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Biomedical subjects

Yong-Ping Li

Publications and source records attributed to Yong-Ping Li.

8 recordsLinked to original sources

[Genetic and correlation analysis for agronomic traits in flue-cured tobacco (Nicotiana tabacum L.)].

By using a genetic model including additive and dominance effects and their interaction with environments, 7 agronomic traits were analyzed for a diallel design in 4 environmental conditions with 14 flue-cured tobacco varieties (or breeding lines) and their 41 F1 crosses. It was revealed that additive effects were the major genetic component for plant height, internode length, and width of leaves. Number of leaves and length of leaves were mainly controlled by dominance x environment interaction effects. Additive x environment interaction effects and dominance x environment interaction effects played a major role for girth of stem. Yield performance was mainly controlled by additive effects and dominance x environment interaction effects. The varieties adapted to local environments tended to have highly positive additive effects. Dominance effects and the dominance x environment interaction effects could perform differently in positive or negative direction for many crosses. The breeding program for hybrids should consider the adaptation of hybrids to specific ecological environments. The analysis of correlation among agronomic traits indicated that most of phenotypic, genotypic, additive and dominance correlation coefficients were positive. Additive correlations were predominance in genetic correlations for most pairs of traits. Yield can be improved by indirect selection on plant height.

Genotype↗

Creation of a three-dimensional optical chain for controllable particle delivery.

We propose a design for producing a conveyable quasi-periodic optical chain that can stably trap and deliver multiple individual particles in three dimensions at different planes near the focus. A diffractive optical element (DOE) is designed to spatially modulate the phase of an incoming radially polarized beam. For a tighly focused beam, a three-dimensional (3D) optical chain can be formed because of the difference in the Gouy phase shift from two concentric regions of the DOE. A desired number of particles can be stably tweezed one by one with individual 3D volumes in this trapping structure. By controlling the phase modulation of the incident beam, one can manipulate the interference pattern to accelerate and transport trapped particles along the optical axis in a prescribed way.

Computer Simulation↗

[Mechanism of keratinocyte growth factor-2 accelerating corneal epithelial wound healing on rabbit alkali burned cornea].

OBJECTIVE: To evaluate the curative effect of KGF-2 on the alkali-injured rabbit eye and to investigate the mechanism of KGF-2 accelerating corneal epithelial wound healing. METHODS: Alkali burn was produced in 24 corneas from 24 New Zealand rabbits. Four groups were randomly divided. Three groups (A, B, and C groups) were treated with KGF-2 solution (1, 50, 100 microg/ml, respectively), and one group (D group) was treated with phosphate-buffered saline (PBS) solution. The injured eyes were photographed after the fluorescence staining with a slit lamp and the pictures were analyzed with computer-aided picture analysis system to calculate the rate of corneal epithelial healing. Morphologic and immunohistological examinations (using P63, AE5 and EGFR antibodies) of the cornea were performed. RESULTS: KGF-2 at dosages ranging from 1 microg/ml to 100 microg/ml could enhance the cornea wound healing process. After 24 hours, epithelial healing rate of the 100 microg/ml KGF-2 group and the PBS treated group was 74% and 40%, respectively (P < 0.05). The corneal epithelial healing rate of each group was variable after four days and achieved complete healing after ten days. The P63 positive cells in KGF-2 groups appeared not only in the limbal area but also in the central area. For example, on the seventh day, in the limbal area, the P63 positive cells in the 100 microg/ml KGF-2 group, the PBS treated group and the normal group were 53.8 +/- 2.6, 29.5 +/- 2.2 and 17.0 +/- 2.1, respectively (P = 0.000). At the same time, the P63 positive cells in the non-limbal area in the 100 microg/ml KGF-2 group, the PBS treated group and the normal group were 69.5 +/- 2.8, 19.5 +/- 2.8 and 0, respectively (P = 0.000). CONCLUSIONS: These results suggested KGF-2 can stimulate the limbal epithelial stem cells to migrate to the central cornea. KGF-2 can accelerate the healing of alkali burned cornea.

Alkalies↗

[Genetic contribution of agronomic traits to yield in flue-cured tobacco (Nicotiana tabacum L.)].

