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1.
Comput Methods Programs Biomed ; 178: 265-273, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31416554

RESUMO

BACKGROUND AND OBJECTIVES: The statistical shape model (SSM) of numerous bones has been used to determine the anatomical representative of the population- or race-specific design for periarticular implants. Whether to include size- and profile-mismatched bones in the SSM calculation is debatable. Therefore, the objective of this study was to characterize the screening strategies for the mismatched bones to improve the SSM calculation. METHODS: The bone database used in this study consisted of 20 pelvises. A systematic four-staged SSM calculation was used to evaluate the accuracy of the predicted SSM shape among the four size- and profile-screening strategies. Additionally, the surface-smoothing effects on the SSM results were investigated. Two comparison indices were used in terms of profile difference and surface smoothness. RESULTS: Significant variations in size and profile existed for the collected bones. By normalizing the aspect ratio of all bones, exclusion of the size-mismatched bones reduced the maximum and root mean square (RMS) error values of the profile difference by 18.9% and 17.5%, respectively. After further excluding the profile-improper bones, normalization reduced the RMS profile difference by 24.1% compared with the non-normalized strategy. Exclusion of the size-improper bones for non-normalized strategy would have reduced the RMS profile difference by 15.4%. After smoothness, the RMS profile difference of SSM was only 6.1% higher than that of the non-smoothness SSM. CONCLUSIONS: The four-stage calculation showed that the most favorable strategy was to normalize bones to the same aspect ratio and exclude improperly shaped bones. The model permitted inclusion of the original characteristics of the bones and preserved their shapes and excluded only significantly improper bones. After SSM calculation, the smoothed process provided satisfaction in quality with a statistically insignificant loss in bone morphology for population- or race-specific designs of implants.

2.
Biomacromolecules ; 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31356057

RESUMO

Thermoresponsive hydrogels are used for an array of biomedical applications. Lower critical solution temperature-type hydrogels have been observed in nature and extensively studied in comparison to upper critical solution temperature (UCST)-type hydrogels. Of the limited protein-based UCST-type hydrogels reported, none have been composed of a single coiled-coil domain. Here, we describe a biosynthesized homopentameric coiled-coil protein capable of demonstrating a UCST. Microscopy and structural analysis reveal that the hydrogel is stabilized by molecular entanglement of protein nanofibers, creating a porous matrix capable of binding the small hydrophobic molecule, curcumin. Curcumin binding increases the α-helical structure, fiber entanglement, mechanical integrity, and thermostability, resulting in sustained drug release at physiological temperature. This work provides the first example of a thermoresponsive hydrogel comprised of a single coiled-coil protein domain that can be used as a vehicle for sustained release and, by demonstrating UCST-type behavior, shows promise in forging a relationship between coiled-coil protein-phase behavior and that of synthetic polymer systems.

3.
Dermatol Surg ; 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30939521

RESUMO

BACKGROUND: Nail braces are an alternative treatment for ingrown toenails. OBJECTIVE: This study aimed to prospectively examine the efficacy of nail braces for treatment of acute inflamed (AI)-type and chronic dystrophic-type ingrown toenails. MATERIALS AND METHODS: The authors conducted a prospective study of patients with ingrown toenails treated at Wan Fang Hospital between January 1, 2017, and July 31, 2018. Evaluation using physician global assessment scores and patient satisfaction questionnaires was performed at 1, 3, and 6 months after the start of treatment and during the final visit. Patient demographics, treatment courses, and outcomes were compared between the 2 types of ingrown toenails. RESULTS: Chronic dystrophic-type and AI-type ingrown toenails were observed in 25 (61 sides) and 28 patients (35 sides), respectively. Of the affected sides, 80.9%, 94.9%, and 100% achieved an excellent or fair result at 1, 3, and 6 months, respectively. Treatment duration and follow-up period were 179.2 ± 96.8 days and 281.6 ± 120.9, respectively. The recurrence rate was 7.4%. The treatment course and response were different between the 2 types of ingrown toenails. CONCLUSION: Ingrown toenails could be effectively treated with nail braces with excellent outcomes, favorable patient satisfaction, and low recurrence rates.

