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1.
Physiol Genomics ; 56(8): 519-530, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38808773

RESUMEN

Commercial culture of channel catfish (Ictalurus punctatus) occurs in earthen ponds that are characterized by diel swings in dissolved oxygen concentration that can fall to severe levels of hypoxia, which can suppress appetite and lead to suboptimal growth. Given the significance of the hypothalamus in regulating these processes in other fishes, an investigation into the hypothalamus transcriptome was conducted to identify specific genes and expression patterns responding to hypoxia. Channel catfish in normoxic water were compared with catfish subjected to 12 h of hypoxia (20% oxygen saturation; 1.8 mg O2/L; 27°C) followed by 12 h of recovery in normoxia to mimic 24 h in a catfish aquaculture pond. Fish were sampled at 0-, 6-, 12-, 18-, and 24-h timepoints, with the 6- and 12-h samplings occurring during hypoxia. A total of 190 genes were differentially expressed during the experiment, with most occurring during hypoxia and returning to baseline values within 6 h of normoxia. Differentially expressed genes were sorted by function into Gene Ontology biological processes and revealed that most were categorized as "response to hypoxia," "sprouting angiogenesis," and "cellular response to xenobiotic stimulus." The patterns of gene expression reported here suggest that transcriptome responses to hypoxia are broad and quickly reversibly with the onset of normoxia. Although no genes commonly reported to modulate appetite were found to be differentially expressed in this experiment, several candidates were identified for future studies investigating the interplay between hypoxia and appetite in channel catfish, including adm, igfbp1a, igfbp7, and stc2b.NEW & NOTEWORTHY Channel catfish are an economically important species that experience diel episodic periods of hypoxia that can reduce appetite. This is the first study to investigate their transcriptome from the hypothalamus in a simulated 24-h span in a commercial catfish pond, with 12 h of hypoxia and 12 h of normoxia. The research revealed functional groups of genes relating to hypoxia, angiogenesis, and glycolysis as well as individual target genes possibly involved in appetite regulation.


Asunto(s)
Hipotálamo , Hipoxia , Ictaluridae , Transcriptoma , Animales , Ictaluridae/genética , Transcriptoma/genética , Hipotálamo/metabolismo , Hipoxia/genética , Hipoxia/metabolismo , Estanques , Oxígeno/metabolismo , Acuicultura/métodos , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Perfilación de la Expresión Génica/métodos , Ontología de Genes
2.
J Vasc Surg ; 77(1): 122-128, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35842202

RESUMEN

OBJECTIVE: We have reported the 5-year results of a pivotal prospective, multicenter study conducted in the United States of a specifically designed iliac branch endoprosthesis (IBE; W.L. Gore & Associates, Flagstaff, AZ) for endovascular repair of aortoiliac aneurysms and common iliac artery aneurysms. METHODS: A total of 63 patients (98.4% male; mean age, 70 years) with aortoiliac or common iliac artery aneurysms had undergone implantation of a single IBE device and a bifurcated aortoiliac stent graft. Patients with bilateral common iliac artery aneurysms (n = 22; 34.9%) had undergone either staged occlusion or surgical revascularization of the contralateral internal iliac artery before study enrollment. At 5 years, 36 of the 63 patients had completed the final study follow-up examinations, including clinical examinations (n = 35) and computed tomography (n = 32), with the results evaluated by an independent core laboratory and adverse events adjudicated by a clinical events committee. RESULTS: At 5 years, freedom from all-cause mortality was 85.7% and freedom from aneurysm-related mortality was 100%. The nine deaths that had occurred (range, 132-1898 days) were adjudicated as unrelated to the aneurysm or procedure. Primary patency of the internal and external iliac artery IBE limbs was 95.1% and 100%, respectively. No patients had experienced new-onset buttock claudication on the IBE side or self-reported new-onset erectile dysfunction. The common iliac artery diameter on the IBE side was either unchanged or had decreased by ≥5 mm in 30 of the 31 patients (96.8%) with a baseline (1 month) and 5-year (range, 1641-2006 days) computed tomography scan available. Of the 31 evaluable patients, 9 (29.0%) had had an increase of ≥5 mm in the aortic diameter, 5 of whom had had a concurrent type II endoleak. No type I or type III endoleaks or device migration were identified by the core laboratory. Six patients had undergone eight secondary interventions, including five interventions for a type II endoleak. The freedom from secondary intervention was 90.5%. CONCLUSIONS: The 5-year results of our prospective, multicenter study have confirmed the safety, efficacy, and durability of the IBE device for the treatment of aortoiliac and iliac artery aneurysms. The device effectively prevented common iliac artery aneurysm rupture, maintained the patency of the internal iliac artery, and avoided the complications associated with internal iliac artery sacrifice. Although common iliac artery aneurysm enlargement was rare, abdominal aortic enlargement was more common, suggesting that the outcomes of endovascular aneurysm repair might be different for patients with or without associated common iliac artery aneurysms.


