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1.
Surg Clin North Am ; 100(6): 971-992, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33128891

RESUMO

Surgeons have been involved, since the beginning, in the development and evolution of endoscopy. They have been instrumental in developing new methods and have been actively involved in most of the therapeutic applications. The continued evolution of endoscopic technique is inevitable and will involve the integration of new technology with innovative thinking.


Assuntos
Endoscópios Gastrointestinais/história , Endoscopia Gastrointestinal/história , Tecnologia de Fibra Óptica/história , Endoscopia Gastrointestinal/instrumentação , Endoscopia Gastrointestinal/tendências , Europa (Continente) , Tecnologia de Fibra Óptica/instrumentação , História do Século XIX , História do Século XX , História Antiga , Humanos , Óptica e Fotônica/história , Óptica e Fotônica/tendências , Estados Unidos
2.
Vestn Oftalmol ; 136(5. Vyp. 2): 237-240, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33063971

RESUMO

The authors present a clinical case of central opacification of the intraocular lens (IOL) optic associated with a significant uncorrectable visual acuity decrease. Due to high surgical risks of IOL exchange, corectopia was achieved through sectoral laser photomydriasis. Stable dilation of the lower nasal sector of the pupil enabled the optical zone to be shifted outside the opaque area of the IOL. As shown by the perimetry results, the visual field borders enlarged through sectoral laser photomydriasis were comparable with the topography of the asymmetrically dilated pupil.


Assuntos
Lentes Intraoculares , Falha de Prótese , Olho Artificial , Humanos , Óptica e Fotônica , Acuidade Visual
3.
Vestn Oftalmol ; 136(5. Vyp. 2): 296-300, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33063980

RESUMO

The review summarizes the results of surgical treatment of cataracts in patients with keratoconus. The major challenges of phacosurgery in keratoconus are associated with intraocular lens (IOL) power calculation, choice of the most appropriate IOL model and additional interventions required to stabilize keratectasia and reduce corneal irregularity.


Assuntos
Catarata , Ceratocone , Lentes Intraoculares , Catarata/complicações , Catarata/diagnóstico , Humanos , Ceratocone/diagnóstico , Ceratocone/cirurgia , Óptica e Fotônica , Refração Ocular
4.
Opt Lett ; 45(19): 5428-5431, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001920

RESUMO

We show that waveguide sensors can enable a quantitative characterization of coronavirus spike glycoprotein-host-receptor binding-the process whereby coronaviruses enter human cells, causing disease. We demonstrate that such sensors can help quantify and eventually understand kinetic and thermodynamic properties of viruses that control their affinity to targeted cells, which is known to significantly vary in the course of virus evolution, e.g., from SARS-CoV to SARS-CoV-2, making the development of virus-specific drugs and vaccine difficult. With the binding rate constants and thermodynamic parameters as suggested by the latest SARS-CoV-2 research, optical sensors of SARS-CoV-2 spike protein-receptor binding may be within sight.


Assuntos
Betacoronavirus , Técnicas Biossensoriais , Infecções por Coronavirus , Óptica e Fotônica/instrumentação , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Sítios de Ligação , Humanos , Ligação Proteica/fisiologia
5.
J Breath Res ; 14(4): 043001, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32969348

RESUMO

Cavity-enhanced absorption spectroscopies (CEAS) have gained importance in a wide range of applications in molecular spectroscopy. The development of optical sensors based on the CEAS techniques coupled with the continuous wave or pulsed laser sources operating in the mid-infrared or near-infrared spectral regime uniquely offers molecularly selective and ultra-sensitive detection of trace species in complex matrices including exhaled human breath. In this review, we discussed recent applications of CEAS for analyzing trace constituents within the exhaled breath matrix facilitating the non-invasive assessment of human health status. Next to a brief discussion on the mechanisms of formation of trace components found in the exhaled breath matrix related to particular disease states, existing challenges in CEAS and future development towards non-invasive clinical diagnostics will be discussed.


Assuntos
Testes Respiratórios/métodos , Expiração , Óptica e Fotônica/métodos , Animais , Humanos , Óxido Nítrico/análise , Consumo de Oxigênio , Espectroscopia de Luz Próxima ao Infravermelho
6.
Nature ; 585(7826): 506-507, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32968262
7.
Nat Commun ; 11(1): 4108, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796840

RESUMO

Replicating biological patterns is promising for designing materials with multifaceted properties. Twisted cholesteric liquid crystal patterns are found in the iridescent tessellated cuticles of many insects and a few fruits. Their accurate replication is extremely difficult since discontinuous patterns and colors must coexist in a single layer without discontinuity of the structures. Here, a solution is demonstrated by addressing striped insect cuticles with a complex twisted organization. Geometric constraints are met by controlling the thermal diffusion in a cholesteric oligomer bilayer subjected to local changes in the molecular anchoring conditions. A multicriterion comparison reveals a very high level of biomimicry. Proof-of-concept prototypes of anti-counterfeiting tags are presented. The present design involves an economy of resources and a high versatility of chiral patterns unreached by the current manufacturing techniques such as metallic layer vacuum deposition, template embossing and various forms of lithography which are limited and often prohibitively expensive.


