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2.
J AAPOS ; : 103937, 2024 May 18.
Article in English | MEDLINE | ID: mdl-38768773

ABSTRACT

A 14-year-old boy presented after 2 months of vision loss, redness, and pain in the right eye, initially treated as anterior uveitis with topical corticosteroids. He had a 1-year history of T-cell acute lymphoblastic leukemia, which had been in remission for 6 months. On examination, visual acuity in the right eye was light perception, with 4+ anterior chamber cells, pupillary membrane, and an intumescent cataract. Ultrasound biomicroscopy (UBM) revealed a ciliary body mass and capsular bag rupture. After consultation with his oncologist, he received 10 radiotherapy sessions. At 1 month, UBM showed resolution of the mass. After 1 year of remission, the patient underwent pars plana vitrectomy, pupillary membranectomy, and placement of a scleral-fixated intraocular lens. Thirty months after surgery, visual acuity was 20/25. Leukemic infiltration of the ciliary body is a rare manifestation of the disease that is often misdiagnosed as uveitis.

3.
Ophthalmic Epidemiol ; : 1-7, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38578693

ABSTRACT

PURPOSE: To identify sociodemographic factors associated with the visual outcomes of retinoblastoma survivors. METHODS: Retrospective cohort study using a US-based clinical data registry. All individuals < 18 years of age with a history of retinoblastoma in the Intelligent Research in Sight (IRIS®) Registry (1/1/2013-12/31/2020). The primary outcome was visual acuity below the threshold for legal blindness (20/200 or worse) in at least one eye. Multivariable logistic regression was used to evaluate the association between visual outcomes and age, sex, laterality, race, ethnicity, type of insurance, and geographic location. RESULTS: This analysis included 1545 children with a history of retinoblastoma. The median length of follow-up was 4.1 years (IQR, 2.2-5.9 years) and the median age at most recent clinical visit was 12 years (IQR, 8-16 years). Retinoblastoma was unilateral in 54% of cases. Poor vision in at least one eye was identified in 78% of all children and poor vision in both eyes in 17% of those with bilateral disease. Poor visual outcomes were associated with unilateral diagnosis (OR, 1.55; 95% CI,1.13-2.12; p = .007), Black race (OR, 2.03; 95% CI, 1.19-3.47; p = .010), Hispanic ethnicity (OR, 1.65; 95% CI, 1.16-2.37; p = .006), and non-private insurance (OR, 1.47; 95% CI, 1.02-2.10; p = .037). CONCLUSIONS: Poor visual outcomes appear to be more common among Black, Hispanic, and publicly insured children with a history of retinoblastoma, raising concerns regarding healthcare inequities. Primary care physicians should ensure that young children receive red reflex testing during routine visits and consider retinoblastoma in the differential diagnosis of abnormal eye exams.

4.
Ophthalmic Surg Lasers Imaging Retina ; 55(4): 235-239, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38319054

ABSTRACT

A 13-year-old Black male patient with a history of Kikuchi-Fujimoto disease (KFD) and sickle cell trait presented with acute painless vision loss and no light perception vision (NLP) in his left eye. The examination was indicative of occlusive retinal vasculitis with near total central retinal artery occlusion (CRAO). He was started on oral steroids with dramatic reperfusion and improvement of the retinal hemorrhages. However, his vision remained at NLP. Oral steroids were tapered, and rituximab infusion was initiated. While ocular involvement is uncommon in KFD, vision-limiting complications, such as occlusive retinal vasculitis, ophthalmic artery occlusion, and CRAO can occur. Early systemic immunosuppression is key in achieving rapid remission. [Ophthalmic Surg Lasers Imaging Retina 2024;55:235-239.].


Subject(s)
Fluorescein Angiography , Histiocytic Necrotizing Lymphadenitis , Retinal Vasculitis , Sickle Cell Trait , Humans , Male , Histiocytic Necrotizing Lymphadenitis/diagnosis , Histiocytic Necrotizing Lymphadenitis/complications , Histiocytic Necrotizing Lymphadenitis/drug therapy , Sickle Cell Trait/complications , Sickle Cell Trait/diagnosis , Retinal Vasculitis/diagnosis , Retinal Vasculitis/etiology , Adolescent , Fluorescein Angiography/methods , Visual Acuity , Retinal Artery Occlusion/diagnosis , Retinal Artery Occlusion/etiology , Fundus Oculi , Glucocorticoids/therapeutic use , Glucocorticoids/administration & dosage
5.
Am J Ophthalmol ; 261: 1-6, 2024 May.
Article in English | MEDLINE | ID: mdl-38232897

