Aiqin Liu

Publications (9)30.01 Total impact

• Source

  Available from: Longxian Zhang

  Article: Distribution and Genetic Characterizations of Cryptosporidium spp. in Pre-Weaned Dairy Calves in Northeastern China's Heilongjiang Province.

  Weizhe Zhang, Rongjun Wang, Fengkun Yang, Longxian Zhang, Jianping Cao, Xiaoli Zhang, Hong Ling, Aiqin Liu, Yujuan Shen
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  ABSTRACT: BACKGROUND: Cryptosporidium spp. are common parasites of humans and animals. Farm animals, especially pre-weaned calves, are considered to be one of main animal reservoir hosts of Cryptosporidium in the transmission of human cryptosporidiosis. The aim of this study was to determine the distribution and genotypes of Cryptosporidium spp. in pre-weaned calves using molecular tools and to assess zoonotic transmission and elucidate the public health significance in northeastern China. METHODOLOGY/PRINCIPAL FINDINGS: A total of 151 fecal specimens from pre-weaned calves were collected in Heilongjiang Province and were screened for Cryptosporidium by PCR. The average prevalence of Cryptosporidium was 47.68% (72/151). Cryptosporidium spp. were characterized by DNA sequencing of the small subunit (SSU) rRNA gene and the 60-kDa glycoprotein (gp60) gene. Based on the SSU rRNA gene, five Cryptosporidium spp. were identified, including C. bovis (n = 34), C. andersoni (n = 26), C. ryanae (n = 5), C. meleagridis (n = 5) and C. parvum (n = 2). The SSU rRNA nucleotide sequences were identical to each other, respectively, within C. ryanae, C. parvum, C. meleagridis and C. andersoni. Four types of C. bovis were found in the SSU rRNA gene, with two novel types. The gp60 gene was successfully sequenced in one C. parvum isolate and three C. meleagridis isolates, with IIdA19G1 for C. parvum and IIIeA22G2R1 for C. meleagridis. CONCLUSION/SIGNIFICANCE: Molecular analysis indicates that Cryptosporidium spp. are endemic in pre-weaned calves in Heilongjiang Province. The findings of C. parvum and C. meleagridis suggested the possibility of zoonotic transmission and public health significance. The transmission dynamics of C. parvum and C. meleagridis needed to be clarified by further molecular epidemiologic studies from humans and animals. Whether calves could act as the natural reservoirs of C. meleagridis needed to be confirmed by more systematic experimental infection studies.
  PLoS ONE 01/2013; 8(1):e54857. · 4.09 Impact Factor
• Article: Genetic Characterizations of Giardia duodenalis in Sheep and Goats in Heilongjiang Province, China and Possibility of Zoonotic Transmission.

  Weizhe Zhang, Xiaoli Zhang, Rongjun Wang, Aiqin Liu, Yujuan Shen, Hong Ling, Jianping Cao, Fengkun Yang, Xiaoyun Zhang, Longxian Zhang
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  ABSTRACT: Giardia duodenalis is a widespread intestinal protozoan of both humans and mammals. To date, few epidemiological studies have assessed the potential and importance of zoonotic transmission; and the human giardiasis burden attributable to G. duodenalis of animal origin is unclear. No information about occurrence and genotyping data of sheep and goat giardiasis is available in China. The aim of the present study was to determine prevalence and distribution of G. duodenalis in sheep and goats in Heilongjiang Province, China, and to characterize G. duodenalis isolates and assess the possibility of zoonotic transmission. A total of 678 fecal specimens were collected from sheep and goats on six farms ranging in age from one month to four years in Heilongjiang Province, China. The average prevalence of G. duodenalis infection was 5.0% (34/678) by microscopy after Lugol's iodine staining, with 5.6% (30/539) for the sheep versus 2.9% (4/139) for the goats. Molecular analysis was conducted on 34 G. duodenalis isolates based on the triosephosphate isomerase (tpi) gene. 29 tpi gene sequences were successfully obtained and identified as assemblages A (n = 4), B (n = 2) and E (n = 23). High heterogeneity was observed within assemblage E at the tpi locus, with five novel subtypes found out of seven subtypes. Two subtypes of assemblage A were detected, including subtype AI (n = 3) and a novel subtype (designated as subtype AIV) (n = 1). Two assemblage B isolates were identical to each other in the tpi gene sequences. This is the first report of G. duodenalis infections in sheep and goats in China. The present data revealed the unique endemicity on prevalence, distribution and genetic characterization of G. duodenalis in sheep and goats in Heilongjiang Province. The findings of assemblages A and B in sheep and goats implied the potential of zoonotic transmission.
  PLoS Neglected Tropical Diseases 09/2012; 6(9):e1826. · 4.69 Impact Factor
• Article: Occurrence of bovine giardiasis and endemic genetic characterization of Giardia duodenalis isolates in Heilongjiang Province, in the Northeast of China.

