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1.
FASEB J ; 36(7): e22397, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35661268

RESUMO

Corneal endothelial cell (CEC) dysfunction causes corneal edema and severe visual impairment that require transplantation to restore vision. To address the unmet need of organ shortage, descemetorhexis without endothelial keratoplasty has been specifically employed to treat early stage Fuchs endothelial corneal dystrophy, which is pathophysiologically related to oxidative stress and exhibits centrally located corneal guttae. After stripping off central Descemet's membrane, rho-associated protein kinase (ROCK) inhibitor has been found to facilitate CEC migration, an energy-demanding task, thereby achieving wound closure. However, the correlation between ROCK inhibition and the change in bioenergetic status of CECs remained to be elucidated. Through transcriptomic profiling, we found that the inhibition of ROCK activity by the selective inhibitor, ripasudil or Y27632, promoted enrichment of oxidative phosphorylation (OXPHOS) gene set in bovine CECs (BCECs). Functional analysis revealed that ripasudil, a clinically approved anti-glaucoma agent, enhanced mitochondrial respiration, increased spare respiratory capacity, and induced overexpression of electron transport chain components through upregulation of AMP-activated protein kinase (AMPK) pathway. Accelerated BCEC migration and in vitro wound healing by ripasudil were diminished by OXPHOS and AMPK inhibition, but not by glycolysis inhibition. Correspondingly, lamellipodial protrusion and actin assembly that were augmented by ripasudil became reduced with additional OXPHOS or AMPK inhibition. These results indicate that ROCK inhibition induces metabolic reprogramming toward OXPHOS to support migration of CECs.


Assuntos
Endotélio Corneano , Distrofia Endotelial de Fuchs , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Bovinos , Células Endoteliais/metabolismo , Endotélio Corneano/metabolismo , Distrofia Endotelial de Fuchs/genética , Distrofia Endotelial de Fuchs/metabolismo , Distrofia Endotelial de Fuchs/cirurgia , Fosforilação Oxidativa , Quinases Associadas a rho/metabolismo
2.
J Therm Biol ; 115: 103617, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37352595

RESUMO

Intraoperatively acquired pressure injuries (IAPIs) occur frequently among patients who undergo surgical procedures that last longer than 3 h. Several studies indicated that heat shock proteins (HSPs) play an important role in the protection of stress-induced damages in skin tissues. Hence, the aim of this study was to investigate the potential preventive effect of thermal preconditioning (TPC) on IAPIs in surgical patients and rats and to identify the differentially expressed HSP genes in response to the above treatment. TPC was performed on one group of hairless rats before the model of pressure injuries was established. Subsequently, the size of skin lesions was measured and the expression levels of mRNA and protein of HSPs of the pressured skin were detected by real-time polymerase chain reaction (RT-PCR), western blot, and immunohistochemical staining. For human studies, 118 surgical patients were randomly divided into the TPC group (n = 59) and the control group (n = 59), respectively. The temperature and pressure of sacral skin, as well as the incidence of pressure injury (PI) were detected and compared. In animal studies, TPC significantly reduced both the size and incidence of PI in rats on the second, third and fourth days post treatment. In addition, the expression levels of both mRNA and protein of HSP27 were increased in the TPC group, compared with the control group. Immunohistochemical staining showed that HSP27 was distributed in various types of dermal cells and increased in basal cells. In human studies, a significant reduction (75%) of IAPIs was observed among the patients in the TPC group. TPC can reduce the incidence of PI in rats and humans, and the upregulation of HSP27 may play an important role in this biological progress. Further studies are warranted to explore the molecular mechanism of the preventive effect in PI mediated by HSP27.


Assuntos
Úlcera por Pressão , Ratos , Humanos , Animais , Úlcera por Pressão/prevenção & controle , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/metabolismo , Incidência , RNA Mensageiro/genética , Proteínas de Choque Térmico HSP70/genética
3.
Acta Cardiol Sin ; 38(5): 612-622, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36176366

RESUMO

Background: Home blood pressure telemonitoring (BPT) has been shown to improve blood pressure control. A community-based BPT program (the Health+ program) was launched in 2015 in an urban area around a medical center. Objectives: To examine the impact of the BPT program on the use of medical resources. Methods: We conducted a retrospective propensity-score (PS)-matched observational cohort study using the National Health Insurance Research Database (NHIRD) 2013-2016 in Taiwan. A total of 9,546 adults with a high risk of cardiovascular disease participated in the integrated BPT program, and 19,082 PS-matched controls were identified from the NHIRD. The primary and secondary outcome measures were changes in 1-year emergency department visit rate, hospitalization rate, duration of hospital stay, and healthcare costs. Results: The number of emergency department visits in the Health+ group significantly reduced (0.8 to 0.6 per year vs. 0.8 to 0.9 per year, p < 0.0001) along with a significant decrease in hospitalization rate (43.7% to 21.3% vs. 42.7% to 35.3%, p < 0.001). The duration of hospital stay was also lower in the Health+ group (4.3 to 3.3 days vs. 5.3 to 6.5 days, p < 0.0001). The annual healthcare costs decreased more in the Health+ group (USD 1642 to 1169 vs. 1466 to 1393 per year, p < 0.001), compared with the controls. Subgroup analysis of the Health+ group revealed that the improvements in outcomes were significantly greater among those who were younger and had fewer comorbidities, especially without diabetes or hypertension. Conclusions: A community-based integrated BPT program may improve patients' health outcomes and reduce healthcare costs.

