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1.
Hyperosmotic tear stimulates human corneal nerve endings, activates ocular immune response, and elicits dry-eye symptoms. A soft contact lens (SCL) covers the cornea preventing it from experiencing direct tear evaporation and the resulting blink-periodic salinity increases. For the cornea to experience hyperosmolarity due to tear evaporation, salt must transport across the SCL to the post-lens tear film (PoLTF) bathing the cornea. Consequently, limited salt transport across a SCL potentially protects the ocular surface from hyperosmotic tear. In addition, despite lens-wear discomfort sharing common sensations to dry eye, no correlation is available between measured tear hyperosmolarity and SCL-wear discomfort. Lack of documentation is likely because clinical measurements of tear osmolarity during lens wear do not interrogate the tear osmolarity of the PoLTF that actually overlays the cornea. Rather, tear osmolarity is clinically measured in the tear meniscus. For the first time, we mathematically quantify tear osmolarity in the PoLTF and show that it differs significantly from the clinically measured tear-meniscus osmolarity. We show further that aqueous-deficient dry eye and evaporative dry eye both exacerbate the hyperosmolarity of the PoLTF. Nevertheless, depending on lens salt-transport properties (i.e., diffusivity, partition coefficient, and thickness), a SCL can indeed protect against corneal hyperosmolarity by reducing PoLTF salinity to below that of the ocular surface during no-lens wear. Importantly, PoLTF osmolarity for dry-eye patients can be reduced to that of normal eyes with no-lens wear provided that the lens exhibits a low lens-salt diffusivity. Infrequent blinking increases PoLTF osmolarity consistent with lens-wear discomfort. Judicious design of SCL material salt-transport properties can ameliorate corneal hyperosmolarity. Our results confirm the importance of PoLTF osmolarity during SCL wear and indicate a possible relation between PoLTF osmolarity and contact-lens discomfort. 相似文献
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Glaucoma is a leading cause of irreversible blindness. The use of topical eye drops to reduce intraocular pressure remains the mainstay treatment. These eye drops frequently contain preservatives designed to ensure sterility of the compound. A growing number of clinical and experimental studies report the detrimental effects of not only these preservatives but also the active pharmaceutical compounds on the ocular surface, with resultant tear film instability and dry eye disease. Herein, we critically appraise the published literature exploring the effects of preservatives and pharmaceutical compounds on the ocular surface. 相似文献
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《Transfusion Clinique et Biologique》2022,29(1):94-97
Dynamic monitoring ABO chimera including erythroid ABO antigen and anti-A/B is crucial to not only assess the status of erythroid engraftment but also achieve personalized safety transfusion in patients post ABO incompatible hematopoietic stem cell transplantation. Transfusion support for ABO incompatible (ABOi) HSCT patients after achieved complete alteration to donor origin still remains cautious because the instant hematopoietic status on these transplant patients possibly returned to patient origin derived from early disease relapse and graft loss or failure. We reported that reemergent anti-B in a female patients (donor/patient: B/O) at the early phase after achievement complete donor type were not effectively found from partial automatic ABO blood grouping systems, which directly resulted in differential judgement of transplantation stage for about 15 days and disturbed the optimal recommendation on transfusion support. Meanwhile, the solely alteration of ABO chimera was found and earlier than changes of other markers such as MRD diagnosis, chimerism analysis by STR-PCR and sex chromosome assays, which can be an available predictors for bad transplant outcomes such as graft failure. 相似文献
