Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| long-term survival of cryptosporidium parvum oocysts in seawater and in experimentally infected mussels (mytilus galloprovincialis). | transmission of infectious oocysts of cryptosporidium parvum via surface- and drinking-water supplies has been reported and many surface waters flow into the sea, potentially causing runoff of animal-infected faeces. eating raw mussels is a common practice in many countries, increasing the public's risk of acquiring enteric pathogens. the aims of the present study were to estimate how long c. parvum oocysts remain infectious in artificial seawater, to determine if the oocysts are retained in mus ... | 1999 | 10404265 |
| identification and characterisation of three antigenic proteins from cryptosporidium parvum sporozoites using a dna library expressing poly-histidine tagged peptides. | to identify antigenic peptides of the parasite cryptosporidium parvum, an expression library that allows for the production of chimeric proteins fused with a 6-histidine tag was made. the library was screened with c. parvum sporozoite rabbit anti-serum, and three positive clones (sa20, sa35, and sa40) were identified. the corresponding recombinant proteins (sa20, sa35, and sa40) were expressed in escherichia coli and purified by metal-affinity chromatography. the sequence of sa20 and sa35 clones ... | 1999 | 10961848 |
| sacroiliitis associated with cryptosporidium parvum in an hla-b27-negative patient. | 1999 | 10325675 | |
| evidence of thymus-independent local and systemic antibody responses to cryptosporidium parvum infection in nude mice. | differences in susceptibility to persistent cryptosporidial infection between two strains of adult athymic nude mice prompted us to investigate the immune mechanism(s) that may control resistance to infection in these t-cell-deficient mice. we studied fecal oocyst shedding, serum and fecal parasite-specific antibody responses, and fecal immunoglobulin levels in athymic c57bl/6j nude and athymic balb/cj nude mice following oral inoculation with cryptosporidium parvum oocysts at 8 to 9 weeks of ag ... | 1999 | 10417160 |
| efficacy of treatment with paromomycin, azithromycin, and nitazoxanide in a patient with disseminated cryptosporidiosis. | a 24-year-old hiv-positive heterosexual woman with disseminated cryptosporidiosis was monitored from january 1998 to may 1999. during this period, consecutive stool, sputum, and bile examinations showed the constant presence of cryptosporidium oocysts. although the patient was repeatedly treated with oral paromomycin and azithromycin and, finally, nitazoxanide, her condition continued to deteriorate. in order to monitor the in vitro susceptibility of the parasite, specimens from various sites we ... | 1999 | 10691200 |
| case of cryptosporidiosis in an iraqi woman with ulcerative colitis. | 1999 | 10793796 | |
| three sample preparation protocols for polymerase chain reaction based detection of cryptosporidium parvum in environmental samples. | cryptosporidium parvum is a protozoan parasite responsible for an increasing number of outbreaks of gastrointestinal illness worldwide. in this report, we describe development of sample preparation protocols for polymerase chain reaction (pcr)-based detection of c. parvum in fecal material and environmental water samples. two of these methods were found adequate for isolation of cryptosporidium dna from filtered water pellet suspensions. the first involved several filtration steps, immunomagneti ... | 1999 | 10076632 |
| [a new trichromic safranin stain for the detection of cryptosporidium parvum, cyclospora cayetanensis, species of microsporidia and isospora belli in fecal material]. | cryptosporidium parvum, isospora belli, cyclospora cayetanensis and microsporidia are frequent pathogens in the immunodeficient host, which may cause multiple infections. the above mentioned parasites are found in feces by the application of different specific tintorial techniques. the objective of this work was the development of a stain for the simultaneous detection of these parasites, reducing costs as well as the time taken to make the diagnosis. the safranin-trichrome stain is simple, chip ... | 1999 | 10932763 |
| cryptosporidium parvum prevalence in a group of turkish children. | stool samples from two hundred children with diarrhea and from 50 healthy children were examined, by modified kinyoun's acid-fast staining (maf), giemsa staining and direct (dfa) and indirect immunofluorescence antibody (ifa) methods, in order to determine cryptosporidiosis prevalence under the age of 12 and to detect the most efficient identifying method for use in our country. cryptosporidium oocysts were detected in seven (3.5%) of the cases. none of the samples from the control subjects was ... | 1999 | 10770657 |
| sequence of the gene encoding hsp90e from cryptosporidium parvum. | a composite 2364 nt dna sequence with an open reading frame (orf) encoding an endoplasmic reticulum-associated heat shock protein 90 (cphsp90e) was determined from clones isolated from genomic libraries constructed from the ksu-1 isolate of cryptosporidium parvum. transcription was verified by isolation of a clone from a cdna library with a similar restriction map to that observed with genomic dna. the predicted protein consists of 787 amino acids, has a predicted molecular size of 89.2 kda, and ... | 1999 | 10727089 |
| cryptosporidium parvum studies with dairy products. | cryptosporidium parvum is a protozoan parasite capable of causing massive waterborne outbreaks. this study was conducted to model the transfer of c. parvum oocysts from contaminated water via food contact surfaces into yogurt and ice-cream, as well as to examine oocyst survival. propidium iodide staining, combined with a direct immunofluorescence assay, was used for oocyst viability determination. oocysts were recovered from milk products by a sucrose flotation-based procedure, with average reco ... | 1999 | 10728612 |
| use of a sentinel system for field measurements of cryptosporidium parvum oocyst inactivation in soil and animal waste. | a small-volume sentinel chamber was developed to assess the effects of environmental stresses on survival of sucrose-percoll-purified cryptosporidium parvum oocysts in soil and animal wastes. chambers were tested for their ability to equilibrate with external chemical and moisture conditions. sentinel oocysts were then exposed to stresses of the external environment that affected their viability (potential infectivity), as indicated by results of a dye permeability assay. preliminary laboratory ... | 1999 | 10223991 |