5.
Nat Commun ; 10(1): 1082, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842417

RESUMO

Conventional microwave imagers usually require either time-consuming data acquisition, or complicated reconstruction algorithms for data post-processing, making them largely ineffective for complex in-situ sensing and monitoring. Here, we experimentally report a real-time digital-metasurface imager that can be trained in-situ to generate the radiation patterns required by machine-learning optimized measurement modes. This imager is electronically reprogrammed in real time to access the optimized solution for an entire data set, realizing storage and transfer of full-resolution raw data in dynamically varying scenes. High-accuracy image coding and recognition are demonstrated in situ for various image sets, including hand-written digits and through-wall body gestures, using a single physical hardware imager, reprogrammed in real time. Our electronically controlled metasurface imager opens new venues for intelligent surveillance, fast data acquisition and processing, imaging at various frequencies, and beyond.

6.
Int J Infect Dis ; 80: 16-27, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30529371

RESUMO

BACKGROUND AND AIM: Chronic hepatitis C is a major global health challenge. China has the world's largest burden of hepatitis C and related liver disease, with several groups having an increased risk of acquiring hepatitis C virus (HCV) infection. We undertook a systematic review in Chinese and English literature to determine the seroprevalence of anti-HCV among men who have sex with men (MSM), sex workers, people who use drugs (PWUD) and migrant workers in China. METHODS: We searched three Chinese databases (CNKI, Wanfang and Chongqing VIP Information) and four English databases (Pubmed, EMBASE, Global Health and CINAHL) for studies published between 2010 and 2015. Included were 89 studies for MSM, 112 for sex workers, 11 for migrant workers, 94 for people who inject drugs (PWID) and 67 for non-injectors. Random-effect models pooled estimates of anti-HCV seroprevalence in each population and a meta-regression model examined the relationship between anti-HCV seroprevalence and injecting drug use. RESULTS: The overall pooled seroprevalence of anti-HCV among MSM was 0.67% (CI 95 0.51-0.86); for sex workers 0.65% (CI 95 0.53-0.77); for migrant workers 0.48 (CI 95 0.20-0.85); for IDUs 72.41% (CI 95 68.71-75.97); among non-injectors 25.07% (CI 95 21.51%-28.80%). Our meta-regression model predicted that the seroprevalence of anti-HCV among PWID increased by 8.6% for each 10% increase seroprevalence of reporting ever having injected drugs. CONCLUSIONS: Overall, seroprevalence of HCV infection is high among PWUD, especially those who inject. Lower HCV seroprevalence (<1%) was found among MSM, sex workers and migrant workers. Our estimates for IDU seroprevalence are higher than that from the national surveillance system, though estimates for other at-risk populations are similar.


Assuntos
Hepatite C/epidemiologia , China/epidemiologia , Bases de Dados Factuais , Usuários de Drogas , Hepacivirus/isolamento & purificação , Homossexualidade Masculina , Humanos , Masculino , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Profissionais do Sexo , Migrantes
7.
Soft Robot ; 2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30407120

RESUMO

The ability to regulate the mechanical stiffness in a large range could be extremely important for soft robots to interact with the environment more effectively. In this article, we propose a novel chain-like granular jamming mechanism to achieve a large range of stiffness variation instantly, based on a method that is totally different from existing vacuum-based granular jamming systems. Theoretical modeling is introduced to find the best combination of granules to form the chain-like structure (CLS) and experiments are conducted to demonstrate it. The experimental results indicate that the novel jamming structure is able to achieve a stiffness variation range as large as 50.7 folds. To further validate the effectiveness of the CLS, a soft-rigid hybrid actuator based on the jamming structure is proposed and an integrated fabrication method is provided. Furthermore, an anthropomorphic hand based on the hybrid actuators is developed and the experimental results show that the hand is not only versatile enough to manipulate various objects with different weights, material properties, shapes, and surface characteristics at the soft state, like existing soft grippers, but also can lift heavy objects (1.5 kg in a cylindrical grasping gesture and 3.52 kg in a hook gesture) at the rigid state, which could be difficult for other soft grippers. Finally, the hand is integrated into our homemade service robot, significantly improving the practicability and safety of the robot when serving humans.

