Influencing factors of ocular pain in dry eye disease patients at high altitude

AIM:To quantify the severity and frequency of ocular pain in Tibetan plateau patients with dry eye,and to evaluate the related factors affecting ocular pain.METHODS:A retrospective study included 160 cases of dry eye disease(DED)patients who were treated from July 2022 to June 2023.Age,gender,occupation,illness course,anxiety,plateau duration,plateau protection,ocular surface disease index scale(OSDI),break-up time(BUT),Schirmer I test(SIT),conjunctivitis,history of ophthalmic medication,autoimmune disease,the workload of daily near vision range,smoking and overnight stay were obtained via comprehensive ophthalmic assessment,and their duration was followed up.Logistic regression analysis was used to determine the related factors affecting ocular pain.RESULTS:Totally 77.5%(124/160)of DED patients had ocular pain,of which the severity of ocular pain was mild,moderate,and severe in 30.0%,36.3%,and 11.3%of patients,respectively.Frequency of ocular pain was reported occasional,half the time,frequent,and persistent pain in 19.4%,36.9%,16.9%,and 4.4%.OSDI score was 19.67±5.70(13 to 36),and the level of pain was lowly correlated with OSDI(rs=0.316,P<0.001).Logistic regression showed that in plateau DED patients,increased anxiety led to increased severity and frequency of ocular pain[odds ratio(OR)=3.662,5.613,2.387,and 4.870;all P<0.05],professional eye protection and improvement of daily sleep quantity decreased pain(OR=0.307,0.572,0.418,and 0.789;all P<0.05),while smoking and general protection of plateau did not affect the severity and frequency of ocular pain(all P>0.05).CONCLUSION:Ocular pain is a common complaint in high-altitude DED patients during the pandemic.Anxiety,eye protection,and adequate sleep during the epidemic period are significantly associated with the severity and frequency of ocular pain in patients with plateau DED,while symptoms of DED have relatively little influence on them.

Internal limiting membrane peeling combined with silicone oil or air tamponade for highly myopic foveoschisis

AIM:To compare the efficacy of pars plana vitrectomy(PPV)combined with internal limiting membrane(ILM)and silicone oil or sterile air tamponade for the treatment of myopic foveoschisis(MF)in highly myopic eyes.METHODS:This retrospective study included 48 myopic eyes of 40 patients with MF and axial lengths(ALs)ranging from 26-32 mm treated between January 2020 and January 2022.All patients were underwent PPV combined with ILM peeling followed by sterile air or silicone oil tamponade and followed up at least 12mo.Based on the features on spectral-domain optical coherence tomography(SD-OCT),the eyes were divided into the MF-only group(Group A,n=15 eyes),MF with central foveal detachment group(Group B,n=20 eyes),and MF with lamellar macular hole group(Group C,n=13 eyes).According to AL,eyes were further divided into three groups:Group D(26.01-28.00 mm,n=12 eyes),Group E(28.01-30.00 mm,n=26 eyes),and Group F(30.01-32.00 mm,n=10 eyes).The best-corrected visual acuity(BCVA),central foveal thickness(CFT),and complications were recorded.RESULTS:The patients included 16 males and 24 females with the mean age of 56±9.82y.The BCVA and CFT improved in all groups after surgery(P<0.01),while there was no significant difference of the CFT in Group A,B,and C postoperatively(P>0.05).The intergroup differences of BCVA and CFT postoperatively were statistically significant in Group D,E,and F.Twenty eyes were injected with sterile air,and 28 eyes were injected with silicone oil for tamponade based on the AL.However,there was no statistically significant difference among Groups D,E,and F in terms of the results of sterile air or silicone oil tamponade.The mean recovery time was 5.9mo for MF patients subjected to silicone oil tamponade and 7.7mo for patients subjected to sterile air tamponade,and the difference was not statistically significant.CONCLUSION:PPV and ILM peeling combined with silicone oil or sterile air tamponade can achieve good results for MF in highly myopic eyes with ALs≤32 mm.

