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1.
Nature ; 603(7902): 616-623, 2022 03.
Article in English | MEDLINE | ID: mdl-35296860

ABSTRACT

Fabrics, by virtue of their composition and structure, have traditionally been used as acoustic absorbers1,2. Here, inspired by the auditory system3, we introduce a fabric that operates as a sensitive audible microphone while retaining the traditional qualities of fabrics, such as machine washability and draping. The fabric medium is composed of high-Young's modulus textile yarns in the weft of a cotton warp, converting tenuous 10-7-atmosphere pressure waves at audible frequencies into lower-order mechanical vibration modes. Woven into the fabric is a thermally drawn composite piezoelectric fibre that conforms to the fabric and converts the mechanical vibrations into electrical signals. Key to the fibre sensitivity is an elastomeric cladding that concentrates the mechanical stress in a piezocomposite layer with a high piezoelectric charge coefficient of approximately 46 picocoulombs per newton, a result of the thermal drawing process. Concurrent measurements of electric output and spatial vibration patterns in response to audible acoustic excitation reveal that fabric vibrational modes with nanometre amplitude displacement are the source of the electrical output of the fibre. With the fibre subsuming less than 0.1% of the fabric by volume, a single fibre draw enables tens of square metres of fabric microphone. Three different applications exemplify the usefulness of this study: a woven shirt with dual acoustic fibres measures the precise direction of an acoustic impulse, bidirectional communications are established between two fabrics working as sound emitters and receivers, and a shirt auscultates cardiac sound signals.


Subject(s)
Textiles , Vibration , Wearable Electronic Devices , Acoustics , Dietary Fiber , Heart Auscultation
2.
Mol Cell ; 64(5): 926-939, 2016 12 01.
Article in English | MEDLINE | ID: mdl-27867009

ABSTRACT

Central to homologous recombination in eukaryotes is the RAD51 recombinase, which forms helical nucleoprotein filaments on single-stranded DNA (ssDNA) and catalyzes strand invasion with homologous duplex DNA. Various regulatory proteins assist this reaction including the RAD51 paralogs. We recently discovered that a RAD51 paralog complex from C. elegans, RFS-1/RIP-1, functions predominantly downstream of filament assembly by binding and remodeling RAD-51-ssDNA filaments to a conformation more proficient for strand exchange. Here, we demonstrate that RFS-1/RIP-1 acts by shutting down RAD-51 dissociation from ssDNA. Using stopped-flow experiments, we show that RFS-1/RIP-1 confers this dramatic stabilization by capping the 5' end of RAD-51-ssDNA filaments. Filament end capping propagates a stabilizing effect with a 5'→3' polarity approximately 40 nucleotides along individual filaments. Finally, we discover that filament capping and stabilization are dependent on nucleotide binding, but not hydrolysis by RFS-1/RIP-1. These data define the mechanism of RAD51 filament remodeling by RAD51 paralogs.


Subject(s)
Caenorhabditis elegans Proteins/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Intermediate Filaments/metabolism , Rad51 Recombinase/metabolism , Caenorhabditis elegans Proteins/genetics , Carrier Proteins/genetics , Carrier Proteins/metabolism , DNA, Single-Stranded/genetics , Intermediate Filaments/genetics , Multiprotein Complexes/metabolism , Protein Binding , Rad51 Recombinase/genetics , Recombinational DNA Repair
3.
Nature ; 550(7676): 360-365, 2017 10 19.
Article in English | MEDLINE | ID: mdl-28976962

