Flipped classroom approach to global outreach:cross-cultural teaching of horizontal strabismus to Chinese ophthalmology residents

AIM:To evaluate the flipped classroom model for teaching horizontal strabismus didactics in an ophthalmology residency program in China as part of a visiting professorship from the United States.METHODS:Residents from an ophthalmology residency program in China were invited to participate in flipped classroom sessions taught by an experienced American ophthalmology faculty in 2018.Residents were instructed to watch a pre-class video lecture prior to the in-class-casebased activity.Content tests(5 Ophthalmic Knowledge Assessment Program style questions)and surveys were administered before and after the classroom sessions(100%response rate).These results were compared to that of an American cohort who were taught the same content.RESULTS:The Chinese cohort of 12 residents preferred the flipped classroom to the traditional classroom at higher rates than the American cohort of 40 residents(92%vs 55%,P=0.04)and felt that all ophthalmology topics would be appropriate for the flipped classroom teaching style(P-values between 0.008 and<0.001).In both Chinese and American cohorts,we found that the exotropia curriculum saw a small but significant improvement in performance following the flipped classroom session(P=0.025 for Chinese residents;P=0.001 for US residents),whereas scores in both groups for the esotropia course did not significantly improve.CONCLUSION:This is the first study to evaluate the flipped classroom model implemented by a visiting ophthalmology professor in a global outreach setting.The flipped classroom sessions are viewed favorably by the Chinese residents relative to the US cohort with a modest impact on knowledge.Decreased in-person interpreter requirement and increased student engagement make this model valuable in cross-cultural visiting professorship settings.Finally,the flipped classroom may lend itself well to a virtual format to prevent the transmission of COVID-19,although such a format requires further study.

From structural to functional imaging:the developments of clinical ophthalmology optical coherence tomography

Starting with introduction of basic concept of optical coherence tomography(OCT) techniques,this paper focuses on a detailed review of ophthalmic OCT instruments and their clinical applications. As one of the most important inventions of ophthalmology instruments,OCT has become a standard imaging tool for daily ophthalmic diagnosis. The imaging capability has been significantly improved during the past ~ 30 years. In this article,several representing systems which have made significant contributions to OCT developments will be reviewed in details. For each system,the system configuration will be discussed first,follow ed by a brief introduction of their clinical applications. The review concludes with discussions on potential directions of OCT developments and expectations for further improvements of OCT imaging capabilities.

Advances in teleophthalmology and artificial intelligence for diabetic retinopathy screening:a narrative review

Background and Objective:Advances in teleophthalmology and artificial intelligence(AI)for diabetic retinal screening is of growing public health interest.Currently,only 30–40%of patients with diabetes adhere to recommended diabetes screening guidelines.To enhance early detection and reduce vision threatening complications,there has been a growing number of teleophthalmology programs and novel AI algorithms with the aim to improve eye care access.The purpose of this review is to assess current literature on teleophthalmology and AI for use in diabetic retinopathy(DR)screening,and to discuss advances and barriers to these innovative technologies.Methods:Literature review involving teleophthalmology and AI for DR screening,with focus on the past decade.Key Content and Findings:Teleophthalmology has demonstrated the ability to increase DR screening rates,enable earlier eye care access,and reduce healthcare costs.Novel AI-based DR screening programs appear accurate and effective,but detection of other ocular pathologies is still under development and not yet approved in the United States.Logistical,technological,financial,and legal barriers limit widespread adoption and long-term sustainability of teleophthalmology programs.Conclusions:The use of teleophthalmology and AI algorithms expands eye care access and helps prevent vision loss from DR and potentially other sight threatening conditions.Transparency in the process utilized for arriving at a particular diagnosis or decision to refer,often referred to as the“black box”,remains a multifaceted issue within the field of telemedicine for developing trust and improving patient-centered outcomes.

Apolipoprotein A-I binding protein-mediated neuroprotection in glaucomatous neuroinflammation and neurodegeneration

Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs worldwide.Due to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more prevalent.Glaucoma primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.

Accuracy of biometric formulae for intraocular lens power calculation in a teaching hospital

AIM: To evaluate the accuracy of three commonly used biometric formulae across different axial lengths(ALs) at one United States Veterans Affairs teaching hospital.METHODS: A retrospective chart review was conducted from November 2013 to May 2018. One eye of each patient who underwent cataract surgery with a monofocal intraocular lens(IOL) was included. The range of postoperative follow-up period was from 3 wk to 4 mo. The Holladay 2, Barrett Universal II, and Hill-Radial Basis Function(Hill-RBF) formulae were used to predict the postoperative refraction for all cataract surgeries. For each formula, we calculated the prediction errors [including mean absolute prediction error(MAE)] and the percentage of eyes within ±0.25 diopter(D) and ±0.5 D of predicted refraction. We performed subgroup analyses for short(AL<22.0 mm), medium(AL 22.0-25.0 mm), and long eyes(AL>25.0 mm).RESULTS: A total of 1131 patients were screened, and 909 met the inclusion criteria. Resident ophthalmologists were the primary surgeons in 710(78.1%) cases. We found no statistically significant difference in predictive accuracy among the three formulae over the entire AL range or in the short, medium, and long eye subgroups. Across the entire AL range, the Hill-RBF formula resulted in the lowest MAE(0.384 D) and the highest percentage of eyes with postoperative refraction within ±0.25 D(42.7%) and ±0.5 D(75.5%) of predicted. All three formulae had the highest MAEs(>0.5 D) and lowest percentage within ±0.5 D of predicted refraction(<55%) in short eyes.CONCLUSION: In cataract surgery patients at our teaching hospital, three commonly used biometric formulae demonstrate similar refractive accuracy across all ALs. Short eyes pose the greatest challenge to predicting postoperative refractive error.

Longitudinal observation of intraocular pressure variations with acute altitude changes

BACKGROUND Higher intraocular pressure(IOP)is a major risk factor for developing glaucoma,and the leading cause of irreversible blindness worldwide.High altitude(HA)may be involved in IOP,but the reported results were conflicting.Ascent to HA directly by plane from low altitude regions is an acute,effortless exposure.However,the effects of such exposure to different altitudes on IOP have rarely been reported.AIM To investigate changes in IOP after rapid effortless exposure to HA in stages and compare it with systemic parameters.METHODS Fifty-eight healthy subjects(116 eyes)were divided into three groups:17 lowaltitude(LA)residents[44 m above sea level(ASL)],22 HA residents(2261 m ASL)and 19 very HA(VHA)residents(3750 m ASL).The LA group flew to HA first.Three days later,they flew with the HA group to VHA where both groups stayed for 2 d.Then,the LA group flew back to HA and stayed for 1 d before flying back to 44 m.IOP,oxygen saturation(SpO2)and pulse rate were measured.The linear mixed model was used to compare repeated measurements.RESULTS IOP in the LA group significantly decreased from 18.41±2.40 mmHg at 44 m to 13.60±3.68 mmHg at 2261 m ASL(P<0.001),and then to 11.85±2.48 mmHg at 3750 m ASL(P=0.036 compared to IOP at 2261 m ASL)and partially recovered to 13.47±2.57 mmHg upon return to 44 m.IOP in the LA group at HA and VHA was comparable to that in the local residents(12.2±2.4 mmHg for HA,11.5±1.8 mmHg for VHA).IOP was positively associated with SpO2 while negatively associated with pulse rate.CONCLUSION IOP in the LA group gradually reduced as altitude elevated in stages and became comparable to IOP in local residents.Hypoxia may be associated with IOP,which deserves further study.