4.
J Formos Med Assoc ; 120(1 Pt 1): 137-144, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32223997

RESUMO

PURPOSE: To establish an appropriate clinical protocol for early photoscreening in 12-to-24-month-old children at pediatric well-baby clinics. METHODS: This prospective study included a total of 277 children aged 12-24 months who visited a pediatric well-baby clinic. All participants underwent: 1) inquiry of medical history; 2) photoscreening with PlusoptiX A12; and 3) comprehensive ophthalmologic examinations. The optimal referral cut-off point for PlusoptiX was determined by receiver operating characteristic analyses. A high-risk subgroup was defined as having a birth weight <3000 g or a history of major systemic diseases, based on the results of multivariable risk factor analysis from children's medical history. A strategy of selective photoscreening focusing on the high-risk subgroup was evaluated. The main outcome measures included sensitivity, specificity, and positive and negative predictive values. RESULTS: The prevalence of amblyopia risk factors in our study population was 12.3%. A total of 172 children (62.1%) were assigned to the high-risk subgroup. Compared with the nonselective photoscreening of all 277 children, selective photoscreening of the high-risk children yielded a higher positive predictive value (59.6% vs. 46.7%, p = 0.001) while showing no difference in sensitivity (82.3% vs. 85.3%, p = 0.32), specificity (92.2% vs, 86.4%, p = 0.05), and negative predictive value (97.4% vs. 97.6%, p = 0.50). CONCLUSION: At pediatric well-baby clinics, selective photoscreening among 12-to-24-month-old children with a birth weight <3000 g or a history of major systemic diseases helped reducing the number of children need to be screened and conserving medical resources yet identifying children at risk for timely eye care.


Assuntos
Ambliopia , Seleção Visual , Ambliopia/diagnóstico , Ambliopia/epidemiologia , Pré-Escolar , Humanos , Lactente , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco
5.
J Formos Med Assoc ; 120(7): 1478-1484, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33243538

RESUMO

BACKGROUND/PURPOSE: To investigate the characteristics of subjective symptoms and objective parameters among young patients with dry eye disease (DED) and compare them with those of older patients. METHODS: We retrospectively enrolled 675 patients with DED who were divided into three age groups (20-41 years [younger], 41-60 years [middle], and >60 years [older]) (n = 143, 304, and 228, respectively). Subjective symptoms were evaluated using Standardized Patient Evaluation of Eye Dryness (SPEED) and Ocular Surface Disease Index (OSDI) questionnaires. Aqueous tear secretion was evaluated with the Schirmer test II. The number of expressible meibomian glands was evaluated with a slit-lamp-aided standardized evaluator. Lipid layer thickness (LLT), blink/incomplete blink rates and meibography were measured with the LipiView® II interferometer. The extent of the meibomian gland dropout was graded using a meiboscale. RESULTS: The younger age group had higher subjective symptom severity, as reflected by higher SPEED (p < 0.001) and OSDI scores (p = 0.051). The SPEED scores negatively correlated with LLT in all patients (r = -0.136, p < 0.001). Younger patients also had thinner average LLT (p < 0.001), lower meiboscale (p < 0.001) and a higher number of expressible meibomian glands (p < 0.001). Additionally, they had significantly more total blinks (p < 0.001), incomplete blinks (p < 0.001), and incomplete blink rate (p = 0.006). CONCLUSION: Manifestations of DED vary with age. In our cohort, younger age patients had more symptoms and blinks, which may have resulted from thinner LLT as the structure and function of the meibomian glands were affected less than in middle and older age patients.


Assuntos
Síndromes do Olho Seco , Lágrimas , Adulto , Idoso , Humanos , Lipídeos , Glândulas Tarsais , Estudos Retrospectivos , Adulto Jovem
6.
Int J Mol Sci ; 21(6)2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32245267

RESUMO

As emerging evidence suggesting neurodegenerative diseases and metabolic diseases have common pathogenesis, we hypothesized that the neurite outgrowth-controlling collapsin response mediator protein 2 (CRMP2) was involved in energy homeostasis. Therefore, putative roles of CRMP2 in adipocyte differentiation (adipogenesis) and lipid metabolism were explored and addressed in this study. CRMP2 expression profiles were in vitro and in vivo characterized during adipogenic process of 3T3-L1 pre-adipocytes and diet-induced obese (DIO) mice, respectively. Effects of CRMP2 on lipid metabolism and deposits were also analyzed. Our data revealed that CRMP2 expression pattern was coupled with adipogenic stages. CRMP2 overexpression inhibited cell proliferation at MCE phase, and significantly reduced lipid contents by down-regulating adipogenesis-driving transcription factors and lipid-synthesizing enzymes. Interestingly, GLUT4 translocation and the lipid droplets fusion were disturbed in CRMP2-silencing cells by affecting actin polymerization. Moreover, adipose CRMP2 was significantly increased in DIO mice, indicating CRMP2 is associated with obesity. Accordingly, CRMP2 exerts multiple functions in adipogenesis and lipid deposits through mediating cell proliferation, glucose/lipid metabolism and cytoskeleton dynamics. The present study identifies novel roles of CRMP2 in mediating adipogenesis and possible implication in metabolic disorders, as well as provides molecular evidence supporting the link of pathogenesis between neurodegenerative diseases and metabolic abnormalities.