ABSTRACT

PURPOSE: To examine the relationship between the Child Opportunity Index (COI) and severity of retinoblastoma at presentation. DESIGN: Cross-sectional study. METHODS: Children (age <18 years) treated for retinoblastoma at a tertiary care center between January 2000 and May 2023 were included. Residential census tract was used to determine the overall and domain-specific COI score for each child. Collected variables included age, sex, race/ethnicity, insurance type, and the International Classification of Retinoblastoma (ICRB) Group at initial examination. The primary outcome was Group D or E retinoblastoma at presentation. Mixed effects regression models were used to estimate the association of COI scores with disease severity at presentation. RESULTS: This study included 125 children (51.2% male). Median age at diagnosis was 13 months (IQR, 5-24 months). One hundred nine (87.2%) children presented with Group D or E retinoblastoma and 33 (26.4%) resided in low or very low opportunity neighborhoods. Children residing in neighborhoods with low overall COI scores (OR, 1.62; 95% CI, 1.01-2.58; P = .044) and low education COI scores (OR, 1.77; 95% CI, 1.13-2.79; P = .013) were at increased odds of presenting with ICRB Group D or E retinoblastoma after adjusting for individual-level socioeconomic factors. CONCLUSION: Children residing in low opportunity neighborhoods-particularly low education opportunity-more often presented with advanced stage retinoblastoma than children residing in neighborhoods with higher opportunity scores. Efforts to improve preventative vision care and access to eye specialty care for children residing in low-resource areas are needed to reduce existing disparities in retinoblastoma.


Subject(s)
Retinal Neoplasms , Retinoblastoma , Child , Humans , Male , Infant , Child, Preschool , Adolescent , Female , Retinoblastoma/diagnosis , Retinoblastoma/therapy , Cross-Sectional Studies , Retrospective Studies , Socioeconomic Factors , Retinal Neoplasms/diagnosis , Retinal Neoplasms/therapy
6.
Ophthalmol Retina ; 8(2): 184-194, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37696394

ABSTRACT

PURPOSE: To longitudinally assess macular thickness and microvascular changes in children with sickle cell disease (SCD). DESIGN: A retrospective consecutive series. SUBJECTS: Children with SCD aged ≤ 18 years who had an ophthalmic examination at Boston Children's Hospital between January 1998 and August 2022. METHODS: Qualitative and quantitative analyses of both OCT and OCT angiography (OCTA) images were performed. MAIN OUTCOME MEASURES: Total retinal thickness measured on macular OCT, superficial capillary plexus and deep capillary plexus (DCP) vessel density (VD), and foveal avascular zone (FAZ) area measured on 6- × 6-mm OCTA scans. RESULTS: International Classification of Diseases, 10th Revision, code search identified 303 pediatric SCD patients who underwent ophthalmic examination during the study period. OCT and OCTA images were acquired on 104 (17.2%) and 60 (9.9%) eyes at presentation and on 159 (26.2%) and 100 (16.5%) eyes at final visit, respectively. Overall, temporal retinal thinning was noted qualitatively in 35.6% of SCD patients at presentation and 39.6% at final visit. Of those patients with macular thinning, 94.6% and 90.5% had peripheral sickle cell retinopathy (SCR) at presentation and final visit. On quantitative OCT analysis, HbSS eyes had a lower retinal thickness in the fovea and temporal parafovea compared with HbSC (P < 0.05). Eyes with peripheral SCR had a larger FAZ at presentation compared with eyes without peripheral SCR (P = 0.004), a lower DCP VD at final visit in the inferior temporal macula (P = 0.03), and a higher DCP VD at final visit in the superior nasal macula (P = 0.01). Eighty eyes of 40 patients had OCT, and 34 eyes of 20 patients had both OCT and OCTA images acquired at both initial and final visits. At final visit, retinal thickness decreased at the fovea, inferior perifovea, and temporal perifovea compared with presentation (P < 0.05). In parallel, VD DCP in the superonasal quadrant increased at final visit (P = 0.03). CONCLUSIONS: Macular retinal thinning was progressive and observed in eyes with and without peripheral SCR. Over time, there was a compensatory increase in DCP VD in the nasal macula on OCTA. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Subject(s)
Anemia, Sickle Cell , Retinal Degeneration , Humans , Child , Fluorescein Angiography/methods , Retinal Vessels , Retrospective Studies , Visual Acuity , Tomography, Optical Coherence/methods , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/diagnosis
7.
bioRxiv ; 2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37904964