Effects of miR-22 on viability,migration,invasion and apoptosis in retinoblastoma Y79 cells by targeting high-mobility group box 1

AIM：To explore the effect of miR-22 on viability,migration,invasion and apoptosis in retinoblastoma（RB）Y79 cells and to further detect the potential mechanism.METHODS：Plasmids were constructed to change the expression level of miR-22 in Y79 cells. Real-time reverse transcription polymerase chain reaction（RT-PCR）was conducted to test the expression level of miR-22. After changing the expression of miR-22,the mRNA and protein levels of high-mobility group box 1（HMGB1） were investigated using RT-PCR and Western blotting.The effect of miR-22 on viability was analyzed by using cell counting kit-8（CCK-8） assay and the effect on apoptosis was detected by the flow cytometry. Wound healing migration assay and Transwell invasion assay were used to detect the effects of miR-22 on cell motility.RESULTS：miR-22 inhibited viability,migration and invasion,while promoting apoptosis,in RB Y79 cells.The inhibition rate of miR-22 overexpression group at 12,24,48h was 11.71%±2.54%,21.36%±1.39% and 29.44%±1.15%,respectively.Cellular apoptosis was higher in miR-22 overexpression group（17.00%±0.39%） compared with negative control（4.38%±0.38%）.miR-22 negatively mediated the expression of HMGB1.Furthermore,decreased

Individuals with and without normal tension glaucoma exhibit comparable performance on tests of cognitive function

AIM:To evaluate aspects of cognition impacted by individuals with and without normal tension glaucoma.METHODS:Fifty normal tension glaucoma(NTG)and 50 control patients≥50 y of age were recruited from the UCSF Department of Ophthalmology.Demographic data and glaucoma parameters were extracted from electronic medical records for both groups.Tests of executive function[Executive Abilities:Measures and Instruments for Neurobehavioral Evaluation and Research(EXAMINER)]and learning and memory[California Verbal Learning Test–Second Edition(CVLT-II)]were administered to both NTG and controls.Race,handedness,best-corrected visual acuity,maximum intraocular pressure,optic nerve cup-todisc ratio,visual field and optic nerve optical coherence tomography parameters,and a measure of general health(Charlson Comorbidity Index)were compared between NTG and controls as well as within NTG subgroups.Multivariate linear regression was used to compare group performances on the EXAMINER battery and CVLT-II while controlling for age,sex,and years of education.RESULTS:NTG and controls were comparable with respect to age,sex,race,education,handedness,and the Charlson Comorbidity Index(P>0.05 for all).Performance on the EXAMINER composite score and the CVLT-II did not differ between NTG and controls(P>0.05 for both).CONCLUSION:This is the first prospective study in which the cognitive function of subject with NTG were evaluated using a comprehensive,computerized neurocognitive battery.Subjects with NTG do not perform worse than unaffected controls on tests of executive function,learning,and memor y.Results do not suppor t the hypothesis that individuals with NTG are at higher risk for cognitive dysfunction and/or dementia.

Long-term outcomes of uveitic glaucoma treated with Ahmed valve implant in a series of Chinese patients

AIM： To report long-term outcomes of secondary glaucoma due to uveitis treated with Ahmed glaucoma valve（AGV） implantation in a series of Chinese patients. METHODS： The retrospective study included 67 eyes from 56 patients with uveitic glaucoma who underwent AGV implantation. Success of the treatment was defined as patients achieving intraocular pressure（IOP） levels between 6 and 21 mm Hg with or without additional antiglaucoma medications and/or a minimum of 20% reduction from baseline IOP. The main outcome measurements included IOP, the number of glaucoma medications at 1, 3, 6, 12, 24, 36, 48 and 60 mo after surgery, surgical complications, final best-corrected vision acuity（BCVA）, visual field（VF） and retinal nerve fiber layer（RNFL）.RESULTS： The mean follow-up was 53.3±8.5（range 48 to 60）mo. The cumulative probability of success rate was 98.5%, 95.5%, 89.6%, 83.6%, 76.1%, 70.1%, 65.7% and 61.2% at 1, 3, 6, 12, 24, 36, 48 and 60 mo, respectively. IOP was reduced from a baseline of 30.8±6.8 to 9.9±4.1, 10.1±4.2, 10.9±3.7, 12.9±4.6, 13.8±3.9, 13.2±4.6, 12.3±3.5 and 13.1±3.7 mm Hg at 1, 3, 6, 12, 24, 36, 48 and 60 mo, respectively（P〈0.01）. The number of postoperative glaucoma medications was significantly decreased compared with baseline at all time points during the study period（P〈0.05）. There was no significant difference between preoperative and postoperative BCVA. Remarkable surgical complications were not found after surgery. The VF and RNFL of the patients were stable after the surgery.CONCLUSION： AGV implantation is safe and effect in terms of reducing IOP, decreasing the number of glaucoma medications, and preserving vision for patients with uveitic glaucoma.