| survey on equine cryptosporidiosis in poland and the possibility of zoonotic transmission. | the present study was undertaken to investigate the prevalence of cryptosporidium infection in horses used for recreational riding as well as in humans. a total of 106 faecal specimens from horses raised in 4 localities of western poland and 6 stool samples from 3 persons who had constant or sporadic contact with horses were screened microscopically for oocysts using modified ziehl-neelsen staining. enzyme immunoassay (eia) was additionally used for the detection of coproantigen in human stool s ... | 1999 | 10607998 |
| antimicrobial activity of polycationic peptides. | the in vitro activity of six polycationic peptides, buforin ii, cecropin p1, indolicidin, magainin ii, nisin, and ranalexin, were evaluated against several clinical isolates of gram-positive and gram-negative aerobic bacteria, yeasts, pneumocystis carinii and cryptosporidium parvum, by using microbroth dilution methods. the peptides exhibited different antibacterial activities and rapid time-dependent killing. the gram-negative organisms were more susceptible to buforin ii and cecropin p1, where ... | 1999 | 10612440 |
| association of herd composition, stocking rate, and duration of calving season with fecal shedding of cryptosporidium parvum oocysts in beef herds. | to evaluate the association of herd demographics, parturition variables, stocking rate, and rotational grazing practices with the probability of fecal shedding of cryptosporidium parvum from beef cow-calf herds in california. | 1999 | 10613218 |
| in vitro anticryptosporidial activity of ranalexin alone and in combination with other peptides and with hydrophobic antibiotics. | the in vitro activity of ranalexin alone and in combination with other cationic peptides, macrolides, rifampin, and rifabutin was investigated against a clinical isolate of cryptosporidium parvum. susceptibility tests were performed by inoculation of the isolate onto cell monolayers and determining the parasite count after 48 h of incubation at 37 degrees c. antibiotic-free cultures were used as controls in the study. ranalexin showed low anticryptosporidial activity: it suppressed the growth of ... | 1999 | 10614961 |
| caspase-dependent apoptosis during infection with cryptosporidium parvum. | the protozoan parasite cryptosporidium parvum causes persistent diarrhea and malnutrition in children and the diarrhea-wasting syndrome in aids. no therapy exists for eliminating the parasite in the absence of a healthy immune response. although it had been reported that infection of intestinal cell lines with c. parvum leads to host cell death, the mechanisms of cytolysis have not been characterized. we show here that infection with c. parvum leads to typical apoptotic nuclear condensation and ... | 1999 | 10580271 |
| nosocomial infections in patients with hiv disease. | throughout the aids epidemic, nosocomial infection in the patient with hiv disease has presented a constant problem--not only for the hospitalized patient but also for the clinic attender. the nosocomial spread of multidrug-resistant tuberculosis has emphasized the need for effective control of infection measures in dealing with the immunodeficient. increased recognition of nosocomial bacterial pneumonias has raised questions about the place, if any, of antimicrobial prophylaxis in preventing gr ... | 1999 | 10582184 |
| molecular analysis of the 18s rrna gene of cryptosporidium serpentis in a wild-caught corn snake (elaphe guttata guttata) and a five-species restriction fragment length polymorphism- based assay that can additionally discern c. parvum from c. wrairi. | an adult wild-caught corn snake (elaphe guttata guttata) was presented for humane euthanasia and necropsy because of severe cryptosporidiosis. the animal was lethargic and >5% dehydrated but in good flesh. gastric lavage was performed prior to euthanasia. histopathologic findings included gastric mucosal hypertrophy and a hemorrhagic erosive gastritis. numerous 5- to 7-microm-diameter round extracellular organisms were associated with the mucosal hypertrophy. a pcr, acid-fast stains, giemsa stai ... | 1999 | 10583987 |
| nasal immunization of mice with cryptosporidium parvum dna induces systemic and intestinal immune responses. | dna immunization offers a novel approach to inducing humoral and cellular immunity against infectious pathogens. we examined whether such an approach could be used against cryptosporiodiosis, an intestinal disease caused by the protozoan parasite cryptosporidium parvum. this infection is a major problem for young ruminants and immunosuppressed individuals in whom cryptosporidiosis causes life-threatening symptoms. the life cycle of c. parvum takes place in the enterocytes of the intestinal epith ... | 1999 | 10587377 |
| characterization of intracellular cryptosporidium parvum gene expression. | 1999 | 10589988 | |
| comparison of fecal samples collected per rectum and off the ground for estimation of environmental contamination attributable to beef cattle. | to determine whether sampling feces off the ground replicates prevalence estimates for specific pathogens obtained from fecal samples collected per rectum of adult cows, and to determine characteristics of feces on the ground (fecal pats) that are associated with subsequent identification of campylobacter spp, cryptosporidium parvum, and giardia duodenalis. | 1999 | 10566807 |
| cryptosporidium infection in beech martens (martes foina). | temporary episodes of diarrhea in captive beech martens (martes foina) were accompanied by shedding of cryptosporidium oocysts. oocysts were detected in fecal samples by flotation and in acid-fast-stained smear preparations. the oocysts were 3-5 microns, which is consistent with c. parvum. the source of the cryptosporidium infection remained unknown. this is the first demonstration of cryptosporidium in beech martens. | 1999 | 10572868 |
| the norway rat as a reservoir host of cryptosporidium parvum. | the potential of norway rats (rattus norvegicus) to spread the parasite cryptosporidium parvum was investigated by examining parasite prevalence in relation to the structure and movements of three permanent rat populations living on farmland in warwickshire (uk) from october 1994 to march 1997. one population lived among a group of farm buildings housing cattle, while the other two had no contact with livestock, one living around a pond and its outflowing stream and the other on a rubbish tip. o ... | 1999 | 10574524 |
