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PURPOSE: To summarize the outcomes of corneal sight rehabilitating surgery in Stevens-Johnson syndrome (SJS). METHODS: This is a retrospective analysis of a consecutive case series. Twenty-four eyes of 18 SJS patients were included in this study. The ocular parameters, surgical procedures, postoperative complications, and additional treatments of the cases were reviewed. RESULTS: A total of 29 corneal sight rehabilitating surgeries, which consists of 9 keratoplasties, 8 Keratolimbal allograft (KLAL) and 12 combined surgeries (keratoplasty and KLAL simultaneously) were performed on the 24 eyes. All patients were treated with glucocorticoid eyedrops and tacrolimus eyedrops for anti-rejection treatment without combining systemic immunosuppression, except two patients who were prescribed prednisone tablets for the management of systemic conditions. The mean follow-up period was 50.6 ± 28.1 months. The optimal visual acuity (VA) (0.74 ± 0.60 logarithm of the minimum angle of resolution [logMAR]) and endpoint VA (1.06 ± 0.82 logMAR) were both significantly better than the preoperative VA (1.96 ± 0.43 logMAR) (95% CI, p = 0.000). 57.1% patients (8/14) were no longer in the low vision spectrum, and 88.9% patients (8/9) were no longer blind. The mean epithelialization time was 7.1 ± 7.6 weeks. The success rate was 86.7%. Additional treatments for improving epithelialization included administration of serum eyedrops (n = 10), contact lens (n = 15), amniotic membrane transplantation (n = 6), and tarsorrhaphy (n = 8). Complications included delayed epithelialization (n = 4, over 12 weeks), glaucoma (n = 11), and severe allograft opacity (n = 4). Only one graft rejection was observed. CONCLUSIONS: Keratoplasty and KLAL can remarkably enhance VA and improve low vision or even eliminate blindness for ocular complications of SJS. The outcome of the surgeries was correlated with the preoperative ocular situation and choice of operative methods.
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Doenças da Córnea , Síndrome de Stevens-Johnson , Acuidade Visual , Humanos , Síndrome de Stevens-Johnson/cirurgia , Síndrome de Stevens-Johnson/fisiopatologia , Estudos Retrospectivos , Feminino , Masculino , Adulto , Acuidade Visual/fisiologia , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Doenças da Córnea/cirurgia , Doenças da Córnea/fisiopatologia , Resultado do Tratamento , Criança , Transplante de Córnea/métodos , Seguimentos , Ceratoplastia Penetrante/métodos , Complicações Pós-Operatórias , Limbo da Córnea/cirurgiaRESUMO
PURPOSE: Allogenic transplantation of retinal pigmented epithelium monolayer sheet has experienced bottlenecks due to imperfect surgical techniques. In this study, we developed a novel approach for allogenic transplantation of big sheets of retinal pigment epithelium (RPE)-Bruch membrane complex. METHODS: RPE-Bruch membrane complex sheets of 5 × 6 mm2 to 10 × 10 mm2 were taken from donated eyes. Through a novel approach, the sheets of RPE-Bruch membrane complex were transplanted into the subretinal space of eight eyes (8 patients) with late-stage retinitis pigmentosa. The patients were followed up for 5 ± 2 months. RESULTS: All RPE-Bruch membrane complexes were successfully inserted into the subretinal space during the surgery. Follow-up examinations also showed that the grafts attached well to the transplantation site. No rejection or retinal detachment was found. CONCLUSION: Through our technique, big sheets of allogenic RPE-Bruch membrane complexes could be implanted into the subretinal space smoothly. This novel approach may be useful for big sheet of allogenic RPE-derived or stem cells-derived RPE transplantation in the treatment of RP and other retinal dystrophic diseases.