ABSTRACT

The tumour suppressor complex BRCA1-BARD1 functions in the repair of DNA double-stranded breaks by homologous recombination. During this process, BRCA1-BARD1 facilitates the nucleolytic resection of DNA ends to generate a single-stranded template for the recruitment of another tumour suppressor complex, BRCA2-PALB2, and the recombinase RAD51. Here, by examining purified wild-type and mutant BRCA1-BARD1, we show that both BRCA1 and BARD1 bind DNA and interact with RAD51, and that BRCA1-BARD1 enhances the recombinase activity of RAD51. Mechanistically, BRCA1-BARD1 promotes the assembly of the synaptic complex, an essential intermediate in RAD51-mediated DNA joint formation. We provide evidence that BRCA1 and BARD1 are indispensable for RAD51 stimulation. Notably, BRCA1-BARD1 mutants with weakened RAD51 interactions show compromised DNA joint formation and impaired mediation of homologous recombination and DNA repair in cells. Our results identify a late role of BRCA1-BARD1 in homologous recombination, an attribute of the tumour suppressor complex that could be targeted in cancer therapy.


Subject(s)
BRCA1 Protein/metabolism , Base Pairing , Chromosome Pairing , Rad51 Recombinase/metabolism , Recombinational DNA Repair , Sequence Homology, Nucleic Acid , Tumor Suppressor Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , Amino Acid Sequence , BRCA1 Protein/genetics , BRCA2 Protein/genetics , BRCA2 Protein/metabolism , Fanconi Anemia Complementation Group N Protein/genetics , Fanconi Anemia Complementation Group N Protein/metabolism , Genes, BRCA1 , Genes, BRCA2 , Humans , Multiprotein Complexes/chemistry , Multiprotein Complexes/genetics , Multiprotein Complexes/metabolism , Mutation , Protein Binding , Rad51 Recombinase/genetics , Recombinational DNA Repair/genetics , Templates, Genetic , Tumor Suppressor Proteins/chemistry , Tumor Suppressor Proteins/genetics , Ubiquitin-Protein Ligases/chemistry , Ubiquitin-Protein Ligases/genetics
4.
J Prosthet Dent ; 127(5): 703-708, 2022 May.
Article in English | MEDLINE | ID: mdl-33441258

ABSTRACT

A digitally guided triple technique for bone reduction, implant placement, and immediate interim prostheses in complete-arch implant surgery is presented. This technique integrates bone reduction and implant placement information into a dual-function surgical template and introduces a digital approach to fabricating immediate interim implant-supported fixed dental prostheses with the same occlusal relationship as the one evaluated with diagnostic removable prostheses.


Subject(s)
Dental Implants , Immediate Dental Implant Loading , Dental Prosthesis, Implant-Supported , Immediate Dental Implant Loading/methods
5.
Phys Rev Lett ; 127(8): 084301, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-34477409

ABSTRACT

In this Letter, we theoretically propose and experimentally demonstrate a three-dimensional soundproof acoustic cage structure, hereby denoted as an acoustic metacage. The metacage is composed of six acoustic metamaterial slabs with open holes and hidden bypass space coiling tunnels connected to the holes. Band structure analysis reveals a novel physical mechanism to open a low-frequency broad partial band gap via the band folding in other directions, which can also be interpreted by an effective medium with indefinite effective mass density and negative effective modulus. Transmission loss in simulations and in the acoustic impedance tube are administered. Strikingly, we prove that the soundproofing effect of the metacage is robust against the airflow perturbation induced by a fan. Our work paves a road for low-frequency airborne soundproof structures in the presence of ventilation.

6.
J Acoust Soc Am ; 149(3): 1829, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33765814

ABSTRACT

This paper presents a method to characterize the effective properties of inertial acoustic metamaterial unit cells for underwater operation. The method is manifested by a fast and reliable parameter retrieval procedure utilizing both numerical simulations and measurements. The effectiveness of the method was proved to be self-consistent by a metamaterial unit cell composed of aluminum honeycomb panels with soft rubber spacers. Simulated results agree well with the measured responses of this metamaterial in a water-filled resonator tube. A sub-unity density ratio and an anisotropic mass density are simultaneously achieved by the metamaterial unit cell, making it useful in implementations of transformation acoustics. The metamaterial, together with the approach for its characterization, are expected to be useful for underwater acoustic devices.

7.
Genet Med ; 21(10): 2336-2344, 2019 10.
Article in English | MEDLINE | ID: mdl-30926958

ABSTRACT

PURPOSE: Variants in the ABCA4 gene are causal for a variety of retinal dystrophy phenotypes, including Stargardt disease (STGD1). However, 15% of patients who present with symptoms compatible with STGD1/ABCA4 disease do not have identifiable causal ABCA4 variants. We hypothesized that a case-control collapsing analysis in ABCA4-negative patients with compatible symptoms would provide an objective measure to identify additional disease genes. METHODS: We performed a genome-wide enrichment analysis of "qualifying variants"-ultrarare variants predicted to impact protein function-in protein-coding genes in 79 unrelated cases and 9028 unrelated controls. RESULTS: Despite modest sample size, two known retinal dystrophy genes, PRPH2 and CRX, achieved study-wide significance (p < 1.33 × 10-6) under a dominant disease model, and eight additional known retinal dystrophy genes achieved nominal significance (p < 0.05). Across these ten genes, the excess of qualifying variants explained up to 36.8% of affected individuals. Furthermore, under a recessive model, the cone-rod dystrophy gene CERKL approached study-wide significance. CONCLUSION: Our results indicate that case-control collapsing analyses can efficiently identify pathogenic variants in genes in non-ABCA4 retinal dystrophies. The genome-wide collapsing analysis framework is an objective discovery method particularly suitable in settings with overlapping disease phenotypes.


Subject(s)
Homeodomain Proteins/genetics , Peripherins/genetics , Retinal Dystrophies/genetics , Trans-Activators/genetics , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , Adult , Case-Control Studies , Female , Genes, Recessive , Genome-Wide Association Study/methods , Genotype , Homeodomain Proteins/metabolism , Humans , Male , Mutation , Pedigree , Peripherins/metabolism , Phenotype , Phosphotransferases (Alcohol Group Acceptor)/genetics , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Stargardt Disease/genetics , Stargardt Disease/physiopathology , Trans-Activators/metabolism
8.
Nature ; 493(7430): 120-4, 2013 Jan 03.
Article in English | MEDLINE | ID: mdl-23160493

ABSTRACT

In response to genotoxic stress, a transient arrest in cell-cycle progression enforced by the DNA-damage checkpoint (DDC) signalling pathway positively contributes to genome maintenance. Because hyperactivated DDC signalling can lead to a persistent and detrimental cell-cycle arrest, cells must tightly regulate the activity of the kinases involved in this pathway. Despite their importance, the mechanisms for monitoring and modulating DDC signalling are not fully understood. Here we show that the DNA-repair scaffolding proteins Slx4 and Rtt107 prevent the aberrant hyperactivation of DDC signalling by lesions that are generated during DNA replication in Saccharomyces cerevisiae. On replication stress, cells lacking Slx4 or Rtt107 show hyperactivation of the downstream DDC kinase Rad53, whereas activation of the upstream DDC kinase Mec1 remains normal. An Slx4-Rtt107 complex counteracts the checkpoint adaptor Rad9 by physically interacting with Dpb11 and phosphorylated histone H2A, two positive regulators of Rad9-dependent Rad53 activation. A decrease in DDC signalling results from hypomorphic mutations in RAD53 and H2A and rescues the hypersensitivity to replication stress of cells lacking Slx4 or Rtt107. We propose that the Slx4-Rtt107 complex modulates Rad53 activation by a competition-based mechanism that balances the engagement of Rad9 at replication-induced lesions. Our findings show that DDC signalling is monitored and modulated through the direct action of DNA-repair factors.


