In Gram-negative bacteria, lipopolysaccharide transport (Lpt) protein LptA and LptC form a complex to transport LPS from the inner membrane (IM) to the outer membrane (OM). Blocking the interaction between LptA and LptC will lead to the defect of OM and cell death. Therefore, Lpt protein interaction could be used as a target to screen new drugs for killing Gram-negative bacteria. Here we used biolayer interferometry (BLI) assay to detect the interaction between LptA and LptC, with the aim to develop a method for screening the LptA/LptC interaction blockers in vitro. Firstly, LptC and LptA with or without signal peptide (LptAfull or LptAno signal) were expressed in E. coli BL21(DE3). The purified proteins were then labeled with biotin and the super streptavidin (SSA) biosensor was blocked with diluent. The biotin labeled protein sample was mixed with the sensor, and then the binding of the protein with a series of diluted non biotinylated protein was detected. At the same time, non-biotinylated protein was used as a control. The binding of biotinylated protein to a small molecule IMB-881 and the blocking of interaction were also detected by the same method. In the blank control, the biosensor without biotinylated protein was used to detect the serially diluted samples. The signal response constant was calculated by using steady analysis. The results showed that biotinylated LptC had a good binding activity with LptAfull and LptAno signal with KD value 2.9e⁻⁷±7.9e⁻⁸ and 6.0e⁻⁷±2.8e⁻⁸, respectively; biotinylated LptAno signal had a good binding activity with LptC, with a KD value of 9.6e⁻⁷±7.2e⁻⁸. All binding curves showed obvious fast binding and fast dissociation morphology. The small molecule compound IMB-881 can bind to LptA to block the interaction between LptA and LptC, but has no binding activity with LptC. In summary, we developed a method for detecting the LptA/LptC interaction based on the BLI technology, and confirmed that this method can be used to evaluate the blocking activity of small molecule blockers, providing a new approach for the screening of LptA/LptC interaction blockers.
Carrier Proteins ; Escherichia coli/metabolism* ; Escherichia coli Proteins/metabolism* ; Interferometry ; Membrane Proteins/metabolism*

PURPOSE: We investigated the long-term longitudinal changes in axial length (AL), mean ocular perfusion pressure (MOPP), and choroidal thickness (CT) according to the reduction of intraocular pressure (IOP) after glaucoma surgery. The potential variables associated with CT changes were also evaluated.METHODS: This was a prospective study for 1 year after glaucoma surgery, which included 71 eyes of 71 patients with primary open-angle glaucoma. The subfoveal CT (SFCT) and peripapillary CT (PPCT) were measured using spectral-domain optical coherence tomography preoperatively and 1 week, 1 month, 2 months, 6 months, and 1 year postoperatively. MOPP was calculated from the IOP and blood pressure. The AL was measured using partial coherence interferometry. Regression analysis was conducted to assess the possible association of variables.RESULTS: The AL decreased and the MOPP, SFCT, and PPCT increased significantly with IOP reduction at 1 year post-operatively (all, p < 0.001). The changes in SFCT and PPCT were significantly associated with IOP reduction at 1 year postoperatively (r = −0.519 and r = −0.528, respectively). Importantly, greater increases in SFCT and PPCT were found in patients with IOP reduction more than 30% from baseline, when compared with those with less than 30% reduction (p = 0.001 and p = 0.002, respectively). The SFCT increased more significantly in patients with AL ≤ 24 mm, compared with patients with AL > 24 mm (p = 0.044).CONCLUSIONS: Reduction in the IOP, increase in the MOPP, decrease in the AL, and increase in the CT after glaucoma surgery persisted for 1 year during a long-term follow-up. These results suggested that glaucoma surgery reduced mechanical compression on the optic nerve fiber and increased intraocular blood flow.
Blood Pressure ; Choroid ; Follow-Up Studies ; Glaucoma ; Glaucoma, Open-Angle ; Humans ; Interferometry ; Intraocular Pressure ; Optic Nerve ; Perfusion ; Prospective Studies ; Tomography, Optical Coherence

