Preparation of hollow CuO@SiO2 spheres and its catalytic performances for the NO + CO and CO oxidation.

The hollow CuO@SiO2 spheres with a mean diameter of 240 nm and a thin shell layer of about 30 nm in thickness was synthesized using an inorganic SiO2 shell coating on the surface of Cu@C composite that was prepared by a two-step hydrothermal method. The obtained hollow CuO@SiO2 spheres were characterized by ICP-AES, nitrogen adsorption-desorption, SEM, TEM, XRD, H2-TPR, CO-TPR, CO-TPD and NO-TPD. The results revealed that the hollow CuO@SiO2 spheres consist of CuO uniformly inserted into SiO2 layer. The CuO@SiO2 sample exhibits particular catalytic activities for CO oxidation and NO + CO reactions compared with CuO supported on SiO2 (CuO/SiO2). The higher catalytic activity is attributed to the special hollow shell structure that possesses much more highly dispersed CuO nanocluster that can be easy toward the CO and NO adsorption and the oxidation of CO on its surface.

Clinical observation on juvenile macular hole without trauma and hypermyopia.

PURPOSE: To investigate the clinical characteristics of juvenile macular hole without trauma and hypermyopia, and research the mechanism of macular hole. METHODS: Sixty-seven patients less than 40 years of age were studied retrospectively from June 1998 to March 2003. Five cases (7 eyes) aged from 22 to 38 years were reported and the clinical characteristics that had macular hole without trauma or hypermyopia were summed up. RESULTS: There was 1 male and 4 females with visual acuity from 0.08 to 0.8. The images of optical coherence tomography (OCT) showed full thickness macular hole in 5 patients (7 eyes), and the diameters were from 87 to 1043 microm. Among them, 2 cases were combined with retina pigmentosa; 1 case with binocular Coat's disease; 1 case had bilateral macular hole combined with Eagles' disease; 1 case was combined with 2-2.5PD old retinochoroidal lesion under middle-peripheral fundus, and 1.5 PD retinal pigment epithelium (RPE) defect on the optical disk. CONCLUSION: The juvenile macular hole without trauma and hypermyopia combined the different retina vascular damages and the RPE defects.

Removal of silicone oil from aphakia: use of a self-sealing corneal incision.

PURPOSE: To report and illustrate a modified and simple technique for silicone oil removal from aphakic eyes. DESIGN: Interventional case series. METHODS: Eighteen eyes of 18 patients who once had pars plana vitrectomy and lensectomy combined with silicone oil tamponade underwent silicone oil removal using a self-sealing corneal incision. RESULTS: All of the 18 silicone oil removal procedures performed had clear corneal incisions, which did not require suturing. CONCLUSIONS: Silicone oil can be removed successfully from aphakia using the self-sealing corneal incision under local anesthesia.

Optical coherence tomography's diagnostic value in evaluating surgical impact on idiopathic macular hole.

OBJECTIVE: To identify the characteristics of and evaluate surgical impact on idiopathic macular hole (IMH) by using an optical coherence tomography (OCT) scanner. METHODS: Sixty-five cases (70 eyes) experiencing IMH were examined using OCT, then graded by their clinical characteristics. Nineteen cases (19 eyes) were scanned and measured using OCT before and after surgery. RESULTS: Of the 70 eyes,the number of stage I-IV macular holes were 11, 12, 36 and 11, respectively. For stage I holes, the OCT images revealed flattened or nonexistent fovea and minimally reflective space within or beneath the neurosensory retina; stage II holes appeared to be full-sized with attached operculum and surrounding edema; stage III holes were also full-sized with surrounding edema; finally, stage IV holes were full-sized and completely separated the posterior hyaloid membrane from the retina. Through quantitative measurements, OCT determined that the values for mean hole diameter, mean halo diameter and mean thickness of the hole's edge were reduced from 570.95 +/- 265.59 to 337.05 +/- 335.95 microm, 1043.53 +/- 278.8 to 695.00 +/- 483.00 microm and 389.78 +/- 60.58 to 298.78 +/- 109.80 microm, respectively in 19 IMH cases after surgery. In 17 eyes, the holes or halos eventually closed or were reduced in size, or the edges of the holes thinned out. The anatomic successful rate of the surgery was 89%. CONCLUSION: OCT can exhibit the characteristics of IMH and measure the diameter of holes quantitatively. This method can also judge the surgical impacts of IMH objectively, accurately and effectively.