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1.
Matrix Biol ; 128: 21-30, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38340967

RESUMO

Patients with classical Ehlers Danlos syndrome (cEDS) suffer impaired wound healing and from scars formed after injuries that are atrophic and difficult to close surgically. Haploinsufficiency in COL5A1 creates systemic morphological and functional alterations in the entire body. We investigated mechanisms that impair wound healing from corneal lacerations (full thickness injuries) in a mouse model of cEDS (Col5a1+/-). We found that collagen V reexpression in this model is upregulated during corneal tissue repair and that wound healing is delayed, impaired, and results in large atrophic corneal scars. We noted that in a matrix with a 50 % content of collagen V, activation of latent Transforming Growth Factor (TGF) ß is dysregulated. Corneal myofibroblasts with a haploinsufficiency of collagen V failed to mechanically activate latent TGF ß. Second harmonic imaging microscopy showed a disorganized, undulated, and denser collagen matrix in our Col5a1+/- model that suggested alterations in the extracellular matrix structure and function. We hypothesize that a regenerated collagen matrix with only 50 % content of collagen V is not resistant enough mechanically to allow adequate activation of latent TGF ß by fibroblasts and myofibroblasts.


Assuntos
Lesões da Córnea , Síndrome de Ehlers-Danlos , Anormalidades da Pele , Camundongos , Animais , Humanos , Síndrome de Ehlers-Danlos/genética , Síndrome de Ehlers-Danlos/metabolismo , Colágeno/metabolismo , Lesões da Córnea/genética , Cicatriz/genética , Fator de Crescimento Transformador beta
2.
Invest Ophthalmol Vis Sci ; 64(13): 9, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37796488

RESUMO

Purpose: In this study, we aim to elucidate functional differences between fibroblasts and myofibroblasts derived from a keratocyte lineage to better understand corneal scarring. Methods: Corneal fibroblasts, derived from a novel triple transgenic conditional KeraRT/tetO-Cre/mTmG mouse strain that allows isolation and tracking of keratocyte lineage, were expanded, and transformed by exposure to transforming growth factor (TGF)-ß1 to myofibroblasts. The composition and organization of a fibroblast-built matrix, deposited by fibroblasts in vitro, was analyzed and compared to the composition of an in vitro matrix built by myofibroblasts. Second harmonic generation microscopy (SHG) was used to study collagen organization in deposited matrix. Different extracellular matrix proteins, expressed by fibroblasts or myofibroblasts, were analyzed and quantified. Functional assays compared latent (TGF-ß) activation, in vitro wound healing, chemotaxis, and proliferation between fibroblasts and myofibroblasts. Results: We found significant differences in cell morphology between fibroblasts and myofibroblasts. Fibroblasts expressed and deposited significantly higher quantities of fibril forming corneal collagens I and V. In contrast, myofibroblasts expressed and deposited higher quantities of fibronectin and other non-collagenous matrix components. A significant difference in the activation of latent TGF-ß activation exists between fibroblasts and myofibroblasts when measured with a functional luciferase assay. Fibroblasts and myofibroblasts differ in their morphology, extracellular matrix synthesis, and deposition, activation of latent TGF-ß, and chemotaxis. Conclusions: The differences in the expression and deposition of extracellular matrix components by fibroblasts and myofibroblasts are likely related to critical roles they play during different stages of corneal wound healing.