Asunto(s)
Aneurisma de la Aorta Abdominal , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Aneurisma Ilíaco , Humanos , Masculino , Anciano , Femenino , Prótesis Vascular/efectos adversos , Arteria Ilíaca/cirugía , Endofuga/etiología , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/complicaciones , Estudios Prospectivos , Resultado del Tratamiento , Aneurisma Ilíaco/diagnóstico por imagen , Aneurisma Ilíaco/cirugía , Stents/efectos adversos , Diseño de Prótesis
3.
Proc Natl Acad Sci U S A ; 117(8): 3989-3995, 2020 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-32047035

RESUMEN

Natural gas is a key energy resource, and understanding how it forms is important for predicting where it forms in economically important volumes. However, the origin of dry thermogenic natural gas is one of the most controversial topics in petroleum geochemistry, with several differing hypotheses proposed, including kinetic processes (such as thermal cleavage, phase partitioning during migration, and demethylation of aromatic rings) and equilibrium processes (such as transition metal catalysis). The dominant paradigm is that it is a product of kinetically controlled cracking of long-chain hydrocarbons. Here we show that C2+n-alkane gases (ethane, propane, butane, and pentane) are initially produced by irreversible cracking chemistry, but, as thermal maturity increases, the isotopic distribution of these species approaches thermodynamic equilibrium, either at the conditions of gas formation or during reservoir storage, becoming indistinguishable from equilibrium in the most thermally mature gases. We also find that the pair of CO2 and C1 (methane) exhibit a separate pattern of mutual isotopic equilibrium (generally at reservoir conditions), suggesting that they form a second, quasi-equilibrated population, separate from the C2 to C5 compounds. This conclusion implies that new approaches should be taken to predicting the compositions of natural gases as functions of time, temperature, and source substrate. Additionally, an isotopically equilibrated state can serve as a reference frame for recognizing many secondary processes that may modify natural gases after their formation, such as biodegradation.

4.
Artículo en Inglés | MEDLINE | ID: mdl-37249490

RESUMEN

ABSTRACT: The Milwaukee County Medical Examiner's Office performed an evidence-based review of natural deaths certified without autopsy or toxicology testing. Three hundred fifteen such cases from 2020 and 2021 were selected. This study reviewed the deaths to determine if the cause was drug-related instead due to natural disease.Blood samples were screened by liquid chromatography-quadrupole mass spectrometry with time-of-flight detector. The analytes detected were evaluated for contribution to the cause resulting in a change in manner from natural to accident or suicide. Confirmatory analysis was performed where appropriate, and results were reported to the forensic pathologist for evaluation. Where appropriate, the death certificate was amended.As a result of the screening and confirmatory work, 18 cases were identified where significant drugs were detected, and thus the cause and manner of death were amended. One case was amended from natural to suicide after a conversation with the family about the toxicology findings. The remaining cases were amended to a manner of accident. The scope of drugs responsible for the deaths included prescription and illicit.