PURPOSE: To evaluate clinical findings in phlyctenular keratoconjunctivitis patients and assess the function and morphology of Meibomian glands using an interferometer (LipiView®, TearScience, Morrisville, NC, USA) in such patients.METHODS: This retrospective study included 19 eyes of 13 patients diagnosed with phlyctenular keratoconjunctivitis. The lipid layer thickness (LLT) and meibograph of each eye was quantified by tear interferometry. Tear film break-up time (TBUT) and corneal staining score were measured. Meibomian gland morphology (lid margin vascularity, plugging of gland orifices, lid margin irregularity, lid margin thickening, and partial glands) was evaluated based on anterior photographs and meibographs.RESULTS: The mean age was 21.3 years (8–44 years). Mean BUT and Oxford corneal staining scores were 2.6 ± 1.2 seconds and 1.9 ± 0.8, respectively. Abnormal findings of the Meibomian glands were observed in all patients. The mean LLT was 79.6 ± 27.4 µm and the incomplete eye blinking frequency was 3.8 ± 5.9 during 20 seconds. The graphs of the tear lipid layer showed various patterns such as flat, up-hill, down-hill, and mixed.CONCLUSIONS: Meibomian gland dysfunctions and changes in the tear film lipid layer were noted in patients with phlyctenular keratoconjunctivitis. These factors are to be considered for the treatment of phlyctenular keratoconjunctivitis in young patients under 10 years of age.
Blinking ; Humans ; Interferometry ; Keratoconjunctivitis ; Meibomian Glands ; Retrospective Studies ; Tears

PURPOSE: To evaluate the changes of axial length (AXL) in eyes with unilateral idiopathic central serous chorioretinopathy (CSC) after resolution of serous retinal detachment. METHODS: A total of 31 patients diagnosed with idiopathic unilateral CSC were included in this study. The changes of AXL according to serous retinal detachment were examined. The keratometric value and AXL were measured using partial coherence interferometry. Serous retinal detachment and central macular thickness (CMT) were measured by spectral domain optical coherence tomography. RESULTS: The mean age of the 31 CSC patients, including 19 males, was 42.7 years. The AXL was significantly increased from 23.41 to 23.58 mm after resolution of serous retinal detachment (p < 0.001). The CMT was significantly decreased from 413.4 to 226.8 µm after resolution of serous retinal detachment (p < 0.001). The differences in AXL correlated with CMT differences and subretinal fluid height (r = −0.616, p < 0.001 and r = −0.637, p < 0.001, respectively), and the best-corrected visual acuity was significantly different after resolution of serous retinal detachment (p < 0.001). CONCLUSIONS: In unilateral idiopathic CSC with serous retinal detachment, a shortened AXL in the acute phase was restored after resolution of serous retinal detachment.
Central Serous Chorioretinopathy ; Humans ; Interferometry ; Male ; Retinal Detachment ; Retinaldehyde ; Subretinal Fluid ; Tomography, Optical Coherence ; Visual Acuity

PURPOSE: The purpose of this study was to derive and compare the inherent color (hue angle, chroma), translucency (TP(SCI)), surface gloss (ΔE* SCE-SCI), and surface roughness (Ra) amongst selected shades and brands of three hybrid CAD/CAM blocks [GC Cerasmart (CS); Lava Ultimate (LU); Vita Enamic (VE)]. MATERIALS AND METHODS: The specimens (N = 225) were prepared into square-shaped (12 × 12 mm2) with different thicknesses and shades. The measurements of color, translucency, and surface gloss were performed by a reflection spectrophotometer. The surface roughness and surface topography were assessed by white light interferometry. RESULTS: Results revealed that hue and chroma values were influenced by the material type, material shade, and material thickness (P < .001). The order of hue angle amongst the materials was LU > CS > VE, whereas the order of chroma was VE > CS > LU. TP(SCI) results demonstrated a significant difference in terms of material types and material thicknesses (P ≤ .001). TP(SCI) values of the tested materials were ordered as LU > CS > VE. ΔE* SCE-SCI and Ra results were significantly varied amongst the materials (P < .001) and amongst the shades (P < .05). The order of ΔE* SCE-SCI amongst the materials were as follows LU > VE ≥ CS, whereas the order of Ra was CS ≥ VE > LU. CONCLUSION: Nano-ceramic and polymer-infiltrated-feldspathic ceramic-network CAD/CAM materials exhibited different optical, inherent color and surface parameters.
Interferometry