ABSTRACT

BRASSINAZONE RESISTANT 1 (BZR1) is a key transcription factor of the brassinosteroid signaling pathway but also a signaling hub that integrates diverse signals that modulate plant growth. Previous studies have shown that starvation causes BZR1 degradation, but the underlying mechanisms are not understood. Here we performed quantitative proteomic analysis of BZR1 interactome under starvation conditions and identified two BZR1-interacting ubiquitin ligases, BAF1 and UPL3. Compared to the wild type, the upl3 mutants show long hypocotyl and increased BZR1 levels when grown under sugar starvation conditions but not when grown on sugar-containing media, indicating a role of UPL3 in BZR1 degradation specifically under starvation conditions. The upl3 mutants showed a reduced survival rate after starvation treatment, supporting the importance of UPL3-mediated BZR1 degradation and growth arrest for starvation survival. Treatments with inhibitors of TARGET of RAPAMYCIN (TOR) and autophagy altered BZR1 level in the wild type but were less effective in upl3 , suggesting that UPL3 mediates the TOR-regulated and autophagy-dependent degradation of BZR1. Further, the UPL3 protein level is increased posttranscriptionally by starvation but decreased by sugar treatment. Our study identifies UPL3 as a key component that mediates sugar regulation of hormone signaling pathways, important for optimal growth and survival in plants. IN A NUTSHELL: Background: The coordination between signaling pathways that monitor the levels of photosynthate and growth hormones is crucial for optimizing growth and survival, but the underlying mechanisms are not fully understood. When the sugar level is low, the BZR1 transcription factor of the brassinosteroid (BR) signaling pathway is degraded, and hence growth is attenuated to prevent starvation and enhance survival. When sugar is sufficient, sugar signaling inhibits BZR1 degradation and enables BR promotion of plant growth. The key component that mediates starvation-induced BZR1 degradation remains unknown.Question: What proteins interact with BZR1 and mediate its degradation under sugar starvation?Finding: We performed immunoprecipitation mass spectrometry analysis of BZR1 in starvation-treated Arabidopsis and identified many BZR1-interacting proteins, including two E3 ligases UPL3 and BAF1. Genetic analysis showed that UPL3 plays a specific and prominent role in promoting autophagy-dependent BZR1 degradation and plant survival under sugar-starvation conditions.Next step: How sugar-TOR signaling regulates UPL3 level remains to be studied in the future.

9.
Ophthalmic Genet ; 44(6): 591-594, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36728747

ABSTRACT

BACKGROUND: Aicardi syndrome is a neurodevelopmental disorder characterized by a triad of partial or complete agenesis of the corpus callosum, infantile spasms, and pathognomonic chorioretinal lacunae. METHODS: Examination, multimodal imaging, and genetic testing were used to guide diagnosis. RESULTS: We report a case of a pediatric patient who was initially diagnosed with refractory infantile spasms. The patient was unresponsive to conventional antiepileptic therapy, and genetic testing with whole exome and mitochondrial genome sequencing could not identify the underlying cause, so vigabatrin was initiated. The ophthalmic examination under anesthesia for vigabatrin toxicity screening revealed chorioretinal atrophy in the retinal periphery of both eyes, with two 3-disc diameter chorioretinal lacunae superotemporal and inferonasal to the optic nerve in the left eye. Given the neuroimaging findings of corpus callosum hypoplasia with polymicrogyria and ocular findings, the patient was diagnosed with Aicardi syndrome. Genetic testing revealed a novel duplication event at the Xp22 locus. CONCLUSIONS: Aicardi syndrome, albeit a rare condition, should always be considered in the differential diagnosis when investigating a female child with refractory seizures in early childhood. Genetic testing may help further our understanding of AIS and the search for a genetic etiology.


Subject(s)
Aicardi Syndrome , Spasms, Infantile , Child, Preschool , Female , Humans , Child , Aicardi Syndrome/diagnosis , Aicardi Syndrome/genetics , Spasms, Infantile/diagnosis , Spasms, Infantile/genetics , Vigabatrin , Retina , Anticonvulsants , Short Stature Homeobox Protein
10.
J AAPOS ; 27(1): 52-55, 2023 02.
Article in English | MEDLINE | ID: mdl-36521818

ABSTRACT

Immune recovery uveitis (IRU) is an ocular form of immune reconstitution inflammatory syndrome, which is rare in the pediatric population. We report a case of IRU in an 11-year-old girl with a history of cytomegalovirus (CMV) retinitis in the setting of acute leukemia, who developed uveitis, vitritis, retinitis, and vasculitis during immune reconstitution. She was found to have negative CMV antigenemia, and the disease occurred during concurrent systemic antiviral therapy. Anterior chamber tap confirmed the absence of the CMV in the eye, and recurrent blood samples continued to reveal absent CMV viral particles systemically while her lymphocyte count was steadily increasing. The patient responded to oral steroids, leading to resolution of active retinitis. Tapering the steroids caused a mild reactivation of the ocular immune response.