Assuntos
Adipócitos/metabolismo , Citoesqueleto/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metabolismo dos Lipídeos/genética , Proteínas do Tecido Nervoso/metabolismo , Obesidade/metabolismo , Células 3T3-L1 , Actinas/metabolismo , Adipócitos/citologia , Adipogenia/genética , Animais , Proliferação de Células/genética , Dieta Hiperlipídica , Técnicas de Silenciamento de Genes , Inativação Gênica , Glucose/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/genética , Obesidade/genética , RNA Interferente Pequeno , Transdução de Sinais/genética , Regulação para Cima
7.
J Neurosci ; 36(30): 7911-24, 2016 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-27466336

RESUMO

UNLABELLED: Neurotransmitter release requires the formation of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes by SNARE proteins syntaxin-1 (Stx1), synaptosomal-associated protein 25 (SNAP-25), and synaptobrevin-2 (Syb2). In mammalian systems, loss of SNAP-25 or Syb2 severely impairs neurotransmitter release; however, complete loss of function studies for Stx1 have been elusive due to the functional redundancy between Stx1 isoforms Stx1A and Stx1B and the embryonic lethality of Stx1A/1B double knock-out (DKO) mice. Here, we studied the roles of Stx1 in neuronal maintenance and neurotransmitter release in mice with constitutive or conditional deletion of Stx1B on an Stx1A-null background. Both constitutive and postnatal loss of Stx1 severely compromised neuronal viability in vivo and in vitro, indicating an obligatory role of Stx1 for maintenance of developing and mature neurons. Loss of Munc18-1, a high-affinity binding partner of Stx1, also showed severely impaired neuronal viability, but with a slower time course compared with Stx1A/1B DKO neurons, and exogenous Stx1A or Stx1B expression significantly delayed Munc18-1-dependent lethality. In addition, loss of Stx1 completely abolished fusion-competent vesicles and severely impaired vesicle docking, demonstrating its essential roles in neurotransmission. Putative partial SNARE complex assembly with the SNARE motif mutant Stx1A(AV) (A240V, V244A) was not sufficient to rescue neurotransmission despite full recovery of vesicle docking and neuronal survival. Together, these data suggest that Stx1 has independent functions in neuronal maintenance and neurotransmitter release and complete SNARE complex formation is required for vesicle fusion and priming, whereas partial SNARE complex formation is sufficient for vesicle docking and neuronal maintenance. SIGNIFICANCE STATEMENT: Syntaxin-1 (Stx1) is a component of the synaptic vesicle soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex and is essential for neurotransmission. We present the first detailed loss-of-function characterization of the two Stx1 isoforms in central mammalian neurons. We show that Stx1 is fundamental for maintenance of developing and mature neurons and also for vesicle docking and neurotransmission. We also demonstrate that neuronal maintenance and neurotransmitter release are regulated by Stx1 through independent functions. Furthermore, we show that SNARE complex formation is required for vesicle fusion, whereas partial SNARE complex formation is sufficient for vesicle docking and neuronal maintenance. Therefore, our work provides insights into differential functions of Stx1 in neuronal maintenance and neurotransmission, with the latter explored further into its functions in vesicle docking and fusion.


Assuntos
Fusão de Membrana/fisiologia , Neurônios/fisiologia , Terminações Pré-Sinápticas/fisiologia , Transmissão Sináptica/fisiologia , Vesículas Sinápticas/fisiologia , Sintaxina 1/metabolismo , Animais , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Feminino , Hipocampo/citologia , Hipocampo/fisiologia , Masculino , Camundongos , Neurogênese/fisiologia , Neurônios/citologia , Terminações Pré-Sinápticas/ultraestrutura , Vesículas Sinápticas/ultraestrutura
8.
Mediators Inflamm ; 2017: 9601349, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29434444

