Influence of transient intraocular pressure elevation during laser in situ keratomileusis on rabbit retina thickness.

AIM: To utilize tissue micro measurement to study the effect of transient high intraocular pressure (IOP) induced by different durations of suction during laser in situ keratomileusis (LASIK) on rabbit retina thickness. METHODS: Sixty healthy New Zealand white rabbits were randomly divided into a control group, and 3 negative-pressure suction groups (20s group, 45s group, and 3min group) and each group was comprised of 15 rabbits (30 eyes); the latter 3 groups were the transient high IOP models. The retinal tissue around the papilledema was separated. Hematoxylin and eosin (HE) staining was carried out to generate slices for light microscopy. The changes in the retina thickness values of each layer were measured for all animals in each group at different postoperative recovery periods and compared with the values recorded for the animals in the control group. The thickness of the retinal tissue showed a normal distribution. The ANOVA was performed by using SPSS13.0 statistic software. RESULTS: In the comparison between the 20s and 45s negative-pressure suction groups and the control group, no significant differences were observed, except at 14d. Significant difference was observed between the 3min negative-pressure suction group and the control group, and the retina thickness value of each layer reached a peak at 14d after repair. CONCLUSION: Conventional negative suction during LASIK may not lead to significant changes in retinal tissue thickness; however, if the suction duration is increased to 3min, it will cause significant changes in retinal tissue thickness.

[Preparation and Characterization of Quinone Functional Polymer Biocarrier (PET-AQS) for Biodenitrification Catalysis].

Anthraquinone sodium sulfonate (AQS) was immobilized on polyethylene terephthalate (PET) by chemical synthesis, forming quinone functional polymer biocarrier (PET-AQS), and its characteristics in biodenitrification catalysis were analyzed. Quinone group was demonstrated to be successfully immobilized on the surface of the polymer and the concentration of immobilized quinone was 0.140 6 mmol x g(-1) by Attenuated Total Reflectance Spectrometry (ATR-IR) and Energy Dispersive Spectrometry (EDS). The PET-AQS could accelerate biodenitrification. The relationship between the denitrification rate constant (K(x)) and the PET-AQS concentration (C(PET-AQS)) obeyed the pseudo-zero order kinetics. After ten rounds of recycling in the biodenitrification system with approximately 0.056 2 mmol quinone, the denitrification rate was kept at more than 1.2 times of the blank system. This indicated that PET-AQS exhibited a good operational stability and was beneficial to practical application.

[Preparation and application of the quinonyl chloromethylation polystyrene in biological treatment of wastewater].

The technology of non-water-soluble mediator anaerobic biological catalysis has attracted more and more attention in the field of environment technology. In this study, five kinds of quinonly compounds were grafted on the chloromethylation polystyrene macromolecular carrier by Friedel-Crafts reaction. Reaction factors of temperature and molar ratio for the 1,4-naphthoquinone grafting carrier were optimized, and the optimal temperature was 78 degreesC while the optimal molar ratio of 1, 4-naphthoquinone and chloromethylation polystyrene was 2: 1. Fourier infrared spectrum analysis confirmed that the quinone groups were successfully grafted on the macromolecular backbone chloromethylation polystyrene. Catalysis using the five kinds of quinonly materials as non-water-soluble redox mediators enhanced the biological denitrification rate and the decoloration of azo dyes, meanwhile these materials showed good reusability in the biodegradation of azo dye. This study developed a new method for the preparation of quinonly materials and revealed a new field in the technology of mediator catalysis.

[Study on gene expression profiles of rabbit retina transient IOP during LASIK].

OBJECTIVE: To detect the changes of gene expression profiles of retina by way of gene chip technology, and to investigate possible molecular pathogenesis of RGCs apoptosis caused by transient high IOP. METHODS: Twenty-two new Zealand white rabbits were randomized to experimental control and negative pressure suction 3 min groups. The rabbit were executed at different time points of post-LASIK, such as postoperative instant, 7 d, 10 d, then the total RNA of retinal tissue was extracted to detect gene expression profiles by the way of Agilent rabbit one-way gene chip. RESULTS: Instant after negative pressure suction, the genes differential expressed had 704 genes. Of these, the expression of 485 genes were unregulated and 219 genes down regulated. The higher expression of apoptosis genes were CRYAA, CRYAB, TLR3 and KRT18. 7 d after negative pressure suction, the genes differential expressed had 482 genes. Of these, the expression of 178 genes were unregulated and 304 genes down regulated. The higher expression of apoptosis genes were CRYAB, IL1-BETA and IL1R1. 10 d after negative pressure suction, the genes differential expressed had 402 genes. Of these, the expression of 213 genes were unregulated and 189 genes down regulated. The higher expression of apoptosis genes were CRYAB, CRYBA3, CRYBB2, IL1-BETA and IL1R1. CONCLUSION: The gene expression had changed after negative pressure suction. The genes with higher fold change protected RGCs from apoptosis.

[IR study on the thermal decomposition IR of the cationic fenugreek gum].

The title complexes shown as cationic fenugreek gum were prepared. The thermal decomposition process of fenugreek gum and cationic fenugreek gum was studied quantitatively by means of thermogravimetric analysis an dinfrared spectroscopic measurement of samples after heating at different temperatures. Additionally, according to the fact that the absorbance peak changes and theanalysis of TG-IR of cationic fenugreek gum at different temperatures, it can be drawn that the thermal decomposition of the cationic fenugreek gum might lead to a possible thermal-cracking process.