Subject(s)
Cell Cycle Checkpoints/physiology , Cell Cycle Proteins/metabolism , DNA Repair/physiology , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/metabolism , Binding, Competitive , Cell Cycle Proteins/antagonists & inhibitors , Cell Cycle Proteins/deficiency , Cell Cycle Proteins/genetics , Checkpoint Kinase 2 , DNA Damage/drug effects , DNA Repair/drug effects , DNA Replication/drug effects , Endodeoxyribonucleases/deficiency , Endodeoxyribonucleases/metabolism , Enzyme Activation , Histones/chemistry , Histones/genetics , Histones/metabolism , Hydroxyurea/pharmacology , Intracellular Signaling Peptides and Proteins/metabolism , Mutation , Nuclear Proteins/deficiency , Nuclear Proteins/metabolism , Phosphorylation , Protein Binding , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Signal Transduction , Stress, Physiological/drug effects
9.
Nucleic Acids Res ; 45(2): 749-761, 2017 01 25.
Article in English | MEDLINE | ID: mdl-27903895

ABSTRACT

Homologous recombination (HR) is a crucial pathway for double-stranded DNA break (DSB) repair. During the early stages of HR, the newly generated DSB ends are processed to yield long single-stranded DNA (ssDNA) overhangs, which are quickly bound by replication protein A (RPA). RPA is then replaced by the DNA recombinase Rad51, which forms extended helical filaments on the ssDNA. The resulting nucleoprotein filament, known as the presynaptic complex, is responsible for pairing the ssDNA with homologous double-stranded DNA (dsDNA), which serves as the template to guide DSB repair. Here, we use single-molecule imaging to visualize the interplay between human RPA (hRPA) and human RAD51 during presynaptic complex assembly and disassembly. We demonstrate that ssDNA-bound hRPA can undergo facilitated exchange, enabling hRPA to undergo rapid exchange between free and ssDNA-bound states only when free hRPA is present in solution. Our results also indicate that the presence of free hRPA inhibits RAD51 filament nucleation, but has a lesser impact upon filament elongation. This finding suggests that hRPA exerts important regulatory influence over RAD51 and may in turn affect the properties of the assembled RAD51 filament. These experiments provide an important basis for further investigations into the regulation of human presynaptic complex assembly.


Subject(s)
DNA, Single-Stranded/metabolism , Rad51 Recombinase/metabolism , Replication Protein A/metabolism , Adenosine Triphosphate/metabolism , Carrier Proteins , Humans , Hydrolysis , Multiprotein Complexes , Protein Binding , Protein Stability
10.
J Biol Chem ; 292(28): 11702-11713, 2017 07 14.
Article in English | MEDLINE | ID: mdl-28551686

ABSTRACT

Rad52 is a highly conserved protein involved in the repair of DNA damage. Human RAD52 has been shown to mediate single-stranded DNA (ssDNA) and is synthetic lethal with mutations in other key recombination proteins. For this study, we used single-molecule imaging and ssDNA curtains to examine the binding interactions of human RAD52 with replication protein A (RPA)-coated ssDNA, and we monitored the fate of RAD52 during assembly of the presynaptic complex. We show that RAD52 binds tightly to the RPA-ssDNA complex and imparts an inhibitory effect on RPA turnover. We also found that during presynaptic complex assembly, most of the RPA and RAD52 was displaced from the ssDNA, but some RAD52-RPA-ssDNA complexes persisted as interspersed clusters surrounded by RAD51 filaments. Once assembled, the presence of RAD51 restricted formation of new RAD52-binding events, but additional RAD52 could bind once RAD51 dissociated from the ssDNA. Together, these results provide new insights into the behavior and dynamics of human RAD52 during presynaptic complex assembly and disassembly.


