Objective To observe the rate of iris vessels exposure and analyze its relevant factors in normal full-term neonates.Methods A retrospective study.1855 normal full term neonates,including 947 boys and 908 girls,were enrolled.The mean gestational age (GA) was (38.84±1.10) weeks and mean birth weight (BW) was (3 396.52±402.08) g.There were 1235 neonates from normal term vaginal delivery,402 cases of cesarean delivery and 218 cases of forceps delivery.All neonates were examined with hand-held portable slit lamp biomicroscopy within 1 to 3 days after birth by two trained ophthalmologist respectively.Iris vessels exposure was defined as radial red blood vessels along iris fibers.Infants were divided into iris vessels exposure group and iris vessels unexposed group according to the findings of slit lamp biomicroscopy.78 infants with iris vessels exposure were followed up for 42 days after birth till the iris vessels can't be seen under microscope.The differences between the two groups were compared for gender,mode of delivery (MOD),GA,BW and body length (BL).Multiple logistic regressions were used to determine the factors related to iris vessels exposure.Results There were 298 neonates with iris vessels exposure among 1855 neonates and the rate was 16.1％.1557 neonates (83.9％) had unexposed iris vessels.There were no different in gender (x2=0.551) and MOD (x2=3.036) between iris vessels exposure group and unexposed group (P＞0.05),while the differences in GA (x2=47.216),BW (t=4.603) and BL (t=3.936) between the two groups were statistically significant (P=0.000).Multiple logistic regression analysis revealed that only GA (β=-0.291,odds ratio=0.747,95％ confidence interval:0.656-0.85 1,P=0.000) was correlated to iris vessels exposure significantly.The iris vessels couldn't be seen in 77 of 78 infants with iris vessels exposure when followed up to 42 days.Conclusions The iris vessels exposure in normal full-term neonates is frequently observed.There is a significant inverse correlation between GA and iris vessels exposure.

Objective:To prepare a drug release system of drug-loaded cross-linked decellularized corneal stromal lenticules and evaluate its drug release characteristics in vitro. Methods:Lenticules were obtained during femtosecond laser-assisted small incision lenticule extraction (SMILE) surgery in Chongqing Aier Ophthalmology Hospital.Decellularized corneal stromal lenticules were prepared using high concentration sodium chloride (NaCl) combining nuclease.The decellularized corneal stromal lenticules were randomly divided into normal group, 0.5% levofloxacin group, 3% levofloxacin group and 5% levofloxacin group, with 4 lenticules in each group.The lenticules did not receive any treatment in the normal group, and drug-loading those were soaked in different doses of levofloxacin solution for three hours according to grouping.In the crosslinking test, 12 decellularized corneal stromal lenticules were randomly divided into non-crosslinking group, 0.01 mmol 1-(3-dimethylamino) propylimine (EDC) group, 0.05 mmol EDC group and 0.25 mmol EDC group.The lenticules for cross-linking were soaked in different contents of mixed solution of EDC with N-hydroxysuccinyl (NHS) for four hours respectively according to grouping, and then in 3% levofloxacin solution for three hours.Only 3% levofloxacin solution soaking was carried in the non-crosslinking group.High performance liquid chromatography (HPLC) was employed to detect the drug release concentration of the lenticules, and spectral scanning method was performed to measure light transittance of the lenticules.The surface ultrastructure of the decellularized lenticules among different cross-linking groups was examined and compared with scanning electron microscope.The use of the human corneal lenticules was approved by an Ethics Committee of Chongqing Aier Ophthalmology Hospital (No.2019012). Written informed consent was obtained from each patient before surgery.Results:The release concentrations of decellularized corneal stroma lenticules were significantly different at 1 day, 7, 14, and 21 days among 0.5%, 3%, and 5% levofloxacin group ( P<0.05) or also among the 0.01 mmol EDC, 0.05 mmol EDC, and 0.25 mmol EDC cross-linked groups ( P<0.01). The drug release concentrations in 0.05 mmol EDC group were the highest at various time points, and the release time of the three cross-linked groups lasted until 21 days after release concentrations of decellularized corneal stroma lenticules.The drug release concentrations in cross-linked groups and non-crosslinking group were gradually declined with the prolong of drug-loading time, showing a significant difference at different time points ( P<0.05). The transmittance of the lenticules was (88.68±1.19)% and (91.55±1.16)% in the non-crosslinking group and normal group, respectively, with no significant difference ( P>0.05). The average transmittance of the lenticules was significantly reduced in the drug-loaded groups compared with the normal group ( P<0.05). The smaller collagen fiber voids and closely arranged collagen fibers were displayed in the cross-linking groups under the scanning electron microscope with the best effect in the 0.25 mmol EDC group. Conclusions:EDC/NHS cross-linking can improve the drug-loading effect of decellularized corneal stromal lenticules probably by lessening collagen fiber voids.The drug-loaded cross-linked decellularized corneal stromal lenticules have a good drug release effect in vitro.

Objective To investigate the characteristics of brain network based on brain electrical activity induced by somatosensory electrical stimulation,and to provide a theoretical basis for further understanding the mechanism of brain neural plasticity induced by somatosensory electrical stimulation.Methods Ten healthy subjects were selected and a somatosensory electrical stimulation experiment was constructed based on the directed transfer function (DTF).In the experiment,the DTF causal connection matrixes of the 32-channel EEG data of Delta,Theta,Alpha and Beta bands were obtained under the somatosensory electrical target and non-target stimulation,and the differences of clustering coefficient and global efficiency between two stimulation states were contrasted based on graph theory.Results Under the target stimulation and non-target stimulation states,the regions with stronger DTA causal connections were mainly concentrated in FCz,Cz,CPz and Pz channels.The causal connection intensity under target stimulation state was greater than that of non-target stimulation.Also,in the Delta,Theta,and Alpha bands,the clustering coefficient under the target stimulation state was significantly higher than that in the non-target stimulation state (P＜0.05).In the Delta and Theta bands,the global efficiency of the target stimulation state was significantly higher than that of the non-target stimulation state (P＜0.05).Conclusions Somatosensory electrical stimulation can activate and induce EEG brain networks.In the target stimulation state,the role of the parietal lobe in the EEG causal network is enhanced,which helps to induce attention to specific brain region plasticity,and thus realizing the nerve rehabilitation in the brain regions of interest.While in the non-target stimulation state,the synergistic interactions between brain regions were enhanced,which helps to activate and induce a wide range of associations in the whole brain network,so as to promote the global neural activity in the brain.