Assuntos
Biomimética/métodos , Biofísica/métodos , Cristais Líquidos/química , Óptica e Fotônica/métodos , Animais , Insetos
9.
Proc Natl Acad Sci U S A ; 117(29): 17260-17268, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32632007

RESUMO

Understanding how a network of interconnected neurons receives, stores, and processes information in the human brain is one of the outstanding scientific challenges of our time. The ability to reliably detect neuroelectric activities is essential to addressing this challenge. Optical recording using voltage-sensitive fluorescent probes has provided unprecedented flexibility for choosing regions of interest in recording neuronal activities. However, when recording at a high frame rate such as 500 to 1,000 Hz, fluorescence-based voltage sensors often suffer from photobleaching and phototoxicity, which limit the recording duration. Here, we report an approach called electrochromic optical recording (ECORE) that achieves label-free optical recording of spontaneous neuroelectrical activities. ECORE utilizes the electrochromism of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) thin films, whose optical absorption can be modulated by an applied voltage. Being based on optical reflection instead of fluorescence, ECORE offers the flexibility of an optical probe without suffering from photobleaching or phototoxicity. Using ECORE, we optically recorded spontaneous action potentials in cardiomyocytes, cultured hippocampal and dorsal root ganglion neurons, and brain slices. With minimal perturbation to cells, ECORE allows long-term optical recording over multiple days.


Assuntos
Eletrofisiologia/métodos , Neurônios/fisiologia , Poliestirenos , Tiofenos , Potenciais de Ação/fisiologia , Encéfalo/citologia , Encéfalo/fisiologia , Técnicas Eletroquímicas/métodos , Fenômenos Eletrofisiológicos , Corantes Fluorescentes , Gânglios Espinais/citologia , Gânglios Espinais/fisiologia , Humanos , Imagem Óptica , Óptica e Fotônica/métodos
10.
Curr Opin Ophthalmol ; 31(4): 284-287, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32487810

RESUMO

PURPOSE OF REVIEW: Intraocular lens (IOL) calculations in patients with keratoconus and other keratoectatic disorders continues to be a challenge for today's cataract surgeon. In this article, we review data published over the past 18 months (June 2018 to January 2020). RECENT FINDINGS: Cataract surgery in keratoconus patients has the potential to greatly improve patients' vision. However, keratoconic eyes are notorious for unpredictable outcomes because of difficulty in obtaining proper preoperative biometry and lack of data and consensus on IOL calculation formulas that can reliable in providing the desired outcome. Recent studies suggest the Barrett II Universal calculation is the most accurate in mild-to-moderate keratoconic eyes. All studies note the level of predictability decreases with the steepness of keratometric readings. Historically, the SRK/T has been shown to provide the most reliable calculations. SUMMARY: There is still no consensus on which formula is best for IOL calculation in keratoconic eyes. On the basis of the most recent literature, we recommend using the Barrett II Universal in conjunction with the SRK/T formula for mild-to-moderate eyes. Preoperative counseling of expectations with the patient is the key to achieving a satisfied patient and avoiding an unpleasant situation in the result of refractive surprise.


Assuntos
Biometria/métodos , Extração de Catarata , Ceratocone/complicações , Lentes Intraoculares , Óptica e Fotônica , Humanos , Ceratocone/fisiopatologia , Acuidade Visual/fisiologia
11.
Curr Opin Ophthalmol ; 31(4): 253-260, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32487811

RESUMO

PURPOSE OF REVIEW: The subject of artificial intelligence has recently been responsible for the advancement of many industries including aspects of medicine and many of its subspecialties. Within ophthalmology, artificial intelligence technology has found ways of improving the diagnostic and therapeutic processes in cornea, glaucoma, retina, and cataract surgery. As demands on the modern ophthalmologist grow, artificial intelligence can be utilized to help address increased demands of modern medicine and ophthalmology by adding to the physician's clinical and surgical acumen. The purpose of this review is to highlight the integration of artificial intelligence into ophthalmology in recent years in the areas of cornea, refractive, and cataract surgery. RECENT FINDINGS: Within the realms of cornea, refractive, and cataract surgery, artificial intelligence has played a major role in identifying ways of improving diagnostic detection. In keratoconus, artificial intelligence algorithms may help with the early detection of keratoconus and other ectatic disorders. In cataract surgery, artificial intelligence may help improve the performance of intraocular lens (IOL) calculation formulas. Further, with its potential integration into automated refraction devices, artificial intelligence can help provide an improved framework for IOL formula optimization that is more accurate and customized to a specific cataract surgeon. SUMMARY: The future of artificial intelligence in ophthalmology is a promising prospect. With continued advancement of mathematical and computational algorithms, corneal disease processes can be diagnosed sooner and IOL calculations can be made more accurate.