Subject(s)
DNA, Single-Stranded/metabolism , Presynaptic Terminals/metabolism , Rad51 Recombinase/metabolism , Rad52 DNA Repair and Recombination Protein/metabolism , Replication Protein A/metabolism , Enzyme Stability , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Humans , Kinetics , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Microscopy, Fluorescence , Nerve Tissue Proteins/chemistry , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Presynaptic Terminals/enzymology , Protein Multimerization , Protein Stability , Rad51 Recombinase/chemistry , Rad51 Recombinase/genetics , Rad52 DNA Repair and Recombination Protein/chemistry , Rad52 DNA Repair and Recombination Protein/genetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Replication Protein A/chemistry , Replication Protein A/genetics , Red Fluorescent Protein
11.
J Acoust Soc Am ; 140(1): 95, 2016 07.
Article in English | MEDLINE | ID: mdl-27475135

ABSTRACT

Previous acoustic cloaks designed with transformation acoustics always involve inhomogeneous material. In this paper, a design of acoustic polygonal cloak is proposed using linear polygonal transformation method. The designed acoustic polygonal cloak has homogeneous and anisotropic parameters, which is much easier to realize in practice. Furthermore, a possible acoustic metamaterial structure to realize the cloak is proposed. Simulation results on the real structure show that the metamaterial acoustic cloak is effective to reduce the scattering of the object.

12.
Nat Commun ; 15(1): 8046, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39277584

ABSTRACT

Invisibility cloaks that can suppress wave scattering by objects have attracted a tremendous amount of interest in the past two decades. In comparison to prior methods that were severely limited by narrow bandwidths, here we present a practical strategy to suppress sound scattering across an ultra-broad spectrum by leveraging illusion metamaterials. Consisting of a collection of subwavelength tunnels with precisely crafted internal structures, this illusion metamaterial has the ability to guide acoustic waves around the obstacles and accurately recreate the incoming wavefront on the exit surface. Remarkably, two ultra-broadband illusionary effects are produced, disappearing space and time shift. Sound scatterings are removed at all frequencies below a limit determined by the tunnel width, as confirmed by full-wave simulations and acoustic experiments. Our strategy represents a universal approach to solve the key bottleneck of bandwidth limitation in the field of cloaking in transmission, and establishes a metamaterial platform that enables the long-desired ultra-broadband sound manipulation such as acoustic camouflage and reverberation control, opening up exciting new possibilities in practical applications.

13.
Int J Ophthalmol ; 17(5): 869-876, 2024.
Article in English | MEDLINE | ID: mdl-38766331

ABSTRACT

AIM: To investigate the difference in risk factors between non-arteritic anterior ischaemic optic neuropathy (NAION) and central retinal artery occlusion (CRAO) and develop a predictive diagnostic nomogram. METHODS: The study included 37 patients with monocular NAION, 20 with monocular CRAO, and 24 with hypertension. Gender, age, and systemic diseases were recorded. Blood routine, lipids, hemorheology, carotid and brachial artery doppler ultrasound, and echocardiography were collected. The optic disc area, cup area, and cup-to-disc ratio (C/D) of the unaffected eye in the NAION and CRAO group and the right eye in the hypertension group were measured. RESULTS: The carotid artery intimal medial thickness (C-IMT) of the affected side of the CRAO group was thicker (P=0.039) and its flow-mediated dilation (FMD) was lower (P=0.049) than the NAION group. Compared with hypertension patients, NAION patients had higher whole blood reduced viscosity low-shear (WBRV-L) and erythrocyte aggregation index (EAI; P=0.045, 0.037), and CRAO patients had higher index of rigidity of erythrocyte (IR) and erythrocyte deformation index (EDI; P=0.004, 0.001). The optic cup and the C/D of the NAION group were smaller than the other two groups (P<0.0001). The diagnostic prediction model showed high diagnostic specificity (83.7%) and sensitivity (85.6%), which was highly related to hypertension, the C-IMT of the affected side, FMD, platelet (PLT), EAI, and C/D. CONCLUSION: CRAO patients show thicker C-IMT and worse endothelial function than NAION. NAION and CRAO may be related to abnormal hemorheology. A small cup and small C/D may be involved in NAION. The diagnostic nomogram can be used to preliminarily identify NAION and CRAO.

