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1.
Proc Natl Acad Sci U S A ; 121(17): e2318596121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38621142

RESUMEN

While there is increasing recognition that social processes in cities like gentrification have ecological consequences, we lack nuanced understanding of the ways gentrification affects urban biodiversity. We analyzed a large camera trap dataset of mammals (>500 g) to evaluate how gentrification impacts species richness and community composition across 23 US cities. After controlling for the negative effect of impervious cover, gentrified parts of cities had the highest mammal species richness. Change in community composition was associated with gentrification in a few cities, which were mostly located along the West Coast. At the species level, roughly half (11 of 21 mammals) had higher occupancy in gentrified parts of a city, especially when impervious cover was low. Our results indicate that the impacts of gentrification extend to nonhuman animals, which provides further evidence that some aspects of nature in cities, such as wildlife, are chronically inaccessible to marginalized human populations.


Asunto(s)
Biodiversidad , Segregación Residencial , Animales , Humanos , Ciudades , Mamíferos , Animales Salvajes , Ecosistema
2.
Stroke ; 55(1): 31-39, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134265

RESUMEN

BACKGROUND: Quantitative susceptibility mapping (QSM) and dynamic contrast-enhanced quantitative perfusion (DCEQP) magnetic resonance imaging sequences assessing iron deposition and vascular permeability were previously correlated with new hemorrhage in cerebral cavernous malformations. We assessed their prospective changes in a multisite trial-readiness project. METHODS: Patients with cavernous malformation and symptomatic hemorrhage (SH) in the prior year, without prior or planned lesion resection or irradiation were enrolled. Mean QSM and DCEQP of the SH lesion were acquired at baseline and at 1- and 2-year follow-ups. Sensitivity and specificity of biomarker changes were analyzed in relation to predefined criteria for recurrent SH or asymptomatic change. Sample size calculations for hypothesized therapeutic effects were conducted. RESULTS: We logged 143 QSM and 130 DCEQP paired annual assessments. Annual QSM change was greater in cases with SH than in cases without SH (P=0.019). Annual QSM increase by ≥6% occurred in 7 of 7 cases (100%) with recurrent SH and in 7 of 10 cases (70%) with asymptomatic change during the same epoch and 3.82× more frequently than clinical events. DCEQP change had lower sensitivity for SH and asymptomatic change than QSM change and greater variance. A trial with the smallest sample size would detect a 30% difference in QSM annual change during 2 years of follow-up in 34 or 42 subjects (1 and 2 tailed, respectively); power, 0.8, α=0.05. CONCLUSIONS: Assessment of QSM change is feasible and sensitive to recurrent bleeding in cavernous malformations. Evaluation of an intervention on QSM percent change may be used as a time-averaged difference between 2 arms using a repeated measures analysis. DCEQP change is associated with lesser sensitivity and higher variability than QSM. These results are the basis of an application for certification by the US Food and Drug Administration of QSM as a biomarker of drug effect on bleeding in cavernous malformations. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03652181.


Asunto(s)
Hemangioma Cavernoso del Sistema Nervioso Central , Hemorragia , Humanos , Estudios Prospectivos , Hemorragia/etiología , Hemorragia/complicaciones , Hemangioma Cavernoso del Sistema Nervioso Central/complicaciones , Hemangioma Cavernoso del Sistema Nervioso Central/diagnóstico por imagen , Hemangioma Cavernoso del Sistema Nervioso Central/patología , Biomarcadores , Imagen por Resonancia Magnética/métodos , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/complicaciones
3.
Mol Biol Evol ; 40(3)2023 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-36790822

RESUMEN

Genomic regions under positive selection harbor variation linked for example to adaptation. Most tools for detecting positively selected variants have computational resource requirements rendering them impractical on population genomic datasets with hundreds of thousands of individuals or more. We have developed and implemented an efficient haplotype-based approach able to scan large datasets and accurately detect positive selection. We achieve this by combining a pattern matching approach based on the positional Burrows-Wheeler transform with model-based inference which only requires the evaluation of closed-form expressions. We evaluate our approach with simulations, and find it to be both sensitive and specific. The computational resource requirements quantified using UK Biobank data indicate that our implementation is scalable to population genomic datasets with millions of individuals. Our approach may serve as an algorithmic blueprint for the era of "big data" genomics: a combinatorial core coupled with statistical inference in closed form.