Research progress on the correlation between aqueous humor components and pathogenesis and postoperative complications in patients with different types of cataracts

Aqueous humor provides the necessary nutrition for the lens and transports the metabolites in the eye.It was a liquid that can directly reflect the microenvironment in the eye'and it can be easily obtained during the operation.This review intended to analyze the components of aqueous humor in patients with different types of cataracts'so as to reflect the pathogenesis and development of the disease'evaluate the incidence of postoperative complications and provide reference value for the surgical design of sequential cataract surgery.The aqueous humor components of different types of cataracts showed different degrees of inflammation'oxidative stress and extracellular matrix remodeling.The biomarker of early neuropathy in diabetic cataract was neural cell adhesion molecule-1(NCAM1).Transforming growth factor-β(TGF-β)was the evaluation factor of disease development in patients with pseudoexfoliation syndrome.The relationships between postoperative complications of different types of cataracts and aqueous humor components were as follows:Macular edema after diabetic cataract surgery was associated with tumor necrosis factor-alpha;capsular contraction after high myopic cataract surgery was related to monocyte chemoattractant protein-1(MCP-1)and TGF-β2;Klotho and glutathione S-transferase P 1(GSTP1)were associated with high intraocular pressure after primary open-angle glaucoma complicated by cataract surgery;capsular contraction after retinitis pigmentosa complicated by cataract surgery was associated with matrix metalloproteinases;pro-inflammatory cytokines and fibroblast growth factor 4 in the aqueous humor of congenital cataracts were associated with posterior capsular opacification after surgery.Granulocyte colony stimulating factor 3 and MCP-1 were the main cytokines mediating the pain of the second eye in the binocular sequential cataract surgery short interval(1 wk)'while MCP-1 mediated pain in the long interval(6 wk).The second eye after binocular sequential cataract surgery had a higher level of proinflammatory factors.The components of aqueous humor in patients with different types of cataracts were related to the pathogenesis and postoperative complications of the disease.Monitoring the components of the aqueous humor could help better understand the intraocular microenvironment of different types of cataracts and provide a reference for predicting the development of the disease and implementing relevant targeted therapy.

Characteristics of corneal aberration in patients with bilateral keratoconus and unilateral corneal Vogt’s striae

AIM:To assess the corneal high-order aberration(HOA)and its correlation with corneal morphological parameters in patients with bilateral keratoconus(KCN)and unilateral Vogt’s striae.METHODS:A total of 168 eyes of 84 patients with KCN,whose corneas had definite signs of unilateral Vogt’s striae,were enrolled.Corneal HOA and morphological parameters were measured using Pentacam HR.RESULTS:The corneal morphological parameters between KCN eyes with and without Vogt’s striae were evidently different(P<0.001).The 3rd coma 90°,4th spherical aberration,5th coma 90°,root-mean-square(RMS)(total),and RMS(HOA)in the front,back surfaces and total cornea in KCN eyes with Vogt’s striae were significantly higher than those in KCN eyes without Vogt’s striae(P<0.001).In KCN eyes with Vogt’s striae,the 3rd coma 90°and 4th spherical aberration in the front surface and total cornea were negatively correlated with flat keratometry value(K1),steep keratometry value(K2),mean keratometry value(Km),maximum keratometry value(Kmax),anterior corneal elevation(ACE),and posterior corneal elevation(PCE;P<0.05).The 3rd coma 90°,4th spherical aberration in back surface and RMS(total),RMS(HOA)in the front,back surfaces,total cornea were positively correlated with K1,K2,Km,Kmax,ACE,and PCE(P<0.05).CONCLUSION:Corneal HOA especially vertical coma and spherical aberration may increase when Vogt’s striae appeared in KCN eyes.The scale of increase is significantly related with changes in corneal shapes.

Adjustment of IOL power for the second eye based on refractive error of the first-operated eye

This study was to estimate refractive status of the second eye of those undergo bilateral cataract surgery based on the first-operated eye, and to evaluate the refractive error(RE) in the second eye after correcting 50% of the first-operated eye’s error when it exceeded ±0.50 diopter(D). In this prospective study, 80 patients were scheduled for cataract surgery in the second eye, who underwent cataract surgery in first eye 1-3 mo previously. The RE of each eye postoperatively was determined according to SRK/T formula. When the first-eye refractive error(FERE) exceeded ±0.5 D, the intraocular lens(IOL) power of the second eye was adjusted 50% of the FERE. The second-eye refractive error(SERE) was measured 1 mo after surgery. The FERE exceeded-0.50 D in 12 eyes(-0.675±0.16 D), and the adjusted SERE was-0.322±0.73 D(P<0.05). The FERE exceeded +0.50 D in 8 eyes(1.533±1.14 D),and the adjusted SERE was 0.168±1.36 D(P<0.05). The unadjusted SERE in 60 cases remained-0.38 to 0.42 D when the FERE within ±0.05 D. This prospective study confirmed that the prediction of the second eye could be improved by correcting 50% of FERE when this error exceeded ±0.50 D.

