Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
1.
Artículo en Inglés | MEDLINE | ID: mdl-39095252

RESUMEN

INTRODUCTION: With advances in therapeutics and longer survival across different cancer spectrums, the incidence of therapy-related acute myeloid leukemia (tAML) has continued to rise. This study aims to evaluate the trend of survival outcomes and their association with sociodemographic factors in tAML over the last 20 years. METHODS: We identified tAML patients between 2000 and 2020 from the Surveillance, Epidemiology, and End Results database. Patients were divided into 4 age groups: 18-39, 40-59, 60-69, and >= 70 years, and 4 diagnostic periods: 2000-2005, 2006-2010, 2011-2015, and 2016-2020. Overall survival (OS) was compared using Kaplan Meier and log-rank methods. RESULTS: The 1-year (and 5-year) OS in patients with tAML was 59.3% (33.7%), 48.2% (24.8%), 37.2% (11.1%), and 32.9% (5.5%) in age groups 18-39, 40-59, 60-69, and >=70 years, respectively. The 1-year (and 5-year) OS based on the year of diagnosis was 20.9% (13.2%), 36.8% (15.2%), 41.9% (13.88%), and 40.4% (not reached) for 2000-2005, 2006-2010, 2011-2015, and 2016-2020 respectively. Among the youngest cohort aged 18-39 years, 1-year OS was 35.7%, 57.7%, 66.7%, and 59.6%, respectively, in 4 diagnostic periods, whereas 1-year OS was 10.5%, 23.9%, 32.2%, and 36.9%, respectively, in the oldest cohort aged >=70 years. Age, year of diagnosis, and geographic location were independent prognostic markers of OS. CONCLUSION: Our study demonstrates a significant improvement in the 1-year OS of tAML patients over the last decade, but the long-term prognosis remains dismal. Older patients continue to show improved survival in recent years with the addition of newer intensive and nonintensive options.

2.
Nat Commun ; 15(1): 7097, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39154007

RESUMEN

Converging evidence indicates that extra-embryonic yolk sac is the source of both macrophages and endothelial cells in adult mouse tissues. Prevailing views are that these embryonically derived cells are maintained after birth by proliferative self-renewal in their differentiated states. Here we identify clonogenic endothelial-macrophage (EndoMac) progenitor cells in the adventitia of embryonic and postnatal mouse aorta, that are independent of Flt3-mediated bone marrow hematopoiesis and derive from an early embryonic CX3CR1+ and CSF1R+ source. These bipotent progenitors are proliferative and vasculogenic, contributing to adventitial neovascularization and formation of perfused blood vessels after transfer into ischemic tissue. We establish a regulatory role for angiotensin II, which enhances their clonogenic and differentiation properties and rapidly stimulates their proliferative expansion in vivo. Our findings demonstrate that embryonically derived EndoMac progenitors participate in local vasculogenic responses in the aortic wall by contributing to the expansion of endothelial cells and macrophages postnatally.


Asunto(s)
Aorta , Macrófagos , Animales , Macrófagos/citología , Macrófagos/metabolismo , Aorta/citología , Ratones , Receptor 1 de Quimiocinas CX3C/metabolismo , Receptor 1 de Quimiocinas CX3C/genética , Células Endoteliales/citología , Células Endoteliales/metabolismo , Diferenciación Celular , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Angiotensina II , Proliferación Celular , Células Madre/citología , Células Madre/metabolismo , Ratones Endogámicos C57BL , Femenino , Neovascularización Fisiológica , Receptores de Quimiocina/metabolismo , Receptores de Quimiocina/genética , Masculino , Hematopoyesis/fisiología , Tirosina Quinasa 3 Similar a fms
3.
Sci Rep ; 13(1): 11017, 2023 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-37419942

RESUMEN

Nanophthalmos is characterised by shorter posterior and anterior segments of the eye, with a predisposition towards high hyperopia and primary angle-closure glaucoma. Variants in TMEM98 have been associated with autosomal dominant nanophthalmos in multiple kindreds, but definitive evidence for causation has been limited. Here we used CRISPR/Cas9 mutagenesis to recreate the human nanophthalmos-associated TMEM98 p.(Ala193Pro) variant in mice. The p.(Ala193Pro) variant was associated with ocular phenotypes in both mice and humans, with dominant inheritance in humans and recessive inheritance in mice. Unlike their human counterparts, p.(Ala193Pro) homozygous mutant mice had normal axial length, normal intraocular pressure, and structurally normal scleral collagen. However, in both homozygous mice and heterozygous humans, the p.(Ala193Pro) variant was associated with discrete white spots throughout the retinal fundus, with corresponding retinal folds on histology. This direct comparison of a TMEM98 variant in mouse and human suggests that certain nanophthalmos-associated phenotypes are not only a consequence of a smaller eye, but that TMEM98 may itself play a primary role in retinal and scleral structure and integrity.