Assuntos
Lesões da Córnea , Miofibroblastos , Animais , Camundongos , Fibroblastos , Ceratócitos da Córnea , Córnea , Camundongos Transgênicos , Fator de Crescimento Transformador beta
3.
Ocul Immunol Inflamm ; : 1-3, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37831890

RESUMO

PURPOSE: To report a rare case of non-granulomatous anterior uveitis (clinical, IVCM in vivo confocal microscopy, and anterior optical coherence tomography (OCT) findings) in a non-immunosuppressed patient with mpox infection. METHODS: A 24-year-old male was consulted for bilateral ocular pain, red eye, itchiness, and mucoid discharge. In his left eye, multiple vesicles and papules, some with central ulceration, were found in the superior and inferior eyelids. Mucoid discharge, chemosis, limbitis, and an anterior chamber reaction were also found. A conjunctival PCR swab for mpox was positive. The patient was treated with topical steroids with a good response. RESULTS: OCT and IVCM showed sub-endothelial deposits, stromal edema, hyperreflective multinucleated images in the epithelial layer, activated stromal images, and stromal edema characterized by fusiform hyperreflectivity that was resolved with the proposed treatment. CONCLUSIONS: This is the first report of OCT and IVCM in a non-immunosuppressed patient with mpox infection with a good response to topical steroids.

4.
Dis Model Mech ; 16(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37702214

RESUMO

Every tissue has an extracellular matrix (ECM) with certain properties unique to it - the tissue 'niche' - that are necessary for normal function. A distinct specific population of quiescent keratocan-expressing keratocytes populate the corneal stroma during homeostasis to maintain corneal function. However, during wound healing, when there is alteration of the niche conditions, keratocytes undergo apoptosis, and activated corneal fibroblasts and myofibroblasts attempt to restore tissue integrity and function. It is unknown what the fate of activated and temporary fibroblasts and myofibroblasts is after the wound healing process has resolved. In this study, we used several strategies to elucidate the cellular dynamics of corneal wound healing and the fate of corneal fibroblasts. We injured the cornea of a novel mouse model that allows cell-lineage tracing, and we transplanted a cell suspension of in vitro-expanded corneal fibroblasts that could be tracked after being relocated into normal stroma. These transplanted fibroblasts regained expression of keratocan in vivo when relocated to a normal stromal niche. These findings suggest that transformed fibroblasts maintain plasticity and can be induced to a keratocyte phenotype once relocated to an ECM with normal signaling ECM.


Assuntos
Córnea , Fibroblastos , Animais , Camundongos , Apoptose , Divisão Celular , Matriz Extracelular
5.
Ocul Surf ; 28: 115-123, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36871831

RESUMO

PURPOSE: Corneal melting and perforation are feared sight-threatening complications of infections, autoimmune disease, and severe burns. Assess the use of genipin in treating stromal melt. METHODS: A model for corneal wound healing was created through epithelial debridement and mechanical burring to injure the corneal stromal matrix in adult mice. Murine corneas were then treated with varying concentrations of genipin, a natural occurring crosslinking agent, to investigate the effects that matrix crosslinking using genipin has in wound healing and scar formation. Genipin was used in patients with active corneal melting. RESULTS: Corneas treated with higher concentrations of genipin were found to develop denser stromal scarring in a mouse model. In human corneas, genipin promoted stromal synthesis and prevention of continuous melt. Genipin mechanisms of action create a favorable environment for upregulation of matrix synthesis and corneal scarring. CONCLUSION: Our data suggest that genipin increases matrix synthesis and inhibits the activation of latent transforming growth factor-ß. These findings are translated to patients with severe corneal melting.


Assuntos
Lesões da Córnea , Perfuração da Córnea , Humanos , Camundongos , Animais , Cicatriz/patologia , Córnea , Substância Própria/patologia , Lesões da Córnea/patologia , Matriz Extracelular
6.
Exp Eye Res ; 230: 109456, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36967080

RESUMO

The role of collagen XII in regulating injury repair and reestablishment of corneal function is unknown. This manuscript aims to investigate the role(s) of collagen XII in the repair of incisional and debridement injuries in an adult mouse model. Two different types of injury in wild type and Col12a1-/- corneas were created to investigate the effects of collagen XII -in wound repair and scar formation-by using clinical photographs, immunohistology, second harmonic generation imaging and electron microscopy. Results showed that collagen XII is a regulator of wound closure after incisional injuries. Absence of collagen XII retarded wound closure and the wound healing process. These findings show that collagen XII regulates fibrillogenesis, CD68 cell lineage infiltration, and myofibroblast survival following injury. In vitro studies suggest that collagen XII regulates deposition of an early and provisional matrix by interacting with two proteins regulating early matrix deposition: fibronectin and LTBP1(latent transforming growth factor ß binding protein 1). In conclusion, collagen XII regulates tissue repair in corneal incisional wounds. Understanding the function of collagen XII during wound healing has significant translational value.