Assuntos
Inteligência Artificial , Extração de Catarata , Doenças da Córnea/diagnóstico , Procedimentos Cirúrgicos Refrativos , Biometria/métodos , Humanos , Lentes Intraoculares , Óptica e Fotônica
12.
Nature ; 582(7810): 37-38, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32494075
13.
Vestn Oftalmol ; 136(3): 100-105, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32504484

RESUMO

Approximately 470 thousand cases of cataract surgery with implantation of intraocular lens (IOL) are performed annually in Russia. The distribution of IOL power in the Russian population has not been studied sufficiently, which makes the IOL procurement planning imperfect. PURPOSE: To analyze the distribution of implanted IOL power and optimize the IOL procurement system. MATERIAL AND METHODS: Retrospective analysis of cataract surgeries performed from 2014 to 2015 in the ophthalmic department of Volga District Medical Centre of the FMBA was conducted. Inclusion criteria: age from 20 to 99 years, no refractive surgery in patient's medical history, primary IOL implantation with an A-constant of 118.4, achievement of planned refraction. The studied parameters were IOL power, gender and age of patients. To assess the effectiveness of the procurement system, we analyzed the number of additional «unplanned¼ purchases and exchanges of IOLs over the course of 5 years (2014-2018). RESULTS: According to the inclusion criteria, 1009 medical records were selected, the age of the patients was 68.7±10.9 years. The distribution of IOL power was similar, but different from the normal, characterized by the mismatch of the median and the mean, left-sided asymmetry and peaked shape. Comparison of 2014 and 2015 samples showed no significant differences and low variability of IOL power. Regression analysis revealed a weak correlation between the IOL power and age and no correlation with gender, a trend was observed for IOL power to increase in patients after 50 years. The use of a procurement planning system based on a mathematical model of the IOL power distribution allows reduction of the additional purchases and exchanges of IOLs with the supplier from 5-7% to 1-2% of the total purchases. CONCLUSION: The specific features of the IOL power distribution are related to the distribution of biometry parameters in the population. The use of a scientifically based procurement system reduces staff time and laboring costs, releasing economical and time resources.


Assuntos
Implante de Lente Intraocular , Lentes Intraoculares , Adulto , Idoso , Idoso de 80 Anos ou mais , Biometria , Humanos , Pessoa de Meia-Idade , Óptica e Fotônica , Refração Ocular , Estudos Retrospectivos , Federação Russa , Adulto Jovem
15.
Nat Commun ; 11(1): 2708, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488070

RESUMO

Although many animals have evolved intrinsic transparency for the purpose of concealment, the development of dynamic, that is, controllable and reversible, transparency for living human cells and tissues has remained elusive to date. Here, by drawing inspiration from the structures and functionalities of adaptive cephalopod skin cells, we design and engineer human cells that contain reconfigurable protein-based photonic architectures and, as a result, possess tunable transparency-changing and light-scattering capabilities. Our findings may lead to the development of unique biophotonic tools for applications in materials science and bioengineering and may also facilitate an improved understanding of a wide range of biological systems.


Assuntos
Engenharia Celular/métodos , Cefalópodes , Óptica e Fotônica , Animais , Técnicas de Cultura de Células , Feminino , Engenharia Genética , Células HEK293 , Humanos , Proteínas/química , Pele , Biologia Sintética/métodos
16.
Vestn Oftalmol ; 136(2): 38-43, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32366068

RESUMO

PURPOSE: To test a prediction algorithm for deflection of the optical part of IOL after uncomplicated phacoemulsification. MATERIAL AND METHODS: The study included 226 patients (287 eyes) who underwent phacoemulsification with implantation of intracapsular AcrySof IOL. Preoperative examination included IOLMaster, Lenstar LS 900 biometry and Pentacam HR keratotopography. All measurement were repeated one month postoperatively. To determine the tilt and deflection of the IOL's optical part, anterior segment optical coherence tomography (OCT) was performed on Topcon 3DOCT-2000. RESULTS: OCT data analysis helps identify the slope and deflection of the IOL's optical part relative to the pupil plane. In the previous study we built logistic regression models for predicting the deflection of the IOL's optical part with high predictive quality based on the calculated IOL power and preoperative biometry measurements. When checked with new patient data, the areas under the ROC curves have changed slightly. Large area under the ROC curves with small deviation rates, as well as retention of the level of true positive responses with little increase in false negative responses verify the high quality of the models. CONCLUSION: Logistic regression models based on the optical power of the implanted IOL, as well as on a combination of preoperative biometry data from IOLMaster and Lenstar LS 900, make it possible to predict the probability of deflection of the optical part of IOL with high reliability and promptly correct the IOL power.


