Journal articles: 'Lens'

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Kurosaka, Daijiro, Toshiyasu Imaizumi, and Junya Kizawa. "Time Course of Lens Epithelial Cell Behavior in Rabbit Eyes following Lens Extraction and Implantation of Intraocular Lens." Journal of Ophthalmology 2021 (January 16, 2021): 1–8. http://dx.doi.org/10.1155/2021/6659838.

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Background. After cataract surgery, some lens epithelial cells (LECs) transdifferentiate into myofibroblast-like cells, which causes fibric posterior capsule opacification (PCO). Residual LECs differentiate into lens fiber cells, forming Elschnig pearls with PCO. This study was carried out to identify the time course of both types of LEC behavior in rabbit eyes following lens extraction and implantation of an intraocular lens (IOL). Methods. Phacoemulsification and implantation of posterior chamber IOLs were performed in rabbit eyes. Following enucleation, immunohistochemical methods were used to detect α-smooth muscle actin (α-SMA), a marker for myofibroblast-like cells, in the pseudophakic rabbit eyes. A mouse monoclonal antibody against α-SMA was used. Results. Soon after the operation, the LECs migrated and covered the lens capsule. Thereafter, the LECs around the anterior capsular margin were always positive for α-SMA. However, the distributions of these cells were not consistent. In some specimens, α-SMA-positive LECs were present around the IOL optic early after surgery, but most of them had disappeared several weeks after the surgery. The residual cells induced fibrotic PCO. In the other specimens, most LECs around the IOL optic except the anterior capsular margin were negative for α-SMA. In the peripheral region covered by the peripheral anterior and posterior capsules, LECs on the posterior capsule always differentiated into lens fiber cells and formed a Soemmering ring. Thereafter, migration of lens fiber cells from the Soemmering ring and differentiation of LECs in situ on the central posterior capsule consisted of Elschnig pearls type of PCO. Conclusions. Although postoperative LEC behavior is not consistent, residual α-SMA-positive LECs induced fibrotic PCO. The lens fiber cells that migrated from the peripheral capsular bag or that were differentiated in situ covered the central posterior capsule, forming Elschnig pearls with PCO.

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Novo, Samuel G., Adam P. Faranda, Mahbubul H. Shihan, Yan Wang, Ananya Garg, and Melinda K. Duncan. "The Immediate Early Response of Lens Epithelial Cells to Lens Injury." Cells 11, no. 21 (November 1, 2022): 3456. http://dx.doi.org/10.3390/cells11213456.

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Cataracts are treated by lens fiber cell removal followed by intraocular lens (IOL) implantation into the lens capsule. While effective, this procedure leaves behind numerous lens epithelial cells (LECs) which undergo a wound healing response that frequently leads to posterior capsular opacification (PCO). In order to elucidate the acute response of LECs to lens fiber cell removal which models cataract surgery (post cataract surgery, PCS), RNA-seq was conducted on LECs derived from wild type mice at 0 and 6 h PCS. This analysis found that LECs upregulate the expression of numerous proinflammatory cytokines and profibrotic regulators by 6 h PCS suggesting rapid priming of pathways leading to inflammation and fibrosis PCS. LECs also highly upregulate the expression of numerous immediate early transcription factors (IETFs) by 6 h PCS and immunolocalization found elevated levels of these proteins by 3 h PCS, and this was preceded by the phosphorylation of ERK1/2 in injured LECs. Egr1 and FosB were among the highest expressed of these factors and qRT-PCR revealed that they also upregulate in explanted mouse lens epithelia suggesting potential roles in the LEC injury response. Analysis of lenses lacking either Egr1 or FosB revealed that both genes may regulate a portion of the acute LEC injury response, although neither gene was essential for expression of either proinflammatory or fibrotic markers at later times PCS suggesting that IETFs may work in concert to mediate the LEC injury response following cataract surgery.

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Taqwim, Moh Ahsanit, Imam Sucahyo, and Meta Yantidewi. "RANCANG BANGUN ALAT PENENTU PANJANG FOKUS PADA LENSA BIKONVEKS MENGGUNAKAN SENSOR TEMT6000 DAN MOTOR STEPPER." Inovasi Fisika Indonesia 10, no. 2 (July 5, 2021): 81–86. http://dx.doi.org/10.26740/ifi.v10n2.p81-86.

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Abstrak Penelitian ini bertujuan untuk merancang instrumen pengukuran panjang fokus lensa bikonveks secara otomatis. Dengan menerapkan sifat lensa bikonveks dimana berkas-berkas sinar yang paralel terhadap sumbu lensa akan dibiaskan dan berpotongan pada titik fokus. Titik fokus lensa ditentukan menggunakan sensor TEMT6000 dan panjang fokusnya diukur meggunakan motor stepper. Sinar dari dua buah laser dioda yang dipasang sejajar terhadap sumbu lensa akan berpotongan pada titik fokus sehingga intensitas di titik tersebut akan maksimum. Sensor TEMT6000 yang terhubung dengan motor stepper bergerak linier sesumbu dengan sumbu lensa dan berhenti pada titik fokus lensa karena hasil pembacaan sensor bernilai maksimum pada titik tersebut. Mikrokontroler akan menghitung jarak yang ditempuh sensor dan menampilkannya pada display sebagai panjang fokus lensa. Instrumen ini akan diujicobakan pada tiga buah lensa yang memiliki spesifikasi panjang fokus 100 mm, 150 mm, 200 mm, 250 mm dan 300 mm. Berdasarkan penelitian yang dilakukan, panjang fokus hasil pengukuran secara otomatis adalah: 103,8 mm untuk lensa berspesifikasi panjang fokus 100 mm dengan tingkat kesalahan 3,8%, 153,1 mm untuk lensa berspesifikasi panjang fokus 150 mm dengan tingkat kesalahan 2,1%, 203,2 mm untuk lensa berspesifikasi panjang fokus 200 mm dengan tingkat kesalahan 1,6%, 253,2 mm untuk lensa berspesifikasi panjang fokus 250 mm dengan tingkat kesalahan 1,3%, 303,5 mm untuk lensa berspesifikasi panjang fokus 300 mm dengan tingkat kesalahan 1,1%. Penyebab terjadinya penyimpangan titik fokus adalah berkas sinar yang berasal dari laser tidak sejajar dengan sumbu lensa dikarenakan terjadi penyimpangan sudut tembak laser. Kata Kunci: panjang fokus lensa bikonveks, sensor TEMT6000, motor stepper Abstract This study aims to design an automatic instrument for measuring the focal length of biconvex lens. By applying the property of a biconvex lens, the rays parralel to the axis of the lens will be refracted and intersect at the focal point. The focal point of the lens was determined using a TEMT6000 sensor and the focal length measured using a stepper motor. The rays from the two laser diodes that were placed parallel to the lens axis would intersect at the focal point so that the intensity at that point would be maximum. TEMT6000 sensor which is connected to the stepper motor moves linearly about the lens axis and stops at the focal point of the lens because the sensor reading is maximum at that point. Microcontroller would calculate the distance travelled by the sensor and show it on the display as the focal length of the lens. The instrument would be tested on five lenses that have focal length specifications of 100 mm, 150 mm, 200 mm, 250 mm and 300 mm. Based on the research wich has been done, focal length of the automatic measurement results is: 103,8 mm for the lens with the specification of focal length 100 mm and the error was 3,8%, 153,1 mm for the lens with the specification of focal length 150 mm and the error percentage is 2,1%, 203,2 mm for the lens with the specification of focal length 200 mm and the error percentage was 1,6%, 253,2 mm for the lens with the specification of focal length 250 mm and the error percentage was 1,3%, 303,5 mm for the lens with the specification of focal length 300 mm and the error percentage was 1,1%. The cause of focal point deviation is, ray from the laser was not parallel to the lens axis due to laser beam angle deviation. Keywords: focal length of biconvex lens, TEMT6000 sensor, stepper motor

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Xiong, Lang, Yan Sun, Jingqi Huang, Pengjuan Ma, Xiaoran Wang, Jiani Wang, Baoxin Chen, et al. "Long Non-Coding RNA H19 Prevents Lens Fibrosis through Maintaining Lens Epithelial Cell Phenotypes." Cells 11, no. 16 (August 17, 2022): 2559. http://dx.doi.org/10.3390/cells11162559.