Feasibility of telemedicine program using a hand-held nonmydriatic retinal camera in Panama

AIM: To evaluate the image quality of a telemedicine screening program for retinal disease using a nonmydriatic camera among rural island communities in Bocas del Toro, Panama.METHODS: In June 2018, a group of three medical students volunteered at clinics operated by the Floating Doctors in the province of Bocas del Toro, Panama. Nonmydriatic images of the retina were obtained using the Pictor Plus(Volk Optical, Mentor OH), randomized, and sent to two board-certified ophthalmologists at the University of California, Irvine for analysis using a modified version of the FOTO-ED scale. Inter-rater reliability was calculated using the kappa statistic.RESULTS: Seventy patients provided a total of 127 images. Average image quality was 3.31, and most frequent image quality was 4/5 on the FOTO-ED scale. Thirty patients had at least one eye image with ideal quality(42.86%), while only one patient had no adequate photos taken(1.43%). However, high quality images were obtained in both eyes in only 12 patients(17.14%). The inter-rater reliability between the two ophthalmologists was 0.614.CONCLUSION: Further improvements are necessary to acquire higher quality images more reliably. This may include further training and experience or mydriasis.

Bibliometric analysis of glaucoma-related literature based on SCIE database:a 10-year literature analysis from 2009 to 2018

AIM:To explore the global trends and focus of glaucoma research from 2009 to 2018.METHODS:Searching for glaucoma-related articles published in Science Citation Index Expanded(SCIE)database during 2009-2018,and describing the distribution of the published year,countries,authors,institutions,funding agencies,journals,impact factor,citation and hot research topic of articles by using bibliometric methods.Meanwhile,we compared some of these indicators over two five-year periods,from 2009 to 2013 and from 2014 to 2018.RESULTS:A total of 19609 glaucoma-related articles were retrieved and the global SCIE articles have increased yearly from 2009 to 2018.The USA was the pioneer which has made great contributions.China kept the second place and the number of publications has increased rapidly between 2014 and 2018.The author with the highest number of publications was Weinreb,RN.Co-occurrence maps were built amongst the top 50 authors or the top 50 institutions with the most articles,which visualize the closer collaboration of international authors or institutions.The journal Investigative Ophthalmology&Visual Science has published the most papers.Glaucoma literature with an impact factor of 3-5 points accounted for the largest proportion(28.96%).The most frequently cited paper had 798 citations.The top three hot areas on glaucoma were intraocular pressure,optical coherence tomography(OCT)and retinal ganglion cells.And trabecular meshwork,primary angle-closure glaucoma and Spectral-domain OCT have become new hot research topics in recent five years during 2014-2018.CONCLUSION:Bibliometric analysis is an effective method to describe the global literature on glaucoma.In a 10-year literature survey from 2009 to 2018,global glaucoma research has developed in a balanced manner,and the cooperation between various institutions and teams has become closer.Glaucoma-related pathogenesis research,imaging examinations of OCT and surgery therapy have attracted most attention.

