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2.
BMJ Case Rep ; 17(1)2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38195188

RESUMEN

Bacterial pneumonia causes significant morbidity and mortality especially in elderly and immunocompromised hosts. Achromobacter xylosoxidans denitrificans pneumonia is very rarely reported. However, the reported cases have been in patients who are either immunocompromised or have bronchiectasis. We hereby present a unique case of Achromobacter xylosoxidans denitrificans pneumonia in an immunocompetent patient with advanced chronic obstructive pulmonary disease (COPD). Our patient is a Caucasian male admitted with shortness of breath, fever and cough. Chest X-ray demonstrated right-sided infiltrates and he was treated with intravenous ceftriaxone and azithromycin. He was discharged home on oral amoxicillin-clavulanate 875-125 mg two times per day for a total of 7 days. Patient returned to emergency room after 5 weeks with persistent symptoms and chest X-ray revealed persistent right-sided infiltrate and sputum culture showed Achromobacter xylosoxidans denitrificans. The patient was started on oral levofloxacin 750 mg one time per day for 2 weeks with resolution of symptoms.


Asunto(s)
Achromobacter denitrificans , Bronquiectasia , Neumonía Bacteriana , Enfermedad Pulmonar Obstructiva Crónica , Anciano , Humanos , Masculino , Neumonía Bacteriana/diagnóstico , Neumonía Bacteriana/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Ceftriaxona/uso terapéutico
3.
Cureus ; 15(9): e45453, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37859883

RESUMEN

Heparin-induced thrombocytopenia (HIT) is a commonly encountered condition, especially in inpatient settings, and is often attributed to high mortality and prolonged hospital stays. A rare entity, autoimmune heparin-induced thrombocytopenia (aHIT) refers to a condition in which antiplatelet factor-4 (PF4) antibodies activate platelets even in the absence of heparin. Our patient presented 12 days after transcatheter aortic valve replacement (TAVR) with altered mental status and severe thrombocytopenia. Further work-up revealed acute thromboembolic cerebrovascular accident (CVA), and the HIT antibody was positive. He was started on intravenous argatroban infusion with poor response. Platelet factor-4 antibodies were positive as well, and he was started on intravenous immunoglobulins (IVIG) therapy resulting in platelet recovery. This case is a reminder to consider autoimmune HIT, especially when platelet count fails to improve with conventional therapy.

4.
World J Nephrol ; 12(4): 93-103, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37766842

RESUMEN

Acute kidney injury (AKI) is a clinical syndrome characterized by a rapid increase in serum creatinine levels or a decrease in urine output or both. In spite of thorough history-taking, physical examination, and laboratory analysis, there are limitations in the diagnostic process and clinical monitoring of AKI. Point-of-care ultrasonography (POCUS), a limited ultrasound study performed by clinicians at the bedside, has emerged as a valuable tool in different clinical settings. In this discussion, we explore the potential of POCUS performed by nephrologists to address specific questions encountered in the diagnosis and management of AKI patients. POCUS not only aids in excluding hydronephrosis but also provides real-time insights into hemodynamics, enabling formulation of individualized treatment plans. Further studies are required to assess the impact of multi-organ POCUS on pragmatic patient outcomes related to AKI, as well as its potential in risk stratification and identification of different levels of AKI severity and pathophysiological signatures.

6.
Big Data ; 11(5): 323-338, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-34995156

RESUMEN

Traffic sign detection (TSD) in real-time environment holds great importance for applications such as automated-driven vehicles. Large variety of traffic signs, different appearances, and spatial representations causes a huge intraclass variation. In this article, an extreme learning machine (ELM), convolutional neural network (CNN), and scale transformation (ST)-based model, called improved extreme learning machine network, are proposed to detect traffic signs in real-time environment. The proposed model has a custom DenseNet-based novel CNN architecture, improved version of region proposal networks called accurate anchor prediction model (A2PM), ST, and ELM module. CNN architecture makes use of handcrafted features such as scale-invariant feature transform and Gabor to improvise the edges of traffic signs. The A2PM minimizes the redundancy among extracted features to make the model efficient and ST enables the model to detect traffic signs of different sizes. ELM module enhances the efficiency by reshaping the features. The proposed model is tested on three publicly available data sets, challenging unreal and real environments for traffic sign recognition, Tsinghua-Tencent 100K, and German traffic sign detection benchmark and achieves average precisions of 93.31%, 95.22%, and 99.45%, respectively. These results prove that the proposed model is more efficient than state-of-the-art sign detection techniques.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación
7.
Cureus ; 14(1): e21118, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35165575

