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2.
Retin Cases Brief Rep ; 16(3): 344-346, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32058354

RESUMEN

BACKGROUND/PURPOSE: To report a case of unilateral choroidal detachment and serous retinal detachment in a patient with a history of untreated sarcoidosis. METHODS: Case report. The patient is a 67-year-old African American man with a history of nontreated sarcoidosis and prostate cancer. His prostate cancer was treated several years earlier with external beam radiation therapy. The patient presented with blurred visual acuity of 20/30 and floaters in the right eye. He was discovered to have several hypopigmented choroidal lesions, 360-degree choroidal detachment, and shallow serous retinal detachment in the right eye. RESULTS: The patient was treated with subtenons kenalog and oral prednisone with subsequent improvement of vision and resolution of choroidal and retinal detachment. CONCLUSION: Ocular sarcoidosis can involve any part of the eye and its adnexal tissues and may cause uveitis, episcleritis, scleritis, eyelid abnormalities, conjunctival granuloma, optic neuropathy, lacrimal gland enlargement, and orbital inflammation. Most patients with ophthalmic sarcoidosis have evidence of systemic involvement at the time of the initial examination and have bilateral ocular presentation. We present here the unique case of a 67-year-old man with unilateral 360-degree choroidal detachment and serous retinal detachment as an ocular presentation of sarcoidosis.


Asunto(s)
Efusiones Coroideas , Neoplasias de la Próstata , Desprendimiento de Retina , Sarcoidosis , Escleritis , Uveítis , Anciano , Humanos , Masculino , Neoplasias de la Próstata/complicaciones , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/etiología , Sarcoidosis/complicaciones , Sarcoidosis/diagnóstico
3.
Retina ; 40(5): 943-950, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-30883531

RESUMEN

PURPOSE: To determine the preoperative characteristics, intraoperative and postoperative complications, and outcomes of eyes with posteriorly inserted vitreous base. METHODS: In this retrospective, observational, consecutive case series at 2 academic centers, 37 patients were studied who had posteriorly inserted vitreous base noted during vitrectomy. Posteriorly inserted vitreous base was defined as the insertion of the posterior hyaloid membrane being located posterior to the vortex veins. Fifteen eyes were analyzed in a histopathologic study of donor eyes to determine the average distance of the ora serrata from the vortex veins as this distance is uncertain. RESULTS: Posteriorly inserted vitreous base was identified during vitrectomy in 31 eyes with rhegmatogenous retinal detachment (84%), 4 with macular hole (11%), 1 with vitreous hemorrhage, and 1 with epiretinal membrane. Adjunctive buckle was used in 24%; 54% had 360° laser. Average number of tears seen preoperatively in those with rhegmatogenous retinal detachment was 3.1. Thirty percent had new breaks identified intraoperatively. Forty-one percent had lattice degeneration; new breaks were found in 40% of eyes with lattice. Thirteen percent of rhegmatogenous retinal detachments developed proliferative vitreoretinopathy. Average distance from the ora serrata to the vortex veins was 7.6 mm. CONCLUSION: Any eye undergoing vitrectomy may have posteriorly inserted vitreous base, but those with a high number of retinal breaks and lattice near the equator may be at highest risk. Redetachment and proliferative vitreoretinopathy still occur despite knowledge of the disorder and adjuvant treatments.


Asunto(s)
Retina/diagnóstico por imagen , Enfermedades de la Retina/cirugía , Agudeza Visual , Vitrectomía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Periodo Intraoperatorio , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Enfermedades de la Retina/diagnóstico , Estudios Retrospectivos
4.
Retina ; 40(9): 1719-1723, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31800459

