Preparation and Characterization of Modified Polysulfone with Crosslinked Chitosan-Glutaraldehyde MWCNT Nanofiltration Membranes, and Evaluation of Their Capability for Salt Rejection.

Nanofiltration membranes were successfully created using multi-walled carbon nanotubes (MWCNTs) and MWCNTs modified with amine (MWCNT-NH2) and carboxylic groups (MWCNT-COOH). Chitosan (CHIT) and chitosan−glutaraldehyde (CHIT-G) were utilized as dispersants. Sonication, SEM, and contact angle were used to characterize the as-prepared membranes. The results revealed that the type of multi-walled carbon nanotubes (MWCNT, MWCNT-COOH and MWCNT-NH2) used as the top layer had a significant impact on membrane characteristics. The lowest contact angle was 38.6 ± 8.5 for the chitosan-G/MWCNT-COOH membrane. The surface morphology of membranes changed when carbon with carboxylic or amine groups was introduced. In addition, water permeability was greater for CHIT-G/MWCNT-COOH and CHIT-G/MWCNT-NH2 membranes. The CHIT-G/MWCNT-COOH membrane had the highest water permeability (5.64 ± 0.27 L m−2 h−1 bar−1). The findings also revealed that for all membranes, the rejection of inorganic salts was in the order R(NaCl) > R(MgSO4).

Optic Disc Hemorrhages and Laminar Disinsertions in Glaucoma.

PURPOSE: To determine whether structural abnormalities of the lamina cribrosa explain the presence of optic disc hemorrhages, we determined the spatial concordance between disc hemorrhages and laminar disinsertions from the sclera. DESIGN: Prospective noninterventional study. PARTICIPANTS: From open-angle glaucoma patients followed up prospectively, we identified 52 eyes of 46 open-angle glaucoma patients with optic disc hemorrhage (ODH+ group) in at least 1 optic disc photograph during follow-up. We also identified 52 control eyes of 46 glaucoma patients in whom no disc hemorrhage was detected (ODH- group). METHODS: Enhanced depth imaging optical coherence tomography of the optic nerve head (24 radial scans) was performed. The scans were de-identified and a trained observer masked to all clinical information determined the presence of laminar disinsertions in each of the 48 positions with a confidence score of 1 (least certain) to 5 (most certain). Only disinsertions with a score of 3 or more were included in the analysis. MAIN OUTCOME MEASURES: Frequency and spatial concordance between disc hemorrhages and laminar disinsertions. RESULTS: The median age, visual field mean deviation, and follow-up period of the ODH+ and ODH- groups was 77.5 and 70.8 years, -5.20 and -4.70 dB, and 10.4 and 9.9 years, respectively. There were 84 hemorrhages recorded in the ODH+ group. There were laminar disinsertions in 50 eyes (96%) in the ODH+ group and in 27 eyes (52%) in the ODH- group, with 2 or more disinsertions in 30 eyes (58%) and 5 eyes (10%), respectively. Most hemorrhages and disinsertions were located in the inferotemporal and superotemporal sectors. However, in individual patients, only 33 of the ODHs (39%) were located within a laminar disinsertion. CONCLUSIONS: Laminar disinsertions occurred twice as frequently in eyes with ODHs; however, in individual patients, the spatial concordance between ODHs and laminar disinsertions was poor.