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Two-dimensional (2D)/three-dimensional (3D) halide perovskite heterostructures have been extensively studied for their ability to combine the outstanding long-term stability of 2D perovskites with the superb optoelectronic properties of 3D perovskites. While current studies mostly focus on vertically stacked 2D/3D perovskite heterostructures, a theoretical understanding regarding the optoelectronic properties of 2D/3D perovskite lateral heterostructures is still lacking. Herein, we construct a series of 2D/3D perovskite lateral heterostructures to study their optoelectronic properties and interfacial charge transfer using density functional theory (DFT) calculations. We find that the band alignments of 2D/3D heterostructures can be regulated by varying the quantum-well thickness of 2D perovskites. Moreover, decreasing the 2D component ratio in 2D/3D heterostructures can be favorable to form type-I band alignment, whereas a large component ratio of 2D perovskites tends to form type-II band alignment. We can improve the amount of charge transfer at the 2D/3D perovskite interfaces and the light absorption of 2D perovskites by increasing quantum-well thickness. These present findings can provide a clear designing principle for achieving 3D/2D perovskite lateral heterostructures with tunable optoelectronic properties.
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SIGNIFICANCE: Binocular treatment for unilateral amblyopia is an emerging treatment that requires evaluation through a randomized clinical trial. PURPOSE: This study aimed to compare change in amblyopic-eye visual acuity (VA) in children aged 4 to 6 years treated with the dichoptic binocular iPad (Apple, Cupertino, CA) game, Dig Rush (not yet commercially available; Ubisoft, Montreal, Canada), plus continued spectacle correction versus continued spectacle correction alone. METHODS: Children (mean age, 5.7 years) were randomly assigned to home treatment for 8 weeks with the iPad game (prescribed 1 h/d, 5 d/wk [n = 92], or continued spectacle correction alone [n = 90]) in a multicenter randomized clinical trial. Before enrollment, children wearing spectacles were required to have at least 16 weeks of wear or no improvement in amblyopic-eye VA (<0.1 logMAR) for at least 8 weeks. Outcome was change in amblyopic-eye VA from baseline to 4 weeks (primary) and 8 weeks (secondary) assessed by masked examiner. RESULTS: A total of 182 children with anisometropic (63%), strabismic (16%; <5∆ near, simultaneous prism and cover test), or combined-mechanism (20%) amblyopia (20/40 to 20/200; mean, 20/63) were enrolled. After 4 weeks, mean amblyopic VA improved by 1.1 logMAR lines with binocular treatment and 0.6 logMAR lines with spectacles alone (adjusted difference, 0.5 lines; 95.1% confidence interval [CI], 0.1 to 0.9). After 8 weeks, results (binocular treatment: mean amblyopic-eye VA improvement, 1.3 vs. 1.0 logMAR lines with spectacles alone; adjusted difference, 0.3 lines; 98.4% CI, -0.2 to 0.8 lines) were inconclusive because the CI included both zero and the pre-defined difference in mean VA change of 0.75 logMAR lines. CONCLUSIONS: In 4- to 6-year-old children with amblyopia, binocular Dig Rush treatment resulted in greater improvement in amblyopic-eye VA for 4 weeks but not 8 weeks. Future work is required to determine if modifications to the contrast increment algorithm or other aspects of the game or its implementation could enhance the treatment effect.
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Ambliopía , Ambliopía/terapia , Niño , Preescolar , Anteojos , Estudios de Seguimiento , Humanos , Privación Sensorial , Resultado del Tratamiento , Visión BinocularRESUMEN
PURPOSE: Intravitreal bevacizumab is increasingly used to treat severe retinopathy of prematurity (ROP), but it enters the bloodstream, and there is concern that it may alter development of other organs. Previously we reported short-term outcomes of 61 infants enrolled in a dose de-escalation study, and we report the late recurrences and additional treatments. DESIGN: Masked, multicenter, dose de-escalation study. PARTICIPANTS: A total of 61 premature infants with type 1 ROP. METHODS: If type 1 ROP was bilateral at enrollment, then the study eye was randomly selected. In the study eye, bevacizumab intravitreal injections were given at de-escalating doses of 0.25 mg, 0.125 mg, 0.063 mg, or 0.031 mg; if needed, fellow eyes received 1 dose level higher: 0.625 mg, 0.25 mg, 0.125 mg, or 0.063 mg, respectively. After 4 weeks, additional treatment was at the discretion of the investigator. MAIN OUTCOME MEASURES: Early and late ROP recurrences, additional treatments, and structural outcomes after 6 months. RESULTS: Of 61 study eyes, 25 (41%; 95% confidence interval [CI], 29%-54%) received additional treatment: 3 (5%; 95% CI, 1%-14%) for early failure (within 4 weeks), 11 (18%; 95% CI, 9%-30%) for late recurrence of ROP (after 4 weeks), and 11 (18%; 95% CI, 9%-30%) for persistent avascular retina. Re-treatment for early failure or late recurrence occurred in 2 of 11 eyes (18%; 95% CI, 2%-52%) treated with 0.25 mg, 4 of 16 eyes (25%; 95% CI, 7%-52%) treated with 0.125 mg, 8 of 24 eyes (33%; 95% CI, 16%-55%) treated with 0.063 mg, and 0 (0%; 95% CI, 0%-31%) of 10 eyes treated with 0.031 mg. By 6 months corrected age, 56 of 61 study eyes had regression of ROP with normal posterior poles, 1 study eye had developed a Stage 5 retinal detachment, and 4 infants had died of preexisting medical conditions. CONCLUSIONS: Retinal structural outcomes are very good after low-dose bevacizumab treatment for ROP, although many eyes received additional treatment.