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The integrity of lens epithelial cells (LECs) lays the foundation for lens function and transparency. By contrast, epithelial-mesenchymal transition (EMT) of LECs leads to lens fibrosis, such as anterior subcapsular cataracts (ASC) and fibrotic forms of posterior capsule opacification (PCO). However, the underlying mechanisms remain unclear. Here, we aimed to explore the role of long non-coding RNA (lncRNA) H19 in regulating TGF-β2-induced EMT during lens fibrosis, revealing a novel lncRNA-based regulatory mechanism. In this work, we identified that lncRNA H19 was highly expressed in LECs, but downregulated by exposure to TGF-β2. In both human lens epithelial explants and SRA01/04 cells, knockdown of H19 aggravated TGF-β2-induced EMT, while overexpressing H19 partially reversed EMT and restored lens epithelial phenotypes. Semi-in vivo whole lens culture and H19 knockout mice demonstrated the indispensable role of H19 in sustaining lens clarity through maintaining LEC features. Bioinformatic analyses further implied a potential H19-centered regulatory mechanism via Smad-dependent pathways, confirmed by in vitro experiments. In conclusion, we uncovered a novel role of H19 in inhibiting TGF-β2-induced EMT of the lens by suppressing Smad-dependent signaling, providing potential therapeutic targets for treating lens fibrosis.

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Andjelic, Sofija, and Marko Hawlina. "Human Primary Lens Epithelial Cultures on Basal Laminas Studied by Synchrotron-Based FTIR Microspectroscopy for Understanding Posterior Capsular Opacification." International Journal of Molecular Sciences 25, no. 16 (August 14, 2024): 8858. http://dx.doi.org/10.3390/ijms25168858.

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Human primary lens epithelial cultures serve as an in vitro model for posterior capsular opacification (PCO) formation. PCO occurs when residual lens epithelial cells (LECs) migrate and proliferate after cataract surgery, differentiating into fibroblastic and lens fiber-like cells. This study aims to show and compare the bio-macromolecular profiles of primary LEC cultures and postoperative lens epithelia LECs on basal laminas (bls), while also analyzing bls and cultured LECs separately. Using synchrotron radiation-based Fourier transform infrared (SR-FTIR) (Bruker, Karlsruhe, Germany) microspectroscopy at the Spanish synchrotron light source ALBA, we observed that the SR-FTIR measurements were predominantly influenced by the strong collagen absorbance of the bls. Cultured LECs on bls showed a higher collagen contribution, indicated by higher vas CH3, CH2 and CH3 wagging and deformation, and the C–N stretching of collagen. In contrast, postoperative LECs on bls showed a higher cell contribution, indicated by the vsym CH2 peak and the ratio between vas CH2 and vas CH3 peaks. The primary difference revealed using SR-FTIR is the greater LEC contribution in spectra recorded from postoperative lens epithelia compared to cultured LECs on bls. IR spectra for bl, cultured LECs and postoperative lens epithelia could be valuable for future research.

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Syu, Yong-Sin, and Yung-Chun Lee. "Quantitative Evaluation of Light Collimating for Commercial UV-LEDs Based on Analytic Collimating Lens." Applied Sciences 12, no. 2 (January 17, 2022): 911. http://dx.doi.org/10.3390/app12020911.

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This paper proposes a lens design method for effectively collimating the light emitting from a light-emitting diode (LED). This collimating lens contains two aspherical lens surfaces which can be mathematically characterized using a few designing parameters, and hence is called an analytic collimating lens. An optical ray-tracing algorithm has been developed for these analytic collimating lenses to analyze their optical performance and to optimize their designs. Six high-power and commercially available ultraviolet (UV) LEDs are chosen as examples for demonstrating the optimal collimating lens design. For each UV-LED, the corresponding optical collimating lens is determined by inputting the ray data file provided by the manufacture over a finite-size emitting area. The divergent angles of the six UV-LEDs have been successfully collimated to a narrow range in between 1.56° to 2.84° from their original radiation angle around 46° to 120°. Furthermore, the proposed analytical collimating lenses are suitable for mass-production using standard mold injection methods, and hence possess great potentials for industry applications of LEDs.

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Zhang, Junfang, Jiawei Luo, Guowei Zhang, Bai Qin, Xiumei Ren, and Huaijin Guan. "An Ex Vivo Study on Release, Uptake, and miRNA Profile of Exosomes in Rat Lens." Journal of Ophthalmology 2022 (April 21, 2022): 1–7. http://dx.doi.org/10.1155/2022/6706172.

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Purpose. To identify the ability of releasing and uptaking exosomes in rat lens and characterize the exosomal microRNA profile of lens-derived exosomes. Methods. The rat lenses were cultured ex vivo and the medium was collected. The exosomes were isolated from medium and measured in size and concentration by nanoflow cytometry (nFCM) and transmission electron microscopy (TEM) and verified with CD63 and TSG101 by Western blot. The miRNAs in exosomes released from lens epithelial cells (LECs) were sequenced. The plasma exosomes labeled by PKH26 were used to verify the exosomes uptake LECs, and their colocalized fluorescence was imaged by confocal microscopy. Results. LECs released numerous exosomes into the medium through the capsule, which contained abundant miRNAs. The most abundant miRNAs included miR-184, let-7c-5p, let-7a-5p, let-7b-5p, let-7f-5p, miR-125a-5p, miR-204-5p, miR-125b-5p, miR-1b, and miR-23a-3p. The LECs but not the lens fibre cells showed exosome uptake. The LECs uptake more PKH26-labeled exosomes at day 7 than day 3 and day 14. Conclusions. Our results suggested that LECs can release and uptake exosomes through the capsule. Exosomes may be an important way for the lens to communicate among LECs, aqueous humour, vitreous body, and other ocular tissues.

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Yoon, Min-Hwa. "Changes of Refractive Correction Value with Different Age Group: A Case for Myopia Control Lens, Single Vision Lens and Reverse Geometry Contact Lens." Journal of Korean Ophthalmic Optics Society 18, no. 1 (March 31, 2013): 75–84. http://dx.doi.org/10.14479/jkoos.2013.18.1.075.

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Taiyab, Aftab, Yasmine Belahlou, Vanessa Wong, Saranya Pandi, Madhu Shekhar, Gowri Priya Chidambaranathan, and Judith West-Mays. "Understanding the Role of Yes-Associated Protein (YAP) Signaling in the Transformation of Lens Epithelial Cells (EMT) and Fibrosis." Biomolecules 13, no. 12 (December 9, 2023): 1767. http://dx.doi.org/10.3390/biom13121767.

