Enhanced virulence of genetically engineered Autographa californica nucleopolyhedrovirus owing to accelerated viral DNA replication aided by inserted ascovirus genes.

Genetic engineering technology is an ideal method to improve insecticidal efficiency by combining the advantages of different pathogenic microorganisms. Thus, six ascovirus genes were introduced into the genomic DNA of Autographa californica nucleopolyhedrovirus (AcMNPV) to possibly transfer the intrinsically valuable insecticidal properties from ascovirus to baculovirus. The viral budded virus (BV) production and viral DNA replication ability of AcMNPV-111 and AcMNPV-165 were significantly stronger than that of AcMNPV-Egfp (used as the wild-type virus in this study), whereas AcMNPV-33 had reduced ones. AcMNPV-111 and AcMNPV-165 also exhibited excellent insecticidal efficiency in the in vivo bioassays: AcMNPV-111 showed a 24.1% decrease in the LT50 value and AcMNPV-165 exhibited a 56.3% decrease in the LD50 value compared with AcMNPV-Egfp against the 3rd instar of Spodoptera exigua larvae, respectively. Furthermore, the size of the occlusion bodies (OBs) of AcMNPV-33, AcMNPV-111, and AcMNPV-165 were significantly increased compared to that of AcMNPV-Egfp. AcMNPV-111 and AcMNPV-165 had stable virulence against the 2nd to 4th instars tested larvae and higher OB yield than AcMNPV-Egfp in the 3rd and 4th instar larvae. Correlation and regression analyses indicated that it is better to use 5 OBs/larva virus to infect the 2nd instar larvae to produce AcMNPV-111 and 50 OBs/larva virus to infect the 3rd instar larvae to produce AcMNPV-165. The results of this study obtained recombinant viruses with enhanced virulence and exhibited a diversity of ascovirus gene function based on the baculovirus platform, which provided a novel strategy for the improvement of baculovirus as a biological insecticide.

Effects of 0.05% cyclosporine eye drops(Ⅱ)on corneal nerves of patients with moderate to severe dry eye / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the efficacy of domestic cyclosporine A(CsA)in dry eye and its effect on sub-basal nerves(SBN)by observing quantitative and morphological changes in corneal SBN of patients with moderate to severe dry eye before and after the treatment with 0.05% CsA eye drops(Ⅱ).METHODS: In this prospective study, a total of 20 patients(20 eyes)with moderate to severe dry eye who admitted to the ophthalmology department of the Affiliated Eye Hospital of Nanchang University from December 2020 to January 2022 were selected. They were treated with domestic CsA and followed up for 3mo. Clinical evaluation was carried out at baseline and at 3mo after treatment. The changes in clinical symptoms, signs and morphology and quantity of SBN were observed.RESULTS: The ocular surface disease index(OSDI)score, the tear break-up time(TBUT), Schirmer Ⅰ, corneal fluorescein staining(CFS)score were significantly improved at 3mo after treatment. Confocal microscopy data analysis showed that SBN density increased from 13.49±5.43 mm/mm2 to 14.93±5.34 mm/mm2(P<0.001), nerve curvature scores decreased from 2.86±0.92 to 2.31±0.75(P<0.001), number of beaded structure decreased from 1.45±0.67/100μm to 1.07±0.45/100μm(P<0.001), and the number of dendritic cell(DC)decreased from 5.83±3.28 per frame to 3.67±2.24 per frame at 3mo after treatment(P<0.001). The number of DC was positively correlated with the number of branch nerves, the grade of nerve curvature and the number of nerve bead.(rs=0.27, P=0.045; rs=0.407, P<0.01; rs=0.486, P<0.01).CONCLUSIONS: Nerve injury was positively correlated with corneal inflammation caused by dry eye, and 0.05%CsA eye drops(II)could effectively inhibit inflammation and improve the morphology and quantity of corneal SBN. Observation of corneal SBN via in vivo confocal microscopy can be used as an effective method to evaluate the therapeutic effect of dry eye patients.

Comparison of the stability of different concentrations of fluorescein sodium on the detection of tear film rupture time / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To analyze the stability of different concentrations of fluorescein sodium solution on the detection of tear break-up time(TBUT).METHODS:A retrospective study. A total of 150 cases(150 eyes)who came to our dry eye clinic with good cooperation from August 2019 to September 2021 were selected for the study, and the subjects were randomly divided into five groups, which were fluorescein sodium(FLS, 0.5%), FLS(1.0%), FLS(1.5%), FLS(2.0%)and fluorescein sodium parallel(FLSP), with 30 patients in each group(all the right eyes were the subject eyes). Each group was dripped with the corresponding fluorescein sodium. The FLSP group was the fluorescent test strip detection group. The slit lamp image scores of different concentration groups were compared, the survival time of sodium fluorescein at the instant, 2, 5, 10, 15 and 30min points was observed in each group, and the mean value of TBUT in each group was recorded.RESULTS: The image score of FLS(0.5%)group was significantly higher than that of the other four groups(t=7.746, 21.483, 116.190, 38.730, all P<0.01). The image score of FLS(1.0%)group was significantly higher than that of FLS(1.5%)and FLS(2.0%)group(t=10.742, 15.492, all P<0.01). The survival time of fluorescein in FLS(0.5%)group was significantly shorter than that of the other four groups(t=8.226, 7.458, 9.159, 12.347, all P<0.01). The survival time of fluorescein in FLS(1.5%)group was significantly longer than that of FLS(1.0%)and FLS(2.0%)group(t=15.428, 13.274, all P<0.05). TBUT in FLS(0.5%)group was significantly higher than that of the other four groups at 2min(t=22.767, 22.345, 15.494, 17.213, all P<0.01), and was significantly lower than that of the other four groups at 10min(t=23.266, 25.353, 10.183, 22.025, all P<0.01). The mean first TBUT of FLS(1.5%)group was significantly shorter than that of the other four groups(t=25.236, 21.374, 19.658, 72.341, all P<0.01), and the mean first TBUT of FLSP group was significantly longer than that of the other four groups(t=22.487, 30.267, 60.247, 40.857, all P<0.01). There was no significant correlation between TBUT and ocular surface disease index(OSDI)and tear river height(rs=-0.072, 0.219, P=0.689, 0.112). TBUT was positively correlated with tear secretion(rs=0.674, P<0.01).CONCLUSION: FLS(0.5%)had higher image quality but it was only suitable for observing staining within 5min, and the FLSP group was more suitable for clinical observation of corneal fluorescence staining for a longer period; FLS(1.5%)was the most stable and reliable concentration and dose for the detection of TBUT.