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Inhibidores de la Angiogénesis/administración & dosificación , Bevacizumab/administración & dosificación , Retinopatía de la Prematuridad/tratamiento farmacológico , Terapia Combinada , Método Doble Ciego , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido de Bajo Peso , Recién Nacido , Recien Nacido Prematuro , Inyecciones Intravítreas , Coagulación con Láser , Masculino , Recurrencia , Retina/fisiopatología , Retinopatía de la Prematuridad/diagnóstico , Retinopatía de la Prematuridad/fisiopatología , Retratamiento , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidoresRESUMEN
PURPOSE: We conducted a cross-sectional study to test the hypothesis that the structural contributions to myopia in preterm and full-term born children are different. METHODS: In this study, 93 children ranging from ages 2 to 13 who had myopia ≥ -3 diopters in at least one eye were examined with A-scans. The following data was collected and analyzed: history of birth, refractive error (RE), cornea thickness (CT) and average corneal curvature (AVK), depth of anterior chamber (ACD), lens thickness (LT), and axial length (AL) of the eye. RESULTS: Eyes were tested and categorized into four groups: myopic eyes in full-term children (group 1), myopic eyes in premature children (group 2), non-myopic eyes in full-term children (group 3), and non-myopic eyes in preterm children (group 4). The RE were similar between group 1 and group2, and between group 3 and group 4. Myopic eyes in group 2 had higher AVK as compared to group 3; 45.4 ± 0.4 D vs. 43.5 ± 0.7 D, p = 0.008. The ACD in group 2 was shallower than that in group 1 (2.5 ± 0.5 vs. 3.2 ± 0.3, p = 0.01). The LT measurements in group 2 were thicker than those in group 1 (mean LT = 4.9 ± 1.0 vs 4.1 ± 0.3 mm, p = 0.001, respectively). Finally, AL of myopic eyes in group 1 was longer than that of group 2, p = 0.01. CONCLUSION: These results suggest that increased axial length plays an important role in myopia in full-term children, whereas corneal curvature and lens thickness are major contributors to myopia in preterm children.
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Longitud Axial del Ojo/fisiopatología , Miopía/fisiopatología , Nacimiento Prematuro , Retinopatía de la Prematuridad/fisiopatología , Nacimiento a Término , Adolescente , Biometría , Niño , Preescolar , Estudios Transversales , Femenino , Edad Gestacional , Humanos , Masculino , Estudios ProspectivosRESUMEN
Lens induction is a classical embryologic model to study cell fate determination. It has been proposed earlier that specific changes in core histone modifications accompany the process of cell fate specification and determination. The lysine acetyltransferases CBP and p300 function as principal enzymes that modify core histones to facilitate specific gene expression. Herein, we performed conditional inactivation of both CBP and p300 in the ectodermal cells that give rise to the lens placode. Inactivation of both CBP and p300 resulted in the dramatic discontinuation of all aspects of lens specification and organogenesis, resulting in aphakia. The CBP/p300(-/-) ectodermal cells are viable and not prone to apoptosis. These cells showed reduced expression of Six3 and Sox2, while expression of Pax6 was not upregulated, indicating discontinuation of lens induction. Consequently, expression of αB- and αA-crystallins was not initiated. Mutant ectoderm exhibited markedly reduced levels of histone H3 K18 and K27 acetylation, subtly increased H3 K27me3 and unaltered overall levels of H3 K9ac and H3 K4me3. Our data demonstrate that CBP and p300 are required to establish lens cell-type identity during lens induction, and suggest that posttranslational histone modifications are integral to normal cell fate determination in the mammalian lens.
