Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros

Base de dados
Ano de publicação
Tipo de documento
Intervalo de ano de publicação
1.
Biol Open ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39133170

RESUMO

The cephalopod eye lens is unique because it has evolved as a compound structure with two physiologically distinct segments. However, the detailed ultrastructure of this lens and precise optical role of each segment are far from clear. To help elucidate structure-function relationships in the cephalopod lens we conducted multiple structural investigations on squid. Synchrotron x-ray scattering and transmission electron microscopy disclose that an extensive network of structural features that resemble cell membrane complexes form a substantial component of both anterior and posterior lens segments. Optically, the segments are distinct, however, and Talbot interferometry indicates that the posterior segment possesses a noticeably higher refractive index gradient. We propose that the hitherto unrecognised network of membrane structures in the cephalopod lens has evolved to act as an essential conduit for the internal passage of ions and other metabolic agents through what is otherwise a highly dense structure owing to a very high protein concentration.

2.
Jpn J Ophthalmol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990388

RESUMO

PURPOSE: To assess the effectiveness of switching from the concomitant use of brinzolamide 1% (BZM) and brimonidine 0.1% (BMD) to a BZM/BMD fixed-dose combination (BBFC) for the reduction of corneal epithelial damage. STUDY DESIGN: Retrospective cohort study. METHODS: This study involved 52 eyes of 52 glaucoma patients (26 women, 26 men; mean age: 67.0 ± 14.0 years) followed for more than 3 months after being switched from concomitant BZM and BMD to BBFC. Superficial punctate keratitis (SPK) was assessed by fluorescein staining according to the National Eye Institute classification, with the cornea divided into 5 areas: center, superior, nasal, temporal, and inferior. SPK density was graded as 0 (no SPK), 1 (separate SPK), 2 (moderately dense SPK), and 3 (high SPK with overlapping lesions). SPK scores and intraocular pressure (IOP) at pre switching to BBFC (pre-BBFC) and at 3-months post switching to BBFC (post-BBFC) were then compared using the Wilcoxon signed-rank test. RESULTS: At pre-BBFC and post-BBFC, respectively, mean IOP was 12.4 ± 2.5 and 12.4 ± 2.7 mmHg, thus illustrating no significant difference in IOP between pre and post switch (p = 0.924), and the mean SPK score for center, superior, nasal, temporal, and inferior was 0.06 ± 0.24, 0.04 ± 0.19, 0.52 ± 0.67, 0.15 ± 0.36, and 0.92 ± 0.74, and 0.04 ± 0.19, 0.02 ± 0.14, 0.37 ± 0.56, 0.04 ± 0.19, and 0.75 ± 0.62, thus clearly showing a significant reduction in SPK scores for the nasal, temporal, and inferior areas at post-BBFC compared to those at pre-BBFC (p < 0.05). CONCLUSION: Our findings reveal that compared with the concomitant use of BZM and BMD, BBFC is effective in reducing corneal epithelial damage.

3.
JAMA Ophthalmol ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052247

RESUMO

Importance: Whether guttae in Fuchs endothelial corneal dystrophy (FECD) can be removed by polishing without Descemet stripping and whether postoperative maintenance of reduced guttae can be achieved through cultured corneal endothelial cell (CEC) transplant therapy are critical issues to be addressed. Objective: To investigate the decrease of guttae through polishing degenerated CECs and abnormal extracellular matrix (ECM) without Descemet stripping and to observe the behavior of guttae following cultured CEC transplant. Design, Setting, and Participants: This case series prospective observational study was conducted in a hospital outpatient clinic setting. Between December 2013 and January 2019, 22 eyes with corneal endothelial failure caused by FECD received cultured CEC transplant therapy at Kyoto Prefectural University Hospital. Of these, 15 eyes were consistently monitored at the same central corneal area during the preoperative phase, as well as in the early (within 1 year) and late (after 3 years) postoperative phases. The images from these phases were categorized into 3 groups: typical guttae, atypical guttae, and no guttae. Exposures: Cultured CEC transplant therapy. Main Outcomes: Proportion of guttae in the observable area was measured, comparing the early and late postoperative phases for each group. Results: The mean age of the patients at the time of surgery was 69 years (range, 49-79 years). All 15 eyes exhibited the presence of confluent guttae preoperatively (100%). Among these, 3 of 15 eyes belonged to male patients. The early postoperative phase of guttae morphologies was classified into 3 groups: 5 eyes with typical guttae, 7 with atypical guttae, and 3 with no guttae. The decrease in the number of these guttae was achieved by surgical procedures. The median percentage of guttae in the typical guttae, atypical guttae, and no guttae groups was 41.8%, 44.4%, and 16.2%, respectively, in the early phase, and 42.2%, 38.2%, and 18.8%, respectively, in the late phase. Conclusions and Relevance: The findings demonstrate that in some cases of FECD, guttae can be removed by scraping and polishing abnormal ECM and degenerated CECs, while preserving the Descemet membrane. Furthermore, cultured CEC transplant resulted in no increase in guttae for up to 3 years, providing insights into surgically eliminating guttae.

