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1.
Angew Chem Int Ed Engl ; 63(33): e202408569, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-38837843

RESUMEN

The integration of hostless battery-like metal anodes for hybrid supercapacitors is a realistic design method for energy storage devices with promising future applications. With significant Cr element deposits on Earth, exceptionally high theoretical capacity (1546 mAh g-1), and accessible redox potential (-0.74 V vs. reversible hydrogen electrode) of Cr metals, the design of Cr anodes has rightly come into our focus. This work presents a breakthrough design of a flexible Cr-ion hybrid supercapacitor (CHSC) based on a porous graphitized carbon fabric (PGCF) substrate prepared by K2FeO4 activation. In the CHSC device, PGCF acts as both a current collector and cathode material due to its high specific surface area and superior conductivity. The use of a highly concentrated LiCl-CrCl3 electrolyte with high Cr plating/stripping efficiency and excellent antifreeze properties enables the entire PGCF-based CHSC to achieve well-balanced performance in terms of energy density (up to 1.47 mWh cm-2), power characteristics (reaching 9.95 mW cm-2) and durability (95.4 % capacity retention after 30,000 cycles), while realizing it to work well under harsh conditions of -40 °C. This work introduces a new concept for low-temperature energy storage technology and confirms the potential application of Cr anodes in hybrid supercapacitors.

2.
Nano Lett ; 22(16): 6760-6766, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35930625

RESUMEN

We report experimental investigations of transport through bilayer graphene (BLG)/chromium trihalide (CrX3; X = Cl, Br, I) van der Waals interfaces. In all cases, a large charge transfer from BLG to CrX3 takes place (reaching densities in excess of 1013 cm-2), and generates an electric field perpendicular to the interface that opens a band gap in BLG. We determine the gap from the activation energy of the conductivity and find excellent agreement with the latest theory accounting for the contribution of the σ bands to the BLG dielectric susceptibility. We further show that for BLG/CrCl3 and BLG/CrBr3 the band gap can be extracted from the gate voltage dependence of the low-temperature conductivity, and use this finding to refine the gap dependence on the magnetic field. Our results allow a quantitative comparison of the electronic properties of BLG with theoretical predictions and indicate that electrons occupying the CrX3 conduction band are correlated.

3.
Nano Lett ; 20(7): 5030-5035, 2020 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-32463247

RESUMEN

Exchange bias is a physical phenomenon whereby the spins of a ferromagnet are pinned by those of an antiferromagnet, and this phenomenon has played an undisputed role in magnetic data storage. Over the past few decades, this effect has been observed in a variety of antiferromagnet/ferromagnet systems. New aspects of this phenomenon are being discovered. With the increasing interest in van der Waals (vdW) magnets, we address the question whether the effect can exist in magnetic vdW heterostructures. Here, we report exchange-bias fields of over 50 mT in mechanically exfoliated CrCl3/Fe3GeTe2 heterostructures at 2.5 K, the value of which is highly tunable by the field-cooling process and the heterostructure thickness. We postulate an intuitive picture explaining how the effect arises in this vdW heterostructure, as well as explaining the practical difficulty associated with capturing the effect. This work opens up new routes toward designing spintronic devices made of atomically thin vdW magnets.

4.
Molecules ; 26(4)2021 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-33671782

RESUMEN

CrCl3(thf)3 is a common starting material in the synthesis of organometallic and coordination compounds of Cr. Deposited as an irregular solid with no possibility of recrystallization, it is not a purity guaranteed chemical, causing problems in some cases. In this work, we disclose a well-defined form of the THF adduct of CrCl3 ([CrCl2(µ-Cl)(thf)2]2), a crystalline solid, that enables structure determination by X-ray crystallography. The EA data and XRD pattern of the bulk agreed with the revealed structure. Moreover, its preparation procedure is facile: evacuation of CrCl3·6H2O at 100 °C, treatment with 6 equivalents of Me3SiCl in a minimal amount of THF, and crystallization from CH2Cl2. The ethylene tetramerization catalyst [iPrN{P(C6H4-p-Si(nBu)3)2}2CrCl2]+[B(C6F5)4]- prepared using well-defined [CrCl2(µ-Cl)(thf)2]2 as a starting material exhibited a reliably high activity (6600 kg/g-Cr/h; 1-octene selectivity at 40 °C, 75%), while that of the one prepared using the impure CrCl3(thf)3 was inconsistent and relatively low (~3000 kg/g-Cr/h). By using well-defined [CrCl2(µ-Cl)(thf)2]2 as a Cr source, single crystals of [(CH3CN)4CrCl2]+[B(C6F5)4]- and [{Et(Cl)Al(N(iPr)2)2}Cr(µ-Cl)]2 were obtained, allowing structure determination by X-ray crystallography, which had been unsuccessful when the previously known CrCl3(thf)3 was used as the Cr source.