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《台湾医志》2022,121(12):2490-2500
Background/PurposeOrthokeratology (Ortho-K), atropine eye drops and combined atropine with Ortho-K are proven to be effective ways to prevent myopic progression in many studies, but there is scarce evidence regarding the comparative efficacy of different dosages of atropine,Ortho-K, and combined atropine with Ortho-K for childhood myopia.MethodsWe performed a network meta-analysis (NMA) to assess the relative efficacy of the aforementioned interventions for myopic progression; moreover, we calculated the surface under cumulative ranking area (SUCRA) to determine the relative ranking of treatments.ResultsWe identified 19 randomized controlled trials (3435 patients). NMA revealed that 0.01%–1% atropine, Ortho-K, and 0.01% atropine combined with Ortho-K inhibited axial elongation (AL) over one year. For refractive change, SUCRA analysis revealed that the hierarchy was high-dose (0.5%–1%), moderate-dose (0.1%–0.25%), and low-dose (0.01%–0.05%) atropine. Regarding AL, SUCRA analysis revealed the following hierarchy: Ortho-K combined with 0.01% atropine, high-dose atropine, moderate-dose atropine, Ortho-K, and low-dose atropine.ConclusionIn conclusion, we found that atropine (0.01%–1%), Ortho-K, and 0.01% atropine combined with Ortho-K could significantly slow down myopia progression. The atropine efficacy followed a dose-related pattern; moreover, Ortho-K and low-dose atropine showed similar efficacy. There was a synergistic effect of using 0.01% atropine combined with Ortho-K, and it showed comparable efficacy to that of high-dose atropine. 相似文献
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目的探讨术前眼位注视训练对老年白内障超声乳化摘除术患者术中眼位及术后视力恢复的影响。方法选取2018年9月-2019年9月我院收治的105例老年白内障超声乳化摘除术患者为研究对象,按随机数字表法将其分为对照组52例和试验组53例。对照组给予常规围术期管理。观察组在对照组的基础上予以术前眼位注视训练。观察两组术中眼位情况,术后视力恢复情况及术后并发症发生率。结果试验组术中调整眼位次数>3次和眼球旋转偏移率均低于对照组(P<0.05);试验组术后视力恢复至0.5以上比例为60.38%,高于对照组的40.38%(P<0.05);试验组术后并发症发生率为15.09%,低于对照组的32.69%(P<0.05)。结论老年白内障超声乳化摘除术患者术前进行眼位注视训练,通过降低术中调整眼位次数和眼球旋转偏移率,降低术后并发症发生率,促进患者术后视力恢复。 相似文献
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《Annales de dermatologie et de vénéréologie》2021,148(4):228-232
BackgroundVenous leg ulcers (VLUs) often take a very long time to heal. Timolol maleate has been reported as displaying efficacy in healing of VLUs.ObjectivesTo evaluate the efficacy of timolol maleate gel in the management of hard-to-heal VLUs and to assess its safety as a topical agent during 12 weeks of use in combination with conventional treatment.MethodsA prospective, phase-II randomised-controlled trial with a sample size based on Fleming's one-stage design (P0 = 0.25, P1 = 0.45, alpha = 0.1, beta = 0.2) was planned. Patients with VLUs present for ≥ 24 weeks and with ≥ 50% granulation tissue were included. One drop of sustained-release timolol gel (Timoptol® LP 0.5%, Santen, Tampere, Finland) per 6 cm2 VLU area was applied every 2 days for 12 weeks in timolol-treated patients, as adjuvant therapy to the standard care protocol (interface dressing and multilayer venous compression). Controls received standard care alone. The primary endpoint was to obtain ≥ 40% reduction in ulcer area at week 12 (W12).ResultsForty-three patients were randomised to the study, with 40 receiving at least one treatment and included in the analysis: 21 timolol-treated patients and 19 controls (females: 70%; median age: 72.5 [range 35–93] years). At W12, ≥ 40% ulcer-area reduction was achieved in 14/21 (67%) timolol-treated patients vs. 6/19 (32%) controls. No serious adverse events occurred. Local wound infections not requiring systemic antibiotics occurred in 5 cases in the timolol group and in one case in the controls.ConclusionsThese results support the benefit and safety of using timolol maleate to manage hard-to-heal VLUs, but confirmation is required in a larger multicentre randomised phase-III study. 相似文献