5.
J Environ Manage ; 348: 119201, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37839200

RESUMEN

Sightseeing air tours have proven to be a challenging management issue for many tourist destinations around the world, especially at locations meant to protect natural and cultural resources and wilderness character. Two of the primary challenges with managing air tours are a lack of information about their travel patterns and how such patterns result in a measurable noise impact to listeners. Recent studies have highlighted the usefulness of newer technology for tracking aircraft travel patterns, particularly over national parks. In this synthesis, we pair aircraft tracks with acoustic data using a quantitative observer-based audibility modelling software toolkit. The findings delimit the long-term geographic scope of audibility for specific aircraft noise sources above landscapes of Hawai'i Volcanoes and Denali National Parks, U.S. and identify practical, 3-dimensional offset distances that can be used to reduce the functional effects of air tour noise in terms of sound level.


Asunto(s)
Ruido , Viaje , Aeronaves , Parques Recreativos , Vida Silvestre
6.
Opt Lett ; 47(1): 13-16, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34951870

RESUMEN

We demonstrate a multi-photon excitation (MPE) scheme for luminescence thermometry using ScVO4:Bi3+. MPE is performed using a 37 fs Ti:sapphire laser pulse centered at 800 nm. Log-log plots of the phosphorescence intensity versus excitation power show that the 800 nm MPE of ScVO4:Bi3+ involves a 2- and 3-photon absorption process in comparison with a single-photon excitation (SPE) process at 266 and 400 nm. Spectroscopic investigation shows that with the 800 nm MPE and 266 nm SPE schemes, the emission spectra of ScVO4:Bi3+ are similarly characterized by emissions of the VO4 3- groups and Bi3+. MPE is advantageous to suppress fluorescence that interferes with the phosphorescence signal. We demonstrate this aspect for a ScVO4:Bi3+ coating applied on an alumina substrate. The luminescence lifetime is calibrated with temperature in the range of 294-334 K; the MPE scheme has an equally impressive temperature sensitivity (3.4-1.7%/K) and precision (0.2-0.7 K) compared with the SPE schemes. The MPE scheme can be applied to a variety of phosphors and is valuable for precise temperature measurements, even in applications where isolating interfering background emissions is challenging.

7.
J Gen Intern Med ; 37(9): 2224-2229, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35710662

RESUMEN

INTRODUCTION: Clinical reasoning encompasses the process of data collection, synthesis, and interpretation to generate a working diagnosis and make management decisions. Situated cognition theory suggests that knowledge is relative to contextual factors, and clinical reasoning in urgent situations is framed by pressure of consequential, time-sensitive decision-making for diagnosis and management. These unique aspects of urgent clinical care may limit the effectiveness of traditional tools to assess, teach, and remediate clinical reasoning. METHODS: Using two validated frameworks, a multidisciplinary group of clinicians trained to remediate clinical reasoning and with experience in urgent clinical care encounters designed the novel Rapid Evaluation Assessment of Clinical Reasoning Tool (REACT). REACT is a behaviorally anchored assessment tool scoring five domains used to provide formative feedback to learners evaluating patients during urgent clinical situations. A pilot study was performed to assess fourth-year medical students during simulated urgent clinical scenarios. Learners were scored using REACT by a separate, multidisciplinary group of clinician educators with no additional training in the clinical reasoning process. REACT scores were analyzed for internal consistency across raters and observations. RESULTS: Overall internal consistency for the 41 patient simulations as measured by Cronbach's alpha was 0.86. A weighted kappa statistic was used to assess the overall score inter-rater reliability. Moderate reliability was observed at 0.56. DISCUSSION: To our knowledge, REACT is the first tool designed specifically for formative assessment of a learner's clinical reasoning performance during simulated urgent clinical situations. With evidence of reliability and content validity, this tool guides feedback to learners during high-risk urgent clinical scenarios, with the goal of reducing diagnostic and management errors to limit patient harm.