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Fibrotic cataracts, posterior capsular opacification (PCO), and anterior subcapsular cataracts (ASC) are mainly attributed to the transforming growth factor-β (TGFβ)-induced epithelial-to-mesenchymal transition (EMT) of lens epithelial cells (LECs). Previous investigations from our laboratory have shown the novel role of non-canonical TGFβ signaling in the progression of EMT in LECs. In this study, we have identified YAP as a critical signaling molecule involved in lens fibrosis. The observed increase in nuclear YAP in capsules of human ASC patients points toward the involvement of YAP in lens fibrosis. In addition, the immunohistochemical (IHC) analyses on ocular sections from mice that overexpress TGFβ in the lens (TGFβtg) showed a co-expression of YAP and α-SMA in the fibrotic plaques when compared to wild-type littermate lenses, which do not. The incubation of rat lens explants with verteporfin, a YAP inhibitor, prevented a TGFβ-induced fiber-like phenotype, α-SMA, and fibronectin expression, as well as delocalization of E-cadherin and β-catenin. Finally, LECs co-incubated with TGFβ and YAP inhibitor did not exhibit an induction in matrix metalloproteinase 2 compared to those LECs treated with TGFβ alone. In conclusion, these data demonstrate that YAP is required for TGFβ-mediated lens EMT and fibrosis.

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Shen, Xinyue, Manhui Zhu, Lihua Kang, Yuanyuan Tu, Lele Li, Rutan Zhang, Bai Qin, Mei Yang, and Huaijin Guan. "Lanosterol Synthase Pathway Alleviates Lens Opacity in Age-Related Cortical Cataract." Journal of Ophthalmology 2018 (July 11, 2018): 1–9. http://dx.doi.org/10.1155/2018/4125893.

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Purpose. Lanosterol synthase (LSS) abnormity contributes to lens opacity in rats, mice, dogs, and human congenital cataract development. This study examined whether LSS pathway has a role in different subtypes of age-related cataract (ARC). Methods. A total of 390 patients with ARC and 88 age-matched non-ARC patients were enrolled in this study. LSS expression was analyzed by western blot and enzyme-linked immunosorbent assay (ELISA). To further examine the function of LSS, we used U18666A, an LSS inhibitor in rat lens culture system. Results. In lens epithelial cells (LECs), LSS expression in LECs increased with opaque degree C II, while it decreased with opaque degree C IV and C V. While in the cortex of age-related cortical cataract (ARCC), LSS expression was negatively related to opaque degree, while lanosterol level was positively correlated to opaque degree. No obvious change in both LSS and lanosterol level was found in either LECs or the cortex of age-related nuclear cataract (ARNC) and age-related posterior subcapsular cataract (ARPSC). In vitro, inhibiting LSS activity induced rat lens opacity and lanosterol effectively delayed the occurrence of lens opacity. Conclusions. This study indicated that LSS and lanosterol were localized in the lens of human ARC, including ARCC, ARNC, and ARPSC. LSS and lanosterol level are only correlated with opaque degree of ARCC. Furthermore, activated LSS pathway in lens is protective for lens transparency in cortical cataract.

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Mukmin, Amrul, Parjiman, and Muhamad Rif’an. "PENGARUH PENGGUNAAN LENSA DIVERGEN SERTA KONVERGEN TERHADAP DAYA KELUARAN PANEL SURYA." Journal of Electrical Vocational Education and Technology 1, no. 2 (March 21, 2020): 44–51. http://dx.doi.org/10.21009/jevet.0012.08.

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ABSTRACT The purpose of this research is to increase the power output of the solar panels and to know the effect on the solar panel after adding a converging lens and a diverging treatment varying distances and angles. The hypothesis of this study is anticipated to the influence of the use of a diverging lens and converges to the power output of solar panels. This study used an experimental method with quantitative approach. The subjects of the study were used that kind of Polycrystalline solar panels. Data analysis technique used is descriptive analysis with data collection techniques are observation laboratory and field observations. The conclusion of this study is to raise the value of the output power on solar panels can use a converging lens. This is evidenced by the results of the testing are the biggest increase in the converging lens use solar panels to power 900 outputs the angle and the distance between the lens and solar panels with a power output of 25 cm measured 56.46 μW. The influence of the use of a converging lens located on the corner of 150 and the distance between the lens and the solar panel 21 cm with an increase of 203.64%. These values occurred as a converging lens can focus the light so that the intensity of the light falling on the solar panels increases. While the greatest influence use of a diverging lens located on the corner of 300 and the distance between the lens and solar panels 1 cm with a decrease of 63.96%. These values occurred as a diverging lens can refract light so that the intensity of the light falling on the solar panel decreases. ABSTRAK Tujuan penelitian ini yaitu untuk meningkatkan daya keluaran pada panel surya dan untuk mengetahui perbedaan pengaruh pada panel surya setelah ditambahkan lensa konvergen serta divergen dengan perlakuan jarak dan sudut yang bervariasi. Hipotesis penelitian ini yaitu diduga adanya pengaruh dari penggunaan lensa divergen dan konvergen terhadap daya keluaran panel surya. Penelitian ini menggunakan metode eksperimen dengan pendekatan kuantitatif. Subyek penelitian yang digunakan yaitu panel surya jenis Polycrystalline. Teknik analisis data yang digunakan yaitu analisis deskriptif dengan teknik pengumpulan data yaitu observasi laboratorium dan observasi lapangan. Kesimpulan dari penelitian ini yaitu Untuk menaikan nilai daya keluaran pada panel surya dapat menggunakan lensa konvergen. Hal ini dibuktikan dengan hasil pengujian terdapat kenaikan terbesar penggunaan lensa konvergen pada panel surya terhadap daya keluaran yaitu sudut 900 dan jarak antara lensa dan panel surya 25 cm dengan daya keluaran yang terukur 56,46 µW.Pengaruh terbesar penggunaan lensa konvergen terdapat pada sudut 150 dan jarak antara lensa dan panel surya 21 cm dengan kenaikan sebesar 203,64%. Nilai tersebut terjadi karena lensa konvergen dapat memusatkan cahaya sehingga intensitas cahaya yang jatuh pada panel surya meningkat. Sedangkan pengaruh terbesar penggunaan lensa divergen terdapat pada sudut 300 dan jarak antara lensa dan panel surya 1 cm dengan penurunan sebesar 63,96%. Nilai tersebut terjadi karena lensa divergen dapat membiaskan cahaya sehingga intensitas cahaya yang jatuh pada panel surya menurun. jatuh pada panel surya menurun.

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Ruan, Xiaoting, Zhenzhen Liu, Lixia Luo, and Yizhi Liu. "The Structure of the Lens and Its Associations with the Visual Quality." BMJ Open Ophthalmology 5, no. 1 (September 2020): e000459. http://dx.doi.org/10.1136/bmjophth-2020-000459.

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In humans, the lens is the organ with the ability to change morphology and refractive power, designated as accommodation, to focus light from various distances and obtain clear retinal image. The accommodative ability of the lens depends on its structure and biological parameters. The lens grows throughout the life, forming specific lens sutures and a unique gradient refractive index, and possesses regenerative ability under certain circumstances. Minimally invasive lens surgery that preserves endogenous lens epithelial stem/progenitor cells (LECs) can achieve functional lens regeneration in humans. The lens is the main source of intraocular aberration, especially intraocular higher-order aberrations (IHOAs) which is found to be binocularly symmetrical in phakic eyes. There is a compensation mechanism between corneal aberrations and lens aberrations. Therefore, the structure and the biological parameters of the lens, the binocular relationship of the lens and the correlation between the lens and cornea affect visual quality. This paper summarises the above findings and their current and potential applications in refractive surgeries, providing a comprehensive understanding of the lens as a strong determinant of visual quality in the optical system.

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Shibata, Shinsuke, Naoko Shibata, Satoshi Ohtsuka, Yasuo Yoshitomi, Etsuko Kiyokawa, Hideto Yonekura, Dhirendra P. Singh, Hiroshi Sasaki, and Eri Kubo. "Role of Decorin in Posterior Capsule Opacification and Eye Lens Development." Cells 10, no. 4 (April 9, 2021): 863. http://dx.doi.org/10.3390/cells10040863.