| prevalence of intestinal parasitic infections in patients with acquired immunodeficiency syndrome in brazil. | to evaluate the prevalence of intestinal parasitic infections and to investigate the possible associations of clinical status and laboratory findings with the different parasites found in stool samples. | 1999 | 10575149 |
| the identification of cryptosporidium species and cryptosporidium parvum directly from whole faeces by analysis of a multiplex pcr of the 18s rrna gene and by pcr/rflp of the cryptosporidium outer wall protein (cowp) gene. | a multiplex polymerase chain reaction (pcr) procedure to amplify 18s rrna gene fragments has been developed. amplified dna fragments of the expected size were obtained which were specific for cryptosporidium parvum and cryptosporidium wrairi (422 bp), cryptosporidium baileyi (11106 bp) and cryptosporidium muris (1346 bp). criptosporidium parvum and c. wrairi can be distinguished using a pcr/restriction fragment length polymorphism (rflp) analysis of the cryptosporidium outer wall protein (cowp) ... | 1999 | 10576575 |
| ultrastructure, fractionation and biochemical analysis of cryptosporidium parvum sporozoites. | sporozoites of the apicomplexan parasite cryptosporidium parvum were subjected to cell disruption and subcellular fractionation using a sucrose density step gradient. with this procedure, highly enriched preparations of the parasite membrane, the micronemes, dense granules and amylopectin granules were produced. no separate fraction containing rhoptries was obtained, however this organelle was found in defined fractions of the gradient, still associated with the apical tip of the sporozoites. us ... | 1999 | 10576576 |
| role of adult sheep in transmission of infection by cryptosporidium parvum to lambs: confirmation of periparturient rise. | in sheep farms, oocyst shedding by asymptomatic adult carriers is one of the mechanisms which may explain maintenance of infections by cryptosporidium parvum between lambing periods. the objective of this work was to investigate this hypothesis and the existence of a periparturient rise in oocyst shedding. fourteen pregnant sheep were randomly selected from two farms with a history of neonatal diarrhoea caused by c. parvum and samples were collected from the 6th week before birth until 2 weeks a ... | 1999 | 10576577 |
| a review of the importance of cryptosporidiosis in farm animals. | cryptosporidium species are coccidian parasites with a large capacity to reproduce and to disseminate. several species are known to infect farm animals, although the economic importance of cryptosporidiosis is highly host species dependent. this paper reviews the impact of cryptosporidial infections in livestock and poultry. for different farm animals, the cryptosporidium spp. that occur, as well as their clinical and pathological features, and their interactions with other pathogens, are descri ... | 1999 | 10576578 |
| speculation on whether a vaccine against cryptosporidiosis is a reality or fantasy. | in this paper the authors question whether the development of a vaccine against cryptosporidiosis could be taken into consideration. the necessity and feasibility of such a vaccine for human and veterinary application is discussed. developmental stages within the life cycle of the parasite that might act as possible targets for vaccine development are summarised, as well as the target antigens offered by molecular biology and immunology studies. vaccination trials against cryptosporidiosis carri ... | 1999 | 10576579 |
| atypical outbreak of caprine cryptosporidiosis in the sultanate of oman. | an outbreak of cryptosporidiosis occurred in goats ranging in age from two days to adult, on a well-managed closed farm. none of the other animals on the farm, including sheep, cows and buffalo, were affected. morbidity approached 100 per cent in goats less than six months of age. despite intensive supportive care, 238 goats died, ranging in age from two days to over one year. cryptosporidia were detected in large numbers in the intestinal contents of dead animals and in faecal smears of animals ... | 1999 | 10576626 |
| cryptosporidium parvum: structural components of the oocyst wall. | cryptosporidium parvum, an enteropathogenic parasite, infects a wide range of mammals including man and constitutes a substantial veterinary and medical threat due to its ubiquitous distribution and the stability of the oocyst stage. the oocyst wall of c. parvum is known to be extremely resistant to chemical and mechanical disruption. isolated oocyst walls are shown by both thin sectioning and negative staining transmission electron microscopy to possess a filamentous array on the inner surface. ... | 1999 | 10577718 |
| oral dosing of neonatal mice with sucrose reduces infection with cryptosporidium parvum. | cryptosporidium parvum is a significant cause of diarrheal disease in humans and economically important livestock species. there is no effective treatment available for this protozoan parasite. mechanisms of intestinal colonization by c. parvum are not well understood, but it has been suggested that the parasite may utilize a lectin-like receptor. we used an infant mouse model to test whether high sugar concentrations in the intestine would affect in vivo colonization with c. parvum. we found th ... | 1999 | 10577733 |
| polymorphisms in the beta-tubulin gene of cryptosporidium parvum differentiate between isolates based on animal host but not geographic origin. | polymerase chain reaction primers were designed to target a region of the cryptosporidium parvum beta-tubulin gene spanning an intron. amplification products contained 11 polymorphic positions, representing a sequence divergence of 1.8%, which discriminated between isolates of c. parvum found solely in humans (genotype 1) and those found in humans and animals (genotype 2). seven of the polymorphic sites were located outside of the intron and the polymorphism between isolates was readily demonstr ... | 1999 | 10577745 |
| cryptosporidium parvum apical complex glycoprotein csl contains a sporozoite ligand for intestinal epithelial cells. | cryptosporidiosis, caused by the apicomplexan parasite cryptosporidium parvum, has become a well-recognized diarrheal disease of humans and other mammals throughout the world. no approved parasite-specific drugs, vaccines, or immunotherapies for control of the disease are currently available, although passive immunization with c. parvum-specific antibodies has some efficacy in immunocompromised and neonatal hosts. we previously reported that csl, an approximately 1,300-kda conserved apical glyco ... | 1999 | 10496907 |