In order to understand the genetic contribution of six agronomic traits to yield, 14 flue-cured tobacco varieties (or breeding lines) and their 41 F1 crosses were used for multivariable conditional analysis. The contribution of additive variance of plant height to yield was larger than other agronomic traits. The largest contribution of dominant variance to yield was due to the length of middle leaves. All agronomic traits investigated had small contribution to yield due to additive x environment interaction effects and dominant x environment interaction effects. No identical trait of different parents showed the largest contribution to additive effect of yield. This could be resulted from the fact that each parent had its own genetic and developmental characterization. The dominant effects of yield were mainly influenced by length of middle leaves in most crosses. Length of middle leaves could be served as ameasurement to indirectly select the cross parent having high dominant effect of yield.

Biomass↗

Vector iterative algorithm for the design of diffractive optical elements applied to uniform illumination.

A vector angular-spectrum iterative algorithm for the design of diffractive optical elements to produce uniform illumination is described. In the algorithm, the variation of beam polarization is related to a unit wave vector and a random mixture of intensity is used for super-Gaussian beam shaping [corrected]. The simulated results show that approximately 95.3% of the incident energy has converged into the desired region. The greatest profile error and the mean-square error of intensity fitted to the corresponding parameters of the 100th-power super-Gaussian function are approximately 8 x 10(-4) and 3.5 x 10(-3), respectively.

Journal Article↗

[An experiment study of in vitro induced antitumor immune responses by vaccination of tumor lysate-pulsed dendritic cells to kill SO-RB(50)].

OBJECTIVE: To investigate induced antitumor immune responses by vaccination of tumor lysate-pulsed dendritic cells (DC) to kill retinoblastoma cells SO-RB(50). We hope to offer new approach for the treatment of patients with retinoblastoma. METHODS: DC was pulsed with RB tumor lysates in vitro and incubated with autologous lymphocytes to induce antigen specific CTL (cytotoxic T lymphocyte, CTL). SO-RB(50) cells were used as target cells and Raji cells were used as control target cells. Cytotoxicity of CTL was evaluated by MTT method (methyl thiazolyl letrazolium). The specific cytotoxicity of CTL to SO-RB(50) and Raji cells was compared. The cytotoxicity of CTL from RB and normal subjects was compared between these two groups. RESULTS: Antigen specific CTL showed greater cytotoxicity to SO-RB(50) than Raji cells, the difference was statistically significant, P < 0.01. The cytotoxicity was dose-dependent to the ratio of CTL/target cell. The nonspecific cytotoxicity to Raji cells was the same in CTL from RB patients and normal subjects, P > 0.05. The specific cytotoxicity of CTL from RB patients to SO-RB(50) was weaker than that from the healthy subjects, P < 0.01. CONCLUSION: DC pulsed with RB tumor lysate in vitro can induce antigen specific CTL which can kill the SO-RB(50) target cells specifically. This method may have potential value of therapy for the RB patients.

Cancer Vaccines↗

Systemic dissemination of viral vectors during intratumoral injection.

Intratumoral injection is a routine method for local viral gene delivery that may improve interstitial transport of viral vectors in tumor tissues and reduce systemic toxicity. However, the concentration of transgene products in normal organs, such as in the liver, may still exceed normal tissue tolerance if the products are highly toxic. The elevated concentration in normal tissues is likely to be caused by the dissemination of viral vectors from the tumor. Therefore, we investigated transgene expression in the liver, the serum, and a mouse mammary carcinoma (4T1) in mice after intratumoral injection of adenoviral vectors for mouse interleukin-12, luciferase, enhanced green fluorescence protein, or beta-galactosidase. We also performed numerical simulations of virus transport in tumors after intratumoral injection, based on the Krogh cylinder model. Our experimental data and numerical simulations demonstrated that virus dissemination was significant in mice and it occurred mainly during the intratumoral injection. To reduce virus dissemination, we mixed these vectors with a viscous alginate solution and injected the mixture into the tumors. Our data showed that the alginate solution could significantly reduce virus dissemination while having minimal effects on transgene expression in tumors and on interleukin-12-induced tumor growth delay. These data suggest that virus dissemination is a potential problem in local viral gene therapy of cancer and that the dissemination could be significantly reduced by the alginate solution without compromising the efficacy of gene therapy.

Adenoviridae↗