RESUMO

PURPOSE: This study aimed to determine the effect and roles of microRNA (miRNA, miR) treatment in experimental autoimmune anterior uveitis (EAAU). MATERIALS AND METHODS: Uveitis was induced in Lewis rats by simultaneous injections of bovine melanin-associated antigen into the hind footpad and the intraperitoneal cavity. The animals were injected intravitreally with low-dose (0.5 µg) or high-dose (1.5 µg) miR-146a. The clinical scores, leukocyte count in the aqueous humor, and histology were assessed. Cytokine changes were evaluated by relative mRNA expression and enzyme-linked immunosorbent assay (ELISA). The expression of nuclear factor kappa B (NF-κB) was assessed by immunofluorescence and Western blotting. Evaluation of the DNA-binding activity of NF-κB was performed by electrophoretic mobility shift assay (EMSA). RESULTS: Treatment with miR-146a significantly attenuated clinical scores and leukocyte infiltration in a dose-dependent manner, a result that was compatible with histological findings. Following miR-146a injections, downregulation of interleukin- (IL-) 1ß, IL-6, and IL-12 and interferon- (IFN-) γ and upregulation of IL-10 and IL-17 were noted. The decreased NF-κB expression on immunofluorescence and Western blotting and reduced DNA-binding activity on EMSA were demonstrated following miR-146a treatment. CONCLUSIONS: miR-146a effectively reduced intraocular inflammation in EAAU through the inhibition of NF-κB. miR-146a might be a new treatment choice for uveitis.


Assuntos
Doenças Autoimunes/tratamento farmacológico , MicroRNAs/uso terapêutico , Uveíte Anterior/tratamento farmacológico , Animais , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Citocinas/análise , Citocinas/genética , DNA/metabolismo , NF-kappa B/análise , NF-kappa B/metabolismo , Polimorfismo de Nucleotídeo Único , Ratos , Ratos Endogâmicos Lew , Uveíte Anterior/imunologia , Uveíte Anterior/patologia
9.
J Formos Med Assoc ; 116(7): 554-559, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27817990

RESUMO

BACKGROUND/PURPOSE: To evaluate meibomian gland dysfunction (MGD) by infrared thermography. METHODS: An observational study was conducted at the Department of Ophthalmology, Far Eastern Memorial Hospital, New Taipei City, Taiwan. Participants included 89 MGD patients (30 in Grade 1, 49 in Grade 2, and 10 in Grade 3) and 65 controls. The close-eye thermographic images of the eyelid were obtained noninvasively by infrared thermography. Temperatures at 8 regions of interest (ROIs) of the eyelid margin and a reference temperature at the center of the upper eyelid were measured. The temperature ratio was defined as the temperature of ROI divided by the reference temperature. RESULTS: Eyelid margin temperature measured by infrared thermography increased from temporal side (ROI 1) to the nasal side (ROI 8) of the eye in both MGD patients and control groups. The temperature ratios were significantly higher in MGD participants than in controls, especially at ROI 8. CONCLUSION: The eyelid margin temperature measured by infrared thermography was higher in MGD participants. Further development of this infrared thermography system may become a rapid and non-invasive tool for MGD screening.


Assuntos
Doenças Palpebrais/diagnóstico , Glândulas Tarsais/fisiopatologia , Termografia/métodos , Adulto , Idoso , Doenças Palpebrais/fisiopatologia , Feminino , Humanos , Raios Infravermelhos , Masculino , Pessoa de Meia-Idade , Temperatura
10.
J Formos Med Assoc ; 116(3): 177-184, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27421176

RESUMO

BACKGROUND/PURPOSE: This study aims to quantify and identify risk factors for intraocular lens (IOL) tilt and decentration early after surgery using Scheimpflug imaging. METHODS: We prospectively included 268 eyes of 253 patients who underwent uneventful cataract surgery and one-piece IOL implantation using a superior or temporal approach. Scheimpflug imaging was used to evaluate the tilt and decentration of IOLs at 1 week, 1 month, and 3 months postoperatively. Differences in IOL tilt and decentration between the approaches were examined. Correlations of age and axial length with the magnitudes of IOL decentration and tilt were also examined. RESULTS: In total, 139 right and 129 left eyes were included. IOL displacement averaged 150 µm upward and 150 µm to the nasal side of the pupil. Over 50% of the eyes were tilted upward and approximately 90% to the temporal side. The surgical approach was significantly associated with horizontal decentration in both eyes, but significantly associated with only vertical decentration in the right eye 1 week postoperatively. In the left eyes, IOLs were shifted to the nasal side in 57.1% and 36.8% of the eyes that received the temporal and the superior approach, respectively, compared with 75.8% and 50% in the right eyes. The differences were significant only at 1-week follow-up (p = 0.035 and p = 0.003, respectively). Age or axial length was not associated with IOL tilt or decentration in either eye. CONCLUSION: Scheimpflug imaging can be used as a quantitative tool to evaluate IOL position. The incision site affected the IOL position, this finding was significant at 1 week postoperatively only.


