the protozoan parasite cryptosporidium parvum possesses two functionally and evolutionarily divergent replication protein a large subunits. | very little is known about protozoan replication protein a (rpa), a heterotrimeric complex critical for dna replication and repair. we have discovered that in medically and economically important apicomplexan parasites, two unique rpa complexes may exist based on two different types of large subunit rpa1. in this study, we characterized the single-stranded dna binding features of two distinct types (i.e. short and long) of rpa1 subunits from cryptosporidium parvum (cprpa1a and cprpa1b). these tw ... | 2005 | 16014411 |
| [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 ... | 2005 | 16028484 |
| evaluation of colostrum and whey-derived gamma globulins for prevention of cryptosporidiosis in artificially infected neonatal calves. | thirty colostrum-deprived friesian male calves were used to study the effect of colostrum and whey-derived gammaglobulins on the clinical events and oocyst-excretion pattern following artificial infection with a fresh, field-sourced strain of cryptosporidium parvum. the calves were raised naive and free from contact with c. parvum from birth until infection at either 10 or 17 days of age. the two age groups comprised three sub-groups that were each given a single treatment of colostrum, whey-der ... | 1996 | 16031922 |
| a dance teacher with kidney-pancreas transplant and diarrhoea: what is the cause? | | 2005 | 16033769 |
| recombinant proteins of cryptosporidium parvum induce proliferation of mesenteric lymph node cells in infected mice. | recombinant antigens of cryptosporidium parvum, cp900 and cp40 but not cp15, stimulated c. parvum-specific proliferative immune responses of mesenteric lymph node cells in c57bl/6j mice infected with different isolates (md, gch1, ucp, and iowa) of c. parvum, indicating that both cp900 and cp40 are immunodominant targets of cellular immune responses during c. parvum infection. | 2005 | 16041049 |
| infectivity of cryptosporidium hominis and cryptosporidium parvum genotype 2 isolates in immunosuppressed mongolian gerbils. | one-month-old dexamethasone-immunosuppressed mongolian gerbils were challenged with 1 oocyst to 2 x 10(5) oocysts from two isolates genotyped as cryptosporidium hominis and c. parvum (genotype 2), respectively. a similar dose-dependent gut infection was obtained, and the initial genotype maintained for 21 to 22 days. the data suggest that immunosuppressed gerbils provide a reliable rodent model of persistent c. hominis infection. | 2005 | 16041051 |
| prediction of the general transcription factors associated with rna polymerase ii in plasmodium falciparum: conserved features and differences relative to other eukaryotes. | to date, only a few transcription factors have been identified in the genome of the parasite plasmodium falciparum, the causative agent of malaria. moreover, no detailed molecular analysis of its basal transcription machinery, which is otherwise well-conserved in the crown group of eukaryotes, has yet been reported. in this study, we have used a combination of sensitive sequence analysis methods to predict the existence of several parasite encoded general transcription factors associated with rn ... | 2005 | 16042788 |
| 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 ... | 2005 | 16047784 |