  Aiqin Liu, Xiaoyun Zhang, Longxian Zhang, Rongjun Wang, Xingchao Li, Jing Shu, Xiaoli Zhang, Yujuan Shen, Weizhe Zhang, Hong Ling
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  ABSTRACT: To determine the prevalence of bovine giardiasis in Heilongjiang Province in China and to molecularly characterize Giardia duodenalis, feces were collected from 814 dairy and beef cattle ranging in age from 6 days to 9 years. Clinical symptoms of diarrhea were recorded at the time of sampling. The G. duodenalis infection rate in cattle was 5.2 % (42/814) as determined by Lugol's iodine staining. G. duodenalis assemblages and subtypes were genetically diagnosed by sequence analysis of the triosephosphate isomerase (TPI) gene. Three assemblages were identified, representing A (n = 1), B (n = 18), and E (n = 24), with a mixed infection case of assemblages A and E. High heterogeneity was also observed within assemblages B and E at the TPI locus. Among the assemblages, eight subtypes of assemblage B and three subtypes of assemblage E were found to be novel subtypes. Findings on assemblages A and B are of public health importance. The zoonotic potential of bovine giardiasis needs to be further assessed by extensive genetic data of assemblages A and B from humans at the subtype level. The newly found subtypes of assemblages B and E imply that the evaluation of geographically distributed subtypes is of importance.
  Parasitology Research 03/2012; 111(2):655-61. · 2.15 Impact Factor
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  Available from: dx.plos.org

  Article: Multilocus sequence subtyping and genetic structure of Cryptosporidium muris and Cryptosporidium andersoni.

  Rongjun Wang, Fuchun Jian, Longxian Zhang, Changshen Ning, Aiqin Liu, Jinfeng Zhao, Yaoyu Feng, Meng Qi, Helei Wang, Chaochao Lv, Guanghui Zhao, Lihua Xiao
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  ABSTRACT: In this study, nine C. muris and 43 C. andersoni isolates from various animals in China were subtyped by a multilocus sequence typing (MLST) tool. DNA sequence analyses showed the presence of 1-2 subtypes of C. muris and 2-6 subtypes of C. andersoni at each of the four loci (MS1, MS2, MS3, and MS16), nine of which represented new subtypes. Altogether, two C. muris and 10 C. andersoni MLST subtypes were detected. Linkage disequilibrium analysis indicated although the overall population structure of the two parasites was clonal, the Chinese C. andersoni in cattle has an epidemic structure. Three and two clusters were produced in the C. muris and C. andersoni populations by Structure 2.3.3 analysis, with Chinese C. muris and C. andersoni substructures differing from other countries. Thus, this study suggested the prevalence of C. andersoni in China is not attributed to the introduction of dairy cattle. More studies involving more genetic loci and systematic sampling are needed to better elucidate the population genetic structure of C. muris and C. andersoni in the world and the genetic basis for the difference in host specificity among the two most common gastric parasites.
  PLoS ONE 01/2012; 7(8):e43782. · 4.09 Impact Factor
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  Available from: Longxian Zhang

  Article: Cryptosporidium cuniculus and Giardia duodenalis in rabbits: genetic diversity and possible zoonotic transmission.