Assuntos
Migração do Implante de Lente Intraocular/diagnóstico por imagem , Lentes Intraoculares , Facoemulsificação/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fotografação , Complicações Pós-Operatórias/diagnóstico por imagem , Estudos Prospectivos , Análise de Regressão , Fatores de Risco , Taiwan , Acuidade Visual/fisiologia
11.
Int Ophthalmol ; 37(3): 673-681, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27561748

RESUMO

The aim of this study was to compare the refractive errors after uneventful phacoemulsification and intraocular lens implantation in the cases of vitrectomized eyes and non-vitrectomized eyes. Vitrectomized eyes were divided into 2 groups: vitrectomy alone as Group 1, vitrectomy with gas tamponade as Group 2. Normal-controlled eyes were categorized as Group 3. Intraocular lens (IOL) power calculation and the measurements of axial length (AL) and keratometric value (K) were performed using the IOLMaster and the Haigis and SRK/T formula as subgroup A and B. The measurements of AL, K, and IOL power calculation were also performed by the applanation ultrasound and the SRK/T formula as comparison subgroup C. The mean numeric error (MNE) and median absolute error (MedAE) were compared between Groups and subgroups. The MedAE was not significantly different in Group 1A, 2A, and 3A, respectively (p > 0.05). The MNE was significantly different in Group 1A, 2A, and 3A (p = 0.04). Post hoc test showed an insignificant difference between Group 1A and 3A (p = 0.36), but significantly a higher MNE in Group 2A than that in Group 3A (p = 0.03). A significantly longer AL was noted in Group 1B and 2B, comparing with Group 1C and 2C (p < 0.01). Refractive outcomes after phacoemulsification sequential to vitrectomy alone were comparable to those in normal control. Hyperopic shift was found following phacoemulsification sequential to vitrectomy with gas tamponade comparing to normal eyes. A significantly longer AL was found using optical biometry compared to applanation ultrasound in vitrectomized eyes, but not in normal eyes.


Assuntos
Catarata/complicações , Lentes Intraoculares , Facoemulsificação/métodos , Refração Ocular/fisiologia , Erros de Refração/etiologia , Descolamento Retiniano/complicações , Vitrectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Erros de Refração/diagnóstico , Erros de Refração/fisiopatologia , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Testes Visuais , Acuidade Visual
12.
J Neurosci ; 35(21): 8272-90, 2015 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-26019341

RESUMO

Complexins (Cplxs) are small synaptic proteins that cooperate with SNARE-complexes in the control of synaptic vesicle (SV) fusion. Studies involving genetic mutation, knock-down, or knock-out indicated two key functions of Cplx that are not mutually exclusive but cannot easily be reconciled, one in facilitating SV fusion, and one in "clamping" SVs to prevent premature fusion. Most studies on the role of Cplxs in mammalian synapse function have relied on cultured neurons, heterologous expression systems, or membrane fusion assays in vitro, whereas little is known about the function of Cplxs in native synapses. We therefore studied consequences of genetic ablation of Cplx1 in the mouse calyx of Held synapse, and discovered a developmentally exacerbating phenotype of reduced spontaneous and evoked transmission but excessive asynchronous release after stimulation, compatible with combined facilitating and clamping functions of Cplx1. Because action potential waveforms, Ca(2+) influx, readily releasable SV pool size, and quantal size were unaltered, the reduced synaptic strength in the absence of Cplx1 is most likely a consequence of a decreased release probability, which is caused, in part, by less tight coupling between Ca(2+) channels and docked SV. We found further that the excessive asynchronous release in Cplx1-deficient calyces triggered aberrant action potentials in their target neurons, and slowed-down the recovery of EPSCs after depleting stimuli. The augmented asynchronous release had a delayed onset and lasted hundreds of milliseconds, indicating that it predominantly represents fusion of newly recruited SVs, which remain unstable and prone to premature fusion in the absence of Cplx1.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/deficiência , Tronco Encefálico/metabolismo , Proteínas do Tecido Nervoso/deficiência , Sinapses/metabolismo , Vesículas Sinápticas/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/biossíntese , Animais , Tronco Encefálico/citologia , Adesão Celular/fisiologia , Exocitose/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/biossíntese
13.
Am J Pathol ; 185(8): 2158-67, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26216284

RESUMO

Ex vivo culture or regeneration of corneal endothelial cells often is subjected to gradual endothelial-mesenchymal transition and loss of function. Here, we found that during ex vivo culture, bovine corneal endothelial cells underwent endothelial-mesenchymal transition and had an up-regulated expression and activity of matrix metalloproteinases. Inhibition of matrix metalloproteinase activity in confluent bovine corneal endothelial cells decreased the level of endothelial-mesenchymal transition regulators: snail and slug. The phosphorylation and degradation of the key Wnt signaling pathway modulator active ß-catenin also were accelerated with the broad-spectrum matrix metalloproteinase inhibitor Marimastat, which may result from decreased N-cadherin shedding and increased intact N-cadherin molecules on the cell membrane. Intracameral injection of Marimastat also suppressed basic fibroblast growth factor-induced endothelial-mesenchymal transition in a rat corneal endothelium cryo-injury model and significantly diminished the corneal edema. Our study indicated that inhibition of matrix metalloproteinase activity can reverse endothelial-mesenchymal transition and preserve the function of corneal endothelial cells both during ex vivo culture and in vivo. This may offer a potential therapeutic target in regenerative medicine for the treatment of corneal endothelial dysfunctions.