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Decorin (DCN) is involved in a variety of physiological and pathological processes. Epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs) has been proposed as a major cause for the development of posterior capsule opacification (PCO) after cataract surgery. We investigated the plausible target gene(s) that suppress PCO. The expression of Dcn was significantly upregulated in rat PCO tissues compared to that observed in the control using a microarray-based approach. LECs treated with fibroblast growth factor (FGF) 2 displayed an enhanced level of DCN expression, while LECs treated with transforming growth factor (TGF)β-2 showed a decrease in DCN expression. The expression of tropomyosin 1 (Tpm1), a marker of lens EMT increased after the addition of TGFβ-2 in human LEC; however, upregulation of Tpm1 mRNA or protein expression was reduced in human LECs overexpressing human DCN (hDCN). No phenotypic changes were observed in the lenses of 8- and 48-week-old transgenic mice for lens-specific hDCN (hDCN-Tg). Injury-induced EMT of the mouse lens, and the expression patterns of α smooth muscle actin, were attenuated in hDCN-Tg mice lenses. Overexpression of DCN inhibited the TGFβ-2-induced upregulation of Tpm1 and EMT observed during wound healing of the lens, but it did not affect mouse lens morphology until 48 weeks of age. Our findings demonstrate that DCN plays a significant role in regulating EMT formation of LECs and PCO, and suggest that for therapeutic intervention, maintenance of physiological expression of DCN is essential to attenuate EMT progression and PCO formation.

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Zhang, Rong-Pei, and Zheng-Gao Xie. "Research Progress of Drug Prophylaxis for Lens Capsule Opacification after Cataract Surgery." Journal of Ophthalmology 2020 (July 4, 2020): 1–9. http://dx.doi.org/10.1155/2020/2181685.

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Phacoemulsification combined with intraocular lens (IOL) implantation is the international standard operation procedure for cataract and has been generalized worldwide. However, lens capsule opacification, one of the common complications after cataract surgery, impacts the recovery of patients’ visual function to a large extent. Lens capsule opacification has two types, anterior capsule opacification (ACO) and posterior capsule opacification (PCO), according to the location. There is not an accepted approach to treat ACO. Nd : YAG laser capsulotomy, the common treatment of PCO, can effectively improve the vision, but may cause a series of complications and is inappropriate for children who are too young to cooperate with this treatment. It is generally known that the responses of lens epithelial cells (LECs) after cataract surgery, including cell proliferation, migration, and epithelial-mesenchymal transition (EMT), play a key role in the pathogenesis of lens capsule opacification. Scholars found that substantial drugs can reduce the occurrence of lens capsule opacification by inhibiting, clearing, or killing LECs, and made great efforts as well as innovations on the exploration of drug species or modes of administration. This article is a systematic interpretation and elaboration about how to prevent lens capsule opacification after cataract surgery via different drugs.

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Yang, Qing, Siyu Tong, Feng Chen, Zefang Deng, Hao Bian, Guangqing Du, Jiale Yong, and Xun Hou. "Lens-on-lens microstructures." Optics Letters 40, no. 22 (November 10, 2015): 5359. http://dx.doi.org/10.1364/ol.40.005359.

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Kubo, Eri, Teppei Shibata, Dhirendra Singh, and Hiroshi Sasaki. "Roles of TGF β and FGF Signals in the Lens: Tropomyosin Regulation for Posterior Capsule Opacity." International Journal of Molecular Sciences 19, no. 10 (October 9, 2018): 3093. http://dx.doi.org/10.3390/ijms19103093.

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Transforming growth factor (TGF) β and fibroblast growth factor (FGF) 2 are related to the development of posterior capsule opacification (PCO) after lens extraction surgery and other processes of epithelial–mesenchymal transition (EMT). Oxidative stress seems to activate TGF β1 largely through reactive oxygen species (ROS) production, which in turn alters the transcription of several survival genes, including lens epithelium-cell derived growth factor (LEDGF). Higher ROS levels attenuate LEDGF function, leading to down-regulation of peroxiredoxin 6 (Prdx6). TGF β is regulated by ROS in Prdx6 knock-out lens epithelial cells (LECs) and induces the up-regulation of tropomyosins (Tpms) 1/2, and EMT of LECs. Mouse and rat PCO are accompanied by elevated expression of Tpm2. Further, the expression of Tpm1/2 is induced by TGF β2 in LECs. Importantly, we previously showed that TGF β2 and FGF2 play regulatory roles in LECs in a contrasting manner. An injury-induced EMT of a mouse lens as a PCO model was attenuated in the absence of Tpm2. In this review, we present findings regarding the roles of TGF β and FGF2 in the differential regulation of EMT in the lens. Tpms may be associated with TGF β2- and FGF2-related EMT and PCO development.

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Markiewicz, Ewa, Stephen Barnard, Jackie Haines, Margaret Coster, Orry van Geel, Weiju Wu, Shane Richards, et al. "Nonlinear ionizing radiation-induced changes in eye lens cell proliferation, cyclin D1 expression and lens shape." Open Biology 5, no. 4 (April 2015): 150011. http://dx.doi.org/10.1098/rsob.150011.

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Elevated cataract risk after radiation exposure was established soon after the discovery of X-rays in 1895. Today, increased cataract incidence among medical imaging practitioners and after nuclear incidents has highlighted how little is still understood about the biological responses of the lens to low-dose ionizing radiation (IR). Here, we show for the first time that in mice, lens epithelial cells (LECs) in the peripheral region repair DNA double strand breaks (DSB) after exposure to 20 and 100 mGy more slowly compared with circulating blood lymphocytes, as demonstrated by counts of γH2AX foci in cell nuclei. LECs in the central region repaired DSBs faster than either LECs in the lens periphery or lymphocytes. Although DSB markers (γH2AX, 53BP1 and RAD51) in both lens regions showed linear dose responses at the 1 h timepoint, nonlinear responses were observed in lenses for EdU (5-ethynyl-2′-deoxy-uridine) incorporation, cyclin D1 staining and cell density after 24 h at 100 and 250 mGy. After 10 months, the lens aspect ratio was also altered, an indicator of the consequences of the altered cell proliferation and cell density changes. A best-fit model demonstrated a dose-response peak at 500 mGy. These data identify specific nonlinear biological responses to low (less than 1000 mGy) dose IR-induced DNA damage in the lens epithelium.

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Ishida, Hidetoshi, Teppei Shibata, Yuka Nakamura, Yasuhito Ishigaki, Dhirendra P. Singh, Hiroshi Sasaki, and Eri Kubo. "Identification of Differential Gene Expression Pattern in Lens Epithelial Cells Derived from Cataractous and Noncataractous Lenses of Shumiya Cataract Rat." BioMed Research International 2020 (November 2, 2020): 1–9. http://dx.doi.org/10.1155/2020/7319590.

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The Shumiya cataract rat (SCR) is a model for hereditary cataract. Two-thirds of these rats develop lens opacity within 10-11 weeks. Onset of cataract is attributed to the synergetic effect of lanosterol synthase (Lss) and farnesyl-diphosphate farnesyltransferase 1 (Fdft1) mutant alleles that lead to cholesterol deficiency in the lenses, which in turn adversely affects lens biology including the growth and differentiation of lens epithelial cells (LECs). Nevertheless, the molecular events and changes in gene expression associated with the onset of lens opacity in SCR are poorly understood. In the present study, a microarray-based approach was employed to analyze comparative gene expression changes in LECs isolated from the precataractous and cataractous stages of lenses of 5-week-old SCRs. The changes in gene expression observed in microarray results in the LECs were further validated using real-time reverse transcribed quantitative PCR (RT-qPCR) in 5-, 8-, and 10-week-old SCRs. A mild posterior and cortical opacity was observed in 5-week-old rats. Expressions of approximately 100 genes, including the major intrinsic protein of the lens fiber (Mip and Aquaporin 0), deoxyribonuclease II beta (Dnase2B), heat shock protein B1 (HspB1), and crystallin γ (γCry) B, C, and F, were found to be significantly downregulated (0.07-0.5-fold) in rat LECs derived from cataract lenses compared to that in noncataractous lenses (control). Thus, our study was aimed at identifying the gene expression patterns during cataract formation in SCRs, which may be responsible for cataractogenesis in SCR. We proposed that cataracts in SCR are associated with reduced expression of these lens genes that have been reported to be related with lens fiber differentiation. Our findings may have wider implications in understanding the effect of cholesterol deficiency and the role of cholesterol-lowering therapeutics on cataractogenesis.

