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1.
Genes Dev ; 38(9-10): 455-472, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38866557

RESUMEN

Monomethylation of lysine 20 of histone H4 (H4K20me1) is catalyzed by Set8 and thought to play important roles in many aspects of genome function that are mediated by H4K20me binding proteins. We interrogated this model in a developing animal by comparing in parallel the transcriptomes of Set8 null , H4 K20R/A , and l(3)mbt mutant Drosophila melanogaster We found that the gene expression profiles of H4 K20A and H4 K20R larvae are markedly different than Set8 null larvae despite similar reductions in H4K20me1. Set8 null mutant cells have a severely disrupted transcriptome and fail to proliferate in vivo, but these phenotypes are not recapitulated by mutation of H4 K20 , indicating that the developmental defects of Set8 null animals are largely due to H4K20me1-independent effects on gene expression. Furthermore, the H4K20me1 binding protein L(3)mbt is recruited to the transcription start sites of most genes independently of H4K20me even though genes bound by L(3)mbt have high levels of H4K20me1. Moreover, both Set8 and L(3)mbt bind to purified H4K20R nucleosomes in vitro. We conclude that gene expression changes in Set8 null and H4 K20 mutants cannot be explained by loss of H4K20me1 or L(3)mbt binding to chromatin and therefore that H4K20me1 does not play a large role in gene expression.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , N-Metiltransferasa de Histona-Lisina , Histonas , Lisina , Animales , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Histonas/metabolismo , Histonas/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Metilación , Lisina/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Regulación del Desarrollo de la Expresión Génica/genética , Mutación , Transcriptoma/genética , Larva/genética , Larva/metabolismo , Larva/crecimiento & desarrollo
2.
J Biol Chem ; 299(8): 105037, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37442235

RESUMEN

The nucleosome is the fundamental gene-packing unit in eukaryotes. Nucleosomes comprise ∼147 bp DNA wrapped around an octameric histone protein core composed of two H2A-H2B dimers and one (H3-H4)2 tetramer. The strong yet flexible DNA-histone interactions are the physical basis of the dynamic regulation of genes packaged in chromatin. The dynamic nature of DNA-histone interactions also implies that nucleosomes dissociate DNA-histone contacts both transiently and repeatedly. This kinetic instability may lead to spontaneous nucleosome disassembly or histone exchange between nucleosomes. At high nucleosome concentrations, nucleosome-nucleosome collisions and subsequent histone exchange would be a more likely event, where nucleosomes could act as their own histone chaperone. This spontaneous histone exchange could serve as a mechanism for maintaining overall chromatin stability, although it has never been reported. Here we employed three-color single-molecule FRET (smFRET) to demonstrate that histone H2A-H2B dimers are exchanged spontaneously between nucleosomes on a time scale of a few tens of seconds at a physiological nucleosome concentration. We show that the rate of histone exchange increases at a higher monovalent salt concentration, with histone-acetylated nucleosomes, and in the presence of histone chaperone Nap1, while it remains unchanged at a higher temperature, and decreases upon DNA methylation. These results support the notion of histone exchange via transient and repetitive partial disassembly of the nucleosome and corroborate spontaneous histone diffusion in a compact chromatin context, modulating the local concentrations of histone modifications and variants.


Asunto(s)
Histonas , Nucleosomas , Histonas/metabolismo , Cromatina , ADN/metabolismo , Chaperonas de Histonas/genética
3.
Methods ; 215: 17-27, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37236433

RESUMEN

The nucleosome is the fundamental building block of chromatin. Changes taking place at the nucleosome level are the molecular basis of chromatin transactions with various enzymes and factors. These changes are directly and indirectly regulated by chromatin modifications such as DNA methylation and histone post-translational modifications including acetylation, methylation, and ubiquitylation. Nucleosomal changes are often stochastic, unsynchronized, and heterogeneous, making it very difficult to monitor with traditional ensemble averaging methods. Diverse single-molecule fluorescence approaches have been employed to investigate the structure and structural changes of the nucleosome in the context of its interactions with various enzymes such as RNA Polymerase II, histone chaperones, transcription factors, and chromatin remodelers. We utilize diverse single-molecule fluorescence methods to study the nucleosomal changes accompanying these processes, elucidate the kinetics of these processes, and eventually learn the implications of various chromatin modifications in directly regulating these processes. The methods include two- and three-color single-molecule fluorescence resonance energy transfer (FRET), single-molecule fluorescence correlation spectroscopy, and fluorescence (co-)localization. Here we report the details of the two- and three-color single-molecule FRET methods we currently use. This report will help researchers design their single-molecule FRET approaches to investigating chromatin regulation at the nucleosome level.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Nucleosomas , Transferencia Resonante de Energía de Fluorescencia/métodos , Histonas/metabolismo , Cromatina/genética , Metilación de ADN
4.
Curr Treat Options Oncol ; 25(5): 605-616, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38573430