Assuntos
Endotélio Corneano/metabolismo , Metaloproteinases da Matriz/metabolismo , Animais , Caderinas/metabolismo , Bovinos , Células Cultivadas , Córnea/efeitos dos fármacos , Córnea/metabolismo , Córnea/patologia , Endotélio Corneano/efeitos dos fármacos , Endotélio Corneano/patologia , Ácidos Hidroxâmicos/farmacologia , Masculino , Inibidores de Metaloproteinases de Matriz/farmacologia , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos
14.
Exp Eye Res ; 145: 10-16, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26546726

RESUMO

Topical fluoroquinolones are widely used to prevent ocular infections after ophthalmic surgery. However, they have been shown to affect the corneal cell motility, whose mechanism remains indefinite. The purpose of this study was to investigate how fluoroquinolones affect corneal stromal cell motility. Human corneal fibroblasts (HCFs) were incubated in ciprofloxacin (CIP), levofloxacin (LEV), or moxifloxacin (MOX) at 0, 10, 50, and 100 µg/ml for up to 3 days. Effect of CIP, LEV, or MOX on HCF migration was monitored using migration assay. HCF viability was determined by WST-1 assay. Expression of focal adhesion kinase (FAK), paxillin (PXN), and their phosphorylated forms were analyzed by immunoblotting. Binding affinity between FAK and PXN was determined by co-immunoprecipitation. Our results revealed that CIP and MOX, but not LEV, noticeably retarded HCF migration. HCF proliferation was significantly reduced by CIP (38.2%), LEV (29.5%), and MOX (21.3%), respectively (p = 0.002). CIP and MOX suppressed the phosphorylation of PXN at tyrosines (10.2 ± 4.3%, p < 0.001; 11.7 ± 2.4%, p < 0.001, respectively), including tyrosine 118 (33.3 ± 5.2%, p < 0.001; 34.0 ± 4.4%, p < 0.001, respectively). CIP and MOX diminished the binding affinity between FAK and PXN (8.2 ± 1.8%, p < 0.001; 9.0 ± 4.5%, p < 0.001, respectively). Nevertheless, tyrosine dephosphorylation and FAK dissociation of PXN were not found in LEV-treated HCFs. None of these fluoroquinolones affect phosphorylation of FAK-Y397. We conclude that CIP and MOX, but not LEV, might delay corneal fibroblast migration via interfering with recruitment of PXN to focal adhesions and dephosphorylation of PXN at the tyrosines.


Assuntos
Úlcera da Córnea/tratamento farmacológico , Epitélio Corneano/metabolismo , Fluoroquinolonas/administração & dosagem , Proteína-Tirosina Quinases de Adesão Focal/biossíntese , Paxilina/biossíntese , Adulto , Idoso , Antibacterianos/administração & dosagem , Contagem de Células , Movimento Celular/efeitos dos fármacos , Úlcera da Córnea/metabolismo , Úlcera da Córnea/patologia , Epitélio Corneano/efeitos dos fármacos , Epitélio Corneano/patologia , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Proteína-Tirosina Quinases de Adesão Focal/efeitos dos fármacos , Humanos , Immunoblotting , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Paxilina/efeitos dos fármacos , Adulto Jovem
15.
PLoS Comput Biol ; 11(2): e1004002, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25646860

RESUMO

Fundamental response properties of neurons centrally underly the computational capabilities of both individual nerve cells and neural networks. Most studies on neuronal input-output relations have focused on continuous-time inputs such as constant or noisy sinusoidal currents. Yet, most neurons communicate via exchanging action potentials (spikes) at discrete times. Here, we systematically analyze the stationary spiking response to regular spiking inputs and reveal that it is generically non-monotonic. Our theoretical analysis shows that the underlying mechanism relies solely on a combination of the discrete nature of the communication by spikes, the capability of locking output to input spikes and limited resources required for spike processing. Numerical simulations of mathematically idealized and biophysically detailed models, as well as neurophysiological experiments confirm and illustrate our theoretical predictions.


Assuntos
Potenciais de Ação/fisiologia , Modelos Neurológicos , Neurônios/fisiologia , Animais , Células Cultivadas , Simulação por Computador , Técnicas de Patch-Clamp , Ratos , Ratos Wistar , Corpo Trapezoide/citologia
16.
Optom Vis Sci ; 93(1): 12-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26583793