Subject(s)
Cytomegalovirus Retinitis , Leukemia , Uveitis , Female , Humans , Child , Cytomegalovirus Retinitis/drug therapy , CD4 Lymphocyte Count , Uveitis/drug therapy , Antiviral Agents/therapeutic use , Vitreous Body , Leukemia/complications , Leukemia/drug therapy
11.
Ophthalmol Sci ; 2(4): 100202, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36531591

ABSTRACT

Purpose: The intravitreal injection volume is known to vary with plunger alignment and the speed of injection. We investigated the role that syringe stopper deformation plays in allowing excess volumes to be injected into the eye and the potential for the vitreous humor to become incarcerated when excess force is released within the eye. Design: Experimental study. Methods: Aflibercept prefilled syringes (PFSs), ranibizumab PFSs, and 1-ml tuberculin (TB) syringes were subjected to increasing injection force to assess the extent to which each design allowed for excess volumes to be expelled after the stopper reached the bottom of the syringe barrel (i.e., after the 50-µl dose was expelled). Main Outcome Measures: Additional volume expelled with stopper deformation. Results: Syringe stoppers are capable of deformation into the dead space when additional force is applied. This allows for progressively greater medication doses to be administered. At an additional force of 3.92 N after the syringe stopper came in contact with the bottom of the syringe barrel, the aflibercept PFSs, ranibizumab PFSs, and 1-ml TB syringes dispensed an additional 17.2%, 11.4%, and 0.8% higher volume than the intended volume of 50 µl, respectively. Upon release of this force, a proportional volume was observed to be drawn back into the needle. Conclusions: The intravitreal injection volume varies with the force applied to fully depressed syringes because of syringe stopper deformation. We advise that performing forceful intravitreal injections be avoided to prevent excessive dosing of medication. We also caution that pressure applied to the plunger during intravitreal injections not be released while the needle is in the vitreous cavity to guard against vitreous incarceration, which could lead to retinal tear formation or detachment.

12.
J Pediatr Ophthalmol Strabismus ; 59(4): e39-e41, 2022.
Article in English | MEDLINE | ID: mdl-35856427

ABSTRACT

A 13-year-old boy with fragile X syndrome presented with painless, decreased vision in his right eye. Funduscopy revealed fibrotic tissue and an epiretinal membrane. This patient with fragile X syndrome was diagnosed as having combined hamartoma of the retina and retinal pigment epithelium and treated with vitrectomy and epiretinal membrane peeling. [J Pediatr Ophthalmol Strabismus. 2022;59(4):e39-e41.].


Subject(s)
Epiretinal Membrane , Fragile X Syndrome , Hamartoma , Retinal Diseases , Adolescent , Epiretinal Membrane/diagnosis , Epiretinal Membrane/surgery , Fluorescein Angiography , Fragile X Syndrome/complications , Fragile X Syndrome/diagnosis , Hamartoma/complications , Hamartoma/diagnosis , Hamartoma/surgery , Humans , Male , Retina/surgery , Retinal Diseases/complications , Retinal Diseases/diagnosis , Retinal Pigment Epithelium , Visual Acuity
13.
Proc (Bayl Univ Med Cent) ; 35(4): 562-564, 2022.
Article in English | MEDLINE | ID: mdl-35754583

ABSTRACT

Best vitelliform macular dystrophy (BVMD) is a slowly progressive macular disease caused by a pathogenic variant of the Bestrophin (BEST1) gene. Examination coupled with multimodal imaging and genetic testing are used to guide diagnosis and treatment. A 12-year-old girl was examined for decreased vision in the left eye and showed bilateral "egg-yolk"-like macular lesions with choroidal neovascularization (CNV) in the left eye. Six months later, she experienced decreased vision with appearance of CNV on optical coherence tomography angiography in the right eye. Injections of anti-vascular endothelial growth factor helped restore vision from 20/125 to 20/20 in the right eye with stabilization of her left eye (vision 20/40). Genetic testing revealed c.851A > G (p.Tyr284Cys), a heterozygous variant of the BEST1 gene. The same variant was found in her father, who was initially misdiagnosed with toxoplasmosis due to a peripheral retinal lesion in the left eye. This is the first report of bilateral consecutive CNV secondary to BVMD. Additionally, it highlights the likely pathogenic role of a novel variant of the BEST1 gene.