Asunto(s)
Razonamiento Clínico , Evaluación Educacional , Competencia Clínica , Humanos , Proyectos Piloto , Reproducibilidad de los Resultados
8.
Health Commun ; 37(4): 467-475, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33950764

RESUMEN

This study describes differences in medicolegal death investigators' written descriptions for people who died by homicide, suicide, or accident. We evaluated 17 years of death descriptions from a midsized metropolitan midwestern county in the United States to assess how death investigators psychologically respond to different manners of death (N = 10,408 cases). Automated text analyses suggest investigators describe accidental deaths with more immediacy relative to homicides, while they also described suicidal deaths in less emotional terms than homicides as well. These data suggest medicolegal death investigators have different psychological reactions to circumstances and manners of death as indicated by their professional writing. Future research may surface context-specific psychological reactions to vicarious trauma that could inform the design or personalization of workplace-coping interventions.


Asunto(s)
Ideación Suicida , Suicidio , Accidentes , Causas de Muerte , Homicidio , Humanos , Estudios Retrospectivos , Estados Unidos/epidemiología
9.
Aesthetic Plast Surg ; 46(3): 1287-1289, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34799762

RESUMEN

A non-aesthetic post-abdominoplasty umbilicus is known to be a significant concern for many patients who consider this procedure, due to its central and visible location. The goal of this method is to minimize the visible scar and create a natural-looking and aesthetically pleasing umbilicus. In this multimedia article, we illustrate our technique that is both reproducible and easy to perform. It produces a scarless caudal aspect, pleasant depth, and natural superior hooding appearance to the post-op umbilicus. Limitations of this technique are discussed.Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Abdominoplastia , Ombligo , Abdominoplastia/métodos , Cicatriz/prevención & control , Cicatriz/cirugía , Humanos , Ombligo/cirugía
10.
Aesthetic Plast Surg ; 46(2): 667-674, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34462800

RESUMEN

BACKGROUND: The purpose of this study was to determine the effectiveness of using ultrasonic assisted liposuction (UAL) to achieve sufficient breast symmetry allowing for the use of same sized implants in patients presenting for elective breast augmentation surgery. METHODS: A retrospective review was performed of patients presenting for augmentation mammoplasty with breast asymmetry who underwent ultrasonic assisted liposuction in combination with implant augmentation. Pre-operative differences in breast volumes were determined using water displacement, and these measurements were compared to final lipoaspirates required to achieve symmetry. To estimate the volume of lipoaspirate required, we suggested to aim for twice the volume difference obtained by water displacement. The success of the procedure was measured by the ability to use the same size implants bilaterally. RESULTS: A total of 35 patients were included in this review. In 85% of patients, UAL was sufficient to permit the use of equally sized implants bilaterally. However, when different sized implants were required, the size difference between implants was not greater than 25 cc. The UAL was also effective in correcting minor ptosis and nipple position. The main observed disadvantage was prolonged bruising and swelling. CONCLUSION: The use of UAL for correction of primary breast asymmetry with bilateral breast augmentation allows balancing of breast tissue volumes and the use of same size implants and eliminates the need for balancing mastopexy procedures. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Asunto(s)
Implantación de Mama , Implantes de Mama , Lipectomía , Mamoplastia , Implantación de Mama/métodos , Implantes de Mama/efectos adversos , Estética , Humanos , Mamoplastia/métodos , Pezones/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Ultrasonido , Agua
11.
J Vasc Surg ; 74(5): 1558-1564.e1, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34082005