8.
Sci Adv ; 4(9): eaat7459, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30255146

RESUMO

Coxsackievirus A10 (CVA10) recently emerged as a major pathogen of hand, foot, and mouth disease and herpangina in children worldwide, and lack of a vaccine or a cure against CVA10 infections has made therapeutic antibody identification a public health priority. By targeting a local isolate, CVA10-FJ-01, we obtained a potent antibody, 2G8, against all three capsid forms of CVA10. We show that 2G8 exhibited both 100% preventive and 100% therapeutic efficacy against CVA10 infection in mice. Comparisons of the near-atomic cryo-electron microscopy structures of the three forms of CVA10 capsid and their complexes with 2G8 Fab reveal that a single Fab binds a border region across the three capsid proteins (VP1 to VP3) and explain 2G8's remarkable cross-reactivities against all three capsid forms. The atomic structures of this first neutralizing antibody of CVA10 should inform strategies for designing vaccines and therapeutics against CVA10 infections.

9.
J Dtsch Dermatol Ges ; 16(7): 845-851, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29972626

RESUMO

Many studies have reported the prevalence of autoantibodies in patients with vitiligo; however, results were inconsistent for some autoantibodies. This study aimed to conduct a systematic review and meta-analysis of the prevalence of autoantibodies in vitiligo patients. A systematic review and meta-analysis of the literature published from inception to Dec 31, 2016 was conducted. Case-control studies with vitiligo patients and a control group were included. The prevalence of anti-thyroperoxidase (ATPO) antibodies, anti-thyroglobulin (ATG) antibodies, antinuclear antibodies (ANA), anti-gastric parietal cell antibodies (AGPCA), anti-smooth muscle antibodies (ASMA), anti-mitochondrial antibodies (AMA), and anti-adrenal antibodies in vitiligo patients were 15.1 %, 9.7 %, 12.5 %, 11.7 %, 12.6 %, 0.2 %, and 2.5 %, respectively. The prevalence of ATPO antibodies (odds ratio [OR]: 3.975; 95 %; confidence interval [CI]: 3.085-5.122), ATG antibodies (OR: 3.759; 95 % CI: 2.554-5.531), ANA (OR: 1.797, 95 % CI: 1.182-2.731), AGPCA (OR: 2.503; 95 % CI: 1.497-2.896), and anti-adrenal antibodies (OR: 9.808, 95 % CI: 1.809-53.159) (Figure 2a-e) were significantly higher in vitiligo patients than in the control group. The routine screening of anti-thyroid antibodies should be performed in vitiligo patients to identify those at high risk of developing autoimmune thyroid disease.

10.
11.
J Healthc Eng ; 2018: 2723178, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30002803

RESUMO

Fast walking is a common exercise for most people to promote health. However, a higher cadence due to fast walking on ordinary or uneven ground raises the risk of tripping. To investigate the tripping issue, research to observe the gait in fast walking is needed. To explore the relationship between fast gait and the risk of tripping, a gait recording system with a specific synchronization mechanism was developed in this work. The system can acquire gait signals from wearable sensors and action cameras at different cadences. Meanwhile, algorithms for gait cycle segmentation and characteristic extraction were proposed for analyzing a fast gait. In the gait analysis, the correlations of low, moderate, and high cadence in cueing and no cueing gaits were computed, and two results were obtained. First, the higher the cadence is, the larger the motion strength in the terminal foot swing will be and the smaller the motion strength at the starting foot swing. Second, the decreased distance of foot clearance becomes more conspicuous as the cadence increased, especially if one is walking more than 120 beats. The results indicate that fast walking with bigger strides and lower cadence is the best way to maintain safety in moving over ordinary ground.