| receptor/ligand interactions between cryptosporidium parvum and the surface of the host cell. | the ability of membrane antigens on sporozoites of the intestinal pathogen, cryptosporidium parvum, to bind host cell surface antigens was investigated. a novel membrane-associated protein of approximately 47 kda, designated cp47, was found to possess significant binding affinity for the surface of both human and animal ileal cells. this protein was purified by a combination of anion-exchange chromatography on fplc and immunoaffinity chromatography. purified cp47 demonstrated competitive binding ... | 1999 | 10381561 |
| epidemiology of cryptosporidium parvum in symptomatic paediatric oncology patients. | although cryptosporidium parvum is known to cause significant morbidity in immunocompromised individuals, including adults with cancer, the epidemiology of this pathogen in paediatric oncology patients is not known. | 1999 | 10404455 |
| biochemical peculiarities and drug targets in cryptosporidium parvum: lessons from other coccidian parasites. | there is an urgent need for effective medicines for treating human and animal cryptosporidiosis. in the absence of drugs being found using an empirical route, the structure-based approach may be the better option for discovering new chemotherapeutic agents against these diseases. with this objective, what possible drug targets are there? here, graham coombs speculates on the best putative targets for chemotherapeutic attack, and reviews what is known and what can be deduced about the biochemical ... | 1999 | 10407381 |
| nested pcr for the detection of cryptosporidium parvum. | 1999 | 10407384 | |
| the fate of cryptosporidium parvum oocysts ingested by dung beetles and their possible role in the dissemination of cryptosporidiosis. | the fate of oocysts of cryptosporidium parvum ingested by dung beetles and the possible role these beetles serve in the dissemination of cryptosporidiosis were tested on the following species: anoplotrupes stercorosus, aphodius rufus, and onthophagus fracticornis. ten specimens of each species were offered cattle dung supplemented with 5.9 x 10(6) oocysts of c. purvum. after 24 hr of feeding, the beetles were examined for the presence of oocysts on their external surfaces, in their gastrointesti ... | 1999 | 10461948 |
| serological differences in neospora caninum-associated epidemic and endemic abortions. | a sandwich enzyme-linked immunosorbent assay (elisa) for the sensitive and specific detection of bovine antibodies to neospora caninum was developed and evaluated using sera from cattle experimentally infected with n. caninum, toxoplasma gondii, sarcocystis cruzi, sarcocystis hominis, sarcocystis hirsuta, eimeria bovis, cryptosporidium parvum, babesia divergens, and field sera from naturally exposed animals. field sera were classified using a gold standard that included the results from an indir ... | 1999 | 10461950 |
| accumulation of mucosal t lymphocytes around epithelial cells after in vitro infection with cryptosporidium parvum. | we had previously shown that ileal intraepithelial lymphocytes isolated from calves with cryptosporidiosis include significantly increased numbers of cd8+ t lymphocytes and activated cd4+ cells. these increases could result from redistribution of resident mucosal lymphocytes or from homing of peripheral t cells to ileal mucosa. to determine whether resident mucosal lymphocytes can redistribute to cryptosporidium parvum-infected epithelium, oocysts were inoculated in vitro onto ileum explants tak ... | 1999 | 10461968 |
| intestinal parasites in malaysian children with cancer. | in this prospective study, we examined stool specimens from children with cancer receiving chemotherapy who were admitted for fever to the universiti sains malaysia hospital in kota baru, kelantan. stool specimens were examined for ova and cysts of parasites. over a period of 15 months, there were 129 febrile episodes in 50 children with cancer and, in all, 237 stool specimens were examined. sixty-six per cent of febrile episodes were associated with neutropenia and 9 per cent were associated wi ... | 1999 | 10467838 |
| a most-probable-number assay for enumeration of infectious cryptosporidium parvum oocysts. | cryptosporidium is globally established as a contaminant of drinking and recreational waters. a previously described cell culture infectivity assay capable of detecting infectious oocysts was adapted to quantify viable oocysts through sporozoite invasion and clustering of foci. eight experiments were performed by using oocysts less than 4 months of age to inoculate host hct-8 cell monolayers. oocysts were diluted in a standard 5- or 10-fold multiple dilution format, levels of infection and clust ... | 1999 | 10473398 |
| detection of viral pathogens by reverse transcriptase pcr and of microbial indicators by standard methods in the canals of the florida keys. | in order to assess the microbial water quality in canal waters throughout the florida keys, a survey was conducted to determine the concentration of microbial fecal indicators and the presence of human pathogenic microorganisms. a total of 19 sites, including 17 canal sites and 2 nearshore water sites, were assayed for total coliforms, fecal coliforms, escherichia coli, clostridium perfringens, enterococci, coliphages, f-specific (f(+)) rna coliphages, giardia lamblia, cryptosporidium parvum, an ... | 1999 | 10473424 |
| virulence of three distinct cryptosporidium parvum isolates for healthy adults. | the infectivity of three cryptosporidium parvum isolates (iowa [calf], ucp [calf], and tamu [horse]) of the c genotype was investigated in healthy adults. after exposure, volunteers recorded the number and form of stools passed and symptoms experienced. oocyst excretion was assessed by immunofluorescence. the id50 differed among isolates: iowa, 87 (se, 19; 95% confidence interval [ci], 48.67-126); ucp, 1042 (se, 1000; 95% ci, 0-3004); and tamu, 9 oocysts (se, 2.34; 95% ci, 4.46-13.65); tamu vers ... | 1999 | 10479158 |
| [prevalence and importance of endoparasites in calves raised in swiss cow-calf farms]. | a longitudinal study was performed to establish estimates of prevalence of selected endoparasites in swiss cow-calf operations and to investigate the importance of an infection with endoparasites on diarrhea and weight gain until weaning. three hundred and eighty-six calves raised in 67 larger cow-calf herds were included in the study. faecal samples were collected during the first three months of life and at weaning. parasitological analyses were performed according to standard procedures inclu ... | 1999 | 10481370 |
