Overexpressing NeuroD1 reprograms Müller cells into various types of retinal neurons.

The onset of retinal degenerative disease is often associated with neuronal loss. Therefore, how to regenerate new neurons to restore vision is an important issue. NeuroD1 is a neural transcription factor with the ability to reprogram brain astrocytes into neurons in vivo. Here, we demonstrate that in adult mice, NeuroD1 can reprogram Müller cells, the principal glial cell type in the retina, to become retinal neurons. Most strikingly, ectopic expression of NeuroD1 using two different viral vectors converted Müller cells into different cell types. Specifically, AAV7m8 GFAP681::GFP-ND1 converted Müller cells into inner retinal neurons, including amacrine cells and ganglion cells. In contrast, AAV9 GFAP104::ND1-GFP converted Müller cells into outer retinal neurons such as photoreceptors and horizontal cells, with higher conversion efficiency. Furthermore, we demonstrate that Müller cell conversion induced by AAV9 GFAP104::ND1-GFP displayed clear dose- and time-dependence. These results indicate that Müller cells in adult mice are highly plastic and can be reprogrammed into various subtypes of retinal neurons.

[Comparison of three HIV antibody confirmatory assay kits in confirming early HIV infection].

OBJECTIVE: This study was to compare the performance of three HIV antibody confirmatory assay kits in confirming early HIV infection. METHODS: Five HIV antibody-positive plasma specimens were ten-fold serially diluted and then detected by ELISA. The above diluted specimens were detected with the following three HIV antibody confirmatory assay kits to analyze their sensitivity, including Wantai-RIBA (Recombinant immunoblot assay, Beijing Wantai Biological Pharmacy, China), MP-WB (HIV Blot 2.2 WB, MP Biomedicals Asia Pacific Pte. Ltd., Singapore) and INNO-LIA (INNO-LIA(TM) HIV I/II Score, Innogenetics N.V., Belgium), respectively. These kits were further used to detect 48 ELISA-reactive specimens from 11 sets of HIV seroconversion specimens (a total of 48 samples) which were previously detected as HIV antibody-positive by ELISA. RESULTS: When 5 samples were diluted to 100 fold, Wantai-RIBA still can detect them positive. Among the 48 HIV antibody-positive specimens detected with ELISA, the confirmation positive rate for Wantai-RIBA, MP-WB and INNO-LIA were 97.92% (47/48), 81.25% (39/48) and 91.67% (44/48), respectively. There was statistically significant difference between the confirmatory results of Wantai-RIBA and MP-WB (χ(2) = 6.13, P < 0.05), as well as between those of INNO-LIA and MP-WB (χ(2) = 5.48, P < 0.05); however, there was no statistically significant difference between those of Wantai-RIBA and INNO-LIA (χ(2) = 1.33, P > 0.05). For other six HIV seroconversion panels containing indeterminate specimens, the average seroconversion period of time for Wantai-RIBA, MP-WB and INNO-LIA were 0.7, 13.3 and 3.7 days, respectively. CONCLUSION: Compared with MP-WB, Wantai-RIBA and INNO-LIA could reduce the window period to confirm early HIV infection.

[Study of plasma temperature measurements for oxygen discharge].

A radio-frequency discharge setup was constructed by two shell-shaped copper electrodes and a 30 cm long pyrex glass tube (i. d. = 1.65 cm) to examine the gas temperature of oxygen plasma in electric discharge oxygen iodine laser. The discharge was supplied by a 500 watt, 13.56 MHz radio-frequency power. The gas pressure in the discharge cavity was 1 330 Pa. The temperature of oxygen discharge plasma was measured by using the P branch of O2 (b, v = 0) rotational emission spectrum. Two methods were used to deduce the oxygen gas temperature. They are Boltzman plotting method and computer simulating spectrum method, respectively. Gauss fitting method was used to distinguish spectrum peaks for lower resolution spectrum. The spectrum peak area was used to characterize the optical emission intensity. The gas temperature of oxygen discharge plasma was obtained by Boltzmann plotting method. Alternatively, the optical emission spectrum was simulated by computer modeling with spectrometer slit function which was obtained by He-Ne laser. Consequently, the gas temperature of oxygen plasma was obtained by comparing the computer simulating spectrum and the experimentally observed spectrum according to the least square fitting rule. The measurement results with the two methods agree well. It was concluded that the simple optical technique can be used conveniently in the temperature diagnostics of oxygen radio-frequency discharge plasma.