RESUMEN

OBJECTIVE: The GORE EXCLUDER iliac branch endoprosthesis (IBE; W.L. Gore & Associates, Flagstaff, Ariz) is designed to preserve internal iliac artery (IIA) patency during endovascular treatment of aneurysms involving the common iliac artery. The device is intended to conform to iliac tortuosity, which may decrease adverse iliac events (AIE). The objective of this study was to evaluate risk factors for AIE after IBE implantation. METHODS: This was a post hoc analysis of the prospective, multicenter GORE 12-04 IBE pivotal trial. Patients with preoperative and postoperative axial imaging were included, with analysis based on each treated iliac system. An independent core laboratory performed all scan measurements, including iliac diameters, lengths, and tortuosity. Conformability was analyzed by the changes in tortuosity after IBE deployment, with less change indicating greater conformation. The end point was AIE, defined as ipsilateral radiographic or clinical complications. Critical nonconformation was defined as a threshold change in tortuosity associated with a significant increase in AIE. RESULTS: We included 98 patients with 101 treated iliac systems. There were eight AIE (8%; six IIA component occlusions, one iliac branch component occlusion, and one EIA dissection requiring reintervention). Patients with AIE had smaller IIA diameters and less IBE conformability. After multivariable logistic regression analysis, an IIA diameter of less than 10 mm and a change in total iliac tortuosity beyond -15% were independently associated with AIE (odds ratio, 12 [interquartile range, 1.4-110] and odds ratio, 8.2 [interquartile range, 1.5-46], respectively), and the latter was used to define critical nonconformation. Critical nonconformation occurred in 11% of treated systems, and was associated with a high rate of AIE (36% vs 4%; P = .004). CONCLUSIONS: Endograft conformation is a novel device property and technical outcome that, along with a larger IIA diameter, is associated with freedom from AIE after IBE deployment. An evaluation of these risk factors may better inform the management of patients with iliac aneurysmal disease. Further research on endograft conformation and patient outcomes is warranted, particularly for those with challenging anatomy undergoing complex procedures.


Asunto(s)
Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Aneurisma Ilíaco/cirugía , Arteria Ilíaca/cirugía , Anciano , Anciano de 80 o más Años , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Femenino , Humanos , Aneurisma Ilíaco/diagnóstico por imagen , Aneurisma Ilíaco/fisiopatología , Arteria Ilíaca/diagnóstico por imagen , Arteria Ilíaca/fisiopatología , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos , Grado de Desobstrucción Vascular
12.
Ann Vasc Surg ; 71: 40-47, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32889165

RESUMEN

BACKGROUND: Aneurysm sac remodeling is a complex multifactorial process with unknown factors influencing sac regression after endovascular aortic aneurysm repair (EVAR). We sought to identify factors associated with this process by analyzing data obtained from patients treated with the GORE EXCLUDER endovascular aneurysm repair (EVAR) endoprosthesis from December 2010 to October 2016 enrolled in the Global Registry for Endovascular Aortic Treatment (GREAT). METHODS: All patients enrolled in GREAT with three years CT angiography (CTA) follow-up in each of the three successive years after EVAR were included. The percentage of sac size reduction toward device diameter was calculated and used as a surrogate for sac regression with the formula used being: sac size reduction = ((AAA baseline diameter - AAA diameter at follow-up)/(AAA baseline diameter - device diameter))∗100. The cohort was divided into two groups in accordance with the percentage of aneurysm sac reduction at three years; one with the top quartile of patients and the other with the lowest three quartiles. Demographic and procedural variables were analyzed using univariate and regression modeling to determine factors predictive of sac regression. RESULTS: There were 3265 subjects enrolled with follow-up as of May 2018 of which 526 (16.2%) had three years of CTA surveillance. Overall aneurysm sac size decreased from a mean of 58.0 mm (Std Dev: 10.4, range: 34.2, 100.0) to a mean of 49.3 mm (Std Dev: 14.1, range: 0, 140) for a percentage reduction toward device diameter of a mean 28.2% (Std Dev: 39.0, range: -103.7, 183.9). On multivariate logistic regression model; two factors proved to be statistically significant contributors to a larger percentage reduction in aneurysm sac: a conical neck (odds ratio [OR] = 1.64, P-value = 0.023) and a larger proximal device diameter (OR = 1.09, P-value = 0.023). On the other hand, two factors were negative predictors of sac shrinkage, namely: old age (OR = 0.96, P-value = 0.002) and larger baseline aneurysm sac diameter (OR = 0.98, P-value = 0.028). CONCLUSIONS: Aneurysms with conical necks and larger proximal device neck diameters have an increased percentage change in sac size over time after EVAR. Older age and larger initial diameters of aneurysms were negatively associated with percentage change in sac size as well as sac regression. Further study is needed to determine the clinical utility of these observations and applicability across multiple endoprosthesis platforms.


