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1.
J Physiol Anthropol ; 43(1): 7, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297353

RESUMEN

BACKGROUND: Myopia, commonly known as near-sightedness, has emerged as a global epidemic, impacting almost one in three individuals across the world. The increasing prevalence of myopia during early childhood has heightened the risk of developing high myopia and related sight-threatening eye conditions in adulthood. This surge in myopia rates, occurring within a relatively stable genetic framework, underscores the profound influence of environmental and lifestyle factors on this condition. In this comprehensive narrative review, we shed light on both established and potential environmental and lifestyle contributors that affect the development and progression of myopia. MAIN BODY: Epidemiological and interventional research has consistently revealed a compelling connection between increased outdoor time and a decreased risk of myopia in children. This protective effect may primarily be attributed to exposure to the characteristics of natural light (i.e., sunlight) and the release of retinal dopamine. Conversely, irrespective of outdoor time, excessive engagement in near work can further worsen the onset of myopia. While the exact mechanisms behind this exacerbation are not fully comprehended, it appears to involve shifts in relative peripheral refraction, the overstimulation of accommodation, or a complex interplay of these factors, leading to issues like retinal image defocus, blur, and chromatic aberration. Other potential factors like the spatial frequency of the visual environment, circadian rhythm, sleep, nutrition, smoking, socio-economic status, and education have debatable independent influences on myopia development. CONCLUSION: The environment exerts a significant influence on the development and progression of myopia. Improving the modifiable key environmental predictors like time spent outdoors and engagement in near work can prevent or slow the progression of myopia. The intricate connections between lifestyle and environmental factors often obscure research findings, making it challenging to disentangle their individual effects. This complexity underscores the necessity for prospective studies that employ objective assessments, such as quantifying light exposure and near work, among others. These studies are crucial for gaining a more comprehensive understanding of how various environmental factors can be modified to prevent or slow the progression of myopia.


Asunto(s)
Miopía , Preescolar , Niño , Humanos , Estudios Prospectivos , Miopía/epidemiología , Miopía/genética , Miopía/prevención & control , Refracción Ocular , Acomodación Ocular , Ritmo Circadiano
2.
Acta Ophthalmol ; 102(3): e257-e271, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37786939

RESUMEN

PURPOSE: During the COVID-19 pandemic, home-based and remote learning-particularly using electronic devices-was rapidly pushed out. Increased near-work, screen time exposure and lack of outdoor time are risk factors that contribute to childhood myopia, but it is difficult to adopt recommendations from prior publications as a consistent limitation in the literature is the heterogeneity of research methodology. This review seeks to systematically evaluate how observational studies published during the pandemic have quantified and measured risk factors and myopia in school-going children and adolescents. METHODS: Three scientific databases (PubMed, CINAHL, Scopus) were systematically searched from March 2020 to April 2022. Findings from relevant studies were descriptively summarised in relation to the PICOS-based objective of the review. RESULTS: The final sample of 13 studies included research from six countries and comprised 1 411 908 children and adolescents. The majority of studies (N = 10; 76.9%) used spherical equivalent refraction (SER) of -0.5 dioptres or lower as a common definition of myopia. Most studies (77.8%) measuring screen time exposure found it higher during COVID-19 compared to pre-COVID, but only one study used objective measurement of screen time. The average critical appraisal score of the sample was only 66.1%, with a considerable number of studies failing to identify and adjust for potential confounders. CONCLUSION: Future studies should consider emergent objective and validated measures of risk factors, account for potential a priori confounders and covariates and ensure more representativeness in the sociodemographic makeup of their samples.


Asunto(s)
COVID-19 , Miopía , Adolescente , Humanos , Niño , Pandemias , COVID-19/epidemiología , COVID-19/complicaciones , Miopía/epidemiología , Miopía/etiología , Factores de Riesgo , Refracción Ocular
3.
Br J Ophthalmol ; 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37726156