Asunto(s)
Glaucoma de Ángulo Cerrado , Hiperopía , Proteínas de la Membrana , Microftalmía , Animales , Humanos , Ratones , Fondo de Ojo , Glaucoma de Ángulo Cerrado/patología , Hiperopía/genética , Hiperopía/complicaciones , Proteínas de la Membrana/genética , Microftalmía/genética , Microftalmía/patología , Fenotipo
4.
Appl Water Sci ; 12(6): 115, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35441072

RESUMEN

Rivers are the lifeline of every living being, be it humans or animals. Clean water is essential for everyone. However, increased urbanization and rapid industrialization have led to rising pollution level in rivers. COVID-19 on the contrary has changed the entire ecosystem. Limited industrial activities, reduced people movement during COVID times has led to improvement in environment, be it atmosphere or hydrosphere. Present work aims to study the impact of COVID-19 on water quality index of river Yamuna as it traverses from Himalayan segment to Upper segment. Five sites are chosen between a stretch of 60+ km, and samples are collected during monsoon and post-monsoon seasons. Physico-chemical parameters (pH, Turbidity, Sulphate, Phosphate, Fluoride, Chloride, Total Hardness, Calcium, Magnesium, Dissolved Oxygen, BOD, COD, Alkalinity), water quality index and Pearson correlation coefficient were calculated for all chosen sites. Since the study was initiated during COVID, initial results show the impact of reduced industrial and urban activities in improving the overall water quality.

5.
Invest Ophthalmol Vis Sci ; 63(3): 26, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-35348588

RESUMEN

Purpose: Pseudoexfoliation syndrome (PEX) is a common systemic disease that results in severe and often irreversible vision loss. Despite considerable research effort, PEX remains incompletely understood. This study sought to perform the first RNAseq study in elucidate the pathophysiology of PEX, and contribute a publicly available transcriptomic data resource for future research. Methods: Human ocular lens capsular epithelium samples were collected from 25 patients with PEX and 39 non-PEX controls undergoing cataract surgery. RNA extracted from these specimens was subjected to polyadenylated (mRNA) selection and deep bulk RNA sequencing. Differential expression analysis investigated protein-coding gene transcripts. Exploratory analyses used pathway analysis tools, and curated class- and disease-specific gene sets. Results: Differential expression analysis demonstrated that 2882 genes were differentially expressed according to PEX status. Genes associated with viral gene expression pathways were among the most upregulated, alongside genes encoding ribosomal and mitochondrial respiratory transport chain proteins. Cell adhesion protein transcripts including type 4 collagen subunits were downregulated. Conclusions: This comparative transcriptomic dataset highlights novel and previously recognized pathogenic pathways in PEX and provides the first comprehensive transcriptomic resource, adding an additional layer to build further understanding of PEX pathophysiology.


Asunto(s)
Extracción de Catarata , Síndrome de Exfoliación , Cristalino , Epitelio/metabolismo , Síndrome de Exfoliación/genética , Síndrome de Exfoliación/patología , Humanos , Cristalino/metabolismo , Análisis de Secuencia de ARN
6.
J Lab Physicians ; 13(3): 202-207, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34602782

RESUMEN

Objective An ambulance is a medically equipped vehicle which is used in case of any medical emergency for the transport of patients to treatment facilities. The ambulances help in the transportation of thousands of patients per year, and such patients may carry infectious microorganisms which pose a major threat to the treatment of such patients. In this study, we analyzed the extent of bacterial contamination in our ambulance vehicles and measured the degree of antimicrobial resistance among isolated pathogens. Material and Method This study included five ambulances of our tertiary care hospital and different random sites were swabbed in each vehicle. These were selected based on their well-known high frequency of contact by emergency personnel and patients. Swabs were inserted into sterile test tubes containing normal saline and immediately transferred to our microbiology laboratory to identify bacterial contaminants utilizing standard microbiological procedures. Result A total of 198 swab samples were collected from all the five ambulances, out of which 170 (85.8%) swabs were sterile and 28 (14.2%) swabs yielded potentially pathogenic bacterial isolates. The highest contamination rate with pathogenic bacteria was detected in the oxygen flow meter knob (60%), suction machine tubing (60%), and stethoscope (40%). Staphylococcus aureus (32%) was the most frequently detected microorganism. Conclusion Our study showed low prevalence of bacterial contamination in ambulances because of good infection control policy of our hospital, however, some areas still need improvement and require proper standard operating procedures of disinfection policies of these emergency vehicles.