12.
Dev Cell ; 45(4): 481-495.e8, 2018 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-29754800

RESUMO

Cell and organelle membranes consist of a complex mixture of phospholipids (PLs) that determine their size, shape, and function. Phosphatidylcholine (PC) is the most abundant phospholipid in eukaryotic membranes, yet how cells sense and regulate its levels in vivo remains unclear. Here we show that PCYT1A, the rate-limiting enzyme of PC synthesis, is intranuclear and re-locates to the nuclear membrane in response to the need for membrane PL synthesis in yeast, fly, and mammalian cells. By aligning imaging with lipidomic analysis and data-driven modeling, we demonstrate that yeast PCYT1A membrane association correlates with membrane stored curvature elastic stress estimates. Furthermore, this process occurs inside the nucleus, although nuclear localization signal mutants can compensate for the loss of endogenous PCYT1A in yeast and in fly photoreceptors. These data suggest an ancient mechanism by which nucleoplasmic PCYT1A senses surface PL packing defects on the inner nuclear membrane to control PC homeostasis.


Assuntos
Membrana Celular/química , Núcleo Celular/química , Colina-Fosfato Citidililtransferase/metabolismo , Elasticidade , Membrana Nuclear/química , Fosfatidilcolinas/metabolismo , Estresse Fisiológico , Animais , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Colina-Fosfato Citidililtransferase/genética , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Homeostase , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Membrana Nuclear/genética , Membrana Nuclear/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo
13.
J Dtsch Dermatol Ges ; 16(4): 417-425, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29645396

RESUMO

HINTERGRUND UND ZIELE: Die Behandlung kompliziert eingewachsener Zehennägel ist eine Domäne der Chirurgie. Allerdings liegen Berichte vor, nach denen alternative Therapieformen mit Nagelspangen eine gute Wirksamkeit zeigen. Ziel der vorliegenden Studie war es, die Wirksamkeit einer neuen Nagelspange zur Behandlung eingewachsener Zehennägel zu untersuchen. PATIENTEN UND METHODEN: Wir führten eine retrospektive Studie an Patienten mit eingewachsenen Zehennägeln durch, die zwischen dem 1. Juni 2015 und dem 30. Mai 2016 im Krankenhaus Wan Fang behandelt wurden. Eingewachsene Zehennägel wurden in akut entzündete/infizierte (AI) und chronisch dystrophische (CD) Typen eingeteilt. Unter Verwendung des Physician Global Assessment (PGA) wurde die Wirksamkeit von Nagelspangen für die beiden Typen von eingewachsenen Zehennägeln 1, 2, 3 und 6 Monate nach Beginn der Behandlung und während des letzten Arztbesuchs verglichen. ERGEBNISSE: 21 Patienten (42 Stellen) hatten eingewachsene Zehennägel des CD-Typs; 25 Patienten (36 Stellen) hatten eingewachsene Zehennägel des AI-Typs. Von den betroffenen Stellen zeigten nach 1, 3 bzw. 6 Monaten 81 %, 94 % bzw. 100 % ein ausgezeichnetes oder akzeptables Ergebnis. Die Rezidivrate betrug 10,3 %, die Komplikationsrate 7,7 %. Während eingewachsene Zehennägel des AI-Typs in den ersten drei Monaten schneller hervorragende Ergebnisse erzielten als CD-Typ-Nägel, glichen sich die Ergebnisse nach sechs Monaten an. SCHLUSSFOLGERUNGEN: Nagelspangen sind eine wirksame therapeutische Option, insbesondere für eingewachsene Zehennägel vom CD-Typ.

14.
J Cell Sci ; 131(8)2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29567856

RESUMO

Phototransduction in Drosophila is mediated by phospholipase C-dependent hydrolysis of PIP2-, and is an important model for phosphoinositide signalling. Although generally assumed to operate by generic machinery conserved from yeast to mammals, some key elements of the phosphoinositide cycle have yet to be identified in Drosophila photoreceptors. Here, we used transgenic flies expressing fluorescently tagged probes (P4M and TbR332H), which allow in vivo quantitative measurements of PI4P and PIP2 dynamics in photoreceptors of intact living flies. Using mutants and RNA interference for candidate genes potentially involved in phosphoinositide turnover, we identified Drosophila PI4KIIIα (CG10260) as the PI4-kinase responsible for PI4P synthesis in the photoreceptor membrane. Our results also indicate that PI4KIIIα activity requires rbo (the Drosophila orthologue of Efr3) and CG8325 (orthologue of YPP1), both of which are implicated as scaffolding proteins necessary for PI4KIIIα activity in yeast and mammals. However, our evidence indicates that the recently reported central role of dPIP5K59B (CG3682) in PIP2 synthesis in the rhabdomeres should be re-evaluated; although PIP2 resynthesis was suppressed by RNAi directed against dPIP5K59B, little or no defect was detected in a reportedly null mutant (dPIP5K18 ).