Asunto(s)
Genética de Población , Metagenómica , Genómica , Genoma , Haplotipos
4.
Circ Res ; 130(3): 326-338, 2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-34923853

RESUMEN

BACKGROUND: Coronary endothelial dysfunction (CED) causes angina/ischemia in patients with nonobstructive coronary artery disease (NOCAD). Patients with CED have decreased number and function of CD34+ cells involved in normal vascular repair with microcirculatory regenerative potential and paracrine anti-inflammatory effects. We evaluated safety and potential efficacy of intracoronary autologous CD34+ cell therapy for CED. METHODS: Twenty NOCAD patients with invasively diagnosed CED and persistent angina despite maximally tolerated medical therapy underwent baseline exercise stress test, GCSF (granulocyte colony stimulating factor)-mediated CD34+ cell mobilization, leukapheresis, and selective 1×105 CD34+ cells/kg infusion into left anterior descending. Invasive CED evaluation and exercise stress test were repeated 6 months after cell infusion. Primary end points were safety and effect of intracoronary autologous CD34+ cell therapy on CED at 6 months of follow-up. Secondary end points were change in Canadian Cardiovascular Society angina class, as-needed sublingual nitroglycerin use/day, Seattle Angina Questionnaire scores, and exercise time at 6 months. Change in CED was compared with that of 51 historic control NOCAD patients treated with maximally tolerated medical therapy alone. RESULTS: Mean age was 52±13 years; 75% were women. No death, myocardial infarction, or stroke occurred. Intracoronary CD34+ cell infusion improved microvascular CED (%acetylcholine-mediated coronary blood flow increased from 7.2 [-18.0 to 32.4] to 57.6 [16.3-98.3]%; P=0.014), decreased Canadian Cardiovascular Society angina class (3.7±0.5 to 1.7±0.9, Wilcoxon signed-rank test, P=0.00018), and sublingual nitroglycerin use/day (1 [0.4-3.5] to 0 [0-1], Wilcoxon signed-rank test, P=0.00047), and improved all Seattle Angina Questionnaire scores with no significant change in exercise time at 6 months of follow-up. Historic control patients had no significant change in CED. CONCLUSIONS: A single intracoronary autologous CD34+ cell infusion was safe and may potentially be an effective disease-modifying therapy for microvascular CED in humans. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03471611.


Asunto(s)
Angina de Pecho/terapia , Antígenos CD34/metabolismo , Enfermedad de la Arteria Coronaria/terapia , Leucaféresis/métodos , Linfocitos T/trasplante , Adulto , Anciano , Angina de Pecho/etiología , Antígenos CD34/genética , Enfermedad de la Arteria Coronaria/complicaciones , Endotelio Vascular/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linfocitos T/metabolismo , Trasplante Autólogo
5.
Arterioscler Thromb Vasc Biol ; 43(5): 774-783, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36951061

RESUMEN

BACKGROUND: Clonal hematopoiesis (CH) of indeterminate potential (CHIP) is a risk factor for cardiovascular disease. The relationship between CHIP and coronary microvascular dysfunction (CMD) is unknown. The current study examines the association between CHIP and CH with CMD and the potential relationships in risk for adverse cardiovascular outcomes. METHODS: In this retrospective observational study, targeted next-generation sequencing was performed for 177 participants with no coronary artery disease who presented with chest pain and underwent routine coronary functional angiogram. Patients with somatic mutations in leukemia-associated driver genes in hematopoietic stem and progenitor cells were examined; CHIP was considered at a variant allele fraction ≥2%; CH was considered at a variant allele fraction ≥1%. CMD was defined as coronary flow reserve to intracoronary adenosine of ≤2. Major adverse cardiovascular events considered were myocardial infarction, coronary revascularization, or stroke. RESULTS: A total of 177 participants were examined. Mean follow-up was 12±7 years. A total of 17 patients had CHIP and 28 had CH. Cases with CMD (n=19) were compared with controls with no CMD (n=158). Cases were 56±9 years, were 68% women, and had more CHIP (27%; P=0.028) and CH (42%; P=0.001) than controls. CMD was associated with independent risk for major adverse cardiovascular events (hazard ratio, 3.89 [95% CI, 1.21-12.56]; P=0.023), and 32% of this risk was mediated by CH. The risk mediated by CH was ≈0.5× as large as the direct effect of CMD on major adverse cardiovascular events. CONCLUSIONS: In humans, we observe patients with CMD are more likely to have CHIP, and nearly one-third of major adverse cardiovascular events in CMD are mediated by CH.