RESUMEN

AIMS: To determine axial length (AL) elongation profiles in children aged 3-6 years in an Asian population. METHODS: Eligible subjects were recruited from the Growing Up in Singapore Towards Healthy Outcomes birth cohort. AL measurement was performed using IOLMaster (Carl Zeiss Meditec, Jena, Germany) at 3 and 6 years. Anthropometric measurements at birth, cycloplegic refraction at 3 and 6 years, questionnaires on the children's behavioural habits at 2 years and parental spherical equivalent refraction were performed. Multivariable linear regression model with generalised estimating equation was performed to determine factors associated with AL elongation. RESULTS: 273 eyes of 194 children were included. The mean AL increased from 21.72±0.59 mm at 3 years to 22.52±0.66 mm at 6 years (p<0.001). Myopic eyes at 6 years had greater AL elongation (1.02±0.34 mm) compared with emmetropic eyes (0.85±0.25 mm, p=0.008) and hyperopic eyes (0.74±0.16 mm, p<0.001). The 95th percentile limit of AL elongation was 1.59 mm in myopes, 1.34 mm in emmetropes and 1.00 mm in hyperopes. Greater birth weight (per 100 g, ß=0.010, p=0.02) was significantly associated with greater AL elongation from 3 to 6 years, while parental and other behavioural factors assessed at 2 years were not (all p≥0.08). CONCLUSION: In this preschool cohort, AL elongates at an average length of 0.80 mm from 3 to 6 years, with myopes demonstrating the greatest elongation. The differences in 95th percentile limits for AL elongation between myopes, emmetropes and hyperopes can be valuable information in identifying myopia development in preschool children.

4.
EBioMedicine ; 95: 104770, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37625267

RESUMEN

BACKGROUND: Large language models (LLMs) are garnering wide interest due to their human-like and contextually relevant responses. However, LLMs' accuracy across specific medical domains has yet been thoroughly evaluated. Myopia is a frequent topic which patients and parents commonly seek information online. Our study evaluated the performance of three LLMs namely ChatGPT-3.5, ChatGPT-4.0, and Google Bard, in delivering accurate responses to common myopia-related queries. METHODS: We curated thirty-one commonly asked myopia care-related questions, which were categorised into six domains-pathogenesis, risk factors, clinical presentation, diagnosis, treatment and prevention, and prognosis. Each question was posed to the LLMs, and their responses were independently graded by three consultant-level paediatric ophthalmologists on a three-point accuracy scale (poor, borderline, good). A majority consensus approach was used to determine the final rating for each response. 'Good' rated responses were further evaluated for comprehensiveness on a five-point scale. Conversely, 'poor' rated responses were further prompted for self-correction and then re-evaluated for accuracy. FINDINGS: ChatGPT-4.0 demonstrated superior accuracy, with 80.6% of responses rated as 'good', compared to 61.3% in ChatGPT-3.5 and 54.8% in Google Bard (Pearson's chi-squared test, all p ≤ 0.009). All three LLM-Chatbots showed high mean comprehensiveness scores (Google Bard: 4.35; ChatGPT-4.0: 4.23; ChatGPT-3.5: 4.11, out of a maximum score of 5). All LLM-Chatbots also demonstrated substantial self-correction capabilities: 66.7% (2 in 3) of ChatGPT-4.0's, 40% (2 in 5) of ChatGPT-3.5's, and 60% (3 in 5) of Google Bard's responses improved after self-correction. The LLM-Chatbots performed consistently across domains, except for 'treatment and prevention'. However, ChatGPT-4.0 still performed superiorly in this domain, receiving 70% 'good' ratings, compared to 40% in ChatGPT-3.5 and 45% in Google Bard (Pearson's chi-squared test, all p ≤ 0.001). INTERPRETATION: Our findings underscore the potential of LLMs, particularly ChatGPT-4.0, for delivering accurate and comprehensive responses to myopia-related queries. Continuous strategies and evaluations to improve LLMs' accuracy remain crucial. FUNDING: Dr Yih-Chung Tham was supported by the National Medical Research Council of Singapore (NMRC/MOH/HCSAINV21nov-0001).


Asunto(s)
Benchmarking , Miopía , Humanos , Niño , Motor de Búsqueda , Consenso , Lenguaje , Miopía/diagnóstico , Miopía/epidemiología , Miopía/terapia
5.
Healthc Q ; 24(SP): 55-59, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35467512

RESUMEN

A lack of mental health literacy may impact youths' ability to advocate for themselves as they seek to access and navigate the mental healthcare system. Recognizing this, members of the National Youth Action Council at the Centre for Addiction and Mental Health in Toronto, ON, developed the Youth Wellness Quest resource. This health literacy resource informs youth of possible available services, increasing their capacity to make informed mental healthcare decisions. The youth-led process of creating this resource, from development to dissemination, is described within this paper, showcasing how youth can lead the development of tools designed for youth.


Asunto(s)
Alfabetización en Salud , Servicios de Salud Mental , Adolescente , Accesibilidad a los Servicios de Salud , Humanos , Salud Mental
6.
Health Expect ; 24(2): 659-669, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33636052

RESUMEN

BACKGROUND: Less than 20% of youth who experience mental health difficulties access and receive appropriate treatment. This is exacerbated by barriers such as stigma, confidentiality concerns and lack of mental health literacy. A youth team developed the Wellness Quest: a health literacy tool to enable help-seeking youth to advocate for themselves. OBJECTIVE: To evaluate the content, presentation and utility of the Wellness Quest tool among youth. PARTICIPANTS: Participants aged 14 to 26. METHODS: A youth research team conducted five focus groups and one online survey to evaluate the Wellness Quest tool. Thematic analysis was used to analyse the qualitative data, and descriptive statistics were used to explore the survey results. MAIN RESULTS: Overall evaluations of the Wellness Quest were positive: participants felt it would be useful during their mental health help-seeking journey. Participants expressed the need for information about services for specific populations, such as Indigenous, immigrants, refugees and 2SLGBTQ + youth. They expressed that the tool should be available in complementary online and print versions. DISCUSSION: Improving mental health literacy may improve mental health by enabling youth and those who support them to recognize and respond to signs of distress and understanding where and how to get help. The Wellness Quest tool may equip youth with the knowledge to make informed decisions and advocate for their own mental health, thereby facilitating help-seeking among youth. PATIENT OR PUBLIC CONTRIBUTION: Youth as service users led all stages of the project, from designing and conducting the study and analysing the data to writing the manuscript.


Asunto(s)
Alfabetización en Salud , Servicios de Salud Mental , Adolescente , Humanos , Salud Mental , Estigma Social , Encuestas y Cuestionarios
8.
Front Immunol ; 11: 1231, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32625211

RESUMEN

Post-transplant lymphoproliferative disorder (PTLD) is a rare but potentially life-threatening complication, frequently associated with Epstein-Barr virus (EBV), which develops after solid organ or stem cell transplantation. Immunosuppression received by transplant recipients has a significant impact on the development of PTLD by suppressing the function of T cells. The preferential proliferation of NKG2A-positive natural killer (NK) cells during primary symptomatic EBV infection known as infectious mononucleosis (IM) and their reactivity toward EBV-infected B cells point to a role of NK cell in the immune control of EBV. However, NK cell-mediated immune response to EBV in immunosuppressed transplant recipients who develop PTLD remains unclear. In this study, we longitudinally analyzed the phenotype and function of different NK cell subsets in a cohort of pediatric liver transplant patients who develop PTLD and compared them to those of children with IM. We found persistently elevated plasma EBV DNA levels in the PTLD patients indicating suboptimal anti-viral immune control. PTLD patients had markedly decreased frequency of CD56dimNKG2A+Killer Immunoglobulin-like receptor (KIR)- NK cells from the time of diagnosis through remission compared to those of IM patients. Whilst the proliferation of CD56dimNKG2A+KIR- NK cells was diminished in PTLD patients, this NK cell subset maintained its ability to potently degranulate against EBV-infected B cells. Compared to cytomegalovirus (CMV)-seropositive and -negative IM patients, PTLD patients co-infected with CMV and EBV had significantly higher levels of a CMV-associated CD56dimNKG2ChiCD57+NKG2A-KIR+ NK cell subset accumulating at the expense of NKG2A+KIR- NK cells. Taken together, our data indicate that co-infection of CMV and EBV diminishes the frequency of CD56dimNKG2A+KIR- NK cells and contributes to suboptimal control of EBV in immunosuppressed children with PTLD.


Asunto(s)
Coinfección , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/inmunología , Citomegalovirus , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/inmunología , Herpesvirus Humano 4 , Células Asesinas Naturales/inmunología , Factores de Edad , Degranulación de la Célula/inmunología , Línea Celular , Preescolar , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Susceptibilidad a Enfermedades , Infecciones por Virus de Epstein-Barr/virología , Femenino , Herpesvirus Humano 4/inmunología , Humanos , Huésped Inmunocomprometido , Inmunofenotipificación , Terapia de Inmunosupresión , Inmunosupresores/administración & dosificación , Inmunosupresores/farmacocinética , Lactante , Células Asesinas Naturales/metabolismo , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Recuento de Linfocitos , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/metabolismo , Trastornos Linfoproliferativos/etiología , Masculino , Trasplante de Órganos/efectos adversos , Receptores KIR/metabolismo , Factores de Tiempo , Carga Viral
9.
Life Sci Alliance ; 3(8)2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32576602

RESUMEN

HIV and EBV are human pathogens that cause a considerable burden to worldwide health. In combination, these viruses are linked to AIDS-associated lymphomas. We found that EBV, which transforms B cells, renders them susceptible to HIV-1 infection in a CXCR4 and CD4-dependent manner in vitro and that CXCR4-tropic HIV-1 integrates into the genome of these B cells with the same molecular profile as in autologous CD4+ T cells. In addition, we established a humanized mouse model to investigate the in vivo interactions of EBV and HIV-1 upon coinfection. The respective mice that reconstitute human immune system components upon transplantation with CD34+ human hematopoietic progenitor cells could recapitulate aspects of EBV and HIV immunobiology observed in dual-infected patients. Upon coinfection of humanized mice, EBV/HIV dual-infected B cells could be detected, but were susceptible to CD8+ T-cell-mediated immune control.


Asunto(s)
Infecciones por VIH/inmunología , Infecciones por VIH/virología , Herpesvirus Humano 4/patogenicidad , Animales , Linfocitos B/metabolismo , Linfocitos B/patología , Linfocitos B/virología , Antígenos CD4/inmunología , Antígenos CD4/metabolismo , Coinfección , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades/metabolismo , Susceptibilidad a Enfermedades/virología , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por VIH/genética , Seropositividad para VIH , VIH-1/metabolismo , VIH-1/patogenicidad , Células Madre Hematopoyéticas/patología , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Receptores CXCR4/metabolismo , Receptores CXCR4/fisiología , Linfocitos T/inmunología
10.
PLoS Pathog ; 16(4): e1008477, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32251475

RESUMEN

Post-transplant lymphoproliferative disorder (PTLD) is a potentially fatal complication after organ transplantation frequently associated with the Epstein-Barr virus (EBV). Immunosuppressive treatment is thought to allow the expansion of EBV-infected B cells, which often express all eight oncogenic EBV latent proteins. Here, we assessed whether HLA-A2 transgenic humanized NSG mice treated with the immunosuppressant FK506 could be used to model EBV-PTLD. We found that FK506 treatment of EBV-infected mice led to an elevated viral burden, more frequent tumor formation and diminished EBV-induced T cell responses, indicative of reduced EBV-specific immune control. EBV latency III and lymphoproliferation-associated cellular transcripts were up-regulated in B cells from immunosuppressed animals, akin to the viral and host gene expression pattern found in EBV-PTLD. Utilizing an unbiased gene expression profiling approach, we identified genes differentially expressed in B cells of EBV-infected animals with and without FK506 treatment. Upon investigating the most promising candidates, we validated sCD30 as a marker of uncontrolled EBV proliferation in both humanized mice and in pediatric patients with EBV-PTLD. High levels of sCD30 have been previously associated with EBV-PTLD in patients. As such, we believe that humanized mice can indeed model aspects of EBV-PTLD development and may prove useful for the safety assessment of immunomodulatory therapies.


Asunto(s)
Trastornos Linfoproliferativos/inmunología , Trastornos Linfoproliferativos/virología , Tacrolimus/farmacología , Animales , Linfocitos B/metabolismo , ADN Viral , Modelos Animales de Enfermedad , Infecciones por Virus de Epstein-Barr/virología , Femenino , Perfilación de la Expresión Génica/métodos , Antígeno HLA-A2 , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Herpesvirus Humano 4/patogenicidad , Humanos , Huésped Inmunocomprometido , Inmunosupresores/farmacología , Masculino , Ratones , Ratones Endogámicos NOD , Ratones Transgénicos , Trasplante de Órganos/efectos adversos , Transcriptoma/genética , Carga Viral
11.
Nanomedicine ; 20: 102003, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31055077

RESUMEN

Triple negative breast cancers (TNBC) are aggressive malignancies for which chemotherapy is the only treatment option. Many TNBC acquire chemotherapy resistance, notably docetaxel, which has been associated with the overexpression of transcription factors (TFs), such as ENGRAILED1 (EN1). Here, we have developed a tumor delivery system for docetaxel-PGMA-PAA-nanoparticles and interference peptides designed to specifically inhibit EN1 (EN1-iPeps). To promote tumor specific targeting, we functionalized these nanoparticles with EN1-iPeps engineered with RGD sequences. We found that these peptides reduce cell viability and induce apoptosis in TNBC cells with negligible effects on normal cells (EN1-). Moreover, EN1-RGD-iPeps-mediated nanoparticle internalization into breast cancer cells was via integrins and intravenous injection of this nanoformulation increased tumor accumulation. Furthermore, docetaxel nanoparticles functionalized with EN1-RGD-iPeps significantly reduced TNBC growth both in vitro and in vivo without showing toxicity. Our results suggest that this targeted nanoformulation represents a new and safe therapeutic approach for chemoresistant TNBCs.


Asunto(s)
Docetaxel/uso terapéutico , Proteínas de Homeodominio/metabolismo , Nanopartículas/química , Oligopéptidos/química , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Docetaxel/farmacología , Endocitosis/efectos de los fármacos , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Células 3T3 NIH , Polímeros/química , Distribución Tisular/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/patología
12.
Front Microbiol ; 9: 416, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29599759

RESUMEN

Long term carriers were shown to generate robust polyfunctional T cell (PFC) responses against lytic and latent antigens of Epstein-Barr virus (EBV). However, the time of emergence of PFC responses against EBV antigens, pattern of immunodominance and difference between CD4+ and CD8+ T cell responses during various stages of EBV infection are not clearly understood. A longitudinal study was performed to assess the development of antigen-specific PFC responses in children diagnosed to have primary symptomatic (infectious mononucleosis [IM]) and asymptomatic (AS) EBV infection. Evaluation of IFN-γ secreting CD8+ T cell responses upon stimulation by HLA class I-specific peptides of EBV lytic and latent proteins by ELISPOT assay followed by assessment of CD4+ and CD8+ PFC responses upon stimulation by a panel of overlapping EBV peptides for co-expression of IFN-γ, TNF-α, IL-2, perforin and CD107a by flow cytometry were performed. Cytotoxicity of T cells against autologous lymphoblastoid cell lines (LCLs) as well as EBV loads in PBMC and plasma were also determined. Both IM and AS patients had elevated PBMC and plasma viral loads which declined steadily during a 12-month period from the time of diagnosis whilst decrease in the magnitude of CD8+ T cell responses toward EBV lytic peptides in contrast to increase toward latent peptides was shown with no significant difference between those of IM and AS patients. Both lytic and latent antigen-specific CD4+ and CD8+ T cells demonstrated polyfunctionality (defined as greater or equal to three functions) concurrent with enhanced cytotoxicity against autologous LCLs and steady decrease in plasma and PBMC viral loads over time. Immunodominant peptides derived from BZLF1, BRLF1, BMLF1 and EBNA3A-C proteins induced the highest proportion of CD8+ as well as CD4+ PFC responses. Diverse functional subtypes of both CD4+ and CD8+ PFCs were shown to emerge at 6-12 months. In conclusion, EBV antigen-specific CD4+ and CD8+ PFC responses emerge during the first year of primary EBV infection, with greatest responses toward immunodominant epitopes in both lytic and latent proteins, correlating to steady decline in PBMC and plasma viral loads.

13.
Chem Sci ; 8(4): 2923-2930, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28451358

RESUMEN

Tools for editing the genome and epigenome have revolutionised the field of molecular biology and represent a new frontier in targeted therapeutic intervention. Although efficiencies and specificities of genome editing technologies have improved with the development of TALEs and CRISPR platforms, intracellular delivery of these larger constructs still remains a challenge using existing delivery agents. Viral vectors, including lentiviruses and adeno-associated viruses, as well as some non-viral strategies, such as cationic polymers and liposomes, are limited by packaging capacity, poor delivery, toxicity, and immunogenicity. We report a highly controlled synthetic strategy to engineer a flexible dendritic polymer using click chemistry to overcome the aforementioned delivery challenges associated with genome engineering technologies. Using a systematic approach, we demonstrate that high transfection efficiencies and packaging capacity can be achieved using this non-viral delivery methodology to deliver zinc fingers, TALEs and CRISPR/dCas9 platforms.

14.
Exp Hematol ; 46: 70-82.e10, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27751872

RESUMEN

Erythropoiesis is controlled principally through erythropoietin (Epo) receptor signaling, which involves Janus kinase 2 (JAK2) and Lyn tyrosine kinase, both of which are important for regulating red blood cell (RBC) development. Negative regulation of Lyn involves C-Src kinase (Csk)-mediated phosphorylation of its C-terminal tyrosine, which is facilitated by the transmembrane adaptor Csk-binding protein (Cbp). Although Cbp has significant functions in controlling Lyn levels and activity in erythroid cells in vitro, its importance to primary erythroid cell development and signaling has remained unclear. To address this, we assessed the consequence of loss of Cbp on the erythroid compartment in vivo and whether Epo-responsive cells isolated from Cbp-knockout mice exhibited altered signaling. Our data show that male Cbp-/- mice display a modest but significant alteration to late erythroid development in bone marrow with evidence of increased erythrocytes in the spleen, whereas female Cbp-/- mice exhibit a moderate elevation in early erythroid progenitors (not seen in male mice) that does not influence the later steps in RBC development. In isolated primary erythroid cells and cell lines generated from Cbp-/- mice, survival signaling through Lyn/Akt/FoxO3 was elevated, resulting in sustained viability during differentiation. The high Akt activity disrupted GAB2/SHP-2 feedback inhibition of Lyn; however, the elevated Lyn activity also increased inhibitory signaling via SHP-1 to restrict the Erk1/2 pathway. Interestingly, whereas loss of Cbp led to mild changes to late RBC development in male mice, this was not apparent in female Cbp-/- mice, possibly due to their elevated estrogen, which is known to facilitate early progenitor self-renewal.


Asunto(s)
Diferenciación Celular , Células Eritroides/citología , Células Eritroides/metabolismo , Eritropoyesis , Proteínas de la Membrana/metabolismo , Fosfoproteínas/metabolismo , Familia-src Quinasas/metabolismo , Animales , Diferenciación Celular/genética , Línea Celular , Supervivencia Celular/genética , Activación Enzimática , Femenino , Proteína Forkhead Box O3/metabolismo , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Modelos Biológicos , Fosfoproteínas/genética , Unión Proteica , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
15.
Australas J Dermatol ; 58(3): 189-193, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26914474

RESUMEN

BACKGROUND/OBJECTIVES: In Mohs micrographic surgery (MMS) the dermatologist serves as surgeon, pathologist and reconstructive surgeon. Analysis of the factors that play a part in determining defect size and closure type may result in better patient outcomes. The objective was to identify factors contributing to the defect size and closure method employed in MMS. METHODS: Retrospective analysis of all MMS performed for non-melanoma skin cancers (NMSC) of the head at the Skin and Cancer Foundation Australia, Westmead, between 1 January and 31 December 2007. RESULTS: Tumor size was the main factor involved in the final defect size (r2 : 0.60, P < 0.001), but the sex and age of the patient, tumour pathology, site and surgeon were also significantly associated with the final defect size. In a multivariate analysis, only sex did not remain as an independent factor. Regarding closure method, the age of the patient, defect size, site and surgeon were significantly associated, but patient's age did not remain significant in the multivariate analysis. CONCLUSION: Our study has demonstrated that the performing surgeon is a relevant factor in the determination of defect size and repair methods in MMS. The factors underlying this variability require further study as decisions on closure method should be made objectively, based on patient-related and tumour-related factors. As expected, the location and size of the defect are the other factors that determine the chosen method of repair.


Asunto(s)
Carcinoma Basocelular/cirugía , Carcinoma de Células Escamosas/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Cirugía de Mohs/métodos , Neoplasias Cutáneas/cirugía , Técnicas de Cierre de Heridas , Factores de Edad , Anciano , Carcinoma Basocelular/patología , Carcinoma de Células Escamosas/patología , Oído , Cara , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Pautas de la Práctica en Medicina , Cuero Cabelludo , Neoplasias Cutáneas/patología , Colgajos Quirúrgicos , Carga Tumoral
16.
Oncotarget ; 7(37): 60535-60554, 2016 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-27528034

RESUMEN

The aberrant epigenetic silencing of tumor suppressor genes (TSGs) plays a major role during carcinogenesis and regaining these dormant functions by engineering of sequence-specific epigenome editing tools offers a unique opportunity for targeted therapies. However, effectively normalizing the expression and regaining tumor suppressive functions of silenced TSGs by artificial transcription factors (ATFs) still remains a major challenge. Herein we describe novel combinatorial strategies for the potent reactivation of two class II TSGs, MASPIN and REPRIMO, in cell lines with varying epigenetic states, using the CRISPR/dCas9 associated system linked to a panel of effector domains (VP64, p300, VPR and SAM complex), as well as with protein-based ATFs, Zinc Fingers and TALEs. We found that co-delivery of multiple effector domains using a combination of CRISPR/dCas9 and TALEs or SAM complex maximized activation in highly methylated promoters. In particular, CRISPR/dCas9 VPR with SAM upregulated MASPIN mRNA (22,145-fold change) in H157 lung cancer cells, with accompanying re-expression of MASPIN protein, which led to a concomitant inhibition of cell proliferation and induction of apoptotic cell death. Consistently, CRISPR/dCas9 VP64 with SAM upregulated REPRIMO (680-fold change), which led to phenotypic reprogramming in AGS gastric cancer cells. Altogether, our results outlined novel sequence-specific, combinatorial epigenome editing approaches to reactivate highly methylated TSGs as a promising therapy for cancer and other diseases.


Asunto(s)
Sistemas CRISPR-Cas/genética , Proteínas de Homeodominio/genética , Neoplasias Pulmonares/metabolismo , ARN Largo no Codificante/genética , Proteínas Represoras/genética , Motivo alfa Estéril/genética , Neoplasias Gástricas/metabolismo , Dedos de Zinc/genética , Apoptosis , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Metilación de ADN , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Neoplasias Pulmonares/genética , Serpinas/genética , Serpinas/metabolismo , Neoplasias Gástricas/genética , Activación Transcripcional , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
17.
Int J Biochem Cell Biol ; 61: 53-62, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25681686

RESUMEN

Although expression quantitative trait locus, eQTL, serves as an explicit indicator of gene-gene associations, challenges remain to disentangle the mechanisms by which genetic variations alter gene expression. Here we combined eQTL and molecular analyses to identify an association between two seemingly non-associated genes in brain expression data from BXD inbred mice, namely Ptpn21 and Nrg3. Using biotinylated receptor tracking and immunoprecipitation analyses, we determined that PTPN21 de-phosphorylates the upstream receptor tyrosine kinase ErbB4 leading to the up-regulation of its downstream signaling. Conversely, kinase-dead ErbB4 (K751R) or phosphatase-dead PTPN21 (C1108S) mutants impede PTPN21-dependent signaling. Furthermore, PTPN21 also induced Elk-1 activation in embryonic cortical neurons and a novel Elk-1 binding motif was identified in a region located 1919bp upstream of the NRG3 initiation codon. This enables PTPN21 to promote NRG3 expression through Elk-1, which provides a biochemical mechanism for the PTPN21-NRG3 association identified by eQTL. Biologically, PTPN21 positively influences cortical neuronal survival and, similar to Elk-1, it also enhances neuritic length. Our combined approaches show for the first time, a link between NRG3 and PTPN21 within a signaling cascade. This may explain why these two seemingly unrelated genes have previously been identified as risk genes for schizophrenia.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neuritas/metabolismo , Neuronas/metabolismo , Proteínas Tirosina Fosfatasas no Receptoras/metabolismo , Receptor ErbB-4/metabolismo , Animales , Supervivencia Celular/fisiología , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Células HEK293 , Humanos , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Neurregulinas/biosíntesis , Neurregulinas/genética , Neurregulinas/metabolismo , Neuronas/citología , Proteínas Tirosina Fosfatasas no Receptoras/genética , Sitios de Carácter Cuantitativo , Receptor ErbB-4/genética , Transducción de Señal , Transfección
18.
Clin Ophthalmol ; 9: 187-91, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25678766

RESUMEN

BACKGROUND: Our aim was to describe the demographics, risk factors, clinical signs, severity, and outcome of ocular surface disease (OSD) in 12 patients who had undergone trabeculectomy augmented with mitomycin C (MMC). METHODS: Twelve glaucoma patients were referred to the Dry Eye Clinic (Singapore National Eye Centre) for further management of clinically significant OSD. RESULTS: Of the 15 eyes from 12 patients, 14 were treated with MMC and one with 5-fluorouracil. Mean age was 69.3±10.6 years and two-thirds were male. The median interval before onset of dry eye symptoms after surgery was 13.5 months. Mean tear breakup time (TBUT) was 5.32 seconds and mean Schirmer score was 6.14 mm/5 min. Possible major risk factors for OSD in the cases include limbal stem cell deficiency occurring from exposure to antimetabolites, chronic use of antiglaucoma medications prior to surgery, and the preoperative status of the ocular surface prior to disease onset. Treatment of OSD resulted in improved best corrected visual acuity (BCVA) in 50% of the patients, with a median gain of two-line improvement in BCVA. CONCLUSION: OSD is a clinical problem often overlooked in patients who undergo antimetabolite-augmented filtration surgery. Recognition of the condition and appropriate treatment can improve patient symptoms and reduce health-care burdens on the economy.

19.
J Biomed Mater Res B Appl Biomater ; 103(3): 503-18, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24915784

RESUMEN

Encapsulation of cells in biocompatible polymer matrices represents a powerful tool for cell-based therapies and therapeutic delivery systems. This technology has successfully been used to deliver pancreatic islets to humans for the treatment of Type 1 diabetes. However, the clinical impact of this technology may be improved by reducing the inflammatory response brought on after implantation of capsules in vivo. Within this study a biocompatible polymeric delivery system combining alginate and photo-crosslinked methacrylated glycol chitosan (MGC) was developed. This approach involved encapsulating cells in calcium-alginate beads, coating with MGC and photo-polymerizing using UVA in the presence of photo-initiator (VA-086), resulting in the formation of capsules ∼600 µm in size. Crosslinking of the MGC outer wall allowed control over capsule swelling and improved the capsules overall properties. Capsule characterization demonstrated the stabilizing influence of polymerization and fluorescence imaging showed that the distribution of glycol chitosan is dependent on molecular weight. Good islet viability and insulin release was demonstrated in vitro over the course of a month, and in vivo transplantation of the capsules demonstrated good biocompatibility, particularly when compared with standard alginate/poly-l-ornithine/alginate capsules.