Assuntos
Lentes Intraoculares , Facoemulsificação , Algoritmos , Biometria , Humanos , Óptica e Fotônica , Reprodutibilidade dos Testes , Tomografia de Coerência Óptica
17.
Am J Ophthalmol ; 217: 81-90, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32387430

RESUMO

PURPOSE: To compare the prediction accuracy of new intraocular lens (IOL) calculation formulas (Barrett Universal II [BUII], Emmetropia Verifying Optical [EVO], Kane and Ladas Super formula) and traditional formulas (Haigis, Hoffer Q, Holladay 1, and SRK/T) with Wang-Koch (WK) axial length (AL) adjustment in vitrectomized eyes. DESIGN: Retrospective consecutive case-series study. METHODS: One hundred eleven eyes of 111 patients underwent uneventful phacoemulsification and enVista MX60 implantation after vitrectomy were enrolled and divided into 4 groups according to whether the vitreous cavity was filled with silicone oil. The performance of each formula was evaluated with or without lens constant optimization. RESULTS: Before lens constants optimization, the mean prediction errors (MEs) of all formulas were statistically different from zero (0.14-0.46 diopters [D]) in vitrectomized eyes, except for the Kane formula. The BUII, EVO, Kane, and Haigis had relatively lower mean absolute error (MAE) and median absolute error (MedAE) with optimized constants. No significant systemic bias was found in new formulas for vitrectomized eyes with AL >26 mm (P > .05). The Hoffer Q and Holladay 1 displayed significantly hyperopic shift (0.39 and 0.51 D) for long eyes, which was corrected by the WK adjustment. There were no significant differences in the prediction accuracy of all formulas among 4 subgroups (P > .05). CONCLUSIONS: The BUII, EVO, Kane, and Haigis displayed comparable performance in vitrectomized eyes with optimized constants. In vitrectomized highly myopic eyes, the new formulas and traditional formulas with WK adjustment exhibited satisfactory prediction accuracy. Silicone oil tamponade did not affect the prediction accuracy of formulas using IOLMaster 700.


Assuntos
Lentes Intraoculares , Óptica e Fotônica , Erros de Refração/fisiopatologia , Acuidade Visual , Vitrectomia , Biometria , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Facoemulsificação , Período Pós-Operatório , Desenho de Prótese , Refração Ocular , Reprodutibilidade dos Testes , Estudos Retrospectivos
18.
J Vis Exp ; (159)2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32449728

RESUMO

Demonstrated is a unique method for sensing performance enhancement in Brillouin optical time-domain analyzers (BOTDA). A Brillouin gain spectrum (BGS) is superimposed with two symmetric Brillouin loss spectra (BLS). This leads to a complex engineered spectrum shape that is more resistant to the sensing system noise. Instead of only one pump and probe interaction as in the conventional BOTDA setup, three optical probe waves are exploited, with one probe located in the BGS and the other two symmetrically in the BLS. Due to the resistance and insensitivity of the engineered spectrum shape to the noise, the sensing performance is enhanced by 60% and the measurand resolution is doubled.


Assuntos
Algoritmos , Óptica e Fotônica , Simulação por Computador , Fatores de Tempo
19.
Nature ; 580(7802): 188-189, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32269348
20.
Opt Express ; 28(3): 2661-2682, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32121950

RESUMO

A methodology is developed for deriving consistent ocean biological and biogeochemical products from multiple satellite ocean color sensors that have slightly different sensor spectral characteristics. Specifically, the required coefficients for algorithm modifications are obtained using the hyperspectral in situ optical measurements from the Marine Optical Buoy (MOBY) in the water off Hawaii. It is demonstrated that using the proposed approach for modifying ocean biological and biogeochemical algorithms, satellite-derived ocean property data over the global open ocean are consistent from multiple satellite sensors, although their corresponding sensor-measured normalized water-leaving radiance spectra nLw(λ) are different. Therefore, the proposed approach allows satellite-derived ocean biological and biogeochemical products to be consistent and can therefore be routinely merged from various satellite ocean color sensors. The proposed approach can be applied to any satellite algorithms that use the input of sensor-measured nLw(λ) spectra.


Assuntos
Monitoramento Ambiental/instrumentação , Oceanos e Mares , Comunicações Via Satélite , Algoritmos , Clorofila A/análise , Cor , Óptica e Fotônica
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