7.
Invest Ophthalmol Vis Sci ; 62(12): 3, 2021 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-34495288

RESUMEN

Purpose: Age-related cataract is the leading cause of blindness worldwide. Variants in the EPHA2 gene increase the disease risk, and its knockout in mice causes cataract. We investigated whether age, sex, and genetic background, risk factors for age-related cataract, and Epha2 genotype influence Epha2-related cataract development in mice. Methods: Cataract development was monitored in Epha2+/+, Epha2+/-, and Epha2-/- mice (Epha2Gt(KST085)Byg) on C57BL/6J and FVB:C57BL/6J (50:50) backgrounds. Cellular architecture of lenses, endoplasmic reticulum (ER) stress, and redox state were determined using histological, molecular, and analytical techniques. Results: Epha2-/- and Epha2+/- mice on C57BL/6J background developed severe cortical cataracts by 18 and 38 weeks of age, respectively, compared to development of similar cataract significantly later in Epha2-/- mice and no cataract in Epha2+/- mice in this strain on FVB background, which was previously reported. On FVB:C57BL/6J background, Epha2-/- mice developed severe cortical cataract by 38 weeks and Epha2+/- mice exhibited mild cortical cataract up to 64 weeks of age. Progression of cataract in Epha2-/- and Epha2+/- female mice on C57BL/6J and mixed background, respectively, was slower than in matched male mice. N-cadherin and ß-catenin immunolabeling showed disorganized lens fiber cells and disruption of lens architecture in Epha2-/- and Epha2+/- lenses, coinciding with development of severe cataracts. EPHA2 immunolabeling showed intracellular accumulation of the mutant EPHA2-ß-galactosidase fusion protein that induced a cytoprotective ER stress response and in Epha2+/- lenses was also accompanied by glutathione redox imbalance. Conclusions: Both, Epha2-/- and Epha2+/- mice develop age-related cortical cataract; age as a function of Epha2 genotype, sex, and genetic background influence Epha2-related cataractogenesis in mice.


Asunto(s)
Catarata/genética , Regulación de la Expresión Génica , Cristalino/metabolismo , ARN/genética , Receptor EphA2/genética , Animales , Catarata/diagnóstico , Catarata/metabolismo , Modelos Animales de Enfermedad , Genotipo , Cristalino/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor EphA2/biosíntesis
8.
Exp Eye Res ; 210: 108692, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34228965

RESUMEN

Fuchs' endothelial corneal dystrophy (FECD) is a progressive vision impairing disease caused by thickening of Descemet's membrane and gradual degeneration and loss of corneal endothelial cells. The aim of this study was to identify differentially expressed genes between FECD-affected and unaffected corneal endothelium to gain insight into the pathophysiological mechanisms underlying this disease. Microarray gene expression analysis was performed on total RNA from FECD-affected and unaffected corneal endothelium-Descemet's membrane (CE-DM) specimens using the Illumina HumanHT-12 v4.0 expression array. RNA from pools of FECD-affected (n = 3 per pool) and individual unaffected (n = 3) specimens was used for comparison. Altered expression of a sub-set of differentially expressed genes was validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in independent specimens. Bioinformatics analysis was performed using InnateDB to reveal functional relationships among the differentially expressed genes and molecular pathways involved in the disease. A total of 16,513 genes were found expressed in the corneal endothelium of which 142 genes were differentially expressed between FECD-affected and unaffected endothelium (log2 fold-change ≥1.5, corrected p-value ≤0.05). Most of the genes were up-regulated (126) and a small proportion down-regulated (16) in affected corneal endothelium. Of the twelve genes prioritised for validation, differential expression of 10 genes, including those ranked 57th and 81st by significance validated by qRT-PCR (8 up-regulated and 2 downregulated, corrected p ≤ 0.05), one gene showed a trend for up-regulation in affected endothelium, consistent with the microarray analysis and another was up-regulated in an independent study indicating robustness of the differential expression dataset. Bioinformatic analysis revealed significant over-representation of differentially expressed genes in extracellular matrix reorganisation, cellular remodelling, immune response, and inflammation. Network analysis showed functional inter-relatedness of the majority of the dysregulated genes and revealed known direct functional relationships between 20 of the genes; many of these genes have roles in macrophage differentiation, phagocytosis and inflammation. This is the second report of microarray gene expression analysis in FECD. This study revealed a set of highly dysregulated genes in the corneal endothelium in FECD. More than a third of the dysregulated genes in the disease have been discovered for the first time and thus are novel. The dysregulated genes strongly suggest the presence of phagocytic cells, most likely immune cells, and inflammation in corneal endothelium in the disease. This study provides a molecular framework for delineating the mechanisms underlying these cellular processes in FECD.


