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1.
Biol Reprod ; 110(3): 509-520, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38123510

RESUMO

Granulosa cell tumors are relatively rare, posing challenges for comprehension and therapeutic development due to limited cases and preclinical models. Metabolic reprogramming, a hallmark of cancer, manifests in granulosa cell tumors with notable lipid accumulation and increased expression of peroxisome proliferator-activated receptor gamma (PPARγ), a key lipid metabolism regulator. The roles of these features, however, remain unclear. In our previous work, we established a granulosa cell tumor model in mice by introducing a constitutively active Pik3ca mutant in oocytes, enabling the study of predictable tumor patterns from postnatal day 50. In this study, we characterized metabolic alterations during tumorigenesis (postnatal day 8 to day 50) and tumor growth (day 50 to day 65) in this model and explored the impact of PPARγ antagonism on human granulosa cell tumor proliferation. The tumor exhibited significant lipid accumulation, with PPARγ and the proliferation marker Ki67 co-localizing at postnatal day 65. Transcriptome analysis demonstrates that pathways for lipid metabolism and mitochondrial oxidation are promoted during tumorigenesis and tumor growth, respectively. Overlappingly upregulated genes during tumorigenesis and tumor growth are associated with lipid metabolism pathways. Correspondingly, mouse granulosa cell tumor shows overexpression of peroxisome proliferator-activated receptor gamma and DGAT2 proteins at postnatal day 65. Furthermore, GW9662 reduces the proliferation of KGN human granulosa cell tumor cells and decreases the phosphorylation of AKT and SMAD3. Our findings identify metabolic abnormalities in ooPIK3CA* granulosa cell tumor model and suggest peroxisome proliferator-activated receptor gamma as a potential driver for primary granulosa cell tumor growth.


Assuntos
Tumor de Células da Granulosa , Neoplasias Ovarianas , Feminino , Humanos , Animais , Camundongos , Tumor de Células da Granulosa/genética , Tumor de Células da Granulosa/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Carcinogênese , Lipídeos
2.
FASEB J ; 34(10): 13885-13899, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32830364

RESUMO

Chemotherapy directly or indirectly affects organs in a short-term or continuous manner. Endocrine organs are especially sensitive to cancer treatment, leading to concerns among patients regarding their quality of life afterward. Side effects to the ovary include damage to the ovarian reserve, resulting in follicle loss, endocrine hormone deficiency, and infertility. It has been previously demonstrated that continuous treatment with 2 mg/kg cisplatin for 15 days can activate primordial follicles, suggesting that the response in the oocytes of primordial follicles was dependent on cisplatin concentration and administration frequency. However, our results demonstrate that continuous treatment with 2 mg/kg cisplatin for 15 days leads to the same consequence as with the continuous treatment of 5 mg/kg cisplatin: the death of oocytes in primordial follicles without indication of activation. Moreover, animals co-injected with melatonin and cisplatin did not display any significant differences from those treated with cisplatin only contrary to the known results. 6-hydroxymelatonin, a metabolite of melatonin, could not prevent follicle destruction, implying that melatonin does not confer the protection of ovarian follicles, either directly or indirectly. Altogether, our data support that fertoprotectants against cisplatin must target molecules that control cell death pathways in the oocytes of primordial follicles.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Oócitos/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Animais , Antineoplásicos/administração & dosagem , Morte Celular , Cisplatino/administração & dosagem , Feminino , Fármacos para a Fertilidade/farmacologia , Melatonina/farmacologia , Camundongos , Folículo Ovariano/citologia
3.
Ophthalmic Physiol Opt ; 41(4): 768-781, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33682940

RESUMO

PURPOSE: A fundamental clinical skill is the recognition of artefacts within the outputs of advanced imaging modalities. However, current teaching programmes of healthcare practitioners are becoming increasingly challenged to provide practical exposure within an already crowded curriculum. This study evaluates the impact of a novel work-integrated teaching model on the confidence and competence of clinicians in the use of optical coherence tomography (OCT) and the recognition of its artefacts. The outcomes were then used to develop a model to predict performance and guide teaching strategies. METHODS: We prospectively evaluated a 6-week clinical placement for final year optometry students within a diagnostic eye clinic in 2018-2020. Participants completed a quiz on the identification of common OCT artefacts and rated their confidence levels on key areas of OCT application using a five-point Likert scale. Both were completed before (pre-rotation) and after (post-rotation) the placement. The cohort was divided into two groups; the first group was used to assess the impact of the placement and derive the prediction model for post-placement performance, which was then validated against the second group. RESULTS: A significant improvement in detecting OCT imaging artefacts was seen upon completion of the placement, which was greater in participants with lower entry level performance. Across all OCT artefact subtypes, there was an improvement in detecting segmentation error, delineation error and media opacities. A model predicting post-placement student performance was developed using entry level knowledge base as the key dependent variable. Self-rated confidence improved across all domains of OCT application but was not found to be a direct predictor of actual performance. CONCLUSIONS: These results highlight the benefit of a work-integrated learning programme on both academic performance and confidence whilst identifying entry level knowledge base as the key variable predicting improvement. Tailored teaching incorporating entering knowledge is the best predictor of improvement during clinical placements. Integrating clinicians into a work-integrated setting with tailored teaching and comprehensive practical exposure can be an effective method for training future or current healthcare professionals.


Assuntos
Competência Clínica , Optometria , Olho , Humanos , Estudantes , Ensino , Tomografia de Coerência Óptica
4.
Int J Mol Sci ; 22(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34445673

RESUMO

The transcription factor p63, one of the p53 family members, plays an essential role in regulating maternal reproduction and genomic integrity as well as epidermal development. TP63 (human)/Trp63 (mouse) produces multiple isoforms: TAp63 and ΔNp63, which possess a different N-terminus depending on two different promoters, and p63a, p63b, p63g, p63δ, and p63ε as products of alternative splicing at the C-terminus. TAp63 expression turns on in the nuclei of primordial germ cells in females and is maintained mainly in the oocyte nuclei of immature follicles. It has been established that TAp63 is the genomic guardian in oocytes of the female ovaries and plays a central role in determining the oocyte fate upon oocyte damage. Lately, there is increasing evidence that TP63 mutations are connected with female infertility, including isolated premature ovarian insufficiency (POI) and syndromic POI. Here, we review the biological functions of p63 in females and discuss the consequences of p63 mutations, which result in infertility in human patients.


Assuntos
Fertilidade/genética , Transativadores/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Processamento Alternativo/genética , Animais , Núcleo Celular/metabolismo , Feminino , Genes p53/genética , Humanos , Camundongos , Mutação/genética , Oócitos/metabolismo , Ovário/metabolismo , Insuficiência Ovariana Primária/metabolismo , Isoformas de Proteínas/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo
5.
Proc Natl Acad Sci U S A ; 114(28): E5664-E5672, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28652347

RESUMO

Here we investigated in primary human erythroid tissues a downstream element of the heterochronic let-7 miRNA pathway, the insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1), for its potential to affect the hemoglobin profiles in human erythroblasts. Comparison of adult bone marrow to fetal liver lysates demonstrated developmental silencing in IGF2BP1. Erythroid-specific overexpression of IGF2BP1 caused a nearly complete and pancellular reversal of the adult pattern of hemoglobin expression toward a more fetal-like phenotype. The reprogramming of hemoglobin expression was achieved at the transcriptional level by increased gamma-globin combined with decreased beta-globin transcripts resulting in gamma-globin rising to 90% of total beta-like mRNA. Delta-globin mRNA was reduced to barely detectable levels. Alpha-globin levels were not significantly changed. Fetal hemoglobin achieved levels of 68.6 ± 3.9% in the IGF2BP1 overexpression samples compared with 5.0 ± 1.8% in donor matched transduction controls. In part, these changes were mediated by reduced protein expression of the transcription factor BCL11A. mRNA stability and polysome studies suggest IGF2BP1 mediates posttranscriptional loss of BCL11A. These results suggest a mechanism for chronoregulation of fetal and adult hemoglobin expression in humans.


Assuntos
Proteínas de Transporte/metabolismo , Eritroblastos/metabolismo , Hemoglobina Fetal/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Proteínas Nucleares/metabolismo , Proteínas de Ligação a RNA/metabolismo , Medula Óssea/metabolismo , Células HEK293 , Proteína HMGA2/metabolismo , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fígado/embriologia , Fenótipo , RNA Mensageiro/metabolismo , Proteínas Repressoras , Globinas beta/metabolismo , gama-Globinas/metabolismo
6.
Ophthalmic Physiol Opt ; 39(4): 294-307, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31180155

RESUMO

PURPOSE: We aimed to determine myopia control efficacy with novel contact lenses (CL) that (1) reduced both central and peripheral defocus, and (2) provided extended depth of focus with better global retinal image quality for points on, and anterior to, the retina and degraded for points posterior to the retina. METHODS: Children (n = 508, 8-13 years) with cycloplegic spherical equivalent (SE) -0.75 to -3.50D were enrolled in a prospective, double blind trial and randomised to one of five groups: (1) single vision, silicone hydrogel (SH) CL; (2) two groups wearing SH CL that imposed myopic defocus across peripheral and central retina (test CL I and II; +1.00D centrally and +2.50 and +1.50 for CL I and II at 3 mm semi-chord respectively); and (3) two groups wearing extended depth of focus (EDOF) hydrogel CL incorporating higher order aberrations to modulate retinal image quality (test CL III and IV; extended depth of focus of up to +1.75D and +2.50D respectively). Cycloplegic autorefraction and axial length (AL) measurements were conducted at six monthly intervals. Compliance to lens wear was assessed with a diary and collected at each visit. Additionally, subjective responses to various aspects of lens wear were assessed. The trial commenced in February 2014 and was terminated in January 2017 due to site closure. Myopia progression over time between groups was compared using linear mixed models and where needed post hoc analysis with Bonferroni corrections conducted. RESULTS: Myopia progressed with control CL -1.12 ± 0.51D/0.58 ± 0.27 mm for SE/AL at 24 months. In comparison, all test CL had reduced progression with SE/AL ranging from -0.78D to -0.87D/0.41-0.46 mm at 24 months (AL: p < 0.05 for all test CL; SE p < 0.05 for test CL III and IV) and represented a reduction in axial length elongation of about 22% to 32% and reduction in spherical equivalent of 24% to 32%. With test CL, a greater slowing ranging from 26% to 43% was observed in compliant wearers (≥6 days per week; Control CL: -0.64D/0.30 mm and -1.14D/0.58 mm vs test CL: -0.42D to -0.47D/0.12-0.18 mm and -0.70 to -0.81D/0.19-0.25 mm at 12 and 24 months respectively). CONCLUSIONS: Contact lenses that either imposed myopic defocus at the retina or modulated retinal image quality resulted in a slower progression of myopia with greater efficacy seen in compliant wearers. Importantly, there was no difference in the myopia control provided by either of these strategies.


Assuntos
Lentes de Contato Hidrofílicas , Miopia Degenerativa/terapia , Adolescente , Análise de Variância , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Miopia Degenerativa/prevenção & controle , Estudos Prospectivos , Desenho de Prótese
7.
Bioorg Med Chem ; 26(2): 376-385, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29248353

RESUMO

Disruption of protein geranylgeranylation via inhibition of geranylgeranyl diphosphate synthase (GGDPS) represents a novel therapeutic strategy for a variety of malignancies, especially those characterized by excessive protein secretion such as multiple myeloma. Our work has demonstrated that some isoprenoid triazole bisphosphonates are potent and selective inhibitors of GGDPS. Here we present the synthesis and biological evaluation of a new series of isoprenoid triazoles modified by incorporation of a methyl group at the α-carbon. These studies reveal that incorporation of an α-methyl substituent enhances the potency of these compounds as GGDPS inhibitors, and, in the case of the homogeranyl/homoneryl series, abrogates the effects of olefin stereochemistry on inhibitory activity. The incorporation of the methyl group allowed preparation of a POM-prodrug, which displayed a 10-fold increase in cellular activity compared to the corresponding salt. These studies form the basis for future preclinical studies investigating the anti-myeloma activity of these novel α-methyl triazole bisphosphonates.


Assuntos
Difosfonatos/farmacologia , Inibidores Enzimáticos/farmacologia , Farnesiltranstransferase/antagonistas & inibidores , Terpenos/farmacologia , Triazóis/farmacologia , Linhagem Celular Tumoral , Difosfonatos/síntese química , Difosfonatos/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Farnesiltranstransferase/metabolismo , Humanos , Metilação , Estrutura Molecular , Relação Estrutura-Atividade , Terpenos/síntese química , Terpenos/química , Triazóis/síntese química , Triazóis/química
8.
Optom Vis Sci ; 90(7): 674-81, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23792305

RESUMO

PURPOSE: To report the performance of various contact lenses and lens care solution combinations based on the combined response of subjective comfort and adverse events (AEs). METHODS: A retrospective analysis of 28 lens/solution combinations each tested on approximately 40 participants who wore their assigned combination on a daily wear basis and were followed for a 3-month period, with visits at baseline, 2 weeks, and 1 and 3 months. Lenses included frequent replacement and daily disposables. Solutions included hydrogen peroxide and multipurpose types. Subjective comfort (scale of 1 to 10) and AEs were collected and reported as a group mean and percentage, respectively. The data were converted into a ratio between 0 and 1 to represent the relative performance within the combination series, with a higher ratio indicating better performance in both AE rates and comfort. RESULTS: The overall AE rate was 3.6 events per 100 participant-months (95% confidence interval [95% CI], 2.7 to 4.7%). The rate was found to be lower in daily disposables compared with that in daily wear lenses (3.1 vs. 10.9%, p < 0.001). The overall comfort on insertion rating was 8.3 (95% CI, 8.1 to 8.4), and comfort at end of day was 7.2 (95% CI, 7.0 to 7.4). Based on the 28 lens/solution combinations, there was no significant correlation between overall AE rates and comfort on insertion or at end of day (Pearson correlation, -0.34, p = 0.08; and Pearson correlation, -0.23, p = 0.25, respectively). Less than 18% of the combinations tested combined good comfort with low AE rates. CONCLUSIONS: Both subjective comfort responses and AE rates varied according to the combination of lens type and care system in use. The combinations with the best comfort ratings did not necessarily have a favorable AE rate. Practitioners can maximize behavior with respect to both these factors by choosing an appropriate care system for the lenses they prescribe.


Assuntos
Soluções para Lentes de Contato , Lentes de Contato Hidrofílicas , Córnea/fisiologia , Satisfação do Paciente , Erros de Refração/terapia , Acuidade Visual/fisiologia , Soluções para Lentes de Contato/efeitos adversos , Lentes de Contato Hidrofílicas/efeitos adversos , Equipamentos Descartáveis , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ajuste de Prótese , Erros de Refração/fisiopatologia , Estudos Retrospectivos
9.
J Cachexia Sarcopenia Muscle ; 13(2): 1289-1301, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35044098

RESUMO

BACKGROUND: Cancer-associated cachexia (CAC) is a complex syndrome of progressive muscle wasting and adipose loss with metabolic dysfunction, severely increasing the morbidity and mortality risk in cancer patients. However, there are limited studies focused on the underlying mechanisms of the progression of CAC due to the complexity of this syndrome and the lack of preclinical models that mimics its stagewise progression. METHODS: We characterized the initiation and progression of CAC in transgenic female mice with ovarian tumours. We measured proposed CAC biomarkers (activin A, GDF15, IL-6, IL-1ß, and TNF-α) in sera (n = 6) of this mouse model. The changes of activin A and GDF15 (n = 6) were correlated with the decline of bodyweight over time. Morphometry and signalling markers of muscle atrophy (n ≥ 6) and adipose tissue wasting (n ≥ 7) were assessed during CAC progression. RESULTS: Cancer-associated cachexia symptoms of the transgenic mice model used in this study mimic the progression of CAC seen in humans, including drastic body weight loss, skeletal muscle atrophy, and adipose tissue wasting. Serum levels of two cachexia biomarkers, activin A and GDF15, increased significantly during cachexia progression (76-folds and 10-folds, respectively). Overactivation of proteolytic activity was detected in skeletal muscle through up-regulating muscle-specific E3 ligases Atrogin-1 and Murf-1 (16-folds and 14-folds, respectively) with decreasing cross-sectional area of muscle fibres (P < 0.001). Muscle wasting mechanisms related with p-p38 MAPK, FOXO3, and p-AMPKα were highly activated in concurrence with an elevation in serum activin A. Dramatic fat loss was also observed in this mouse model with decreased fat mass (n ≥ 6) and white adipocytes sizes (n = 6) (P < 0.0001). The adipose tissue wasting was based on thermogenesis, supported by the up-regulation of uncoupling protein 1 (UCP1). Fibrosis in adipose tissue was also observed in concurrence with adipose tissue loss (n ≥ 13) (p < 0.0001). CONCLUSIONS: Our novel preclinical CAC mouse model mimics human CAC phenotypes and serum biomarkers. The mouse model in this study showed proteolysis in muscle atrophy, browning in adipose tissue wasting, elevation of serum activin A and GDF15, and atrophy of pancreas and liver. This mouse line would be the best preclinical model to aid in clarifying molecular mediators of CAC and dissecting metabolic dysfunction and tissue atrophy during the progression of CAC.


Assuntos
Caquexia , Neoplasias Ovarianas , Tecido Adiposo/patologia , Animais , Caquexia/patologia , Feminino , Humanos , Camundongos , Camundongos Transgênicos , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/patologia
10.
Sci Rep ; 12(1): 1659, 2022 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-35102236

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) patients display distinct phenotypes of cachexia development, with either adipose tissue loss preceding skeletal muscle wasting or loss of only adipose tissue. Activin A levels were measured in serum and analyzed in tumor specimens of both a cohort of Stage IV PDAC patients and the genetically engineered KPC mouse model. Our data revealed that serum activin A levels were significantly elevated in Stage IV PDAC patients in comparison to age-matched non-cancer patients. Little is known about the role of activin A in adipose tissue wasting in the setting of PDAC cancer cachexia. We established a correlation between elevated activin A and remodeling of visceral adipose tissue. Atrophy and fibrosis of visceral adipose tissue was examined in omental adipose tissue of Stage IV PDAC patients and gonadal adipose tissue of an orthotopic mouse model of PDAC. Remarkably, white visceral adipose tissue from both PDAC patients and mice exhibited decreased adipocyte diameter and increased fibrotic deposition. Strikingly, expression of thermogenic marker UCP1 in visceral adipose tissues of PDAC patients and mice remained unchanged. Thus, we propose that activin A signaling could be relevant to the acceleration of visceral adipose tissue wasting in PDAC-associated cachexia.


Assuntos
Ativinas/metabolismo , Adipócitos Brancos/metabolismo , Adiposidade , Carcinoma Ductal Pancreático/metabolismo , Subunidades beta de Inibinas/metabolismo , Gordura Intra-Abdominal/metabolismo , Neoplasias Pancreáticas/metabolismo , Ativinas/genética , Adipócitos Brancos/patologia , Animais , Atrofia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Estudos de Casos e Controles , Linhagem Celular , Fibrose , Humanos , Subunidades beta de Inibinas/genética , Gordura Intra-Abdominal/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estadiamento de Neoplasias , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Transdução de Sinais , Proteína Desacopladora 1/metabolismo
11.
J Endocrinol ; 252(1): 15-30, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34647523

RESUMO

Immunotherapy has emerged at the forefront of cancer treatment. Checkpoint inhibitor pembrolizumab (KEYTRUDA), a chimeric antibody which targets programmed cell death protein 1 (PD-1), has been approved by the Food and Drug Administration (FDA) for use in pediatric patients with relapsed or refractory classical Hodgkin's lymphoma. However, there is currently no published data regarding the effects of pembrolizumab on the ovary of female pediatric patients. In this study, prepubertal immunocompetent and immunodeficient female mice were injected with pembrolizumab or anti-mouse PD-1 antibody. The number of primordial follicles significantly decreased post-injection of both pembrolizumab and anti-mouse PD-1 antibody in immunocompetent mice. However, no changes in follicle numbers were observed in immunodeficient nude mice. Superovulation test and vaginal opening experiments suggest that there is no difference in the number of cumulus-oocyte complexes (COCs) and the timing of puberty onset between the control and anti-mouse PD-1 antibody treatment groups, indicating that there is no effect on short-term fertility. Elevation of pro-inflammatory cytokine TNF-α following COX-2 upregulation was observed in the ovary. CD3+ T-cell infiltration was detected within some ovarian follicles and between stromal cells of the ovaries in mice following treatment with anti-mouse PD-1 antibody. Thus, PD-1 immune checkpoint blockade affects the ovarian reserve through a mechanism possibly involving inflammation following CD3+ T-cell infiltration.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Folículo Ovariano/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/farmacologia , Contagem de Células , Feminino , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/farmacologia , Infertilidade Feminina/induzido quimicamente , Infertilidade Feminina/patologia , Camundongos , Camundongos Nus , Oócitos/citologia , Oócitos/efeitos dos fármacos , Reserva Ovariana/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovário/fisiologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia
12.
Optom Vis Sci ; 86(4): e306-11, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19225436

RESUMO

PURPOSE: To investigate the mechanism underlying hyperopic orthokeratology (OK) by comparing the short-term clinical effect of lenses before and after central lens fenestration. METHODS: Twelve subjects (age 21 to 24 years) were fitted with rigid hyperopic OK lenses (BE Enterprises/Capricornia) in one eye only. The fellow eye acted as a non-lens wearing control. Lens specifications were matched to provide the same post lens tear film profile in all subjects. Non-fenestrated lenses were worn in the open eye for 1 h and in the closed eye for four nights. Subjective spherical equivalent refraction and corneal topography (Medmont E300) were measured at baseline, after 1 h of lens wear, and within 1 h of waking on days 1 and 4 of overnight lens wear. The lenses were then sent for three 0.75 mm fenestrations within the central optic zone, and lens wearing and measurement procedures were repeated. RESULTS: There was a statistically significant change from baseline in all variables at all visits in lens wearing eyes. Refraction changed after 1 h of lens wear, with greater effect after overnight wear. Para-central corneal flattening was apparent after 1 h of lens wear, with greater flattening after overnight wear. Central corneal steepening was only statistically significant after overnight wear. Central fenestrations did not lead to a difference in clinical effect in any variables. However, a correlation between apical corneal curvature change and refractive change became apparent only after lens fenestration. CONCLUSION: A hyperopic OK effect was established after 1 h with increased effect with longer lens wearing time. Central fenestrations did not affect the clinical outcomes, indicating that corneal compression by the lens in the para-central region as opposed to central post lens tear film suction may be the primary mechanism behind the hyperopic OK clinical effect.


Assuntos
Córnea/patologia , Córnea/fisiopatologia , Hiperopia/terapia , Procedimentos Ortoceratológicos , Topografia da Córnea , Feminino , Humanos , Hiperopia/patologia , Hiperopia/fisiopatologia , Masculino , Refração Ocular , Lágrimas/metabolismo , Fatores de Tempo , Adulto Jovem
13.
Antioxid Redox Signal ; 26(14): 748-762, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-26914345

RESUMO

AIMS: Heme derived from hemolysis is pro-oxidative and proinflammatory and promotes vaso-occlusion in murine models of sickle cell disease (SCD), suggesting that enhanced detoxification of heme may be beneficial. Nuclear factor erythroid-2-related factor-2 (Nrf2) transcription pathway is the principal cellular defense system responding to pro-oxidative and proinflammatory stress. Dimethyl fumarate (DMF), a drug approved for treatment of multiple sclerosis, provides neuroprotection by activating Nrf2-responsive genes. We hypothesized that induction of Nrf2 with DMF would be beneficial in murine SCD models. RESULTS: DMF (30 mg/kg/day) or vehicle (0.08% methyl cellulose) was administered for 3-7 days to NY1DD and HbSS-Townes SCD mice. Vaso-occlusion, a hallmark of SCD, measured in sickle mice with dorsal skinfold chambers, was inhibited by DMF. The inhibitory effect of DMF was abrogated by the heme oxygenase-1 (HO-1) inhibitor tin protoporphyrin. DMF increased nuclear Nrf2 and cellular mRNA of Nrf2-responsive genes in livers and kidneys. DMF increased heme defenses, including HO-1, haptoglobin, hemopexin, and ferritin heavy chain, although plasma hemoglobin and heme levels were unchanged. DMF decreased markers of inflammation, including nuclear factor-kappa B phospho-p65, adhesion molecules, and toll-like receptor 4. DMF administered for 24 weeks to HbSS-Townes mice decreased hepatic necrosis, inflammatory cytokines, and irregularly shaped erythrocytes and increased hemoglobin F, but did not alter hematocrits, reticulocyte counts, lactate dehydrogenase, plasma heme, or spleen weights, indicating that the beneficial effects of DMF were not attributable to decreased hemolysis. INNOVATION: These studies identify Nrf2 activation as a new therapeutic target for the treatment of SCD. CONCLUSION: DMF activates Nrf2, enhances antioxidant defenses, and inhibits inflammation and vaso-occlusion in SCD mice. Antioxid. Redox Signal. 26, 748-762.


Assuntos
Anemia Falciforme/tratamento farmacológico , Fumarato de Dimetilo/farmacologia , Inflamação/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Administração Oral , Animais , Fumarato de Dimetilo/administração & dosagem , Fumarato de Dimetilo/química , Relação Dose-Resposta a Droga , Feminino , Masculino , Camundongos , Camundongos Transgênicos
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