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Proteína de Unión a CREB/fisiología , Proteína p300 Asociada a E1A/fisiología , Histonas/metabolismo , Cristalino/embriología , Acetilación , Animales , Apoptosis , Proteína de Unión a CREB/genética , Proteína p300 Asociada a E1A/genética , Inducción Embrionaria , Expresión Génica , Cristalino/anatomía & histología , Cristalino/enzimología , Ratones , Mutación , Procesamiento Proteico-Postraduccional , Fase SRESUMEN
BACKGROUND: No study has examined the association between per- and polyfluoroalkyl substances (PFAS) exposure and chronic obstructive pulmonary disease (COPD) risk. This study aims to explore this relationship. METHODS: This study enrolled 4541 individuals who had available data on PFAS, COPD, and covariates from NHANES 2007-2018. Serum PFAS including perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA), perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS) were analyzed, because of high detective rates. Considering the skew distribution of PFAS levels, the natural logarithm-transformed PFAS (Ln-PFAS) was used. Logistic regression analysis, restricted cubic spline (RCS), and weighted quantile sum (WQS) regression were performed to explore the single, nonlinear, and mixed effects. A mediating analysis was used to evaluate the mediated effects of albumin. RESULTS: Individuals with COPD had higher levels of PFHxS, PFNA, PFOA, and PFOS compared to those without COPD. Ln-PFNA (OR males: 1.92, 95 % CI:1.31 to 2.80, P: <0.001; OR females: 1.07, 95 % CI: 0.81 to 1.40, P: 0.636) and ln-PFOA (OR males: 2.17, 95 % CI:1.38 to 3.41, P: <0.001; OR females: 1.49, 95 % CI: 1.08 to 2.05, P: 0.016) were associated with COPD risk especially in males. The interaction between PFNA exposure and sex on COPD risk was significant (P interaction: <0.001). The RCS curve demonstrated the nonlinear relationship between the ln-PFOA (P nonlinear:0.001), ln-PFNA (P nonlinear:0.045), and COPD risk in males. WQS analysis showed mixed PFAS exposure was correlated with COPD risk in males (OR: 1.44, 95 % CI:1.18 to 1.75, P: <0.001). Albumin mediated the relationship between PFOA and COPD (mediated proportion: -17.94 %). CONCLUSION: This study concludes PFOA and PFNA are linked to a higher COPD risk in males, and serum albumin plays a mediating role in the relationship between PFOA and COPD. Thess findings are beneficial for the prevention of COPD. Further studies are required to explore potential mechanisms.
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Ácidos Alcanesulfónicos , Caprilatos , Contaminantes Ambientales , Ácidos Grasos , Fluorocarburos , Enfermedad Pulmonar Obstructiva Crónica , Masculino , Femenino , Humanos , Encuestas Nutricionales , Albúmina Sérica , Prevalencia , Alcanosulfonatos , Enfermedad Pulmonar Obstructiva Crónica/inducido químicamente , Enfermedad Pulmonar Obstructiva Crónica/epidemiologíaRESUMEN
The YOLOv4 approach has gained significant popularity in industrial object detection due to its impressive real-time processing speed and relatively favorable accuracy. However, it has been observed that YOLOv4 faces challenges in accurately detecting small objects. Its bounding box regression strategy is rigid and fails to effectively leverage the asymmetric characteristics of objects, limiting its ability to enhance object detection accuracy. This paper proposes an enhanced version of YOLOv4 called KR-AL-YOLO (keypoint regression strategy and angle loss based YOLOv4). The KR-AL-YOLO approach introduces two customized modules: an keypoint regression strategy and an angle-loss function. These modules contribute to improving the algorithm's detection accuracy by enabling more precise localization of objects. Additionally, KR-AL-YOLO adopts an improved feature fusion technique, which facilitates enhanced information flow within the network, thereby further enhancing accuracy performance. Experimental evaluations conducted on the COCO2017 dataset demonstrate the effectiveness of the proposed method. KR-AL-YOLO achieves an average precision of 45.6%, surpassing both YOLOv4 and certain previously developed one-stage detectors. The utilization of keypoint regression strategy and the incorporation of robust feature fusion contribute to superior object detection accuracy in KR-AL-YOLO compared to YOLOv4.
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BACKGROUND: Ureaplasma causes sepsis in human neonates. Although erythromycin has been the standard treatment, it is not always effective. No published reports have evaluated Ureaplasma sepsis in a neonatal model. We hypothesized that appropriate antibiotic treatment improves Ureaplasma sepsis in a neonatal mouse model. METHODS: Two ATCC strains and two clinical strains of Ureaplasma were evaluated in vitro for antibiotic minimum inhibitory concentration (MIC). In addition, FVB albino mice pups infected with Ureaplasma were randomly assigned to saline, erythromycin, or azithromycin therapy and survival, quantitative blood culture, and growth were evaluated. RESULTS: MICs ranged from 0.125 to 62.5 µg/ml and 0.25 to 1.0 µg/ml for erythromycin and azithromycin, respectively. The infecting strain and antibiotic selected for treatment appeared to affect survival and bacteremia, but only the infecting strain affected growth. Azithromycin improved survival and bacteremia against each strain, whereas erythromycin was effective against only one of four strains. CONCLUSION: We have established a neonatal model of Ureaplasma sepsis and observed that treatment outcome is related to infecting strain and antibiotic treatment. We speculate that appropriate antibiotic selection and dosing are required for effective treatment of Ureaplasma sepsis in neonates, and this model could be used to further evaluate these relationships.
