objective :cryptosporidiosis is one of the most important parasitic infections in iran which causes diarrhea in humans and animals. the identification of the cryptosporidium species among humans is necessary. this study aims to identify species of cryptosporidium isolated from patients that referred to three hospitals in tehran based on the 18s rrna gene by nested pcr-rflp assay. ‎methods :in t...

We have examined the time course and patterns of covalent aflatoxin B1:DNA adducts produced within the ribosomal RNA gene sequences isolated from the liver nuclear DNA of aflatoxin B1-treated animals. Liver nuclear DNA was initially enriched in ribosomal DNA by cesium salt density centrifugation, and incubated under alkaline conditions to stabilize bound aflatoxin B1-DNA moieties. Alkali-treate...

background: clarithromycin resistance in helicbacter pylori has been found to be associated with point mutations in 23s rrna gene leads to reduced affinity of the antibiotic to its ribosomal target or changing the site of methylation. the aim of this study was to determine the most important point mutations in 23s rrna gene in h. pylori that are closely related to clarith-romycin resistance amo...

introduction: helicobacter pylori (h. pylori), is a bacterium responsible for upper gastrointestinal tract diseases. the 16s rrna is a common h. pylori gene which are usually preferred for diagnosis purpose. the aim of this study was to determine the prevalence and abundance of 16s rrna in fecal samples and also evaluate correlation between the level of 16s rrna and activities of the cytokines,...

background: there is a conserved portion in the 16s rrna gene of bacteria which can be amplified by the universal pcr method. this fragment is 996 bp in length. in this method, only one set of universal primers is used for the amplification of the conserved region of the 16s rrna gene, in common bacterial pathogens. therefore, using the universal pcr method, these bacteria are detectable only b...

background: bovine theileriosis results from infection with obligate intracellular protozoa of the genus theileria . the phylogenetic relationships between two isolates of theileria annulata , and 36 theile­ria spp . , as well as 6 outgroup including babesia spp . and coccidian protozoa were analyzed using the 18s rrna gene sequence. methods: the target dna segment was amplified by pcr. the pcr...

We report the identification of a new gene, RRP3 (rRNA processing), which is required for pre-rRNA processing. Rrp3 is a 60.9 kDa protein that is required for maturation of the 35S primary transcript of pre-rRNA and is required for cleavages leading to mature 18S RNA. RRP3 was identified in a PCR screen for DEAD box genes. DEAD box genes are part of a large family of proteins homologous to the ...

Background: Theileria spp. were targeted for detection and differentiation from clinical samples using PCR in the current investigation diagnostic sensitivity of this method was evaluated comparison to microscopic observations. The characteristics bovine tropical theileriosis as markers also analysed based on data. Methods: On basis evaluation inspection blood smears, 200 cattle suspected havin...

background and objectives: anaplasma phagocytophilum is a zoonotic, tick borne rickettsial pathogen. a. phagocytophilum has been detected in north america, europe, africa and asia by molecular methods. in iran we have little information about the distribution of this agent in human and animals. materials and methods: from march 2007 to july 2007, one hundred and fifty blood samples and correspo...