  Weizhe Zhang, Yujuan Shen, Rongjun Wang, Aiqin Liu, Hong Ling, Yihong Li, Jianping Cao, Xiaoyun Zhang, Jing Shu, Longxian Zhang
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  ABSTRACT: Cryptosporidium and Giardia are the two important zoonotic pathogens causing diarrhea of humans and animals worldwide. Considering the human cryptosporidiosis outbreak and sporadic cases caused by C. cuniculus, the important public health significance of G. duodenalis and little obtained information regarding rabbit infected with Cryptosporidium and Giardia in China, the aim of this study is to determine the prevalence and molecularly characterize Cryptosporidium and Giardia in rabbits in Heilongjiang Province, China. 378 fecal samples were obtained from rabbits in Heilongjiang Province. Cryptosporidium oocysts and Giardia cysts were detected using Sheather's sugar flotation technique and Lugol's iodine stain method, respectively. The infection rates of Cryptosporidium and Giardia were 2.38% (9/378) and 7.41% (28/378), respectively. Genotyping of Cryptosporidium spp. was done by DNA sequencing of the small subunit rRNA (SSU rRNA) gene and all the nine isolates were identified as Cryptosporidium cuniculus. The nine isolates were further subtyped using the 60-kDa glycoprotein (gp60) gene and two subtypes were detected, including VbA32 (n = 3) and a new subtype VbA21 (n = 6). G. duodenalis genotypes and subtypes were identified by sequence analysis of the triosephosphate isomerase (TPI) gene. The assemblage B (belonging to eight different subtypes B-I to B-VIII) was found in 28 G. duodenalis-positive samples. The rabbits have been infected with Cryptosporidium and Giardia in Heilongjiang Province. The results show that the rabbits pose a threat to human health in the studied areas. Genotypes and subgenotypes of C. cuniculus and G. duodenalis in this study might present the endemic genetic characterization of population structure of the two parasites.
  PLoS ONE 01/2012; 7(2):e31262. · 4.09 Impact Factor
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  Available from: Lihua Xiao

  Article: Molecular identification and distribution of Cryptosporidium and Giardia duodenalis in raw urban wastewater in Harbin, China.

  Aiqin Liu, Hong Ji, Ensheng Wang, Jingbo Liu, Lihua Xiao, Yujuan Shen, Yihong Li, Weizhe Zhang, Hong Ling
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  ABSTRACT: Contamination of the water supply by protozoa often causes outbreaks of cryptosporidiosis and giardiasis. The goals of the present study was to investigate the level of Cryptosporidium and Giardia duodenalis in wastewater from wastewater treatment plants in Harbin, China, and to understand the endemic transmission characteristics of cryptosporidiosis and giardiasis. Forty-eight domestic wastewater specimens from the two wastewater treatment plants in Harbin City were collected from April 2009 to March 2010. Cryptosporidium spp. and G. duodenalis assemblages were identified by PCR and sequencing of the 18S ribosomal RNA and the triosephosphate isomerase genes, respectively. In total, 15 wastewater specimens were PCR positive for Cryptosporidium and 23 were PCR positive for G. duodenalis. The prevalence of contamination with G. duodenalis (47.9%) was higher than that of Cryptosporidium (31.3%). Molecular identification showed the presence of two Cryptosporidium spp. (14 belonging to Cryptosporidium andersoni and one belonging to Cryptosporidium ubiquitum) and two G. duodenalis assemblages (18 belonging to assemblage AII and six belonging to assemblage B). In addition, eight specimens contained both Cryptosporidium and G. duodenalis, and one specimen contained G. duodenalis assemblages AII and B. These results suggested humans might be the primary source of G. duodenalis contamination in wastewater in the studied area. In contrast, a low prevalence of C. ubiquitum suggested a reduced risk of human cryptosporidiosis caused by C. ubiquitum via waterborne route. This work provides basic experimental data needed for local wastewater treatment plants to develop protective strategies for water safety and to eliminate waterborne parasites.
  Parasitology Research 04/2011; 109(3):913-8. · 2.15 Impact Factor
• Article: Prevalence and distribution of Cryptosporidium spp. in dairy cattle in Heilongjiang Province, China.