16.
Ophthalmol Retina ; 6(5): 411-420, 2022 05.
Article in English | MEDLINE | ID: mdl-35007768

ABSTRACT

PURPOSE: To describe the clinical course and outcomes of aggressive retinal astrocytic hamartoma (RAH) treated with oral mechanistic target of rapamycin inhibitors (mTORis). DESIGN: A retrospective clinical case series. PARTICIPANTS: Five patients with genetically confirmed tuberous sclerosis complex and visually significant RAH due to tumor growth or exudation. METHODS: In this retrospective clinical case series, a review of electronic medical records was performed to determine baseline and follow-up ophthalmic examination characteristics, along with ancillary imaging findings, in patients receiving off-label treatment with either oral sirolimus or everolimus for symptomatic RAH. MAIN OUTCOME MEASURES: Visual acuity, change in tumor size, degree of exudation, and adverse effects of the mTORis were evaluated. RESULTS: The 5 patients in this series ranged in age from 8 months to 54 years. Four were treated with sirolimus, and 1 received everolimus. In all the cases, the tumor height was stable or decreased after the treatment (median follow-up duration, 39 months; range, 11-73 months). Exudation improved after the treatment in all the cases. In an 8-month-old infant, frequent upper respiratory tract infections prompted the cessation of treatment. In 1 patient, the mTORi was temporarily withheld because of elevated liver enzyme levels. No other significant adverse effects were noted. CONCLUSIONS: Sirolimus and everolimus should be considered in the management of vision-threatening RAH, particularly in the setting of exudative and rapidly growing tumors. Four of the 5 patients in this series tolerated the oral mTORi and continued with the therapy. There were no serious complications.


Subject(s)
Hamartoma , Retinal Diseases , Everolimus/therapeutic use , Hamartoma/diagnosis , Hamartoma/drug therapy , Humans , Infant , Retinal Diseases/chemically induced , Retrospective Studies , Sirolimus/therapeutic use
17.
Eur J Ophthalmol ; 32(6): NP6-NP9, 2022 Nov.
Article in English | MEDLINE | ID: mdl-34151585

ABSTRACT

PURPOSE: To report a case of 16-month-old boy with a novel variant TSPAN12 gene-presenting as unilateral myopia, pediatric cataract, and heterochromia in a patient with familial exudative vitreoretinopathy. OBSERVATION: A 16-month-old otherwise healthy boy was referred to Boston Children's Hospital for evaluation of strabismus. Ocular examination revealed intermittent esotropia, left hypotropia, and limited left eye elevation in both adduction and abduction. Full cycloplegic hyperopic correction of +3.50 diopters (D) over both eyes was given to the patient. Over several months, refraction of the right eye showed progressive myopia (-6.00 D) with new onset iris heterochromia. Fundus examination showed there was a large area of chorioretinal atrophy with abrupt ending of the blood vessels; anterior to the ora serrata there were diffuse vitreous bands and veils that reached the lens anteriorly in direct contact with the lenticular opacity. A novel heterozygous nonsense likely pathogenic variant was identified in the TSPAN12 gene (NM_012338.3) c.315T>A (p.Cys105Ter) confirming the diagnosis of FEVR. CONCLUSION AND IMPORTANCE: Asymmetric FEVR rarely present with unilateral axial myopia however association with acquired heterochromia and cataract has never been reported. We report a case of FEVR caused by a novel TSPAN12 likely pathogenic nonsense variant presenting as unilateral progressive myopia, acquired heterochromia, and pediatric cataract.