PURPOSE: To investigate the change in axial length (AL) in highly myopic adults using partial coherence interferometry, and to identify the factors associated with the increase in AL. METHODS: Medical records of highly myopic adults (≥ −6 diopters [D] or AL ≥ 26.0 mm) were retrospectively reviewed. The AL of each patient was measured using partial coherence interferometry at least three times over 2 years, and the yearly change in AL was calculated. Associations between age, AL, choroidal thickness, and the rate of AL change were evaluated using multiple regression analysis. RESULTS: In total, 24 patients (4 males, 20 females) and 44 eyes were included in this study. The mean age was 54.9 ± 10.4 years, the initial AL was 29.335 ± 2.006 mm, the choroidal thickness was 72.7 ± 41.80 µm, the average spherical equivalent was −11.86 ± 3.85 D (−5.1~−22.0 D), and the mean follow-up period was 2.2 ± 0.5 years. A significant increase in AL of ≥0.05 mm was observed in 38 eyes (86.4%) at 2 years. The mean AL was significantly increased, to 29.409 ± 2.007 mm (p < 0.001), at 1 year and to 29.476 ± 2.028 mm (p < 0.001) at 2 years. The average rate of AL change was 0.071 ± 0.049 mm (−0.01~0.19 mm) per year. None of the included factors showed an association with the rate of AL change in multiple regression analysis. CONCLUSIONS: In this study, an increase in AL in highly myopic adults was more frequent than in previous reports using A-scan. Periodic measurements are therefore recommended for the early detection of complications.
Adult ; Choroid ; Follow-Up Studies ; Humans ; Interferometry ; Male ; Medical Records ; Retrospective Studies

PURPOSE: To validate the possibility of IOLMaster measurement as a predictor of intraoperative and postoperative complications during phacoemulsification surgery. METHODS: In this study, 2,107 eyes from 1,456 patients who underwent phacoemulsification with intraocular lens (IOL) implantation were divided into two groups according to the possibility of performing optical biometry with the IOLMaster (measurable group: 1,746 eyes from 1,141 patients, unmeasurable group: 361 eyes from 315 patients). The intraoperative and postoperative complication rates were compared between the two groups. RESULTS: Three hundred sixty-one eyes (17.1%) could not be measured using optical biometry. Dense posterior subcapsular cataract (56.0%) was the main factor resulting in failed measurements with optical biometry, followed by anterior subcapsular cataract (12.5%). The rates of posterior capsule rupture and radial tear were significantly higher in the unmeasurable group than in the measurable group (p = 0.001, p < 0.001, respectively). Corneal edema was significantly higher in the unmeasurable group (16.1%) than in the measurable group (5.3%) at postoperative 1 week (p < 0.001). CONCLUSIONS: Possibility of optical biometry measurement can be used as a simple predictor of intraoperative and postoperative complications of phacoemulsification surgery. Surgeons should pay close attention to patients who cannot be measured using IOLMaster.
Biometry ; Cataract* ; Corneal Edema ; Humans ; Incidence* ; Interferometry* ; Lenses, Intraocular ; Phacoemulsification ; Postoperative Complications ; Rupture ; Surgeons ; Tears

PURPOSE: To analyze the relationship between ocular surface disease index and tear film lipid layer thickness (LLT) using a LipiView II® (LipiView® Ocular Surface Interferometer, TearScience®, Morrisville, NC, USA) interferometer. METHODS: Forty-nine patients diagnosed with dry eye syndrome were recruited for this prospective study. Patients completed ocular surface disease index questionnaires. We performed slit lamp examination, Schirmer test, corneal and conjunctival fluorescein staining, measured tear film break-up time, and graded meibomian gland dysfunction. Tear LLT, blinking time, and dynamic meibomian imaging were analyzed using a LipiView II® ocular interferometer. To control for missing data, we analyzed four sets of imputated data via the multiple imputation method and performed Pearson correlation analysis. Patients were assigned to one of two LLT categories (LLT < 60 or LLT ≥ 60) and Chi-square test was performed. RESULTS: Among ocular surface disease parameters, tear film break-up time (tBUT) had a statistically significant correlation with average and maximum LLT (average LLT; p = 0.008, 0.035, 0.006, 0.049, maximum LLT; p = 0.006, 0.042, 0.020, 0.049, Pearson correlation analysis with multiple imputation) but there was no significant correlation with minimum LLT (minimum LLT; p = 0.048, 0.090, 0.079, 0.039). Of the patients with a relatively thick average LLT or maximum LLT (LLT ≥ 60 nm), 80% and 88% had a tBUT < 10, respectively. Conversely, 39% and 47% of patients with relatively thin average LLT (LLT < 60 nm) had a tBUT < 10 (average LLT; p = 0.013, maximum LLT; p = 0.039). CONCLUSIONS: Average LLT and maximum LLT were significantly correlated with tBUT. Patients with a relatively thin average or maximum LLT tended to have a shorter tBUT. Based on these results, measuring tear film LLT using a LipiView II® interferometer may be useful in the diagnosis and follow-up of patients with evaporative dry eye.
Blinking ; Diagnosis ; Dry Eye Syndromes ; Fluorescein ; Follow-Up Studies ; Humans ; Interferometry ; Meibomian Glands ; Methods ; Prospective Studies ; Slit Lamp ; Tears*