Asunto(s)
Aneurisma de la Aorta/cirugía , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Remodelación Vascular , Factores de Edad , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/fisiopatología , Aortografía , Australia , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Brasil , Angiografía por Tomografía Computarizada , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda , Diseño de Prótesis , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
13.
Opt Lett ; 45(17): 4758-4761, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32870850

RESUMEN

We employ dual-probe one-dimensional (1D) femtosecond (fs)/picosecond (ps) hybrid rotational coherent anti-Stokes Raman spectroscopy (HRCARS) to investigate simultaneous temperature, pressure, and O2/N2 measurements for gas-phase diagnostics. The dual-probe HRCARS technique allows for simultaneous measurements from the time and frequency-domain. A novel approach for measuring pressure, which offers high accuracy (<1%) and precision (0.42%), is presented. The technique is first demonstrated in a chamber for a range of pressures (1-1.5 bar). This technique shows an impressive capability of resolving 1D pressure gradients arising from a N2 jet impinging on a surface, both in laminar and turbulent conditions. The technique is shown to be capable of resolving single-shot pressure gradients (0.04 bar/mm) originating from kinetic energy conversion to pressure and resolves characteristic O2/N2 structures from laminar and turbulent mixing.

14.
Environ Manage ; 66(2): 263-277, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32564214

RESUMEN

Parks and protected areas are complex, and managers often need integrated social-ecological science-based information that illuminates the dynamic interactions between the biophysical and social processes. However, modeling and determining social-ecological connections are difficult due to disciplinary paradigms, divergent research questions, and data sets representing different scales. During this investigation, researchers sought to evaluate social-ecological linkages at a large salt pan (Bonneville Salt Flats) in western Utah (US). Specifically, the investigation evaluated how the changing level and location of salt-crust moisture and ponding water influenced visitors' spatial distribution of use and important elements of their experience. The findings indicate that visitors travel more distance, spend more time recreating, and use the Salt Flats in higher densities during dry conditions. However, the results also highlight that importance levels ascribed to specific aspects of the visitor experience remained relatively stable regardless of changes in salt-crust moisture and ponding water. Illuminating such linkages is important because most natural resource issues in society, including resources at the Bonneville Salt Flats, are not solely ecological or social in nature but characterized by deeper enmeshment between the two.


Asunto(s)
Conservación de los Recursos Naturales , Recreación , Cloruro de Sodio , Viaje , Utah
15.
J Am Chem Soc ; 141(40): 15910-15920, 2019 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-31508944

RESUMEN

A new catalytically active zeolite, designated EMM-17 (ExxonMobil Material-17), with a three-dimensional (3D) 11 × 10 × 10-ring topology has been discovered from high throughput experiments while evaluating a family of new organic structure directing agents (OSDAs), 1-alkyl-4-(pyrrolidin-1-yl)pyridin-1-ium hydroxide. The framework structure was determined by model building techniques and confirmed by diffraction calculations. The EMM-17 structure is a random intergrowth of two polymorphs which have a 3D arrangement of intersecting 11 × 10 × 10-ring pores. EMM-17 is stable to calcination to remove the OSDA and can be reproducibly synthesized in the presence of fluoride using common, inexpensive reagents over a wide Si/Al range from 15 to infinity, enabling the catalyst acidity to be tailored to almost any petrochemical application. Unlike OSDAs for many new zeolite structures, the OSDAs for EMM-17 are prepared in one simple alkylation step, making EMM-17 an easy to prepare, highly accessible, catalytically active zeolite. Zeolites containing odd numbered channel sizes are rare, and this is the first confirmed example of a 3D 11-ring aluminosilicate zeolite with a pore size in between those of the commercially important 10- and 12-ring zeolites such as ZSM-5 and Zeolite-Y, respectively. Catalysts prepared from EMM-17 exhibit significantly higher activity for catalytic isomerization with no loss in selectivity than current state of the art catalysts. Catalytic isomerization of linear to branched alkanes is a critical component of commercial dewaxing, allowing for the improvement of cold flow properties of hydrocarbon fuels and lubricants through selective hydroisomerization of normal paraffins.

16.
Artículo en Inglés | MEDLINE | ID: mdl-30743059

RESUMEN

Cortisol is a glucocorticoid hormone which is an endocrine signaling molecule in all vertebrates and acts through intracellular glucocorticoid receptors (GRs). Cortisol affects many biological functions including immunity, stress, growth, and reproduction. The objective of this study was to investigate the ontogeny of the cortisol and GR stress response in channel catfish (Ictalurus punctatus) at several early life stages. To accomplish this, resting and stress-induced levels of tissue cortisol and the two catfish GRs (GR-1 and GR-2) expression were measured. Resting cortisol levels in newly fertilized eggs averaged 2.4 ±â€¯0.2 ng/egg and decreased to 0.4 ±â€¯0.01 ng/egg by day 5. Cortisol levels in newly fertilized eggs subjected to an acute stress (lowered dissolved oxygen from 6.5 mg/L to 1.8 mg/L) averaged 2.3 ±â€¯0.1 ng/egg and decreased to 0.3 ±â€¯0.03 ng/egg by day 5. At hatching, resting cortisol levels were 24 ±â€¯1.0 ng/0.1 g tissue while levels increased to 83 ±â€¯2.0 ng/0.1 g tissue in fry subjected to an acute stress (P < .05). Four days post-hatch, resting cortisol levels were 83 ±â€¯1.0 ng/0.1 g tissue while levels increased to 149 ±â€¯4.0 ng/0.1 g tissue in fry subjected to an acute stress (P < .01). There was no significant difference between GR-1 and GR-2 mRNA in stressed and unstressed newly hatched fry. Four days post-hatch, GR-1 mRNA increased 3-fold while GR-2 mRNA increased 2-fold in fry that were subjected to low dissolved oxygen conditions (P < .05). These results indicate that cortisol biosynthesis, integration and maturation of the hypothalamic-pituitary-interrenal (HPI) axis can be observed in channel catfish at hatching. The upregulation of GR-1 and -2 mRNA in stressed fry supports roles for both transcripts in integrating the channel catfish stress response.


Asunto(s)
Proteínas de Peces/fisiología , Hidrocortisona/fisiología , Ictaluridae/fisiología , Receptores de Glucocorticoides/fisiología , Estrés Fisiológico , Animales , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Hidrocortisona/biosíntesis , Ictaluridae/crecimiento & desarrollo , ARN Mensajero/genética , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo
17.
J Am Chem Soc ; 140(6): 2076-2079, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29385348

RESUMEN

Control of polymer initiation, propagation and termination is important in the development of complex polymer structures and advanced materials. Typically, this has been achieved chemically, electrochemically, photochemically or mechanochemically. Electrochemical control has been demonstrated in radical polymerizations; however, regulation of a cationic polymerization has yet to be achieved. Through the reversible oxidation of a polymer chain end with an electrochemical mediator, temporal control over polymer chain growth in cationic polymerizations was realized. By subjecting a stable organic nitroxyl radical mediator and chain transfer agent to an oxidizing current, control over polymer molecular weight and dispersity is demonstrated and excellent chain end fidelity allows for the synthesis of block copolymers.

19.
Dis Aquat Organ ; 129(2): 99-106, 2018 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-29972370

RESUMEN

We investigated the effects of a phytogenic feed additive on disease susceptibility to Edwardsiella ictaluri in channel catfish Ictalurus punctatus and regulation of 6 rhamnose-binding lectin (RBL) genes. Juvenile catfish (n = 250, 13.4 ± 0.1 g) were allotted to the following treatments: control (floating diet) or EO (floating diet supplemented with essential oils; Digestarom® P.E.P. MGE). The fish were fed their respective diets for 6 wk. Following subjection to different feed treatments, all fish were exposed to pathogenic E. ictaluri by bath immersion. Another group of fish were not challenged (non-challenged controls, fed control feed). Mucosal tissue samples were taken to quantify gene expression levels of RBL on Days 1 and 2 post-challenge. After challenge, survival was higher (64.4 vs. 48.0%) in fish fed EO compared to controls (p < 0.05). Relative to non-challenged controls, gill RBL1a mRNA was higher in fish fed EO (p < 0.05) on Day 1 while gill RBL3b was higher in fish fed EO (p < 0.01) on Days 1 and 2, respectively. RBL5a in the skin and proximate small intestine did not change significantly relative to non-challenged fish on Days 1 and 2 of the disease challenge. Results demonstrate that Digestarom® P.E.P. MGE improved survival of channel catfish challenged with E. ictaluri. One of the mechanisms through which essential oils may improve survival is through upregulation of RBL1a and RBL3b in the gill.


Asunto(s)
Alimentación Animal/análisis , Bagres/metabolismo , Edwardsiella ictaluri/fisiología , Infecciones por Enterobacteriaceae/veterinaria , Enfermedades de los Peces/prevención & control , Proteínas de Peces/metabolismo , Lectinas/metabolismo , Animales , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/prevención & control , Aditivos Alimentarios , Regulación de la Expresión Génica , ARN Mensajero/genética , ARN Mensajero/metabolismo
20.
J Vasc Surg ; 66(3): 775-785, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28559174

RESUMEN

OBJECTIVE: The GORE EXCLUDER Iliac Branch Endoprosthesis (IBE; W. L. Gore and Associates, Flagstaff, Ariz) is an iliac branch stent graft system designed to preserve internal iliac artery perfusion during endovascular repair of aortoiliac aneurysms (AIAs) and common iliac artery (CIA) aneurysms (CIAAs). We report the 6-month primary end point results of the IBE 12-04 United States pivotal trial for endovascular treatment of AIAs and CIAAs using the IBE device. METHODS: The trial prospectively enrolled 63 patients with AIA or CIAA who underwent implantation of the IBE device at 28 centers in the United States from 2013 to 2015. All patients underwent placement of a single IBE device. Twenty-two patients (34.9%) with bilateral CIAs were enrolled after undergoing staged coil or plug embolization (21 of 22) or surgical revascularization (1 of 22) of the contralateral internal iliac artery. Follow-up at 30 days and 6 months included clinical assessment and computed tomography angiography evaluation as assessed by an independent core laboratory. The primary effectiveness end point was freedom from IBE limb occlusion and reintervention for type I or III endoleak and ≥60% stenosis at 6 months, and the secondary effectiveness end point was freedom from new onset of buttock claudication on the IBE side at 6 months. RESULTS: Mean CIA diameter on the IBE side was 41.0 ± 11.4 mm (range, 25.2-76.3 mm). There were no procedural deaths, and technical success, defined as successful deployment and patency of all IBE components and freedom from type I or III endoleak, was 95.2% (60 of 63). Data for 61 patients were available for primary and secondary effectiveness end point analysis. Internal iliac limb patency was 95.1% (58 of 61), and no new type I or III endoleaks or device migrations were observed at 6 months. The three patients with loss of internal iliac limb patency were asymptomatic, and freedom from new-onset buttock claudication on the IBE side was 100% at 6 months. New-onset buttock claudication occurred on the non-IBE treatment side in six of 21 patients (28.6%) who underwent staged internal iliac artery coil embolization. CONCLUSIONS: These results confirm that the IBE device is effective at treating CIAAs and AIAs, maintaining blood flow into the internal iliac artery, and avoiding complications associated with internal iliac artery sacrifice. Follow-up will be continued for 5 years to establish the long-term durability of iliac aneurysm repair with the IBE device.


Asunto(s)
Aneurisma de la Aorta/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Aneurisma Ilíaco/cirugía , Stents , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/fisiopatología , Aortografía/métodos , Implantación de Prótesis Vascular/efectos adversos , Angiografía por Tomografía Computarizada , Supervivencia sin Enfermedad , Procedimientos Endovasculares/efectos adversos , Femenino , Humanos , Aneurisma Ilíaco/diagnóstico por imagen , Aneurisma Ilíaco/fisiopatología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Diseño de Prótesis , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos , Grado de Desobstrucción Vascular
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