| cryptosporidium parvum induces apoptosis in biliary epithelia by a fas/fas ligand-dependent mechanism. | although the clinical features of sclerosing cholangitis from opportunistic infections of the biliary tree in patients with acquired immunodeficiency syndrome (aids) are well known, the mechanisms by which associated pathogens, such as cryptosporidium parvum, cause disease are obscure. using an in vitro model of biliary cryptosporidiosis, we observed that c. parvum induces apoptosis in cultured human biliary epithelia. both caspase protease inhibitors and neutralizing antibodies to either fas re ... | 1999 | 10484385 |
| in situ reverse transcription for the specific detection of bacteria and protozoa. | in situ hybridization experiments with oligonucleotide probes directed against the 16s and 18s rrna molecules have been used successfully to identify specific organisms in mixed microbial populations. however, there are limitations in applying these techniques to environmental samples. in the present study we have examined the possibility of using in situ reverse transcription as an alternative to hybridization methods for the rapid detection of escherichia coli and the waterborne parasite crypt ... | 1999 | 10664984 |
| cryptosporidium sp. and giardia sp. infections in mountain gorillas (gorilla gorilla beringei) of the bwindi impenetrable national park, uganda. | for conservation purposes and because of growing ecotourism, some mountain gorilla (gorilla gorilla beringei) populations have been habituated to humans. fecal specimens (n = 100) of nonhabituated and human-habituated gorillas (5 populations; 6 age classes) were tested for cryptosporidium sp. oocysts and giardia sp. cysts by conventional staining and immunofluorescent antibody (ifa). cryptosporidium sp. infections (prevalence 11%) were not restricted to very young gorillas but were observed in 3 ... | 1999 | 10647041 |
| cryptosporidium parvum-induced inflammatory bowel disease of tcr-beta- x tcr-delta-deficient mice. | experimental inoculation of neonatal immunocompetent strains of mice with cryptosporidium parvum results in a transient, noninflammatory enteric infection. in the present study, we show that inoculation of mice deficient in alphabeta and gammadelta t cells (tcr-beta- x tcr-delta-deficient mice) with c. parvum results in persistent infection and severe inflammatory bowel disease-like lesions. the most severe lesions in these mice were in the cecum with similar yet less severe lesions in the ileum ... | 1999 | 10647043 |
| phylogenetic relationships among isolates of cryptosporidium: evidence for several new species. | isolates of cryptosporidium were characterized using nucleotide sequence analysis of the 18s rrna and dihydrofolate reductase genes and also random-amplified polymorphic dna analysis. phylogenetic analysis confirmed the validity of the species of cryptosporidium examined in this study such as cryptospordium muris and cryptosporidium baileyi, and also reinforced evidence from numerous researchers worldwide suggesting that cryptosporidium parvum is not a single uniform species. the data obtained p ... | 1999 | 10647047 |
| a comparison of enumeration techniques for cryptosporidium parvum oocysts. | a variety of methods have been used to enumerate cryptosporidium parvum oocysts from source or drinking waters. the reliability of these counting methods varies, in part, with suspension density, sample purity, and other factors. frequently, the method of determination of suspension density is not reported by authors. to confound the problem, each method of counting has large inherent variation. there is a relationship between suspension density, overall number of organisms counted, and counting ... | 1999 | 10647050 |
| effect of salinity, temperature and storage time on mouse experimental infection by cryptosporidium parvum. | cryptosporidium parvum oocysts collected from a naturally infected calf were exposed to different salinity and temperature for 2, 21 and 40 days, and then inoculated intragastrically into coccidium-free neonatal mice. the intensity of infection as determined seven days later by examination of intestinal homogenates were statistically analysed. salinity, time and salinity-time interaction were the only factors with significant effect on the infection intensity. | 1999 | 10628695 |
| intestinal protozoa in hiv-infected patients: effect of rifaximin in cryptosporidium parvum and blastocystis hominis infections. | in hiv-1 infected patients severe enteritis and chronic diarrhea are often documented as a consequence of multiple opportunistic infections. we analyzed 48 hiv-1 positive patients for the presence of intestinal pathogenic protozoa. patients with cd4 > or = 200/mm3 showed a higher prevalence of a single pathogenic protozoa than patients with cd4 < or =200/mm3, who showed the presence of multiple protozoal infections. patients who proved positive for only a single protozoa, cryptosporidium or blas ... | 1999 | 10632386 |
| immunodetection of the microvillous cytoskeleton molecules villin and ezrin in the parasitophorous vacuole wall of cryptosporidium parvum (protozoa: apicomplexa). | microvilli - actin - villin - ezrin - cryptosporidium parvum the sporozoites and merozoites of the apicomplexan protozoan cryptosporidium parvum (c. parvum) invade the apical side of enterocytes and induce the formation of a parasitophorous vacuole which stays in the brush border area and disturbs the distribution of microvilli. the vacuole is separated from the apical cytoplasm of the cell by an electron-dense layer of undetermined composition. in order to characterize the enterocyte cytoskelet ... | 1999 | 10604656 |
| genomic characterisation of the large segment of a rabbit picobirnavirus and comparison with the atypical picobirnavirus of cryptosporidium parvum. | the 2362 base pair sequence of the larger of the two double stranded rna genome segments of a rabbit strain of picobirnavirus (pbv) has a major open reading frame (orf) of 591 amino acids and two smaller orfs of 55 and 155 amino acids. a clone of the segment did not hybridise with other viral bisegmented ds rnas from faecal samples. there is no relationship in sequence or organisation between this pbv sequence and the bisegmented dsrnas found associated with cryptosporidium parvum. this suggests ... | 1999 | 10664398 |
