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2.
JAMA Ophthalmol ; 141(10): 990-999, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37261839

RESUMO

Importance: The global prevalence of myopia is predicted to approach 50% by 2050, increasing the risk of visual impairment later in life. No pharmacologic therapy is approved for treating childhood myopia progression. Objective: To assess the safety and efficacy of NVK002 (Vyluma), a novel, preservative-free, 0.01% and 0.02% low-dose atropine formulation for treating myopia progression. Design, Setting, and Participants: This was a double-masked, placebo-controlled, parallel-group, randomized phase 3 clinical trial conducted from November 20, 2017, through August 22, 2022, of placebo vs low-dose atropine, 0.01% and 0.02% (2:2:3 ratio). Participants were recruited from 26 clinical sites in North America and 5 countries in Europe. Enrolled participants were 3 to 16 years of age with -0.50 diopter (D) to -6.00 D spherical equivalent refractive error (SER) and no worse than -1.50 D astigmatism. Interventions: Once-daily placebo, low-dose atropine, 0.01%, or low-dose atropine, 0.02%, eye drops for 36 months. Main Outcomes and Measures: The primary, prespecified end point was the proportion of participants' eyes responding to 0.02% atropine vs placebo therapy (<0.50 D myopia progression at 36 months [responder analysis]). Secondary efficacy end points included responder analysis for atropine, 0.01%, and mean change from baseline in SER and axial length at month 36 in a modified intention-to-treat population (mITT; participants 6-10 years of age at baseline). Safety measurements for treated participants (3-16 years of age) were reported. Results: A total of 576 participants were randomly assigned to treatment groups. Of these, 573 participants (99.5%; mean [SD] age, 8.9 [2.0] years; 315 female [54.7%]) received trial treatment (3 participants who were randomized did not receive trial drug) and were included in the safety set. The 489 participants (84.9%) who were 6 to 10 years of age at randomization composed the mITT set. At month 36, compared with placebo, low-dose atropine, 0.02%, did not significantly increase the responder proportion (odds ratio [OR], 1.77; 95% CI, 0.50-6.26; P = .37) or slow mean SER progression (least squares mean [LSM] difference, 0.10 D; 95% CI, -0.02 D to 0.22 D; P = .10) but did slow mean axial elongation (LSM difference, -0.08 mm; 95% CI, -0.13 mm to -0.02 mm; P = .005); however, at month 36, compared with placebo, low-dose atropine, 0.01%, significantly increased the responder proportion (OR, 4.54; 95% CI, 1.15-17.97; P = .03), slowed mean SER progression (LSM difference, 0.24 D; 95% CI, 0.11 D-0.37 D; P < .001), and slowed axial elongation (LSM difference, -0.13 mm; 95% CI, -0.19 mm to -0.07 mm; P < .001). There were no serious ocular adverse events and few serious nonocular events; none was judged as associated with atropine. Conclusions and Relevance: This randomized clinical trial found that 0.02% atropine did not significantly increase the proportion of participants' eyes responding to therapy but suggested efficacy for 0.01% atropine across all 3 main end points compared with placebo. The efficacy and safety observed suggest that low-dose atropine may provide a treatment option for childhood myopia progression. Trial Registration: ClinicalTrials.gov Identifier: NCT03350620.

4.
Semin Ophthalmol ; 27(5-6): 100-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23163261

RESUMO

Intraoperative wavefront aberrometry is a relatively new technology that aims to improve refractive outcomes following cataract surgery by optimizing the spherical power of the intraocular lens implant or calculating the appropriate axis and power of toric lenses during cataract surgery in an aphakic state. This article reviews the literature on intraoperative wavefront aberrometry and provides a critical assessment of the benefits and shortcomings of that technology.


Assuntos
Aberrometria/métodos , Extração de Catarata , Aberrações de Frente de Onda da Córnea/diagnóstico , Humanos , Período Intraoperatório
5.
J Am Chem Soc ; 134(21): 8848-55, 2012 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-22385538

RESUMO

We report a novel nanoparticulate drug delivery system that undergoes reversible volume change from 150 to 40 nm upon phototriggering with UV light. The volume change of these monodisperse nanoparticles comprising spiropyran, which undergoes reversible photoisomerization, and PEGylated lipid enables repetitive dosing from a single administration and enhances tissue penetration. The photoswitching allows particles to fluoresce and release drugs inside cells when illuminated with UV light. The mechanism of the light-induced size switching and triggered-release is studied. These particles provide spatiotemporal control of drug release and enhanced tissue penetration, useful properties in many disease states including cancer.


Assuntos
Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Luz , Nanopartículas/química , Linhagem Celular Tumoral , Colágeno/metabolismo , Córnea/metabolismo , Córnea/efeitos da radiação , Difusão , Humanos , Modelos Moleculares , Conformação Molecular , Tamanho da Partícula , Permeabilidade/efeitos da radiação , Propriedades de Superfície
6.
Invest Ophthalmol Vis Sci ; 52(9): 6743-8, 2011 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-21685337