Pediatric neuro-ophthalmology:not simply neuro-ophthalmology for small adults

Pediatric neuro-ophthalmology is a subspecialty within neuro-ophthalmology.Pediatric neuro-ophthalmic diseases must be considered separate from their adult counterparts,due to the distinctive nature of the examination,clinical presentations,and management choices.This manuscript will highlight four common pediatric neuro-ophthalmic disorders by describing common clinical presentations,recommended management,and highlighting recent developments.Diseases discussed include pediatric idiopathic intracranial hypertension(IIH),pseudopapilledema,optic neuritis(ON)and optic pathway gliomas(OPG).The demographics,diagnosis and management of common pediatric neuro-ophthalmic disease require a working knowledge of the current research presented herein.Special attention should be placed on the differences between pediatric and adult entities such that children can be appropriately diagnosed and treated.

The Effect of Anterior Corneal Astigmatism Orientation on Toric Intraocular Lens Outcomes

Background: It is unclear whether post-operative errors after toric intraocular lens implantation would be more amenable to pre-operative correction with a fixed adjustment or a correction ratio that scales with the magnitude of pre-operative astigmatism. Purpose: To investigate the effect of pre-operative anterior corneal astigmatism orientation on outcomes of toric intraocular lens implantation in a large population. Methods: A retrospective cohort study of 625 patients undergoing refractive lens exchange through a superior clear corneal incision with Oculentis M-Plus toric intraocular lens implantation at an Optical Express, Inc. located in the United Kingdom and Ireland. Patients were stratified by axis of astigmatism on automated keratometry as with-the-rule, against-the-rule, or oblique. Analysis of visual acuity and refractive outcomes was performed using American National Standards Institute (ANSI) guidelines on astigmatic corrections with non-vector as well as vector analyses. Analysis was limited to one eye per patient. Results: Patients who had with-the-rule (WTR) astigmatism, compared with oblique and against-the-rule (ATR), had higher vector magnitudes of surgically induced refractive correction (2.89D, 2.55D, 2.42D;p Conclusions: Refractive lens exchange surgery using toric intraocular lenses overcorrected patients who had with-the-rule astigmatism. Degree of overcorrection did not vary with severity of pre-operative astigmatism. Incorporation of axis of astigmatism in lens selection and reduction of astigmatic correction among with-the-rule patients by an absolute value of 0.25D - 0.35D, rather than proportional adjustments, may reduce cylindrical over-correction.

Relationship between contrast sensitivity and corneal shape following overnight orthokeratology

AIM: To evaluate the relationship between contrast sensitivity(CS) and corneal shape following overnight orthokeratology(OK). METHODS: We conducted a retrospective clinical study of 80 lens-wearing myopia patients, all of whom had undergone OK and had been evaluated by Orbscan II topography. We measured the surface irregularity index(SIRI) of corneal topography at 3 and 5 mm, the size of the flattened central corneal curvature of OK lens(zone A), the size of the cornea altered by OK lens(zone B), the size of the pupillary area at the corneal level(zone C), the area of crossover between zones A and C(zone AC), the area of crossover between zones B and C(BC), the ratio of BC to B(BC/B), and the ratio of AC to C(AC/C). CS was evaluated using the CSV-1000 with spatial frequencies of 3, 6, 12, and 18 cycles/degree(CPD). RESULTS: Multiple correlation analyses indicated significant negative correlations between CS, zone C, BC/B, and 3-mm SIRI(all P<0.01). There were no significant differences between CS, zone B, AC/A, or 5-mm SIRI(P=0.60, 0.94 and 0.11, respectively). Zone C was negatively correlated with 3, 6, 12, and 18 CPD. 5-mm SIRI were negatively correlated with 6, 12, and 18 CPD. BC/C was negatively correlated with 6 and 18 CPD. AC/C was positively correlated with 3 CPD. CONCLUSION: Zone C, 3-mm SIRI and BC/B affect the CS following overnight OK.