RESUMEN

OPINION STATEMENT: The treatment of oligometastatic genitourinary cancers is a rapidly advancing field with ablative radiotherapy as one of the critical treatment components. The oligometastatic disease state, which can be defined as 1-5 metastatic sites with a controlled primary, represents a distinct clinical state where comprehensive ablative local therapies may provide improved outcomes. Enhanced imaging has increased the number of patients identified with oligometastatic disease. Evidence for improved outcomes with metastasis-directed therapy (MDT) in oligometastatic genitourinary cancers is increasing, and previously published outcome data continues to mature with an increasing body of prospective data to inform the role of MDT in histology-specific settings or in the context of systemic therapy. In select patients, MDT can offer benefits beyond improved local control and allow for time off of systemic therapy, prolonged time until next therapy, or even the hope of cure. However, treatment decisions for locally ablative therapy must be balanced with consideration towards safety. There are exciting advances in technologies to target and adapt treatment in real-time which have expanded options for safer delivery and dose escalation to metastatic targets near critical organs at risk. The role of systemic therapies in conjunction with MDT and incorporation of tumor genetic information to further refine prognostication and treatment decision-making in the oligometastatic setting is actively being investigated. These developments highlight the evolving field of treatment of oligometastatic disease. Future prospective studies combining MDT with enhanced imaging and integrating MDT with evolving systemic therapies will enable the optimal selection of patients most likely to benefit from this "all-or-none" approach and reveal settings in which a combination of therapies could result in synergistic outcomes.


Asunto(s)
Metástasis de la Neoplasia , Neoplasias Urogenitales , Humanos , Neoplasias Urogenitales/terapia , Neoplasias Urogenitales/diagnóstico , Neoplasias Urogenitales/patología , Manejo de la Enfermedad , Terapia Combinada/métodos , Resultado del Tratamiento , Toma de Decisiones Clínicas
5.
Soc Psychiatry Psychiatr Epidemiol ; 59(4): 681-694, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37195293

RESUMEN

PURPOSE: The prevalence of parental burnout, a condition that has severe consequences for both parents and children, varies dramatically across countries and is highest in Western countries characterized by high individualism. METHOD: In this study, we examined the mediators of the relationship between individualism measured at the country level and parental burnout measured at the individual level in 36 countries (16,059 parents). RESULTS: The results revealed three mediating mechanisms, that is, self-discrepancies between socially prescribed and actual parental selves, high agency and self-directed socialization goals, and low parental task sharing, by which individualism leads to an increased risk of burnout among parents. CONCLUSION: The results confirm that the three mediators under consideration are all involved, and that mediation was higher for self-discrepancies between socially prescribed and actual parental selves, then parental task sharing, and lastly self-directed socialization goals. The results provide some important indications of how to prevent parental burnout at the societal level in Western countries.


Asunto(s)
Agotamiento Profesional , Padres , Niño , Humanos , Agotamiento Psicológico , Socialización , Agotamiento Profesional/epidemiología
6.
J Stroke Cerebrovasc Dis ; 33(1): 107468, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38039801

RESUMEN

INTRODUCTION: Tenecteplase has been compared to alteplase in acute stroke randomized trials, with similar outcomes and safety measures, but higher doses of tenecteplase have been associated with higher hemorrhage rates in some studies. Limited data are available on the safety of tenecteplase outside of clinical trials. METHODS: We examined the safety measures of intracranial hemorrhage, angioedema, and serious extracranial adverse events in a 21-hospital integrated healthcare system that switched from alteplase (0.9 mg/kg, maximum dose 90 mg) to tenecteplase (0.25 mg/kg, maximum dose 25 mg) for acute ischemic stroke. RESULTS: Among 3,689 subjects, no significant differences were seen between tenecteplase and alteplase in the rate of intracranial hemorrhage (ICH), parenchymal hemorrhage, or volume of parenchymal hemorrhage. Symptomatic hemorrhage (sICH) was not different between the two agents: sICH by NINDS criteria was 2.0 % for alteplase vs 2.3 % for tenecteplase (P = 0.57), and sICH by SITS criteria was 0.8 % vs 1.1 % (P = 0.39). Adjusted logistic regression models also showed no differences between tenecteplase and alteplase: the odds ratio for tenecteplase (vs alteplase) modeling sICH by NINDS criteria was 0.9 (95 % CI 0.33 - 2.46, P = 0.83) and the odds ratio for tenecteplase modeling sICH by SITS criteria was 1.12 (95 % CI 0.25 - 5.07, P = 0.89). Rates of angioedema and serious extracranial adverse events were low and did not differ between tenecteplase and alteplase. Elapsed door-to-needle times showed a small improvement after the switch to tenecteplase (51.8 % treated in under 30 min with tenecteplase vs 43.5 % with alteplase, P < 0.001). CONCLUSION: In use outside of clinical trials, complication rates are similar between tenecteplase and alteplase. In the context of a stroke telemedicine program, the rates of hemorrhage observed with either agent were lower than expected based on prior trials and registry data. The more easily prepared tenecteplase was associated with a lower door-to-needle time.