15.
J Dtsch Dermatol Ges ; 16(4): 417-423, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29500908

RESUMO

BACKGROUND AND OBJECTIVES: Surgery is the mainstay of treatment for complicated ingrown toenails. However, alternative treatments using nail braces have been reported to show good efficacy. The objective of the present study was to investigate the efficacy of a new nail brace for the treatment of ingrown toenails. PATIENTS AND METHODS: We conducted a retrospective study on patients with ingrown toenails treated at Wan Fang Hospital between June 1, 2015 and May 30, 2016. Ingrown toenails were classified into acute inflamed/infected (AI) and chronic dystrophic (CD) types. Using physician global assessment scores, the efficacy of nail braces for the two types of ingrown toenails was compared 1, 2, 3, and 6 months after treatment initiation and during the final visit. RESULTS: Twenty-one patients (42 sites) had CD-type ingrown toenails; 25 patients (36 sites) had ingrown toenails of the AI type. Of the affected sites, 81 %, 94 %, and 100 % showed an excellent or fair outcome at 1, 3, and 6 months, respectively. Recurrence rates were 10.3 %; complication rates, 7.7 %. While, in the first three months, AI-type ingrown toenails tended to achieve excellent results more rapidly than CD-type nails, outcomes were similar at six months. CONCLUSIONS: Nail braces are an effective therapeutic option, particularly for CD-type ingrown toenails.

16.
Viruses ; 10(1)2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29361773

RESUMO

Zika virus (ZIKV) has been defined as a teratogenic pathogen behind the increased number of cases of microcephaly in French Polynesia, Brazil, Puerto Rico, and other South American countries. Experimental studies using animal models have achieved tremendous insight into understanding the viral pathogenesis, transmission, teratogenic mechanisms, and virus-host interactions. However, the animals used in published investigations are mostly interferon (IFN)-compromised, either genetically or via antibody treatment. Herein, we studied ZIKV infection in IFN-competent mice using African (MR766) and Asian strains (PRVABC59 and SZ-WIV01). After testing four different species of mice, we found that BALB/c neonatal mice were resistant to ZIKV infection, that Kunming, ICR and C57BL/6 neonatal mice were fatally susceptible to ZIKV infection, and that the fatality of C57BL/6 neonates from 1 to 3 days old were in a viral dose-dependent manner. The size and weight of the brain were significantly reduced, and the ZIKV-infected mice showed neuronal symptoms such as hind-limb paralysis, tremor, and poor balance during walking. Pathologic and immunofluorescent experiments revealed that ZIKV infected different areas of the central nervous system (CNS) including gray matter, hippocampus, cerebral cortex, and spinal cord, but not olfactory bulb. Interestingly, ZIKV replicated in multiple organs and resulted in pathogenesis in liver and testis, implying that ZIKV infection may engender a high health risk in neonates by postnatal infection. In summary, we investigated ZIKV pathogenesis using an animal model that is not IFN-compromised.

17.
J Chin Med Assoc ; 81(5): 475-481, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29133160

RESUMO

BACKGROUND: In endurance sports, stress, dehydration and release of chemical factors have been associated with red blood cell (RBC) alterations of structure and function, which may contribute to sports anemia, a well-observed phenomenon during long-distance running. Until now, the investigation of the changes of viscoelastic properties of RBC membrane, a decisive factor of RBC deformability to avoid hemolysis, is lacking, especially in an Oriental population. METHODS: nineteen runners were prospectively recruited into our study. Hematological parameters were analyzed before and immediately after the 2015 Taipei 24H Ultra-Marathon Festival, Taiwan. Video particle tracking microrheology was used to determine viscoelastic properties of each RBC sample by calculating the dynamic elastic modulus G'(f) and the viscous modulus G″(f) at frequency f = 20 Hz. RESULTS: Haptoglobin, RBC count, hemoglobin, hematocrit, mean cell hemoglobin, plasma free hemoglobin and unsaturated iron-binding capacity values of the recruited runners showed a statistically significant drop in the post-race values. Blood concentration of reticulocyte and ferritin were significantly higher at post-race compared with pre-race. 15 out of the 19 runners had a concurrent change in the elastic and the viscous moduli of their RBCs. Changes in the elastic and the viscous moduli were correlated with changes in the RBC count, hemoglobin and hematocrit. CONCLUSION: Viscoelasticity properties, the elastic modulus G'(f) and the viscous modulus G″(f) of RBCs are associated with endurance exercise-induced anemia.