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Zhu, L., A. Ge, Z. Ge, R. Hao, J. Chen, and X. Tao. "A Fresnel freeform surface collimating lens for LEDs." Lighting Research & Technology 50, no. 6 (June 6, 2017): 952–60. http://dx.doi.org/10.1177/1477153517712780.

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This paper proposes a freeform surface lens design based on the Fresnel model to achieve a compact structure and good collimation. A simulation indicates the lens enjoys an efficiency as high as 88.43% within a half view angle of 2° for 1 × 1 mm2 size LED. This paper makes a comparison of three types of lens, among which the Fresnel freeform lens achieves the best performance when the LED size is smaller than 2.5 × 2.5 mm2. The influence of the LED size and the manufacturing tolerances are discussed.

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Joo, Jae Young, Chang Suk Kang, Soon Sub Park, and Sun Kyu Lee. "Fabrication of a Beam Shaping Lens for Chip Scale Packaged LEDs." Key Engineering Materials 447-448 (September 2010): 101–5. http://dx.doi.org/10.4028/www.scientific.net/kem.447-448.101.

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In this paper, we demonstrated the machining process of a novel Light Emitting Diodes (LED) beam shaping lens, called TIR Fresnel lens, for GaN-based blue Chip Scale Packaged (CSP) LEDs. Upon achieving a precise alignment of the tool and identifying the best manufacturing condition, we have successfully fabricated a prototype of this lens on poly methyl methacrylate (PMMA) plate. The form error of the central aspheric lens was less than 1 μm deviation, and surface quality of the Fresnel facets were sufficient for Total Internal refraction without any burr or adhesion of the machined chip. Fabricated TIR Fresnel lens reduced the viewing angle of the testing CSP LED from 140° to 17.4° in FWHM. The proposed lens produced extreme compactness as well as high collimation efficiency, thereby applicable to an ultra-thin optical system.

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Park, Byoung Guk, Kiwoon Choi, Chul Jin Jo, and Han Sup Lee. "Micro lens-on-lens array." Soft Matter 8, no. 6 (2012): 1751–55. http://dx.doi.org/10.1039/c2sm06988a.

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Smith, Warren J. "Lens design and lens designers." Optics News 14, no. 6 (June 1, 1988): 29. http://dx.doi.org/10.1364/on.14.6.000029.

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Syu, Yong-Sin, Chun-Ying Wu, and Yung-Chun Lee. "Double-Sided Freeform Lens for Light Collimation of Light Emitting Diodes." Applied Sciences 9, no. 24 (December 12, 2019): 5452. http://dx.doi.org/10.3390/app9245452.

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A double-sided freeform lens is proposed for collimating light emitted from light emitting diodes (LEDs). The surface profiles of the lens are mathematically characterized and precisely determined based on a point-source assumption and differential geometry theory. The proposed lens design method is straightforward, flexible, and effective. Moreover, the optical performance of the lens can be intuitively adjusted by tuning just a small number of design parameters. The simulation results showed that the proposed lens achieved an excellent collimating effect for a commercial ultraviolet (UV) LED. A prototype lens is fabricated in UV-grade poly(methyl methacrylate) material using a standard injection molding process. The light collimating effect of the lens/UV-LED assembly was measured experimentally and was shown to be in good agreement with the simulation results. The collimating angle at the half-energy level was equal to 1.88°. The performance of the UV-LED is thus comparable to that of conventional lithography UV light sources based on mercury arc lamps. Consequently, the proposed double freeform lens showed significant potential for photolithography applications within the industry.

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Joveini, F., and M. Akbari. "SCHWARZ PROBLEM IN LENS AND HALF LENS." Eurasian Mathematical Journal 10, no. 2 (2019): 49–64. http://dx.doi.org/10.32523/2077-9879-2019-10-2-49-64.

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Binkhorst, C. D. "The Lens Capsule and the Intraocular Lens-the ‘Moustache Lens’." European Journal of Implant and Refractive Surgery 1, no. 1 (March 1989): 62–64. http://dx.doi.org/10.1016/s0955-3681(89)80040-1.

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Azarifar, Mohammad, Ceren Cengiz, and Mehmet Arik. "Optical and Thermal Analysis of Secondary Optics in Light Emitting Diodes’ Packaging: Analysis of MR16 Lamp." Journal of Physics: Conference Series 2116, no. 1 (November 1, 2021): 012121. http://dx.doi.org/10.1088/1742-6596/2116/1/012121.

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Abstract Optical and thermal control are two main factors in package design process of lighting products, specifically light emitting diodes (LEDs). This research is aimed to study the role of secondary optics in opto-thermal characterization of LED packages. Novel thin total internal reflection (TIR) multifaceted reflector (MR) lens is modelled and optimized in Monte-Carlo ray-tracing simulations for MR16 package, regarded as one of the widely used LED lighting products. With criteria of designing an optical lens with 50% reduced thickness in comparison to commercially available lenses utilized in MR16 packages, nearly same light extraction efficiency and more uniform beam angles are achieved. Optical performance of the new lens is compared with the experimental results of the MR16 lamp with conventional lens. Only 2.3% reduction in maximum light intensity is obtained while lens size reduction was more than 25%. Based on the detailed CAD design, heat transfer simulations are performed comparing the lens thickness effect on heat dissipation of MR16 lamp. It was observed that using thinner lenses can reduce the lens and chip temperature, which can result in improved light quality and lifetime of both lens and light source.

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Chao, Paul C. P., Lun De Liao, Chi Wei Chiu, and Chien Yu Shen. "Enhancement of the Optical Performances for the LED Backlight Systems with a Novel Dual Lens-Cap." Key Engineering Materials 364-366 (December 2007): 132–37. http://dx.doi.org/10.4028/www.scientific.net/kem.364-366.132.

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A novel dual-cone-shaped side-emitting lens cap for High Brightness Light Emitting Diodes (HB-LEDs) is proposed for improving brightness and high uniformity of the direct LED backlight Units (BLUs) for large-sized LCD-TVs. Combining the designed lens cap with red, green and blue (RGB) chips on a Metal Core Printed Circuit Board (MCPCB), the LED module with the proposed cap is able to provide a compact white light source with unique features such as instant color variability and lower power usage, etc. The dual-cone-shaped of the proposed lens cap is designed to emit most of the light rays to the sides, only a small portion of light upward along the optical axis of the lens, providing a uniform luminance distribution and the high brightness on the backlight. In addition, a small reflective surface in semi-circular shape is designed and placed upon the proposed LED module about 10mm, the surfaces of which are attached with reflective films to increase the level of light mixing in the larger, global reflector optical box. With the structure of the LED module well designed, the LED backlight Module would be designed for the large-sized LCDTV using the fewer number of LEDs to lead to lower power consumption. The results indeed identify the attributes of the BLU, which make it possible to achieve excellent backlight performance using a direct illumination approach from the light source of “Dual-Cone-Shaped Side- Emitting Lens Cap of LEDs.”