Asunto(s)
Angioedema , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Activador de Tejido Plasminógeno/efectos adversos , Tenecteplasa/efectos adversos , Fibrinolíticos/efectos adversos , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/inducido químicamente , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/inducido químicamente , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/tratamiento farmacológico , Angioedema/inducido químicamente , Resultado del Tratamiento , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/inducido químicamente
7.
Breast Cancer Res Treat ; 201(1): 117-126, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37326764

RESUMEN

PURPOSE: Studies comparing the effect of aromatase inhibitor (AI) and tamoxifen use on cardiovascular disease (CVD) risk factors in hormone receptor-positive breast cancer (BC) survivors report conflicting results. We examined associations of endocrine therapy use with incident diabetes, dyslipidemia, and hypertension. METHODS: The Pathways Heart Study examines cancer treatment exposures with CVD-related outcomes in Kaiser Permanente Northern California members with BC. Electronic health records provided sociodemographic and health characteristics, BC treatment, and CVD risk factor data. Hazard ratios (HR) and 95% confidence intervals (CI) of incident diabetes, dyslipidemia, and hypertension in hormone receptor-positive BC survivors using AIs or tamoxifen compared with survivors not using endocrine therapy were estimated using Cox proportional hazards regression models adjusted for known confounders. RESULTS: In 8985 BC survivors, mean baseline age and follow-up time was 63.3 and 7.8 years, respectively; 83.6% were postmenopausal. By treatment, 77.0% used AIs, 19.6% used tamoxifen, and 16.0% used neither. Postmenopausal women who used tamoxifen had an increased rate (HR 1.43, 95% CI 1.06-1.92) of developing hypertension relative to those who did not use endocrine therapy. Tamoxifen use was not associated with incident diabetes, dyslipidemia, or hypertension in premenopausal BC survivors. Postmenopausal AI users had higher hazard rates of developing diabetes (HR 1.37, 95% CI 1.05-1.80), dyslipidemia (HR 1.58, 95% CI 1.29-1.92), and hypertension (HR 1.50, 95% CI 1.24-1.82) compared with non-endocrine therapy users. CONCLUSION: Hormone receptor-positive BC survivors treated with AIs may have higher rates of developing diabetes, dyslipidemia, and hypertension over an average 7.8 years post-diagnosis.


Asunto(s)
Neoplasias de la Mama , Hipertensión , Femenino , Humanos , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/epidemiología , Antineoplásicos Hormonales/efectos adversos , Factores de Riesgo Cardiometabólico , Tamoxifeno/efectos adversos , Hipertensión/epidemiología , Inhibidores de la Aromatasa/efectos adversos , Factores de Riesgo
8.
J Vasc Surg ; 78(5): 1239-1247.e4, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37406943

RESUMEN

OBJECTIVE: The results of current prospective trials comparing the effectiveness of carotid endarterectomy (CEA) vs standard medical therapy for long-term stroke prevention in patients with asymptomatic carotid stenosis (ACS) will not be available for several years. In this study, we compared the observed effectiveness of CEA and standard medical therapy vs standard medical therapy alone to prevent ipsilateral stroke in a contemporary cohort of patients with ACS. METHODS: This cohort study was conducted in a large integrated health system in adult subjects with 70% to 99% ACS (no neurologic symptom within 6 months) with no prior ipsilateral carotid artery intervention. Causal inference methods were used to emulate a conceptual randomized trial using data from January 1, 2008, through December 31, 2017, for comparing the event-free survival over 96 months between two treatment strategies: (1) CEA within 12 months from cohort entry vs (2) no CEA (standard medical therapy alone). To account for both baseline and time-dependent confounding, inverse probability weighting estimation was used to derive adjusted hazard ratios, and cumulative risk differences were assessed based on two logistic marginal structural models for counterfactual hazards. Propensity scores were data-adaptively estimated using super learning. The primary outcome was ipsilateral anterior ischemic stroke. RESULTS: The cohort included 3824 eligible patients with ACS (mean age: 73.7 years, 57.9% male, 12.3% active smokers), of whom 1467 underwent CEA in the first year, whereas 2297 never underwent CEA. The median follow-up was 68 months. A total of 1760 participants (46%) died, 445 (12%) were lost to follow-up, and 158 (4%) experienced ipsilateral stroke. The cumulative risk differences for each year of follow-up showed a protective effect of CEA starting in year 2 (risk difference = 1.1%, 95% confidence interval: 0.5%-1.6%) and persisting to year 8 (2.6%, 95% confidence interval: 0.3%-4.8%) compared with patients not receiving CEA. CONCLUSIONS: In this contemporary cohort study of patients with ACS using rigorous analytic methodology, CEA appears to have a small but statistically significant effect on stroke prevention out to 8 years. Further study is needed to appropriately select the subset of patients most likely to benefit from intervention.


Asunto(s)
Estenosis Carotídea , Prestación Integrada de Atención de Salud , Endarterectomía Carotidea , Accidente Cerebrovascular , Humanos , Masculino , Anciano , Femenino , Constricción Patológica/complicaciones , Estudios de Cohortes , Factores de Riesgo , Resultado del Tratamiento , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/terapia , Endarterectomía Carotidea/efectos adversos , Arterias Carótidas , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Medición de Riesgo
9.
J Appl Clin Med Phys ; 24(7): e13965, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36924220