Asunto(s)
Cromo/química , Complejos de Coordinación/química , Furanos/química , Complejos de Coordinación/síntesis química , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular
5.
BMC Nephrol ; 21(1): 108, 2020 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-32228497

RESUMEN

BACKGROUND: Prior papers have been inconsistent regarding how much creatinine clearance (CrCl) overestimates glomerular filtration rate (GFR). A recent cross-sectional study suggested that measurement error alone could entirely account for the longstanding observation that CrCl/GFR ratio is larger when GFR is lower among patients with chronic kidney disease (CKD); but there have been no validation of this in other cohorts. METHODS: To fill these gaps in knowledge regarding the relation between CrCl and GFR, we conducted cross-sectional and longitudinal analysis of the Modification of Diet in Renal Disease study (MDRD) and African American Study of Kidney Disease and Hypertension (AASK); and cross-sectional analysis of a clinical dataset from the Mayo Clinic of four different patient populations (CKD patients, kidney transplant recipients, post kidney donation subgroup and potential kidney donors). In the cross-sectional analyses (MDRD, AASK and Mayo Clinic cohort), we examined the relation between the CrCl/iothalamate GFR (iGFR) ratio at different categories of iGFR or different levels of CrCl. In the MDRD and AASK longitudinal analyses, we studied how the CrCl/iGFR ratio changed with those who had improvement in iGFR (CrCl) over time versus those who had worsening of iGFR (CrCl) over time. RESULTS: Observed CrCl/iGFR ratios were generally on the lower end of the range reported in the literature for CKD (median 1.24 in MDRD, 1.13 in AASK and 1.25 in Mayo Clinic cohort). Among CKD patients in whom CrCl and iGFR were measured using different timed urine collections, CrCl/iGFR ratio were higher with lower iGFR categories but lower with lower CrCl categories. However, among CKD patients in whom CrCl and iGFR were measured using the same timed urine collections (which reduces dis-concordant measurement error), CrCl/iGFR ratio were higher with both lower iGFR categories and lower CrCl categories. CONCLUSIONS: These data refute the recent suggestion that measurement error alone could entirely account for the longstanding observation that CrCl/GFR ratio increases as GFR decreases in CKD patients. They also highlight the lack of certainty in our knowledge with regard to how much CrCl actually overestimates GFR.


Asunto(s)
Creatinina , Tasa de Filtración Glomerular , Ácido Yotalámico/farmacología , Pruebas de Función Renal , Insuficiencia Renal Crónica , Sesgo , Medios de Contraste/farmacología , Creatinina/análisis , Creatinina/sangre , Estudios Transversales , Femenino , Humanos , Pruebas de Función Renal/métodos , Pruebas de Función Renal/normas , Túbulos Renales/fisiopatología , Masculino , Tasa de Depuración Metabólica/fisiología , Persona de Mediana Edad , Eliminación Renal/fisiología , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/etiología , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/cirugía , Estadística como Asunto/métodos , Estadística como Asunto/normas
7.
Biochem Biophys Res Commun ; 456(1): 513-8, 2015 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-25490390

RESUMEN

Dendritic cells (DCs) pulsed with exosomes can stimulate efficient cytotoxic T-lymphocyte responses and anti-tumor immunity. However, the quantity of DC-derived exosomes (DCex) obtained from various culture systems is very low, which is a significant practical issue hampering progress in this research area and needs to be addressed. Gliomas were particularly aggressive, with high morbidity and mortality, indicating that this is a form of incurable highly malignant tumor of the brain with poor prognosis. In the present study, we demonstrate that the CELLine 1000 culture system can dramatically increase the production of DCex. The morphology, phenotype and immune molecules of these DCex were found to be identical to those using traditional methods. Our researches supply a cost-effective, useful method for significantly increasing the quantity of exosomes. In addition, GL261 glioma cells were chosen to separate chaperone-rich cell lysates (CRCL). The results indicate that CRCL-GL261 cell lysates can trigger the most intense expression of immune molecules on DCex or DCs, which has important implications for the research into tumor treatment and diagnosis.


Asunto(s)
Neoplasias Encefálicas/inmunología , Exosomas/metabolismo , Glioma/inmunología , Chaperonas Moleculares/inmunología , Animales , Antineoplásicos/química , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular , Medios de Cultivo , Células Dendríticas/metabolismo , Femenino , Citometría de Flujo , Glioma/patología , Prueba de Cultivo Mixto de Linfocitos , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Transmisión , Microscopía Inmunoelectrónica , Fenotipo , Pronóstico , Linfocitos T , Linfocitos T Citotóxicos/citología
8.
Clin Gastroenterol Hepatol ; 12(2): 187-95, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23735447

RESUMEN

A large number of patients worldwide receive anticoagulant and antiplatelet agents, collectively known as antithrombotic agents. Several new anticoagulants and antiplatelet agents recently were approved for use. Gastroenterologists may be unfamiliar with the mechanism of action, indications for use, and pharmacokinetics of these newer drugs. In patients undergoing elective and urgent endoscopic procedures, clinicians must be familiar with these medications to optimize outcomes. When the decision is made to continue the newer antithrombotic agents for elective procedures, the clinician must understand the risk that these agents may impart on procedural-induced bleeding. Finally, it is important to understand how to manage these agents in the presence of acute gastrointestinal bleeding. In this article the use of newer antithrombotic agents is reviewed.


Asunto(s)
Anticoagulantes/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/farmacocinética , Bencimidazoles/administración & dosificación , Factores de Coagulación Sanguínea/uso terapéutico , Colangiopancreatografia Retrógrada Endoscópica , Clopidogrel , Dabigatrán , Interacciones Farmacológicas , Fondaparinux , Hemorragia Gastrointestinal/inducido químicamente , Humanos , Piperazinas/farmacología , Piperazinas/uso terapéutico , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/farmacocinética , Polisacáridos/administración & dosificación , Clorhidrato de Prasugrel , Inhibidores de la Bomba de Protones/farmacología , Inhibidores de la Bomba de Protones/uso terapéutico , Antagonistas del Receptor Purinérgico P2Y/farmacología , Antagonistas del Receptor Purinérgico P2Y/uso terapéutico , Tiofenos/farmacología , Tiofenos/uso terapéutico , Ticlopidina/análogos & derivados , Ticlopidina/farmacología , Ticlopidina/uso terapéutico , beta-Alanina/administración & dosificación , beta-Alanina/análogos & derivados
9.
Bioinformation ; 20(3): 229-233, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38711996

RESUMEN

Measurement of renal function is required for diagnosis and stratification of kidney disease. GFR is considered as the best overall measure of kidney function for diagnosis and treatment of patients with CKD. Measuring GFR is time consuming and hence eGFR is calculated using equations with endogenous markers like SCr. Therefore, it is of interest to examine the accuracy of creatinine based estimates (CrCl and CG formula) of GFR among patients. Thus, 60 in-patients (30 men and 30 women) at the GVP hospital and 40 controls were enrolled in the study. SCr and 24 hrs urine creatinine are estimated using blood sample and same day 24-hr urine collection. SCr is estimated using the Kinetic Jaffe's method in Auto analyzer for serum and urine. eGFR is calculated using the CG formula for the SCr value. We evaluated the correlation between measured CrCl derived from 24-hr urine collection and calculated/predicted CrCl using the CG equations. A positive correlation was observed between measured GFR and e-GFR in case and control groups.