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Amelia, Wulan Rizky, Vonna Riasari, Raihanah Suzan, Erny Kusdiyah, and Gita Mayani. "HUBUNGAN PENGGUNAAN LENSA KONTAK DENGAN DERAJAT KEPARAHAN DRY EYE SYNDROME PADA SISWA KELAS XI SMA NEGERI DI KECAMATAN TELANAIPURA, KOTA JAMBI JANUARI-MARET 2021." Electronic Journal Scientific of Environmental Health And Disease 2, no. 2 (December 1, 2021): 94–105. http://dx.doi.org/10.22437/esehad.v2i2.16913.

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ABSTRACT Background: Dry eye syndrome is a high incidence multifactorial tear condition.The use of contact lense have been reported that it would have a high risk to get dry eye syndrome for people who often use contact lense. To see the relationship between contact lens use and the severity of dry eye syndrome in class XI SMA N Telanaipura District, Jambi City January-March 2021. Methods: This study is an observational analytic study with a cross sectional approach with a simple random sampling technique. Results: Through the OSDI questionnaire and Schirmer, it was found that the moderate degree had the MOST number. Through the fisher test, the relationship between dry eye syndrome severity and gender based on the OSDI questionnaire p-value = 0.001, contact lens replacement time = 0.016, contact lens use period = 0.019, purpose of wearing contact lenses = 0.158. Based on Schirmer, the correlation between dry eye syndrome severity and gender p-value = 0.054, contact lens replacement time = 0.223, contact lens use period = 0.368, intended contact lens wear = 0.740. Conclusion: There is a significant relationship between the use of contact lenses with the severity of dry eye syndrome in senior high school students class XI Telanaipura District, Jambi City from January to March 2021 based on the OSDI questionnaire. Keyword: Dry Eye Syndrome, contact lenses, OSDI questionnaire, Schirmer's test. ABSTRAK Latar Belakang: Dry eye syndrome merupakan kondisi multifaktorial air mata yang berinsidensi tinggi. Penggunaan lensa kontak telah sering dilaporkan memliki resiko lebih tinggi untuk mengalami dry eye syndrome. Tujuan Penelitian: Untuk mengetahui hubungan penggunaan lensa kontak dengan derajat keparahan dry eye syndrome siswa kelas XI SMA N Kecamatan Telanaipura, Kota Jambi Januari-Maret 2021. Metode : Penelitian ini merupakan penelitian analitik observasional dengan pendekatan cross sectional dengan tekhnik pengambilan sampel simple random sampling. Hasil: Melalui kuisioner OSDI dan schirmer didapat derajat sedang memiliki jumlah terbanyak. Melalui uji fisherdidapat hubungan derajat keparahan dry eye syndrome dengan jenis kelamin berdasarkan kuisioner OSDI p-value = 0,001, waktu penggantian lensa kontak= 0,016, masa penggunaan lensa kontak = 0,019, tujuan pemakaian lensa kontak = 0,158. Berdasarkan schirmer, didapat hubungan derajat keparahan dry eye syndrome dengan jenis kelamin p-value = 0,054, waktu penggantian lensa kontak = 0,223, masa penggunaan lensa kontak = 0,368, tujuan pemakaian lensa kontak = 0,740. Kesimpulan : Terdapat hubungan signifikan antara penggunaan lensa kontak dengan derajat keparahan dry eye syndrome siswa kelas XI SMA N Kecamatan Telanaipura, Kota Jambi Januari-Maret 2021 berdasarkan kuisioner OSDI. Kata Kunci: Dry Eye Syndrome, lensa kontak, Kuisioner OSDI, Tes Schirmer.

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Flokis, Mary, and Frank J. Lovicu. "FGF-2 Differentially Regulates Lens Epithelial Cell Behaviour during TGF-β-Induced EMT." Cells 12, no. 6 (March 7, 2023): 827. http://dx.doi.org/10.3390/cells12060827.

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Fibroblast growth factor (FGF) and transforming growth factor-beta (TGF-β) can regulate and/or dysregulate lens epithelial cell (LEC) behaviour, including proliferation, fibre differentiation, and epithelial–mesenchymal transition (EMT). Earlier studies have investigated the crosstalk between FGF and TGF-β in dictating lens cell fate, that appears to be dose dependent. Here, we tested the hypothesis that a fibre-differentiating dose of FGF differentially regulates the behaviour of lens epithelial cells undergoing TGF-β-induced EMT. Postnatal 21-day-old rat lens epithelial explants were treated with a fibre-differentiating dose of FGF-2 (200 ng/mL) and/or TGF-β2 (50 pg/mL) over a 7-day culture period. We compared central LECs (CLECs) and peripheral LECs (PLECs) using immunolabelling for changes in markers for EMT (α-SMA), lens fibre differentiation (β-crystallin), epithelial cell adhesion (β-catenin), and the cytoskeleton (alpha-tropomyosin), as well as Smad2/3- and MAPK/ERK1/2-signalling. Lens epithelial explants cotreated with FGF-2 and TGF-β2 exhibited a differential response, with CLECs undergoing EMT while PLECs favoured more of a lens fibre differentiation response, compared to the TGF-β-only-treated explants where all cells in the explants underwent EMT. The CLECs cotreated with FGF and TGF-β immunolabelled for α-SMA, with minimal β-crystallin, whereas the PLECs demonstrated strong β-crystallin reactivity and little α-SMA. Interestingly, compared to the TGF-β-only-treated explants, α-SMA was significantly decreased in the CLECs cotreated with FGF/TGF-β. Smad-dependent and independent signalling was increased in the FGF-2/TGF-β2 co-treated CLECs, that had a heightened number of cells with nuclear localisation of Smad2/3 compared to the PLECs, that in contrast had more pronounced ERK1/2-signalling over Smad2/3 activation. The current study has confirmed that FGF-2 is influential in differentially regulating the behaviour of LECs during TGF-β-induced EMT, leading to a heterogenous cell population, typical of that observed in the development of post-surgical, posterior capsular opacification (PCO). This highlights the cooperative relationship between FGF and TGF-β leading to lens pathology, providing a different perspective when considering preventative measures for controlling PCO.

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Rogers, Andrea L. "Lens." Massachusetts Review 61, no. 4 (2020): 751–57. http://dx.doi.org/10.1353/mar.2020.0121.

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Semerci̇oğlu, Meli̇ke Güzi̇n. "Lens Tasarımcısının Optik Lens Geliştirme Süreçleri." International Journal of Innovative Approaches in Science Research 6, no. 2 (June 30, 2022): 116–32. http://dx.doi.org/10.29329/ijiasr.2022.454.8.

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Hendriks, B., and S. Kuiper. "Through a lens sharply [FluidFocus lens." IEEE Spectrum 41, no. 12 (December 2004): 32–36. http://dx.doi.org/10.1109/mspec.2004.1363638.

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Park, Sung Chan. "Zoom lens design using lens modules." Optical Engineering 35, no. 6 (June 1, 1996): 1668. http://dx.doi.org/10.1117/1.600742.

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Whittle, J. "Contact lens optics and lens design." Eye 21, no. 7 (July 2007): 1022. http://dx.doi.org/10.1038/sj.eye.6702607.

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Terazima, Masahide, and Noboru Hirota. "Population lens in thermal lens spectroscopy." Journal of Physical Chemistry 96, no. 18 (September 1992): 7147–50. http://dx.doi.org/10.1021/j100197a001.

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Taler, Kineret, Nour Zatari, Mohammad Iqbal Lone, Shahar Rotem-Bamberger, and Adi Inbal. "Identification of Small Molecules for Prevention of Lens Epithelium-Derived Cataract Using Zebrafish." Cells 12, no. 21 (October 29, 2023): 2540. http://dx.doi.org/10.3390/cells12212540.