Asunto(s)
Enfermedad de la Arteria Coronaria , Infarto del Miocardio , Isquemia Miocárdica , Humanos , Femenino , Masculino , Hematopoyesis Clonal/genética , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/genética , Arterias
6.
Neurosurg Rev ; 47(1): 40, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200247

RESUMEN

Intraventricular hemorrhage (IVH) is a complication of a spontaneous intracerebral hemorrhage. Standard treatment is with external ventricular drain (EVD). Intraventricular thrombolysis may improve mortality but does not improve functional outcomes. We present our initial experience with a novel irrigating EVD (IRRAflow) that automates continuous irrigation with thrombolysis.Single-center case-control study including patients with IVH treated with EVD compared to IRRAflow. We compared standard demographics, treatment, and outcome parameters between groups. We developed a brain phantom injected with a human clot and assessed clot clearance using EVD/IRRAflow approaches with CT imaging.Twenty-one patients were treated with standard EVD and 9 patients with IRRAflow. Demographics were similar between groups. Thirty-three percent of patients with EVD also had at least one dose of t-PA and 89% of patients with IRRAflow received irrigation with t-PA (p = 0.01). Mean drain days were 8.8 for EVD versus 4.1 for IRRAflow (p = 0.02). Days-to-clearance of ventricular outflow was 5.8 for EVD versus 2.5 for IRRAflow (p = 0.02). Overall clearance was not different. Thirty-seven percent of EVD patients achieved good outcome (mRS ≥ 3) at 90 days versus 86% of IRRAflow patients (p = 0.03). Assessing only t-PA, reduction in mean days-to-clearance (p = 0.0004) and ICU days (p = 0.04) was observed. In the benchtop model, the clot treated with IRRAflow and t-PA showed a significant reduction of volume compared to control.Irrigation with IRRAflow and t-PA is feasible and safe for patients with IVH. Improving clot clearance with IRRAflow may result in improved clinical outcomes and should be incorporated into randomized trials.


Asunto(s)
Hemorragia Cerebral , Fibrinolíticos , Humanos , Estudios de Casos y Controles , Fibrinolíticos/uso terapéutico , Hemorragia Cerebral/tratamiento farmacológico , Hemorragia Cerebral/cirugía , Encéfalo
7.
Small ; 19(20): e2207805, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36811150

RESUMEN

Photosynthetic light harvesting requires efficient energy transfer within dynamic networks of light-harvesting complexes embedded within phospholipid membranes. Artificial light-harvesting models are valuable tools for understanding the structural features underpinning energy absorption and transfer within chromophore arrays. Here, a method for attaching a protein-based light-harvesting model to a planar, fluid supported lipid bilayer (SLB) is developed.  The protein model consists of the tobacco mosaic viral capsid proteins that are gene-doubled to create a tandem dimer (dTMV). Assemblies of dTMV break the facial symmetry of the double disk to allow for differentiation between the disk faces. A single reactive lysine residue is incorporated into the dTMV assemblies for the site-selective attachment of chromophores for light absorption. On the opposing dTMV face, a cysteine residue is incorporated for the bioconjugation of a peptide containing a polyhistidine tag for association with SLBs. The dual-modified dTMV complexes show significant association with SLBs and exhibit mobility on the bilayer. The techniques used herein offer a new method for protein-surface attachment and provide a platform for evaluating excited state energy transfer events in a dynamic, fully synthetic artificial light-harvesting system.


Asunto(s)
Fotosíntesis , Proteínas , Transferencia de Energía , Membrana Dobles de Lípidos/química
8.
Stroke ; 53(5): 1510-1515, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35331007

RESUMEN

BACKGROUND: Benefit from blood glucose (BG) control during acute ischemic stroke may depend on glycemic parameters. We evaluated for associations between the SHINE (Stroke Hyperglycemia Insulin Network Effort) randomized treatment group and the SHINE predefined 90-day functional outcome, within-patient subgroups defined by various glycemic parameters. METHODS: The SHINE Trial randomized 1151 patients within 12 hours with acute ischemic stroke and hyperglycemia to standard (target BG 80-179 mg/dL) or intensive (target BG 80-130 mg/dL) BG control for 72 hours. We predefined 6 glycemic parameters: acute BG level, absence versus presence of diagnosed and undiagnosed diabetes, hemoglobin A1c, glycemic gap (acute BG-average daily hemoglobin A1c based BG), stress hyperglycemia ratio (acute BG/average daily hemoglobin A1c based BG), and BG variability (SD). Favorable functional outcome was defined by the SHINE Trial and based on the modified Rankin Scale score at 90 days, adjusted for stroke severity. We computed relative risks adjusted for baseline stroke severity and thrombolysis use. RESULTS: Likelihood for favorable outcome was lowest among patients with undiagnosed diabetes compared to patients with true nondiabetes (adjusted relative risk, 0.42 [99% CI, 0.19-0.94]). We did not find any relationship between the favorable outcome rate and baseline BG or any of the glycemic parameters. No differences between SHINE treatment groups were identified among any of these patient subgroups. CONCLUSIONS: In this exploratory subgroup analysis, intensive versus standard insulin treatment of hyperglycemia in acute ischemic stroke patient subgroups, did not influence the 90-day functional outcomes, nor did we identify associations between these glycemic parameters and 90-day functional outcomes.


