Annexin A2 gene interacting with viral matrix protein to promote bovine ephemeral fever virus release

Bovine ephemeral fever virus (BEFV) causes bovine ephemeral fever, which can produce considerable economic damage to the cattle industry. However, there is limited experimental evidence regarding the underlying mechanisms of BEFV. Annexin A2 (AnxA2) is a calcium and lipid-conjugated protein that binds phospholipids and the cytoskeleton in a Ca 2+ -dependent manner, and it participates in various cellular functions, including vesicular trafficking, organization of membrane domains, and virus proliferation. The role of the AnxA2 gene during virus infection has not yet been reported. In this study, we observed that AnxA2 gene expression was up-regulated in BHK-21 cells infected with the virus.Additionally, overexpression of the AnxA2 gene promoted the release of mature virus particles, whereas BEFV replication was remarkably inhibited after reducing AnxA2 gene expression by using the small interfering RNA (siRNA). For viral proteins, overexpression of the Matrix (M) gene promotes the release of mature virus particles. Moreover, the AnxA2 protein interaction with the M protein of BEFV was confirmed by GST pull-down and coimmunoprecipitation assays. Experimental results indicate that the C-terminal domain (268– 334 aa) of AxnA2 contributes to this interaction. An additional mechanistic study showed that AnxA2 protein interacts with M protein and mediates the localization of the M protein at the plasma membrane. Furthermore, the absence of the AnxA2-V domain could attenuate the effect of AnxA2 on BEFV replication. These findings can contribute to elucidating the regulation of BEFV replication and may have implications for antiviral strategy development.

Rapid visual detection of Mycobacterium avium subsp. paratuberculosis by recombinase polymerase amplification combined with a lateral flow dipstick

Paratuberculosis (Johne's disease) is a chronic debilitating disease of domestic and wild ruminants. However, widespread point-of-care testing is infrequent due to the lack of a robust method. The isothermal recombinase polymerase amplification (RPA) technique has applied for rapid diagnosis. Herein, RPA combined with a lateral flow dipstick (LFD) assay was developed to estimate DNA from Mycobacterium avium subsp. paratuberculosis. First, analytical specificity and sensitivity of the RPA-nfo primer and probe sets were assessed. The assay successfully detected M. paratuberculosis DNA in 30 min at 39℃ with a detection limit of up to eight copies per reaction, which was equivalent to that of the real-time quantitative polymerase chain reaction (qPCR) assay. The assay was specific, as it did not amplify genomes from five other Mycobacterium spp. or five pathogenic enteric bacteria. Six hundred-twelve clinical samples (320 fecal and 292 serum) were assessed by RPA-LFD, qPCR, and enzyme-linked immunosorbent assay, respectively. The RPA-LFD assay yielded 100% sensitivity, 97.63% specificity, and 98.44% concordance rate with the qPCR results. This is the first report utilizing an RPA-LFD assay to visualize and rapidly detect M. paratuberculosis. Our results show this assay should be a useful method for the diagnosis of paratuberculosis in resource-constrained settings.

Research progress in corneal neovascularization and microenvironment / 中华实验眼科杂志

In a variety of pathological conditions,capillaries grow from corneal limbus to the central cornea area,to form corneal neovascularization (CNV).CNV destroys the normal corneal microenvironment, reduces the transparency of cornea, seriously affects visual acuity and leads to corneal transplantation immune rejection.Corneal microenvironment includes inflammatory mediators, cytokines and extracellular matrix (ECM).Studies showed that corneal microenvironment changes have a close relationship with CNV.This article reviewed the relationship of corneal microenvironment with CNV.

Application of the modulation transfer function to evaluate the early visual quality after full femtosecond laser refractive surgery / 中华实验眼科杂志

Background Full femtosecond laser refractive surgery has been generally applied,but the improvement of visual quality after surgery is a vital problem.It is well-known that modulation transfer function (MTF) is a major evaluation indicator.Objective To investigate the change of the MTF of operated eyes after the full femtosecond laser refractive surgery.Methods A retrospective series of cases study was adopted.Forty eyes of 23 patients with the spherical equivalent of-2.25 to-5.75 D who received full femtosecond laser refractive surgery were enrolled in Nanjing General Hospital of Nanjing Military Command from July to October,2012.The change of visual acuities was analyzed and compared among before operation and 1 day,1 week and 1 month after operation.MTF value in total aberration,low and high order aberrations under the 3.0 mm and 6.0 mm pupil size conditions were detected with i-Trace Visual Function Analyzer at above time points.The MTF values among various time points,between different pupil diameters and different spatial frequencies (5,10,15,20,25 c/d) were compared respectively.Results Compared with the preoperation,the visual acuity improved in postoperative 1 day,1 week and 1 month,showing a significant improvement among various time points (F =10.341,P =0.000).Corrected diopter was 3.795 D at average.MTF values under the 3 mm pupil diameter gradually elevated with the lapse of time after operation,without significant differences among different time points whatever total aberration,low and high order aberrations(all at P＞0.05).The MTF values under 6 mm pupil diameter of total aberration and low order aberration were significantly higher in postoperation than those in preoperation(all at P＜0.05),but no significant difference was seen in MTF of high order aberration among various time points (F =0.260,P =0.854).Compared with the MTF under the 3 mm pupil diameter,those of low and high order aberrations under the 6 mm pupil diameter considerably declined in preoperation and postoperative 1 month (preoperation:P =0.050,0.001 ; postoperation:P =0.012,0.001).MTF values under the 3 mm pupil diameter were not different at various spatial frequencies (all at P＞ 0.05).However,MTF values under the 6 mm pupil diameter were gradually increased from preoperation through postoperative 1 month at 10,15,20 and 25 c/d (P =0.044,0.043,0.024,0.014).Conclusions Full femtosecond laser refractive surgery can eliminate low aberration,increase the MTF and acuity,and therefore improve the visual quality.MTF is one of the key indicators assessing visual quality after full femtosecond laser refractive surgery.