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Descolamento Retiniano , Doenças Retinianas , Retinose Pigmentar , Humanos , Epitélio Pigmentado da Retina , Lâmina Basilar da Corioide , Descolamento Retiniano/cirurgia , Retinose Pigmentar/cirurgiaRESUMO
PURPOSE: We detected the DNA of herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), varicella-zoster virus (VZV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) in donor corneas and assessed the clinical outcomes of recipients who received virus-positive grafts. METHOD: All donor corneas were analyzed for the presence of HSV-1, HSV-2, VZV, CMV, and EBV by real-time PCR from April 2017 to July 2019. The medical records of the transplant patients who received virus-positive grafts were reviewed. RESULT: Twenty-three (2.44%) donor cornea buttons tested positive for herpesviridae DNA. The positivity rates of HSV-1, CMV, VZV, and EBV were 0.74%, 0.85%, 0.64%, and 0.21%, respectively. CONCLUSION: We suggest that the corneas from donors who had cancer, donors who were inpatients, and donors who had immunodeficiency or who were on immunosuppressive therapy should be tested for herpesviridae DNA before transplantation. Finally, HSV-1 can be transmitted from graft to recipient, but that CMV cannot be transmitted according to our observations. The donor corneas found to be HSV-1-positive have to be discarded and not used for keratoplasty.
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Transplante de Córnea , Infecções por Vírus Epstein-Barr , Córnea , DNA Viral , Herpesvirus Humano 3/genética , Herpesvirus Humano 4/genética , Humanos , IncidênciaRESUMO
IMPORTANCE: There is limited literature on paediatric donors in endothelial keratoplasty. BACKGROUND: This study investigated the efficacy of and appropriate paediatric donor age for Descemet's stripping endothelial keratoplasty (DSEK). DESIGN: Retrospective and observational case series. PARTICIPANTS: Thirty-eight consecutive patients underwent DSEK with paediatric donor corneas. METHODS: The age of the donors ranged from 32 weeks gestation (premature neonate) to 3 years old. All donor consents were obtained from the parents. The causes of donor death included traffic accident, congenital heart disease and neonatal respiratory distress syndrome. MAIN OUTCOME MEASURES: The outcome measures included best-corrected visual acuity, endothelial cell loss and complications. RESULTS: Best-corrected visual acuity at last follow-up was >20/40 in 28 of 38 eyes (73.7%). The mean preoperative endothelial cell density of donor corneas was 4682 ± 520 cells/mm2 . The mean endothelial cell density of grafts was 3977 ± 556 cells/mm2 at 18 months postoperatively. Three lenticules from premature neonate donors exhibited severe contraction postoperatively. The edge of six lenticules from donors <1-year-old exhibited contraction in the early postoperative period and gradually flattened spontaneously. Graft detachment occurred in one patient. CONCLUSIONS AND RELEVANCE: DSEK with paediatric donor corneas can achieve good clinical outcomes. The corneal lenticules from 1- to 3-year- old donors are suitable for DSEK while those from donors <1-year-old are less suitable due to the possibility of severe postoperative graft contraction.
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Córnea/cirurgia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Distrofia Endotelial de Fuchs/cirurgia , Refração Ocular/fisiologia , Acuidade Visual , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Córnea/patologia , Feminino , Seguimentos , Distrofia Endotelial de Fuchs/patologia , Distrofia Endotelial de Fuchs/fisiopatologia , Sobrevivência de Enxerto , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Doadores de Tecidos , Adulto JovemRESUMO
OBJECTIVE: To summarize intra and post operation complications and their treatment of Descemet's Stripping Automated Endothelium Keratoplasty (DSAEK), and provide our experience for its development in China. METHODS: Retrospective case study. Forty-seven eyes of 42 patients underwent DSAEK performed by one surgeon. Indications include: Pseudophakic or aphakic Bullous Keratopathy, 27 eyes (57.4%); Fuchs Endothelial Dystrophy, 7 eyes (14.9%); endothelial decompensation post vitrectomy, 3 eyes (6.4%); iridocorneal endothelial syndrome (ICE), 3 eyes (6.4%); congenital glaucoma, 3 eyes (6.4%); graft failure post endothelial keratoplasty, 3 eyes (6.4%); endothelial decompensation after open ocular injury and intraocular foreign body, 1 eye (2.1%). Nineteen eyes underwent single DSAEK (40.4%); eight combined phacoemulsification and intraocular lens implantation (17.0%); eight combined anterior chamber IOL (AC-IOL) removal plus anterior segment vitrectomy and posterior chamber IOL (PC-IOL) implantation (17.0%); eight combined anterior segment vitrectomy and PC-IOL suspension (17.0%); two combined cataract extraction and anterior segment vitrectomy (4.3%); two failed in DSAEK and underwent penetrating keratoplasty (4.3%). RESULTS: Dislocation is the most common postoperative complications. Ten eyes underwent dislocation in 47 eyes (21.3%), which was solved by air and viscoelastic agent injection. High intraocular pressure happened in 12 eyes (25.5%), in 11 of which had a history of glaucoma and 1 with ICE. After drug treatment, ten patients had stable intraocular pressure and two patients underwent ciliary body photocoagulation surgery (1 case with anterior chamber intraocular lens, 1 case with ICE). Reactions happened in 2 cases (4.3%) patients, including 1 case with anterior chamber IOL (AC-IOL) rehabilitating after drug treatment and the other with Fuch's corneal endothelial dysfunction being regrafted. CONCLUSION: Dislocation is the most common complication after corneal endothelial keratoplasty, and air injection in anterior chamber is a common and effective method; High intraocular pressure is the second postoperative complication. Preoperative history of glaucoma is closely related to postoperative high intraocular pressure.