18.
Sensors (Basel) ; 17(11)2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29117140

RESUMO

The fact that piezoelectric ceramic transducer (PZT) precision drive systems in 3D printing are faced with nonlinear problems with respect to positioning, such as hysteresis and creep, has had an extremely negative impact on the precision of laser focusing systems. To eliminate the impact of PZT nonlinearity during precision drive movement, mathematical modeling and theoretical analyses of each module comprising the system were carried out in this study, a micro-displacement measurement circuit based on Position Sensitive Detector (PSD) is constructed, followed by the establishment of system closed-loop control and creep control models. An XL-80 laser interferometer (Renishaw, Wotton-under-Edge, UK) was used to measure the performance of the precision drive system, showing that system modeling and control algorithms were correct, with the requirements for precision positioning of the drive system satisfied.

19.
Virol Sin ; 32(5): 387-395, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29116592

RESUMO

Varicella-zoster virus (VZV) is a neurotropic alphaherpesvirus that causes chickenpox and shingles. ORF7 is an important virulence determinant of VZV in both human skin and nerve tissues, however, its specific function and involved molecular mechanism in VZV pathogenesis remain largely elusive. Previous yeast two-hybrid studies on intraviral protein-protein interaction network in herpesviruses have revealed that VZV ORF7 may interact with ORF53, which is a virtually unstudied but essential viral protein. The aim of this study is to identify and characterize VZV ORF53, and to investigate its relationship with ORF7. For this purpose, we prepared monoclonal antibodies against ORF53 and, for the first time, characterized it as a ~40 kDa viral protein predominantly localizing to the trans-Golgi network of the infected host cell. Next, we further confirmed the interaction between ORF7 and ORF53 by co-immunoprecipitation and co-localization studies in both plasmid-transfected and VZV-infected cells. Moreover, interestingly, we found that ORF53 lost its trans-Golgi network localization and became dispersed in the cytoplasm of host cells infected with an ORF7-deleted recombinant VZV, and thus ORF7 seems to play a role in normal subcellular localization of ORF53. Collectively, these results suggested that ORF7 and ORF53 may function as a complex during infection, which may be implicated in VZV pathogenesis.


Assuntos
Herpesvirus Humano 3/metabolismo , Proteínas Virais/metabolismo , Rede trans-Golgi/metabolismo , Imunoprecipitação , Ligação Proteica
20.
Invest Ophthalmol Vis Sci ; 58(13): 5628-5635, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29094166