| cryptosporidium parvum gene discovery. | cryptosporidium parvum is a well-recognized cause of diarrhea in humans and animals throughout the world, and is associated with a substantial degree of morbidity and mortality in patients with acquired immunodeficiency syndrome (aids). at the present time, there is no effective therapy for treating or preventing infection with c. parvum. this is primarily due to a lack of understanding of the basic cellular and molecular biology of this pathogen in terms of virulence factors, genome structure, ... | 1999 | 10659365 |
| assessment of drugs against cryptosporidium parvum using a simple in vitro screening method. | a rapid semi-quantitative screening method was devised for assessing the anticryptosporidial and cytotoxic effects of putative chemotherapeutic compounds. the method is suitable as an initial rapid screening procedure from which compounds demonstrating anticryptosporidial activity can be identified for further analysis. it has the advantages of speed, low cost and concurrent assessment of anticryptosporidial and cytotoxic effects and allows accurate determination of minimum lethal concentrations ... | 1999 | 10499272 |
| monitoring not the answer to cryptosporidium in water. | 1999 | 10501354 | |
| evaluation of cryptosporidium parvum genotyping techniques. | we evaluated the specificity and sensitivity of 11 previously described species differentiation and genotyping pcr protocols for detection of cryptosporidium parasites. genomic dna from three species of cryptosporidium parasites (genotype 1 and genotype 2 of c. parvum, c. muris, and c. serpentis), two eimeria species (e. neischulzi and e. papillata), and giardia duodenalis were used to evaluate the specificity of primers. furthermore, the sensitivity of the genotyping primers was tested by using ... | 1999 | 10508071 |
| in-vitro activity of polycationic peptides against cryptosporidium parvum, pneumocystis carinii and yeast clinical isolates. | the in-vitro activity of magainin ii, indolicidin and ranalexin against 14 clinical isolates of eukaryotic microorganisms was evaluated. antifungal susceptibility testing was performed by broth microdilution, and activity against pneumocystis carinii and cryptosporidium parvum was determined by inoculation on to cell monolayers. for yeasts, peptide mics and mfcs ranged from 6.25 to > 50 mg/l. ranalexin showed the highest activity against candida spp., while magainin ii demonstrated greatest anti ... | 1999 | 10511411 |
| cryptosporidium parvum in oysters from commercial harvesting sites in the chesapeake bay. | oocysts of cryptosporidium parvum, a zoonotic waterborne pathogen, can be removed by bivalve molluscs from contaminated water and retained on gills and in hemolymph. we identified oocysts of c. parvum in oysters from seven sites in the chesapeake bay area. these findings document the presence of c. parvum infectious for humans in oysters intended for human consumption. | 1999 | 10511528 |
| filth flies are transport hosts of cryptosporidium parvum. | 1999 | 10511534 | |
| experimental respiratory cryptosporidiosis in immunosuppressed rats: a light and electron microscopy study. | cryptosporidium parvum is a coccidian protozoon that causes diarrhoeal enteritis in immunocompetent and immunocompromised humans and other mammals. sometimes, chiefly in hiv-infected subjects, anatomical sites other than gastro-intestinal tract, such as the biliary and respiratory tree, are involved. we performed an experimental respiratory infection in immunosuppressed albino rats with a c. parvum human-derived isolate, to confirm the possibility of a primary infection at this site and to evalu ... | 1999 | 10511969 |
| new insights into human cryptosporidiosis. | cryptosporidium parvum is an important cause of diarrhea worldwide. cryptosporidium causes a potentially life-threatening disease in people with aids and contributes significantly to morbidity among children in developing countries. in immunocompetent adults, cryptosporidium is often associated with waterborne outbreaks of acute diarrheal illness. recent studies with human volunteers have indicated that cryptosporidium is highly infectious. diagnosis of infection with this parasite has relied on ... | 1999 | 10515902 |
| characterization of an alpha-tubulin gene of cryptosporidium parvum. | a gene encoding an alpha-tubulin of cryptosporidium parvum was isolated and characterized. it had no introns, and encoded a 441-amino acid protein whose predicted orf represented a typical alpha-tubulin protein with a mw of 50.5 kda. this tubulin had an amino acid sequence similarity with apicomplexa plasmodium falciparum and toxoplasma gondii higher than 88% and shared a number of conserved motifs. | 1999 | 10519222 |
| recent trends in cryptosporidium research: workshop summary. | 1999 | 10519239 | |
| presence of heterogeneous copies of the small subunit rrna gene in cryptosporidium parvum human and marsupial genotypes and cryptosporidium felis. | 1999 | 10519242 | |
| microsatellite analysis of the human and bovine genotypes of cryptosporidium parvum. | 1999 | 10519243 | |
| cryptosporidium parvum: lectins mediate irreversible inhibition of sporozoite infectivity in vitro. | 1999 | 10519244 | |
| identification of a putative telomeric repeat dna binding factor of cryptosporidium parvum. | 1999 | 10519245 | |
| preliminary evidence for a mitochondrion in cryptosporidium parvum: phylogenetic and therapeutic implications. | 1999 | 10519246 | |
| cryptosporidium parvum: synchronized excystation in vitro and evaluation of sporozoite infectivity with a new lectin-based assay. | 1999 | 10519247 | |
| characterization of new monoclonal antibodies against cryptosporidium parvum sporozoites. | 1999 | 10519248 | |
| effects of lactobacillus reuteri on cryptosporidium parvum infection of gnotobiotic tcr-alpha-deficient mice. | 1999 | 10519249 | |
| improved efficacy of dinitroaniline analogs for use as anti-cryptosporidial drugs. | 1999 | 10519250 | |
| changes in murine intestinal epithelium following cryptosporidium parvum infection. | 1999 | 10519251 | |
| change in the phenotypic profiles of spleen and intestinal lymphocytes in dexamethasone-treated mice infected with cryptosporidium parvum. | 1999 | 10519252 | |