14.
Ophthalmol Sci ; 4(6): 100564, 2024.
Article in English | MEDLINE | ID: mdl-39253554

ABSTRACT

Purpose: Electronic health records (EHRs) contain a vast amount of clinical data. Improved automated classification approaches have the potential to accurately and efficiently identify patient cohorts for research. We evaluated if a rule-based natural language processing (NLP) algorithm using clinical notes performed better for classifying proliferative diabetic retinopathy (PDR) and nonproliferative diabetic retinopathy (NPDR) severity compared with International Classification of Diseases, ninth edition (ICD-9) or 10th edition (ICD-10) codes. Design: Cross-sectional study. Subjects: Deidentified EHR data from an academic medical center identified 2366 patients aged ≥18 years, with diabetes mellitus, diabetic retinopathy (DR), and available clinical notes. Methods: From these 2366 patients, 306 random patients (100 training set, 206 test set) underwent chart review by ophthalmologists to establish the gold standard. International Classification of Diseases codes were extracted from the EHR. The notes algorithm identified positive mention of PDR and NPDR severity from clinical notes. Proliferative diabetic retinopathy and NPDR severity classification by ICD codes and the notes algorithm were compared with the gold standard. The entire DR cohort (N = 2366) was then classified as having presence (or absence) of PDR using ICD codes and the notes algorithm. Main Outcome Measures: Sensitivity, specificity, positive predictive value (PPV), negative predictive value, and F1 score for the notes algorithm compared with ICD codes using a gold standard of chart review. Results: For PDR classification of the test set patients, the notes algorithm performed better than ICD codes for all metrics. Specifically, the notes algorithm had significantly higher sensitivity (90.5% [95% confidence interval 85.7, 94.9] vs. 68.4% [60.4, 75.3]), but similar PPV (98.0% [95.4-100] vs. 94.7% [90.3, 98.3]) respectively. The F1 score was 0.941 [0.910, 0.966] for the notes algorithm compared with 0.794 [0.734, 0.842] for ICD codes. For PDR classification, ICD-10 codes performed better than ICD-9 codes (F1 score 0.836 [0.771, 0.878] vs. 0.596 [0.222, 0.692]). For NPDR severity classification, the notes algorithm performed similarly to ICD codes, but performance was limited by small sample size. Conclusions: The notes algorithm outperformed ICD codes for PDR classification. The findings demonstrate the significant potential of applying a rule-based NLP algorithm to clinical notes to increase the efficiency and accuracy of cohort selection for research. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

15.
Food Sci Nutr ; 12(2): 1095-1104, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38370070

ABSTRACT

Three-spot seahorse (Hippocampus trimaculatus) has been consumed as traditional Chinese medicine in Asian society. This study was designed to analyze the bioactive compounds of the solvent extracts from cultured three-spot seahorse by high pressure liquid chromatography coupled with electrospray ionization tandem mass spectrometry (HPLC-ESI/MS/MS). Subsequently, their biological activities were evaluated and confirmed by cell modes and Western blot analysis. Experimental results indicated that taurine and arginine were the primary bioactive compounds identified and quantified without pre- or post-column derivatization within 20 min retention time. The analytical method was established and validated with intraday/interday RSD from 0.25% to 3.34% and with recovery from 87.8% to 91.2%. As compared to other extracts, water layer extract (WLE) contained the most taurine and arginine contents of 6.807 and 0.437 mg/g (dry basis), respectively. In the meanwhile, WLE also showed anti-inflammatory activity on LPS-induced NO production and inhibited the protein expression of TNF-α and COX-2 by Western blot analysis with better cell viability.