RESUMO

PURPOSE: To explore the correlation between outer retinal substructures and visual acuity in dry age-related macular degeneration (AMD). METHODS: Analysis of spectral domain optical coherence tomography datasets from 100 eyes of 100 consecutive patients with dry AMD was performed. The internal limiting membrane, outer nuclear layer (ONL), external limiting membrane (ELM), inner segment-outer segment (IS-OS) junction, outer photoreceptor border, inner and outer retinal pigment epithelium (RPE) borders, and Bruch's membrane, were manually segmented by Doheny Image Reading Center (DIRC) graders. Areas, thicknesses, and volumes of RPE, IS, OS, ONL, and the total retina in the foveal central subfield were correlated with the logarithm of minimal angle of resolution (logMAR) visual acuity using univariable and multivariable regression analysis. RESULTS: The visual acuity in this group ranged from logMAR 0 to 1.3 with a mean of 0.23. Areas, thicknesses, and volumes of ONL, IS and OS, thicknesses of total retinal and RPE, and intensities of IS, OS, and RPE, showed statistically significant association (P < 0.05) with logMAR best corrected visual acuity. The highest correlations were observed for the ONL (thickness: r = -0.49, volume: -0.47, area: -0.50) and photoreceptor IS (thickness: -0.59, area: -0.63, volume: -0.53). The model with the highest correlation in this study included thicknesses of ONL, IS, OS and RPE, as well as area of ONL, IS, OS, RPE, and intensity of RPE. CONCLUSIONS. Although integrity of outer retinal substructures in the foveal central subfield correlates with visual acuity in the eyes of patients with dry AMD, the correlation is only moderate and does not fully explain the variability in acuity in these cases.


Assuntos
Fóvea Central/patologia , Fóvea Central/fisiopatologia , Degeneração Macular/patologia , Degeneração Macular/fisiopatologia , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Regressão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Tomografia de Coerência Óptica/normas
7.
No Shinkei Geka ; 32(8): 827-34, 2004 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-15478649

RESUMO

Cancers are formed by heterogeneous cell types from immature highly proliferative cells to lineage-committed differentiated cells. Transplantation studies have suggested the existence of "cancer stem cells", individual cells capable of producing an entire tumor. Recent advances in stem cell research have allowed for the demonstration of the existence of cancer stem cells in acute myeloid leukemia, breast cancer, and, most recently, in pediatric brain tumors. Each of these has some similarities with the normal stem cells in the corresponding organs. For example, leukemia stem cells express some, but not all, markers of hematopoietic stem cells. Regarding pediatric brain tumors, putative cancer stem cells were identified from medulloblastoma and also from glioma. These tumor-derived cells self-renew under clonal conditions, and differentiate into neurons and glia as well as into abnormal cells with mixed phenotypes. Interestingly, the tumor stem/progenitors, enriched in culture, maintained proliferation after 4 weeks from transplantation into neonatal rat brain. In this review, we discuss the difference as well as the similarity between tumor and normal stem cells, and also the possible clinical implication of cancer stem cells.


Assuntos
Neoplasias Encefálicas/patologia , Células-Tronco Neoplásicas/patologia , Animais , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Proteínas de Ciclo Celular , Transformação Celular Neoplásica , Criança , Proteínas de Ligação a DNA , Humanos , Proteínas Nucleares , PTEN Fosfo-Hidrolase , Monoéster Fosfórico Hidrolases , Complexo Repressor Polycomb 1 , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas , Proteínas Proto-Oncogênicas c-akt , Ratos , Proteínas Repressoras , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Transativadores , Proteínas Supressoras de Tumor
8.
Proc Natl Acad Sci U S A ; 100(25): 15178-83, 2003 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-14645703

RESUMO

Pediatric brain tumors are significant causes of morbidity and mortality. It has been hypothesized that they derive from self-renewing multipotent neural stem cells. Here, we tested whether different pediatric brain tumors, including medulloblastomas and gliomas, contain cells with properties similar to neural stem cells. We find that tumor-derived progenitors form neurospheres that can be passaged at clonal density and are able to self-renew. Under conditions promoting differentiation, individual cells are multipotent, giving rise to both neurons and glia, in proportions that reflect the tumor of origin. Unlike normal neural stem cells, however, tumor-derived progenitors have an unusual capacity to proliferate and sometimes differentiate into abnormal cells with multiple differentiation markers. Gene expression analysis reveals that both whole tumors and tumor-derived neurospheres express many genes characteristic of neural and other stem cells, including CD133, Sox2, musashi-1, bmi-1, maternal embryonic leucine zipper kinase, and phosphoserine phosphatase, with variation from tumor to tumor. After grafting to neonatal rat brains, tumor-derived neurosphere cells migrate, produce neurons and glia, and continue to proliferate for more than 4 weeks. The results show that pediatric brain tumors contain neural stem-like cells with altered characteristics that may contribute to tumorigenesis. This finding may have important implications for treatment by means of specific targeting of stem-like cells within brain tumors.


Assuntos
Neoplasias Encefálicas/patologia , Neuroglia/patologia , Neurônios/patologia , Células-Tronco/patologia , Antígeno AC133 , Animais , Antígenos CD , Encéfalo/patologia , Bromodesoxiuridina/farmacologia , Diferenciação Celular , Criança , Corantes/farmacologia , Proteínas de Ligação a DNA/biossíntese , Regulação Neoplásica da Expressão Gênica , Glicoproteínas/biossíntese , Proteínas HMGB , Humanos , Imuno-Histoquímica , Lactente , Transplante de Neoplasias , Proteínas do Tecido Nervoso/biossíntese , Proteínas Nucleares/biossíntese , Peptídeos , Monoéster Fosfórico Hidrolases/biossíntese , Proteínas de Ligação a RNA/biossíntese , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1 , Fatores de Transcrição
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