RESUMEN

PURPOSE: To evaluate alterations in treatment burden and course of exudative age-related macular degeneration in patients who contracted endophthalmitis from intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections. METHODS: Retrospective study at the University of Pittsburgh Medical Center examining frequency of anti-VEGF injections, activity of choroidal neovascularization, and visual acuity before and after endophthalmitis treatment. RESULTS: Twenty-one patients meeting inclusion criteria were identified, of whom 7 (33%) patients did not restart anti-VEGF treatment 12 months after endophthalmitis because of quiescence of exudative age-related macular degeneration without significant visual acuity loss (P > 0.05). Patients who resumed anti-VEGF treatment exhibited 32% and 38% decreases in injection frequency by 12 and 24 months after endophthalmitis, respectively (P < 0.05). On first optical coherence tomography follow-up, 10 patients exhibited quiescence of choroidal neovascularization activity, although there were no measurable changes in macular thickness (P > 0.05). No differences in post-endophthalmitis exudative age-related macular degeneration progression or treatment burden were observed when factoring adjuvant intravitreal steroid therapy, culture results, nor choroidal neovascularization subtypes. CONCLUSION: Endophthalmitis resolution is associated with a decrease in choroidal neovascularization activity and a reduction of anti-VEGF treatment burden in patients with exudative age-related macular degeneration.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neovascularización Coroidal/fisiopatología , Endoftalmitis/tratamiento farmacológico , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Inyecciones Intravítreas/efectos adversos , Degeneración Macular Húmeda/fisiopatología , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Bevacizumab/uso terapéutico , Neovascularización Coroidal/tratamiento farmacológico , Endoftalmitis/etiología , Exudados y Transudados , Infecciones Bacterianas del Ojo/etiología , Femenino , Angiografía con Fluoresceína , Humanos , Masculino , Persona de Mediana Edad , Ranibizumab/uso terapéutico , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Agudeza Visual/fisiología , Degeneración Macular Húmeda/tratamiento farmacológico
5.
J AAPOS ; 23(2): 86.e1-86.e7, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30885809

RESUMEN

PURPOSE: To evaluate the effect of a computer-based training program-Massachusetts Eye & Ear ROP Trainer-on residents' knowledge of retinopathy of prematurity (ROP) management. METHODS: In this prospective, randomized study, ophthalmology residents from nine different training programs consented to participate. Those who completed the study were randomly assigned to either the Trainer or the control group. The ROP Trainer was created using clinical cases encompassing the stages of ROP in digital pictures and videos. It includes sections on screening decisions, examination techniques, and diagnosis, and a reference section with the expert video clips and a searchable image library. Subjects in the control group were asked to study standard print material on ROP. A pre- and post-test, consisting of theoretical and practical (diagnosis) questions, and a post-intervention satisfaction test were administered. Accuracy of ROP diagnosis was assessed. RESULTS: A total of 180 residents agreed to participate, of whom 60 completed the study. Residents in the Trainer group had statistically significant improvements (P = 0.003) in ROP knowledge and diagnostic ability (P = 0.005). Residents randomized to the Trainer group were more satisfied with the training materials than were those in the control group. There was no significant difference in improving knowledge by year of training, sex, or country. Considering all training levels, a statistically significant increase was observed in sensitivity for the diagnosis of preplus or worse, zone I or II, ROP stage, category, and aggressive posterior ROP in the Trainer group. CONCLUSIONS: In this study, the Trainer was shown to significantly improve ROP knowledge and diagnostic skills of residents, regardless of sex, year, of training, or country.


Asunto(s)
Competencia Clínica/normas , Instrucción por Computador/métodos , Internado y Residencia/métodos , Oftalmología/educación , Retinopatía de la Prematuridad/diagnóstico , Retroalimentación , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Massachusetts , Oftalmología/normas , Estudios Prospectivos , Retinopatía de la Prematuridad/terapia
6.
Sci Rep ; 7(1): 7602, 2017 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-28790340