16.
Ophthalmol Sci ; 4(3): 100458, 2024.
Article in English | MEDLINE | ID: mdl-38317868

ABSTRACT

Objective: To determine if baseline diabetic retinopathy (DR) severity mediates the relationship between health insurance status and DR progression. Design: Retrospective cohort study. Subjects: Seven hundred sixteen patients aged ≥ 18 years with a diagnosis of type 1 or 2 diabetes mellitus, and a diagnosis of nonproliferative DR (NPDR) were identified from the electronic health record of a tertiary academic center between June 2012 and February 2022. Methods: NPDR severity at baseline was the proposed mediator in the relationship between insurance status and proliferative DR (PDR) progression. Logistic regression was used to determine the association between insurance status and NPDR severity at baseline, and Cox proportional hazards regression was used to assess the association between insurance status and time to PDR progression. To analyze the mediation effect of NPDR severity at baseline, a counterfactual approach, which decomposes a total effect into a natural direct effect and a natural indirect effect was applied. Main Outcome Measures: Time to progression from first NPDR diagnosis to first PDR diagnosis. Results: Of the 716 patients, 581 (81%) had Medicare or private insurance, 107 (15%) had Medicaid, and 28 (4.0%) were uninsured at their baseline eye visit. Uninsured or Medicaid patients had a higher proportion of moderate or severe NPDR at their baseline eye visit and a higher proportion of progression to PDR. After adjusting for confounders and NPDR severity at baseline, patients who were uninsured had significantly greater risk of progression to PDR compared with that of patients with Medicare/private insurance (hazard ratio [HR]: 2.63; 95% confidence interval [CI]: 1.10-6.25). Patients with Medicaid also had an increased risk of progression to PDR compared with that of patients with Medicare/private insurance, although not statistically significant (HR: 1.53; 95% CI: 0.81-2.89). NPDR severity at baseline mediated 41% of the effect of insurance status (uninsured vs. Medicare/private insurance) on PDR progression. Conclusions: Patients who were uninsured were more likely to have an advanced stage of NPDR at their baseline eye visit and were at significantly greater risk of progression to PDR compared with patients who had Medicare or were privately insured. Mediation analysis revealed that differences in baseline NPDR severity by insurance explained a significant proportion of the relationship between insurance status and DR progression. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

17.
Adv Mater ; 36(28): e2313328, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38561634

ABSTRACT

Whether intentionally generating acoustic waves or attempting to mitigate unwanted noise, sound control is an area of challenge and opportunity. This study investigates traditional fabrics as emitters and suppressors of sound. When attached to a single strand of a piezoelectric fiber actuator, a silk fabric emits up to 70 dB of sound. Despite the complex fabric structure, vibrometer measurements reveal behavior reminiscent of a classical thin plate. Fabric pore size relative to the viscous boundary layer thickness is found-through comparative fabric analysis-to influence acoustic-emission efficiency. Sound suppression is demonstrated using two distinct mechanisms. In the first, direct acoustic interference is shown to reduce sound by up to 37 dB. The second relies on pacifying the fabric vibrations by the piezoelectric fiber, reducing the amplitude of vibration waves by 95% and attenuating the transmitted sound by up to 75%. Interestingly, this vibration-mediated suppression in principle reduces sound in an unlimited volume. It also allows the acoustic reflectivity of the fabric to be dynamically controlled, increasing by up to 68%. The sound emission and suppression efficiency of a 130 µm silk fabric presents opportunities for sound control in a variety of applications ranging from apparel to transportation to architecture.