RESUMO

PURPOSE: To determine the effect of cycloplegia on corneal thickness, corneal curvature, anterior chamber depth (ACD), angle-to-angle (ATA) and white-to-white (WTW) distances, and axial length (AL). METHODS: Changes in corneal thickness, corneal curvature, ACD, ATA and WTW distances, and AL with and without cycloplegia were analyzed in 31 eyes of 31 young myopic adults, aged 26.4 ± 3.0 years. Pentacam was used to measure the corneal thickness, corneal volume, and corneal curvatures. Visante optical coherent tomography (OCT) measured corneal thickness, ATA distance, ACD, and pupil size. The AL and WTW distance were measured using IOLMaster. RESULTS: Cycloplegia induced significant flattening of corneal curvatures (p = 0.019, 0.001, and 0.003 for anterior sagittal, posterior tangential, and posterior sagittal curvatures, respectively). The difference in the posterior corneal curvature was greater in corneas with steeper posterior curvatures. Cycloplegia also induced significant deepening of ACD (0.08 ± 0.06, p < 0.001) and widening of both WTW (0.42 ± 0.43, p < 0.001) and ATA (0.08 ± 0.17, p = 0.015) distances. The cycloplegia-related increase in the ATA distance correlated negatively with AL (r = -0.361, p = 0.046), whereas the cycloplegia-related increase in WTW distance correlated weakly with the increase in ACD (r = 0.347, p = 0.056) but not with AL. The AL did not change with cycloplegia. Pentacam measured a slightly thicker cornea than OCT (p = 0.002). Both Pentacam and OCT detected a significant increase in corneal thickness of 4 µm, which could be attributed to reflex tearing, after cycloplegia. CONCLUSIONS: Cycloplegia resulted in deeper ACD, greater ATA distance, and flatter corneal curvatures. Surgeons should be aware of these cycloplegia-related alterations for more accurate phakic/functional intraocular lens selection and better refraction results.


Assuntos
Midriáticos/administração & dosagem , Miopia/fisiopatologia , Pupila/efeitos dos fármacos , Pupila/fisiologia , Tropicamida/administração & dosagem , Adulto , Segmento Anterior do Olho/efeitos dos fármacos , Segmento Anterior do Olho/fisiologia , Biometria/métodos , Corpo Ciliar/efeitos dos fármacos , Corpo Ciliar/fisiologia , Córnea/fisiopatologia , Topografia da Córnea , Feminino , Humanos , Masculino , Músculo Liso/fisiologia , Tomografia de Coerência Óptica , Adulto Jovem
17.
Mediators Inflamm ; 2016: 6586857, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27413255

RESUMO

Purpose. The transcellular arginine transportation via cationic amino acid transporter (CAT) is the rate-limiting step in nitric oxide (NO) synthesis, which is crucial in intraocular inflammation. In this study, CAT isoforms and inducible nitric oxide synthase (iNOS) expression was investigated in endotoxin-induced uveitis (EIU). Methods. EIU was induced in Lewis rats by lipopolysaccharide (LPS) injection. In the treatment group, the rats were injected intraperitoneally with the proteasome inhibitor bortezomib before EIU induction. After 24 hours, leukocyte quantification, NO measurement of the aqueous humor, and histopathological examination were evaluated. The expression of CAT isoforms and iNOS was determined by reverse transcription-polymerase chain reaction, western blotting, and immunofluorescence staining. Nuclear factor-kappa B (NF-κB) binding activity was evaluated by electrophoretic mobility shift assay. The mouse macrophage cell line RAW 264.7 was used to validate the in vivo findings. Results. LPS significantly stimulated iNOS, CAT-2A, and CAT-2B mRNA and protein expression but did not affect CAT-1 in EIU rats and RAW 264.7 cells. Bortezomib attenuated inflammation and inhibited iNOS, CAT-2A, and CAT-2B expression through NF-κB inhibition. Conclusions. CAT-2 and iNOS, but not CAT-1, are specifically involved in EIU. NF-κB is essential in the induction of CAT-2 and iNOS in EIU.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Endotoxinas/toxicidade , Uveíte/induzido quimicamente , Uveíte/metabolismo , Sistemas de Transporte de Aminoácidos Básicos/genética , Animais , Western Blotting , Transportador 1 de Aminoácidos Catiônicos/genética , Transportador 1 de Aminoácidos Catiônicos/metabolismo , Transportador 2 de Aminoácidos Catiônicos/genética , Transportador 2 de Aminoácidos Catiônicos/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Ensaio de Imunoadsorção Enzimática , Masculino , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Exp Eye Res ; 131: 69-76, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25543054

RESUMO

This study investigated the protective effects of the administration of steroids on optic nerves (ON) and retinal ganglion cells (RGCs) in a rodent model of non-arteritic anterior ischemic optic neuropathy (rAION). We induced rAION using rose bengal and argon laser irradiation in a photodynamic procedure on the optic discs of rats. The treated groups received methylprednisolone (MP) via peritoneal injection for 2 weeks. The control group received intraperitoneal injections of phosphate-buffered saline (PBS) post-rAION. At the 4th week post-infarct, MP treatments significantly rescued the RGCs (mm(2)) in the central retinas (1920 ± 210, p < 0.001) and mid-peripheral retinas (950 ± 240, respectively, p = 0.018) compared with those of the PBS-treated rats (central: 900 ± 210 and mid-peripheral: 440 ± 180). Functional assessment with flash visual-evoked potentials demonstrated that P1 latency (ms) was shortened in the MP group compared to the PBS group (108 ± 14 and 147 ± 9, respectively, p < 0.001). In addition, the P1 amplitude (uV) was enhanced in the MP group compared to the PBS group (55 ± 12 and 41 ± 13, respectively, p < 0.05). TUNEL assays showed a decrease in the number of apoptotic cells in the RGC layers of MP-treated retinas compared to the PBS-treated group (p < 0.05). ED1 positive cells (/HPF) were significantly decreased in the ONs of the MP group compared to the PBS group (p < 0.001). In conclusion, systemic administration of MP had neuroprotective effects on RGC survival and ON function in the rAION animal model.