RESUMEN

PURPOSE: The role of biliary stents in image-guided localization for pancreatic cancer has been inconclusive. To date, stent accuracy has been largely evaluated against implanted fiducials on cone beam computed tomography. We aim to use magnetic resonance (MR) soft tissue as a direct reference to examine the geometric and dosimetric impacts of stent-based localization on the newly available MR linear accelerator. METHODS: Thirty pancreatic cancer patients (132 fractions) treated on our MR linear accelerator were identified to have a biliary stent. In our standard adaptive workflow, patients were set up to the target using soft tissue for image registration and structures were re-contoured on daily MR images. The original plan was then projected on treatment anatomy and dose predicted, followed by plan re-optimization and treatment delivery. These online predicted plans were soft tissue-based and served as reference plans. Retrospective image registration to the stent was performed offline to simulate stent-based localization and the magnitude of shifts was taken as the geometric accuracy of stent localization. New predicted plans were generated based on stent-alignment for dosimetric comparison. RESULTS: Shifts were within 3 mm for 90% of the cases (mean = 1.5 mm); however, larger shifts up to 7.2 mm were observed. Average PTV coverage dropped by 1.1% with a maximum drop of 26.8%. The mean increase in V35Gy was 0.15, 0.05, 0.02, and 0.02 cc for duodenum, stomach, small bowel and large bowel, respectively. Stent alignment was significantly worse for all metrics except for small bowel (p = 0.07). CONCLUSIONS: Overall discrepancy between stent- and soft tissue-alignment was modest; however, large discrepancies were observed for select cases. While PTV coverage loss may be compensated for by using a larger margin, the increase in dose to gastrointestinal organs at risk may limit the role of biliary stents in image-guided localization.


Asunto(s)
Neoplasias Pancreáticas , Radiocirugia , Radioterapia Guiada por Imagen , Humanos , Radiocirugia/métodos , Estudios Retrospectivos , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/cirugía , Stents , Espectroscopía de Resonancia Magnética , Planificación de la Radioterapia Asistida por Computador/métodos , Dosificación Radioterapéutica , Radioterapia Guiada por Imagen/métodos , Neoplasias Pancreáticas
10.
Angew Chem Int Ed Engl ; 62(46): e202311669, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37714818

RESUMEN

Parahydrogen-induced polarization (PHIP) followed by polarization transfer to 13 C is a rapidly developing technique for the generation of 13 C-hyperpolarized substrates. Chirality plays an essential role in living systems and differential metabolism of enantiomeric pairs of metabolic substrates is well documented. Inspired by asymmetric hydrogenation, here we report stereoPHIP, which involves the addition of parahydrogen to a prochiral substrate with a chiral catalyst followed by polarization transfer to 13 C spins. We demonstrate that parahydrogen could be rapidly added to the prochiral precursor to both enantiomers of lactic acid (D and L), with both the (R,R) and (S,S) enantiomers of a chiral rhodium(I) catalyst to afford highly 13 C-hyperpolarized (over 20 %) L- and D-lactate ester derivatives, respectively, with excellent stereoselectivity. We also show that the hyperpolarized 1 H signal decays obtained with the (R,R) and (S,S) catalysts were markedly different. StereoPHIP expands the scope of conventional PHIP to the production of 13 C hyperpolarized chiral substrates with high stereoselectivity.

11.
Biochemistry ; 61(20): 2198-2205, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36112542

RESUMEN

Eukaryotic gene compaction takes place at multiple levels to package DNA to chromatin and chromosomes. Two of the most fundamental levels of DNA packaging are at the nucleosome and dinucleosome stacks. The nucleosome is the basic gene-packing unit and is composed of DNA wrapped around a histone core. Nucleosomes stack with one another for further compaction of DNA. The first stacking step leads to dinucleosome formation, which is driven by internucleosomal interactions between various parts of two nucleosomes. Histone proteins are rich targets for post-translational modifications, some of which affect the structure of the nucleosome and the interactions between nucleosomes. These effects are often implicated in the regulation of various genomic transactions. In particular, histone H2B ubiquitylation has been associated with facilitated transcription and hexasome formation. Here, we employed semi-synthetically ubiquitylated histone H2B and single-molecule FRET to investigate the effects of H2B ubiquitylations at lysine 34 (H2BK34) and lysine 120 (H2BK120) on the structure of the nucleosome and the interactions between two nucleosomes. Our results suggest that H2BK34 ubiquitylation widens the DNA gyre gap in the nucleosome and stabilizes long- and short-range internucleosomal interactions while H2BK120 ubiquitylation does not affect the nucleosome structure or internucleosomal interactions. These results suggest potential roles for H2B ubiquitylations in facilitated transcription and hexasome formation while maintaining the structural integrity of chromatin.