Asunto(s)
Diabetes Mellitus , Hiperglucemia , Insulinas , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Glucemia , Diabetes Mellitus/epidemiología , Hemoglobina Glucada , Humanos , Hiperglucemia/complicaciones , Hiperglucemia/tratamiento farmacológico , Insulinas/uso terapéutico , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/tratamiento farmacológico
9.
Malar J ; 21(1): 197, 2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35729617

RESUMEN

BACKGROUND: Important knowledge gaps exist in the understanding of the management of the risks of imported malaria in Canada among Francophone immigrants from sub-Saharan Africa (FISSA). The aim of this cross-sectional study was to investigate the malaria related-knowledge, attitude and practices (KAP) of FISSA in Edmonton, where these immigrants are in an official minority language situation and the impact of language barriers on these factors. METHODS: A structured survey was used to examine the KAP of 382 FISSA in the Edmonton area from 2018 to 2019. Fisher's Exact Test was applied to determine if there were associations between knowledge of malaria and different risk factors. RESULTS: Almost all FISSA (97%) had an accurate knowledge of fever as the key symptom of malaria. Interestingly, 60% of participants identified bed nets as a preventive method and only 19% of participants had accurate knowledge of malaria transmission. An accurate knowledge of symptoms was significantly associated with a high perceived risk of contracting malaria [odds ratio (OR) 4.33, 95% confidence interval (CI) 1.07-20.62]. Furthermore, even though 70% of FISSA had a high perceived risk of contracting malaria in endemic regions, only 52% of travellers had a pre-travel medical encounter. Importantly, language was not the predominant reason for not seeking pre-travel medical advice, although 84% of respondents chose French as their official language of preference when seeking medical advice. Having a French-speaking physician was correlated with satisfactory prevention knowledge (OR 1.96, 95% CI 1.16-3.35). With respect to health-seeking behaviour, 88% of respondents with a child < 5 years of age would seek medical care for fever in the child after travel to sub-Saharan Africa (SSA). CONCLUSION: This study highlights that factors other than knowledge, risk assessment, and language might determine the lack of compliance with pre-travel medical encounters. It underscores the need for effective strategies to improve this adherence in minority settings.


Asunto(s)
Emigrantes e Inmigrantes , Malaria , Niño , Estudios Transversales , Fiebre , Conocimientos, Actitudes y Práctica en Salud , Humanos , Malaria/epidemiología , Viaje
10.
Chem Rev ; 120(15): 7919-7983, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32786672

RESUMEN

Brought to life more than half a century ago and successfully applied for high-value petrochemical intermediates production, nickel-catalyzed olefin oligomerization is still a very dynamic topic, with many fundamental questions to address and industrial challenges to overcome. The unique and versatile reactivity of nickel enables the oligomerization of ethylene, propylene, and butenes into a wide range of oligomers that are highly sought-after in numerous fields to be controlled. Interestingly, both homogeneous and heterogeneous nickel catalysts have been scrutinized and employed to do this. This rare specificity encouraged us to interlink them in this review so as to open up opportunities for further catalyst development and innovation. An in-depth understanding of the reaction mechanisms in play is essential to being able to fine-tune the selectivity and achieve efficiency in the rational design of novel catalytic systems. This review thus provides a complete overview of the subject, compiling the main fundamental/industrial milestones and remaining challenges facing homogeneous/heterogeneous approaches as well as emerging catalytic concepts, with a focus on the last 10 years.

11.
N Engl J Med ; 378(8): 708-718, 2018 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-29364767

RESUMEN

BACKGROUND: Thrombectomy is currently recommended for eligible patients with stroke who are treated within 6 hours after the onset of symptoms. METHODS: We conducted a multicenter, randomized, open-label trial, with blinded outcome assessment, of thrombectomy in patients 6 to 16 hours after they were last known to be well and who had remaining ischemic brain tissue that was not yet infarcted. Patients with proximal middle-cerebral-artery or internal-carotid-artery occlusion, an initial infarct size of less than 70 ml, and a ratio of the volume of ischemic tissue on perfusion imaging to infarct volume of 1.8 or more were randomly assigned to endovascular therapy (thrombectomy) plus standard medical therapy (endovascular-therapy group) or standard medical therapy alone (medical-therapy group). The primary outcome was the ordinal score on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability) at day 90. RESULTS: The trial was conducted at 38 U.S. centers and terminated early for efficacy after 182 patients had undergone randomization (92 to the endovascular-therapy group and 90 to the medical-therapy group). Endovascular therapy plus medical therapy, as compared with medical therapy alone, was associated with a favorable shift in the distribution of functional outcomes on the modified Rankin scale at 90 days (odds ratio, 2.77; P<0.001) and a higher percentage of patients who were functionally independent, defined as a score on the modified Rankin scale of 0 to 2 (45% vs. 17%, P<0.001). The 90-day mortality rate was 14% in the endovascular-therapy group and 26% in the medical-therapy group (P=0.05), and there was no significant between-group difference in the frequency of symptomatic intracranial hemorrhage (7% and 4%, respectively; P=0.75) or of serious adverse events (43% and 53%, respectively; P=0.18). CONCLUSIONS: Endovascular thrombectomy for ischemic stroke 6 to 16 hours after a patient was last known to be well plus standard medical therapy resulted in better functional outcomes than standard medical therapy alone among patients with proximal middle-cerebral-artery or internal-carotid-artery occlusion and a region of tissue that was ischemic but not yet infarcted. (Funded by the National Institute of Neurological Disorders and Stroke; DEFUSE 3 ClinicalTrials.gov number, NCT02586415 .).


Asunto(s)
Fibrinolíticos/uso terapéutico , Imagen de Perfusión , Accidente Cerebrovascular/cirugía , Trombectomía , Anciano , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/cirugía , Angiografía Cerebral , Terapia Combinada , Procedimientos Endovasculares , Femenino , Humanos , Masculino , Persona de Mediana Edad , Método Simple Ciego , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/mortalidad , Tiempo de Tratamiento
12.
J Stroke Cerebrovasc Dis ; 30(11): 106064, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34464924

RESUMEN

Delayed cerebral ischemia (DCI) is the most feared complication of aneurysmal subarachnoid hemorrhage (aSAH). It increases the mortality and morbidity associated with aSAH. Previously, large cerebral artery vasospasm was thought to be the sole major contributing factor associated with increased risk of DCI. Recent literature has challenged this concept. We conducted a literature search using PUBMED as the prime source of articles discussing various other factors which may contribute to the development of DCI both in the presence or absence of large cerebral artery vasospasm. These factors include microvascular spasm, micro-thrombosis, cerebrovascular dysregulation, and cortical spreading depolarization. These factors collectively result in inflammation of brain parenchyma, which is thought to precipitate early brain injury and DCI. We conclude that diagnostic modalities need to be refined in order to diagnose DCI more efficiently in its early phase, and newer interventions need to be developed to prevent and treat this condition. These newer interventions are currently being studied in experimental models. However, their effectiveness on patients with aSAH is yet to be determined.


Asunto(s)
Isquemia Encefálica , Hemorragia Subaracnoidea , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiología , Isquemia Encefálica/prevención & control , Humanos , Hemorragia Subaracnoidea/complicaciones
13.
Folia Primatol (Basel) ; 92(4): 211-226, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34727553

RESUMEN

Optimal diet and functional response models are used to understand the evolution of primate foraging strategies. The predictions of these models can be tested by examining the geographic and seasonal variation in dietary diversity. Dietary diversity is a useful tool that allows dietary comparisons across differing sampling locations and time periods. Bonobos (Pan paniscus) are considered primarily frugivorous and consume fruits, leaves, insects, vertebrates, terrestrial herbaceous vegetation, and flowers. Frugivores, like bonobos, are valuable for examining dietary diversity and testing foraging models because they eat a variety of species and are subject to seasonal shifts in fruit availability. Frugivorous primate species thus allow for tests of how variation in dietary diversity is correlated with variation in ecological factors. We investigated measures of dietary diversity in bonobos at two research camps across field seasons within the same protected area (N'dele and Iyema) in Lomako Forest, Democratic Republic of the Congo. We compared the results of behavioral observation (1984/1985, 1991, 1995, 2014, and 2017) and fecal washing analysis (2007 and 2009) between seasons and study period using three diversity indices (Shannon's, Simpson's, and SW evenness). The average yearly dietary diversity indices at N'dele were Shannon's H' = 2.04, Simpson's D = 0.82, and SW evenness = 0.88 while at Iyema, the indices were Shannon's H' = 2.02, Simpson's D = 0.82, and SW evenness = 0.88. Behavioral observation data sets yielded significantly higher dietary diversity indices than fecal washing data sets. We found that food item (fruit, leaf, and flower) consumption was not associated with seasonal food availability for the 2017 behavioral observation data set. Shannon's index was lower during periods when fewer bonobo dietary items were available to consume and higher when fruit was abundant. Finally, we found that optimal diet models best-explained patterns of seasonal food availability and dietary diversity. Dietary diversity is an essential factor to consider when understanding primate diets and can be a tool in understanding variation in primate diets, particularly among frugivores. Dietary diversity varies across populations of the same species and across time, and it is critical in establishing a complete understanding of how primate diets change over time.


Asunto(s)
Conducta Alimentaria , Pan paniscus , Animales , Dieta/veterinaria , Bosques , Frutas
14.
Biol Blood Marrow Transplant ; 26(10): 1900-1905, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32640311

RESUMEN

Various reduced-intensity conditioning regimens are in use for allogeneic hematopoietic cell transplant (HSCT) in patients with idiopathic severe aplastic anemia (SAA). We describe the use of fludarabine, Campath, and low-dose cyclophosphamide (FCClow) conditioning in 15 children undergoing related or unrelated donor transplants. Total body irradiation (TBI) of 2 Gy was added for unrelated donor HSCT. At a median follow-up of 2.3 years, the failure-free survival was 100%, with low rates of infection and toxicity. There was no occurrence of grade III to IV acute graft-versus-host disease (GVHD). All patients had full donor myeloid chimerism post-HSCT, even with mixed chimerism in the T cell lineage. The absence of chronic GVHD and long-term stable mixed donor T cell chimerism confirms immune tolerance following FCClow (± TBI) conditioned transplantation in children with SAA.


Asunto(s)
Anemia Aplásica , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Alemtuzumab , Anemia Aplásica/terapia , Niño , Ciclofosfamida/uso terapéutico , Humanos , Acondicionamiento Pretrasplante , Vidarabina/análogos & derivados , Irradiación Corporal Total
15.
J Anim Ecol ; 89(6): 1511-1519, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32145069

RESUMEN

While the functional response of predators is commonly measured, recent work has revealed that the age and sex composition of prey killed is often a better predictor of prey population dynamics because the reproductive value of adult females is usually higher than that of males or juveniles. Climate is often an important mediating factor in determining the composition of predator kills, but we currently lack a mechanistic understanding of how the multiple facets of climate interact with prey abundance and demography to influence the composition of predator kills. Over 20 winters, we monitored 17 wolf packs in Yellowstone National Park and recorded the sex, age and nutritional condition of kills of their dominant prey-elk-in both early and late winter periods when elk are in relatively good and relatively poor condition, respectively. Nutritional condition (as indicated by per cent marrow fat) of wolf-killed elk varied markedly with summer plant productivity, snow water equivalent (SWE) and winter period. Moreover, marrow was poorer for wolf-killed bulls and especially for calves than it was for cows. Wolf prey composition was influenced by a complex set of climatic and endogenous variables. In early winter, poor plant growth in either year t or t - 1, or relatively low elk abundance, increased the odds of wolves killing bulls relative to cows. Calves were most likely to get killed when elk abundance was high and when the forage productivity they experienced in utero was poor. In late winter, low SWE and a relatively large elk population increased the odds of wolves killing calves relative to cows, whereas low SWE and poor vegetation productivity 1 year prior together increased the likelihood of wolves killing a bull instead of a cow. Since climate has a strong influence on whether wolves prey on cows (who, depending on their age, are the key reproductive components of the population) or lower reproductive value of calves and bulls, our results suggest that climate can drive wolf predation to be more or less additive from year to year.


Asunto(s)
Ciervos , Lobos , Animales , Bovinos , Femenino , Masculino , Parques Recreativos , Dinámica Poblacional , Conducta Predatoria
16.
J Anim Ecol ; 89(1): 120-131, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-30838656

RESUMEN

The extent to which prey space use actively minimizes predation risk continues to ignite controversy. Methodological reasons that have hindered consensus include inconsistent measurements of predation risk, biased spatiotemporal scales at which responses are measured and lack of robust null expectations. We addressed all three challenges in a comprehensive analysis of the spatiotemporal responses of adult female elk (Cervus elaphus) to the risk of predation by wolves (Canis lupus) during winter in northern Yellowstone, USA. We quantified spatial overlap between the winter home ranges of GPS-collared elk and three measures of predation risk: the intensity of wolf space use, the distribution of wolf-killed elk and vegetation openness. We also assessed whether elk varied their use of areas characterized by more or less predation risk across hours of the day, and estimated encounter rates between simultaneous elk and wolf pack trajectories. We determined whether observed values were significantly lower than expected if elk movements were random with reference to predation risk using a null model approach. Although a small proportion of elk did show a tendency to minimize use of open vegetation at specific times of the day, overall we highlight a notable absence of spatiotemporal response by female elk to the risk of predation posed by wolves in northern Yellowstone. Our results suggest that predator-prey interactions may not always result in strong spatiotemporal patterns of avoidance.


Asunto(s)
Ciervos , Lobos , Animales , Femenino , Movimiento , Conducta Predatoria , Estaciones del Año
17.
Eur J Nutr ; 59(8): 3723-3734, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32067098

RESUMEN

OBJECTIVE: Peripheral endothelial dysfunction (PED) is associated with major adverse cardiovascular events. Similar to cardio-protective Mediterranean diet, Chardonnay seeds are rich in polyphenols, fibers, and grape seed oil. In this randomized double-blinded trial, we investigated safety and incremental benefit of Chardonnay seed polyphenols-rich (PR), compared to polyphenols-free (PF), supplements on PED. METHODS: 89 patients with PED [reactive hyperemia-peripheral arterial tonometry (RH-PAT) index ≤ 2) were randomized 1:1 to 4.8 g (6 capsules)/day PR or PF for 4 months. PR and PF capsules had equal amounts of seed oil (~ 7% capsule weight), fibers, and carbohydrates, but only PR capsules contained polyphenols (~ 11% capsule weight). Baseline and follow-up RH-PAT indices (primary endpoint) and endothelial progenitor cells (EPC) levels were measured. Patients were asked to maintain their regular diet and exercise habits during study period. RESULTS: Baseline RH-PAT indices, demographics, lab values, and EPC levels were similar between groups. No significant adverse reactions to PR or PF were reported. Follow-up RH-PAT indices significantly increased (p < 0.05 vs. baseline) in both groups to similar extent (31 ± 39% PR vs. 49 ± 53% PF, p = 0.09). Circulating CD34 + EPCs equally increased (median + 55% vs. + 54%, p = 0.94) in PR and PF groups, respectively. CONCLUSION: PR and PF Chardonnay seed supplements were safe and improved peripheral endothelial function to similar extent in PED patients. However, there were no incremental benefits of PR over PF on RH-PAT indices or CD34 + EPC levels. Chardonnay seed supplements role in primary prevention of atherosclerosis, as add-on to healthy lifestyle and guidelines directed medical therapy, should be further explored. CLINICALTRIALS. GOV IDENTIFIER (NCT NUMBER): NCT02093455.


Asunto(s)
Aterosclerosis , Hiperemia , Arterias , Endotelio Vascular , Humanos , Polifenoles
18.
Neurocrit Care ; 33(2): 389-398, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32524527

RESUMEN

BACKGROUND: Early systolic blood pressure (SBP) reduction is believed to improve outcome after spontaneous intracerebral hemorrhage (ICH), but there has been a limited assessment of SBP trajectories in individual patients. We aimed to determine the prognostic significance of SBP trajectories in ICH. METHODS: We collected routine data on spontaneous ICH patients from two healthcare systems over 10 years. Unsupervised functional principal components analysis (FPCA) was used to characterize SBP trajectories over first 24 h and their relationship to the primary outcome of unfavorable shift on modified Rankin scale (mRS) at hospital discharge, categorized as an ordinal trichotomous variable (mRS 0-2, 3-4, and 5-6 defined as good, poor, and severe, respectively). Ordinal logistic regression models adjusted for baseline SBP and ICH volume were used to determine the prognostic significance of SBP trajectories. RESULTS: The 757 patients included in the study were 65 ± 23 years old, 56% were men, with a median (IQR) Glasgow come scale of 14 (8). FPCA revealed that mean SBP over 24 h and SBP reduction within the first 6 h accounted for 76.8% of the variation in SBP trajectories. An increase in SBP reduction (per 10 mmHg) was significantly associated with unfavorable outcomes defined as mRS > 2 (adjusted-OR = 1.134; 95% CI 1.044-1.233, P = 0.003). Compared with SBP reduction < 20 mmHg, worse outcomes were observed for SBP reduction = 40-60 mmHg (adjusted-OR = 1.940, 95% CI 1.129-3.353, P = 0.017) and > 60 mmHg, (adjusted-OR = 1.965, 95% CI 1.011, 3.846, P = 0.047). Furthermore, the association of SBP reduction and outcome varied according to initial hematoma volume. Smaller SBP reduction was associated with good outcome (mRS 0-2) in small (< 7.42 mL) and medium-size (≥ 7.42 and < 30.47 mL) hematomas. Furthermore, while the likelihood of good outcome was low in those with large hematomas (≥ 30.47 mL), smaller SBP reduction was associated with decreasing probability of severe outcome (mRS 5-6). CONCLUSION: Our analyses suggest that in the first 6 h SBP reduction is significantly associated with the in-hospital outcome that varies with initial hematoma volume, and early SBP reduction > 40 mmHg may be harmful in ICH patients. For early SBP reduction to have an effective therapeutic effect, both target levels and optimum SBP reduction goals vis-à-vis hematoma volume should be considered.


Asunto(s)
Antihipertensivos , Hipotensión , Antihipertensivos/farmacología , Presión Sanguínea , Hemorragia Cerebral/tratamiento farmacológico , Hospitales , Humanos , Hipotensión/tratamiento farmacológico , Masculino , Resultado del Tratamiento
19.
Aesthetic Plast Surg ; 44(4): 1364-1374, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32844270

RESUMEN

Is aesthetic surgery a business guided by market structures aimed primarily at material gain and profit or a surgical intervention intended to benefit patients and an integral part of the health-care system? Is it a frivolous subspecialty or does it provide a real and much needed service to a wide range of patients? At present, cosmetic surgery is passing through an identity crisis as well as an acute ethical dilemma. A closer look from an ethical viewpoint makes clear that the doctor who offers aesthetic interventions faces many serious ethical problems which have to do with the identity of the surgeon as a healer. Aesthetic surgery that works only according to market categories runs the risk of losing the view for the real need of patients and will be nothing else than a part of a beauty industry which has the only aim to sell something, not to help people. Such an aesthetic surgery is losing sight of real values and makes profit from the ideology of a society that serves only vanity, youthfulness, and personal success. Unfortunately, some colleagues brag that they chose the plastic surgery specialty just to become rich aesthetic surgeons, using marketing tactics to promote their practice. This is, at present, the image we project. As rightly proposed, going back a little to Hippocrates, to the basics of being a physician, is urgently warranted! Being a physician is all that a ''cosmetic'' surgeon should be. In the long run, how one skillfully and ethically practices the art of plastic surgery will always speak louder than any words.


Asunto(s)
Procedimientos de Cirugía Plástica , Cirugía Plástica , Belleza , Estética , Ética Médica , Humanos
20.
J Stroke Cerebrovasc Dis ; 29(12): 105340, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33017754

RESUMEN

Spontaneous primary intracerebral hemorrhage (ICH) is a stroke subtype associated with the highest mortality rate. High blood pressure (BP) is the most common cause of non-lobar ICH. Recent clinical trials have been inconclusive regarding the efficacy of aggressive BP lowering to improve ICH outcome. The association between high BP and ICH prognosis is rather complex and parameters other than absolute BP levels may be involved. In this regard, there is accruing evidence that BP variability (BPV) plays a major role in ICH outcome. Different BPV indices have been used to predict hematoma growth, neurological deterioration, and functional recovery. This review highlights the available evidence about the relationship between BPV and clinical outcomes among patients. We identified standard deviation (SD), residual SD, coefficient of variation, mean absolute change, average real variability, successive variation, spectral analysis using Fourier analysis, and functional successive variation (FSV) as indices to assess BPV. Most studies have demonstrated the association of BPV with ICH outcome, suggesting a need to monitor and control BP fluctuations in the routine clinical care of ICH patients. When large inter-subject variability exists, FSV is a viable alternative quantification of BPV as its computation is less sensitive to differences in the patient-specific observation schedules for BP than that of traditional indices.


Asunto(s)
Presión Sanguínea , Hemorragia Cerebral/etiología , Hematoma/etiología , Hipertensión/complicaciones , Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Determinación de la Presión Sanguínea , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/fisiopatología , Hemorragia Cerebral/terapia , Evaluación de la Discapacidad , Hematoma/diagnóstico , Hematoma/fisiopatología , Hematoma/terapia , Humanos , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Hipertensión/fisiopatología , Recuperación de la Función , Factores de Riesgo , Resultado del Tratamiento
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