Intravitreal slow-release dexamethasone alleviates traumatic proliferative vitreoretinopathy by inhibiting persistent inflammation and Müller cell gliosis in rabbits

AIM:To evaluate the effects of intravitreal slow-release dexamethasone on traumatic proliferative vitreoretinopathy(PVR)and Müller cell gliosis and preliminarily explored the possible inflammatory mechanism in a rabbit model induced by penetrating ocular trauma.METHODS:Traumatic PVR was induced in the right eyes of pigmented rabbits by performing an 8-mm circumferential scleral incision placed 2.5 mm behind the limbus,followed by treatment with a slow-release dexamethasone implant(Ozurdex)or sham injection.Left eyes were used as normal controls.The intraocular pressure(IOP)was monitored using an iCare tonometer.PVR severity was evaluated via anatomical and histopathological examinations every week for 6wk;specific inflammatory cytokine and proliferative marker levels were measured by quantitative real-time polymerase chain reaction,Western blot,protein chip analysis,or immunofluorescence staining.RESULTS:During the observation period,PVR severity gradually increased.Intense Müller cell gliosis was observed in the peripheral retina near the wound and in the whole retina of PVR group.Ozurdex significantly alleviated PVR development and Müller cell gliosis.Post-traumatic inflammation fluctuated and was persistent.The interleukin-1β(IL-1β)mRNA level was significantly upregulated,peaking on day 3 and increasing again on day 21 after injury.The expression of nod-like receptor family pyrin domain containing 3(NLRP3)showed a similar trend that began earlier than that of IL-1βexpression.Ozurdex suppressed the expression of IL-1β,NLRP3,and phosphorylated nuclear factor-kappa B(NF-κB).The average IOP after treatment was within normal limits.CONCLUSION:The present study demonstrates chronic and fluctuating inflammation in a traumatic PVR rabbit model over 6wk.Ozurdex treatment significantly inhibites inflammatory cytokines expression and Müller cell gliosis,and thus alleviates PVR severity.This study highlights the important role of IL-1β,and Ozurdex inhibites inflammation presumably via the NF-κB/NLRP3/IL-1βinflammatory axis.In summary,Ozurdex provides a potential therapeutic option for traumatic PVR.

Astragalin attenuates diabetic cataracts via inhibiting aldose reductase activity in rats

AIM:To investigate the aldose reductase(AR)inhibition capacity of astragalin(AST)against streptozoticin-induced diabetic cataracts(DCs)in rats.METHODS:Ex vivo investigations were conducted by treating the lens of a goat placed for 72h in artificial aqueous humor(AAH)of pH 7.8 at room temperature with cataract-causing substance(55 mmol/L of galactose)and in vivo studies were performed on rats via induction with streptozotocin.AST was administered at different dose levels and scrutinize for DC activity.RESULTS:In diabetic rats,AST improved the body weight,blood insulin,and glucose as well as the levels of galactitol in a dose-dependent way,other biochemical parameters i.e.inflammatory mediators and cytokines,and also suppress AR activity.The level of the antioxidant parameters such as superoxide dismutase(SOD),catalase(CAT),and glutathione(GSH)activity were also altered on a diabetic lens after the administration of the AST.CONCLUSION:AST protects against lens opacification to avoid cataracts and polyols formation,indicating that it could be used as a potential therapeutic agent for diabetes.