RESUMEN

Verteporfin (VP), a light-activated drug used in photodynamic therapy for the treatment of choroidal neovascular membranes, has also been shown to be an effective inhibitor of malignant cells. Recently, studies have demonstrated that, even without photo-activation, VP may still inhibit certain tumor cell lines, including ovarian cancer, hepatocarcinoma and retinoblastoma, through the inhibition of the YAP-TEAD complex. In this study, we examined the effects of VP without light activation on human glioma cell lines (LN229 and SNB19). Through western blot analysis, we identified that human glioma cells that were exposed to VP without light activation demonstrated a downregulation of YAP-TEAD-associated downstream signaling molecules, including c-myc, axl, CTGF, cyr61 and survivin and upregulation of the tumor growth inhibitor molecule p38 MAPK. In addition, we observed that expression of VEGFA and the pluripotent marker Oct-4 were also decreased. Verteporfin did not alter the Akt survival pathway or the mTor pathway but there was a modest increase in LC3-IIB, a marker of autophagosome biogenesis. This study suggests that verteporfin should be further explored as an adjuvant therapy for the treatment of glioblastoma.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica , Neuroglía/efectos de los fármacos , Proteínas Nucleares/genética , Fosfoproteínas/genética , Fármacos Fotosensibilizantes/farmacología , Factores de Transcripción/genética , Verteporfina/farmacología , Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Factor de Crecimiento del Tejido Conjuntivo/antagonistas & inhibidores , Factor de Crecimiento del Tejido Conjuntivo/genética , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Proteína 61 Rica en Cisteína/antagonistas & inhibidores , Proteína 61 Rica en Cisteína/genética , Proteína 61 Rica en Cisteína/metabolismo , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/metabolismo , Humanos , Proteínas Asociadas a Microtúbulos/agonistas , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Neuroglía/metabolismo , Neuroglía/patología , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/antagonistas & inhibidores , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Fosfoproteínas/antagonistas & inhibidores , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-myc/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal , Survivin/genética , Survivin/metabolismo , Factores de Transcripción de Dominio TEA , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Proteínas Señalizadoras YAP , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Tirosina Quinasa del Receptor Axl
7.
Sci Rep ; 7: 46581, 2017 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-28429726

RESUMEN

Verteporfin (VP) was first used in Photodynamic therapy, where a non-thermal laser light (689 nm) in the presence of oxygen activates the drug to produce highly reactive oxygen radicals, resulting in local cell and tissue damage. However, it has also been shown that Verteporfin can have non-photoactivated effects such as interference with the YAP-TEAD complex of the HIPPO pathway, resulting in growth inhibition of several neoplasias. More recently, it was proposed that, another non-light mediated effect of VP is the formation of cross-linked oligomers and high molecular weight protein complexes (HMWC) that are hypothesized to interfere with autophagy and cell growth. Here, in a series of experiments, using human uveal melanoma cells (MEL 270), human embryonic kidney cells (HEK) and breast cancer cells (MCF7) we showed that Verteporfin-induced HMWC require the presence of light. Furthermore, we showed that the mechanism of this cross-linking, which involves both singlet oxygen and radical generation, can occur very efficiently even after lysis of the cells, if the lysate is not protected from ambient light. This work offers a better understanding regarding VP's mechanisms of action and suggests caution when one studies the non-light mediated actions of this drug.


Asunto(s)
Luz , Complejos Multiproteicos/metabolismo , Neoplasias , Fotoquimioterapia , Fármacos Fotosensibilizantes , Verteporfina , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Unión al ADN/metabolismo , Células HEK293 , Vía de Señalización Hippo , Humanos , Células MCF-7 , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología , Fosfoproteínas/metabolismo , Fármacos Fotosensibilizantes/farmacocinética , Fármacos Fotosensibilizantes/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , Factores de Transcripción , Verteporfina/farmacocinética , Verteporfina/farmacología , Proteínas Señalizadoras YAP
8.
Ophthalmology ; 124(5): 674-678, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28153439

RESUMEN

PURPOSE: The Retinal Detachment after Open Globe Injury (RD-OGI) Score is a clinical prediction model that was developed at the Massachusetts Eye and Ear Infirmary to predict the risk of retinal detachment (RD) after open globe injury (OGI). This study sought to validate the RD-OGI Score in an independent cohort of patients. DESIGN: Retrospective cohort study. PARTICIPANTS: The predictive value of the RD-OGI Score was evaluated by comparing the original RD-OGI Scores of 893 eyes with OGI that presented between 1999 and 2011 (the derivation cohort) with 184 eyes with OGI that presented from January 1, 2012, to January 31, 2014 (the validation cohort). METHODS: Three risk classes (low, moderate, and high) were created and logistic regression was undertaken to evaluate the optimal predictive value of the RD-OGI Score. A Kaplan-Meier survival analysis evaluated survival experience between the risk classes. MAIN OUTCOME MEASURES: Time to RD. RESULTS: At 1 year after OGI, 255 eyes (29%) in the derivation cohort and 66 eyes (36%) in the validation cohort were diagnosed with an RD. At 1 year, the low risk class (RD-OGI Scores 0-2) had a 3% detachment rate in the derivation cohort and a 0% detachment rate in the validation cohort, the moderate risk class (RD-OGI Scores 2.5-4.5) had a 29% detachment rate in the derivation cohort and a 35% detachment rate in the validation cohort, and the high risk class (RD-OGI scores 5-7.5) had a 73% detachment rate in the derivation cohort and an 86% detachment rate in the validation cohort. Regression modeling revealed the RD-OGI to be highly discriminative, especially 30 days after injury, with an area under the receiver operating characteristic curve of 0.939 in the validation cohort. Survival experience was significantly different depending upon the risk class (P < 0.0001, log-rank chi-square). CONCLUSIONS: The RD-OGI Score can reliably predict the future risk of developing an RD based on clinical variables that are present at the time of the initial evaluation after OGI.


Asunto(s)
Lesiones Oculares Penetrantes/complicaciones , Desprendimiento de Retina/epidemiología , Medición de Riesgo/métodos , Adulto , Lesiones Oculares Penetrantes/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Massachusetts/epidemiología , Persona de Mediana Edad , Reproducibilidad de los Resultados , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/etiología , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia/tendencias , Factores de Tiempo , Índices de Gravedad del Trauma , Agudeza Visual
10.
J Inorg Biochem ; 143: 34-47, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25486205

RESUMEN

Hydrazone hesperetin Schiff base (HHSB) - N-[(±)-[5,7-dihydroxy-2-(3-hydroxy-4-methoxy-phenyl)chroman-4-ylidene]amino]benzamide has been synthesized and its crystal structure was determined. This compound was used for the formation of Cu(II) complexes in solid state and in solution which were characterized using different spectroscopic methods. The analyses of potentiometric titration curves revealed that monomeric and dimeric complexes of Cu(II) are formed above pH7. The ESI-MS (electrospray ionization-mass spectrometry) spectra confirmed their formation. The EPR and UV-visible spectra evidenced the involvement of oxygen and nitrogen atoms in Cu(II) coordination. Hydrazone hesperetin Schiff base can show keto-enol tautomerism and coordinate Cu(II) in the keto (O(-), N, Oket) and in the enolate form (O(-), N, O(-)enol). The semi-empirical molecular orbital method PM6 and DFT (density functional theory) calculations have revealed that the more stable form of the dimeric complex is that one in which the ligand is present in the enol form. The CuHHSB complex has shown high efficiency in the cleavage of plasmid DNA in aqueous solution, indicating its potential as chemical nuclease. Studies on DNA interactions, antimicrobial and cytotoxic activities have been undertaken to gain more information on the biological significance of HHSB and copper(II)-HHSB chelate species.


Asunto(s)
Quelantes/química , Cobre/química , ADN/química , Flavanonas/química , Plásmidos/química , Hesperidina , Bases de Schiff/química
11.
J Food Sci ; 79(9): C1649-55, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25182178

RESUMEN

The overall objective of this study was to develop a decontamination method against microorganisms in cardamom (Elettaria cardamomum (L.) Maton) seeds using ozone as a decontaminating agent. Ozone treatment was conducted 3 times, at 24-h intervals, and the parameters of the process were determined assuring the least possible losses of biologically active substances (essential oils and polyphenols): ozone concentration 160 to 165.0 g/m(3) ; flow rate 0.1 L/min; pressure 0.5 atm; time 30 min. After each step of decontamination, the microbiological profile of the cardamom seeds was studied, and the contaminating microflora was identified. Next to the microbiological profile, the total polyphenol content (TPC), composition of essential oils, free radical-scavenging capacity, total antioxidant capacity, ferric-reducing antioxidant power (FRAP), and LC-MS polyphenol analysis were determined. This study shows that extract from cardamom seeds after ozone treatment is characterized by a better radical scavenging activity (IC(50) = 24.18 ± 0.04 mg/mL) than the control sample (IC(50) = 31.94 ± 0.05 mg/mL). The extract from cardamom seeds after ozone treatment showed an improved FRAP activity as well (613.64 ± 49.79 mmol TE/g compared to 480.29 ± 30.91 mmol TE/g of control sample). The TPC and the total antioxidant capacity were negatively affected, respectively, 41.2% and 16.2%, compared to the control sample.


Asunto(s)
Elettaria/química , Ozono/química , Polifenoles/química , Semillas/química , Elettaria/microbiología , Microbiología de Alimentos , Depuradores de Radicales Libres/química , Aceites Volátiles/química , Extractos Vegetales/química , Aceites de Plantas/química , Semillas/microbiología
12.
Int J Oncol ; 45(6): 2311-24, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25215935

RESUMEN

Recent studies suggest that the anti-diabetic drug metformin may reduce the risk of cancer and have anti-proliferative effects for some but not all cancers. In this study, we examined the effects of metformin on human retinoblastoma cell proliferation in vitro and in vivo. Two different human retinoblastoma cell lines (Y79, WERI) were treated with metformin in vitro and xenografts of Y79 cells were established in nu/nu immune-deficient mice and used to assess the effects of pharmacological levels of metformin in vivo. Metformin inhibited proliferation of the retinoblastoma cells in vitro. Similar to other studies, high concentrations of metformin (mM) blocked the cell cycle in G0­G1, indicated by a strong decrease of G1 cyclins, especially cyclin D, cyclin-dependent kinases (4 and 6), and flow cytometry assessment of the cell cycle. This was associated with activation of AMPK, inhibition of the mTOR pathways and autophagy marker LC3B. However, metformin failed to suppress growth of xenografted tumors of Y79 human retinoblastoma cells in nu/nu mice, even when treated with a maximally tolerated dose level achieved in human patients. In conclusion, suprapharmacological levels (mM) of metformin, well above those tolerated in vivo, inhibited the proliferation of retinoblastoma cells in vitro. However, physiological levels of metformin, such as seen in the clinical setting, did not affect the growth of retinoblastoma cells in vitro or in vivo. This suggests that the potential beneficial effects of metformin seen in epidemiological studies may be limited to specific tumor types or be related to indirect effects/mechanisms not observed under acute laboratory conditions.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Metformina/administración & dosificación , Retinoblastoma/tratamiento farmacológico , Proteínas Quinasas Activadas por AMP/biosíntesis , Animales , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Retinoblastoma/genética , Retinoblastoma/patología , Serina-Treonina Quinasas TOR/biosíntesis , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Exp Eye Res ; 124: 67-73, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24837142

RESUMEN

Verteporfin (VP), a benzoporphyrin derivative, is clinically used in photodynamic therapy for neovascular macular degeneration. Recent studies indicate that VP may inhibit growth of hepatoma cells without photoactivation through inhibition of YAP-TEAD complex. In this study, we examined the effects of VP without light activation on human retinoblastoma cell lines. Verteporfin but not vehicle control inhibited the growth, proliferation and viability of human retinoblastoma cell lines (Y79 and WERI) in a dose-dependent manner and was associated with downregulation of YAP-TEAD associated downstream proto-oncogenes such as c-myc, Axl, and surviving. In addition VP affected signals involved in cell migration and angiogenesis such as CTGF, cyr61, and VEGF-A but was not associated with significant effect on the mTOR/autophagy pathway. Of interest the pluripotency marker Oct4 were downregulated by Verteporfin treatment. Our results indicate that the clinically used photosensitizer VP is a potent inhibitor of cell growth in retinoblastoma cells, disrupting YAP-TEAD signaling and pluripotential marker OCT4. This study highlights for the first time the role of the YAP-TEAD pathway in Retinoblastoma and suggests that VP may be a useful adjuvant therapeutic tool in treating Rb patients.


Asunto(s)
Fotoquimioterapia/métodos , Porfirinas/uso terapéutico , Retina/patología , Neoplasias de la Retina/tratamiento farmacológico , Retinoblastoma/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Preescolar , Relación Dosis-Respuesta a Droga , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/uso terapéutico , Porfirinas/administración & dosificación , Retina/efectos de los fármacos , Neoplasias de la Retina/patología , Retinoblastoma/patología , Células Tumorales Cultivadas , Verteporfina
14.
Invest Ophthalmol Vis Sci ; 55(7): 4175-85, 2014 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-24781943

RESUMEN

PURPOSE: To evaluate the effects and mechanism of aminoimidazole carboxamide ribonucleotide (AICAR), an AMP-dependent kinase (AMPK) activator, on the growth of uveal melanoma cell lines. METHODS: Four different cell lines were treated with AICAR (1-4 mM). Cell growth was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. Cell cycle analysis was conducted by flow cytometry; additionally, expression of cell-cycle control proteins, cell growth transcription factors, and downstream effectors of AMPK were determined by RT-PCR and Western blot. RESULTS: Aminoimidazole carboxamide ribonucleotide inhibited cell growth, induced S-phase arrest, and led to AMPK activation. Aminoimidazole carboxamide ribonucleotide treatment was associated with inhibition of eukaryotic translation initiation factor 4E-BP1 phosphorylation, a marker of mammalian target of rapamycin (mTOR) pathway activity. Aminoimidazole carboxamide ribonucleotide treatment was also associated with downregulation of cyclins A and D, but had minimal effects on the phosphorylation of ribosomal protein S6 or levels of the macroautophagy marker LC3B. The effects of AICAR were abolished by treatment with dipyridamole, an adenosine transporter inhibitor that blocks the entry of AICAR into cells. Treatment with adenosine kinase inhibitor 5-iodotubericidin, which inhibits the conversion of AICAR to its 5'-phosphorylated ribotide 5-aminoimidazole-4-carboxamide-1-D-ribofuranosyl-5'-monophosphate (ZMP; the direct activator of AMPK), reversed most of the growth-inhibitory effects, indicating that some of AICAR's antiproliferative effects are mediated at least partially through AMPK activation. CONCLUSIONS: Aminoimidazole carboxamide ribonucleotide inhibited uveal melanoma cell proliferation partially through activation of the AMPK pathway and downregulation of cyclins A1 and D1.


Asunto(s)
Aminoimidazol Carboxamida/análogos & derivados , Activación Enzimática/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Melanoma/genética , Fosfotransferasas (Aceptor del Grupo Fosfato)/metabolismo , ARN Neoplásico/genética , Ribonucleótidos/farmacología , Serina-Treonina Quinasas TOR/genética , Neoplasias de la Úvea/genética , Aminoimidazol Carboxamida/farmacología , Western Blotting , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citometría de Flujo , Humanos , Melanoma/tratamiento farmacológico , Melanoma/enzimología , Fosfotransferasas (Aceptor del Grupo Fosfato)/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Serina-Treonina Quinasas TOR/metabolismo , Neoplasias de la Úvea/tratamiento farmacológico , Neoplasias de la Úvea/enzimología
15.
PLoS One ; 9(3): e91849, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24647208

RESUMEN

EGFL7 is a secreted angiogenic factor, which in contrast to the well-known secreted angiogenic molecules VEGF and FGF-2, is almost exclusively expressed by endothelial cells and may act in an autocrine fashion. Prior studies have shown EGFL7 to mediate its angiogenic effects by interfering with the Notch pathway and/or via the intronic miR126. Less is known about its effects on VEGF signaling. We wanted to investigate the role of epidermal growth factor-like domain 7 (EGFL7) in VEGF-driven angiogenesis using an ex vivo Matrigel-embedded mouse eye cup assay and siRNA mediated knockdown of EGFL7 by siRNA. Our results suggested that VEGF-induced vascular tube formation was significantly impaired after siRNA downregulation of EGFL7. In addition, knockdown of EGFL7 suppressed VEGF upregulation of phospho-Akt and phospho-Erk(1/2) in endothelial cells, but did not alter VEGFR phosphorylation and neuropilin-1 protein expression or miR126 expression. Thus, in conclusion, EGFL7 is required for VEGF upregulation of the Akt/Erk (1/2) pathway during angiogenesis, and may represent a new therapeutic target in diseases of pathological neovascularization.