| pcr-based quantitation of cryptosporidium parvum in municipal water samples. | a pcr method for the quantitation of cryptosporidium parvum oocysts in municipal drinking water samples was investigated. quantitative pcr uses an internal standard (is) template with unknown target numbers to compare to standards of known concentrations in a standard curve. the is template was amplified using the same primers used to amplify a portion of a 358 bp gene fragment that encodes a repetitive oocyst wall protein in c. parvum. municipal water samples spiked with known numbers of c. par ... | 1999 | 10520592 |
| case-control study of enteropathogens associated with childhood diarrhea in dhaka, bangladesh. | the international centre for diarrhoeal disease research, bangladesh, is a major center for research into diarrheal diseases. the center treats more than 100,000 patients a year. to obtain useful information representative of all patients, a surveillance system in which a 4% systematic sample of all patients is studied in detail, including etiological agents of diarrhea, was installed in october 1979. the first paper on etiology for the surveillance patients was published in 1982, which identifi ... | 1999 | 10523534 |
| survival of cryptosporidium parvum oocysts in source separated human urine. | the survival of cryptosporidium parvum in source separated urine was investigated as part of a broader study on microbial risks associated with the reuse of human urine for sustainable agriculture. a dye permeability assay and in vitro excystation were the primary methods used to assess viability. in the collected urine most of the nitrogen is present as ammonia and the ph is generally around 9. parallel investigations were made in buffers to compare possible toxic effects of urine to actual ph ... | 1999 | 10526401 |
| poor efficacy of residual chlorine disinfectant in drinking water to inactivate waterborne pathogens in distribution systems. | to evaluate the inactivating power of residual chlorine in a distribution system, test microorganisms (escherichia coli, clostridium perfringens, bacteriophage phi-x 170, and poliovirus type 1) were added to drinking water samples obtained from two water treatment plants and their distribution system. except for escherichia coli, microorganisms remained relatively unaffected in water from the distribution systems tested. when sewage was added to the water samples, indigenous thermotolerant colif ... | 1999 | 10528403 |
| reactive nitrogen and oxygen species ameliorate experimental cryptosporidiosis in the neonatal balb/c mouse model. | four-day-old balb/c mice were infected by the oral administration of 50,000 cryptosporidium parvum oocysts, and the resulting infection was scored histologically and by counting colonic oocysts. infection occurred in the ileum and proximal colon (but not duodenum and jejunum), peaked on days 14 to 18, and was cleared between days 24 and 30. nitric oxide (no) appeared to play a protective role in this model as evidenced by the facts that plasma nitrite and nitrate levels increased during the peri ... | 1999 | 10531244 |
| a comparison of the effects of two dinitroanilines against cryptosporidium parvum in vitro and in vivo in neonatal mice and rats. | the effects of two dinitroanilines, oryzalin and trifluralin, were compared against cryptosporidium parvum, in vitro using hct-8 cells and in vivo using neonatal swiss arc mice and wistar neonatal rats. in vitro, oryzalin and trifluralin exhibited ic(50) values (concentration necessary to cause a 50% inhibition) of 750 and 800 nm, respectively. a viability assay showed that neither compound produced a cytotoxic effect on the host cells at concentrations as high as 1 microm. the in vivo component ... | 1999 | 10536296 |
| supplementation with lactobacillus reuteri or l. acidophilus reduced intestinal shedding of cryptosporidium parvum oocysts in immunodeficient c57bl/6 mice. | the effect of l. acidophilus supplementation to reduce fecal shedding of cryptosporidium parvum oocysts was compared to l. reuteri using c57bl/6 female mice immunosuppressed by murine leukemia virus (strain lp-bm5) inoculation. after 12 weeks post lp-bm5 inoculation, 15 immunosuppressed mice each were randomly assinged to one of the following treatment groups: historical control (group a), lp-bm5 control (group b), c. parvum (group c), l. reuteri plus c. parvum (group d) or l. acidophilus plus c ... | 1999 | 10541481 |
| elimination of viruses, phages, bacteria and cryptosporidium by a new generation aquaguard point-of-use water treatment unit. | the elimination of human viruses, phages, bacteria and cryptosporidium oocysts by a new generation commercial aquaguard purifier for the domestic treatment of drinking water, has been evaluated. the unit basically consists of a candle prefilter, activated carbon filter and ultraviolet irradiation compartment. drinking water seeded with selected laboratory test strains of resistant micro-organisms was passed through the unit. similar tests were carried out with sewage-contaminated river water and ... | 1999 | 10546330 |
| cloning and expression of a dna sequence encoding a 41-kilodalton cryptosporidium parvum oocyst wall protein. | this study was conducted to produce a recombinant species-specific oocyst wall protein of cryptosporidium parvum. antigens unique to c. parvum were identified by gradient sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting of oocyst proteins from several different cryptosporidium species. antiserum was then prepared against a 41-kda antigen unique to c. parvum and used to identify a recombinant dna clone, designated rcp41. expression of cp41 mrna in c. parvum oocysts was ... | 1999 | 10548585 |
| does cryptosporidium parvum have a clonal population structure? | cryptosporidiosis, the disease caused in humans by the opportunistic parasite cryptosporidium parvum, is the result of zoonotic or anthroponotic transmission. molecular characterization of different isolates from humans and other mammalian species has recently shown this species to be heterogeneous; this heterogeneity has been linked to the host of isolation, suggesting that the parasites causing zoonotic cryptosporidiosis and those propagated by anthroponotic transmission are genetically distin ... | 1999 | 10557152 |
| a random survey of the cryptosporidium parvum genome. | cryptosporidium parvum is an obligate intracellular pathogen responsible for widespread infections in humans and animals. the inability to obtain purified samples of this organism's various developmental stages has limited the understanding of the biochemical mechanisms important for c. parvum development or host-parasite interaction. to identify c. parvum genes independent of their developmental expression, a random sequence analysis of the 10.4-megabase genome of c. parvum was undertaken. tota ... | 1999 | 10417162 |
