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Introduction: The aim of this study was to compare the long-term outcomes of conventional scleral buckling (CSB), modified scleral buckling (MSB), and scleral encircling (SE) in the treatment of rhegmatogenous retinal detachment and identify factors influencing the outcomes. Methods: This comparative, retrospective cohort study assigned patients to CSB, MSB, and SE groups. The follow-up was 12 months, and the reattachment rate, complication rate, visual acuity, number of newly discovered tears during surgery, and changes in diopters were compared among the three surgeries. Influential factors on anatomical and functional reattachment were identified. Results: There were no significant differences in the primary reattachment rate, overall complication rate, or best corrected visual acuity at 6 or 12 months among the three groups. The MSB group had a higher number of newly discovered tears during surgery compared with the other two groups. At 12 months of post-surgery, the SE group displayed the greatest change of diopter, whereas the MSB group showed the least change. The surgical approach did not influence the primary reattachment rate. Long-term visual outcomes were influenced by factors including sex, preoperative visual acuity, macular status, and duration of symptoms. Conclusion: MSB is an effective method for treating rhegmatogenous retinal detachment. Its advantages include the ability to identify smaller tears and induce minimal changes in diopter. [ABSTRACT FROM AUTHOR]

[Objective] To investigate the chemical constituents from the ethanol extracts of Cynanchum ascyrifolium. [Methods] The compounds were isolated and purified by ODS, macroporous resin chromatography, preparative HPLC methods and so on. Their structures were elucidated by their physical properties, mass spectrometry, and nuclear magnetic resonance spectrum. [Results] Four seco-pregnane-type steroids were isolated from the ethanol extracts of C. ascyrifolium; they were identified to be glaucogenin-A (1), glaucogenin-C 3-0-β-D-theveto-side (2), glaucogenin-C 3-0-β-D-oleandropyranoside (cynatratoside-A, 3), and glaucogenin-A 3-0-β-D-digitoxopyranosyl-(1→4)-β-D-cy-maropyranoside (cynanversicoside F or sublanceoside B2,4). [Conclusions] The four compounds were obtained from C. ascyrifolium for the first time. [ABSTRACT FROM AUTHOR]

ABSTRACT A polyimide (PI) based on benzophenone-3,3′,4,4′-tetracarboxylic acid dianhydride, toluene diisocyanate (TDI), and 4,4′-methylenebis (phenyl isocyanate) (MDI) has been synthesized via a one-step polycondensation procedure. The resulting PI possessed excellent thermal stability with the glass transition temperature ( Tg) 316°C, the 5% weight loss temperature ( T5%) in air and nitrogen 440.4°C and 448.0°C, respectively. The pyrolysis behaviors were investigated with dynamic thermogravimetric analysis (TGA), TGA coupled with Fourier transform infrared spectrometry (TGA-FTIR) and TGA coupled with mass spectrometry (TGA-MS) under air atmosphere. The results of TGA-FTIR and TGA-MS indicated that the main decomposition products were carbon dioxide (CO2), carbonic oxide (CO), water (H2O), ammonia (NH3), nitric oxide (NO), hydrogen cyanide (HCN), benzene (C6H6), and compounds containing NH2, CN, NCO or phenyl groups. The activation energy ( Ea) of the solid-state process was estimated using Ozawa-Flynn-Wall (OFW) method which resulted to be 143.8 and 87.8 kJ/mol for the first and second stage. The pre-exponential factor ( A) and empirical order of decomposition ( n) were determined by Friedman method. The activation energies of different mechanism models were calculated from Coats-Redfern method. Compared with the activation energy values obtained from the OFW method, the actual reaction followed a random nucleation mechanism with the integral form g(α) = −ln(1 − α). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40163. [ABSTRACT FROM AUTHOR]

Purpose: To summarize the causes of retinal arterial microaneurysm combined with branch retinal artery occlusion., Methods: The case reports of retinal arterial microaneurysm combined with branch retinal artery occlusion were searched in PubMed, Web of Science, and CNKI databases before May 1, 2024. A total of nine participants from nine case reports were included to analyze factors leading to complications., Results: The reasons for this complication are as follows: complications during photocoagulation therapy. Intraretinal hemorrhage and exudation result in compression of adjacent or distal arteries, resulting in branch retinal artery occlusion. Embolus dislodgement or intraarterial embolus formation can block the artery, damage the wall, and provide conditions for the development of retinal arterial microaneurysm. In addition, it is necessary to be alert to the optic disk macroaneurysm, if hemorrhage or embolus formation in the macroaneurysm will affect the blood supply of the downstream artery, affecting a large range of the retina., Conclusion: Based on the review of case reports, we found that retinal arterial microaneurysm and branch retinal artery occlusion can cause each other. Acute vision loss can result when a complication occurs. In addition, retinal vascular diseases can reflect the whole body, suggesting that ophthalmologists need to pay attention not only to the patient's fundus but also to the patient's systemic diseases.