Clear lens extraction in angle-closure glaucoma patients

AIM: To describe the results of 5 consecutive cases of clear lens extraction in angle closure patients for the treatment of elevated intraocular pressure (IOP). ·METHODS: Retrospective observational case series. All angle closure patients were on two or more topical glaucoma medications and had prior laser iridotomy. Eyes underwent clear lens extraction by phacoemu - lsification with intraocular lens implantation. ·RESULTS: All five patients in this case series carried the diagnosis of angle -closure glaucoma and had uncontrolled IOP prior to surgery despite topical medications. After clear lens extraction three of the cases had good IOP control (IOP 【22mmHg) without the need for topical medications. In one case the IOP was better controlled after surgery, however, topical medications were required. The desired IOP was not met in one case despite restarting maximum topical therapy. ·CONCLUSION: This case series suggests that there may be a role for therapeutic clear lens extraction in select cases of angle-closure glaucoma.

Ultraviolet light exposure and its penetrance through the eye in a porcine model

AIM:To determine the amount of ultraviolet(UV)light irradiance that various layers of the eye receive as sunlight passes through the eye,and to investigate the protective benefits of UV light-blocking contact lenses.METHODS:Twenty-four porcine eyes were prepared in one of three ways:isolated cornea,cornea and lens together,or whole eye preparation.UV light irradiance was measured with a UV-A/B light meter before and after the eye preparations were placed over the meter to measure UV light penetration in each eye structure.In the whole eye preparation,a hole was placed in the fovea to measure light as it passed through the vitreous.Subsequently,UVprotective contact lenses were placed over the structures,and UV light penetrance was measured.Measurements of UV light exposure were taken outdoors at various locations and times.RESULTS:Cornea absorbed 63.56%of UV light that reached the eye.Cornea and lens absorbed 99.34%of UV light.Whole eye absorbed 99.77%of UV light.When UV-protective contact lenses were placed,absorption was 98.90%,99.55%,and 99.87%,respectively.UV light exposure was dependent on directionality and time of day,and was greatest in areas of high albedo that reflect significant amounts of light,such as a beach.CONCLUSION:Cornea absorbs the majority of UV light that reaches the eye in this model.UV-protective contact lenses reduce UV exposure to the eye.Locations with high albedo expose the eye to higher levels of UV light.

cAMP/PKA pathway and mitochondrial protection in oxidative stress-induced optic nerve head astrocytes

Oxidative stress and cyclic adenosine 3′,5′-monophosphate(cAMP)/protein kinase A(PKA)pathway in the optic nerve head astrocytes:Glaucoma is a leading cause of blindness worldwide in individuals 60 years of age and older.Despite the widely appreciated disease relevance of structural and functional abnormalities of astrocyte in the optic nerve head(ONH)that is associated with retinal ganglion cell(RGC)axon degeneration,the molecular mechanisms underlying astrocyte dysfunction in glaucomatous ONH degeneration are poorly understood.Oxidative stress is strongly linked to glaucoma pathogenesis,and astrocytes are the responsible cell type that is mostly related to oxidative stress and glaucomatous ONH degeneration.