Asunto(s)
Endotelio Corneal/metabolismo , Proteínas del Ojo/genética , Distrofia Endotelial de Fuchs/genética , Regulación de la Expresión Génica/fisiología , Fagocitos/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Células Cultivadas , Femenino , Distrofia Endotelial de Fuchs/fisiopatología , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis por Matrices de Proteínas , ARN/genética , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
9.
Infect Disord Drug Targets ; 21(7): e300821191666, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33618650

RESUMEN

BACKGROUND: Serratia spp. is a common enteric bacterium generally thought not to be pathogenic in the gastrointestinal tract. Serratia marcescens is a member of the genus Serratia, which is a part of the family Enterobacteriales. Of all Serratia species, S. marcescens is the most common clinical isolate and the most important human pathogen. OBJECTIVE: We discuss here four cases of Serratia marcescens which were reported in our laboratory at the Department of Microbiology Government Medical College and Hospital Chandigarh within six months of duration. METHOD: All the samples were processed and identified using standard microbiological techniques. The isolates of Serratia marcescens were identified, depending upon their biochemical and morphological characteristics, and further confirmed by MALDI-TOF-MS, PGIMER Chandigarh. RESULT: In one of the four cases, polymicrobial infection was observed, and among the cases, one patient was diabetic and the rest three patients were immunocompetent. The importance of detection of Serratia marcescens is related to the concern regarding its increased spread in hospital settings as nosocomial infection. CONCLUSION: We need to identify and isolate this pathogen not thinking of it only as a contaminant and opportunistic pathogen but as a pathogen which can lead to serious infections in hospital settings.


Asunto(s)
Infección Hospitalaria , Infecciones por Serratia , Humanos , Serratia , Serratia marcescens , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
10.
Infect Disord Drug Targets ; 21(2): 238-242, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32516105

RESUMEN

OBJECTIVE: Source of infection in a burn patient is from the patient's flora, contaminated environmental surfaces and transmitted from health care workers. Insufficiently disinfected hospital environmental surface provides a niche for multidrug resistant bacteria. This study was carried out to assess the bacteriological profile of the pathogens from burn wounds and the surrounding environmental areas. METHODS: During 6 months, wound swabs from burn patients were collected on admission (after 48 hours of admission), on day 5 and then weekly. Environmental samples were also collected from burn ward and studied for the bacteriological and anti-microgram profiles. RESULTS: Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii were the major bacterial isolates from the wound swabs and the environmental samples. ESBL was detected in 56.6% of our Enterobacteriaceae isolates. The environmental sites from which these bacterial isolates were found were nursing counter, sink, dressing trolley, medicine locker and patient's bed. The percentage of MRSA decreased from 50 to 5% and there was an increased role of Enterococci species causing infections (13.63%). CONCLUSION: In this study, there appears that the colonizers of the environment may play a role in the causation of infection in burn patients. In burns ward, rigorous implementation of infection control program should be warranted, which includes and hygiene and use of personal protective equipment, environmental disinfection, cohort nursing care and antibiotics stewardship programme.


Asunto(s)
Acinetobacter baumannii , Quemaduras , Centros de Atención Terciaria , Antibacterianos , Infección Hospitalaria , Humanos , India , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa
11.
Infect Disord Drug Targets ; 21(1): 84-89, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-31994472

RESUMEN

INTRODUCTION: The members of the tribe Proteeae, Morganella and Providencia are being increasingly recognized as important pathogens. The spectrum of disease caused by them is wide and in reported cases, the mortality is high. Previously both of these pathogens were considered to be rare pathogens as the potential to cause nosocomial transmission and infection was not much studied. But their phenomenal evolution and increase in multidrug-resistance (MDR) strains of these pathogens are posing a major threat toward public health throughout the world. METHODS: This present study was carried out from July 2018 to December 2018 on all the pus and body fluid samples that were received in the Department of Microbiology. Samples were processed as per the standard Microbiological guidelines and also were analyzed for their antimicrobial susceptibility profile as per Clinical Laboratory Standards Institute. RESULTS: Out of 8425 samples received, 2140 were culture positive, amongst which 19 samples (0.89%) were positive for Providencia species (9) and Morganella morganii(10). The male : female ratio of these 19 patients was 2.8 : 1 and maximum patients (13) belonged to 20-60 years. As far as risk factors are concerned, maximum patients were diabetics (7) followed by abnormal liver function tests (6), concomitant UTI (6), history of invasive procedure (5), prior exposure to antibiotics (5) and urinary catheterization (4). About 6 were polymicrobial infections. Antibiotic susceptibility patterns revealed that Providencia strains were sensitive to ampicillin- sulbactum (77.7%) and amikacin (77.7%), while all Morganella strains were 100% sensitive to tobramycin and piperacillintazobactam. CONCLUSION: This study heralds in need for more research in this area as infections caused by these two pathogens are on the rise. Moreover, resistance to antimicrobials is also an increasingly common problem thus delaying the treatment and prognosis of the disease.