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Antibacterianos/farmacología , Azitromicina/farmacología , Eritromicina/farmacología , Sepsis/tratamiento farmacológico , Infecciones por Ureaplasma/tratamiento farmacológico , Ureaplasma/efectos de los fármacos , Animales , Animales Recién Nacidos , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Embarazo , Sepsis/diagnóstico , Sepsis/microbiología , Ureaplasma/clasificación , Ureaplasma/crecimiento & desarrollo , Infecciones por Ureaplasma/diagnóstico , Infecciones por Ureaplasma/microbiología , Ureaplasma urealyticum/efectos de los fármacosRESUMEN
PURPOSE: To assess the impact of refractive error correction from photorefractive keratectomy on development in children with severe isoametropia, subnormal visual acuity, and intellectual disability unable to use refraction correction. DESIGN: Prospective noncomparative interventional case series. METHODS: Before and after photorefractive keratometry (PRK), subjects who had plateaued developmentally for 18 or more months were assessed using a battery of developmental tests. The primary outcome measure was the change in the developmental quotient (DQ) 6 months after PRK. Secondary outcomes were the change in the DQ, uncorrected visual acuity, cycloplegic refraction, and corneal status 12, 24, and 36 months after PRK. RESULTS: Sixteen subjects aged 2 to 8 years were included. Twelve were highly myopic (mean, -9.69 ± 3.82 diopters [D]), 3 highly hyperopic (mean, +5.75 ± 0.59 D) and 1 highly astigmatic (mean, +3.50 D). Six months after PRK, the DQ significantly improved for expressive communication (mean, 4.51 ± 2.27 months; P = .04), interpersonal relationships (mean, 9.45 ± 4.18 months; P = .02) and coping (mean, 6.44 ± 2.10 months; P = .05). Twelve months after PRK, the DQ significantly improved for receptive communication (8.04 ± 1.80 months; P < .001), expressive communication (6.99 ± 2.27 months; P < .05), written communication (9.28 ± 3.72 months; P < .04), domestic skills (6.50 ± 2.43 months; P < .03), interpersonal relationships (10.57 ± 4.17 months; P < .02), and coping (8.41 ± 3.25 months; P < .5). CONCLUSIONS: PRK significantly improves developmental abilities of children with intellectual disability, severe isoametropia, and previously plateaued development, in addition to improving visual acuity and refractive error.
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Discapacidad Intelectual , Miopía , Queratectomía Fotorrefractiva , Niño , Preescolar , Córnea , Humanos , Láseres de Excímeros/uso terapéutico , Miopía/cirugía , Estudios Prospectivos , Refracción Ocular , Resultado del TratamientoRESUMEN
Importance: Intravitreal bevacizumab effectively treats severe retinopathy of prematurity (ROP), but it enters the bloodstream and may reduce serum vascular endothelial growth factor (VEGF), potentially causing detrimental effects on developing organs in the premature infant. Objective: To evaluate the association of intravitreal bevacizumab with plasma bevacizumab and VEGF concentrations at 2 and 4 weeks after predefined, de-escalating doses of intravitreal bevacizumab were administered to infants with severe ROP. Design, Setting, and Participants: This phase 1 dose de-escalation case series study was conducted at 10 US hospitals of ophthalmology institutions from May 21, 2015, to May 7, 2019. Blood samples were collected 2 and 4 weeks after intravitreal bevacizumab injection. Participants included 83 premature infants with type 1 ROP in 1 or both eyes and no previous ROP treatment. Data were analyzed from April 2017 to August 2021. Interventions: Study eyes received a single bevacizumab injection of 0.250 mg, 0.125 mg, 0.063 mg, 0.031 mg, 0.016 mg, 0.008 mg, 0.004 mg, or 0.002 mg. When the fellow eye required treatment, one dose higher was administered. Total dose administered at baseline was defined as the sum of doses given to each eye within 3 days of initial study-eye injection. Main Outcomes and Measures: Plasma bevacizumab concentration at 2 and 4 weeks after injection and the percentage change in plasma VEGF concentrations from pretreatment levels. Results: A total of 83 infants (mean [SD] age, 25 [2] weeks; 48 boys [58%]) were included in this study. Higher doses of bevacizumab administered at baseline were associated with higher plasma bevacizumab concentrations at 2 weeks (ρ, 0.53; 95% CI, 0.31-0.70) and 4 weeks (ρ, 0.44; 95% CI, 0.18-0.64). Plasma VEGF concentrations decreased by 50% or more from pretreatment levels in 40 of 66 infants (61%) at 2 weeks and 31 of 61 infants (51%) at 4 weeks, but no association was observed between the total dose of bevacizumab administered at baseline and percentage change in plasma VEGF concentrations 2 weeks (ρ, -0.04; 95% CI, -0.28 to 0.20) or 4 weeks (ρ, -0.17; 95% CI, -0.41 to 0.08) after injection. Conclusions and Relevance: Results of this phase 1 dose de-escalation case series study revealed that bevacizumab doses as low as 0.002 mg were associated with reduced plasma VEGF levels for most infants at 2 and 4 weeks after intravitreal administration; however, no association was observed between total bevacizumab dose administered and reductions in plasma VEGF levels from preinjection to 2 weeks or 4 weeks. Additional studies are needed to evaluate the long-term effects of low-dose bevacizumab on neurodevelopment and retinal structure.