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Cataract is the leading cause of blindness worldwide. It can be treated by surgery, whereby the damaged crystalline lens is replaced by a synthetic lens. Although cataract surgery is highly effective, a relatively common complication named posterior capsular opacification (PCO) leads to secondary loss of vision. PCO is caused by abnormal proliferation and migration of residual lens epithelial cells (LECs) that were not removed during the surgery, which results in interruption to the passage of light. Despite technical improvements to the surgery, this complication has not been eradicated. Efforts are being made to identify drugs that can be applied post-surgery, to inhibit PCO development. Towards the goal of identifying such drugs, we used zebrafish embryos homozygous for a mutation in plod3 that develop a lens phenotype with characteristics of PCO. Using both biased and unbiased approaches, we identified small molecules that can block the lens phenotype of the mutants. Our findings confirm the relevance of zebrafish plod3 mutants’ lens phenotype as a model for lens epithelium-derived cataract and add to our understanding of the molecular mechanisms that contribute to the development of this pathology. This understanding should help in the development of strategies for PCO prevention.

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Mahelková, Gabriela, L. Bačáková, J. Korynta, L. Vajner, and R. Vytásek. "Effect of Culture Substrate and Culture Conditions on Lens Epithelial Cell Proliferation and α-smooth Muscle Actin Expression." Folia Biologica 55, no. 2 (2009): 66–76. http://dx.doi.org/10.14712/fb2009055020066.

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The most common complication following cataract surgery is posterior capsule opacification. This results from migration, proliferation and transdifferentiation of residual lens epithelial cells (LECs). We studied the effect of several culture substrates and culture conditions on LEC proliferation and α-smooth muscle actin (α-SMA) expression. We used primary and secondary cultures of porcine LECs cultivated on collagen I, collagen IV, microscopic glass slides, and uncoated plastic dishes. We studied the cell proliferation and expression of α-SMA and α-, β-, and γ-crystallins. The effect of the medium exchange protocol was studied using the TOTL-86 rabbit epithelial lens cell line. There was no difference in growth characteristics of primary cultures on different substrates. In secondary cultures, LECs adhered better to collagen-coated surfaces. The culture substrate influenced LEC proliferation and α-SMA expression. The proliferation was greater when the medium was changed than when extra medium was added on the 4th day. The cells did not synthesize α-, βor γ-crystallin. The culture substrate influences the adhesion ability, proliferation and α-SMA expression in lens epithelial cells. In addition, it is necessary to consider the effects of the medium exchange protocol, serum supplementation, cell density and other cell culture conditions in lens epithelial cell experiments.

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Nugroho, Anggit, Ahmad Marzuki, and Trisno Subekti. "MANAJEMEN PERSEDIAAN DI OPTIK ROLISTA FIDA CIREBON." Jurnal Sehat Masada 14, no. 1 (January 6, 2020): 106–13. http://dx.doi.org/10.38037/jsm.v14i1.305.

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Persediaan merupakan asetpenting dari optik, hampir 90% dari total keseluruhan nilai investasi. Manajemen persediaan dilakukan agar dapa tmeminimalkan biaya persediaan. Kapan waktu dan berapa jumlah pemesanan harus diketahui dengan pasti agar tidak terjadi kekurangan atau kelebihan barang. Optik Rolista Fida sebagai usaha dagang dan pelayanan, masih melakukan pemesanan berdasarkan perkiraan atau ramalan (forecast) tidak berdasarkan perhitungan pasti kebutuhan barang yang akan dijual. Tujuan penelitian untuk mengetahui tingkat efesiensi pengadaan barang untuk persediaan, di Optik Rolista Fida Cirebon. Metode penelitian yang digunakan adalah study kasus dengan deskriptif kuantitatif, data yang terkumpul dari observasi dianalisis dengan menggunakan metode Ekonomic Order Quantity (EOQ). Hasil penelitian didapatkan gambaran pengadaan barang untuk Persediaan lebih efesien dengan menggunakan metode EOQ, berdasarkan perhitungan metode EOQ, jumlah pemesanan Frame : 265, Lensa : 687 dan Kontak Lens : 239. Frekuensi pemesanan Frame : 16, Lensa :13 danKontak Lens : 6 kali. Daur pemesanan Frame : 24, Lensa : 13 dan Kontak Lens : 63 hari.

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Chien, Ming-Chin, and Chung-Hao Tien. "Cluster LEDs mixing optimization by lens design techniques." Optics Express 19, S4 (June 9, 2011): A804. http://dx.doi.org/10.1364/oe.19.00a804.

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Gong, Yingying, Qingquan Wei, Liying Luo, Wei Qiu, and Yanyun Jiang. "A lipidomic study on the lens epithelial cells of patients with age related cataracts." PeerJ 12 (September 6, 2024): e17998. http://dx.doi.org/10.7717/peerj.17998.

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Age related cataracts (ARC) represent the main reason for blindness globally. The lens epithelial cells (LECs) participate not only in the metabolism of many substances in the lens but also in maintaining lens transparency. This study used lipidomics to investigate the metabolic differences in LECs of ARC patients with different severity, aiming at identifying potential metabolic biomarkers of ARC. Patients diagnosed with ARC and underwent cataract surgery at Shanghai Tongren Hospital were selected to participate in this study, which were classified as mild ARC group and severe ARC group. During their cataract surgery, anterior lens capsules(LCs) containing LECs were obtained. The lipidomics of LECs were analyzed using the liquid chromatography‑mass spectrometry (LC-MS). Potential pathways of lipids were searched for using databases such as the Kyoto Encyclopedia of Genes and Genomes (KEGG) and MetaboAnalyst platform. In LEC lipids, 26 lipids have been identified as potential biomarkers between mild ARC and severe ARC, with AUC values of 0.67–0.94. The pathway analysis results revealed that the Glycerophospholipid (GPL) metabolism was significantly influenced, indicating that these metabolic markers contribute significantly to regulating this pathway. The LEC metabolic spectrum demonstrates a proficient ability to differentiate between patients with varying levels of cataracts. Herein, we have successfully identified potential metabolic biomarkers and pathways that have proven to be valuable in enhancing our understanding of ARC pathogenesis. The finding has translational value for developing new cataract treatment methods in the future.

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Rizky Hidayat Prasetyo and Eko Tjipto Rahardjo. "Rotman Lens Size Reduction by Using Same-Size Double Rectangular Defected Ground Structures (DGSs) Method or Same-Size Double Rectangular Slots Method." Journal of Robotics, Automation, and Electronics Engineering 2, no. 1 (July 14, 2024): 30–38. http://dx.doi.org/10.21831/jraee.v2i1.555.

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The need for dedicated communication keeps increasing. A technique to realize that is by using multibeam radiation. A Beamforming Network (BFN) is required to enable multibeam capability in array antennas. This study uses the Rotman Lens as BFN in the frequency of S-Band. The common problem with using Rotman Lens is that its conventional design size is quite large, mainly due to its transition leg ports. Transition leg ports are important to ensure the matching impedance between the lens and the array antenna ports the lens and the beam ports or the lens and the dummy port. The goal of this study is to reduce the size of Rotman lens transition legs by implementing simple and uniform size of slots or Defected Ground Structures (DGSs) methods for the ports of the Rotman Lens BFN. The method can minimize the length of the transition leg and allow the BFN to operate efficiently. The results revealed that the use of the same double-rectangular DGS technique and the same double-rectangular slots in ports can reduce the size of the Rotman lens. Compared to the conventional methods, the proposed method can reduce the size to almost 85 percent from its original size for this S-Band implementation. The other performances of the BFN, besides the size reduction, are not degraded by implementing the proposed methods.

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Qin, Ying, Haoxin Liu, and Hongli Wu. "Cellular Senescence in Health, Disease, and Lens Aging." Pharmaceuticals 18, no. 2 (February 12, 2025): 244. https://doi.org/10.3390/ph18020244.