RESUMO

Purpose: This study investigated the anterior ocular anatomic origin of high-order aberration (HOA) components using optical coherence tomography and a Shack-Hartmann wavefront sensor. Methods: A customized system was built to simultaneously capture images of ocular wavefront aberrations and anterior ocular biometry. Relaxed, 2-diopter (D) and 4-D accommodative states were repeatedly measured in 30 young subjects. Custom software was used to correct optical distortions and measure biometric parameters from the images. Results: The anterior ocular biometry changed during 2-D accommodation, in which central lens thickness, ciliary muscle thicknesses at 1 mm posterior to the scleral spur (CMT1), and the maximum value of ciliary muscle thickness increased significantly, whereas anterior chamber depth, CMT3, radius of anterior lens surface curvature (RAL), and radius of posterior lens surface curvature (RPL) decreased significantly. The changes in the anterior ocular parameters during 4-D accommodation were similar to those for the 2-D accommodation. \(\def\upalpha{\unicode[Times]{x3B1}}\)\(\def\upbeta{\unicode[Times]{x3B2}}\)\(\def\upgamma{\unicode[Times]{x3B3}}\)\(\def\updelta{\unicode[Times]{x3B4}}\)\(\def\upvarepsilon{\unicode[Times]{x3B5}}\)\(\def\upzeta{\unicode[Times]{x3B6}}\)\(\def\upeta{\unicode[Times]{x3B7}}\)\(\def\uptheta{\unicode[Times]{x3B8}}\)\(\def\upiota{\unicode[Times]{x3B9}}\)\(\def\upkappa{\unicode[Times]{x3BA}}\)\(\def\uplambda{\unicode[Times]{x3BB}}\)\(\def\upmu{\unicode[Times]{x3BC}}\)\(\def\upnu{\unicode[Times]{x3BD}}\)\(\def\upxi{\unicode[Times]{x3BE}}\)\(\def\upomicron{\unicode[Times]{x3BF}}\)\(\def\uppi{\unicode[Times]{x3C0}}\)\(\def\uprho{\unicode[Times]{x3C1}}\)\(\def\upsigma{\unicode[Times]{x3C3}}\)\(\def\uptau{\unicode[Times]{x3C4}}\)\(\def\upupsilon{\unicode[Times]{x3C5}}\)\(\def\upphi{\unicode[Times]{x3C6}}\)\(\def\upchi{\unicode[Times]{x3C7}}\)\(\def\uppsy{\unicode[Times]{x3C8}}\)\(\def\upomega{\unicode[Times]{x3C9}}\)\(\def\bialpha{\boldsymbol{\alpha}}\)\(\def\bibeta{\boldsymbol{\beta}}\)\(\def\bigamma{\boldsymbol{\gamma}}\)\(\def\bidelta{\boldsymbol{\delta}}\)\(\def\bivarepsilon{\boldsymbol{\varepsilon}}\)\(\def\bizeta{\boldsymbol{\zeta}}\)\(\def\bieta{\boldsymbol{\eta}}\)\(\def\bitheta{\boldsymbol{\theta}}\)\(\def\biiota{\boldsymbol{\iota}}\)\(\def\bikappa{\boldsymbol{\kappa}}\)\(\def\bilambda{\boldsymbol{\lambda}}\)\(\def\bimu{\boldsymbol{\mu}}\)\(\def\binu{\boldsymbol{\nu}}\)\(\def\bixi{\boldsymbol{\xi}}\)\(\def\biomicron{\boldsymbol{\micron}}\)\(\def\bipi{\boldsymbol{\pi}}\)\(\def\birho{\boldsymbol{\rho}}\)\(\def\bisigma{\boldsymbol{\sigma}}\)\(\def\bitau{\boldsymbol{\tau}}\)\(\def\biupsilon{\boldsymbol{\upsilon}}\)\(\def\biphi{\boldsymbol{\phi}}\)\(\def\bichi{\boldsymbol{\chi}}\)\(\def\bipsy{\boldsymbol{\psy}}\)\(\def\biomega{\boldsymbol{\omega}}\)\(\def\bupalpha{\unicode[Times]{x1D6C2}}\)\(\def\bupbeta{\unicode[Times]{x1D6C3}}\)\(\def\bupgamma{\unicode[Times]{x1D6C4}}\)\(\def\bupdelta{\unicode[Times]{x1D6C5}}\)\(\def\bupepsilon{\unicode[Times]{x1D6C6}}