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Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Extração de Catarata , China , Doenças da Córnea/cirurgia , Endotélio , Distrofia Endotelial de Fuchs/cirurgia , Glaucoma/complicações , Humanos , Ceratoplastia Penetrante , Implante de Lente Intraocular , Hipertensão Ocular/etiologia , Facoemulsificação , Estudos Retrospectivos , Acuidade VisualRESUMO
This study reports the successful synthesis of flame-retardant and smoke-suppressing epoxy resin (EP) via bio-based polyelectrolyte flame retardants. Herein, a novel polyelectrolyte flame retardant was prepared from chitosan (CS) and hexa-(4-carboxyl-phenoxy)-cyclotriphosphazene (HCPCP) by acid-base neutralization reaction, which the HCPCP was synthesized with hexachlorocyclotriphosphazene (HCCP) and methyl p-hydroxybenzoate (MP) by nucleophilic substitution reaction. The combined effect of the addition on the flame retardant, smoke suppression and mechanical properties of EP samples were systematically investigated. The presence of this bio-based polyelectrolyte provided excellent smoke suppression and flame-retardant properties of the prepared EP. Among them, the peak heat release rate (PHRR), peak smoke production rate (PSPR) and total smoke production (TSP) of EP/9wt%3CS-HCPCP composite (the ratio of CS to HCPCP was 3: 7, and the dosage was 9 wt%) were reduced by 45.42 %, 41.66 % and 22.56 %, respectively. In addition, the EP/CS-HCPCP composites showed a 207.80 % enhancement in char residue compared to pure EP. These results suggest a green and cost-effective strategy for the production of flame-retardant, drip-proof and smoke-suppressed EP composites.
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The traditional method of preparing graphene will cause serious environmental pollution, and the combustion of polymer materials will seriously harm people's health. In this paper, a Cu-MOF-coated graphene composite flame retardant (G@Cu-MOF) rich in flame retardant elements such as B and N was synthesized through green mechanical ball milling method. Flame retardants reduce the threat to the environment and people's lives and property. After adding 6 wt% G@Cu-MOF, the peak heat release rate, total heat release rate, CO production and CO2 production of epoxy resin (EP) composite samples decreased by 55, 14, 59, and 55%, respectively. This type of Cu-MOF releases incombustible gases such as boron trifluoride (BF3) and ammonia (NH3) during combustion, diluting the concentration of combustible gases and producing copper borate in the condensed phase. Cu2+ is reduced to Cu, and boron compounds are converted into boron oxides. The thermal conductivity of graphene can reduce the temperature of the matrix, and has good flame retardancy. It synergistically acts with Cu-MOF to promote the formation of high-quality residual char, and can significantly inhibit the heat and smoke release of EP. It plays a role in flame retardancy and protecting the substrate from fire. This study provides a new approach for preparing graphene hybrid flame retardants through mechanical ball milling, in order to improve the flame retardancy of EP and suppress the release of smoke and toxic gases.
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Retardadores de Chama , Grafite , Humanos , Fumaça , Cobre , GasesRESUMO
To give silk fabric multiple functions and improve its application range, a facile and eco-friendly one-pot technique was used to endow silk fabric with dyeing, flame retardant and ultraviolet (UV)-resistant performance based on a safflower yellow derivative. The structure, surface morphology, elemental composition, thermal properties and combustion behavior of the silk samples before and after modification were all characterized. In addition, the color depth and color fastness of the dyed silk (D-silk) and flame retardant silk (FR-silk) were evaluated and measured. The positive b* value in the CIELAB color space defined the yellow color of the dyed silk fabric. The char residue increased from 2.9 wt% of the original sample to 17.4 wt% of the FR-silk at 800 °C in air atmosphere. The limiting oxygen index (LOI) of FR-silk increased from 23.3% of the control sample to 32.8% with an increase of 40.7%. The peak of heat release rate (pHRR) and total heat release (THR) of FR-silk were much lower than that of the original sample. Furthermore, the UV protection factor (UPF) of FR-silk was 73.79, indicating excellent UV-resistance properties. The preparation process was green and environment-friendly, and the FR-silk had a good application prospect.