Asunto(s)
Morganella morganii , Providencia , Antibacterianos/uso terapéutico , Femenino , Humanos , India , Masculino , Pruebas de Sensibilidad Microbiana , Centros de Atención Terciaria
12.
Invest Ophthalmol Vis Sci ; 61(5): 48, 2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-32460312

RESUMEN

Purpose: Ultraviolet radiation from sunlight contributes to age-related cataract and skin cancer. The EPHA2 gene is implicated in both these diseases. The purpose of this study was to determine whether age-related cataract and skin cancer are associated in a cohort of older Australians. Methods: A cross-sectional study was performed using the Historical Cohort of the Registry of Senior Australians. Individuals aged ≥65 years or aged ≥50 years and of Aboriginal or Torres Strait Islander descent, who had an aged care eligibility assessment between July 2005 and June 2015, and had a history of cataract surgery and/or skin cancer according to the Australian Government Medicare Benefits Schedule dataset, during the 3-year period prior, were evaluated (N = 599,316). A multivariable logistic regression model was used to determine association and multiple hypothesis correction was employed. Results: Of the evaluated individuals, 87,097 (14.5%) had a history of cataract and 170,251 (28.4%) a history of skin cancer. Among those with a history of cataract, 20,497 (23.5%), 1127 (1.3%), and 14,730 (16.9%) individuals had a concurrent history of keratinocyte, melanoma, and premalignant/solar keratosis, respectively. Those with a history of cataract were 19% more likely to have a history of skin cancer (odds ratio [OR], 1.19; 95% confidence interval [CI], (1.17-1.21). Co-occurrence of keratinocyte skin cancer was 16% (OR, 1.16; 95% CI, 1.14-1.18), melanoma 21% (OR, 1.21; 95% CI, 1.13-1.29), and premalignant/solar keratosis 19% (OR, 1.19; 95% CI, 1.17-1.22) more in the presence than absence of history of cataract. Conclusions: Age-related cataract is positively associated with skin cancer and its subtypes, including premalignant lesions in an older Australian population.


Asunto(s)
Catarata/complicaciones , Catarata/epidemiología , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino
13.
Infect Disord Drug Targets ; 20(5): 713-717, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31389316

RESUMEN

BACKGROUND: Coagulase negative Staphylococci (CoNS) are important. The common antibiotics used for the treatment of the infections caused by CoNS are penicillin, oxacillin, ciprofloxacin, clindamycin, erythromycin, gentamicin, and vancomycin. Linezolid is an oxazolidinone group of antibiotic with activity against Gram-positive bacteria. It is used for the treatment of serious infections caused by Gram-positive bacteria resistant to other antibiotics, including streptococci, vancomycin-resistant enterococci (VRE). AIMS AND OBJECTIVE: This study emphasizes on the judicious use of newer antibiotics to contain the spread of resistance. METHOD: We are discussing five cases of Linezolid resistant Staphylococcus Haemolyticus which were reported in our laboratory during one year from patients with device related infections and also review of literature is being presented for an update. RESULT: In our study, the isolates were resistant to other groups of antimicrobials but susceptible to glycopeptides. All the isolates were methicillin-resistant. CONCLUSION: Linezolid is approved as an alternative drug to be given for catheter-related bloodstream infections. In earlier studies, linezolid-resistant staphylococci have been reported increasingly all over the world. This study is to create awareness amongst clinicians that improper and excessive use of linezolid will make this antibiotic-resistant and thus will be of no help in future, so judicious and relevant use of antibiotics needs to be emphasized.


Asunto(s)
Farmacorresistencia Bacteriana/efectos de los fármacos , Equipos y Suministros/microbiología , Glicopéptidos/farmacología , Infecciones Estafilocócicas/microbiología , Staphylococcus haemolyticus/efectos de los fármacos , Adulto , Anciano , Femenino , Glicopéptidos/uso terapéutico , Humanos , Linezolid/farmacología , Masculino , Resistencia a la Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus haemolyticus/aislamiento & purificación , Resultado del Tratamiento , Adulto Joven
14.
Exp Eye Res ; 188: 107806, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31539542

RESUMEN

Age-related cataract is the major cause of blindness worldwide. Both genetic and environmental factors contribute to the disease. Genetic variation in the Ephrin type-A receptor 2 (EPHA2) gene is associated with the risk of age-related cataract in multiple populations, and exposure to ultraviolet-B (UV-B) radiation is a well-established risk factor for the disease. Epha2 knockout and UV-B radiation independently lead to cataract in mice, and UV-B radiation reportedly alters EPHA2 expression in cultured cells. We hypothesised that an interaction between UV-B radiation exposure and Epha2 signalling may influence cataract development. To test this hypothesis, 5-week-old Epha2+/+ and Epha2+/- mice (n = 8 per group) were exposed to repeated below-threshold doses of UV-B radiation (0.0125-0.05 J/cm2), before development of Epha2-mediated cataract. Cataract development was monitored after termination of exposure and at least one month later. Histological analysis of exposed and unexposed lenses was performed to assess pathological changes, and gene expression analysis to investigate the mechanism underlying cataract. Both Epha2+/+ and Epha2+/- mice developed UV-B dose-dependent anterior polar cataract; cataract severity in both genotypes of mice exposed to either 0.025 or 0.05 J/cm2 UV-B was significantly higher than that in matched unexposed mice (p < 0.05). Histological analysis of lenses of both genotypes of mice exposed to 0.025 or 0.05 J/cm2 UV-B radiation consistently revealed disruption of the lens architecture. A month after the exposure, cataract severity increased in Epha2+/+ mice treated with the highest dose of UV-B radiation (p = 0.03) but remained unchanged in Epha2+/- mice. Gene expression analysis of lenses of both genotypes of mice showed significant upregulation of the cell proliferation marker Mki67 in Epha2+/+ (p = 0.036) but not in Epha2+/- mice exposed to the highest dose of UV-B radiation compared to matched unexposed mice. In conclusion, this study suggests that repeated exposure to doses of UV-B radiation lower than the single minimum dose required for inducing cataract leads to cataract in wild-type and Epha2 heterozygous knockout mice. Furthermore, this study indicates, for the first time, a potentially favourable effect of partial Epha2 deficiency against UV radiation-induced damage in the lens.


Asunto(s)
Catarata/genética , Interacción Gen-Ambiente , Cristalino/efectos de la radiación , Traumatismos Experimentales por Radiación/genética , Receptor EphA2/genética , Rayos Ultravioleta/efectos adversos , Animales , Catarata/patología , Relación Dosis-Respuesta en la Radiación , Proteínas del Ojo/genética , Regulación de la Expresión Génica/fisiología , Genotipo , Técnicas de Genotipaje , Cristalino/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Dosis de Radiación , Traumatismos Experimentales por Radiación/patología , Reacción en Cadena en Tiempo Real de la Polimerasa
15.
Clin Exp Ophthalmol ; 47(8): 1028-1042, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31206232

RESUMEN

BACKGROUND: Fuchs endothelial corneal dystrophy (FECD) is a progressive and potentially a sight threatening disease, and a common indication for corneal grafting in the elderly. Aberrant thickening of Descemet's membrane, formation of microscopic excrescences (guttae) and gradual loss of corneal endothelial cells are the hallmarks of the disease. The aim of this study was to identify differentially abundant proteins between FECD-affected and unaffected Descemet's membrane. METHODS: Label-free quantitative proteomics using nanoscale ultra-performance liquid chromatography-mass spectrometry (nUPLC-MSE ) was employed on affected and unaffected Descemet's membrane extracts, and interesting findings were further investigated using quantitative reverse transcription-polymerase chain reaction and immunohistochemical techniques. RESULTS: Quantitative proteomics revealed significantly lower abundance of apolipoprotein E (APOE) and immunoglobulin heavy constant gamma 1 protein (IGHG1) in affected Descemet's membrane. The difference in the distribution of APOE between affected and unaffected Descemet's membrane and of IGHG1 detected by immunohistochemistry support their down-regulation in the disease. Comparative gene expression analysis showed significantly lower APOE mRNA levels in FECD-affected than unaffected corneal endothelium. IGHG1 gene is expressed at extremely low levels in the corneal endothelium, precluding relative expression analysis. CONCLUSIONS: This is the first study to report comparative proteomics of Descemet's membrane tissue, and implicates dysregulation of APOE and IGHG1 proteins in the pathogenesis of Fuchs endothelial corneal dystrophy.


Asunto(s)
Apolipoproteínas E/genética , Proteínas Portadoras/genética , Distrofia Endotelial de Fuchs/genética , Regulación de la Expresión Génica/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Apolipoproteínas E/metabolismo , Proteínas Portadoras/metabolismo , Cromatografía Líquida de Alta Presión , Femenino , Distrofia Endotelial de Fuchs/metabolismo , Humanos , Inmunohistoquímica , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Proteómica , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
16.
Nat Genet ; 50(8): 1067-1071, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30054594

RESUMEN

Intraocular pressure (IOP) is currently the sole modifiable risk factor for primary open-angle glaucoma (POAG), one of the leading causes of blindness worldwide1. Both IOP and POAG are highly heritable2. We report a combined analysis of participants from the UK Biobank (n = 103,914) and previously published data from the International Glaucoma Genetic Consortium (n = 29,578)3,4 that identified 101 statistically independent genome-wide-significant SNPs for IOP, 85 of which have not been previously reported4-12. We examined these SNPs in 11,018 glaucoma cases and 126,069 controls, and 53 SNPs showed evidence of association. Gene-based tests implicated an additional 22 independent genes associated with IOP. We derived an allele score based on the IOP loci and loci influencing optic nerve head morphology. In 1,734 people with advanced glaucoma and 2,938 controls, participants in the top decile of the allele score were at increased risk (odds ratio (OR) = 5.6; 95% confidence interval (CI): 4.1-7.6) of glaucoma relative to the bottom decile.