| evaluation of quantitative latex agglutination for detection of cryptosporidium parvum, e. coli k99, and rotavirus in calf feces. | a new methodology for detection of rotavirus, escherichia coli k99, and cryptosporidium parvum in bovine fecal samples was developed based on a quantitative latex agglutination technique (qlat). calibrated microspheres coated with specific antibodies to 1 of the enteric pathogens are quantitatively agglutinated by the antigens present in diluted fecal sample. the test is performed in a 96-well flat-bottom plate. the samples were tested with a commercial enzyme-linked immunosorbent assay kit prio ... | 1999 | 10424645 |
| genetic diversity within cryptosporidium parvum and related cryptosporidium species. | to assess the genetic diversity in cryptosporidium parvum, we have sequenced the small subunit (ssu) rrna gene of seven cryptosporidium spp., various isolates of c. parvum from eight hosts, and a cryptosporidium isolate from a desert monitor. phylogenetic analysis of the ssu rrna sequences confirmed the multispecies nature of the genus cryptosporidium, with at least four distinct species (c. parvum, c. baileyi, c. muris, and c. serpentis). other species previously defined by biologic characteris ... | 1999 | 10427023 |
| detection of infectious cryptosporidium parvum oocysts in surface and filter backwash water samples by immunomagnetic separation and integrated cell culture-pcr. | a new strategy for the detection of infectious cryptosporidium parvum oocysts in water samples, which combines immunomagnetic separation (ims) for recovery of oocysts with in vitro cell culturing and pcr (cc-pcr), was field tested with a total of 122 raw source water samples and 121 filter backwash water grab samples obtained from 25 sites in the united states. in addition, samples were processed by percoll-sucrose flotation and oocysts were detected by an immunofluorescence assay (ifa) as a bas ... | 1999 | 10427030 |
| an immunomagnetic separation polymerase chain reaction assay for rapid and ultra-sensitive detection of cryptosporidium parvum in drinking water. | a sensitive and rapid method was developed to detect cryptosporidium parvum oocysts in drinking water. this molecular assay combined immunomagnetic separation with polymerase chain reaction amplification to detect very low levels of c. parvum oocysts. magnetic beads coated with anti-cryptosporidium were used to capture oocysts directly from drinking water membrane filter concentrates, at the same time removing polymerase chain reaction inhibitory substances. the dna was then extracted by the fre ... | 1999 | 10427711 |
| cryptosporidium parvum possesses a short-type replication protein a large subunit that differs from its host. | replication protein a (rpa) consisting of three subunits is a eukaryotic single-stranded dna (ssdna)-binding protein involved in dna replication, repair and recombination. we report here the identification and characterization of a rpa large subunit (cprpa1) gene from the apicomplexan cryptosporidium parvum. the cprpa1 gene encodes a 53.9-kda peptide that is remarkably smaller than that from other eukaryotes (i.e. approximately 70 kda) and is actively expressed in both free sporozoites and paras ... | 1999 | 10427719 |
| characterization of cryptosporidium parvum in human and animal feces by single-tube nested polymerase chain reaction and restriction analysis. | a dna isolation and purification method is described that produced dna free of inhibitory substances in 148 of the 159 analyzed fecal samples. the polymerase chain reaction (pcr) product from a sensitive single-tube nested pcr that amplifies a part of an oocyst protein was used to characterize cryptosporidium parvum genotypes by a simple restriction analysis. genotype 1 was solely detected in human-derived oocysts, genotype 2 was present in both animal and human-derived oocysts. the ratio betwee ... | 1999 | 10431737 |
| improved immunofluorescence assay for detection of giardia and cryptosporidium from asymptomatic adult cervine animals. | we tested an improved immunofluorescence assay (ifa) in detecting giardia and cryptosporidium from feces of asymptomatic adult cervine animals. samples were concentrated by sucrose flotation before being stained by fluorescent monoclonal antibody and examined microscopically. the detection limit was determined as 500 g. intestinalis cysts or 200 c. parvum oocysts/g of sample. among the 82 samples collected from adult fallow deer, columbian black-tailed deer, and tule elk in northern california, ... | 1999 | 10431741 |
| molecular epidemiology of cryptosporidiosis outbreaks and transmission in british columbia, canada. | isolates from 25 (13 sporadic and 12 outbreak) cryptosporidiosis cases, 24 of which were from british columbia, canada, were characterized using nested polymerase chain reaction amplification of the polymorphic internal transcribed spacer 1 locus. two predominant cryptosporidium parvum genotypes were found. twelve (8 sporadic and 4 outbreak) isolates amplified with the cry7/cry21 primer pair and 12 (5 sporadic and 7 outbreak) isolates amplified with the cry7/cryits1 primer pair. multi-locus gene ... | 1999 | 10432058 |
| the efficacy of three common hospital liquid germicides to inactivate cryptosporidium parvum oocysts. | we evaluated three commonly used hospital disinfectants against three concentrations of cryptosporidium parvum oocysts (1.5 x 10(6), 1.5 x 10(5), 1.5 x 10(4)). a 10% phenol product, a 10% povidone-iodine product and a 2.5% glutaraldehyde product were tested against cryptosporidium parvum oocysts without organic load. in-vitro excystation was used to determine viability and a cell culture assay was used to determine infectivity of germicide-treated oocysts. a 2.5% glutaraldehyde product was the m ... | 1999 | 10439996 |
| liver and bile duct pathology following cryptosporidium parvum infection of immunodeficient mice. | patients with acquired immune deficiency syndrome (aids) and boys with mutations of the cd154 gene (causing congenital x-linked immunodeficiency with hyper-igm [xhim]) are susceptible to chronic infections of the biliary tract with cryptosporidium parvum (cp) that may lead to biliary sclerosis and ultimately to cholangiocarcinoma. to determine whether the cp infection and the consequent immune response contribute independently to this morbidity, we infected mice with severe combined immunodefici ... | 1999 | 10385635 |