  Aiqin Liu, Rongjun Wang, Yihong Li, Longxian Zhang, Jing Shu, Weizhe Zhang, Yaoyu Feng, Lihua Xiao, Hong Ling
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  ABSTRACT: Few data are available on the molecular characterization of Cryptosporidium spp. in cattle in China. In the present study, a total of 507 fecal specimens from six dairy farms in Heilongjiang Province were examined for Cryptosporidium spp. by light microscopy of concentrates from the formalin-ethyl acetate sedimentation method (for less than 2-month-old calves) or Sheather's floatation method (more than 3-month-old dairy cattle). Twenty-seven post-weaned calves on five farms were positive for Cryptosporidium oocysts. PCR and DNA sequence analysis of the 18S rRNA, actin, and 70 kDa heat shock protein genes identified Cryptosporidium andersoni and Cryptosporidium ryanae, with C. andersoni as the dominant species (26 out of 27). In comparison with other regions of the world, the distribution of Cryptosporidium species in the areas appears to be unique.
  Parasitology Research 06/2009; 105(3):797-802. · 2.15 Impact Factor
• Article: UHMWPE carrying estradiol to treat the particle-induced osteolysis-Processing and characterizing.

  Aiqin Liu, Shuxin Qu, Mengmeng Chao, Minhao Zhu, Jie Weng, Zhongrong Zhou
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  ABSTRACT: The objective of this study was to explore the possibility of UHMWPE implant used as the drug carrier to treat particle-induced osteolysis. 17beta-estradiol (E2), which had the potential application on osteolysis treatment and the high melting point, was added into UHMWPE powder to produce UHMWPE-E2 composites through hot press processing. The hydrophobicity, crystallinity, mechanical properties, and wear performance of the UHMWPE-E2 were characterized compared with the control UHMWPE. The thermal analysis and Fourier Transform Infrared Spectroscopy results demonstrated that the hot press processing would not alter the functional groups of E2 in this study. There were no significant differences in the hydrophobicity and crystallinity between the UHMWPE-E2 and UHMWPE. The UHMWPE-E2 showed satisfying mechanical properties, including ultimate tensile strength (47.2 +/- 3.6 MPa), yield strength (25.0 +/- 0.6 MPa) and elongation at break (320 +/- 25.5 %), which were similar with the control UHMWPE. The friction coefficients and worn scars were similar between the UHMWPE-E2 and the control UHMWPE. The wear mechanism of the UHMWPE-E2 and UHMWPE both were abrasive wear under dry friction. The UHMWPE-E2 possesses the approving mechanical properties and wear performance compared with the control UHMWPE, which might be used as the potential implanted drug carrier to prevent the particle-induced osteolysis in joint replacements.
  Journal of Biomedical Materials Research Part A 07/2008; 90(2):496-505. · 2.63 Impact Factor
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  Available from: beyotime.com

  Article: Expression and localization of transcription factor Ets-1 in the rat ovary during the estrous cycle and pregnancy.

  Xiaohui Xiao, Aiqin Liu, Haixia Wen, Yanjun Tian, Jiang Ni, Guoyi Liu
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  ABSTRACT: To examine the expression and localization of Ets-1 in the rat ovary during the estrous cycle and pregnancy, and to investigate its effects on ovarian function. Prospective, randomized study. Department of Physiology at Harbin Medical University. Pubertal female Wistar rats. Vaginal smears were taken daily from female rats to determine the stage of the estrous cycle. Pregnancies were achieved by caging female and male rats together overnight. Ovaries were collected from both cycling and pregnant rats for tissue sectioning and RNA and protein extractions. Real-time quantitative polymerase chain reaction, Western blot, in situ hybridization, and immunohistochemistry were performed to investigate the expression and localization of Ets-1 messenger RNA (mRNA) and protein in the rat ovary during the estrous cycle and pregnancy. During the estrous cycle, the levels of Ets-1 mRNA and protein expression increased during the follicular phase, achieving their highest measurements at proestrus and lowest at metestrus. The expression of Ets-1 mRNA and protein fluctuated during pregnancy, increasing during early pregnancy, then decreasing during mid-pregnancy, and again increasing until parturition. Ets-1 mRNA and protein were present throughout the estrous cycle and pregnancy, principally localized in follicles of various sizes and in the corpus luteum. Ets-1 may participate and play an important role in the regulation of follicular development, corpus luteum formation, maintenance, and regression.
  Fertility and sterility 05/2008; 91(5 Suppl):1998-2005. · 3.97 Impact Factor