Asunto(s)
Glaucoma/genética , Presión Intraocular/genética , Femenino , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Humanos , Masculino , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo
17.
Artículo en Inglés | MEDLINE | ID: mdl-29770612

RESUMEN

BACKGROUND: Pediatric cataract is an important cause of blindness and visual impairment in children. A large proportion of pediatric cataracts are inherited, and many genes have been described for this heterogeneous Mendelian disease. Surveys of schools for the blind in Bhutan, Cambodia, and Sri Lanka have identified many children with this condition and we aimed to identify the genetic causes of inherited cataract in these populations. METHODS: We screened, in parallel, 51 causative genes for inherited cataracts in 33 probands by Ampliseq enrichment and sequencing on an Ion Torrent PGM. Rare novel protein coding variants were assessed for segregation in family members, where possible, by Sanger sequencing. RESULTS: We identified 24 rare (frequency <1% in public databases) or novel protein coding variants in 12 probands and confirmed segregation of variants with disease in the extended family where possible. Of these, six are predicted to be the cause of disease in the patient, with four other variants also highly likely to be pathogenic. CONCLUSION: This study found that 20%-30% of patients in these countries have a mutation in a known cataract causing gene, which is considerably lower than the 60%-70% reported in Caucasian cohorts. This suggests that additional cataract genes remain to be discovered in this cohort of Asian pediatric cataract patients.

18.
Sci Rep ; 8(1): 3124, 2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29449654

RESUMEN

Open-angle glaucoma (OAG) is a major cause of blindness worldwide. To identify new risk loci for OAG, we performed a genome-wide association study in 3,071 OAG cases and 6,750 unscreened controls, and meta-analysed the results with GWAS data for intraocular pressure (IOP) and optic disc parameters (the overall meta-analysis sample size varying between 32,000 to 48,000 participants), which are glaucoma-related traits. We identified and independently validated four novel genome-wide significant associations within or near MYOF and CYP26A1, LINC02052 and CRYGS, LMX1B, and LMO7 using single variant tests, one additional locus (C9) using gene-based tests, and two genetic pathways - "response to fluid shear stress" and "abnormal retina morphology" - in pathway-based tests. Interestingly, some of the new risk loci contribute to risk of other genetically-correlated eye diseases including myopia and age-related macular degeneration. To our knowledge, this study is the first integrative study to combine genetic data from OAG and its correlated traits to identify new risk variants and genetic pathways, highlighting the future potential of combining genetic data from genetically-correlated eye traits for the purpose of gene discovery and mapping.


Asunto(s)
Glaucoma de Ángulo Abierto/etiología , Glaucoma de Ángulo Abierto/genética , Anciano , Proteínas de Unión al Calcio/genética , Estudios de Casos y Controles , Endofenotipos , Femenino , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Genotipo , Glaucoma/etiología , Glaucoma/genética , Glaucoma de Ángulo Abierto/metabolismo , Humanos , Presión Intraocular/genética , Proteínas con Dominio LIM/genética , Proteínas con Homeodominio LIM/genética , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Proteínas Musculares/genética , Disco Óptico/fisiología , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Ácido Retinoico 4-Hidroxilasa/genética , Factores de Riesgo , Tonometría Ocular/métodos , Factores de Transcripción/genética , Campos Visuales/genética , gamma-Cristalinas/genética
19.
Mol Vis ; 24: 801-817, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30713420