Assuntos
Hemissuccinato de Metilprednisolona/uso terapêutico , Neuropatia Óptica Isquêmica/tratamento farmacológico , Animais , Modelos Animais de Doenças , Potenciais Evocados Visuais/efeitos dos fármacos , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Injeções Intraperitoneais , Masculino , Hemissuccinato de Metilprednisolona/administração & dosagem , Nervo Óptico/efeitos dos fármacos , Nervo Óptico/patologia , Neuropatia Óptica Isquêmica/patologia , Neuropatia Óptica Isquêmica/fisiopatologia , Ratos , Ratos Wistar , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/patologia
19.
J Refract Surg ; 31(2): 82-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25735040

RESUMO

PURPOSE: To identify factors associated with surgically induced astigmatism (SIA) following phacoemulsification. METHODS: Six hundred five eyes underwent phacoemulsification with a 2.2-mm (the 2.2-mm group, n = 248) or 2.75-mm (the 2.75-mm group, n = 357) superior limbal incision. Preoperative axial length, anterior chamber depth, corneal curvature, and intra-ocular pressure were measured. Corneal curvature and intraocular pressure were measured at 1 day, 1 week, and 1, 2, and 3 months postoperatively. SIA, corneal flattening, and torque were calculated using the Alpins method. The effect of preoperative corneal astigmatism meridian on SIA was also examined. Differences in SIA between the 2.2- and 2.75-mm groups were explored, and correlations between SIA and preoperative corneal astigmatism, anterior chamber depth, axial length, age, and intraocular pressure were analyzed. RESULTS: SIA, corneal flattening, and torque were smaller in the 2.2-mm group than in the 2.75-mm group at 1 week (P = .003, .006, and .014, respectively), but not statistically different thereafter. Higher preoperative corneal astigmatism, older age, and shallower anterior chamber depth were associated with greater SIA in both groups. The effect of astigmatism meridian on SIA was more noticeable in the 2.75-mm group. Shorter axial length and lower intraocular pressures were associated with greater SIA in the 2.75-mm group but not in the 2.2-mm group. CONCLUSIONS: Reducing limbal incision width and considering patient age, the meridian and magnitude of corneal astigmatism, anterior chamber depth, axial length, and intraocular pressure, and adjusting the flattening component of SIA input for toric intraocular lens power calculation could potentially improve the astigmatism control in refractive lens surgery.


Assuntos
Astigmatismo/etiologia , Córnea/cirurgia , Complicações Intraoperatórias , Facoemulsificação/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Câmara Anterior/patologia , Comprimento Axial do Olho/patologia , Feminino , Humanos , Masculino , Microcirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Cicatrização
20.
Mediators Inflamm ; 2015: 457835, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26713004

RESUMO

Purpose. This study aimed to determine the dynamic changes of NF-κB-related microRNAs (miRNAs) and cytokines over the course of experimental autoimmune anterior uveitis (EAAU) and elucidate the possible immunopathogenesis. Materials and Methods. Uveitis was induced in Lewis rats using bovine melanin-associated antigen. The inflammatory activity of the anterior chamber was clinically scored, and leukocytes in the aqueous humor were quantified. RNA was extracted from the iris/ciliary bodies and popliteal lymph nodes to reveal the dynamic changes of eight target miRNAs (miR-155-5p, miR-146a-5p, miR-182-5p, miR-183-5p, miR-147b, miR-21-5p, miR-9-3p, and miR-223-3p) and six cytokine mRNAs (IFN-γ, IL-17, IL-12A, IL-1ß, IL-6, and IL-10). In situ hybridization of miRNA and enzyme-linked immunosorbent assay quantification of cytokines were performed to confirm the results. Results. Disease activity and leukocyte quantification were maximum at day 15 after immunization. The profiling of miRNA revealed downregulation of miR-146a-5p, miR-155-5p, miR-223-3p, and miR-147b and upregulation of miR-182-5p, miR-183-5p, and miR-9-3p. Cytokine analysis revealed IFN-γ, IL-17, IL-12A, IL-1ß, and IL-6 overexpression, with IL-10 downregulation. Conclusions. Dynamic changes of miRNAs were observed over the course of EAAU. By initiating NF-κB signaling, the expressions of downstream cytokines and effector cells from the Th17 and Th1 lineages were sequentially activated, contributing to the disease.


Assuntos
Olho/imunologia , Regulação da Expressão Gênica , MicroRNAs/análise , Uveíte Anterior/imunologia , Animais , Humor Aquoso/imunologia , Corpo Ciliar/imunologia , Citocinas/análise , Modelos Animais de Doenças , Iris/imunologia , MicroRNAs/genética , NF-kappa B/fisiologia , Ratos , Ratos Endogâmicos Lew , Transdução de Sinais , Uveíte Anterior/etiologia
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