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INTRODUCTION: Aim is to evaluate geographical and demographic factors influencing management of bile duct injuries occurring during cholecystectomy in a tertiary hepato-pancreato-biliary center in Southeast US. METHODS: All referrals for biliary injuries during cholecystectomy, between Jan 2017 and December 2020 were included. RESULTS: 19 patients were identified with a median age of 59 (47-65), average BMI of 30.3 (18-49), and the prevalence of diabetes mellitus, hypertension and cardiovascular disease of 11%, 47% and 16%, respectively. The average transfer distance was 76 miles (8-102) and median transfer time was 3 days (1-12). 16 (84%) had Strasberg E injury, with 4 (21%) having a concomitant vascular injury (3 - right hepatic artery, 1 - right portal vein). Two (10.5%) were managed non-operatively, immediate surgical repair was performed in 2 (10.5%) and 15 (78.9%) patients underwent a delayed repair with a median of 87 days (69-118) from injury to repair. Median operative time was 5 hours (4-7), blood loss was 150 mL (100-200) and hospital stay was 8 days (6-12). DISCUSSION: Factors including distance between hospitals, delays in patient transfer due to bed availability and transportation, play a role in the decision-making towards delayed repair. The delayed repair has the benefit of medical optimization of our high-risk patients' population.
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Colecistectomía Laparoscópica , Humanos , Colecistectomía Laparoscópica/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento , Conductos Biliares/cirugía , Conductos Biliares/lesiones , Derivación y ConsultaRESUMEN
OBJECTIVE: To explore longitudinal changes in brain volumetric measures and retinal layer thicknesses following acute optic neuritis (AON) in people with multiple sclerosis (PwMS), to investigate the process of trans-synaptic degeneration, and determine its clinical relevance. METHODS: PwMS were recruited within 40 days of AON onset (n = 49), and underwent baseline retinal optical coherence tomography and brain magnetic resonance imaging followed by longitudinal tracking for up to 5 years. A comparator cohort of PwMS without a recent episode of AON were similarly tracked (n = 73). Mixed-effects linear regression models were used. RESULTS: Accelerated atrophy of the occipital gray matter (GM), calcarine GM, and thalamus was seen in the AON cohort, as compared with the non-AON cohort (-0.76% vs -0.22% per year [p = 0.01] for occipital GM, -1.83% vs -0.32% per year [p = 0.008] for calcarine GM, -1.17% vs -0.67% per year [p = 0.02] for thalamus), whereas rates of whole-brain, cortical GM, non-occipital cortical GM atrophy, and T2 lesion accumulation did not differ significantly between the cohorts. In the AON cohort, greater AON-induced reduction in ganglion cell+inner plexiform layer thickness over the first year was associated with faster rates of whole-brain (r = 0.32, p = 0.04), white matter (r = 0.32, p = 0.04), and thalamic (r = 0.36, p = 0.02) atrophy over the study period. Significant relationships were identified between faster atrophy of the subcortical GM and thalamus, with worse visual function outcomes after AON. INTERPRETATION: These results provide in-vivo evidence for anterograde trans-synaptic degeneration following AON in PwMS, and suggest that trans-synaptic degeneration may be related to clinically-relevant visual outcomes. ANN NEUROL 2023;93:76-87.
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Esclerosis Múltiple , Neuritis Óptica , Humanos , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Degeneración Retrógrada/patología , Neuritis Óptica/diagnóstico por imagen , Neuritis Óptica/etiología , Retina/diagnóstico por imagen , Retina/patología , Imagen por Resonancia Magnética , Tomografía de Coherencia Óptica , Atrofia/patologíaRESUMEN
BACKGROUND: Fatigue after thyroidectomy is common, but there is a paucity of data regarding its prevalence and duration. We hypothesized that total thyroidectomy (TT) patients would have more long-term fatigue than thyroid lobectomy (TL) patients. METHODS: Statewide survey of thyroidectomy patients (2004-2017) was carried out. RESULTS: 281 patients completed the survey. 216 respondents (77%) had TT and 65 (23%) had TL. Within one year of surgery, 172 (61%) respondents recalled being troubled by new fatigue all, most, or some of the time. Total thyroidectomy patients were more likely to report new fatigue (69% vs. 44%, aOR 2.72, 95% CI 1.44 to 5.18). Of patients (n = 172) reporting new fatigue, 67 (39%) reported at least moderate improvement. Nineteen (28%) saw improvement within 1 year, 35 (52%) saw improvement in 1-2 years, and 11 (16%) saw improvement after 2 years. CONCLUSION: Long-term fatigue after TT can be debilitating, long-lasting, and less prevalent after TL.