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Microplastics (MPs) pollution evolves into a global environmental problem to be solved urgently. Although many studies are exploring ways to remove MPs from water environment, most of them are lack of selectivity and low efficiency. Herein, considering the fascinating absorption selectivity of superwetting materials, a robust magnetic-responsive superhydrophobic and superoleophilic sponge was firstly used to quickly eliminate MPs from water with very high efficiency. The functional sponge was fabricated by a non-fluorinated coating technique that consisted of polydimethylsiloxane (PDMS) grafted Fe3O4 particle, PDMS grafted halloysite nanotubes, and PDMS binder. The coated sponge achieved excellent mechanically durable and chemically stable superhydrophobicity that resisted a series of severe treatments. It was unquestionable to show very fast oil absorption. What's more, it especially showed very high adsorption capacity (24.3-48.2 mg/g) and could quickly adsorb almost 100% MPs (polypropylene, polyvinyl chloride, and polyethylene) from aqueous suspensions. Moreover, the removal rates remained almost 100% for these MPs after 50 cycles. Besides, the coated sponge had excellent salt tolerance and antibacterial activity to Escherichia coli (E. coli) (99.91%) and Staphylococcus aureus (S. aureus) (90.46%). The adsorption mechanism of the coating was discussed from the perspectives of molecular structure, electronic effect, steric hindrance, and size-scale effect. The absorption driving force mainly derived from the intra-particle diffusion under capillary attraction, whilst slight electrostatic interaction, hydrogen bond interaction, and σ-p (or p-p) conjugation between PDMS and MPs. This functional sponge was destined to be a new strategy in the removal of MPs and other solid pollutants, especially in the high-salinity and rich-microorganism water environment.
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Microplásticos , Plásticos , Escherichia coli , Interações Hidrofóbicas e Hidrofílicas , Plásticos/química , Staphylococcus aureus , Água/químicaRESUMO
BACKGROUND: To compare endothelial loss between recipients who received viral DNA-positive grafts and controls 2 years after corneal transplantation. METHODS: We retrospectively analysed the clinical data and endothelial cell density of recipients of viral DNA-positive grafts and age-, sex-, aetiology- and operation-matched controls from April 2017 to July 2019 at the Peking University Third Hospital, Beijing, China. RESULTS: A total of 23/942 (2.44%) donor corneal buttons tested virus-positive by real-time PCR. A total of 27 recipients (except for 2 recipients) of viral DNA-positive grafts and 48 recipients of viral DNA-negative grafts were included in this study. Recipients of viral DNA-positive grafts had a higher endothelial cell (EC) loss rate post-penetrating keratoplasty and post-descemet stripping automated endothelial keratoplasty (p<0.05), but post-deep lamellar keratoplasty, the EC loss rate was similar to that of the controls. Recipients of herpes simplex virus-1-, cytomegalovirus- and varicella-zoster virus-positive grafts all had a higher EC loss rate than the controls during the 12- and 24-month follow-up periods (p<0.05). CONCLUSION: We inferred that viruses might be hidden in corneal grafts and mainly incubate in the corneal endothelium. Viral DNA-positive grafts do not need to be replaced immediately and can be followed up for a long time.