Assuntos
Colágeno , Lesões da Córnea , Animais , Camundongos , Colágeno/metabolismo , Córnea/metabolismo , Cicatriz/metabolismo , Lesões da Córnea/metabolismo , Microscopia Eletrônica
7.
J Steroid Biochem Mol Biol ; 225: 106200, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36272497

RESUMO

Lanosterol, an oxysterol molecule, has been proposed to help maintain lens transparency by inhibiting the formation of protein aggregates. This sterol is produced by the enzyme lanosterol synthase and is part of a metabolic pathway that forms cholesterol as a final step. Abnormalities in lanosterol synthase are responsible for congenital cataracts. The αA-crystallin protein, which acts as a molecular chaperone to lanosterol synthase, has been reported to have anti-protein aggregation, anti-inflammatory and anti-apoptotic properties. In this work, we evaluated the correlation of lanosterol synthase and αA-crystallin in human cataractous lenses with the grade of opacity, as well as the expression of lanosterol synthase, farnesyl DPP, geranyl synthase and squalene epoxidase genes. Lanosterol synthase and αA-crystallin were overexpressed in cataractous lenses as well as farnesyl-DP synthase, squalene epoxidase, lanosterol synthase and geranyl synthase genes in cataratous lenses in comparison with normal lenses. Our data confirm that lanosterol synthase and the sterol pathway are upregulated in cataractous lenses. This argues for a functional role of the oxysterol pathway and its products as an important mediator in the pathogenesis of human cataracts.


Assuntos
Catarata , Cristalinas , Oxisteróis , Humanos , Esteróis , Esqualeno Mono-Oxigenase , Catarata/genética , Catarata/metabolismo , Catarata/patologia , Cristalinas/genética
8.
J Cell Sci ; 135(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34854919

RESUMO

Collagen XI plays a role in nucleating collagen fibrils and in controlling fibril diameter. The aim of this research was to elucidate the role that collagen XI plays in corneal fibrillogenesis during development and following injury. The temporal and spatial expression of collagen XI was evaluated in C57BL/6 wild-type mice. For wound-healing studies in adult mice, stromal injuries were created using techniques that avoid caustic chemicals. The temporal expression and spatial localization of collagen XI was studied following injury in a Col11a1 inducible knockout mouse model. We found that collagen XI expression occurs during early maturation and is upregulated after stromal injury in areas of regeneration and remodeling. Abnormal fibrillogenesis with new fibrils of heterogeneous size and shape occurs after injury in a decreased collagen XI matrix. In conclusion, collagen XI is expressed in the stroma during development and following injury in adults, and is a regulator of collagen fibrillogenesis in regenerating corneal tissue.


Assuntos
Colágeno , Córnea , Animais , Colágeno/genética , Colágeno/metabolismo , Córnea/metabolismo , Regulação para Baixo/genética , Camundongos , Camundongos Endogâmicos C57BL , Regulação para Cima/genética
9.
Am J Pathol ; 192(2): 308-319, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34774848