Effectiveness of conjunctival bleb scarring by knockdown of heat shock protein 47 in rat model

AIM:To evaluate the effectiveness of knock-down of heat shock protein 47(HSP47)on conjunctival bleb scarring in a rat model and its possible mechanism.METHODS:Male Sprague–Dawley rats were used for glaucoma filtration surgery(GFS)and were treated with either phosphate buffered solution,shControl,mitomycin C,or sh-HSP47 using a microsyringe immediately after GFS.The morphology of filtering blebs was observed postoperatively.The levels of HSP47 were analyzed at 2,5,8,and 11d after GFS via real‑time quantitative polymerase chain reaction(PCR)and Western blot.The silencing effect of HSP47,the expression of collagen I and III,and the potential signaling pathways of HSP47 during scarification were explored 11d post GFS.The protein levels of transforming growth factor-β1(TGF-β1),phospho-Smad2(pSmad2),phospho-Smad3(p-Smad3),and phospho-p38(p-p38)were also analyzed using Western blot.RESULTS:Sh-HSP47 treatment significantly prolonged the functional filtration bleb retention.The levels of HSP47 were increased significantly at 5,8,and 11d postoperatively compared to the control group(P<0.05,P<0.01,and P<0.001).The levels of HSP47 protein at day 11 postoperatively were significantly down-regulated after HSP47 silencing using sh-HSP47 adenovirus transfection(P<0.01).Expression levels of collagen I and III within the blebs were significantly reduced in the absence of HSP47(P<0.01).Moreover,the protein levels of TGF-β1,p-Smad2/3,and p-p38 were dramatically inhibited after treatment with sh-HSP47(P<0.01).CONCLUSION:The inhibitory effects of HSP47 knockdown on scarring after GFS have the potential to be an efficacious therapeutic option for the treatment of conjunctival bleb scarring.

Lipopolysaccharide-induced Trigeminal Ganglion Nerve Fiber Damage is Associated with Autophagy Inhibition

Objective This study aimed to determine whether lipopolysaccharide(LPS)induces the loss of corneal nerve fibers in cultured trigeminal ganglion(TG)cells,and the underlying mechanism of LPS-induced TG neurite damage.Methods TG neurons were isolated from C57BL/6 mice,and the cell viability and purity were maintained for up to 7 days.Then,they were treated with LPS(1µg/mL)or the autophagy regulator(autophibib and rapamycin)alone or in combination for 48 h,and the length of neurites in TG cells was examined by the immunofluorescence staining of the neuron-specific proteinβ3-tubulin.Afterwards,the molecular mechanisms by which LPS induces TG neuron damage were explored.Results The immunofluorescence staining revealed that the average length of neurites in TG cells significantly decreased after LPS treatment.Importantly,LPS induced the impairment of autophagic flux in TG cells,which was evidenced by the increase in the accumulation of LC3 and p62 proteins.The pharmacological inhibition of autophagy by autophinib dramatically reduced the length of TG neurites.However,the rapamycin-induced activation of autophagy significantly lessened the effect of LPS on the degeneration of TG neurites.Conclusion LPS-induced autophagy inhibition contributes to the loss of TG neurites.

Effectiveness of toric soft contact lenses for vision correction in patients with different degrees of astigmatism: a real-world study

AIM:To assess the visual correction of patients with different degrees of astigmatism with toric soft contact lenses(TSC).METHODS:It was a real-world study with prospective and single-arm design.A total of 384 patients with astigmatism who came for TSC fitting and alignment from November 2022 to January 2023 were included.According to the difference in astigmatism,patients were divided into groups A(cylinder degree:-0.75 to-0.50 D),B(cylinder degree:-1.75 to-1.00 D)and C(cylinder degree≤-2.00 D),and followed up on the day of wear,1wk,1 and 3mo,mainly to observe visual acuity,refraction,lens fit,visual quality and comfort at 1wk after wear.The visual acuity success rate and the overall success rate of the fitting were evaluation indicators(taking into account the four dimensions of visual acuity,fitting,quality of vision and comfort).The visual acuity success rate was calculated by taking“corrected visual acuity with contact lenses is no less than 1 line or better than best spectacle-corrected visual acuity”(i.e.corrected visual acuity with contact lenses is 1 line below,equal to,one line above or more than best spectaclecorrected visual acuity)as the criterion for visual success,and the the overall success rate of the fitting was calculated by using the comprehensive indicators(visual acuity,fit,visual quality,comfort)to meet certain conditions as the judgment criteria for successful fitting.RESULTS:After 1wk of wearing TSC,the visual acuity success rates of patients were 100%(207/207),98.58%(139/141)and 97.22%(35/36)in the three groups,respectively,with residual cylinder closed to 0.The acceptability of the lens fitting was over 95%;the incidence of adverse visual symptoms was within 10%and the comfort acceptability was over 97%.The overall success rate of fitting for patients with high,medium and low astigmatism was 93.72%(194/207),90.78%(128/141)and 88.89%(32/36),respectively.CONCLUSION:TSC(model:G&G POP·CT)are effective in correcting astigmatism in patients with different degrees of astigmatism.

Combination of cataract surgery with intravitreal injection of dexamethasone intravitreal implant(Ozurdex)for uveitis-induced cataract

AIM:To evaluate the long-term results of patients with chronic uveitis-induced cataract by phacoemulsification with IOL implantation and intravitreal injection of dexamethasone(DEX)intravitreal implant(Ozurdex).METHODS:The study included 32 eyes of 26 patients treated with DEX implant due to chronic uveitis-induced cataract and followed up for at least a year.Best-corrected visual acuity(BCVA),intraocular pressure(IOP),anterior chamber reaction,central macular thickness(CMT),intraoperative and postoperative complications and uveitis recurrence were analyzed retrospectively.RESULTS:A successful surgery was performed in all patients.The average follow-up period was 12mo.The female/male ratio was 13/13.Mean age was 45.65±3.83y(range 26 to 65y).Etiologically,rheumatic arthritis occurred in 6 patients(18.75%),ankylosing spondylitis in 4(12.50%),HLA-B27 associated uveitis in 3(9.38%),Vogt-KoyanagiHarada-associated uveitis in 4(12.50%),Behcet’s disease in 2(6.25%),and 7(21.88%)suffered from unknown diseases.All 32 eyes had varying degrees of improvement at 12mo after surgery,with 2 eyes showing BCVA of 0.1 or below(6.25%),6 having 0.1-0.5(18.75%),18 of 0.5-1.0(56.25%),and 6 of 1.0 or above(18.75%).No cases with increased IOP were observed.The values of mean CMT was increased at day 1,decreased at 1,3mo after surgery and increased at 6,12mo after surgery.No severe uveitis reactions,such as fibrinous exudates in the anterior chamber and exudative membrane formation on the anterior surface of the IOL,were observed after surgery.CONCLUSION:The present studies show that intravitreal injection of Ozudex during cataract operation can provide a new option for the clinical treatment of uveitis-induced cataract.

Application of femtosecond laser in assisted cataract after ICL implantation with different vault

Dear Editor,We are writing this letter to report two unusual cases of femtosecond laser-assisted cataract surgery(FLACS)in two ICL-implanted patients with significant different vault.FLACS has been confirmed by accumulating evidence to improve the safety and precision of surgery from common cases to complicated cases in treating cataracts[1-3].Implantable collamer lens(ICL)implantation possesses a good performance in its predictability,reversibility,and the rapid visual recovery.

Acute micro-macular hole associating with extensive intraoperative rotation of implantable collamer lens without ophthalmic viscosurgical device assistance:a case report

Dear Editor,We are writing this letter to report a micro-macular hole(mMH)following the intraoperative rotation of implantable collamer lens(ICL,V4c,Staar Surgical,Monrovia,CA,USA)without ophthalmic viscosurgical device(OVD)assistance and eventually this mMH closed spontaneously.

Inflammatory myofibroblastic tumor diagnosed due to high intraocular pressure

Dear Editor,I am writing this letter to present an unusual case of orbital inflammatory myofibroblastic tumor(IMT)diagnosed due to high intraocular pressure(IOP).IMT is a rare mesenchymal,low-grade malignant or borderline tumor,composed of differentiated myofibroblastic spindle cells,often accompanied by plasma cells and lymphocyte infiltration[1].The onset in most patients is insidious.

Evaluation of the long-term effect of foldable capsular vitreous bodies in severe ocular rupture

AIM:To evaluate the long-term effect of foldable capsular vitreous body(FCVB)in the treatment of severe ocular rupture to provide a practical basis for clinical selection.METHODS:A total of 26 patients(26 eyes),23 men and 3 women,with severe ocular rupture who underwent FCVB implantation between March 2018 and September 2018 were retrospectively analysed.All open ocular wounds located in zone III,with preoperative visual acuity grade IV and above(Snellen less than 4/200).The best corrected visual acuity(BCVA),intraocular pressure(IOP),cornea,anterior chamber,iris,lens,choroid,and retina were evaluated before and after the surgery.The subjective feeling and the location of FCVB were also assessed.RESULTS:The average age of the 26 patients was 36y(20-60y).Postoperative follow-up was from 10 to 14mo.At the end of follow up,BCVA was light perception(LP)in 10 cases,no light perception(NLP)in 13 cases,hand motions(HM)in 3 cases.IOP was 11±5 mm Hg.Corneal degeneration was in 3 cases and corneal endothelial dystrophy was in 7 cases.Shallow anterior chamber was in 8 cases and hyphema was in 8 cases.Organized membrane in the pupil was in 14 cases.Epiphora occurred in 3 cases.FCVB drainage tube exposed in 3 cases.All FCVBs were in their normal location and no rejection occurred.CONCLUSION:FCVB implantation is a long-term effective treatment and may provide a practical selection for severe ocular rupture.

Comparative analysis of visual quality between unilateral implantation of a trifocal intraocular lens and a rotationally asymmetric refractive multifocal intraocular lens

·AIM:To compare visual quality after unilateral cataract surgery with implantation of trifocal intraocular lens(IOL)and asymmetric refractive multifocal IOL.·METHODS:The prospective nonrandom,comparative study consisted of 60 eyes of 60 patients suffering unilateral cataract surgery with implantation of two different IOLs:AT LISA tri 839 MP(30 eyes;Carl Zeiss Meditec,Germany)and LS-313 MF30(30 eyes;Oculentis GmbH,Germany).Visual acuity,refractive outcome,contrast sensitivity,defocus curves,quality of vision,and optical phenomena were evaluated at3 mo postoperatively.·RESULTS:There were no statistical differences between groups in uncorrected distance visual acuity(P=0.13)and uncorrected near visual acuity(P=0.54).In contrast,uncorrected intermediate visual acuity was better in trifocal group compared to the refractive multifocal group(P=0.02).No significant statistical between-group difference was detected in cylinder(P=0.43).Compared to trifocal group,spherical refraction and spherical equivalent in refractive multi focal group were more myopic(P<0.01).Under photopic conditions,no significant statistical differences were found between groups in contrast sensitivity at 3 and 6 cycles per degree(cpd).The refractive multifocal group performed better at 12 and 18 cpd than the trifocal group(P=0.01,P=0.034,respectively).The questionnaires of quality of vision and optical phenomena showed no differences between groups.·CONCLUSION:Trifocal IOL is superior to refractive multifocal IOL in intermediate visual acuity.Rotationally asymmetric refractive multifocal IOL is more myopic in automated refraction and significantly better for the photopic contrast sensitivity at high frequency.

Establishment of an acute extraocular muscle injury model in cats

AIM： To describe an acute extraocular muscle injury model in cats. METHODS： Seventy-two cats were randomly divided into 6 groups（12 cats per group）. Cats＇ left lateral recti were clamped using a surgical needle holder with a clamping strength of 2（Groups A and D）, 4（Groups B and E） and 6 kg（Groups C and F）. The right lateral recti were treated as controls. On the 4^（th） and 7^（th） days, hematoxylin eosin（HE） staining, immunohistochemical staining for proliferating cell nuclear antigen（PCNA）, muscle force measurements and ocular alignment changes were performed to evaluate the extent of injuries. RESULTS： The morphological changes were graded as mild, moderate or severe by HE staining in all experiment groups. PCNA immunohistochemical staining indicated repairment of muscle fibers in the damaged area. On the 4^（th） and 7^（th） days after clamping, the injured lateral muscle exhibited an elevated threshold for electric stimulation. The muscle forces among groups 2, 4 and 6 kg injury at 4 d（Groups A, B and C） were statistically significant（P0.05）, respectively. In addition, medial deviation in ocular alignment was also present to various degrees in all groups. CONCLUSION： A cat model of acute extraocular muscle injury can be established by rectus clamping. Different clamping strengths can make different degrees of muscle injury. This model may help the future study in the acute extraocular muscle injury.