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Doenças da Córnea , Transplante de Córnea , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Doenças da Córnea/cirurgia , DNA Viral/genética , Células Endoteliais , Endotélio Corneano/cirurgia , Seguimentos , Humanos , Ceratoplastia Penetrante , Estudos RetrospectivosRESUMO
OBJECTIVE: To evaluate the condition of meibomian glands in dry eye patients. METHODS: Non interventional, observational study. 388 eyes from 194 patients which were diagnosed as dry eye during March to December 2010 were collected, 69 males (138 eyes), 125 females (250 eyes). Patients' age range 7-85 years, mean (44±18) years. Symptom score, Schirmer test Ia (SIaT), tear film break-up time (BUT) and superficial punctuated keratopathy were measured. The meibomian glands were observed using the noncontact meibography system. RESULTS: In all subjects, symptom score 5.47±2.14, SIaT (5.58±4.22) mm, BUT (3.09±2.34) s, superficial punctuated keratopathy score 4.10±3.79. Meibo-score: 1 point, 3.09% (12 eyes); 2 points, 9.28% (36 eyes); 3 points, 20.10% (78 eyes); 4 points, 26.03% (101 eyes); 5 points, 21.91% (85 eyes); 6 points, 19.59% (76 eyes). CONCLUSIONS: Abnormal meibomian glands occupied a extremely high proportion of dry eye which indicate that meibomian glands disorder plays important role in dry eye. Noncontact meibography system could show accurate structure of meibomian glands.
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Síndromes do Olho Seco/diagnóstico , Glândulas Tarsais , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Técnicas de Diagnóstico Oftalmológico , Síndromes do Olho Seco/diagnóstico por imagem , Feminino , Humanos , Raios Infravermelhos , Masculino , Glândulas Tarsais/diagnóstico por imagem , Pessoa de Meia-Idade , Radiografia , Adulto JovemRESUMO
OBJECTIVE: To evaluate the effect and explore the complications of Descemet-stripping automated endothelial keratoplasty (DSAEK) combined with phacoemulsification cataract surgery or lens exchange in corneal endothelial dysfunction eyes with lens disorders. METHODS: Retrospective case series. Eighteen consecutive cases (20 eyes) were performed DSAEK combined with lens surgery from December 2007 to December 2008 in Department of Ophthalmology, Peking University Third Hospital. Five cases (7 eyes) were performed DSAEK combined with phacoemulsification and intraocular lens (IOL) insertion. Seven cases were combined with anterior chamber IOL extraction, anterior vitrectomy and posterior chamber IOL insertion. Six aphakia cases were performed with DSAEK combined with anterior vitrectomy and sclera fixation posterior chamber IOL insertion. Postoperatively, the visual acuity, corneal transparency, central corneal thickness (CCT), endothelial cell density (ECD) and complications were observed during the follow-up. RESULTS: The irritation was disappeared in all of patients. All of the corneas became transparent. The preoperative and postoperative mean CCT of the recipient beds was 859 µm and 553 µm respectively. T value was 5.303 (t = 5.303, P < 0.01). It was extremely significant difference. The mean ECD of the donors was 2987 cells/mm(2). The ECD was 1803 cells/mm(2) in three months postoperatively. The rate of endothelial cells loss was 41%. The visual acuity improved significantly except 9 eyes which had fundus disorders. Six eyes were better than 0.8. It was 55% in normal retinal function patients (6/11). The inflammatory reaction of the anterior chamber IOL eyes was most serious. Six eyes underwent graft dislocation. Five cases underwent high intraocular pressure. One case occurred graft rejection. These complications occurred in anterior chamber IOL eyes. CONCLUSIONS: DSAEK combined with phacoemulsification cataract surgery or lens exchange is a safe and effective surgical treatment for corneal endothelial dysfunction with lens disorders. More complications occur in anterior chamber IOL eyes. DSAEK should be cautiously chosen in abnormal iris and chamber angle structural eyes.
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Catarata/terapia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Implante de Lente Intraocular , Facoemulsificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Endotélio Corneano/transplante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
To achieve the requirements of modified bismaleimide resin composites in electronic industry and high energy storage devices, flame retardancy, water resistance and dielectric properties must be improved. Hence, a highly efficient multifunctional graphene nanoplatelets hybrid flame retardant is prepared by ionic liquid graphite and ammonium polyphosphate. The preparation processes of the flame retardants are simple, low energy consumption and follow the green chemical concept of 100% utilization of raw materials, compared with chemical stripping. The bismaleimide resin containing 10 wt.% of the flame retardant show good flame retardancy, resulting in the limiting oxygen index increases to above 43%, and the peak heat release rate, total heat release and total smoke release decrease by 41.8%, 47.8% and 52.3%, respectively. After soaking, mass loss percentage of the modified bismaleimide resin only decreases by 0.96%, the dielectric constant of the composite increases by 39.4%, and the dielectric loss decreases with the increase of frequency. The hybrid flame retardants show multifunctional effect in the modified bismaleimide resin, due to the physical barrier, the chemical char-formation, hydrophobicity and strong conductivity attributed to co-work of Graphene nanoplatelets, ammonium polyphosphate and ionic liquid.