18.
Ophthalmol Sci ; 4(3): 100440, 2024.
Article in English | MEDLINE | ID: mdl-38284098

ABSTRACT

Purpose: Metformin use has been associated with a decreased risk of age-related macular degeneration (AMD) progression in observational studies. We aimed to evaluate the efficacy of oral metformin for slowing geographic atrophy (GA) progression. Design: Parallel-group, multicenter, randomized phase II clinical trial. Participants: Participants aged ≥ 55 years without diabetes who had GA from atrophic AMD in ≥ 1 eye. Methods: We enrolled participants across 12 clinical centers and randomized participants in a 1:1 ratio to receive oral metformin (2000 mg daily) or observation for 18 months. Fundus autofluorescence imaging was obtained at baseline and every 6 months. Main Outcome Measures: The primary efficacy endpoint was the annualized enlargement rate of the square root-transformed GA area. Secondary endpoints included best-corrected visual acuity (BCVA) and low luminance visual acuity (LLVA) at each visit. Results: Of 66 enrolled participants, 34 (57 eyes) were randomized to the observation group and 32 (53 eyes) were randomized to the treatment group. The median follow-up duration was 13.9 and 12.6 months in the observation and metformin groups, respectively. The mean ± standard error annualized enlargement rate of square root transformed GA area was 0.35 ± 0.04 mm/year in the observation group and 0.42 ± 0.04 mm/year in the treatment group (risk difference = 0.07 mm/year, 95% confidence interval = -0.05 to 0.18 mm/year; P = 0.26). The mean ± standard error decline in BCVA was 4.8 ± 1.7 letters/year in the observation group and 3.4 ± 1.1 letters/year in the treatment group (P = 0.56). The mean ± standard error decline in LLVA was 7.3 ± 2.5 letters/year in the observation group and 0.8 ± 2.2 letters/year in the treatment group (P = 0.06). Fourteen participants in the metformin group experienced nonserious adverse events related to metformin, with gastrointestinal side effects as the most common. No serious adverse events were attributed to metformin. Conclusions: The results of this trial as conducted do not support oral metformin having effects on reducing the progression of GA. Additional placebo-controlled trials are needed to explore the role of metformin for AMD, especially for earlier stages of the disease. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

19.
J Pediatr Ophthalmol Strabismus ; 60(4): e38-e40, 2023.
Article in English | MEDLINE | ID: mdl-37478197

ABSTRACT

The authors report a case of lacrimo-auriculo-dento-digital syndrome in a 16-month-old boy with punctal agenesis, upper canalicular dysgenesis and polydactyly, presenting as bilateral congenital nasolacrimal duct obstruction and unilateral acute dacryocystitis. Genetic sequencing revealed a novel mutation in fibroblast growth factor 10. [J Pediatr Ophthalmol Strabismus. 2023;60(4):e38-e40.].


Subject(s)
Hearing Loss , Lacrimal Duct Obstruction , Nasolacrimal Duct , Male , Humans , Infant , Lacrimal Duct Obstruction/diagnosis , Lacrimal Duct Obstruction/therapy , Lacrimal Duct Obstruction/complications , Fibroblast Growth Factor 10
20.
Am J Ophthalmol Case Rep ; 29: 101791, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36686266

ABSTRACT

Purpose: To describe the clinical, optical coherence tomography (OCT), and histopathological findings of a patient who was found to have ossification of a pre-retinal membrane after multiple surgical repairs for retinal detachment. Methods: The patient had comprehensive ophthalmic examinations during seven years of follow-up and underwent surgical removal of her pre-retinal membrane. Results: A 24-year-old woman with a history of retinal detachment and multiple retina surgeries presented with baseline vision of 20/200 and refractory glaucoma in the left eye (right eye with no light perception due to prior failed retinal detachment repair). OCT showed a thick epiretinal membrane with hypo-reflective intraretinal spaces in the macula, and exam revealed a chronic retinal detachment superotemporally surrounded by laser barricade. She was stable for six years and then experienced vision loss and decreasing eye pressure, concurrent with rapid evolution of pre-retinal fibrosis, leading to a vascularized consolidation in the mid-periphery, for which she underwent vitrectomy and membrane peel. The vascularized lesion over the area of detachment in the superotemporal retina was removed en bloc through the anterior chamber. Pathological findings revealed woven bone formation anterior to the internal limiting membrane, and the tissue was GFAP negative. Conclusions: Our case adds to the limited knowledge of the chronology, presentation, and surgical management of intraocular ossification, especially of the rarer pre-retinal type. Our patient highlights that development of ossification can happen more quickly than previously thought (year or years rather than decades), can be hidden under vascularized lesions, and is dynamic, with simultaneous release of traction in one area and increased traction in another. Diligent follow-up is indicated even in cases of vitreous membranes from retinal detachment that otherwise appear to have been stable for years.

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