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Background: Cellular senescence is a state of irreversible cell cycle arrest that serves as a critical regulator of tissue homeostasis, aging, and disease. While transient senescence contributes to development, wound healing, and tumor suppression, chronic senescence drives inflammation, tissue dysfunction, and age-related pathologies, including cataracts. Lens epithelial cells (LECs), essential for maintaining lens transparency, are particularly vulnerable to oxidative stress-induced senescence, which accelerates lens aging and cataract formation. This review examines the dual role of senescence in LEC function and its implications for age-related cataractogenesis, alongside emerging senotherapeutic interventions. Methods: This review synthesizes findings on the molecular mechanisms of senescence, focusing on oxidative stress, mitochondrial dysfunction, and the senescence-associated secretory phenotype (SASP). It explores evidence linking LEC senescence to cataract formation, highlighting key studies on stress responses, DNA damage, and antioxidant defense. Recent advances in senotherapeutics, including senolytics and senomorphics, are analyzed for their potential to mitigate LEC senescence and delay cataract progression. Conclusions: LEC senescence is driven by oxidative damage, mitochondrial dysfunction, and impaired redox homeostasis. These factors activate senescence path-ways, including p53/p21 and p16/Rb, resulting in cell cycle arrest and SASP-mediated inflammation. The accumulation of senescent LECs reduces regenerative capacity, disrupts lens homeostasis, and contributes to cataractogenesis. Emerging senotherapeutics, such as dasatinib, quercetin, and metformin, show promise in reducing the senescent cell burden and modulating the SASP to preserve lens transparency.

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Wu, Tsung-Tien, Ying-Ying Chen, Chiu-Yi Ho, Tung-Chen Yeh, Gwo-Ching Sun, Ching-Jiunn Tseng, and Pei-Wen Cheng. "3H-1,2-Dithiole-3-Thione Protects Lens Epithelial Cells against Fructose-Induced Epithelial-Mesenchymal Transition via Activation of AMPK to Eliminate AKR1B1-Induced Oxidative Stress in Diabetes Mellitus." Antioxidants 10, no. 7 (July 6, 2021): 1086. http://dx.doi.org/10.3390/antiox10071086.

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Studies demonstrated that the receptor of advanced glycation end products (RAGE) induced epithelial-mesenchymal transition (EMT) formation in the lens epithelial cells (LECs) of diabetic cataracts. This work investigated how 3H-1,2-dithiole-3-thione (D3T) reduces EMT formation in LECs of the fructose-induced diabetes mellitus (DM). LECs were isolated during cataract surgery from patients without DM or with DM. In a rat model, fructose (10% fructose, eight weeks) with or without D3T (10 mg/kg/day) treatment induced DM, as verified by blood pressure and serum parameter measurements. We observed that the formation of advanced glycation end products (AGEs) was significantly higher in epithelial human lens of DM (+) compared to DM (−) cataracts. Aldose reductase (AKR1B1), AcSOD2, and 3-NT were significantly enhanced in the rat lens epithelial sections of fructose-induced DM, however, the phosphorylation level of AMPKT172 showed a reversed result. Interestingly, administration of D3T reverses the fructose-induced effects in LECs. These results indicated that AMPKT172 may be required for reduced superoxide generation and the pathogenesis of diabetic cataract. Administration of D3T reverses the fructose-induced EMT formation the LECs of fructose-induced DM. These novel findings suggest that the D3T may be a candidate for the pharmacological prevention of cataracts in patients with DM.

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Nurama, Linda, and Swono Sibagariang*. "Sistem Informasi Persediaan Dry Lens Untuk Lensa Kontak Berbasis WEB." JURNAL MAHAJANA INFORMASI 7, no. 1 (June 28, 2022): 42–49. http://dx.doi.org/10.51544/jurnalmi.v7i1.2953.

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Sistem yang baik mampu memberikan informasi dengan data yang akurat dan tepat dalam proses pengolahannya. Salah satu faktor yang terjadi di department Planning PT CIBA VISION BATAM adalah pencatatan informasi quantity per cavity untuk Dry Lens Air Optix Night and Day masih menggunakan file excel dimana semakin panjang file maka akan menyebabkan file yang akan dibuka lebih lambat. Data yang disimpan dalam file Microsoft Excel juga sangat tidak efektif karena jika terjadi kesalahan pada saat data diproses akan menyebabkan ketidaksesuaian informasi dan kehilangan data yang disebabkan oleh human error. Personnel Planning membutuhkan suatu sistem informasi yang dapat memberikan informasi ketersediaan Dry Lens Air Optix Night and Day per cavity. Perancangan sistem informasi persediaan Dry Lens per cavity ini berupa aplikasi sistem berbasis web yang dapat membantu dalam penyimpanan dan pengolahan data serta menampilkan hasil inventory Dry Lens per cavity sesuai dengan aktual dry lens yang tersedia di warehouse. Berdasarkan implementasi yang sudah dilakukan, sistem dapat menampilkan persediaan berdasarkan status yang ada sehingga tidak perlu melakukan sort data pada jumlah persediaan yang di export kedalam file excel.

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Lipnitskaya, S. N., I. I. Dudko, and I. G. Smirnova. "Numerical Simulation of Light Extraction from Remote Phosphor LED." Reviews on Advanced Materials and Technologies 4, no. 3 (2022): 35–41. http://dx.doi.org/10.17586/2687-0568-2022-4-3-35-41.

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In this paper, light extraction from remote phosphor LEDs were calculated in Zemax OpticStudio. The dependence of the optical characteristics of the remote phosphor LED on the parameters of phosphor and its geometrical form was considered. In case of a thin plate as a remote phosphor, phosphor particle size, phosphor mass fraction and phosphor plate thickness were carefully analyzed. Furthermore, a plane-convex lens and Fresnel lens were also considered as geometrical form of remote phosphor. The simulation results show that color coordinates of LED, using remote phosphor plate (thickness 0.25 mm, mass fraction 30% and particle size 3 μm of phosphor), are the closest to D65 point on color space compared to other considered LEDs. The use of plane-convex lens (thickness 1 mm, radius of curvature 7 mm, base diameter 7 mm) as remote phosphor results in the maximum luminous flux compared to other forms.

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ZHANG Jin-kai, 张金凯, 陈晓波 CHEN Xiao-bo, 邵海燕 SHAO Hai-yan, 王晓慧 WANG Xiao-hui, and 孙选 SUN Xuan. "Zoom lens design using mixed lens modules." Optics and Precision Engineering 26, no. 1 (2018): 38–47. http://dx.doi.org/10.3788/ope.20182601.0038.

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Vyas, Sameer, Satheesh Krishna, Ajay Kumar, and Niranjan Khandelwal. "′Floating lens sign′ in traumatic lens dislocations." Middle East African Journal of Ophthalmology 22, no. 1 (2015): 129. http://dx.doi.org/10.4103/0974-9233.148365.

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Zhong Liujun, 钟刘军, 安志勇 An Zhiyong, 高铎瑞 Gao Duorui, and 赵昭 Zhao Zhao. "All Lens Elements Movable Zoom Lens Design." Laser & Optoelectronics Progress 51, no. 12 (2014): 122202. http://dx.doi.org/10.3788/lop51.122202.

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Fine, I. Howard, Richard S. Hoffman, and Mark Packer. "Clear-Lens Extraction with Multifocal Lens Implantation." International Ophthalmology Clinics 41, no. 2 (2001): 113–21. http://dx.doi.org/10.1097/00004397-200104000-00011.

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Kuc, Christopher J., and Kenneth A. Lebow. "Contact Lens Solutions and Contact Lens Discomfort." Eye & Contact Lens: Science & Clinical Practice 44, no. 6 (November 2018): 355–66. http://dx.doi.org/10.1097/icl.0000000000000458.

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Journal articles on the topic 'Lens'

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