Subject(s)
Cataract , Eye Diseases, Hereditary , Myopia, Degenerative , Retinal Diseases , Cataract/diagnosis , Cataract/genetics , Child , DNA Mutational Analysis , Familial Exudative Vitreoretinopathies , Humans , Infant , Male , Mutation , Mydriatics , Pedigree , Retina , Retinal Diseases/diagnosis , Tetraspanins/genetics
18.
J AAPOS ; 25(2): 91.e1-91.e5, 2021 04.
Article in English | MEDLINE | ID: mdl-33882352

ABSTRACT

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has significantly disrupted the delivery of healthcare. Although most nonurgent ophthalmology visits at Boston Children's Hospital were canceled, premature infants at risk for retinopathy of prematurity (ROP) still required timely, in-person care during the initial 3-month period of the infection surge in Massachusetts. The purpose of the current study was to report our protocols for mitigating risk of exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between infants and eye care providers and to compare examination rates and results with the same 3-month period in 2019. METHODS: During the infection surge, we added new infection control measures and strengthened existing ones. Additional personal protective equipment was used, and the number of ophthalmologists rotating in the three high-capacity NICUs we service was limited. RESULTS: More infants required ROP examinations during the study period in 2020 than in the same period in 2019, but fewer examinations were performed. There were no cases of missed progression to severe ROP during this time and no known transmission of SARS-CoV-2 between ROP patients and ophthalmology staff. CONCLUSIONS: Overall, effective ROP care was safely provided during the COVID-19 pandemic, and contact with this vulnerable population was minimized.


Subject(s)
COVID-19 , Retinopathy of Prematurity , Humans , Infant , Infant, Newborn , Massachusetts , Pandemics , Retinopathy of Prematurity/epidemiology , Risk Factors
19.
Plant Cell ; 32(7): 2424-2443, 2020 07.
Article in English | MEDLINE | ID: mdl-32371545

ABSTRACT

How the membrane trafficking system spatially organizes intracellular activities and intercellular signaling networks in plants is not well understood. Transport Protein Particle (TRAPP) complexes play key roles in the selective delivery of membrane vesicles to various subcellular compartments in yeast and animals but remain to be fully characterized in plants. Here, we investigated TRAPP complexes in Arabidopsis (Arabidopsis thaliana) using immunoprecipitation followed by quantitative mass spectrometry analysis of AtTRS33, a conserved core component of all TRAPP complexes. We identified 14 AtTRS33-interacting proteins, including homologs of all 13 TRAPP components in mammals and a protein that has homologs only in multicellular photosynthetic organisms and is thus named TRAPP-Interacting Plant Protein (TRIPP). TRIPP specifically associates with the TRAPPII complex through binary interactions with two TRAPPII-specific subunits. TRIPP colocalized with a subset of TRS33 compartments and trans-Golgi network markers in a TRS33-dependent manner. Loss-of-function tripp mutants exhibited dwarfism, sterility, partial photomorphogenesis in the dark, reduced polarity of the auxin transporter PIN2, incomplete cross wall formation, and altered localization of a TRAPPII-specific component. Therefore, TRIPP is a plant-specific component of the TRAPPII complex with important functions in trafficking, plant growth, and development.


Subject(s)
Arabidopsis/growth & development , Arabidopsis/metabolism , Cell Membrane/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Chlorophyta/genetics , Darkness , Mass Spectrometry/methods , Multiprotein Complexes/genetics , Multiprotein Complexes/metabolism , Mutation , Plants, Genetically Modified , Protein Interaction Maps , Vesicular Transport Proteins/genetics , Vesicular Transport Proteins/metabolism , trans-Golgi Network/metabolism
20.
J Opt Soc Am A Opt Image Sci Vis ; 33(8): 1604-11, 2016 Aug 01.
Article in English | MEDLINE | ID: mdl-27505659

ABSTRACT

Reliable and accurate testing methods are essential to guiding the polishing process during the figuring of optical telescope mirrors. With the natural advancement of technology, the procedures and instruments used to carry out this delicate task have consistently increased in sensitivity, but also in complexity and cost. Fortunately, throughout history, the Foucault knife-edge test has shown the potential to measure transverse aberrations in the order of the wavelength, mainly when described in terms of physical theory, which allows a quantitative interpretation of its characteristic shadowmaps. Our previous publication on this topic derived a closed mathematical formulation that directly relates the knife-edge position with the observed irradiance pattern. The present work addresses the quite unexplored problem of the wavefront's gradient estimation from experimental captures of the test, which is achieved by means of an optimization algorithm featuring a proposed ad hoc cost function. The partial derivatives thereby calculated are then integrated by means of a Fourier-based algorithm to retrieve the mirror's actual surface profile. To date and to the best of our knowledge, this is the very first time that a complete mathematical-grounded treatment of this optical phenomenon is presented, complemented by an image-processing algorithm which allows a quantitative calculation of the corresponding slope at any given point of the mirror's surface, so that it becomes possible to accurately estimate the aberrations present in the analyzed concave device just through its associated foucaultgrams.

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