Supercontinuum fiber laser-based coherent anti-Stokes Raman scattering microscopy for label-free chemical imaging

Coherent anti-Stokes Raman scattering(CA RS)microscopy can resolve the chemical compo-nents and distribution of living biological systems in a label-firee manner and is favored in several disciplines.Current CA RS microscopes typically use bulky,high-performance solid-state lasers,which are expensive and sensitive to environmental changes.With their relatively low cost and environmental sensitivity,supercontinum fiber(SF)lasers with a small footprint have found increasing use in biomedical applications.Upon these features,in this paper,we homebuilt a low-cost CARS microscope based on a SF laser module(scCA RS microscope).This SF laser module is specially customized by adding a time synchronized seed source channel to the SF laser to form a dual-channel output laser.The performance of the scCARS microscope is evaluated with dimethyl sulfoxide,whose results confirm a spatial resolution of better than 500nm and a detection sensitivity of millimolar concentrations.The dual-color imaging capability is further demonstrated by imaging different species of mixed microspheres.We finally explore the potential of our scCARS microscope by mapping lipid droplets in different cancer cells and corneal stromal lenses.

Characterization of and advanced diagnostic methods for ocular tuberculosis and tuberculosis

Tuberculosis(TB)is an airborne infection caused by Mycobacterium tuberculosis that usually affects the lungs.Timely treatment of active TB,diagnosis and prevention of latent TB are very important.However,extrapulmonary TB affects almost any tissues around the eye and orbit,and it then requires a high degree of suspicion to accurately diagnose.Diagnostic delays are common and may lead to morbidity.For ophthalmologists and infectious disease specialists,it is important to work together to accurately diagnose and treat ocular tuberculosis(OTB)to prevent vision loss.This review reports the latest advanced diagnostic methods for active TB and latent TB as well as various known manifestations of 0TB.Important elements of diagnosis and treatment are also reviewed.

A Trojan horse biomimetic delivery system using mesenchymal stem cells for HIF-1α siRNA-loaded nanoparticles on retinal pigment epithelial cells under hypoxia environment

AIM: To demonstrate the feasibility of mesenchymal stem cell(MSC)-mediated nano drug delivery, which was characterized by the “Trojan horse”-like transport of hypoxiainducible factor-1α small interfering RNA(HIF-1α si RNA) between MSCs and retinal pigment epithelial cells(RPE) under hypoxia environment.METHODS: Plasmid and lentivirus targeting the human HIF-1α gene were designed and constructed. HIF-1α si RNA was encapsulated into poly(lactic-co-glycolic acid) nanoparticles(PLGA-NPs) through the water-in-oil-in-water(w/o/w) multiple emulsion technique. The effect of PLGANPs uptake on the expression of HIF-1α m RNA was tested in RPE cells by real-time quantitative polymerase chain reaction(q PCR) and additional transfected conditions were used as control, including lentivirus group, nude plasmid group and blank PLGA group. MSCs were transfected with the NPs and the transfection efficacy was evaluated by flow cytometry. Transwell co-culture system of transfected MSCs and RPE cells was constructed under hypoxia environment. The effects of MSC-loaded HIF-1α si RNA PLGA-NPs on proliferation, apoptosis, and migration of RPE cells were then evaluated. The effect of transfected MSCs on HIF-1α expression of RPE cells was analyzed by using q PCR at the time points 24h, 3d, and 7d.RESULTS: The average diameter of PLGA-NPs loaded with HIF si RNA was 314.1 nm and the zeta potential was-0.36 m V. The transfection efficiency of PLGA-NPs was 67.3%±5.2% into MSCs by using flow cytometry. Compared with the lentivirus group, the PLGA-NPs loaded with HIF-1α si RNA can effectively reduce the expression of HIF-1α m RNA up to 7d in RPE(0.63±0.05 at 7d, P<0.001). In the Transwell co-culture system of transfected MSCs and RPE, the abilities of proliferation(2.34±0.17, 2.40±0.28, 2.47±0.24 at 48h, F=0.23, P=0.80), apoptosis(14.83%±2.43%, 12.94%±2.19%, 12.39%±3.21%;F=0.70, P=0.53) and migration(124.5±7.78, 119.5±5.32, 130±9.89, F=1.33, P=0.33) of the RPE cells had no differences between MSCloaded HIF-1α si RNA PLGA-NPs and other groups. The inhibition of PLGA on the HIF-1α m RNA expression in RPE cells could continue until the 7th day, the level of HIF-1α m RNA was lower than that of other groups(F=171.98, P<0.001). CONCLUSION: The delivery of PLGA-NPs loaded with HIF-1α si RNA carried by MSCs is found to be beneficial temporally for HIF-1α m RNA inhibition in RPE cells under hypoxia environment. The MSC-based bio-mimetic delivery of HIF-1α si RNA nanoparticles is a potential method for therapy against choroidal neovascularization.