PURPOSE: To evaluate the changes and characteristics of the anterior segment of the eye after laser peripheral iridotomy (LPI) conducted on patients with acute angle closure crisis (AACC) for both therapeutic purposes and prophylactic purposes in the fellow eye. METHODS: Anterior segments were examined by topography, laser interferometry, anterior segment optical coherence tomography, anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), angle opening distance (AOD), central corneal thickness (CCT), and axial length as compared to prior procedures in 20 eyes with glaucoma (treatment group) and 20 contralateral eyes (prophylactic group) in 20 patients diagnosed with AACC. RESULTS: Before laser treatment, there were no significant differences in pre-LPI ACV, ACA, AOD and axial length, although differences in the CCT and ACD existed between the groups. Compared to prior laser treatment at 1 and 3 months after laser treatment, the ACV, ACA, AOD 500, and AOD 750 increased in both groups. When both groups were compared 1 month after their laser treatments, the AOD 750 was increased in the treatment group. There were no significant differences between two groups 3 months post LPI. CONCLUSIONS: Other than changes in the ACD and CCT, no significant differences were observed in the anterior segment characteristics in AACC affected and contralateral eyes prior to LPI. After LPI, the treatment group showed greater changes in their anterior segments; however, the open angle was maintained at 1 month post treatment.
Anterior Chamber ; Glaucoma ; Glaucoma, Angle-Closure* ; Humans ; Interferometry ; Tomography, Optical Coherence

PURPOSE: To compare the new swept-source optical coherence tomography based IOL Master 700 to both the partial coherence interferometry based IOL Master 500 and ultrasound A-scan in terms of the ocular biometry and the prediction of postoperative refractive outcomes. METHODS: A total 67 eyes of 55 patients who received cataract surgery were included in our study. The axial length, anterior chamber depth, and keratometry were measured using IOL Master 700, IOL Master 500, and A-scan. The predictive errors, which are the differences between predictive refraction and post-operative refraction 1 month after surgery, were also compared. RESULTS: Axial length measurements were not successful in 5 eyes measured using IOL Master 700 and in 12 eyes measured using IOL Master 500. The mean absolute postoperative refraction predictive errors were 0.63 ± 0.50 diopters, 0.66 ± 0.51 diopters, and 0.62 ± 0.51 diopters for IOL Master 700, IOL Master 500, and A-scan, respectively, and these values exhibited no statistically significant differences. The mean axial lengths were 24.25 ± 2.41 mm, 24.24 ± 2.40 mm, and 24.22 ± 2.39 mm; the mean anterior chamber depths were 3.09 ± 0.39 mm, 3.17 ± 0.39 mm, and 3.15 ± 0.46 mm; and the mean keratometry values were 44.12 ± 1.82 diopters, 44.57 ± 2.10 diopters, and 43.98 ± 1.84 diopters for the IOL Master 700, IOL Master 500, and A-scan groups, respectively. None of these parameters showed statistically significant differences between the three groups. Regarding pair-wise comparison, there were significant differences between the IOL Master 700 and the other devices. CONCLUSIONS: The ocular biometric measurements measured using IOL Master 700, IOL Master 500, and A-scan showed no significant differences. However, IOL Master 700 demonstrated a superior ability to successfully take biometric measurements compared to IOL Master 500. Therefore, IOL Master 700 is capable of measuring ocular biometry for cataract surgery in clinical practice.
Anterior Chamber ; Biometry* ; Cataract ; Humans ; Interferometry ; Lenses, Intraocular ; Tomography, Optical Coherence ; Ultrasonography*