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Síndrome de Fatiga Crónica/epidemiología , Complicaciones Posoperatorias/epidemiología , Tiroidectomía/efectos adversos , Intervalos de Confianza , Estudios Transversales , Femenino , Encuestas Epidemiológicas/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Evaluación de Resultado en la Atención de Salud , Investigación Cualitativa , Tiroidectomía/métodosRESUMEN
BACKGROUND: Surgical axillary staging demonstrating positive nodal disease before neoadjuvant chemotherapy (NAC) necessitates axillary lymph node dissection (ALND) post-NAC. Despite evidence supporting post-NAC surgical staging, we hypothesized that there is persistent use of pre-NAC staging and that it is associated with aggressive clinicopathologic features and a higher rate of subsequent ALND. PATIENTS AND METHODS: Stage I-III breast cancer patients who underwent lymph node staging surgery and received NAC between 2013 and 2017 in the National Cancer Database were included. Sequence of staging surgery and chemotherapy administration was determined. Multivariable regression was used to assess characteristics associated with pre-NAC staging. Rate of ALND was compared between those who had pre- and post-NAC surgical axillary staging. RESULTS: In total, 120,538 met inclusion; 68% received NAC first and 32% had pre-NAC staging. Pre-NAC staging surgery was associated with younger age (age < 30 versus 40-49 years, HR 1.1) and decreased with older age (ages 70-79/80+ versus 40-49 years, HR 0.86 and 0.73). Advancing clinical T stage, lobular subtype, higher grade, and HR+/HER2- subtype were also associated with pre-NAC surgical staging. Women who underwent pre-NAC surgical staging were more likely to undergo ALND. CONCLUSIONS: Over 30% of women underwent surgical axillary staging prior to NAC, resulting in higher rates of ALND in this cohort. While certain features suggestive of aggressive behavior (grade and T stage) were associated with pre-NAC surgical axillary staging, women with more aggressive tumor subtypes (triple negative/HER2+) were less likely to undergo pre-NAC surgical axillary staging. Pre-NAC surgical axillary staging should be performed only in rare circumstances to avoid unnecessary ALND.
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Neoplasias de la Mama , Terapia Neoadyuvante , Adulto , Anciano , Axila/patología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Femenino , Humanos , Escisión del Ganglio Linfático , Persona de Mediana Edad , Estadificación de Neoplasias , Biopsia del Ganglio Linfático CentinelaRESUMEN
Chronic disability in multiple sclerosis is linked to neuroaxonal degeneration. 4-aminopyridine (4-AP) is used and licensed as a symptomatic treatment to ameliorate ambulatory disability in multiple sclerosis. The presumed mode of action is via blockade of axonal voltage gated potassium channels, thereby enhancing conduction in demyelinated axons. In this study, we provide evidence that in addition to those symptomatic effects, 4-AP can prevent neuroaxonal loss in the CNS. Using in vivo optical coherence tomography imaging, visual function testing and histologic assessment, we observed a reduction in retinal neurodegeneration with 4-AP in models of experimental optic neuritis and optic nerve crush. These effects were not related to an anti-inflammatory mode of action or a direct impact on retinal ganglion cells. Rather, histology and in vitro experiments indicated 4-AP stabilization of myelin and oligodendrocyte precursor cells associated with increased nuclear translocation of the nuclear factor of activated T cells. In experimental optic neuritis, 4-AP potentiated the effects of immunomodulatory treatment with fingolimod. As extended release 4-AP is already licensed for symptomatic multiple sclerosis treatment, we performed a retrospective, multicentre optical coherence tomography study to longitudinally compare retinal neurodegeneration between 52 patients on continuous 4-AP therapy and 51 matched controls. In line with the experimental data, during concurrent 4-AP therapy, degeneration of the macular retinal nerve fibre layer was reduced over 2 years. These results indicate disease-modifying effects of 4-AP beyond symptomatic therapy and provide support for the design of a prospective clinical study using visual function and retinal structure as outcome parameters.
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4-Aminopiridina/farmacología , Esclerosis Múltiple/patología , Fármacos Neuroprotectores/farmacología , Neuritis Óptica/patología , Degeneración Retiniana/patología , Adulto , Anciano , Animales , Encefalomielitis Autoinmune Experimental/patología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Células-Madre Neurales/efectos de los fármacos , Bloqueadores de los Canales de Potasio/farmacología , Ratas , Ratas WistarRESUMEN
OBJECTIVE: Therapeutic development in progressive multiple sclerosis (PMS) has been hampered by a lack of reliable biomarkers to monitor neurodegeneration. Optical coherence tomography (OCT)-derived retinal measures have been proposed as promising biomarkers to fulfill this role. However, it is unclear whether retinal atrophy persists in PMS, exceeds normal aging, or can be distinguished from relapsing-remitting multiple sclerosis (RRMS). METHODS: 178 RRMS, 186 PMS, and 66 control participants were followed with serial OCT for a median follow-up of 3.7 years. RESULTS: The estimated proportion of peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell + inner plexiform layer (GCIPL) thinning in multiple sclerosis (MS) attributable to normal aging increased from 42.7% and 16.7% respectively at age 25 years, to 83.7% and 81.1% at age 65 years. However, independent of age, PMS was associated with faster pRNFL (-0.34 ± 0.09%/yr, p < 0.001) and GCIPL (-0.27 ± 0.07%/yr, p < 0.001) thinning, as compared to RRMS. In both MS and controls, higher baseline age was associated with faster inner nuclear layer (INL) and outer nuclear layer (ONL) thinning. INL and ONL thinning were independently faster in PMS, as compared to controls (INL:-0.09 ± 0.04%/yr, p = 0.03; ONL:-0.12 ± 0.06%/yr, p = 0.04), and RRMS (INL:-0.10 ± 0.04%/yr, p = 0.01; ONL:-0.13 ± 0.05%/yr, p = 0.01), whereas they were similar in RRMS and controls. Unlike RRMS, disease-modifying therapies (DMTs) did not impact rates of retinal layer atrophy in PMS. INTERPRETATION: PMS is associated with faster retinal atrophy independent of age. INL and ONL measures may be novel biomarkers of neurodegeneration in PMS that appear to be unaffected by conventional DMTs. The effects of aging on rates of retinal layer atrophy should be considered in clinical trials incorporating OCT outcomes. ANN NEUROL 2020;87:885-896.
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Esclerosis Múltiple Crónica Progresiva/diagnóstico por imagen , Retina/diagnóstico por imagen , Adolescente , Adulto , Anciano , Atrofia , Biomarcadores , Diagnóstico Diferencial , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Crónica Progresiva/diagnóstico , Esclerosis Múltiple Recurrente-Remitente/diagnóstico , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Fibras Nerviosas/patología , Degeneración Retiniana/patología , Células Ganglionares de la Retina/patología , Tomografía de Coherencia Óptica , Adulto JovenRESUMEN
Objective: Optical coherence tomography (OCT)-derived measures of the retina correlate with disability and cortical gray matter atrophy in multiple sclerosis (MS); however, whether such measures predict long-term disability is unknown. We evaluated whether a single OCT and visual function assessment predict the disability status 10 years later. Methods: Between 2006 and 2008, 172 people with MS underwent Stratus time domain-OCT imaging [160 with measurement of total macular volume (TMV)] and high and low-contrast letter acuity (LCLA) testing (n = 150; 87%). All participants had Expanded Disability Status Scale (EDSS) assessments at baseline and at 10-year follow-up. We applied generalized linear regression models to assess associations between baseline TMV, peripapillary retinal nerve fiber layer (pRNFL) thickness, and LCLA with 10-year EDSS scores (linear) and with clinically significant EDSS worsening (binary), adjusting for age, sex, optic neuritis history, and baseline disability status. Results: In multivariable models, lower baseline TMV was associated with higher 10-year EDSS scores (mean increase in EDSS of 0.75 per 1 mm3 loss in TMV (mean difference = 0.75; 95% CI: 0.11-1.39; P = 0.02). In analyses using tertiles, individuals in the lowest tertile of baseline TMV had an average 0.86 higher EDSS scores at 10 years (mean difference = 0.86; 95% CI: 0.23-1.48) and had over 3.5-fold increased odds of clinically significant EDSS worsening relative to those in the highest tertile of baseline TMV (OR: 3.58; 95% CI: 1.30-9.82; P trend = 0.008). pRNFL and LCLA predicted the 10-year EDSS scores only in univariate models. Interpretation: Lower baseline TMV measured by OCT significantly predicts higher disability at 10 years, even after accounting for baseline disability status.
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Esclerosis Múltiple/fisiopatología , Neuritis Óptica/fisiopatología , Retina/fisiopatología , Células Ganglionares de la Retina/patología , Adulto , Atrofia/complicaciones , Atrofia/fisiopatología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Esclerosis Múltiple/complicaciones , Neuritis Óptica/complicaciones , Retina/patología , Tomografía de Coherencia Óptica/métodosRESUMEN
BACKGROUND: Morphologic macular abnormalities (MMAs) are frequently seen on macular optical coherence tomography (OCT) imaging in neuroimmunology practice, yet studies pragmatically assessing prevalence and risk factors of MMAs to date are limited. OBJECTIVE: To describe the characteristics of MMAs in a neuroimmunology-based academic practice. METHODS: Cross-sectional study of 1450 patients (2900 eyes) who underwent spectral-domain macular OCT between June 2010 and June 2012. The association between MMAs and demographic variables was analyzed using mixed-effects logistic regression. Odds ratios (ORs) were calculated per 5-year age increments. RESULTS: MMAs were observed in 338/2872 eyes (11.7%) of 232/1445 participants (16.1%). The most common abnormalities identified, included drusen (6.0%), epiretinal membrane (ERM; 5.5%), and microcystoid macular pathology (MMP; 1.9%). Overall, patients with MMAs were older (OR: 1.79, p = 5 × 10-5) and more likely to be males (OR: 2.45, p = 0.014). In particular, advancing age was associated with higher risk of drusen and ERM (OR: 1.80 and 4.26, p = 2 × 10-5 and 7 × 10-3, respectively). MMP prevalence declined with age (OR: 0.73, p = 0.015) and was associated with African-American ethnicity (OR: 15.0, p = 5 × 10-5). CONCLUSION: Unexpected or incidental MMAs are common in patients assessed with OCT in neuroimmunology practice, emphasizing the importance of comprehensive OCT image review for risk stratification and appropriate ophthalmology referral.
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Esclerosis Múltiple/diagnóstico por imagen , Enfermedades de la Retina/diagnóstico por imagen , Centros Médicos Académicos , Adulto , Anciano , Estudios Transversales , Membrana Epirretinal/diagnóstico por imagen , Membrana Epirretinal/epidemiología , Membrana Epirretinal/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/epidemiología , Enfermedades de la Retina/epidemiología , Tomografía de Coherencia ÓpticaRESUMEN
The data presented in this article is related to the research article entitled "Longitudinal multiple sclerosis lesion segmentation: Resource and challenge" (Carass et al., 2017) [1]. In conjunction with the 2015 International Symposium on Biomedical Imaging, we organized a longitudinal multiple sclerosis (MS) lesion segmentation challenge providing training and test data to registered participants. The training data consists of five subjects with a mean of 4.4 (±0.55) time-points, and test data of fourteen subjects with a mean of 4.4 (±0.67) time-points. All 82 data sets had the white matter lesions associated with multiple sclerosis delineated by two human expert raters. The training data including multi-modal scans and manually delineated lesion masks is available for download. In addition, the testing data is also being made available in conjunction with a website for evaluating the automated analysis of the testing data.
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BACKGROUND: Trans-synaptic degeneration (TSD) describes the propagation of neuronal injury through synaptic pathways in the human nervous system and may be linked to the accelerated retinal atrophy seen in multiple sclerosis (MS). RESULTS: We report six cases where homonymous, hemi-macular ganglion cell + inner plexiform (GCIP) thickness reduction was seen in conjunction with posterior visual pathway lesions. Macular microcystoid changes of the inner nuclear layer (INL) were seen in a subset of three subjects. CONCLUSION: Our findings highlight the utility of assessing regional GCIP changes to identify potential retrograde TSD in MS and demonstrate that INL changes may be an accompaniment in such instances.
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Imagen por Resonancia Magnética , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Células Ganglionares de la Retina/patología , Degeneración Retrógrada , Sinapsis/patología , Tomografía de Coherencia Óptica , Vías Visuales/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/patología , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Valor Predictivo de las Pruebas , Visión Ocular , Vías Visuales/patología , Vías Visuales/fisiopatologíaRESUMEN
In conjunction with the ISBI 2015 conference, we organized a longitudinal lesion segmentation challenge providing training and test data to registered participants. The training data consisted of five subjects with a mean of 4.4 time-points, and test data of fourteen subjects with a mean of 4.4 time-points. All 82 data sets had the white matter lesions associated with multiple sclerosis delineated by two human expert raters. Eleven teams submitted results using state-of-the-art lesion segmentation algorithms to the challenge, with ten teams presenting their results at the conference. We present a quantitative evaluation comparing the consistency of the two raters as well as exploring the performance of the eleven submitted results in addition to three other lesion segmentation algorithms. The challenge presented three unique opportunities: (1) the sharing of a rich data set; (2) collaboration and comparison of the various avenues of research being pursued in the community; and (3) a review and refinement of the evaluation metrics currently in use. We report on the performance of the challenge participants, as well as the construction and evaluation of a consensus delineation. The image data and manual delineations will continue to be available for download, through an evaluation website2 as a resource for future researchers in the area. This data resource provides a platform to compare existing methods in a fair and consistent manner to each other and multiple manual raters.
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Esclerosis Múltiple/diagnóstico por imagen , Adulto , Algoritmos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Sustancia Blanca/diagnóstico por imagenRESUMEN
OBJECTIVE: To retrospectively investigate whether disease-modifying therapies (DMTs) exert differential effects on rates of retinal atrophy in relapsing-remitting multiple sclerosis (RRMS), as assessed using optical coherence tomography (OCT). METHODS: A total of 402 patients with RRMS followed at the Johns Hopkins MS Center who underwent Cirrus-HD OCT were assessed for eligibility. Inclusion criteria included at least 1 year of OCT follow-up and adherence to a single DMT during the period of follow-up. Combined thickness of the ganglion cell + inner plexiform (GCIP) and other retinal layers was computed utilizing automated macular segmentation. Retinal thickness changes were analyzed using mixed-effects linear regression. RESULTS: The effects of glatiramer acetate (GA; n = 48), natalizumab (NAT; n = 46), and interferon-ß-1a subcutaneously (IFNSC; n = 35) and intramuscularly (IFNIM; n = 28) were assessed. Baseline analyses revealed no significant differences between groups in terms of age, sex, optic neuritis history, or follow-up duration. During follow-up, relative to NAT-treated patients, IFNSC- and GA-treated patients exhibited 0.37 µm/y (p < 0.001) and 0.14 µm/y (p = 0.035) faster rates of GCIP thinning, respectively, adjusting for the interval between initiation of DMT and OCT monitoring (gap time), age, sex, relapses, and disease duration. In the IFNSC group, GCIP thinning was 1.53 µm/y faster during the first year of therapy vs during the time interval afterwards (p < 0.001). CONCLUSIONS: Rates of GCIP atrophy in patients with RRMS vary according to DMT utilization. Our findings support OCT for monitoring neurodegenerative treatment effects in the retina, an easily accessible tissue, and as a practical outcome measure in RRMS clinical trials.
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Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Degeneración Retiniana/diagnóstico por imagen , Degeneración Retiniana/tratamiento farmacológico , Adulto , Atrofia , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Acetato de Glatiramer/uso terapéutico , Humanos , Factores Inmunológicos/uso terapéutico , Interferón beta-1a/administración & dosificación , Modelos Lineales , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/complicaciones , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Natalizumab/uso terapéutico , Tamaño de los Órganos , Retina/diagnóstico por imagen , Retina/efectos de los fármacos , Degeneración Retiniana/etiología , Degeneración Retiniana/fisiopatología , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Resultado del TratamientoRESUMEN
BACKGROUND: Retinal atrophy in multiple sclerosis (MS) is secondary to optic nerve focal inflammation and to injury of the posterior visual pathway. OBJECTIVES: To investigate the contribution of cortical lesions (CLs) to retinal pathology in primary-progressive multiple sclerosis (PPMS). METHODS: We performed a cross-sectional evaluation of 25 patients and 20 controls, relating magnetic resonance imaging (MRI) metrics of visual pathway integrity with parameters derived from spectral-domain optical coherence tomography (peripapillary retinal nerve fiber layer (RNFL) thickness, ganglion cell + inner plexiform layer (GCIPL) thickness, and macular volume (MV)). RESULTS: Mean RNFL, GCIPL thickness, and MV were significantly reduced in patients compared to controls. MV and GCIPL thickness were significantly correlated with visual acuity. RNFL thinning was associated with thalamus and visual cortex volume (respectively, p = 0.01 and p < 0.05). In addition to thalamic volume, GCIPL thinning was associated with CLs and intracortical lesion number and volume, leucocortical lesion volume (all p ⩽ 0.05) while MV decrease was associated with CLs volume ( p = 0.05) and intracortical lesion number and volume ( p < 0.05). CONCLUSION: Our results suggest that RNFL thinning and GCIPL thinning/MV decrease may be explained by alternative mechanisms including retrograde trans-synaptic degeneration and/or a common pathophysiologic process affecting both the brain with CLs and the retina with neuronal loss.
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Esclerosis Múltiple Crónica Progresiva/diagnóstico por imagen , Fibras Nerviosas/patología , Retina/patología , Degeneración Retiniana/diagnóstico por imagen , Células Ganglionares de la Retina/patología , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Crónica Progresiva/complicaciones , Esclerosis Múltiple Crónica Progresiva/patología , Neuritis Óptica/patología , Degeneración Retiniana/etiología , Degeneración Retiniana/patología , Degeneración Retiniana/fisiopatología , Vías Visuales/patologíaRESUMEN
Activation of oncogenes by mechanisms other than genetic aberrations such as mutations, translocations, or amplifications is largely undefined. Here we report a novel isoform of the anaplastic lymphoma kinase (ALK) that is expressed in â¼11% of melanomas and sporadically in other human cancer types, but not in normal tissues. The novel ALK transcript initiates from a de novo alternative transcription initiation (ATI) site in ALK intron 19, and was termed ALK(ATI). In ALK(ATI)-expressing tumours, the ATI site is enriched for H3K4me3 and RNA polymerase II, chromatin marks characteristic of active transcription initiation sites. ALK(ATI) is expressed from both ALK alleles, and no recurrent genetic aberrations are found at the ALK locus, indicating that the transcriptional activation is independent of genetic aberrations at the ALK locus. The ALK(ATI) transcript encodes three proteins with molecular weights of 61.1, 60.8 and 58.7 kilodaltons, consisting primarily of the intracellular tyrosine kinase domain. ALK(ATI) stimulates multiple oncogenic signalling pathways, drives growth-factor-independent cell proliferation in vitro, and promotes tumorigenesis in vivo in mouse models. ALK inhibitors can suppress the kinase activity of ALK(ATI), suggesting that patients with ALK(ATI)-expressing tumours may benefit from ALK inhibitors. Our findings suggest a novel mechanism of oncogene activation in cancer through de novo alternative transcription initiation.
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Regulación Neoplásica de la Expresión Génica/genética , Neoplasias/enzimología , Neoplasias/genética , Proteínas Tirosina Quinasas Receptoras/genética , Iniciación de la Transcripción Genética , Alelos , Quinasa de Linfoma Anaplásico , Animales , Línea Celular Tumoral , Proliferación Celular , Transformación Celular Neoplásica , Femenino , Células HEK293 , Histonas/química , Histonas/metabolismo , Humanos , Intrones/genética , Isoenzimas/antagonistas & inhibidores , Isoenzimas/biosíntesis , Isoenzimas/química , Isoenzimas/genética , Lisina/metabolismo , Metilación , Ratones , Datos de Secuencia Molecular , Peso Molecular , Células 3T3 NIH , Neoplasias/tratamiento farmacológico , Oncogenes/genética , Estructura Terciaria de Proteína/genética , ARN Polimerasa II/metabolismo , ARN Mensajero/análisis , ARN Mensajero/genética , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/biosíntesis , Proteínas Tirosina Quinasas Receptoras/química , Transducción de SeñalRESUMEN
Innate monocytes and macrophages can be dynamically programmed into distinct states depending upon the strength of external stimuli. Innate programming may bear significant relevance to the pathogenesis and resolution of human inflammatory diseases. However, systems analyses with regard to the dynamic programming of innate leukocytes are lacking. In this study, we focused on the dynamic responses of human promonocytic THP-1 cells to lipopolysaccharide (LPS). We observed that varying dosages of LPS differentially modulate the expression of selected pro- and anti- inflammatory mediators such as IL-6 and IL-33. Super-low dosages of LPS preferentially induced the pro-inflammatory mediator IL-6, while higher dosages of LPS induced both IL-6 and IL-33. Mechanistically, we demonstrated that super-low and high doses of LPS cause differential activation of GSK3 and Akt, as well as the transcription factors FoxO1 and CREB. Inhibition of GSK3 enabled THP-1 cells to express IL-33 when challenged with super-low dose LPS. On the other hand, activation of CREB with adenosine suppressed IL-6 expression. Taken together, our study reveals a dynamic modulation of monocytic cells in response to varying dosages of endotoxin, and may shed light on our understanding of the dynamic balance that controls pathogenesis and resolution of inflammatory diseases.