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Mohhammed ASADPOUR Gholamreza RAZMI Gholamreza MOHHAMMADI Abolghasen NAGHIBI 《Iranian Journal of Parasitology》2013,8(4):601-607
Background
Cryptosporidium parvum is a zoonotic pathogen transmissible from a variety of animals to humans and is a considerable public health concern. Dairy cattle have been identified in numerous reports as a major source of environmental contamination with this pathogen. The aim of study was to detect and isolate the Cryptosporidium spp. from fecal samples of naturally infected pre-wean calves in the Mashhad areaMethods
Overall, 300 fecal specimens from 1 to 30 days pre-weaned calves were collected from 10 farms in the Mashhad area the capital center of the Khorasan Razavi Province, Iran and microscopically examined for Cryptosporidium spp. All infected samples were also analyzed using nested –PCR. A polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the small-subunit (SSU) rRNA gene was also used to detect and identify Cryptosporidium spp. in PCR- positive samples.Results
Eighty five (28.3%) of the specimens were positive for Cryptosporidium spp. The prevalence of Cryptosporidium spp. in 8-14 days old and diarrheic calves were significantly higher than other groups. Restriction digestion of the PCR products by SspI, VspI restriction enzymes and sequence analysis revealed the presence of C. parvum bovine genotype in all isolates.Conclusions
Our results suggest that pre-weaned calves are likely to be an important reservoir of zoonotic C. parvum. 相似文献2.
Ayman EM Mahdy Joseph C Cheng Jun Li Saeed Elojeimy William D Meacham Lorianne S Turner Aiping Bai Christopher R Gault Alex S McPherson Nicole Garcia Thomas H Beckham Antonio Saad Alicja Bielawska Jacek Bielawski Yusuf A Hannun Thomas E Keane Mohhammed I Taha Hisham M Hammouda James S Norris Xiang Liu 《Molecular therapy》2009,17(3):430-438
Radiation resistance in a subset of prostate tumors remains a challenge to prostate cancer radiotherapy. The current study on the effects of radiation on prostate cancer cells reveals that radiation programs an unpredicted resistance mechanism by upregulating acid ceramidase (AC). Irradiated cells demonstrated limited changes of ceramide levels while elevating levels of sphingosine and sphingosine-1-phosphate. By genetically downregulating AC with small interfering RNA (siRNA), we observed radiosensitization of cells using clonogenic and cytotoxicity assays. Conversely, AC overexpression further decreased sensitivity to radiation. We also observed that radiation-induced AC upregulation was sufficient to create cross-resistance to chemotherapy as demonstrated by decreased sensitivity to Taxol and C6 ceramide compared to controls. Lower levels of caspase 3/7 activity were detected in cells pretreated with radiation, also indicating increased resistance. Finally, utilization of the small molecule AC inhibitor, LCL385, sensitized PPC-1 cells to radiation and significantly decreased tumor xenograft growth. These data suggest a new mechanism of cancer cell resistance to radiation, through upregulation of AC that is, in part, mediated by application of the therapy itself. An improved understanding of radiotherapy and the application of combination therapy achieved in this study offer new opportunities for the modulation of radiation effects in the treatment of cancer. 相似文献
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