Search Results

You are looking at 1 - 5 of 5 items for :

  • Author: J. Yang x
Clear All Modify Search
Open access

Y. Wang, J. Guo, S. Qiao, Q. Li, J. Yang, Q. Jin and G. Zhang

Abstract

Porcine reproductive and respiratory syndrome virus (PRRSV) is an important swine pathogen, causing huge economic losses each year worldwide. Immunization with vaccines containing the glycoprotein 5 (GP5) of PRRSV is the main measure to induce neutralizing antibodies and control the disease. Here, we developed a GP5 protein-based ELISA for detecting antibodies against PRRSV. The overall yield of purified GP5 in E. coli flask culture was more than 45 mg/L cell culture. Western blot and IFA indicated that the GP5 protein was highly immunogenic. After optimization and validation with IDEXX PRRS using 566 clinical sera, the DSN, DSP, and accuracy of GP5-ELISA were 81.39%, 75.96%, and 80.39%, respectively. Besides, GP5-ELISA is highly specific, showing no cross-reactions with sera against other important swine pathogens. Hence, GP5 is a good diagnostic antigen and the GP5 protein-based ELISA has the potential to be used in the field.

Open access

Y. Zeng, W. Ye, L. Yang, Y. Huang, K. Zhao, Z. Zhang, H. Liang and J. Kerns

Abstract

Studies were conducted to characterize morphological and molecular profiles of two isolates of Paratrichodorus porosus (SZ1 and SZ2) which were recovered from Acacia mangium in Tianxinshan and Gleichenia linearis in Yangmeikeng environmental monitoring sites in Shenzhen, China, respectively. Analysis of morphometric, morphological and molecular characters revealed these two Shenzhen isolates are identical to P. porosus. Measurements of both study isolates lie within the ranges for P. porosus. It is typologically characterized by possessing a clearly swollen body cuticle after fixation, an onchiostyle ventrally curved, 46–58 μm long, a pharyngeal bulb usually with a well developed anterior-dorsal intestinal overlap, a secretoryexcretory pore opening between the nerve ring and anterior end of pharyngeal bulb, 90–110 μm from the anterior end, a reproductive system with didelphic, amphidelphic, without spermathecae, a pore-like vulva in ventral view and occupying 52.0 %–59.5 % of total body length from anterior end, a short and barrel-shaped vagina with small sclerotizations, a pair of ventromedian advulvar body pores located prevulvar and postvulvar, a rounded tail and a subterminal anus in females. The sequence analysis based on partial rDNA 18S gene and 28S D2/D3 expansion segment confirm its identity as P. porosus. This is the first report of P. porosus associated with A. mangium and G. linearis.

Open access

X. F. Yang, Z. Y. Jiang, Z. M. Tian, Y. Q. Qiu, L. Wang, K. G. Gao, Y. J. Hu and X. Y. Ma

Abstract

The uneven development of adipose tissues reflects a differential occurrence of biological events in vivo while the underlying molecular mechanism remains largely unknown. In the present study, the in vivo inflammatory status of an inbred obese porcine model, Lantang pig, was assessed, aiming to provide evidence for obesity biology. Compared with genetically lean pigs (crossbred, Duroc × Landrace × Large White), Lantang pigs exhibited a larger amount of ultra large adipocytes in subcutaneous adipose tissue accompanied with higher expression of macrophage/monocytes markers and pro-inflammatory genes (TLR4, CD14, CD11β, MCP1, TNFα, IL1β and IL6) and lower expression of cellular antioxidant enzymes (SOD1, 2 and 3). Plasma concentrations of LPS and TNF-α were also higher in Lantang pigs than in lean pigs. Among adipose tissues of Lantang pigs, the subcutaneous tissue had the most abundant expression of inflammation related genes (TLR4, CD14, TNFα and IL6) and the lowest level of cellular antioxidant genes (SOD 1 and 2), while the perirenal adipose tissue had opposite profile. Significant activation of p38 MAPK pathway was indicated by increased phosphorylation of p38 in the subcutaneous adipose tissue of Lantang pigs. Collectively, the bacteria-derived LPS induced inflammation-associated oxidative stress indeed exists in adipose tissues of Lantang pig, and the differential expressions of inflammatory and antioxidant genes, to some extent, account for the uneven development of the adipose tissue within bodies.

Open access

K. Han, D. Zhao, Y. Liu, Q. Liu, X. Huang, J. Yang, K. Bi, T. Xu and Y. Li

Abstract

Duck Tembusu virus (DTMUV) is a newly emerging pathogenic flavivirus that has caused massive economic losses to the duck industry in China. Envelope (E) protein of DTMUV is an important structural protein, which is able to induce protective immune response in target animals and can be used as specific serological diagnosis tool. In this study, a novel monoclonal antibody, designated mAb 3E9, was generated against DTMUV E protein. It is positive in indirect ELISA against both His-E protein and the purified whole viral antigen. Also, this mAb showed positive reaction with DTMUV in Western blot and indirect immunofluorescence assay, and the isotype was IgG1. End-point neutralizing assay performed in BHK-21 cells revealed that the neutralization titer of 3E9 against DTMUV JS804 strain reached 1:50. Furthermore, functional studies revealed that 3E9 blocks infection of DTMUV at a step on viral attachment. The anti-E mAbs produced in the present work may be valuable in developing an antigen-capture ELISA test for antigen detection or a competitive ELISA test for antibody detection or therapeutic medicine for DTMUV in poultry.

Open access

X.F. Yang, J.F. Qin, L. Wang, K.G. Gao, C.T. Zheng, L. Huang and Z.Y. Jiang

Abstract

Glutamine plays an important role in neonatal growth and health. It is unknown whether supplementing the lactating sows’ diet with glutamine will benefit the growth performance and intestinal development of suckling piglets through increasing content of milk glutamine. A total of 24 lactating sows (Large White) were fed diets supplemented with/without 1% glutamine throughout the 21-d lactation. Feed intake of the sows was recorded, blood and milk samples were collected. Piglets were weighed at birth and weaning, one piglet randomly selected from each litter was sacrificed for morphological analysis of the small intestine. Average daily feed intake of the sows did not differ between control and glutamine groups. Concentrations of total protein and urea nitrogen in sows’ serum was increased by glutamine at d 14 of lactation (P<0.05). Contents of glutamine in both plasma and milk of sows were significantly increased by glutamine supplementation throughout lactation (P<0.01). Concentrations of proline, citrulline, valine, isoleucine, leucine, and arginine in sows’ plasma were increased by glutamine supplementation (all P<0.05). Milk yield was increased by glutamine supplementation at d 14 and 21 of lactation (P<0.05). Supplementing the lactating sows’ diet with glutamine increased average daily gain (P=0.006), weaning weight (P=0.032), as well as villous height and ratio of villous height:crypt depth in duodenum of the suckling piglets (both P<0.05). Collectively, supplementing lactating sows’ diet with 1% glutamine significantly improved the growth performance of suckling piglets through elevating milk yield and glutamine content in the milk.