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Retinopatía de la Prematuridad , Factor A de Crecimiento Endotelial Vascular , Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Inyecciones Intravítreas , Masculino , Retinopatía de la Prematuridad/diagnóstico , Retinopatía de la Prematuridad/tratamiento farmacológicoRESUMEN
The ocular environment has been shown to induce tolerance to locally administered antigens. We therefore investigated whether there was a systemic immune response against adenoviral vectors injected into the vitreous of retinoblastoma patients enrolled in a phase 1 clinical trial of adenoviral-mediated thymidine kinase gene transfer. Sections of enucleated eyes were immunostained with antibodies against inflammatory cells. A trend toward increasing numbers of plasma cells, T cells, macrophages, and antigen-presenting cells was observed in the injected subjects' eyes, but systemically, there was no significant increase in the number of adenovirus-specific cytotoxic T lymphocytes (CTLs) or in adenovirus neutralizing antibodies. Therefore, in contrast to studies showing significant immunogenicity of Ad-RSVtk following injection into extraocular tumors, injection into the eye produces only a mild local inflammatory response without evidence of systemic cellular or humoral immune responses to adenovirus.
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Adenoviridae/genética , Adenoviridae/inmunología , Vectores Genéticos/genética , Vectores Genéticos/inmunología , Retinoblastoma/inmunología , Retinoblastoma/terapia , Células Presentadoras de Antígenos/inmunología , Ojo/inmunología , Ojo/metabolismo , Terapia Genética/métodos , Humanos , Inmunohistoquímica , Técnicas In Vitro , Macrófagos/inmunología , Retinoblastoma/genética , Retinoblastoma/metabolismo , Linfocitos T/inmunología , Timidina Quinasa/genética , Timidina Quinasa/metabolismoRESUMEN
IMPORTANCE: This is the first large-scale randomized clinical trial evaluating the effectiveness and safety of overminus spectacle therapy for treatment of intermittent exotropia (IXT). OBJECTIVE: To evaluate the effectiveness of overminus spectacles to improve distance IXT control. DESIGN, SETTING, AND PARTICIPANTS: This randomized clinical trial conducted at 56 clinical sites between January 2017 and January 2019 associated with the Pediatric Eye Disease Investigator Group enrolled 386 children aged 3 to 10 years with IXT, a mean distance control score of 2 or worse, and a refractive error between 1.00 and -6.00 diopters (D). Data analysis was performed from February to December 2020. INTERVENTIONS: Participants were randomly assigned to overminus spectacle therapy (-2.50 D for 12 months, then -1.25 D for 3 months, followed by nonoverminus spectacles for 3 months) or to nonoverminus spectacle use. MAIN OUTCOMES AND MEASURES: Primary and secondary outcomes were the mean distance IXT control scores of participants examined after 12 months of treatment (primary outcome) and at 18 months (3 months after treatment ended) assessed by an examiner masked to treatment group. Change in refractive error from baseline to 12 months was compared between groups. Analyses were performed using the intention-to-treat population. RESULTS: The mean (SD) age of 196 participants randomized to overminus therapy and 190 participants randomized to nonoverminus treatment was 6.3 (2.1) years, and 226 (59%) were female. Mean distance control at 12 months was better in participants treated with overminus spectacles than with nonoverminus spectacles (1.8 vs 2.8 points; adjusted difference, -0.8; 95% CI, -1.0 to -0.5; P < .001). At 18 months, there was little or no difference in mean distance control between overminus and nonoverminus groups (2.4 vs 2.7 points; adjusted difference, -0.2; 95% CI, -0.5 to 0.04; P = .09). Myopic shift from baseline to 12 months was greater in the overminus than the nonoverminus group (-0.42 D vs -0.04 D; adjusted difference, -0.37 D; 95% CI, -0.49 to -0.26 D; P < .001), with 33 of 189 children (17%) in the overminus group vs 2 of 169 (1%) in the nonoverminus group having a shift higher than 1.00 D. CONCLUSIONS AND RELEVANCE: Children 3 to 10 years of age had improved distance exotropia control when assessed wearing overminus spectacles after 12 months of overminus treatment; however, this treatment was associated with increased myopic shift. The beneficial effect of overminus lens therapy on distance exotropia control was not maintained after treatment was tapered off for 3 months and children were examined 3 months later. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02807350.