RESUMO

Collagen XII is a regulator of corneal stroma structure and function. The current study examined the role of collagen XII in regulating corneal stromal transforming growth factor (TGF)-ß activation and latency. Specifically, with the use of conventional collagen XII null mouse model, the role of collagen XII in the regulation of TGF-ß latency and activity in vivo was investigated. Functional quantification of latent TGF-ß in stromal matrix was performed by using transformed mink lung reporter cells that produce luciferase as a function of active TGF-ß. Col12a1 knockdown with shRNA was used to test the role of collagen XII in TGF-ß activation. Col12a1-/- hypertrophic stromata were observed with keratocyte hyperplasia. Increased collagen fibril forward signal was found by second harmonic generation microscopy in the absence of collagen XII. Collagen XII regulated mRNA synthesis of Serpine1, Col1a1, and Col5a1 and deposition of collagens in the extracellular matrix. A functional plasminogen activator inhibitor luciferase assay showed that collagen XII is necessary for latent TGF-ß storage in the extracellular matrix and that collagen XII down-regulates active TGF-ß. Collagen XII dictates stromal structure and function by regulating TGF-ß activity. A hypertrophic phenotype in Col12a1-/- corneal tissue can be explained by abnormal up-regulation of TGF-ß activation and decreased latent storage.


Assuntos
Colágeno Tipo XII/metabolismo , Substância Própria/metabolismo , Queratinócitos/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Colágeno Tipo XII/genética , Substância Própria/patologia , Queratinócitos/patologia , Camundongos , Camundongos Knockout , Fator de Crescimento Transformador beta/genética
10.
Am J Pathol ; 191(12): 2184-2194, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34560063

RESUMO

Collagen XIV is poorly characterized in the body, and the current knowledge of its function in the cornea is limited. The aim of the current study was to elucidate the role(s) of collagen XIV in regulating corneal stromal structure and function. Analysis of collagen XIV expression, temporal and spatial, was performed at different postnatal days (Ps) in wild-type C57BL/6 mouse corneal stromas and after injury. Conventional collagen XIV null mice were used to inquire the roles that collagen XIV plays in fibrillogenesis, fibril packing, and tissue mechanics. Fibril assembly and packing as well as stromal organization were evaluated using transmission electron microscopy and second harmonic generation microscopy. Atomic force microscopy was used to assess stromal stiffness. Col14a1 mRNA expression was present at P4 to P10 and decreased at P30. No immunoreactivity was noted at P150. Abnormal collagen fibril assembly with a shift toward larger-diameter fibrils and increased interfibrillar spacing in the absence of collagen XIV was found. Second harmonic generation microscopy showed impaired fibrillogenesis in the collagen XIV null stroma. Mechanical testing suggested that collagen XIV confers stiffness to stromal tissue. Expression of collagen XIV is up-regulated following injury. This study indicates that collagen XIV plays a regulatory role in corneal development and in the function of the adult cornea. The expression of collagen XIV is recapitulated during wound healing.


Assuntos
Colágeno/fisiologia , Substância Própria/fisiologia , Substância Própria/ultraestrutura , Envelhecimento/fisiologia , Animais , Colágeno/genética , Córnea/diagnóstico por imagem , Córnea/metabolismo , Córnea/ultraestrutura , Paquimetria Corneana , Substância Própria/diagnóstico por imagem , Substância Própria/patologia , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Microscopia de Geração do Segundo Harmônico , Tomografia de Coerência Óptica
11.
Transl Vis Sci Technol ; 10(9): 25, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34424287

RESUMO

Purpose: To evaluate the use of genipin in delaying enzymatic digestion of corneal stroma. Methods: Human corneal stromal tissue was treated with genipin, a known chemical crosslinker, and then along with control tissue was subjected to enzymatic digestion with collagenase. The effects of genipin treatment in retarding stromal digestion were analyzed with phase contrast microscopy, a protein quantification assay, second harmonic generation imaging, and transmission electron microscopy. Results: Genipin increased stromal resistance to enzymatic digestion when compared with untreated stroma. A morphologic analysis and protein quantification showed increased stromal resistance to enzymatic digestion once stromal tissue was treated with genipin. Second harmonic generation imaging revealed persistent fibrillar collagen signaling in genipin-treated tissue in contrast with untreated tissue suggesting that genipin retards collagenolysis. Conclusions: Genipin increases stromal resistance to enzymatic digestion in controlled experiments as demonstrated by protein quantification studies and through morphologic imaging. Translational Relevance: This study explores the novel use of genipin in delaying enzymatic stromal digestion. Delaying stromal melting in the setting of corneal infectious or autoimmune keratitis can potentially decrease clinical morbidity.


Assuntos
Colágeno , Substância Própria , Reagentes de Ligações Cruzadas , Digestão , Humanos , Iridoides
12.
Cont Lens Anterior Eye ; 44(6): 101453, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33972176

RESUMO

PURPOSE: A systematic review and meta-analysis was performed to evaluate the effectiveness of interventions in the treatment ofDemodex blepharitis in adult patients. METHODS: A systematic review and meta-analysis of studies reporting the efficacy of treatments forDemodex blepharitis in the main databases (PubMed / Scopus / Cochrane / EMBASE / Science Direct / WOS / Scielo / Google Scholar / metaRegister of Controlled Trials / ClinicalTrials.gov/ WHO ICTRP) until November 24, 2020 was performed according to the PRISMA statement for meta-analysis. RESULTS: Overall, 18 studies were included for 29 different interventions in 1195 participants with 1574 eyes that were positive for Demodex Spp. Demodex counts, total eradication, clinical improvement, Ocular Surface Disease Index, Tear Break-Up Time, cylindrical dandruff, Schirmer test, osmolarity and adverse reactions were analysed, and stratified sub-analyses conducted. The overall effects for Demodex count (mean difference), total eradication (risk ratio) and adverse reactions (risk difference) were -2.07 (95 % CI -3.99 to -0.15) p = 0.03, 1.84 (95 % CI 1.27-2.66) p = 0.001 and 0.24 (95 % CI 0.08 to 0.41) p = 0.005, respectively. The most frequent interventions evaluated in the included studies were tea tree oil (TTO) and its derivatives, such as terpinen 4-ol. CONCLUSION: Multiple therapeutic choices were evaluated in this meta-analysis. Pharmacological interventions were superior to non-pharmacological (mechanical, thermal and pulsed light) interventions. It was not possible to establish significant differences between TTO and non-TTO-derived treatments. Adverse reactions were more frequent in TTO-derived treatments, however all were mild. It is necessary to execute studies with longer follow-up times to determine whether re-infestation occurs after the administration of different treatments.


Assuntos
Blefarite , Infecções Oculares Parasitárias , Pestanas , Infestações por Ácaros , Ácaros , Adulto , Animais , Blefarite/diagnóstico , Blefarite/tratamento farmacológico , Infecções Oculares Parasitárias/diagnóstico , Infecções Oculares Parasitárias/tratamento farmacológico , Humanos , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/tratamento farmacológico
13.
Int Ophthalmol ; 41(6): 2179-2185, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33725268

RESUMO

PURPOSE: To evaluate the visual outcomes, visual performance, and stereoacuity in presbyopic patients following treatment by a change in the corneal asphericity and micro-monovision. METHODS: Presbyopic patients with diverse refractive errors and emmetropes (n = 30 eyes) were treated with a custom Q-ablation profile and micro-monovision in the non-dominant eye. There with a difference of Q - 0.30 in the Q profiles between dominant and non-dominant eyes. Patients were assigned in two groups based on the preoperative spherical equivalent (Group 1 + 4.00 to + 0.50, and group 2 neutral to - 3.00). Binocular uncorrected distance visual acuity (binocular UCVA), best-corrected visual acuity (BCVA), binocular uncorrected near visual acuity (binocular UNVA) preoperative and postoperative, spherical equivalent refraction, contrast sensitivity, and stereopsis were analyzed at 1, 3, and 6 months. RESULTS: The mean age was 52.6 ± 5.1 (SD) years. At six months post-operation, the mean binocular uncorrected distance visual acuity (binocular UDVA) was 0.15 ± 0.04 logMAR (20/25-) in group 1, and 0.11 ± 0.05 logMAR (20/25) in group 2, and binocular uncorrected near vision UNVA was 0.5 ± 0.1 M (20/25 J2) in group 1 and 0.45 ± 0.2 M (20/25 J2) group 2. An increase in stereoacuity was found in both groups. CONCLUSIONS: The correction of refractive defects using customized corneal asphericity was an effective treatment in presbyopic patients. Furthermore, the treatment was well tolerated in this group of patients. Following surgery, the quality of vision was adequate, and the stereovision improved in this cohort of patients.


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ , Presbiopia , Topografia da Córnea , Humanos , Lasers de Excimer , Pessoa de Meia-Idade , Presbiopia/cirurgia , Refração Ocular , Visão Binocular , Visão Monocular
14.
Cont Lens Anterior Eye ; 44(3): 101326, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32461053

RESUMO

PURPOSE: To evaluate the efficacy of topical ivermectin-metronidazole combined therapy in the management of Demodex-associatedblepharitis. METHODS: Sixty patients with a diagnosis of Demodex-associatedblepharitis were recruited in a randomized clinical trial. Thirty receiving topical ivermectin (0.1%)-metronidazole (1%) gel treatment on days 0, 15 and 30. Thirty additional patients were used as a control group receiving vehicle on days 0, 15 and 30. The primary efficacy measure was the number of Demodex spp. mitesin the eyelashes of patients. The secondary outcomes included clinical improvement of signs and adverse events. RESULTS: Complete eradication of Demodex spp. was found in 96.6% of patients in the treatment group. Furthermore, a significant reduction of inflammation signs were found in all treated patients versus controls. None of the patients experienced any adverse effects associated with the treatment. CONCLUSION: Demodex infection was controlled satisfactorily with the ivermectin (0.1%)-metronidazole (1%) gel, and no adverse effects were observed. Application of this gel for the treatment of different parasitic infections of the eyelids could be feasible, and this requires further exploration.


Assuntos
Blefarite , Pestanas , Infestações por Ácaros , Blefarite/diagnóstico , Blefarite/tratamento farmacológico , Humanos , Ivermectina , Metronidazol , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/tratamento farmacológico , Infestações por Ácaros/epidemiologia
15.
BioTechnologia (Pozn) ; 102(2): 141-155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36606026

RESUMO

The use of biotechnological approaches to increase soil fertility and productivity allows to obtain sustainable agriculture with lesser use of chemical fertilizers. The present study aimed to determine whether the inoculation of Bacillus panthothenicus, Bacillus thuringiensis, Pseudomonas putida, Pseudomonas syringae, or Serratia marcescens combined with reduced doses of NPK (nitrogen, phosphorus, potassium) fertilizer can improve the growth and yield of maize on poor ferruginous soils under field conditions in central Benin. For this purpose, maize seeds of the EVDT 97 STR C1 variety were inoculated with 10 ml suspension of five plant growth-promoting rhizobacteria (PGPR) strains, and the plots were fertilized at seeding with the recommended doses (0, 25, 50, 100%) of 200 kg/ha of NPK and 100 kg of urea for corn cultivation. The study was conducted in a completely randomized design with 3 replicates. The results showed that except for P. syringae , which induced the highest fresh aerial biomass (94.51%) and dry aerial biomass (63.63%), all other parameters were positively improved with inoculation associated with reduced doses of NPK + urea. The best height, leaf area, fresh underground biomass, and grain yield were recorded in response to the application of P. syringae + 50% NPK + urea, with an increase of 26.82, 32.23, 107.57, and 30.64%, respectively, compared to those of the control. The inoculation of seeds with P. syringae + 50% NPK + urea can be considered to be an environmentally sustainable strategy for maize cultivation.

16.
Br J Ophthalmol ; 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29970389

RESUMO

BACKGROUND: To evaluate the effectiveness of platelet-rich plasma (PRP) injections in the treatment of severe dry eye. METHODS: This prospective, intervention study included patients with severe dry eye who had been diagnosed with Sjogren syndrome. Patients were divided into two groups. The intervention group received PRP (n=15) injections on days 0, 30, 60 and 90, as well as hyaluronic acid five times per day. The comparison group received hyaluronic acid (n=15) five times per day. Subjects were measured at baseline and at 30, 60 and 90 days. The primary outcome measures were changes in corneal staining according to the Oxford classification, results of the Schirmer test and tear break-up time (TBUT). The secondary outcome measures were changes in the Ocular Surface Disease Index (OSDI) and treatment compliance. RESULTS: All subjects completed the study. The intervention group showed improvements in all primary outcome measures when compared with the control group, including a reduction in corneal staining (p<0.001), increase in the mean Schirmer value from 5.6±0.7 to 9.0±1.1 mm, and an increase in TBUT from 4.0±0.4 to 6.4±0.4 s at day 90. An improvement in subjective OSDI values was also found. CONCLUSION: PRP injection is safe and effective in improving tear parameters as well as subjective parameters, and was found to be superior to hyaluronic acid alone in the management of patients with severe dry eye. This represent a novel alternative treatment for severe dry eye. TRIAL REGISTRATION NUMBER: NCT02257957.

17.
New Phytol ; 214(3): 1188-1197, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28052459

RESUMO

Phloem sap contains a large number of macromolecules, including proteins and RNAs from different classes. Proteome analyses of phloem samples from different plant species under denaturing conditions identified hundreds of proteins potentially involved in diverse processes. Surprisingly, these studies also found a significant number of ribosomal and proteasomal proteins. This led to the suggestion that active ribosome and proteasome complexes might be present in the phloem, challenging the paradigm that protein synthesis and turnover are absent from the enucleate sieve elements of angiosperms. However, the existence of such complexes has as yet not been demonstrated. In this study we used three-dimensional gel electrophoresis to separate several protein complexes from native phloem sap from Brassica napus. Matrix-assisted laser desorption ionization-time of flight MS analyses identified more than 100 proteins in the three major protein-containing complexes. All three complexes contained proteins belonging to different ribosomal fragments and blue native northern blot confirmed the existence of ribonucleoprotein complexes. In addition, one complex contained proteasome components and further functional analyses confirmed activity of a proteasomal degradation pathway and showed a large number of ubiquitinated phloem proteins. Our results suggest specialized roles for ubiquitin modification and proteasome-mediated degradation in the phloem.


Assuntos
Brassica napus/metabolismo , Complexos Multiproteicos/metabolismo , Floema/metabolismo , Proteínas de Plantas/metabolismo , Ribonucleoproteínas/metabolismo , Peso Molecular , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Ribossomos/metabolismo , Proteínas Ubiquitinadas/metabolismo
18.
J Cataract Refract Surg ; 42(7): 1073-7, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27492108

RESUMO

PURPOSE: To evaluate the effect of genipin, a natural crosslinking agent, in rabbit eyes. SETTING: Department of Ophthalmology, Universidad Nacional de Colombia Centro de Tecnologia Oftalmica, Bogotá, Colombia. DESIGN: Experimental study. METHODS: Ex vivo rabbit eyes (16; 8 rabbits) were treated with genipin 1.00%, 0.50%, and 0.25% for 5 minutes with a vacuum device to increase corneal permeability. Penetration was evaluated using Scheimpflug pachymetry (Pentacam). In the in vivo model (20 rabbits; 1 eye treated, 1 eye with vehicle), corneas were crosslinked with genipin as described. Corneal curvature, corneal pachymetry, and intraocular pressure (IOP) assessments as well as slitlamp examinations were performed 0, 7, 30, and 60 days after treatment. RESULTS: In the ex vivo model, Scheimpflug pachymetry showed deep penetration in the rabbit corneas with an increase in corneal density and a dose-dependent relationship. Corneal flattening was observed in treated eyes (mean 4.4 diopters ± 0.5 [SD]) compared with the control eyes. Pachymetry and IOP were stable in all evaluations. No eye showed toxicity in the anterior chamber or in the lens. CONCLUSIONS: Corneal crosslinking induced by genipin produced significant flattening of the cornea with no toxicity in rabbit eyes. This crosslinking could be useful in the treatment of corneal ectasia and in the modification of corneal curvature. FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.