RESUMEN

Purpose: Pseudoexfoliation (PEX) syndrome is an age-related progressive disease of the extracellular matrix with ocular manifestations. PEX is clinically diagnosed by the presence of extracellular exfoliative deposits on the anterior surface of the ocular lens. PEX syndrome is a major risk factor for developing glaucoma, the leading cause of irreversible blindness in the world, and is often associated with the development of cataract. PEX reportedly coexists with Alzheimer disease and increases the risk of heart disease and stroke. PEX material deposited on the anterior surface of the ocular lens is highly proteinaceous, complex, and insoluble, making deciphering the protein composition of the material challenging. Thus, to date, only a small proportion of the protein composition of PEX material is known. The aim of this study was to decipher the protein composition of pathological PEX material deposited on the ocular lens in patients and advance the understanding of pathophysiology of PEX syndrome. Methods: Liquid-chromatography and tandem mass spectrometry (LC-MS/MS) was employed to discover novel proteins in extracts of neat PEX material surgically isolated from patients (n = 4) with PEX syndrome undergoing cataract surgery. A sub-set of the identified proteins was validated with immunohistochemistry using lens capsule specimens from independent patients (n=3); lens capsules from patients with cataract but without PEX syndrome were used as controls (n=4). Expression of transcripts of the validated proteins in the human lens epithelium was analyzed with reverse transcription PCR (RT-PCR). Functional relationships among the proteins identified in this study and genes and proteins previously implicated in the disease were bioinformatically determined using InnateDB. Results: Peptides corresponding to 66 proteins, including ten proteins previously known to be present in PEX material, were identified. Thirteen newly identified proteins were chosen for validation. Of those proteins, 12 were found to be genuine components of the material. The novel protein constituents include apolipoproteins (APOA1 and APOA4), stress response proteins (CRYAA and PRDX2), and blood-related proteins (fibrinogen and hemoglobin subunits), including iron-free hemoglobin. The gene expression data suggest that the identified stress-response proteins and hemoglobin are contributed by the lens epithelium and apolipoproteins and fibrinogen by the aqueous humor to the PEX material. Pathway analysis of the identified novel protein constituents and genes or proteins previously implicated in the disease reiterated the involvement of extracellular matrix organization and degradation, elastic fiber formation, and complement cascade in PEX syndrome. Network analysis suggested a central role of fibronectin in the pathophysiology of the disease. The identified novel protein constituents of PEX material also shed light on the molecular basis of the association of PEX syndrome with heart disease, stroke, and Alzheimer disease. Conclusions: This study expands the understanding of the protein composition of pathological PEX material deposited on the ocular lens in patients with PEX syndrome and provides useful insights into the pathophysiology of this disease. This study together with the previous study by our group (Sharma et al. Experimental Eye Research 2009;89(4):479-85) demonstrate that using neat PEX material, devoid of the underlying lens capsule, for proteomics analysis is an effective approach for deciphering the protein composition of complex and highly insoluble extracellular pathological ocular deposits present in patients with PEX syndrome.


Asunto(s)
Catarata/metabolismo , Síndrome de Exfoliación/metabolismo , Cápsula del Cristalino/química , Agregado de Proteínas , Agregación Patológica de Proteínas/metabolismo , Anciano , Anciano de 80 o más Años , Apolipoproteína A-I/química , Apolipoproteína A-I/genética , Apolipoproteína A-I/metabolismo , Apolipoproteínas A/química , Apolipoproteínas A/genética , Apolipoproteínas A/metabolismo , Catarata/genética , Catarata/patología , Cristalinas/química , Cristalinas/genética , Cristalinas/metabolismo , Tejido Elástico/química , Tejido Elástico/metabolismo , Tejido Elástico/patología , Síndrome de Exfoliación/genética , Síndrome de Exfoliación/patología , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Matriz Extracelular/patología , Femenino , Fibrinógeno/química , Fibrinógeno/genética , Fibrinógeno/metabolismo , Expresión Génica , Hemoglobinas/química , Hemoglobinas/genética , Hemoglobinas/metabolismo , Humanos , Cápsula del Cristalino/metabolismo , Cápsula del Cristalino/patología , Masculino , Peroxirredoxinas/química , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Agregación Patológica de Proteínas/genética , Agregación Patológica de Proteínas/patología , Espectrometría de Masas en Tándem
20.
Ophthalmic Genet ; 39(2): 221-227, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29265947

RESUMEN

PURPOSE: Recent genome-wide association studies reported strong association of genetic variation at the CDKN2B/CDKN2B-AS1 locus on 9p21 with normal-tension glaucoma (NTG) in multiple populations. The mechanism by which this locus causes disease remains to be elucidated. We investigated the association of DNA methylation of CpG islands at this locus with NTG. METHODS: We conducted a retrospective case-control study of 178 NTG cases and 202 unaffected controls from Australia. CDKN2B and CDKN2B-AS1 promoter methylation was measured quantitatively using the MassCleave assay, and assessed for association with the disease, and the genotype of the associated risk variants using IBM SPSS statistics 22.0 CpG sites at which methylation status was associated with NTG were validated using pyrosequencing. RESULTS: We identified one CpG site (F1:13-14) in the CDKN2B promoter which showed significant association with NTG (p = 0.001). The association was highly significant in female cases (p = 0.006) but not in male cases (p = 0.054). The association was validated using an independent method confirming the likely association of DNA methylation with NTG in females (p = 0.015), but not in males (p = 0.497). In addition, methylation at CpG sites in CDKN2B was also associated with genotype at rs1063192, which is known to confer risk for NTG. CONCLUSION: This study reveals an association of methylation status in the CDKN2B promoter with NTG, particularly in females. This suggests that the observed genetic association with the disease at this locus could be in part due to epigenetic mechanisms, and is likely to be independent of the association of nonsynonymous coding variation within the gene.


Asunto(s)
Cromosomas Humanos Par 9/genética , Islas de CpG/genética , Inhibidor p15 de las Quinasas Dependientes de la Ciclina/genética , Metilación de ADN , Glaucoma de Baja Tensión/genética , ARN Largo no Codificante/genética , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Epigenómica , Femenino , Predisposición Genética a la Enfermedad , Humanos , Presión Intraocular , Masculino , Regiones Promotoras Genéticas/genética , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA