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1.
Mol Cell ; 71(6): 1012-1026.e3, 2018 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-30174293

RESUMEN

Pre-mRNA splicing is an essential step in the expression of most human genes. Mutations at the 5' splice site (5'ss) frequently cause defective splicing and disease due to interference with the initial recognition of the exon-intron boundary by U1 small nuclear ribonucleoprotein (snRNP), a component of the spliceosome. Here, we use a massively parallel splicing assay (MPSA) in human cells to quantify the activity of all 32,768 unique 5'ss sequences (NNN/GYNNNN) in three different gene contexts. Our results reveal that although splicing efficiency is mostly governed by the 5'ss sequence, there are substantial differences in this efficiency across gene contexts. Among other uses, these MPSA measurements facilitate the prediction of 5'ss sequence variants that are likely to cause aberrant splicing. This approach provides a framework to assess potential pathogenic variants in the human genome and streamline the development of splicing-corrective therapies.


Asunto(s)
Empalme Alternativo/genética , Sitios de Empalme de ARN/genética , Sitios de Empalme de ARN/fisiología , Empalme Alternativo/fisiología , Proteínas Portadoras/genética , Secuencia Conservada/genética , Exones , Genes BRCA2 , Células HeLa , Humanos , Intrones , Mutación , Empalme del ARN/genética , Empalme del ARN/fisiología , ARN Nuclear Pequeño/fisiología , Ribonucleoproteína Nuclear Pequeña U1/fisiología , Empalmosomas , Proteína 1 para la Supervivencia de la Neurona Motora/genética , Factores de Elongación Transcripcional
2.
Proc Natl Acad Sci U S A ; 119(39): e2204233119, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36129941

RESUMEN

Contemporary high-throughput mutagenesis experiments are providing an increasingly detailed view of the complex patterns of genetic interaction that occur between multiple mutations within a single protein or regulatory element. By simultaneously measuring the effects of thousands of combinations of mutations, these experiments have revealed that the genotype-phenotype relationship typically reflects not only genetic interactions between pairs of sites but also higher-order interactions among larger numbers of sites. However, modeling and understanding these higher-order interactions remains challenging. Here we present a method for reconstructing sequence-to-function mappings from partially observed data that can accommodate all orders of genetic interaction. The main idea is to make predictions for unobserved genotypes that match the type and extent of epistasis found in the observed data. This information on the type and extent of epistasis can be extracted by considering how phenotypic correlations change as a function of mutational distance, which is equivalent to estimating the fraction of phenotypic variance due to each order of genetic interaction (additive, pairwise, three-way, etc.). Using these estimated variance components, we then define an empirical Bayes prior that in expectation matches the observed pattern of epistasis and reconstruct the genotype-phenotype mapping by conducting Gaussian process regression under this prior. To demonstrate the power of this approach, we present an application to the antibody-binding domain GB1 and also provide a detailed exploration of a dataset consisting of high-throughput measurements for the splicing efficiency of human pre-mRNA [Formula: see text] splice sites, for which we also validate our model predictions via additional low-throughput experiments.


Asunto(s)
Epistasis Genética , Precursores del ARN , Teorema de Bayes , Mapeo Cromosómico , Biología Computacional , Genotipo , Humanos , Modelos Genéticos , Mutación , Fenotipo , Empalme del ARN
3.
J Biol Chem ; 296: 100192, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33334889

RESUMEN

Histone methylation is central to the regulation of eukaryotic transcription. In Saccharomyces cerevisiae, it is controlled by a system of four methyltransferases (Set1p, Set2p, Set5p, and Dot1p) and four demethylases (Jhd1p, Jhd2p, Rph1p, and Gis1p). While the histone targets for these enzymes are well characterized, the connection of the enzymes with the intracellular signaling network and thus their regulation is poorly understood; this also applies to all other eukaryotes. Here we report the detailed characterization of the eight S. cerevisiae enzymes and show that they carry a total of 75 phosphorylation sites, 92 acetylation sites, and two ubiquitination sites. All enzymes are subject to phosphorylation, although demethylases Jhd1p and Jhd2p contained one and five sites respectively, whereas other enzymes carried 14 to 36 sites. Phosphorylation was absent or underrepresented on catalytic and other domains but strongly enriched for regions of disorder on methyltransferases, suggesting a role in the modulation of protein-protein interactions. Through mutagenesis studies, we show that phosphosites within the acidic and disordered N-terminus of Set2p affect H3K36 methylation levels in vivo, illustrating the functional importance of such sites. While most kinases upstream of the yeast histone methylation enzymes remain unknown, we model the possible connections between the cellular signaling network and the histone-based gene regulatory system and propose an integrated regulatory structure. Our results provide a foundation for future, detailed exploration of the role of specific kinases and phosphosites in the regulation of histone methylation.


Asunto(s)
Histona Metiltransferasas/metabolismo , Histonas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Metilación , Fosforilación , Procesamiento Proteico-Postraduccional
4.
Am Heart J ; 245: 10-18, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34861237

RESUMEN

BACKGROUND: Elevated Fibroblast Growth Factor-23 (FGF23) levels have been associated with greater left ventricular mass (LVM) and heart failure. Whether higher FGF23 is associated with higher LVH prevalence and longitudinal changes in LVM and myocardial strain in middle-aged adults without cardiovascular disease (CVD) or chronic kidney disease (CKD) is unknown. METHODS: We studied 3,113 adults without CVD at baseline participating in the Year 25 (2010-2011) follow-up exam of the Coronary Artery Risk Development in Young Adults (CARDIA) study. We studied the association of Year 25 c-terminal FGF23 concentrations with indexed LVM (LVMI=LVM/height2.7), LVH and myocardial strain as assessed by speckle tracking strain echocardiography. Among the 2,758 (88.6%) participants who returned for the Year 30 examination, we also investigated the association of Year 25 FGF23 with 5 Year change in LVMI, strain parameters and incident LVH. RESULTS: The mean age was 50.0 (±3.6) years, 56.8% were female, 45.7% were Black and 6.4% had CKD. There was 6.0% LVH prevalence at Year 25. Mean 5 Year change in LVMI was 5.3 (±7.7) grams/meter. In multivariable models, FGF23 in the highest quartile was associated with greater odds of LVH at Year 25 compared to lower quartiles. [Odds Ratio 95% CI: 1.81 (1.28, 2.58)] with similar findings after exclusion of participants with CKD. There was no interaction between FGF23 and race (P = .18) or sex (P = .80). There was no association between FGF23 and global longitudinal strain. There was no association between FGF23 and 5 Year change in LVMI. There was no association between higher FGF23 and 5 year incident LVH. CONCLUSIONS: In a middle-aged adult population without known CVD or CKD, higher FGF23 was associated with greater odds of LVH, but not with greater increases in LVM over time. Further study is needed to elucidate whether FGF23 is a risk marker for underlying LVH or a mechanism for increased LVM over time in younger and middle-aged adult populations without CKD.


Asunto(s)
Vasos Coronarios , Factor-23 de Crecimiento de Fibroblastos/análisis , Femenino , Factores de Crecimiento de Fibroblastos , Humanos , Hipertrofia Ventricular Izquierda , Masculino , Persona de Mediana Edad , Factores de Riesgo
5.
J Behav Med ; 45(2): 172-185, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34671896

RESUMEN

Psychosocial factors are associated with the achievement of optimal cardiovascular disease risk factor (CVDRF) levels. To date, little research has examined multiple psychosocial factors simultaneously to identify distinguishing psychosocial profiles among individuals with CVDRF. Further, it is unknown whether profiles are associated with achievement of CVDRF levels longitudinally. Therefore, we characterized psychosocial profiles of individuals with CVDRF and assessed whether they are associated with achievement of optimal CVDRF levels over 15 years. We included 1148 CARDIA participants with prevalent hypertension, hypercholesterolemia and/or diabetes mellitus in 2000-2001. Eleven psychosocial variables reflecting psychological health, personality traits, and social factors were included. Optimal levels were deemed achieved if: Hemoglobin A1c (HbA1c) < 7.0%, low-density lipoprotein (LDL) cholesterol < 100 mg/dl, and systolic blood pressure (SBP) < 140 mm Hg. Latent profile analysis revealed three psychosocial profile groups "Healthy", "Distressed and Disadvantaged" and "Discriminated Against". There were no significant differences in achievement of CVDRF levels of the 3 targets combined across profiles. Participants in the "Distressed and Disadvantaged" profile were less likely to meet optimal HbA1c levels compared to individuals in the "Healthy" profile after demographic adjustment. Associations were attenuated after full covariate adjustment. Distinct psychosocial profiles exist among individuals with CVDRF, representing meaningful differences. Implications for CVDRF management are discussed.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedades Cardiovasculares/psicología , Vasos Coronarios , Hemoglobina Glucada , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Factores de Riesgo , Adulto Joven
6.
Trends Genet ; 30(10): 430-8, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25172021

RESUMEN

Alternative splicing affects approximately 95% of eukaryotic genes, greatly expanding the coding capacity of complex genomes. Although our understanding of alternative splicing has increased rapidly, current knowledge of splicing regulation has largely been derived from studies of highly expressed mRNAs. Telomerase is a key example of a protein that is alternatively spliced, but it is expressed at very low levels and although it is known that misregulation of telomerase splicing is a hallmark of nearly all cancers, the details of this process are unclear. Here we review work showing that hTERT expression is in part regulated by atypical alternative splicing, perhaps due to its exceptionally low expression level. We propose that these differential regulatory mechanisms may be widely applicable to other genes and may provide new opportunities for the development of cancer therapeutics.


Asunto(s)
Empalme Alternativo , Regulación de la Expresión Génica , Telomerasa/genética , Animales , Moléculas de Adhesión Celular/genética , Proteínas de Drosophila/genética , Humanos , Terapia Molecular Dirigida , Neoplasias/genética , Neoplasias/terapia
7.
J Diabetes Complications ; 38(5): 108725, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38520820

RESUMEN

AIM: To assess the association of adipose-to-lean ratio (ALR) with incident type 2 diabetes mellitus (T2DM), hypertension, and dyslipidemia in middle adulthood. METHOD: Black and White Coronary Artery Risk Development in Young Adults participants without T2DM, hypertension, or dyslipidemia in 2005-06 (baseline) were included. Baseline adipose and lean mass were assessed via dual-energy X-ray absorptiometry. ALR was calculated as adipose divided by lean mass and then standardized within sex strata. Single time-point incident morbidity was assessed every five years from baseline through 2016. Cox proportional hazards regression was used to estimate hazard ratios (HR) for morbidity over 10 years per 1-SD increment in ALR adjusted for cardiovascular risk factors. RESULT: The cumulative incidence of T2DM was 7.9 % (129 events/N = 1643; 16,301 person-years), 26.7 % (485 events/N = 1819; 17,895 person-years) for hypertension, and 49.1 % (435 events/N = 855, 8089 person-years) for dyslipidemia. In the adjusted models, ALR was positively associated with a risk of T2DM (HR [95 % CI]; 1.69 [1.31, 2.19]) and hypertension (1.23 [1.08, 1.40]). There was no significant interaction between ALR and sex for any morbidity. CONCLUSION: ALR in middle adulthood is associated with incident T2DM and hypertension. The extent to which localized body composition measures might inform morbidity risk merits further investigation.


Asunto(s)
Diabetes Mellitus Tipo 2 , Dislipidemias , Hipertensión , Humanos , Masculino , Femenino , Adulto , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Incidencia , Estudios Longitudinales , Hipertensión/epidemiología , Hipertensión/complicaciones , Adulto Joven , Dislipidemias/epidemiología , Dislipidemias/complicaciones , Adiposidad/fisiología , Adolescente , Persona de Mediana Edad , Composición Corporal , Tejido Adiposo , Enfermedades Cardiovasculares/epidemiología , Estados Unidos/epidemiología , Factores de Riesgo Cardiometabólico , Absorciometría de Fotón
8.
Am J Prev Med ; 67(1): 24-31, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38143043

RESUMEN

INTRODUCTION: Higher levels of perceived stress are associated with adverse cardiovascular health. It is plausible that these associations are attenuated among individuals with positive psychological factors such as social support and health-enhancing behaviors. Therefore, this study examined longitudinal associations of chronic stress with cardiovascular disease (CVD) events, and whether social support and physical activity (PA) modify these associations. METHODS: Data from 3,401 adults (mean age 40.2 years; 46.7% Black; 56.2% women) from the Coronary Artery Risk Development in Young Adults (CARDIA) study, with no prior CVD event in 2000-2001 were analyzed. Chronic stress lasting ≥6 months across 5 life domains (work, financial, relationships, health of self, and health of close other) was self-reported. Adjudicated CVD events (fatal/or nonfatal CVD event) were ascertained yearly through 2020. PA and social support were self-reported via questionnaires. Statistical analyses were conducted in 2023 using multivariable stepwise Accelerated Failure Time analysis to assess associations between key study variables. RESULTS: The mean chronic stress score was 1.30±1.33 stressors and, by 2020, 220 participants had experienced a CVD event. Chronic stress was associated with lowered survival (time ratio: 0.92; 95% CI: 0.854-0.989), when adjusted for sociodemographic and lifestyle variables but no longer significant when adjusting for clinical factors. Neither PA nor social support were significant modifiers (all ps>0.05). CONCLUSIONS: Chronic stress was associated with the risk of having a CVD event among middle-aged adults, due at least in part to clinical mediators. Studies should continue exploring positive psychosocial and behavioral factors that may modify this association.


Asunto(s)
Enfermedades Cardiovasculares , Ejercicio Físico , Apoyo Social , Estrés Psicológico , Humanos , Femenino , Masculino , Estrés Psicológico/epidemiología , Adulto , Enfermedades Cardiovasculares/epidemiología , Estudios Longitudinales , Persona de Mediana Edad , Autoinforme , Factores de Riesgo , Enfermedad Crónica/epidemiología , Encuestas y Cuestionarios , Adulto Joven
9.
Nat Commun ; 15(1): 1880, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38424098

RESUMEN

Drugs that target pre-mRNA splicing hold great therapeutic potential, but the quantitative understanding of how these drugs work is limited. Here we introduce mechanistically interpretable quantitative models for the sequence-specific and concentration-dependent behavior of splice-modifying drugs. Using massively parallel splicing assays, RNA-seq experiments, and precision dose-response curves, we obtain quantitative models for two small-molecule drugs, risdiplam and branaplam, developed for treating spinal muscular atrophy. The results quantitatively characterize the specificities of risdiplam and branaplam for 5' splice site sequences, suggest that branaplam recognizes 5' splice sites via two distinct interaction modes, and contradict the prevailing two-site hypothesis for risdiplam activity at SMN2 exon 7. The results also show that anomalous single-drug cooperativity, as well as multi-drug synergy, are widespread among small-molecule drugs and antisense-oligonucleotide drugs that promote exon inclusion. Our quantitative models thus clarify the mechanisms of existing treatments and provide a basis for the rational development of new therapies.


Asunto(s)
Atrofia Muscular Espinal , Pirimidinas , Empalme del ARN , Humanos , Empalme del ARN/genética , Compuestos Azo , Oligonucleótidos/genética , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/uso terapéutico , Sitios de Empalme de ARN , Atrofia Muscular Espinal/tratamiento farmacológico , Atrofia Muscular Espinal/genética
10.
JCI Insight ; 9(8)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38451719

RESUMEN

Mesenchymal stem cells (MSCs), suffering from diverse gene hits, undergo malignant transformation and aberrant osteochondral differentiation. Src homology region 2-containing protein tyrosine phosphatase 2 (SHP2), a nonreceptor protein tyrosine phosphatase, regulates multicellular differentiation, proliferation, and transformation. However, the role of SHP2 in MSC fate determination remains unclear. Here, we showed that MSCs bearing the activating SHP2E76K mutation underwent malignant transformation into sarcoma stem-like cells. We revealed that the SHP2E76K mutation in mouse MSCs led to hyperactive mitochondrial metabolism by activating mitochondrial complexes I and III. Inhibition of complexes I and III prevented hyperactive mitochondrial metabolism and malignant transformation of SHP2E76K MSCs. Mechanistically, we verified that SHP2 underwent liquid-liquid phase separation (LLPS) in SHP2E76K MSCs. SHP2 LLPS led to its dissociation from complexes I and III, causing their hyperactivation. Blockade of SHP2 LLPS by LLPS-defective mutations or allosteric inhibitors suppressed complex I and III hyperactivation as well as malignant transformation of SHP2E76K MSCs. These findings reveal that complex I and III hyperactivation driven by SHP2 LLPS promotes malignant transformation of SHP2E76K MSCs and suggest that inhibition of SHP2 LLPS could be a potential therapeutic target for the treatment of activated SHP2-associated cancers.


Asunto(s)
Transformación Celular Neoplásica , Células Madre Mesenquimatosas , Mitocondrias , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Células Madre Mesenquimatosas/metabolismo , Animales , Ratones , Mitocondrias/metabolismo , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Humanos , Mutación , Diferenciación Celular , Separación de Fases
11.
Ocul Immunol Inflamm ; 31(7): 1490-1496, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35914307

RESUMEN

PURPOSE: To describe the two-year outcome of trabeculectomy in cytomegalovirus(CMV) anterior uveitis(AU). METHODS: Records of 29 eyes of 29 consecutive CMV AU patients undergoing MMC-augmented trabeculectomy for uncontrolled IOP despite maximal tolerated topical medications were retrospectively reviewed. Treatment success was defined as IOP≤21 mmHg with same or reduced number of IOP-lowering medications compared to baseline, without systemic acetazolamide or further interventions for uncontrolled IOP. RESULTS: Treatment success was 79.3% (23/29) at 24 months. Both median IOP and number of IOP-lowering medications dropped significantly from baseline (p < .01 and p < .001, all time-points, Wilcoxon sign-rank test, respectively), with 63.2% and 19.0% reduction in AU relapse/year and steroid use(p = .001 and 0.03, respectively), without sight-threatening sequelae. At 24 months, AU frequency was not significantly different between successful cases with and without ≥12-month use of topical ganciclovir (p = .51, Mann-Whitney U test). CONCLUSION: MMC-augmented trabeculectomy was efficacious for IOP control in nearly 80% of CMV AU cases over two years.


Asunto(s)
Infecciones por Citomegalovirus , Glaucoma , Trabeculectomía , Uveítis Anterior , Humanos , Presión Intraocular , Glaucoma/cirugía , Citomegalovirus , Estudios Retrospectivos , Mitomicina/uso terapéutico , Uveítis Anterior/tratamiento farmacológico , Resultado del Tratamiento , Infecciones por Citomegalovirus/tratamiento farmacológico
12.
Children (Basel) ; 10(2)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36832310

RESUMEN

Pediatric glaucoma (PG) covers a rare and heterogeneous group of diseases with variable causes and presentations. Delayed diagnosis of PG could lead to blindness, bringing emotional and psychological burdens to patients' caregivers. Recent genetic studies identified novel causative genes, which may provide new insight into the etiology of PG. More effective screening strategies could be beneficial for timely diagnosis and treatment. New findings on clinical characteristics and the latest examination instruments have provided additional evidence for diagnosing PG. In addition to IOP-lowering therapy, managing concomitant amblyopia and other associated ocular pathologies is essential to achieve a better visual outcome. Surgical treatment is usually required although medication is often used before surgery. These include angle surgeries, filtering surgeries, minimally invasive glaucoma surgeries, cyclophotocoagulation, and deep sclerectomy. Several advanced surgical therapies have been developed to increase success rates and decrease postoperative complications. Here, we review the classification and diagnosis, etiology, screening, clinical characteristics, examinations, and management of PG.

13.
J AAPOS ; 27(2): 93.e1-93.e4, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36801243

RESUMEN

PURPOSE: To report clinical outcomes and risk factors for glaucoma in children and adolescents referred for increased cup:disk ratios (CDRs) to a tertiary referral center. METHODS: This retrospective, single-center study examined all pediatric patients evaluated for increased CDR at Wills Eye Hospital. Patients who had previous known ocular disease were excluded. Demographic data, including sex, age, and race/ethnicity were recorded, as were baseline and follow-up ophthalmic examination findings, including intraocular pressure (IOP), CDR, diurnal curve, gonioscopy findings, and refractive error. Risks of glaucoma diagnosis based on these data were analyzed. RESULTS: A total of 167 patients were included, of whom 6 were found to have glaucoma. Despite more than 2 years' follow-up on 61 patients, all glaucoma patients were identified within the first 3 months of evaluation. Baseline IOP was statistically significantly higher in glaucomatous patients than nonglaucomatous patients (28 ± 7 vs 15 ± 4, resp. [P = 0.0002]), as was maximum IOP on diurnal curve (24 ± 3 vs 17 ± 3 [P = 0.0005]). CONCLUSIONS: In our study cohort, diagnosis of glaucoma was apparent in the first year of evaluation. Baseline IOP and maximal IOP on diurnal curve were found to be statistically significantly associated with glaucoma diagnosis in pediatric patients referred for increased CDR.


Asunto(s)
Glaucoma de Ángulo Abierto , Glaucoma , Humanos , Adolescente , Niño , Estudios Retrospectivos , Centros de Atención Terciaria , Glaucoma/diagnóstico , Presión Intraocular
14.
Am J Ophthalmol ; 247: 111-120, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36220350

RESUMEN

PURPOSE: To determine the relationship between baseline retinal-vessel calibers computed by a deep-learning system and the risk of normal tension glaucoma (NTG) progression. DESIGN: Prospective cohort study. METHODS: Three hundred and ninety eyes from 197 patients with NTG were followed up for at least 24 months. Retinal-vessel calibers (central retinal arteriolar equivalent [CRAE] and central retinal venular equivalent [CRVE]) were computed from fundus photographs at baseline using a previously validated deep-learning system. Retinal nerve fiber layer (RNFL) thickness and visual field (VF) were evaluated semiannually. The Cox proportional-hazards model was used to evaluate the relationship of baseline retinal-vessel calibers to the risk of glaucoma progression. RESULTS: Over a mean follow-up period of 34.36 ± 5.88 months, 69 NTG eyes (17.69%) developed progressive RNFL thinning and 22 eyes (5.64%) developed VF deterioration. In the multivariable Cox regression analysis adjusting for age, gender, intraocular pressure, mean ocular perfusion pressure, systolic blood pressure, axial length, standard automated perimetry mean deviation, and RNFL thickness, narrower baseline CRAE (hazard ratio per SD decrease [95% confidence interval], 1.36 [1.01-1.82]) and CRVE (1.35 [1.01-1.80]) were associated with progressive RNFL thinning and narrower baseline CRAE (1.98 [1.17-3.35]) was associated with VF deterioration. CONCLUSION: In this study, each SD decrease in the baseline CRAE or CRVE was associated with a more than 30% increase in the risk of progressive RNFL thinning and a more than 90% increase in the risk of VF deterioration during the follow-up period. Baseline attenuation of retinal vasculature in NTG eyes was associated with subsequent glaucoma progression. High-throughput deep-learning-based retinal vasculature analysis demonstrated its clinical utility for NTG risk assessment.


Asunto(s)
Glaucoma de Ángulo Abierto , Glaucoma , Glaucoma de Baja Tensión , Degeneración Retiniana , Humanos , Estudios Prospectivos , Células Ganglionares de la Retina , Tomografía de Coherencia Óptica , Vasos Retinianos , Glaucoma/complicaciones , Presión Intraocular , Degeneración Retiniana/complicaciones
15.
Obesity (Silver Spring) ; 31(5): 1402-1414, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37041722

RESUMEN

OBJECTIVE: The aim of this study was to quantify the contributions of socioeconomic, psychosocial, behavioral, reproductive, and neighborhood exposures in young adulthood to Black-White differences in incident obesity. METHODS: In the Coronary Artery Risk Development in Young Adults (CARDIA) study, 4488 Black or White adults aged 18 to 30 years without obesity at baseline (1985-1986) were followed over 30 years. Sex-specific Cox proportional hazard models were used to estimate Black-White differences in incident obesity. Models were adjusted for baseline and time-updated indicators. RESULTS: During follow-up, 1777 participants developed obesity. Black women were 1.87 (95% CI: 1.63-2.13) times more likely and Black men were 1.53 (95% CI: 1.32-1.77) times more likely to develop obesity than their White counterparts after adjusting for age, field center, and baseline BMI. Baseline exposures explained 43% of this difference in women and 52% in men. Time-updated exposures explained more of the racial difference in women but less for men, compared with baseline exposures. CONCLUSIONS: Adjusting for these exposures accounted for a substantial but incomplete proportion of racial disparities in incident obesity. Remaining differences may be explained by incomplete capture of the most salient aspects of these exposures or potential variation in the impact of these exposures on obesity by race.


Asunto(s)
Negro o Afroamericano , Disparidades en el Estado de Salud , Obesidad , Población Blanca , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Obesidad/epidemiología , Factores de Riesgo , Adolescente
16.
BMJ Open ; 13(11): e073734, 2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37918924

RESUMEN

INTRODUCTION: Cognitive dysfunction, a leading cause of mortality and morbidity in the USA and globally, has been shown to disproportionately affect the socioeconomically disadvantaged and those who identify as black or Hispanic/Latinx. Poor sleep is strongly associated with the development of vascular and metabolic diseases, which correlate with cognitive dysfunction. Therefore, sleep may contribute to observed disparities in cognitive disorders. The Epidemiologic Study of Disparities in Sleep and Cognition in Older Adults (DISCO) is a longitudinal, observational cohort study that focuses on gathering data to better understand racial/ethnic sleep disparities and illuminate the relationship among sleep, race and ethnicity and changes in cognitive function. This investigation may help inform targeted interventions to minimise disparities in cognitive health among ageing adults. METHODS AND ANALYSIS: The DISCO study will examine up to 495 individuals aged 55 and older at two time points over 24 months. An equal number of black, white and Hispanic/Latinx individuals will be recruited using methods aimed for adults traditionally under-represented in research. Study procedures at each time point will include cognitive tests, gait speed measurement, wrist actigraphy, a type 2 home polysomnography and a clinical examination. Participants will also complete self-identified assessments and questionnaires on cognitive ability, sleep, medication use, quality of life, sociodemographic characteristics, diet, substance use, and psychological and social health. ETHICS AND DISSEMINATION: This study was approved by the Northwestern University Feinberg School of Medicine Institutional Review Board. Deidentified datasets will be shared via the BioLINCC repository following the completion of the project. Biospecimen samples from the study that are not being analysed can be made available to qualified investigators on review and approval by study investigators. Requests that do not lead to participant burden or that conflict with the primary aims of the study will be reviewed by the study investigators.


Asunto(s)
Disfunción Cognitiva , Calidad de Vida , Humanos , Anciano , Autoinforme , Sueño , Cognición , Disfunción Cognitiva/psicología , Estudios Observacionales como Asunto
17.
Br J Ophthalmol ; 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37857452

RESUMEN

BACKGROUND: Deep learning (DL) is promising to detect glaucoma. However, patients' privacy and data security are major concerns when pooling all data for model development. We developed a privacy-preserving DL model using the federated learning (FL) paradigm to detect glaucoma from optical coherence tomography (OCT) images. METHODS: This is a multicentre study. The FL paradigm consisted of a 'central server' and seven eye centres in Hong Kong, the USA and Singapore. Each centre first trained a model locally with its own OCT optic disc volumetric dataset and then uploaded its model parameters to the central server. The central server used FedProx algorithm to aggregate all centres' model parameters. Subsequently, the aggregated parameters are redistributed to each centre for its local model optimisation. We experimented with three three-dimensional (3D) networks to evaluate the stabilities of the FL paradigm. Lastly, we tested the FL model on two prospectively collected unseen datasets. RESULTS: We used 9326 volumetric OCT scans from 2785 subjects. The FL model performed consistently well with different networks in 7 centres (accuracies 78.3%-98.5%, 75.9%-97.0%, and 78.3%-97.5%, respectively) and stably in the 2 unseen datasets (accuracies 84.8%-87.7%, 81.3%-84.8%, and 86.0%-87.8%, respectively). The FL model achieved non-inferior performance in classifying glaucoma compared with the traditional model and significantly outperformed the individual models. CONCLUSION: The 3D FL model could leverage all the datasets and achieve generalisable performance, without data exchange across centres. This study demonstrated an OCT-based FL paradigm for glaucoma identification with ensured patient privacy and data security, charting another course toward the real-world transition of artificial intelligence in ophthalmology.

18.
Phlebology ; 38(4): 205-258, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36916540

RESUMEN

BACKGROUND: Sclerotherapy is a non-invasive procedure commonly used to treat superficial venous disease, vascular malformations and other ectatic vascular lesions. While extremely rare, sclerotherapy may be complicated by serious adverse events. OBJECTIVES: To categorise contraindications to sclerotherapy based on the available scientific evidence. METHODS: An international, multi-disciplinary panel of phlebologists reviewed the available scientific evidence and developed consensus where evidence was lacking or limited. RESULTS: Absolute Contraindications to sclerotherapy where the risk of harm would outweigh any benefits include known hypersensitivity to sclerosing agents; acute venous thromboembolism (VTE); severe neurological or cardiac adverse events complicating a previous sclerotherapy treatment; severe acute systemic illness or infection; and critical limb ischaemia. Relative Contraindications to sclerotherapy where the potential benefits of the proposed treatment would outweigh the risk of harm or the risks may be mitigated by other measures include pregnancy, postpartum and breastfeeding; hypercoagulable states with risk of VTE; risk of neurological adverse events; risk of cardiac adverse events and poorly controlled chronic systemic illness. Conditions and circumstances where Warnings and Precautions should be considered before proceeding with sclerotherapy include risk of cutaneous necrosis or cosmetic complications such as pigmentation and telangiectatic matting; intake of medications such as the oral contraceptive and other exogenous oestrogens, disulfiram and minocycline; and psychosocial factors and psychiatric comorbidities that may increase the risk of adverse events or compromise optimal treatment outcomes. CONCLUSIONS: Sclerotherapy can achieve safe clinical outcomes provided that (1) patient-related risk factors and in particular all material risks are (1a) adequately identified and the risk benefit ratio is clearly and openly discussed with treatment candidates within a reasonable timeframe prior to the actual procedure; (1b) when an individual is not a suitable candidate for the proposed intervention, conservative treatment options including the option of 'no intervention as a treatment option' are discussed; (1c) complex cases are referred for treatment in controlled and standardised settings and by practitioners with more expertise in the field; (1d) only suitable individuals with no absolute contraindications or those with relative contraindications where the benefits outweigh the risks are offered intervention; (1e) if proceeding with intervention, appropriate prophylactic measures and other risk-mitigating strategies are adopted and appropriate follow-up is organised; and (2) procedure-related risk factors are minimised by ensuring the treating physicians (2a) have adequate training in general phlebology with additional training in duplex ultrasound, procedural phlebology and in particular sclerotherapy; (2b) maintain their knowledge and competency over time and (2c) review and optimise their treatment strategies and techniques on a regular basis to keep up with the ongoing progress in medical technology and contemporary scientific evidence.


Asunto(s)
Escleroterapia , Tromboembolia Venosa , Embarazo , Femenino , Humanos , Escleroterapia/efectos adversos , Consenso , Tromboembolia Venosa/etiología , Contraindicaciones , Extremidad Inferior
19.
Front Immunol ; 13: 868813, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35514975

RESUMEN

Breast cancer development and progression rely not only on the proliferation of neoplastic cells but also on the significant heterogeneity in the surrounding tumor microenvironment. Its unique microenvironment, including tumor-infiltrating lymphocytes, complex myeloid cells, lipid-associated macrophages, cancer-associated fibroblasts (CAFs), and other molecules that promote the growth and migration of tumor cells, has been shown to play a crucial role in the occurrence, growth, and metastasis of breast cancer. However, a detailed understanding of the complex microenvironment in breast cancer remains largely unknown. The unique pattern of breast cancer microenvironment cells has been poorly studied, and neither has the supportive role of these cells in pathogenesis been assessed. Single-cell multiomics biotechnology, especially single-cell RNA sequencing (scRNA-seq) reveals single-cell expression levels at much higher resolution, finely dissecting the molecular characteristics of tumor microenvironment. Here, we review the recent literature on breast cancer microenvironment, focusing on scRNA-seq studies and analyzing heterogeneity and spatial location of different cells, including T and B cells, macrophages/monocytes, neutrophils, and stromal cells. This review aims to provide a more comprehensive perception of breast cancer microenvironment and annotation for their clinical classification, diagnosis, and treatment. Furthermore, we discuss the impact of novel single-cell omics technologies, such as abundant omics exploration strategies, multiomics conjoint analysis mode, and deep learning network architecture, on the future research of breast cancer immune microenvironment.


Asunto(s)
Neoplasias de la Mama , Fibroblastos Asociados al Cáncer , Neoplasias de la Mama/patología , Fibroblastos Asociados al Cáncer/metabolismo , Femenino , Humanos , Linfocitos Infiltrantes de Tumor , Análisis de la Célula Individual , Microambiente Tumoral
20.
Front Cell Dev Biol ; 10: 857045, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35756991

RESUMEN

Bone marrow microenvironment (BMM) has been proven to have benefits for both normal hematopoietic stem cell niche and pathological leukemic stem cell niche. In fact, the pathological leukemia microenvironment reprograms bone marrow niche cells, especially mesenchymal stem cells for leukemia progression, chemoresistance and relapse. The growth and differentiation of MSCs are modulated by leukemia stem cells. Moreover, chromatin abnormality of mesenchymal stem cells is sufficient for leukemia initiation. Here, we summarize the detailed relationship between MSC and leukemia. MSCs can actively and passively regulate the progression of myelogenous leukemia through cell-to-cell contact, cytokine-receptor interaction, and exosome communication. These behaviors benefit LSCs proliferation and survival and inhibit physiological hematopoiesis. Finally, we describe the recent advances in therapy targeting MSC hoping to provide new perspectives and therapeutic strategies for leukemia.

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