4.
Invest Ophthalmol Vis Sci ; 65(6): 37, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38935029

RESUMO

Purpose: To investigate the molecular mechanism of pathological keratinization in the chronic phase of ocular surface (OS) diseases. Methods: In this study, a comprehensive gene expression analysis was performed using oligonucleotide microarrays on OS epithelial cells obtained from three patients with pathological keratinization (Stevens-Johnson syndrome [n = 1 patient], ocular cicatricial pemphigoid [n = 1 patient], and anterior staphyloma [n = 1 patient]). The controls were three patients with conjunctivochalasis. The expression in some transcripts was confirmed using quantitative real-time PCR. Results: Compared to the controls, 3118 genes were significantly upregulated by a factor of 2 or more than one-half in the pathological keratinized epithelial cells (analysis of variance P < 0.05). Genes involved in keratinization, lipid metabolism, and oxidoreductase were upregulated, while genes involved in cellular response, as well as known transcription factors (TFs), were downregulated. Those genes were further analyzed with respect to TFs and retinoic acid (RA) through gene ontology analysis and known reports. The expression of TFs MYBL2, FOXM1, and SREBF2, was upregulated, and the TF ELF3 was significantly downregulated. The expression of AKR1B15, RDH12, and CRABP2 (i.e., genes related to RA, which is known to suppress keratinization) was increased more than twentyfold, whereas the expression of genes RARB and RARRES3 was decreased by 1/50. CRABP2, RARB, and RARRES3 expression changes were also confirmed by qRT-PCR. Conclusions: In pathological keratinized ocular surfaces, common transcript changes, including abnormalities in vitamin A metabolism, are involved in the mechanism of pathological keratinization.


Assuntos
Regulação da Expressão Gênica , Reação em Cadeia da Polimerase em Tempo Real , Humanos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Perfilação da Expressão Gênica , Penfigoide Mucomembranoso Benigno/genética , Penfigoide Mucomembranoso Benigno/metabolismo , Queratinas/metabolismo , Queratinas/genética , Doenças da Córnea/genética , Doenças da Córnea/metabolismo , Doenças da Córnea/patologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Doenças da Túnica Conjuntiva/genética , Doenças da Túnica Conjuntiva/metabolismo , Doenças da Túnica Conjuntiva/patologia
5.
Am J Ophthalmol ; 267: 50-60, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38795750

RESUMO

PURPOSE: To investigate the incidence and prognostic factors of ocular sequelae in Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) cases arising between 2016 and 2018 in Japan, and compare the findings with those presented in the previous 2005-2007 survey. DESIGN: Retrospective, national trend survey. METHODS: Dermatologic case report forms (CRFs) (d-CRFs) were sent to 257 institutions that treated at least 1 SJS/TEN case, and 508 CRFs were collected from 160 institutions. Ophthalmologic CRFs (o-CRFs) regarding patient demographic data, onset date, ocular findings (first appearance, day of worst severity, and final follow-up), topical treatment (betamethasone), outcome (survival or death), and ocular sequelae (visual disturbance, eye dryness) were sent to the ophthalmologists in those 160 institutions. The results of this survey were then compared with that of the previous 2005-2007 survey. RESULTS: A total of 240 cases (SJS/TEN: 132/108) were included. The incidence of ocular sequelae incidence was 14.0%, a significant decrease from the 39.2% in the previous survey (SJS/TEN: 87/48). In 197 (82.1%) of the cases, systemic treatment was initiated within 3 days after admission, an increase compared to the previous survey (ie, treatment initiated in 82 [60.7%] of 135 cases). Of the 85 cases with an Acute Ocular Severity Score of 2 and 3, 62 (72.9%) received corticosteroid pulse therapy and 73 (85.9%) received 0.1% betamethasone therapy; an increase compared to the 60.0% and 70.8%, respectively, in the previous survey. Ocular-sequelae-associated risk factors included Acute Ocular Severity Score (P < .001) and specific year in the survey (P < .001). CONCLUSIONS: The ophthalmologic prognosis of SJS/TEN has dramatically improved via early diagnosis, rapid assessment of acute ocular severity, and early treatment.

7.
Am J Ophthalmol ; 262: 1-9, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38307212

RESUMO

PURPOSE: To examine corneal graft survival via corneal endothelial cell density (ECD) and corneal endothelial cell loss (ECL) at 5 years post-transplantation in the eyes of patients with and without a history of undergoing glaucoma surgery according to the maturity of the donor corneal endothelial cells. DESIGN: Prospective cohort study. METHODS: This prospective cohort study included 17 patients with glaucoma and 51 patients without glaucoma who underwent Descemet's stripping automated endothelial keratoplasty or penetrating keratoplasty at the Baptist Eye Institute, Kyoto, Japan, between October 2014 and October 2016. Human corneal endothelial cells were cultured from residual peripheral donor cornea tissue, and the maturity of the cells was evaluated by cell surface markers (ie, CD166+, CD44-/dull, CD24-, and CD105-) using fluorescence-activated cell sorting. Kaplan-Meier analysis or the chi-square test was used to assess the rate of successful corneal graft survival post-transplantation. RESULTS: At 36 months postoperatively, the mean ECD and ECL in the glaucoma-bleb eyes were 1197 ± 352 cells/mm2 and 55.5% ± 13.9% in the high-maturity group and 853 ± 430 cells/mm2 and 67.7% ± 18.1% in the low-maturity group, respectively. Kaplan-Meier analysis revealed that at 5 years postoperatively, the overall rate of survival was 45%, that is, 100% in the high-maturity group and 25% in the low-maturity group (P < .05). CONCLUSIONS: The findings in this prospective cohort study revealed that the use of donor corneal grafts containing mature-differentiated corneal endothelial cells could maintain the survival of the transplanted graft for a long-term period, even in patients with a history of undergoing glaucoma surgery.


Assuntos
Endotélio Corneano , Glaucoma , Sobrevivência de Enxerto , Pressão Intraocular , Doadores de Tecidos , Humanos , Sobrevivência de Enxerto/fisiologia , Estudos Prospectivos , Masculino , Feminino , Endotélio Corneano/patologia , Idoso , Contagem de Células , Pessoa de Meia-Idade , Pressão Intraocular/fisiologia , Glaucoma/cirurgia , Glaucoma/fisiopatologia , Perda de Células Endoteliais da Córnea/diagnóstico , Ceratoplastia Penetrante , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Seguimentos , Citometria de Fluxo , Idoso de 80 Anos ou mais , Acuidade Visual/fisiologia
8.
JAMA Ophthalmol ; 142(1): 39-47, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38127333

RESUMO

Importance: Pediatric blepharokeratoconjunctivitis (PBKC) is a chronic, sight-threatening inflammatory ocular surface disease. Due to the lack of unified terminology and diagnostic criteria, nonspecific symptoms and signs, and the challenge of differentiation from similar ocular surface disorders, PBKC may be frequently unrecognized or diagnosed late. Objective: To establish a consensus on the nomenclature, definition, and diagnostic criteria of PBKC. Design, Setting, and Participants: This quality improvement study used expert panel and agreement applying the non-RAND modified Delphi method and open discussions to identify unified nomenclature, definition, and definitive diagnostic criteria for PBKC. The study was conducted between September 1, 2021, and August 14, 2022. Consensus activities were carried out through electronic surveys via email and online virtual meetings. Results: Of 16 expert international panelists (pediatric ophthalmologists or cornea and external diseases specialists) chosen by specific inclusion criteria, including their contribution to scientific leadership and research in PBKC, 14 (87.5%) participated in the consensus. The name proposed was "pediatric blepharokeratoconjunctivitis," and the agreed-on definition was "Pediatric blepharokeratoconjunctivitis is a frequently underdiagnosed, sight-threatening, chronic, and recurrent inflammatory eyelid margin disease associated with ocular surface involvement affecting children and adolescents. Its clinical spectrum includes chronic blepharitis, meibomitis, conjunctivitis, and corneal involvement ranging from superficial punctate keratitis to corneal infiltrates with vascularization and scarring." The diagnostic criteria included 1 or more suggestive symptoms accompanied by clinical signs from 3 anatomical regions: the eyelid margin, conjunctiva, and cornea. For PBKC suspect, the same criteria were included except for corneal involvement. Conclusions and Relevance: The agreements on the name, definition, and proposed diagnostic criteria of PBKC may help ophthalmologists avoid diagnostic confusion and recognize the disease early to establish adequate therapy and avoid sight-threatening complications. The diagnostic criteria rely on published evidence, analysis of simulated clinical cases, and the expert panel's clinical experience, requiring further validation with real patient data analysis.


Assuntos
Blefarite , Ceratoconjuntivite , Adolescente , Criança , Humanos , Ceratoconjuntivite/diagnóstico , Ceratoconjuntivite/complicações , Ceratoconjuntivite/tratamento farmacológico , Blefarite/diagnóstico , Blefarite/tratamento farmacológico , Pálpebras , Túnica Conjuntiva , Córnea , Doença Crônica
9.
Diagnostics (Basel) ; 14(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38201312

RESUMO

Punctal occlusion (PO) is considered to improve both tear-film instability and increased friction during blinking and may consequently affect blinks. The purpose of this study was to investigate the effect of PO on blinks. This study involved 16 eyes of 16 severe aqueous deficient dry eye (ADDE) patients (mean age: 65.7 years). In all eyes, tear meniscus radius (TMR), spread grade (SG) of the tear-film lipid layer (i.e., SG 1-5: 1 being the best), fluorescein break-up time (FBUT), corneal epithelial damage score (CED), conjunctival epithelial damage score, corneal filament (CF) grade, lid-wiper epitheliopathy (LWE) grade, and superior limbic keratoconjunctivitis (SLK) grade were evaluated at before and at more than 1-month after PO. Moreover, using a custom-made high-speed blink analyzer, palpebral aperture height, blink rate, upper-eyelid closing-phase amplitude/duration/maximum velocity, and upper-eyelid opening-phase amplitude/duration/maximum velocity were measured at the same time point. After PO, TMR, SG, FBUT, CED, and the CF, LWE, and SLK grades were significantly improved, and upper-eyelid opening/closing-phase amplitude and maximum velocity significantly increased (all p < 0.04). The findings of this study suggest that PO improves ocular surface lubrication and that blink-related parameters can reflect the friction that occurs during blinking in eyes with severe ADDE.

10.
Diagnostics (Basel) ; 14(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38201400

RESUMO

In this study, we evaluated the effectiveness of a single-dose oral pilocarpine administration on tear film (TF), as well as dry eye and dry mouth symptoms, in 53 eyes of 27 Sjögren syndrome (SS) patients who were experiencing dry mouth. To evaluate the changes in tear volume, a digital video-meniscometer was used to measure the radius of the lower central tear meniscus curvature (R, mm) of each eye at prior to the administration of 5 mg oral pilocarpine, and at 15 (R:(15)), 30 (R:(30)), and 60 (R:(60)) minutes after administration. The fluorescein breakup time (FBUT, seconds) and ocular and oral dryness symptoms were evaluated before and at 60 min after administration using a visual analogue scale (VAS, mm). A significant increase in R was observed at 15 and 30 min after administration compared to that at prior to administration. FBUT showed significant improvement at 60 min after administration, and the VAS score for ocular and oral dryness symptoms was found to have decreased significantly at 60 min after administration. A single-dose administration of 5 mg oral pilocarpine had a beneficial effect on TF, as well as on ocular and oral dryness symptoms, in patients with SS.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA