Cryptosporidium spp., Giardia intestinalis, and Enterocytozoon bieneusi in Captive Non-Human Primates in Qinling Mountains.

Non-human primates (NHPs) are confirmed as reservoirs of Cryptosporidium spp., Giardia intestinalis, and Enterocytozoon bieneusi. In this study, 197 fresh fecal samples from 8 NHP species in Qinling Mountains, northwestern China, were collected and examined using multilocus sequence typing (MLST) method. The results showed that 35 (17.8%) samples were positive for tested parasites, including Cryptosporidium spp. (3.0%), G. intestinalis (2.0%), and E. bieneusi (12.7%). Cryptosporidium spp. were detected in 6 fecal samples of Macaca mulatta, and were identified as C. parvum (n=1) and C. andersoni (n=5). Subtyping analysis showed Cryptosporidium spp. belonged to the C. andersoni MLST subtype (A4, A4, A4, and A1) and C. parvum 60 kDa glycoprotein (gp60) subtype IId A15G2R1. G. intestinalis assemblage E was detected in 3 M. mulatta and 1 Saimiri sciureus. Intra-variations were observed at the triose phosphate isomerase (tpi), beta giardin (bg), and glutamate dehydrogenase (gdh) loci, with 3, 1, and 2 new subtypes found in respective locus. E. bieneusi was found in Cercopithecus neglectus (25.0%), Papio hamadrayas (16.7%), M. mulatta (16.3%), S. sciureus (10%), and Rhinopithecus roxellana (9.5%), with 5 ribosomal internal transcribed spacer (ITS) genotypes: 2 known genotypes (D and BEB6) and 3 novel genotypes (MH, XH, and BSH). These findings indicated the presence of zoonotic potential of Cryptosporidium spp. and E. bieneusi in NHPs in Qinling Mountains. This is the first report of C. andersoni in NHPs. The present study provided basic information for control of cryptosporidiosis, giardiasis, and microsporidiosis in human and animals in this area.

Classical swine fever virus induces oxidative stress in swine umbilical vein endothelial cells.

BACKGROUND: Classical swine fever virus (CSFV) infection causes significant losses of pigs, which is characterized by hemorrhage, disseminated intravascular coagulation and leucopenia. The swine vascular endothelial cell is a primary target cell for CSFV. The aim of this study was to determine the role of CSFV infection in inducing oxidative stress (OS) in vascular endothelial cells. RESULTS: We demonstrated that CSFV infection induced oxidative stress in swine umbilical vein endothelial cells (SUVECs), characterized by the induction of reactive oxygen species (ROS) production and the elevations of porcine antioxidant proteins thioredoxin (Trx), peroxiredoxin-6 (PRDX-6) and heme oxygenase-1 (HO-1) expression. Furthermore, cyclooxygenase-2 (COX-2), a pro-inflammatory protein related to oxidative stress, was up-regulated while anti-inflammatory protein peroxisome proliferator-activated receptor-γ (PPAR-γ), an important mediator in vascular functional regulation, was down-regulated in the CSFV infected cells. In addition, antioxidants showed significant inhibitory effects on the CSFV replication, indicating a close relationship between CSFV replication and OS induced in the host cells. CONCLUSIONS: Our results indicated that CSFV infection induced oxidative stress in SUVECs. These findings provide novel information on the mechanism by which CSFV can alter intracellular events associated with the viral infection.

Determining geographical variations in Ascaris suum isolated from different regions in northwest China through sequences of three mitochondrial genes.

The sequence diversities in three mitochondrial DNA (mtDNA) regions, namely portions of NADH dehydrogenase subunit 1 (pnad1), cytochrome c oxidase subunit 1 (pcox1), and NADH dehydrogenase subunit 4 (pnad4), were investigated in all Ascaris suum samples isolated from four regions in northwestern China. Those genes were amplified by PCR method and the lengths of pnad1, pcox1, and pnad4 were 419 bp, 711 bp, and 723 bp, respectively. The intraspecific sequence variations within A. suum samples were 0-2.9% for pnad1, 0-2.1% for pcox1, and 0-3.1% for pnad4. Phylogenetic analysis combined with three sequences of mtDNA fragments showed that all A. suum samples were monophyletic groups, but samples from the same geographical origin did not always cluster together. The results suggested that the three mtDNA fragments could not be used as molecular markers to identify the A. suum isolates from four regions, and have important implications for studying molecular epidemiology and population genetics of A. suum.