10.
J Urol ; 190(5): 1820-6, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23770137

RESUMEN

PURPOSE: Accurate assessment of kidney function is critical to evaluate living kidney donors. Direct glomerular filtration rate measurement using isotopes is currently the gold standard but it is complex and costly. We evaluated the performance of surrogate markers of the glomerular filtration rate in living kidney donors by comparing direct measurement of the rate to the creatinine based equation estimated rate, the kidney volume based estimated rate using a newly developed equation and creatinine clearance. MATERIALS AND METHODS: We first statistically compared direct glomerular filtration rate measurement to the results of the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) creatinine based equations, and to creatinine clearance in 54 potential renal donors from 2006 to 2010. In 32 donors with cross-sectional computerized tomography available we used measured functional renal volume with age, gender, weight and serum creatinine to estimate the rate based on kidney volume according to a previously reported model. Kidney volume based measurement was compared to direct glomerular filtration rate measurement and assessed against the results of the best performing creatinine based equation. RESULTS: In the first group of 54 donors the correlation index of the estimated glomerular filtration rate according to MDRD and CKD-EPI creatinine based equations, and to creatinine clearance was low compared to direct measurement. In the subset of 32 potential donors the kidney volume based estimated rate correlated better with direct measurement than MDRD equation results with higher accuracy (estimated 87.5% and 75.0% within 30% and 10% of direct rate measurement, respectively). CONCLUSIONS: To estimate the glomerular filtration rate in healthy individuals a volume based model correlated better than the MDRD equation, which is the best performing creatinine based equation used to estimate the rate. By providing a more robust estimation of the glomerular filtration rate in healthy potential kidney donors, the volume based model adds value to routine preoperative computerized tomography above that of anatomical evaluation.


Asunto(s)
Creatinina/orina , Selección de Donante/métodos , Tasa de Filtración Glomerular , Riñón/anatomía & histología , Donadores Vivos , Adulto , Femenino , Humanos , Riñón/diagnóstico por imagen , Masculino , Matemática , Modelos Teóricos , Tamaño de los Órganos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
11.
Front Vet Sci ; 10: 1268681, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37954667

RESUMEN

Cranial cruciate ligament (CrCL) disease is a common orthopedic disease in canine patients. Tibial osteotomy procedures for the treatment of cranial cruciate ligament disease in small breed dogs (<15 kg) have previously been limited. A total of 22 client-owned dogs, 26 stifles, with cranial cruciate ligament disease were treated with novel mini-tibial tuberosity advancement plates. The most common intraoperative complications included the need for plate-cage overlap in 7 stifles (26.92%) and screw head fracture in 1 (3.85%). Post-operative complications included tibial tuberosity fracture (3.85%), post-operative medial patella luxation (7.69%), and persistent lameness (7.69%). Of the 26 stifles evaluated in the medium term (>6-12 months) post-operatively, 92.3% had no lameness, with the remaining 7.7% having Grade 1 lameness. A good to excellent clinical outcome was noted in all 26 stifles that underwent TTA with novel mini plates.

12.
J Clin Pharmacol ; 63(9): 1061-1066, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37178305

RESUMEN

Direct oral anticoagulants (DOACs) are indicated for the prevention of stroke in nonvalvular atrial fibrillation. Although Food and Drug Administration labeling for DOACs uses estimated creatinine clearance according to the Cockcroft-Gault (C-G) equation, estimated glomerular filtration rate according to the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation is often reported. The objectives of this study were to evaluate DOAC dosing discordance and to determine whether discordance based on various estimates of kidney function is associated with bleeding or thromboembolism. The study was an institutional review board approved retrospective analysis of patients at UPMC Presbyterian Hospital from January 1, 2010, to December 12, 2016. Data were obtained through electronic medical records. Adults who received a medication charge for rivaroxaban or dabigatran, had a diagnosis code for atrial fibrillation, and had a serum creatinine within 3 days of DOAC initiation were included. Doses were considered discordant if the calculated dose based on CKD-EPI did not match the patient's dose during index admission, if dosed correctly using C-G. Association of discordance with dabigatran, rivaroxaban, and clinical outcomes was determined using odds ratios and 95% confidence intervals. Rivaroxaban discordance was present among 49 of the 644 (8%) patients who were dosed correctly with C-G. Dabigatran discordance was present among 17 of the 590 (3%) patients who were dosed correctly. Discordance with rivaroxaban was found to increase the risk of thromboembolism when using CKD-EPI (odds ratio, 2.83; 95% CI, 1.02-7.79, P = .045) versus C-G. Our findings emphasize the need to dose DOACs, specifically rivaroxaban, appropriately in patients with nonvalvular atrial fibrillation.


Asunto(s)
Fibrilación Atrial , Insuficiencia Renal Crónica , Accidente Cerebrovascular , Tromboembolia , Adulto , Humanos , Rivaroxabán , Dabigatrán/efectos adversos , Anticoagulantes/efectos adversos , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/complicaciones , Estudios Retrospectivos , Accidente Cerebrovascular/tratamiento farmacológico , Tromboembolia/complicaciones , Tromboembolia/tratamiento farmacológico , Tromboembolia/prevención & control , Insuficiencia Renal Crónica/tratamiento farmacológico , Riñón , Administración Oral , Piridonas
13.
ACS Nano ; 17(20): 20112-20119, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37791779

RESUMEN

One-dimensional (1D) magnetic material systems have attracted widespread interest from researchers because of their peculiar physical properties and potential applications in spintronics devices. However, the synthesis of 1D magnetic atomic chains has seldom been investigated. Here, we developed an iodine-assisted vacuum chemical vapor-phase transport (I-VCVT) method, utilizing single-walled carbon nanotubes (SWCNTs) with 1D cavities as templates, and high-quality and high-efficiency fabrication of 1D atomic chains of CrCl3 was achieved. Furthermore, the structure of CrCl3 atomic chains in the confined space of SWCNTs was analyzed in detail, and the charge transfer between the 1D atomic chains and SWCNTs was investigated through spectroscopic characterization. A comprehensive study of the dynamic magnetic properties revealed the existence of spin glass states and freezing of the 1D CrCl3 atomic chains at around 3 K, which has never been seen in bulk CrCl3. Our work established an effective strategy for the control synthesis of 1D magnetic atomic chains with promising potential applications in further magnetic-based spintronics devices.

14.
Adv Sci (Weinh) ; 10(3): e2203548, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36453569

RESUMEN

The van der Waals magnets CrX3 (X = I, Br, and Cl) exhibit highly tunable magnetic properties and are promising candidates for developing novel two-dimensional (2D) spintronic devices such as magnetic tunnel junctions and spin tunneling transistors. Previous studies of the antiferromagnetic CrCl3 have mainly focused on mechanically exfoliated samples. Controlled synthesis of high quality atomically thin flakes is critical for their technological implementation but has not been achieved to date. This work reports the growth of large CrCl3 flakes down to monolayer thickness via the physical vapor transport technique. Both isolated flakes with well-defined facets and long stripe samples with the trilayer portion exceeding 60 µm have been obtained. High-resolution transmission electron microscopy studies show that the CrCl3 flakes are single crystalline in the monoclinic structure, consistent with the Raman results. The room temperature stability of the CrCl3 flakes decreases with decreasing thickness. The tunneling magnetoresistance of graphite/CrCl3 /graphite tunnel junctions confirms that few-layer CrCl3 possesses in-plane magnetic anisotropy and Néel temperature of 17 K. This study paves the path for developing CrCl3 -based scalable 2D spintronic applications.

15.
Ann Transl Med ; 10(4): 231, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35280373

RESUMEN

Background: Polymyxin B (PMB) is a basic cyclic polypeptide antibiotic produced by Bacillus polymyxa, and is one of the last options for treating multi-drug-resistant negative bacterial infections in clinical practice. In recent years, many population pharmacokinetic studies of PMB have been conducted. This paper sought to comprehensively summarize the characteristics of population pharmacokinetic models of PMB and provide a theoretical basis for the individualized use of PMB. Methods: In this review, we systematically searched the PubMed and Embase databases to find articles on population pharmacokinetic models published from database establishment to August 2021. Results: A total of 10 studies were included in this review, including studies on various types of severe infections caused by multi-drug-resistant bacteria, hospital-acquired infections with fibrosis and other male and female populations, and a study of 2 continuous renal replacement therapy (CRRT) patients, aged 16-94 years, who received PMB doses of 10-360 mg/day (0.13-3.45 mg/kg/day), at an administration time of 0.5-6 hours. First-order linear elimination was used in all the studies; a 1-compartment model was used in 5 studies, and a 2-compartment model was used in 5 studies. The most common covariates were creatinine clearance (CrCL) and body weight. Discussion: Although these studies included several covariates and total clearance (CL) was close, but the external validation of some models was poorly correlated between the actual and predicted value. Novel or potential covariates represent important directions for further study.

