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Objective To evaluate the effectiveness of intense pulsed light (IPL) therapy for meibomian gland dysfunction (MGD).Methods A prospective senal cases observational study was designed.Thirty patients with MGD (60 eyes)in the Tianjin Medical University Eye Hospital from October 2017 to April 2018 were enrolled.All the subjects received IPL therapy at baseline,1 week and 3 weeks after the baseline,respectively.Before each treatment and 3 months after treatment,subjective symptoms (ocular surface disease index [OSDI] questionnaire,Standard Patient Evaluation of Eye Dryness [SPEED] questionnaire),palpebral margin score,lipiview ocular surface interferometer lipid layer thickness (LLT) measurement,tear meniscus height (TMH) and noninvasive tear film breakup time (NIBUT) measurement were performed to detect and assess the IPL treatment effect.The safety of the IPL treatment was evaluated through the visual acuity and intraocular pressure.Results The OSDI score,SPEED score and the score of lipid excretion and secretion of meibomian gland before treatment were significantly higher than those of the other three time points (all at P＜0.01).The TMH before treatment was significantly lower than that of the other three time points (all at P＜0.01).No significant differences were obtained on first time NIBUT,blinking times and incomplete blink ratio among different time points (all at P＞0.05).After treatment,the average thickness of tear film lipid layer was slightly increased,and the secretion of tarsal gland was improved.There were no adverse reactions during the treatment and follow-up,no changes in corrected vision,and the intraocular pressure fluctuated within the normal range.Conclusions IPL therapy can alleviate the symptoms and signs of dry eye of MGD patients,and the effect can last for at least 3 months.IPL is an effective and safe method in treatment of MGD.
RESUMO
Hepatitis B surface antigen (HBsAg) subvirus particles produced from yeast share immunological determinants with mature viruses, which enable the use of HBsAg as a potent antigen for human vaccination. Because the intimate structure of such pseudoviral particles is still a matter of debate, we investigated the robustness of the external barrier and its structure and dynamics using the noninvasive solid-state NMR technique. This barrier is made of 60% proteins and 40% lipids. Phospholipids represent 83% of all lipids, and chain unsaturation is of 72%. Dynamics was reported by embedding small amounts of deuterium chain-labeled unsaturated phospholipid into the external barrier of entire subviral particles, while controlling particle integrity by cryoelectron microscopy, tomography, and light scattering. Variable preparation modes were used, from mild incubation of small unilamellar vesicles to very stringent incorporation with freeze-drying. A lipid bilayer structure of 4- to 5-nm thickness was evidenced with a higher rigidity than that of synthetic phospholipid vesicles, but nonetheless reflecting a fluid membrane (50-52% of maximum rigidity) in agreement with the elevated unsaturation content. The HBsAg particles of 20- to 24-nm diameter were surprisingly found resistant to lyophilization, in such a way that trapped water inside particles could not be removed. These dual properties bring more insight into the mode of action of native subviral particles and their recombinant counterparts used in vaccines.