\)\(\def\bupvarepsilon{\unicode[Times]{x1D6DC}}\)\(\def\bupzeta{\unicode[Times]{x1D6C7}}\)\(\def\bupeta{\unicode[Times]{x1D6C8}}\)\(\def\buptheta{\unicode[Times]{x1D6C9}}\)\(\def\bupiota{\unicode[Times]{x1D6CA}}\)\(\def\bupkappa{\unicode[Times]{x1D6CB}}\)\(\def\buplambda{\unicode[Times]{x1D6CC}}\)\(\def\bupmu{\unicode[Times]{x1D6CD}}\)\(\def\bupnu{\unicode[Times]{x1D6CE}}\)\(\def\bupxi{\unicode[Times]{x1D6CF}}\)\(\def\bupomicron{\unicode[Times]{x1D6D0}}\)\(\def\buppi{\unicode[Times]{x1D6D1}}\)\(\def\buprho{\unicode[Times]{x1D6D2}}\)\(\def\bupsigma{\unicode[Times]{x1D6D4}}\)\(\def\buptau{\unicode[Times]{x1D6D5}}\)\(\def\bupupsilon{\unicode[Times]{x1D6D6}}\)\(\def\bupphi{\unicode[Times]{x1D6D7}}\)\(\def\bupchi{\unicode[Times]{x1D6D8}}\)\(\def\buppsy{\unicode[Times]{x1D6D9}}\)\(\def\bupomega{\unicode[Times]{x1D6DA}}\)\(\def\bupvartheta{\unicode[Times]{x1D6DD}}\)\(\def\bGamma{\bf{\Gamma}}\)\(\def\bDelta{\bf{\Delta}}\)\(\def\bTheta{\bf{\Theta}}\)\(\def\bLambda{\bf{\Lambda}}\)\(\def\bXi{\bf{\Xi}}\)\(\def\bPi{\bf{\Pi}}\)\(\def\bSigma{\bf{\Sigma}}\)\(\def\bUpsilon{\bf{\Upsilon}}\)\(\def\bPhi{\bf{\Phi}}\)\(\def\bPsi{\bf{\Psi}}\)\(\def\bOmega{\bf{\Omega}}\)\(\def\iGamma{\unicode[Times]{x1D6E4}}\)\(\def\iDelta{\unicode[Times]{x1D6E5}}\)\(\def\iTheta{\unicode[Times]{x1D6E9}}\)\(\def\iLambda{\unicode[Times]{x1D6EC}}\)\(\def\iXi{\unicode[Times]{x1D6EF}}\)\(\def\iPi{\unicode[Times]{x1D6F1}}\)\(\def\iSigma{\unicode[Times]{x1D6F4}}\)\(\def\iUpsilon{\unicode[Times]{x1D6F6}}\)\(\def\iPhi{\unicode[Times]{x1D6F7}}\)\(\def\iPsi{\unicode[Times]{x1D6F9}}\)\(\def\iOmega{\unicode[Times]{x1D6FA}}\)\(\def\biGamma{\unicode[Times]{x1D71E}}\)\(\def\biDelta{\unicode[Times]{x1D71F}}\)\(\def\biTheta{\unicode[Times]{x1D723}}\)\(\def\biLambda{\unicode[Times]{x1D726}}\)\(\def\biXi{\unicode[Times]{x1D729}}\)\(\def\biPi{\unicode[Times]{x1D72B}}\)\(\def\biSigma{\unicode[Times]{x1D72E}}\)\(\def\biUpsilon{\unicode[Times]{x1D730}}\)\(\def\biPhi{\unicode[Times]{x1D731}}\)\(\def\biPsi{\unicode[Times]{x1D733}}\)\(\def\biOmega{\unicode[Times]{x1D734}}\)\({\rm{Z}}_4^0\) decreased significantly during 2-D accommodation, and \({\rm{Z}}_3^{ - 1}\), \({\rm{Z}}_3^1\), \({\rm{Z}}_4^0\), and \({\rm{Z}}_6^0\) shifted to negative values during 4-D accommodation. The change in \({\rm{Z}}_4^0\) negatively correlated with those in CMT1, and the negative change in \({\rm{Z}}_3^1\) correlated with changes in RAL and CMT1. Conclusions: HOA components altered during step-controlled accommodative stimuli. Ciliary muscle first contracted during stepwise accommodation, which may directly contribute to the reduction of spherical aberration (SA). The lens morphology was then altered, and the change in anterior lens surface curvature was related to the variation of coma.


Assuntos
Acomodação Ocular/fisiologia , Segmento Anterior do Olho/anatomia & histologia , Biometria/métodos , Refração Ocular/fisiologia , Adulto , Feminino , Voluntários Saudáveis , Humanos , Masculino , Tomografia de Coerência Óptica/métodos
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