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Exotropía , Miopía , Errores de Refracción , Niño , Preescolar , Enfermedad Crónica , Exotropía/terapia , Anteojos , Femenino , Humanos , MasculinoRESUMEN
Importance: Intravitreous bevacizumab (0.25 mg to 0.625 mg) is commonly used to treat type 1 retinopathy of prematurity (ROP), but there are concerns about systemic toxicity, particularly the risk of neurodevelopmental delay. A much lower dose may be effective for ROP while reducing systemic risk. Previously, after testing doses of 0.25 mg to 0.031 mg, doses as low as 0.031 mg were found to be effective in small cohorts of infants. Objective: To find the lowest dose of intravitreous bevacizumab effective for severe ROP. Design, Setting, and Participants: Between April 2017 and May 2019, 59 premature infants with type 1 ROP in 1 or both eyes were enrolled in a masked, multicenter, dose de-escalation study. In cohorts of 10 to 14 infants, 1 eye per infant received 0.016 mg, 0.008 mg, 0.004 mg, or 0.002 mg of intravitreous bevacizumab. Diluted bevacizumab was prepared by individual research pharmacies and delivered using 300-µL syringes with 5/16-inch, 30-guage fixed needles. Analysis began July 2019. Interventions: Bevacizumab intravitreous injections at 0.016 mg, 0.008 mg, 0.004 mg, or 0.002 mg. Main Outcomes and Measures: Success was defined as improvement by 4 days postinjection and no recurrence of type 1 ROP or severe neovascularization requiring additional treatment within 4 weeks. Results: Fifty-five of 59 enrolled infants had 4-week outcomes completed; the mean (SD) birth weight was 664 (258) g, and the mean (SD) gestational age was 24.8 (1.6) weeks. A successful 4-week outcome was achieved for 13 of 13 eyes (100%) receiving 0.016 mg, 9 of 9 eyes (100%) receiving 0.008 mg, 9 of 10 eyes (90%) receiving 0.004 mg, but only 17 of 23 eyes (74%) receiving 0.002 mg. Conclusions and Relevance: These data suggest that 0.004 mg may be the lowest dose of bevacizumab effective for ROP. Further investigation is warranted to confirm effectiveness of very low-dose intravitreous bevacizumab and its effect on plasma vascular endothelial growth factor levels and peripheral retinal vascularization.
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Bevacizumab/administración & dosificación , Retinopatía de la Prematuridad/tratamiento farmacológico , Inhibidores de la Angiogénesis/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Inyecciones Intravítreas , Masculino , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Retina/patología , Retinopatía de la Prematuridad/diagnóstico , Resultado del TratamientoRESUMEN
S. aureus is a significant cause of late-onset sepsis in neonates. Increasing antibiotic resistance, however, requires additional treatment options. Lysostaphin, an endopeptidase, has that potential. The objective of this study is to compare lysostaphin versus vancomycin against methicillin-resistant Staphylococcus aureus (MRSA) in a neonatal mouse model. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against MRSA strain USA300 were determined using standard methods. To determine pharmacokinetics, neonatal pups received either vancomycin or lysostaphin intraperitoneal and serum samples were obtained. To evaluate efficacy, pups were infected s.c. and littermates randomized to receive either saline, vancomycin, or lysostaphin intraperitoneal. Pups were observed for survival and growth. Quantitative blood cultures were obtained 24 h after infection. The MIC/MBC for vancomycin and lysostaphin were 0.71/1.19 microg/mL and <0.008/0.015 microg/mL, respectively. Mean lysostaphin concentrations ranged from 2.34 to 8.92 microg/mL. Mean vancomycin concentrations ranged from 1.72 to 11.2 microg/mL. Lysostaphin improved survival compared with placebo (p < 0.00001) and vancomycin (p < 0.03). There was no significant difference in growth among the groups. All treatment regimens resulted in less bacteremia compared with placebo (p < 0.0001). Lysostaphin appears to be more effective than vancomycin in treating MRSA in a neonatal model.
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Antibacterianos/farmacología , Lisostafina/farmacología , Resistencia a la Meticilina , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Vancomicina/farmacología , Animales , Animales Recién Nacidos , Antibacterianos/administración & dosificación , Antibacterianos/farmacocinética , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Recuento de Colonia Microbiana , Modelos Animales de Enfermedad , Inyecciones Intraperitoneales , Lisostafina/administración & dosificación , Lisostafina/farmacocinética , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Ratones , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/microbiología , Vancomicina/administración & dosificación , Vancomicina/farmacocinéticaRESUMEN
Ureaplasma infection is associated with increased lung disease in high-risk neonates. Our goal was to determine the impact of antibiotic prophylaxis on Ureaplasma and oxygen-induced lung disease in newborn mice. In animal model development and prophylaxis experiments, pups were randomly assigned to either 0.8 or 0.21 inspired oxygen concentration [fraction of inspired oxygen (FiO2)] from 1 to 14 d of age and either Ureaplasma or 10 B media daily from 1 to 3 d. All pups were observed for growth and survival. Surviving pups had culture and PCR evaluated for blood, bronchoalveolar lavage, and lung, and lung weights, pathology, morphometry, histology, and immunohistochemistry were determined. In prophylaxis experiments, erythromycin, azithromycin, or normal saline was given for the first 3 d, and minimum inhibitory concentration and pharmacokinetics were determined. In model development, 0.8 FiO2 and Ureaplasma infection survival and growth were significantly decreased and lung edema and inflammation were significantly increased. In prophylaxis experiments, we observed significantly improved survival and growth with azithromycin versus normal saline controls, whereas erythromycin was not significantly different from controls, and decreased inflammatory response with azithromycin versus normal saline and erythromycin. In a neonatal mouse model of Ureaplasma and oxygen-induced lung disease, appropriate antibiotic prophylaxis improves survival and morbidity and decreases lung inflammation.