白内障摘除术后的急性眼内炎文献的系统回顾

目的：确定白内障摘除术后随时间推移报道的急性眼内炎的发生率并探讨可能引起的因素，如白内障手术切口类型。 方法：以白内障摘除术、眼内炎及术后并发症为关键词，对1963—2003年PubMed上的英文文献进行广泛检索。并进行系统性回顾。附加的研究确认为与其相切题的文献和已发表的会议记录。在可能提供的情况下。记录手术方式。对用不同手术切口技术导致眼内炎发展的累计发生率和相关危险度进行评估。用不同切口的技术评估累计眼内炎的发生率与发展眼内炎的相对危险因素。 结果：从4916篇特定且具潜在相关性的引文中对其中215篇涉及眼内炎且符合入选标准的研究进行分析。总共3140650例白内障手术后，累计0．128％发生眼内炎。然而，急性眼内炎的发生率随着时代不同而改变。与过去lO年相比。2000年以来发生率明显升高（相对危险度，2．44；95％可信区间，2．27—2．61）。2000—2003年眼内炎发生率为0．265％。20世纪90年代为0．087％，80年代为0．158％，70年代为0．327％。并且，与1991年及以前相比，1992年以来发生率有上升趋势。手术切口类型似乎是产生显著影响的危险因素，因为1992—2003年中，经透明角膜切口白内障手术后眼内炎发生率为0．189％。与经巩膜切口0．074％（相对危险度，2．55；95％可信区间，1．75—3．71）及经角巩膜缘切口0．062％（相对危险度，3．06；95％可信区间，2．48—3．76）的发生率相比较，手术切口类型似乎是产生显著影响的危险因素。 结论：这一系统回顾显示，与白内障摘除术相关眼内炎的发生率在过去10年中有所上升。其发生频率的上升趋势与当前无缝线透明角膜白内障摘除术的进展相一致。

泊沙康唑治疗眼眶周围结合菌病(毛霉菌病)

Purpose:To report on the successful treatment of periorbital zygomycosis(mucormycosis)with posaconazole,a broadspectrum oral antifungal available for compassionate use.Design:Interventional case report.Methods:Review of a medical record.Results:A 22-year-old male undergoing induction chemotherapy for acute lymphoblastic leukemia presented with periorbital cellulitis attributable to Rhizopus.The patient was initially treated with liposomal amphotericin B,surgical debridement,and reversal of immune compromise.The patient was switched to posaconazole because of amphotericin side effects and lack of improvement.He took posaconazole for five months while undergoing additional cycles of chemotherapy.Despite recurrent profound neutropenia,the periorbital infection resolved,he tolerated reconstructive procedures,and he did not develop orbital invasion.His Rhizopus isolate was highly susceptible to posaconazole in vitro.Conclusions:Drug toxicities can limit the use of amphotericin in some patients with zygomycosis.Posaconazole shows promise as an alternative antifungal agent in the treatment of periorbital zygomycosis.

对端粒酶永生的角膜上皮细胞系生长和分化的鉴定

PURPOSE. To develop and characterize a telomeraseimm- ortalized human corneal epithelial cell line (hTCEpi) to serve as an in vitro model for studying the molecular mechanisms involved in regulating human corneal epithelial cell differentiation. METHODS. Primary cultures of human corneal epithelial cells were infected with a retroviral vector encoding human telomerase reverse transcriptase (hTERT). Infected hTCEpi cells were selected, cloned, and characterized to identify telomerase activity, proliferative capacity, karyotype, and differentiative potential in routine culture and under consecutive submerged and air- lifted conditions. Cells were evaluated to measure cell cycle kinetics (anti- Ki- 67, anti- p16), stratification (phalloidin and anti- ZO- 1), and differentiation (anti- K3, anti- BCL- 2 and TUNEL labeling). RESULTS. hTCEpi cells exhibited telomerase activity, a normal karyotype and cell cycle kinetics at greater than 240 population doublings, and loss of p16 after passage 10. Air- lifting produced a well stratified epithelium (five to seven cell layers) with apical ZO- 1- stained tight junctions. Submersed culture demonstrated increasing expression of stratification markers (K5/K14) with K3- corneal keratin marker expression in longterm, air- lifted culture. Anti- BCL- 2 staining showed both nuclear and cytoplasmic localization with loss of nuclear BCL- 2 expression in TUNEL- labeled surface epithelial cells. CONCLUSIONS. hTCEpi cells stratify, differentiate, and desquamate similar to normal human corneal epithelium. Further study of the hTCEpi cell line may be valuable in studying the molecularmechanisms regulating corneal epithelial cell differentiation and desquamation.