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Delicately regulating the distribution morphology of a filler is an effective strategy to promote the separation performance of mixed matrix membranes (MMMs). Herein, we describe a highly permeable metal-organic framework (MOF)-based MMM comprising vertically aligned ZIF-8 (V-ZIF-8) and polysulfone (PSF). The V-ZIF-8 is distributed uniformly within the PSF matrix. With this unique distribution morphology of ZIF-8, the shortest gas transport pathways are formed in the membrane. Meanwhile, the molecular-sieving pores of ZIF-8 can allow CO2 to pass through and crowding out N2. The obtained V-ZIF-8/PSF membrane shows a high CO2 permeability of 89.7 Barrer and a CO2/N2 selectivity of 30.0 that is stable over a period of 50 h. The CO2 permeability is enhanced about 11.8 times than that of the pure PSF membrane. The results prove that the vertically aligned distribution morphology of an MOF in a polymer matrix is an effective method to improve the separation performance of a membrane, providing a new concept for designing more advanced membranes.
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Chitosan-modified zinc hydroxystannate (ZHS-CS) was synthesized using the cations of the biomaterial chitosan (CS) and ion replacement strategy. A ZHS-CS and reduced graphene oxide (rGO) hybrid flame retardant (ZHS-CS/rGO) was synthesized for use in flexible poly (vinyl chloride) (PVC). Scanning electron microscopy images indicated that ZHS-CS and rGO were evenly dispersed in ZHS-CS/rGO without agglomeration. Fourier transform infrared spectroscopy results showed that rGO was fully reduced. The flame-retardant and mechanical properties of PVC composites were investigated using the limiting oxygen index (LOI), a cone calorimeter, and mechanical equipment. By replacing one-fifth of the zinc ions in ZHS by chitosan cations to obtain Sn-4Zn-1CS/rGO, the ZHS-CS/rGO was found to improve PVC composite performance. The total heat release and total smoke release of PVC/Sn-4Zn-1CS/rGO were reduced by 24.2 and 40.0 %, respectively, from those of pure PVC.
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Quitosana/química , Grafite/síntese química , Cloreto de Polivinila/química , Compostos de Estanho/química , Zinco/química , Materiais Biocompatíveis/química , Retardadores de Chama , Grafite/química , Microscopia Eletrônica de Varredura , Óxidos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Temperatura , Resistência à Tração , Compostos de Zinco , Óxido de ZincoRESUMO
The human retina is a complex neural tissue that detects light and sends visual information to the brain. However, the molecular and cellular processes that underlie aging primate retina remain unclear. Here, we provide a comprehensive transcriptomic atlas based on 119 520 single cells of the foveal and peripheral retina of humans and macaques covering different ages. The molecular features of retinal cells differed between the two species, suggesting distinct regional and species specializations of the human and macaque retinae. In addition, human retinal aging occurred in a region- and cell-type-specific manner. Aging of human retina exhibited a foveal to peripheral gradient. MYO9A- rods and a horizontal cell subtype were greatly reduced in aging retina, indicating their vulnerability to aging. Moreover, we generated a dataset showing the cell-type- and region-specific gene expression associated with 55 types of human retinal disease, which provides a foundation to understanding of the molecular and cellular mechanisms underlying human retinal diseases. Such datasets are valuable to understanding of the molecular characteristics of primate retina, as well as molecular regulation of aging progression and related diseases.
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PURPOSE: To report the long-term outcomes of Descemet stripping endothelial keratoplasty (DSEK) with suture-assisted donor lenticule insertion performed in different age groups for pediatric patients with congenital hereditary endothelial dystrophy (CHED). DESIGN: Retrospective case series. METHODS: Pediatric patients with CHED who underwent DSEK from January 2010 to January 2016 were enrolled. Patients were divided into 2 groups according to their ages: the infant group and the child group. Long-term clinical outcomes and complications were compared. RESULTS: Thirty eyes of 16 patients were included: 19 eyes (10 patients) in the child group and 11 eyes (6 patients) in the infant group. The average duration of follow-up was 4.08 ± 1.90 years (range 2.5-8.5 years). Corneal transparency scores of the 2 groups on postoperative day 7 were not statistically different. The average postoperative best-corrected visual acuity (BCVA) in the infant group (logMAR 0.32 ± 0.11) was better than that in the child group (logMAR 0.54 ± 0.20; (P = .01). Thirty-three percent of cases in the child group and 86% of cases in the infant group had postoperative BCVA achieved or better than logMAR 0.4. Average endothelial cell loss in the child group was 31.21% ± 9.17%. Lenticule detachment occurred in 3 cases in the child group. CONCLUSIONS: Improved visual outcomes could be achieved in infant patients with CHED after DSEK without significant complications. Suture-assisted donor lenticule insertion techniques, Descemet membrane stripping, and postoperative sedation are advocated technical points.