16.
JACC Asia ; 2(6): 720-733, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36444326

RESUMEN

Background: Data on the effectiveness and safety of oral anticoagulant (OAC) agents in very elderly nonvalvular atrial fibrillation patients with high bleeding risk are lacking. Objectives: This study examined 2-year outcomes and effects of OAC agents among these patients using the ANAFIE (All Nippon Atrial Fibrillation in the Elderly) registry (N = 32,275) data. Methods: Patients were classified into high-risk (age: ≥80 years; CHADS2 score: ≥2; and presence of ≥1 bleeding risk factor: creatinine clearance of 15-30 mL/minute, prior bleeding at critical sites, body weight of ≤45 kg, or continuous antiplatelet use) and reference groups. Results: In the high-risk (n = 7,104) and reference (n = 25,171) group patients, 89.0% and 93.4%, respectively, used OAC agents. Of these, respectively, 30.1% and 24.2% used warfarin, and 58.9% and 69.1% used direct-acting OAC (DOAC) agents. Compared with the reference group, the high-risk group had higher incidences of stroke/systemic embolism, major bleeding, intracranial hemorrhage, gastrointestinal bleeding, cardiovascular events, and all-cause death. In the high-risk group, DOAC agent use vs nonuse of OAC agents was associated with reduced incidences of stroke/systemic embolism (HR: 0.53; 95% CI: 0.36-0.79) and all-cause death (HR: 0.65; 95% CI: 0.52-0.81) but not with major bleeding (HR: 1.09; 95% CI: 0.63-1.89). DOAC agents were superior to warfarin in effectiveness and safety. For high-risk patients, history of major bleeding, severe liver dysfunction, and falls within 1 year were independent risk factors for major bleeding. Conclusions: High-risk elderly nonvalvular atrial fibrillation patients had higher event incidences. DOAC agents were associated with reduced risk of stroke/systemic embolism and all-cause death vs nonuse of OAC agents or warfarin. (Prospective Observational Study in Late-Stage Elderly Patients With Nonvalvular Atrial Fibrillation [ANAFIE registry]; UMIN000024006).

17.
JACC Asia ; 2(5): 519-537, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36624790

RESUMEN

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with substantial increases in the risk for stroke and systemic thromboembolism. With the successful introduction of the first non-vitamin K antagonistdirect oral anticoagulant agent (NOAC) in 2009, the role of vitamin K antagonists has been replaced in most clinical settings except in a few conditions for which NOACs are contraindicated. Data for the use of NOACs in different clinical scenarios have been accumulating in the past decade, and a more sophisticated strategy for patients with AF is now warranted. JACC: Asia recently appointed a working group to summarize the most updated information regarding stroke prevention in AF. The aim of this statement is to provide possible treatment options in daily practice. Local availability, cost, and patient comorbidities should also be considered. Final decisions may still need to be individualized and based on clinicians' discretion. This is part 2 of the statement.