Molecular identification of Pomacea canaliculata and P. insularum from rice paddy in different origins in China using mitochondrial adenosine triphosphate subunit 6 gene.

To identify Pomacea canaliculata and P. insularum using a molecular approach, the partial sequences of mitochondrial (mt) adenosine triphosphate subunit 6 (patp6) genes of two apple snails species from eight provinces of China were obtained. The intra-specific variations in mt patp6 within P. canaliculata were 0-4.5%, and no sequence difference in this region was observed within P. insularum. However, high inter-specific variations between P. canaliculata and P. insularum were detected, with sequence differences of 8.9-10.1%. Phylogenetic analyses based on sequences of mt patp6 revealed that P. canaliculata and P. insularum were grouped in different clades, but the genetic trees could not reveal geographically genetic relationships of P. canaliculata isolates from different origins. These findings will provide basic information for further study of molecular epidemiology and control of Pomacea invasion in China as well as in the world.

Genetic variability of Baylisascaris schroederi from the Qinling subspecies of the giant panda in China revealed by sequences of three mitochondrial genes.

The present study examined the variations in three mitochondrial (mt) DNA sequences, namely cytochrome b (cytb), cytochrome c oxidase subunit 3 (cox3) and NADH dehydrogenase subunit 5 (nad5), among Baylisascaris schroederi isolates from the Qinling subspecies of the giant panda in Shaanxi province, northwestern China. No differences in length were detected in the three mt fragments from different isolates. The intra-specific sequence variations within all B. schroederi samples were 0-2.6% for pcytb, 0-1.8% for pcox3 and 0-2.1% for pnad5, while the inter-specific sequence differences among members of the genus Baylisascaris were 8.2-15.2%, 6.2-15.9% and 8.4-16.0% for pcytb, pcox3, pnad5, respectively. A phylogenetic analysis of the combined sequences of pcytb, pcox3 and pnad 5 showed that all B. schroederi samples in the present study were located in two large clusters, with one cluster containing samples from giant pandas in Sichuan province. These findings provide basic information for further study of molecular epidemiology and control of B. schroederi infection in the Qinling subspecies of the giant panda and throughout China.

The expression dynamics of IL-17 and Th17 response relative cytokines in the trachea and spleen of chickens after infection with Cryptosporidium baileyi.

BACKGROUND: Cryptosporidium baileyi is the dominant Cryptosporidium species in birds causing emerging health problems in the poultry industry, and is also a model to study the biology of Cryptosporidium spp.. IL-17 (also called IL-17A) is a hallmark pro-inflammatory cytokine of Th17 cells that plays an important role in several human autoimmune diseases and microbial infection disease of many animals, and it may play a role in Cryptosporidium infection. METHODS: The present study examined the mRNA level of IL-17 and Th17 response relative cytokines in the trachea and spleen of C. baileyi-infected chickens at different time points using real-time quantitative PCR (qPCR). RESULTS: All examined cytokines in the trachea were up-regulated in the infected chickens compared with the uninfected control during C. baileyi infection. Significant increased IL-17 mRNA level in the trachea was observed as early as 12 h post infection (pi), peaking at 24 h pi and 10 d pi, and declining thereafter. The transcription levels of IL-17 and Th17 response relative cytokines in spleen were also significantly increased at different time points during the infection. CONCLUSIONS: IL-17 was indicated to participate in the induction of inflammation during infection of some intracellular protozoan parasites. The results in the present study suggest that IL-17 may play a role in immunity against Cryptosporidium infection, and provide basic information for determining the role of Th17 cell in Cryptosporidium infection.

Genetic variability among Dicrocoelium dendriticum isolates from different regions in Shaanxi Province, China revealed by sequences of three mitochondrial genes.

The genetic variations in three mitochondrial DNA (mtDNA) regions, namely portion of cytochrome c oxidase subunit 1 (pcox1), NADH dehydrogenase subunit 1 (pnad1) and cytochrome b (pcytb), were examined for Dicrocoelium dendriticum samples isolated from different origins in Shaanxi Province, northwestern China. The intra-specific sequence differences within D. dendriticum samples were 0-0.52% for pcox1, 0-0.73% for pnad1 and 0-0.58% for pcytb. Phylogenetic analyses based on combined sequences of three mtDNA showed that all D. dendriticum samples were clustered together in same clade of Paragonimus westermani. But the phylogenetic trees could not reveal geographically genetic relationships of D. dendriticum isolates in this province. These findings will provide basic information for further study of molecular epidemiology and control of D. dendriticum infection in this province as well as in China.