Assuntos
Córnea/química , Reagentes de Ligações Cruzadas/farmacologia , Iridoides/farmacologia , Animais , Paquimetria Corneana , Topografia da Córnea , Coelhos , Tonometria Ocular
19.
J Air Waste Manag Assoc ; 64(2): 235-46, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24654391

RESUMO

Chemical emissions from research and development (R&D) activities are difficult to estimate because of the large number of chemicals used and the potential for continual changes in processes. In this case study, stack measurements taken from R&D facilities at Pacific Northwest National Laboratory (PNNL) were examined, including extreme worst-case emissions estimates and alternate analyses using a Monte Carlo method that takes into account the full distribution of sampling results. The objective of this study was to develop techniques to estimate emissions from stack measurement data that take into account a high degree of variability in the actual emissions. The results from these analyses were then compared to emissions estimated from chemical inventories. Results showed that downwind ambient air concentrations calculated from the stack measurement data were below acceptable source impact levels (ASILs) for almost all compounds, even under extreme worst-case analyses. However for compounds with averaging periods of a year, the unrealistic but simplifying extreme worst-case analysis often resulted in calculated emissions that were above the lower level regulatory criteria used to determine modeling requirements or to define trivial releases. Compounds with 24-hr averaging periods were nearly all several orders of magnitude below all, including the trivial release, criteria. The alternate analysis supplied a more realistic basis of comparison and an ability to explore effects under different operational modes.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/legislação & jurisprudência , Simulação por Computador , Método de Monte Carlo , Pesquisa , Washington
20.
Cornea ; 33(1): 18-21, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24240491

RESUMO

PURPOSE: The aim was to evaluate the effect of autologous platelet-rich plasma on lacrimal function in patients with severe dry eye. METHODS: A prospective interventional case series design was adopted. Four patients with severe lacrimal dysfunction and severe dry eye were treated. Platelet rich-activated plasma (1 mL) was injected adjacent to the lacrimal gland on day 0 and at 4, 8, and 12 weeks. The objective parameters included a Schirmer test, ocular surface staining, and tear break-up time (TBUT). The patients were followed up for 12 weeks after the first injection. RESULTS: All cases showed a significant improvement in lacrimal volume (from 3.3 ± 0.8 mm to 11.1 ± 2.3 mm). In all the patients, an increase in tear break-up time values and a decrease in ocular staining (basal 8.0 ± 0.61-2.8 ± 0.5) with subjective improvement occurred. None of the patients presented any adverse effect, and none reported pain or discomfort. Additionally, no complications were observed. CONCLUSIONS: Injected platelet-enriched plasma was found to be safe and effective in increasing lacrimal production and in improving ocular staining secondary to severe dry eye. This approach could be an alternative for the management of these patients, although additional studies are required to perfect the technique.


Assuntos
Síndromes do Olho Seco/terapia , Doenças do Aparelho Lacrimal/terapia , Plasma Rico em Plaquetas , Adulto , Corantes , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/patologia , Feminino , Humanos , Injeções Intraoculares , Doenças do Aparelho Lacrimal/etiologia , Doenças do Aparelho Lacrimal/patologia , Corantes Verde de Lissamina , Masculino , Pessoa de Meia-Idade , Penfigoide Bolhoso/complicações , Estudos Prospectivos , Síndrome de Sjogren-Larsson/complicações , Síndrome de Stevens-Johnson/complicações , Lágrimas/metabolismo , Transplante Autólogo , Adulto Jovem
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