Enrichment of Cryptosporidium parvum from in vitro culture as measured by total RNA and subsequent sequence analysis.

Cryptosporidium parvum is an apicomplexan parasite that infects a wide range of hosts including humans. Due to the parasite's quasi-intracellular, intermembrane location on the host cell, it is difficult to purify parasites from in vitro and in vivo infections for molecular studies. We have developed a method to greatly enrich in vitro C.

Two new species of Eimeria (Apicomplexa: Eimeriidae) from eastern red bats, Lasiurus borealis (Chiroptera: Vespertilionidae), in Arkansas and North Carolina.

During August 2003 and August 2004, 11 adult eastern red bats, Lasiurus borealis, were collected and their feces examined for coccidian parasites. Bats were obtained in August 2003 from Garland, Montgomery, and Yell counties, Arkansas (n=6) and in August 2004 from Anson and Montgomery counties, North Carolina (n=5). Seven (63.

Cryspovirus: a new genus of protozoan viruses in the family Partitiviridae.

The family Partitiviridae includes plant and fungal viruses with bisegmented dsRNA genomes and isometric virions in which the two genome segments are packaged separately and used as templates for semiconservative transcription by the viral polymerase. A new genus, Cryspovirus, has been approved for this family. Its name is based on that of the host genus, Cryptosporidium, which encompasses several species of apicomplexan parasites that infect a wide range of mammals, birds, and reptiles, and are a major cause of human diarrheal illness worldwide.

A New Species of Eimeria (Apicomplexa: Eimeriidae) from the marbled salamander, Ambystoma opacum (Caudata: Ambystomatidae), from northern Louisiana.

Between December 2002 and June 2004, 10 marbled salamanders, Ambystoma opacum, were examined for coccidian parasites. Salamanders were collected in Bradley (n = 2), Little River (n = 1), Miller (n = 1), and Sevier (n = 1) Counties, Arkansas; Webster Parish, Louisiana (n = 2); and Bowie (n = 1) and Nacogdoches (n = 2) Counties, Texas. Two of 10 (20%) A.

Cryptosporidium parvum spermidine/spermine N1-acetyltransferase exhibits different characteristics from the host enzyme.

Cryptosporidosis is a severe opportunistic infection of immuno-compromised individuals for which no reliable therapy exists. The parasite scavenges host-derived polyamines, particularly spermine, which is then converted to the lower polyamines by the combined action of spermidine/spermine N(1)-acetyltransferase (SSAT) and polyamine oxidase (PAO). We have isolated and expressed the Cryptosporidium parvum SSAT for kinetic and molecular comparison with the host enzyme.

Activities of DL-alpha-difluoromethylarginine and polyamine analogues against Cryptosporidium parvum infection in a T-cell receptor alpha-deficient mouse model.

The in vivo effectiveness of a series of conformationally restricted polyamine analogues alone and selected members in combination with DL-alpha-difluoromethylarginine against Cryptosporidium parvum infection in a T-cell receptor alpha-deficient mouse model was tested. Polyamine analogues were selected from the extended bis(ethyl)-sym-homospermidine or bis(ethyl)-spermine backbone having cis or trans double bonds at the center of the molecule. The cis isomers were found to have significantly greater efficacy in both preventing and curing infection in a mouse model than the trans polyamine analogues when tested in a T-cell receptor alpha-deficient mouse model.

Application of quantitative real-time reverse transcription-PCR in assessing drug efficacy against the intracellular pathogen Cryptosporidium parvum in vitro.

We report here on a quantitative real-time reverse transcription-PCR (qRT-PCR) assay for assessing drug efficacy against the intracellular pathogen Cryptosporidium parvum. The qRT-PCR assay detects 18S rRNA transcripts from both parasites, that is, the cycle threshold for 18S rRNA from parasites (C(T)([P18S])) and host cells (C(T)([H18S])), and evaluates the relative expression between parasite and host rRNA levels (i.e.

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.

Irreversible UV inactivation of Cryptosporidium spp. despite the presence of UV repair genes.

Ultraviolet light is being considered as a disinfectant by the water industry because it appears to be very effective for inactivating pathogens, including Cryptosporidium parvum. However, many organisms have mechanisms for repairing ultraviolet light-induced DNA damage, which may limit the utility of this disinfection technology. Inactivation of C.

Cryptosporidium taxonomy: recent advances and implications for public health.

There has been an explosion of descriptions of new species of Cryptosporidium during the last two decades. This has been accompanied by confusion regarding the criteria for species designation, largely because of the lack of distinct morphologic differences and strict host specificity among Cryptosporidium spp. A review of the biologic species concept, the International Code of Zoological Nomenclature (ICZN), and current practices for Cryptosporidium species designation calls for the establishment of guidelines for naming Cryptosporidium species.

Cryptosporidium muris, a rodent pathogen, recovered from a human in Perú.

Cryptosporidium muris, predominantly a rodent species of Cryptosporidium, is not normally considered a human pathogen. Recently, isolated human infections have been reported from Indonesia, Thailand, France, and Kenya. We report the first case of C.

Evaluation of in vitro and in vivo activity of benzindazole-4,9-quinones against Cryptosporidium parvum.

A series of benzindazole-4,9-quinones was tested for growth-inhibitory effects on Cryptosporidium parvum in vitro and in vivo. Most compounds showed considerable activity at concentrations from 25 to 100 micro M. For instance, at 25 micro M the derivatives 5-hydroxy-8-chloro-N1-methylbenz[f]-indazole-4,9-quinone and 5-chloro-N2-methylbenz[f]indazole-4,9-quinone inhibited growth of C.