18.
Int J Cardiol Heart Vasc ; 43: 101130, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36246771

RESUMEN

Direct-acting oral anticoagulants (DOACs) represent the standard for preventing stroke and systemic embolization (SSE) in patients with atrial fibrillation (AF). There is limited information for patients ≥ 80 years. We report a retrospective analysis of AF patients ≥ 80 years prescribed either a US Food and Drug Administration (FDA)-approved reduced (n = 514) or full dose (n = 199) DOAC (Dabigatran, Rivaroxaban, or Apixaban) between January 1st, 2011 (first DOAC commercially available) and May 31st, 2017. The following multivariable differences in baseline characteristics were identified: patients prescribed a reduced dose DOAC were older (p < 0.001), had worse renal function (p = 0.001), were more often prescribed aspirin (p = 0.004) or aspirin and clopidogrel (p < 0.001), and more often had new-onset AF (p = 0.001). SSE and central nervous system (CNS) bleed rates were low and not different (1.02 vs 0 %/yr and 1.45 vs 0.44 %/yr) for the reduced and full dose groups, respectively. For non-CNS bleeds, rates were 10.89 vs 4.15 %/yr (p < 0.001, univariable) for the reduced and full doses, respectively. The mortality rate was 6.24 vs 1.75 %/yr (p = 0.001, univariable) for the reduced and full doses. Unlike the non-CNS bleed rate, mortality rate differences remained significant when adjusted for baseline characteristics. Thus, DOACs in patients ≥ 80 with AF effectively reduce SSE with a low risk of CNS bleeding, independent of DOAC dose. The higher non-CNS bleed rate and not the mortality rate is explained by the higher risk baseline characteristics in the reduced DOAC dose group. Further investigation of the etiology of non-CNS bleeds and mortality is warranted.

19.
Adv Mater ; 33(2): e2005105, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33244778

RESUMEN

Spin waves are studied for data storage, communication, and logic circuits in the field of spintronics based on their potential to substitute electrons. The recent discovery of magnetism in 2D systems such as monolayer CrI3 and Cr2 Ge2 Te6 has led to a renewed interest in such applications of magnetism in the 2D limit. Here, direct evidence of standing spin waves is presented along with the uniform precessional resonance modes in the van der Waals magnetic material, CrCl3 . This is the first direct observation of standing spin-wave modes, set up along a thickness of 20 mm, in a van der Waals material. Standing spin waves are detected in the vicinity of both branches, optical and acoustic, of the antiferromagnetic resonance. Magnon-magnon coupling and softening of resonance modes with temperature enable extraction of interlayer exchange field as a function of temperature.

20.
J Ayub Med Coll Abbottabad ; 33(4): 568-571, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35124909

RESUMEN

BACKGROUND: Contrast induced nephropathy (CIN) is a potential stumbling block in administration of contrast media. CIN has been defined as an elevation of serum creatinine (sCr) of more than ≥0.5 mg/dl (44 µmol/l) or 25% from the baseline within 48-72 hours in the truancy of alternate tenets of acute kidney injury. Incidence of CI-AKI in patients undergoing coronary angiography with normal baseline renal function was reported to be <3%. However, the occurrence of CI-AKI was found to be as high as 50% in CKD patients undergoing Coronary Angiography. This high incidence reported by different studies is mainly because of the difference in definition, underlying renal failure, type and dose of contrast media used and frequency of other co-existing important causes of acute kidney injury (AKI). Recent studies have been published showing that risk of CIN is an overestimated and over-reckoned entity in literature. Objective: To determine the frequency of CIN in CKD patients with Creatinine clearance (Crcl) less than 60 ml/min undergoing contrast exposure. METHODS: We conducted Prospective, controlled single center trial in 42 patients having the creatinine clearance of less than 60 ml/min, they were risk stratified according to Mehran scoring system and underwent coronary angiography or contrast enhanced CT scan with contrast and specific protocol for prevention of CIN including intra-venous (IV) hydration with 0.9% Normal Saline was given before the procedure and were followed up to initial 72 hours post procedure. RESULTS: 33 out of 42 patients, i.e., got adequate hydration as per protocol however 11 patients underwent procedure as pre-existing condition did not allow so. Out of 42 patients, risk stratification according to Mehran Scoring system revealed that 15 patients out of 42 patients were included in very high risk group, 14 were in high risk group and 13 patients were in intermediate risk group. Our experience revealed that 5 out of 42 patients (11.3%) were those who experienced CI-AKI and interestingly none of them required haemodialysis. CONCLUSIONS: Our study has raised serious question on incidence of CIN in high risk patients as reported previously. However, more studies are needed over this issue till that time we might consider CIN A myth rather than a reality.


Asunto(s)
Lesión Renal Aguda , Medios de Contraste , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Medios de Contraste/efectos adversos , Angiografía Coronaria/efectos adversos , Creatinina , Humanos , Estudios Prospectivos , Factores de Riesgo
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