Asunto(s)
Histonas , Nucleosomas , Cromatina , ADN/química , Histonas/metabolismo , Lisina/metabolismo , Ubiquitinación
12.
Stroke ; 53(9): 2838-2846, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35674045

RESUMEN

BACKGROUND: Moderate carotid artery stenosis is a poorly defined risk factor for ischemic stroke. As such, practice recommendations are lacking. In this study, we describe the long-term risk of stroke in patients with moderate asymptomatic stenosis in an integrated health care system. METHODS: All adult patients with asymptomatic moderate (50%-69%) internal carotid artery stenosis between 2008 and 2012 were identified, with follow-up through 2017. The primary outcome was acute ischemic stroke attributed to the ipsilateral carotid artery. Stroke rates were calculated using competing risk analysis. Secondary outcomes included disease progression, ipsilateral intervention, and long-term survival. RESULTS: Overall, 11 614 arteries with moderate stenosis in 9803 patients were identified. Mean age was 74.2±9.9 years with 51.4% women. Mean follow-up was 5.1±2.9 years. There were 180 ipsilateral ischemic strokes (1.6%) identified (crude annual risk, 0.31% [95% CI, 0.21%-0.41%]), of which thirty-one (17.2%) underwent subsequent intervention. Controlling for death and intervention as competing risks, the cumulative incidence of stroke was 1.2% (95% CI, 1.0%-1.4%) at 5 years and 2.0% (95% CI, 1.7%-2.4%) at 10 years. Of identified strokes, 50 (27.8%) arteries had progressed to severe stenosis or occlusion. During follow-up, there were 17 029 carotid studies performed in 5951 patients, revealing stenosis progression in 1674 (14.4%) arteries, including 1614 (13.9%) progressing to severe stenosis and 60 (0.5%) to occlusion. The mean time to stenosis progression was 2.6±2.1 years. Carotid intervention occurred in 708 arteries (6.1%). Of these, 66.1% (468/708) had progressed to severe stenosis. The overall mortality rate was 44.5%, with 10.5% of patients lost to follow-up. CONCLUSIONS: In this community-based sample of patients with asymptomatic moderate internal carotid artery stenosis followed for an average of 5 years, the cumulative incidence of stroke is low out to 10 years. Future research is needed to optimize management strategies for this population.


Asunto(s)
Estenosis Carotídea , Endarterectomía Carotidea , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Adulto , Anciano , Anciano de 80 o más Años , Arteria Carótida Interna , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/epidemiología , Constricción Patológica/complicaciones , Progresión de la Enfermedad , Endarterectomía Carotidea/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/etiología
13.
JAMA ; 327(20): 1974-1982, 2022 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-35608581

RESUMEN

Importance: Optimal management of patients with asymptomatic severe carotid stenosis is uncertain, due to advances in medical care and a lack of contemporary data comparing medical and surgical treatment. Objective: To estimate stroke outcomes among patients with medically treated asymptomatic severe carotid stenosis who did not undergo surgical intervention. Design, Setting, and Participants: Retrospective cohort study that included 3737 adult participants with asymptomatic severe (70%-99%) carotid stenosis diagnosed between 2008 and 2012 and no prior intervention or ipsilateral neurologic event in the prior 6 months. Participants received follow-up through 2019, and all were members of an integrated US regional health system serving 4.5 million members. Exposures: Imaging diagnosis of asymptomatic carotid stenosis of 70% to 99%. Main Outcomes and Measures: Occurrence of ipsilateral carotid-related acute ischemic stroke. Censoring occurred with death, disenrollment, or ipsilateral intervention. Results: Among 94 822 patients with qualifying imaging studies, 4230 arteries in 3737 (mean age, 73.8 [SD 9.5 years]; 57.4% male) patients met selection criteria including 2539 arteries in 2314 patients who never received intervention. The mean follow-up in this cohort was 4.1 years (SD 3.6 years). Prior to any intervention, there were 133 ipsilateral strokes with a mean annual stroke rate of 0.9% (95% confidence interval [CI], 0.7%-1.2%). The Kaplan-Meier estimate of ipsilateral stroke by 5 years was 4.7% (95% CI, 3.9%-5.7%). Conclusions and Relevance: In a community-based cohort of patients with asymptomatic severe carotid stenosis who did not undergo surgical intervention, the estimated rate of ipsilateral carotid-related acute ischemic stroke was 4.7% over 5 years. These findings may inform decision-making regarding surgical and medical treatment for patients with asymptomatic severe carotid artery stenosis.


Asunto(s)
Estenosis Carotídea , Accidente Cerebrovascular Isquémico , Anciano , Anciano de 80 o más Años , Enfermedades Asintomáticas , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/tratamiento farmacológico , Estenosis Carotídea/epidemiología , Estenosis Carotídea/cirugía , Femenino , Humanos , Incidencia , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/etiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología
14.
J Vasc Surg ; 74(6): 1937-1947.e3, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34182027

RESUMEN

OBJECTIVE: Investigation of asymptomatic carotid stenosis treatment is hindered by the lack of a contemporary population-based disease cohort. We describe the use of natural language processing (NLP) to identify stenosis in patients undergoing carotid imaging. METHODS: Adult patients with carotid imaging between 2008 and 2012 in a large integrated health care system were identified and followed through 2017. An NLP process was developed to characterize carotid stenosis according to the Society of Radiologists in Ultrasound (for ultrasounds) and North American Symptomatic Carotid Endarterectomy Trial (NASCET) (for axial imaging) guidelines. The resulting algorithm assessed text descriptors to categorize normal/non-hemodynamically significant stenosis, moderate or severe stenosis as well as occlusion in both carotid ultrasound (US) and axial imaging (computed tomography and magnetic resonance angiography [CTA/MRA]). For US reports, internal carotid artery systolic and diastolic velocities and velocity ratios were assessed and matched for laterality to supplement accuracy. To validate the NLP algorithm, positive predictive value (PPV or precision) and sensitivity (recall) were calculated from simple random samples from the population of all imaging studies. Lastly, all non-normal studies were manually reviewed for confirmation for prevalence estimates and disease cohort assembly. RESULTS: A total of 95,896 qualifying index studies (76,276 US and 19,620 CTA/MRA) were identified among 94,822 patients including 1059 patients who underwent multiple studies on the same day. For studies of normal/non-hemodynamically significant stenosis arteries, the NLP algorithm showed excellent performance with a PPV of 99% for US and 96.5% for CTA/MRA. PPV/sensitivity to identify a non-normal artery with correct laterality in the CTA/MRA and US samples were 76.9% (95% confidence interval [CI], 74.1%-79.5%)/93.1% (95% CI, 91.1%-94.8%) and 74.7% (95% CI, 69.3%-79.5%)/94% (95% CI, 90.2%-96.7%), respectively. Regarding cohort assembly, 15,522 patients were identified with diseased carotid artery, including 2674 exhibiting equal bilateral disease. This resulted in a laterality-specific cohort with 12,828 moderate, 5283 severe, and 1895 occluded arteries and 326 diseased arteries with unknown stenosis. During follow-up, 30.1% of these patients underwent 61,107 additional studies. CONCLUSIONS: Use of NLP to detect carotid stenosis or occlusion can result in accurate exclusion of normal/non-hemodynamically significant stenosis disease states with more moderate precision with lesion identification, which can substantially reduce the need for manual review. The resulting cohort allows for efficient research and holds promise for similar reporting in other vascular diseases.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Angiografía por Tomografía Computarizada , Minería de Datos , Angiografía por Resonancia Magnética , Registros Médicos , Procesamiento de Lenguaje Natural , Ultrasonografía Doppler , Enfermedades Asintomáticas , California , Estenosis Carotídea/fisiopatología , Investigación sobre la Eficacia Comparativa , Estudios Transversales , Hemodinámica , Humanos , Clasificación Internacional de Enfermedades , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
15.
J Vasc Surg ; 73(3): 983-991, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32707387

RESUMEN

OBJECTIVE: Informed debate regarding the optimal use of carotid endarterectomy (CEA) for stroke risk reduction requires contemporary assessment of both long-term risk and periprocedural risk. In this study, we report long-term stroke and death risk after CEA in a large integrated health care system. METHODS: All patients with documented severe (70%-99%) stenosis from 2008 to 2012 who underwent CEA were identified and stratified by asymptomatic or symptomatic indication. Those with prior ipsilateral interventions were excluded. Patients were followed up through 2017 for the primary outcomes of any stroke/death within 30 days of intervention and long-term ipsilateral ischemic stroke; secondary outcomes were any stroke and overall survival. RESULTS: Overall, 1949 patients (63.2% male; mean age, 71.3 ± 8.9 years) underwent 2078 primary CEAs, 1196 (58%) for asymptomatic stenosis and 882 (42%) for symptomatic stenosis. Mean follow-up was 5.5 ± 2.7 years. Median time to surgery was 72.0 (interquartile range, 38.5-198.0) days for asymptomatic patients and 21.0 (interquartile range, 5.0-55.0) days for symptomatic patients (P < .001). Most of the patients' demographics and characteristics were similar in both groups. Controlled blood pressure rates were similar at the time of CEA. Baseline statin use was seen in 60.5% of the asymptomatic group compared with 39.9% in the symptomatic group (P < .001), and statin adherence by 80% medication possession ratio was 19.3% asymptomatic vs 12.4% symptomatic (P < .001). The crude overall 30-day any stroke/death rates were 0.9% and 1.5% for the asymptomatic group and the symptomatic group, respectively. The 5-year risk of ipsilateral stroke and a combined end point of any stroke/death by Kaplan-Meier survival analysis were 2.5% and 28.7% for the asymptomatic group and 4.0% and 31.4% for the symptomatic group, respectively. Unadjusted cumulative all-cause survival was 74.2% for the asymptomatic group and 71.8% for the symptomatic group at 5 years. CONCLUSIONS: In a contemporary review of CEA, outcomes for either operative indication show low adverse events perioperatively and low long-term stroke risk up to 5 years. These results are well within consensus guidelines and published trial outcomes and should help inform the discussion around optimal CEA use for severe carotid stenosis.


Asunto(s)
Estenosis Carotídea/cirugía , Endarterectomía Carotidea/efectos adversos , Accidente Cerebrovascular/etiología , Anciano , Anciano de 80 o más Años , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/mortalidad , Bases de Datos Factuales , Endarterectomía Carotidea/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/mortalidad , Factores de Tiempo , Resultado del Tratamiento
16.
Support Care Cancer ; 29(7): 3707-3714, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33196866

RESUMEN

PURPOSE: While the 0-10 pain scale is often used to assess treatment response, it may not accurately reflect change in pain over time. The purpose of this study is to correlate pain improvement using the 0-10 pain scale to patients' perceived improvement in pain following palliative radiation therapy (RT), and to qualitatively characterize themes of pain assessment. METHODS: Patients age ≥ 20 receiving RT for spinal metastases were enrolled. Patients rated their pain (0-10) at the treatment site at RT start, and 1 and 4 weeks post-RT completion. At 1 and 4 weeks post-RT, patients reported their perceived percent improvement in pain (pPIP) (0-100%), which was compared to calculated percent improvement in pain (cPIP) based on the 0-10 pain scores. At 4 weeks post-RT, 20 randomly selected patients participated in a qualitative pain assessment. RESULTS: Sixty-four patients treated at 1-2 sites were analyzed. At 1 week post-RT completion, 53.7% (36/67) reported pPIP within 10 percentage points of cPIP, 32.8% (22/67) reported pPIP > 10 percentage points higher than cPIP, and 13.4% (9/67) reported pPIP > 10 percentage points lower than cPIP. Similar degrees of discordance were seen at 4 weeks post-RT. Qualitative analysis revealed five themes: pain quality (n = 19), activities (n = 9), function (n = 7), medication use (n = 2), and radiation side effects (n = 1). CONCLUSIONS: About half of patients reported a pPIP substantially disparate from their cPIP, and the change in pain measured by the 0-10 scale tended to underestimate the degree of perceived pain improvement. Multiple themes were identified in qualitative analysis of pain response.


Asunto(s)
Neoplasias/radioterapia , Dimensión del Dolor/métodos , Dolor/inducido químicamente , Cuidados Paliativos/métodos , Medición de Resultados Informados por el Paciente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Investigación Cualitativa
17.
Stroke ; 51(11): 3425-3432, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33104466

RESUMEN

Systemic racism is a public health crisis. Systemic racism and racial/ethnic injustice produce racial/ethnic disparities in health care and health. Substantial racial/ethnic disparities in stroke care and health exist and result predominantly from unequal treatment. This special report aims to summarize selected interventions to reduce racial/ethnic disparities in stroke prevention and treatment. It reviews the social determinants of health and the determinants of racial/ethnic disparities in care. It provides a focused summary of selected interventions aimed at reducing stroke risk factors, increasing awareness of stroke symptoms, and improving access to care for stroke because these interventions hold the promise of reducing racial/ethnic disparities in stroke death rates. It also discusses knowledge gaps and future directions.


Asunto(s)
Asistencia Sanitaria Culturalmente Competente , Diabetes Mellitus/terapia , Disparidades en el Estado de Salud , Disparidades en Atención de Salud , Hipertensión/prevención & control , Racismo , Accidente Cerebrovascular/etnología , Negro o Afroamericano , Dietoterapia , Ejercicio Físico , Educación en Salud/métodos , Conocimientos, Actitudes y Práctica en Salud , Accesibilidad a los Servicios de Salud , Hispánicos o Latinos , Humanos , Hipertensión/terapia , Pueblos Indígenas , Prejuicio , Prevención Primaria , Calidad de la Atención de Salud , Conducta de Reducción del Riesgo , Prevención Secundaria , Automanejo , Determinantes Sociales de la Salud , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/terapia , Tiempo de Tratamiento , Estados Unidos
18.
Stroke ; 51(10): 2918-2924, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32762619

RESUMEN

BACKGROUND AND PURPOSE: Shelter-in-place (SIP) orders implemented to mitigate severe acute respiratory syndrome coronavirus 2 spread may inadvertently discourage patient care-seeking behavior for critical conditions like acute ischemic stroke. We aimed to compare temporal trends in volume of acute stroke alerts, patient characteristics, telestroke care, and short-term outcomes pre- and post-SIP orders. METHODS: We conducted a cohort study in 21 stroke centers of an integrated healthcare system serving 4.4+ million members across Northern California. We included adult patients who presented with suspected acute stroke and were evaluated by telestroke between January 1, 2019, and May 9, 2020. SIP orders announced the week of March 15, 2020, created pre (January 1, 2019, to March 14, 2020) and post (March 15, 2020, to May 9, 2020) cohort for comparison. Main outcomes were stroke alert volumes and inpatient mortality for stroke. RESULTS: Stroke alert weekly volume post-SIP (mean, 98 [95% CI, 92-104]) decreased significantly compared with pre-SIP (mean, 132 [95% CI, 130-136]; P<0.001). Stroke discharges also dropped, in concordance with acute stroke alerts decrease. In total, 9120 patients were included: 8337 in pre- and 783 in post-SIP cohorts. There were no differences in patient demographics. Compared with pre-SIP, post-SIP patients had higher National Institutes of Health Stroke Scale scores (P=0.003), lower comorbidity score (P<0.001), and arrived more often by ambulance (P<0.001). Post-SIP, more patients had large vessel occlusions (P=0.03), and there were fewer stroke mimics (P=0.001). Discharge outcomes were similar for post-SIP and pre-SIP cohorts. CONCLUSIONS: In this cohort study, regional stroke alert and ischemic stroke discharge volumes decreased significantly in the early COVID-19 pandemic. Compared with pre-SIP, the post-SIP population showed no significant demographic differences but had lower comorbidity scores, more severe strokes, and more large vessel occlusions. The inpatient mortality was similar in both cohorts. Further studies are needed to understand the causes and implications of care avoidance to patients and healthcare systems.


Asunto(s)
Infecciones por Coronavirus , Mortalidad Hospitalaria , Hospitales Comunitarios , Pandemias , Neumonía Viral , Accidente Cerebrovascular/epidemiología , Telemedicina , Adulto , Anciano , Anciano de 80 o más Años , Ambulancias , Fibrilación Atrial/epidemiología , Betacoronavirus , COVID-19 , California/epidemiología , Estudios de Cohortes , Comorbilidad , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Aceptación de la Atención de Salud , Alta del Paciente , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/terapia , Resultado del Tratamiento
19.
Stroke ; 51(9): 2697-2704, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32757749

RESUMEN

BACKGROUND AND PURPOSE: In large artery occlusion stroke, both intravenous (IV) tPA (tissue-type plasminogen activator) and endovascular stroke treatment (EST) are standard-of-care. It is unknown how often tPA causes distal embolization, in which a procedurally accessible large artery occlusion is converted to a more distal and potentially inaccessible occlusion. METHODS: We analyzed data from a decentralized stroke telemedicine program in an integrated healthcare delivery system covering 21 hospitals, with 2 high-volume EST centers. We captured all cases sent for EST and examined the relationship between IV tPA administration and the rate of distal embolization, the rate of target recanalization (modified Treatment in Cerebral Infarction scale 2b/3), clinical improvement before EST, and short-term and long-term clinical outcomes. RESULTS: Distal embolization before EST was quite common (63/314 [20.1%]) and occurred more often after IV tPA before EST (57/229 [24.9%]) than among those not receiving IV tPA (6/85 [7.1%]; P<0.001). Distal embolization was associated with an inability to attempt EST: after distal embolization, 26/63 (41.3%) could not have attempted EST because of the new clot location, while in cases without distal embolization, only 8/249 (3.2%) were unable to have attempted EST (P<0.001). Among patients who received IV tPA, 13/242 (5.4%) had sufficient symptom improvement that a catheter angiogram was not performed; 6/342 (2.5%) had improvement to within 2 points of their baseline NIHSS. At catheter angiogram, 2/229 (0.9%) of patients who had received tPA had complete recanalization without distal embolization. Both IV tPA and EST recanalization were associated with improved long-term outcome. CONCLUSIONS: IV tPA administration before EST for large artery occlusion is associated with distal embolization, which in turn may reduce the chance that EST can be attempted and recanalization achieved. At the same time, some IV tPA-treated patients show symptomatic improvement and complete recanalization. Because IV tPA is associated with both distal embolization and improved long-term clinical outcome, there is a need for prospective clinical trials testing the net benefit or harm of IV tPA before EST.


Asunto(s)
Embolización Terapéutica/efectos adversos , Procedimientos Endovasculares/métodos , Fibrinolíticos/efectos adversos , Accidente Cerebrovascular/cirugía , Activador de Tejido Plasminógeno/efectos adversos , Anciano , Anciano de 80 o más Años , Angiografía , Arteriopatías Oclusivas/complicaciones , Infarto Cerebral/cirugía , Femenino , Fibrinolíticos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Activador de Tejido Plasminógeno/uso terapéutico , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
J Antimicrob Chemother ; 74(3): 561-570, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30629197

RESUMEN

OBJECTIVES: To investigate the risk of colonization with ESBL-producing Escherichia coli (ESBL-Ec) in humans in Vietnam associated with non-intensive chicken farming. METHODS: Faecal samples from 204 randomly selected farmers and their chickens, and from 306 age- and sex-matched community-based individuals who did not raise poultry were collected. Antimicrobial usage in chickens and humans was assessed by medicine cabinet surveys. WGS was employed to obtain a high-resolution genomic comparison between ESBL-Ec isolated from humans and chickens. RESULTS: The adjusted prevalence of ESBL-Ec colonization was 20.0% (95% CI 10.8%-29.1%) and 35.2% (95% CI 30.4%-40.1%) in chicken farms and humans in Vietnam, respectively. Colonization with ESBL-Ec in humans was associated with antimicrobial usage (OR = 2.52, 95% CI = 1.08-5.87) but not with involvement in chicken farming. blaCTX-M-55 was the most common ESBL-encoding gene in strains isolated from chickens (74.4%) compared with blaCTX-M-27 in human strains (47.0%). In 3 of 204 (1.5%) of the farms, identical ESBL genes were detected in ESBL-Ec isolated from farmers and their chickens. Genomic similarity indicating recent sharing of ESBL-Ec between chickens and farmers was found in only one of these farms. CONCLUSIONS: The integration of epidemiological and genomic data in this study has demonstrated a limited contribution of non-intensive chicken farming to ESBL-Ec colonization in humans in Vietnam and further emphasizes the importance of reducing antimicrobial usage in both human and animal host reservoirs.


Asunto(s)
Portador Sano/microbiología , Pollos/microbiología , Infecciones por Escherichia coli/transmisión , Escherichia coli/clasificación , Heces/microbiología , Zoonosis/transmisión , beta-Lactamasas/metabolismo , Adulto , Crianza de Animales Domésticos , Animales , Escherichia coli/enzimología , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Femenino , Genoma Bacteriano , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Prevalencia , Medición de Riesgo , Vietnam/epidemiología , Secuenciación Completa del Genoma , Zoonosis/microbiología
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