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Distrofias Hereditárias da Córnea/cirurgia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Endotélio Corneano/cirurgia , Adolescente , Criança , Pré-Escolar , Distrofias Hereditárias da Córnea/fisiopatologia , Endotélio Corneano/fisiopatologia , Feminino , Humanos , Lactente , Pressão Intraocular/fisiologia , Masculino , Estudos Retrospectivos , Microscopia com Lâmpada de Fenda , Resultado do Tratamento , Acuidade Visual/fisiologiaRESUMO
Novel core-shell graphitic carbon nitride/zinc phytate (g-C3N4/PAZn) flame retardant was simple synthetized using two-dimensional g-C3N4 and bio-based PAZn by self-assembly and incorporated into epoxy resin (EP) for improving the fire safety. The flame retardance and smoke suppression were investigated by cone calorimetry. The results indicated that g-C3N4/PAZn-EP displayed outstanding flame retardancy and smoke suppression, for example, the peak heat release rate and peak smoke production rate decreased by 71.38% and 25%, respectively. Furthermore, the flame retardancy mechanism was further explored by char residue and thermal stability analysis. It can be predicted that g-C3N4/PAZn will provide valuable reference about bio-based flame retardant.
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Metal-organic frameworks (MOFs) exhibit highly designable properties and have been used in wide applications. To further improve their performance, the modification of MOFs is an effective method. However, the modification process is usually complicated. Besides, the sustainable use of MOFs is difficult to achieve due to the complicated recycling treatment. Herein, we designed a polyethyleneimine (PEI)-modified NH2-MIL-101(Al) composite (PEI@NH2-MIL-101(Al)). This composite showed excellent dye removal performance of methyl orange (MO, 89.4%) and Direct Red 80 (DR80, 99.8%). Remarkably, the dye removal application of PEI@NH2-MIL-101(Al) also acted as a modification process toward flame retardant application. Thus, the dye-adsorbed PEI@NH2-MIL-101(Al) composite (MO-PEI@NH2-MIL-101(Al) and DR80-PEI@NH2-MIL-101(Al)) was sustainably used as an effective flame retardant for an epoxy resin (EP) at low additions (4.0 wt %). The limiting oxygen values of EP/MO-PEI@NH2-MIL-101(Al) and EP/DR80-PEI@NH2-MIL-101(Al) increased to 26.5 and 26.7%, respectively. The heat release and the smoke production of dyes-PEI@NH2-MIL-101(Al)/EP were greatly reduced compared with those of EP. This strategy provides a simple and effective modification method for MOFs. Meanwhile, the modified MOF composite can achieve sustainable application, giving full play to the advantages of MOFs.
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A novel compound containing active amine groups of polyphosphazene (PBFA) was successfully synthesized and applied as a reactive flame-retardant additive in epoxy (EP) resin. It was synthesized from N-aminoethylpiperazine and hexachlorocyclotriphosphazene using a simple method, and its structure was well-characterized. The results indicated that introducing PBFA into EP composites significantly improves the resistance to fire and suppresses smoke generation. An EP composite with 9.0 wt% PBFA can pass the vertical burning tests V-0 rating, the peak heat release rate and total heat release of the sample decreased by 46.7% and 29.3%, respectively. Moreover, it decreased the total smoke release by 48.0%. Thermogravimetric analysis showed that the presence of PBFA can accelerate EP decomposition at comparatively low temperatures and lead to the formation of a stable char layer, which protects the matrix from fire, therefore improving the amount of char residue at 800 °C. The degree of small molecule degradation characterized by gas chromatograph/mass spectrometer, which was lower than that of pure EP, demonstrating that PBFA reduces the risk of fire. The glass transition temperature of EP composites increased with the amount of PBFA increasing owing to the presence of active amine groups. Notably, its mechanical properties were not degraded.