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Animales Lactantes/microbiología , Profilaxis Antibiótica , Enfermedades Pulmonares , Infecciones por Ureaplasma/tratamiento farmacológico , Ureaplasma/efectos de los fármacos , Animales , Animales Recién Nacidos , Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Líquido del Lavado Bronquioalveolar/microbiología , Femenino , Humanos , Recién Nacido , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/microbiología , Ratones , Embarazo , Distribución Aleatoria , Tasa de SupervivenciaRESUMEN
PURPOSE: To evaluate long-term corneal outcomes in pediatric patients who underwent photorefractive keratotomy (PRK) for the treatment of refractive amblyopia. METHODS: In this prospective interventional case series, children with refractive amblyopia underwent PRK between January 1, 2007, and December 31, 2011, at Texas Children's Hospital's Department of Ophthalmology, a single tertiary eye center, and were followed for at least 5 years after surgery. Main outcome measures were 5+ years postoperative indices of corneal thickness, keratometry, degree of corneal haze, and presence or absence of keratectasia. RESULTS: Twelve eyes of 8 subjects aged 3-9 years who underwent PRK and were followed for at least 5 years were included. The mean PRK treatment dose was 8.46 D for the myopic cohort and 4.49 D for the hyperopic cohort, which removed an average of 72 µm of corneal stromal tissue in addition to the 50 µm of corneal epithelium that was removed prior to laser ablation. The mean corneal thickness was 563 µm preoperatively, which decreased to 441 µm immediately following the PRK. The mean corneal thickness 5+ years after PRK was stable, at 498 µm, because of epithelial regrowth. None of the subjects developed visually significant corneal haze or topographic evidence of keratectasia. CONCLUSIONS: In this study cohort, there were no topographic signs of keratectasia or corneal haze in children treated with PRK for high refractive error 5 years or more after surgery.
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Ambliopía/cirugía , Córnea/patología , Topografía de la Córnea/métodos , Queratectomía Fotorrefractiva/efectos adversos , Complicaciones Posoperatorias , Ambliopía/diagnóstico , Niño , Preescolar , Córnea/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pronóstico , Estudios Prospectivos , Refracción Ocular , Factores de TiempoRESUMEN
Lactoferrin has broad-spectrum antimicrobial activity, and the authors hypothesized that recombinant human lactoferrin (Talactoferrin alfa [TLF]) would reduce mortality and morbidity in a coinfection model. The MIC 50 (minimum inhibitory concentration required to inhibit the growth of 50% of organisms) of TLF against Candida albicans and Staphylococcus epidermidis was determined. Neonatal Wistar rats were infected with C albicans or S epidermidis or both, at doses of 2 x10(8) colony-forming units (CFUs) given subcutaneously. Rat pups in each group were randomly given TLF intraperitoneally at 40 mg/kg/dose or 300 mg/kg/dose, or saline in 0.2 mL, once a day for 4 d and were monitored for mortality, weight gain, and blood culture positivity. Trough serum levels of TLF were measured at 24, 48, 72, 96, and 144 h. MIC 50 of TLF was 30 microg/mL and 500 microg/mL for C albicans and S epidermidis, respectively. TLF prophylaxis significantly improved survival in the coinfection group at 40 mg/kg/dose (by 16.1%; P=.019) and at 300 mg/kg/dose (by 15.1%; P=.027) and in the S epidermidis group at a dose of 40 mg/kg/dose (by 18.6%; P=.04). Weight gain was not affected by TLF prophylaxis. Serum trough levels of TLF were 1000-fold lower than in vitro MIC 50. The authors conclude that lactoferrin prophylaxis significantly enhanced survival in coinfection and in the subgroup of S epidermidis infection (40 mg/kg/dose) through indirect mechanisms.