Asunto(s)
Bioensayo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Técnicas In Vitro , Neovascularización Fisiológica/efectos de los fármacos , Proteínas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacología , Animales , Proteínas de Unión al Calcio , Familia de Proteínas EGF , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Activación Enzimática/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Ratones Endogámicos C57BL , Neuropilina-1/metabolismo , Fosforilación/efectos de los fármacos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
16.
PLoS One ; 8(1): e52852, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23300996

RESUMEN

5-Aminoimidazole-4-carboxamide-1-ß-4-ribofuranoside (AICAR), an analog of AMP is widely used as an activator of AMP-kinase (AMPK), a protein that regulates the responses of the cell to energy change. Recently, we showed that AICAR-induced AMPK activation inhibits the growth of retinoblastoma cells in vitro by decreasing cyclins and by inducing apoptosis and S-phase arrest. In this study, we investigated the effects of AMPK activator AICAR on the growth of retinoblastoma in vivo. Intraperitoneal injection of AICAR resulted in 48% growth inhibition of Y79 retinoblastoma cell tumors in mice. Tumors isolated from mice treated with AICAR had decreased expression of Ki67 and increased apoptotic cells (TUNEL positive) compared with the control. In addition, AICAR treatment suppressed significantly tumor vessel density and macrophage infiltration. We also showed that AICAR administration resulted in AMPK activation and mTOR pathway inhibition. Paradoxically observed down-regulation of p21, which indicates that p21 may have a novel function of an oncogene in retinoblastoma tumor. Our results indicate that AICAR treatment inhibited the growth of retinoblastoma tumor in vivo via AMPK/mTORC1 pathway and by apoptogenic, anti-proliferative, anti-angiogenesis mechanism. AICAR is a promising novel non-chemotherapeutic drug that may be effective as an adjuvant in treating Retinoblastoma.


Asunto(s)
Aminoimidazol Carboxamida/análogos & derivados , Antineoplásicos/farmacología , Apoptosis , Neovascularización Patológica/tratamiento farmacológico , Retinoblastoma/tratamiento farmacológico , Ribonucleótidos/farmacología , Aminoimidazol Carboxamida/metabolismo , Aminoimidazol Carboxamida/farmacología , Animales , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Ciclinas/metabolismo , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Ribonucleótidos/metabolismo , Fase S
17.
Proc Natl Acad Sci U S A ; 109(7): 2388-93, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-22308397

RESUMEN

The differentiation of cilia is mediated by kinesin-driven transport. As the function of kinesins in vertebrate ciliogenesis is poorly characterized, we decided to determine the role of kinesin-2 family motors--heterotrimeric kinesin-II and the homodimeric Kif17 kinesin--in zebrafish cilia. We report that kif17 is largely dispensable for ciliogenesis; kif17 homozygous mutant animals are viable and display subtle morphological defects of olfactory cilia only. In contrast to that, the kif3b gene, encoding a heterotrimeric kinesin subunit, is necessary for cilia differentiation in most tissues, although exceptions exist, and include photoreceptors and a subset of hair cells. Cilia of these cell types persist even in kif3b/kif17 double mutants. Although we have not observed a functional redundancy of kif3b and kif17, kif17 is able to substitute for kif3b in some cilia. In contrast to kif3b/kif17 double mutants, simultaneous interference with kif3b and kif3c leads to the complete loss of photoreceptor and hair cell cilia, revealing redundancy of function. This is in agreement with the idea that Kif3b and Kif3c motor subunits form complexes with Kif3a, but not with each other. Interestingly, kif3b mutant photoreceptor cilia differentiate with a delay, suggesting that kif3c, although redundant with kif3b at later stages of differentiation, is not active early in photoreceptor ciliogenesis. Consistent with that, the overexpression of kif3c in kif3b mutants rescues early photoreceptor cilia defects. These data reveal unexpected diversity of functional relationships between vertebrate ciliary kinesins, and show that the repertoire of kinesin motors changes in some cilia during their differentiation.


Asunto(s)
Cilios , Cinesinas/metabolismo , Cinesinas/fisiología , Animales , Secuencia de Bases , Cartilla de ADN , Homocigoto , Inmunohistoquímica , Cinesinas/genética , Mutación , Reacción en Cadena de la Polimerasa , Pez Cebra
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