background: this study was performed to induce conversion of rh strain tachyzoites of toxoplasma gondii to bradyzoites by ph changing of the cul­ture medium. methods: hela cell monolayers were infected at a 1:1 tachyzoite to cell ratio. four hours after infection, the culture medium was removed and re­placed with culture medium and 5% fcs, adjusted to ph 8 with naoh. the culture was maintained ...

background: based on recent studies, there are controversial reports on the ca-pacity of tissue cyst forming of toxoplasma gondii rh strain. in this study, the capac-ity was evaluated by in vivo and in vitro experiments. methods : rh strain was subcutaneously inoculated to ten wistar rats. after one month, their blood, brain, tongue and diaphragm were collected and evaluated by mat, pcr, pathol...

background : toxoplasma gondii is an obligate intracellular parasite that infects humans at high preva-lence rates. the virulent rh strain of t. gondii is generally considered to have lost its cyst forming ca-pacity. this study performed to obtain tissue cysts in mice infected with tachyzoites of rh strain treated with sulfadiazine (sdz). it provides the opportunity to analyze the conversion of...

background: toxoplasma gondii , an apicomplexan parasite, is capable of infecting a broad range of intermediate warm-blooded hosts including humans. the parasite seems to be capable of altering the natural behavior of the host to favor its trans-mission in the environment. the aim of this study was to evaluate the course, alter-ations in behavior along with normal kinetics of the abnormally ind...

background: the aim of this study was to evaluate the effects of conjugated lino-leic acid (cla) on apoptosis of tachyzoites of t . gondii , rh strain (type i) and the cyst-forming tehran strain (type ii) in vitro. methods: toxoplasma strains were injected into the peritoneal cavity of balb/c mice. the tehran strain forms cysts in the brain of mice. bradyzoites within the cysts are reactivated ...

background: serological diagnosis of toxoplasma gondii infection using crude antigens may not be more accurate. to increase the diagnostic potency of anti-gens, isolation of their immunogenic fractions could be useful. the current re-search adopted to obtain an affinity isolated fraction from rh strain using cnbr sepharose 4b column coupled with infected mice sera helping in detec-tion of igm a...

conclusions we found that purified locally isolated soluble crude antigens of the rh strain of t. gondii from the peritoneal cavity of mice may be one of the most promising antigens for detection of human toxoplasmosis in routine screening. results indigenous elisa was used to examine 100 serum samples containing anti-t. gondii igg, with a sensitivity of 98% (commercial kits: 100%). another 100...

BACKGROUND This study was performed to induce conversion of RH strain tachyzoites of Toxoplasma gondii to bradyzoites by pH changing of the culture medium. METHODS HeLa cell monolayers were infected at a 1:1 tachyzoite to cell ratio. Four hours after infection, the culture medium was removed and replaced with culture medium and 5% FCS, adjusted to pH 8 with NaOH. The culture was maintained at...

Toxoplasma gondii is an opportunistic intracellular parasite which induces a highly strong type 1 cytokine response. The present study focuses on defining the factors influencing the outcome of infection with tachyzoites of the type I, highly lethal RH strain, relative to the type II, low virulence strain ME49. Infection with the RH strain led to widespread parasite dissemination and rapid deat...

Thermal inactivation rates were determined for two strains of Bacillus subtilis var. niger spores after equilibration to various relative humidity (RH) levels. In these tests, small thin stainless-steel squares were each inoculated with a drop of spore suspension and equilibrated to 11, 33, or 85% RH. Following equilibration, the squares were placed on a hot plate preheated to 108, 125, 136, 16...