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Antiinfecciosos/uso terapéutico , Candidiasis/tratamiento farmacológico , Lactoferrina/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Animales , Animales Recién Nacidos , Antiinfecciosos/administración & dosificación , Antiinfecciosos/farmacocinética , Candida albicans/efectos de los fármacos , Candidiasis/complicaciones , Candidiasis/mortalidad , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Lactoferrina/administración & dosificación , Lactoferrina/farmacocinética , Pruebas de Sensibilidad Microbiana , Distribución Aleatoria , Ratas , Ratas Wistar , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Infecciones Estafilocócicas/complicaciones , Infecciones Estafilocócicas/mortalidad , Staphylococcus epidermidis/efectos de los fármacos , Aumento de PesoRESUMEN
PURPOSE: To report long-term outcomes of primary intraocular lens (IOL) placement in patients aged 7 to 24 months. METHODS: This was a retrospective study of 27 consecutive patients (28 eyes) aged 7 to 24 months who underwent cataract surgery with primary IOL placement. RESULTS: Average follow-up was 62.7 ± 41.7 months and the mean age of surgery was 14.4 ± 5.6 months. Mean final visual acuity was 1.02 ± 0.72 logMAR (20/209). Adverse events occurred in 7 eyes (25%) and included visual axis opacification in 6 eyes and pupillary block glaucoma in 1 eye. Seven patients (25.9%) required additional intraocular surgery. Strabismus was present in 19 patients (70.4%). Better stereopsis was correlated with better final acuity. CONCLUSIONS: Cataract surgery with IOL placement in patients aged 7 to 24 months is associated with few complications. Visual axis opacification is the most frequent adverse event. [J Pediatr Ophthalmol Strabismus. 2017;54(3):149-155.].
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Extracción de Catarata , Implantación de Lentes Intraoculares/métodos , Complicaciones Posoperatorias/epidemiología , Agudeza Visual/fisiología , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Masculino , Estudios Retrospectivos , Texas/epidemiología , Factores de Tiempo , Resultado del TratamientoRESUMEN
OBJECTIVE: To evaluate the outcomes of cataract surgery in pediatric patients presenting with bilateral infantile cataracts and nystagmus. DESIGN: Retrospective case study. PARTICIPANTS: Thirteen pediatric patients who presented between September 2002 and February 2014 at a single tertiary care institution. METHODS: Patients were included if they presented with bilateral visually significant cataracts and preoperative manifest nystagmus and had no other systemic or ocular condition that could explain the presence of the nystagmus. Data collected included best-corrected visual acuity (BCVA), etiology of cataracts, associated systemic/ocular conditions, status of strabismus, surgical complications, and presence of nystagmus. RESULTS: Mean age at diagnosis of the cataracts was 8.1 ± 10.6 months. Mean age at surgery was 8.4 ± 10.5 months. Average length of follow-up was 54.3 ± 32.6 months. Twelve patients were left aphakic bilaterally; 1 patient received primary intraocular lenses bilaterally. Ten patients were able to perform visual acuity at the most recent visit, with 5 out of 10 having BCVA ≥20/40 in the better-seeing eye. Two patients had no visible nystagmus and 3 patients had latent nystagmus only at the most recent visit. CONCLUSIONS: The presence of preoperative nystagmus does not preclude good visual outcomes in pediatric patients with cataracts.
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Extracción de Catarata/métodos , Catarata/complicaciones , Nistagmo Patológico/complicaciones , Agudeza Visual , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Nistagmo Patológico/fisiopatología , Estudios Retrospectivos , Factores de Tiempo , Resultado del TratamientoRESUMEN
Importance: Intravitreous bevacizumab (0.25 to 0.625 mg) is increasingly used to treat type 1 retinopathy of prematurity (ROP), but there remain concerns about systemic toxicity. A much lower dose may be effective while reducing systemic risk. Objective: To find a dose of intravitreous bevacizumab that was lower than previously used for severe ROP, was effective in this study, and could be tested in future larger studies. Design, Setting, and Participants: Between May 2015 and September 2016, 61 premature infants with type 1 ROP in 1 or both eyes were enrolled in a masked, multicenter, phase 1 dose de-escalation study. One eye of 10 to 14 infants received 0.25 mg of intravitreous bevacizumab. If successful, the dose was reduced for the next group of infants (to 0.125 mg, then 0.063 mg, and finally 0.031 mg). Diluted bevacizumab was delivered using 300 µL syringes with 5/16-inch, 30-gauge fixed needles. Interventions: Bevacizumab injections at 0.25 mg, 0.125 mg, 0.063 mg, and 0.031 mg. Main Outcomes and Measures: Success was defined as improvement in preinjection plus disease or zone I stage 3 ROP by 5 days after injection or sooner, and no recurrence of type 1 ROP or severe neovascularization requiring additional treatment within 4 weeks. Results: Fifty-eight of 61 enrolled infants had 4-week outcomes completed; mean birth weight was 709 g and mean gestational age was 24.9 weeks. Success was achieved in 11 of 11 eyes at 0.25 mg, 14 of 14 eyes at 0.125 mg, 21 of 24 eyes at 0.063 mg, and 9 of 9 eyes at 0.031 mg. Conclusions and Relevance: A dose of bevacizumab as low as 0.031 mg was effective in 9 of 9 eyes in this phase 1 study and warrants further investigation. Identifying a lower effective dose of bevacizumab may reduce the risk for neurodevelopmental disability or detrimental effects on other organs.