Asunto(s)
Alginatos/química , Materiales Biocompatibles/química , Quitosano/análogos & derivados , Composición de Medicamentos/métodos , Rechazo de Injerto/prevención & control , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos , Metacrilatos/química , Alginatos/aislamiento & purificación , Animales , Cápsulas , Conformación de Carbohidratos , Células Cultivadas , Quitosano/química , Quitosano/inmunología , Quitosano/aislamiento & purificación , Quitosano/efectos de la radiación , Femenino , Reacción a Cuerpo Extraño/prevención & control , Ácido Glucurónico/química , Ácido Glucurónico/inmunología , Ácido Glucurónico/aislamiento & purificación , Ácidos Hexurónicos/química , Ácidos Hexurónicos/inmunología , Ácidos Hexurónicos/aislamiento & purificación , Hidrogeles , Interacciones Hidrofóbicas e Hidrofílicas , Islotes Pancreáticos/metabolismo , Prueba de Limulus , Masculino , Ensayo de Materiales , Metacrilatos/aislamiento & purificación , Metacrilatos/efectos de la radiación , Ratones , Microesferas , Estructura Molecular , Péptidos , Cavidad Peritoneal , Permeabilidad , Polimerizacion/efectos de la radiación , Sus scrofa , Porcinos , Trasplante Heterólogo , Rayos Ultravioleta
20.
Ophthalmology ; 122(3): 494-501, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25444640

RESUMEN

OBJECTIVE: To examine the impact of glaucoma and visual acuity (VA) and visual field (VF) losses on psychosocial functioning (PF). DESIGN: Cross-sectional study. PARTICIPANTS: We compared PF between 192 participants with bilateral glaucoma with VA or VF losses and 40 controls from a tertiary eye hospital clinic in Singapore. METHODS: Glaucoma was defined using the Hodapp-Anderson-Parish criteria. Four psychosocial outcomes of the Glaucoma Quality of Life 36 questionnaire were psychometrically assessed using Rasch analysis. Multivariate regression was performed to determine the independent impact of glaucoma and VA and VF losses on PF. The impact of VA and VF on PF were evaluated by restricted cubic spline analysis. MAIN OUTCOME MEASURES: Anxiety, self-image, psychological well-being, and confidence in health care. RESULTS: The mean age of participants was 66.2±11.0 years, and 63% were male. In the better eye, VA and mean deviation were Snellen 20/25 and -8.89±6.52 dB, respectively. In multivariate models, glaucoma patients had 63.0% greater anxiety (95% confidence interval [CI], -66.0% to -61.2%; P<0.001), 71.0% lower self-image (95% CI, -74.1% to -68.5%; P<0.001), 38.3% less psychological well-being (95% CI, -37.4% to -39.0%; P<0.001), and 32.4% reduced confidence in health care than patients without glaucoma. The worst VA and VF categories had the most reduced PF (range, 26.0% to 81.5%; P<0.001 for all associations) compared with controls. With worsening VA, there was a linear increase in anxiety (P=0.009) and decrease in self-image (P=0.005). With worsening VF from 0 to -12.1 dB (P=0.003), anxiety increased before plateauing. Self-image decreased as VF worsened from 0 to -10 dB (P<0.001), and confidence in health care decreased when VF worsened from 0 to -9.3 dB (P=0.008). However, self-image and confidence in health care actually improved at greater levels of VF loss beyond these thresholds. CONCLUSION: Glaucoma negatively affects PF. Early stage glaucoma with mild VF loss adversely affects anxiety, self-image, and confidence in health care. As VA worsens in advanced glaucoma, anxiety further increases and self-image deteriorates. Ophthalmologists and glaucoma patients need to be aware that both VA and VF losses at different stages of glaucoma negatively impact PF.


Asunto(s)
Ansiedad/psicología , Glaucoma/psicología , Calidad de Vida/psicología , Autoimagen , Trastornos de la Visión/psicología , Agudeza Visual/fisiología , Campos Visuales/fisiología , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Perfil de Impacto de Enfermedad , Singapur , Encuestas y Cuestionarios , Centros de Atención Terciaria
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