RESUMEN

Amiodarone is a very commonly used antiarrhythmic agent. However, it has a wide variety of systemic side effects as well as many hypersensitivity and allergic reactions, ranging from angioedema to anaphylactic shock in patients who have iodine allergies. We present a rare and unique case of an 86-year-old female who developed anaphylactic shock from intravenous (IV) amiodarone. She had no reported allergies to iodine or iodinated contrast. She had a history of chronic persistent atrial fibrillation and was being maintained on oral amiodarone as an outpatient. She was admitted with shortness of breath and was found to have atrial fibrillation with rapid ventricular response. She was started on an IV amiodarone bolus. Immediately after a few milliliters of infusion, she complained of shortness of breath, with facial flushing and generalized blanching erythema, followed by severe hypotension and cardiopulmonary arrest. IV amiodarone infusion was suspected to be the culprit and was discontinued immediately. IV epinephrine 0.3 mg was administered, followed by the advanced cardiovascular life support (ACLS) protocol for cardiopulmonary arrest. She did not respond to the standard ACLS protocol and continued to remain in cardiopulmonary arrest. A spot diagnosis of anaphylactic reaction to IV amiodarone was made, and she was started on IV epinephrine infusion 0.1 µg/kg/minute, and immediate return of spontaneous circulation was achieved. She was started on IV methylprednisolone 125 mg, IV famotidine 20 mg, and IV diphenhydramine 25 mg. She was intubated and required mechanical ventilation. She was successfully extubated later and safely discharged, receiving oral metoprolol 25 mg for rate control and PO rivaroxaban 20 mg once daily. Anaphylactic shock from IV amiodarone administration is a potentially fatal complication observed in patients with prior reported allergies to iodine or iodinated contrast media. It has rarely been reported in the absence of prior allergy to iodine or iodinated contrast media. Prompt recognition by clinicians is prudent for early diagnosis and appropriate treatment.

8.
Cureus ; 13(8): e17126, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34532168

RESUMEN

Over the past decade, several trials have questioned the efficacy of vasodilator therapy in acute heart failure (AHF) in the absence of uncontrolled hypertension. In this article, we provide a unique review of the most valuable four trials that present the role of vasodilator therapy in the management of patients with AHF. These four trials have evaluated the efficacy of different types of vasodilators such as nesiritide, ulatritide, and serelaxin in the setting of AHF. Also, we compared comprehensive vasodilator therapy versus standard therapy to see if there is any effect on mortality and re-hospitalization.

9.
Nano Lett ; 19(2): 1234-1241, 2019 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-30681870

RESUMEN

Dual-band-gap systems are promising for solar water splitting due to their excellent light-harvesting capability and high charge-separation efficiency. However, a fundamental understanding of interfacial charge-transfer behavior in the dual-band-gap configuration is still incomplete. Taking CdS/reduced graphene oxide (CdS/RGO) nanoheterojunctions as a model solar water splitting system, we attempt here to highlight the interaction-dependent interfacial charge-transfer behavior based on both experimental observations and theoretical calculations. Experimental evidence points to charge transfer at the CdS-RGO interface playing a dominant role in the photocatalytic hydrogen production activity. By tuning the degree of reduction of RGO, the interfacial interaction, and, thereby, the charge transfer can be controlled at the CdS-RGO interface. This observation is supported by theoretical analysis, where we find that the interfacial charge transfer is a balance between the effective single-electron- and hole-transfer probability and the surface free electron and hole concentration, both of which are related to the surface potential and tailored by interfacial interaction. This mechanism is applicable to all systems for solar water splitting, providing a useful guidance for the design and study of heterointerfaces for high-efficiency energy conversion.

10.
Adv Mater ; 31(45): e1804838, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30379355

RESUMEN

The emergence and global spread of bacterial resistance to currently available antibiotics underscore the urgent need for new alternative antibacterial agents. Recent studies on the application of nanomaterials as antibacterial agents have demonstrated their great potential for management of infectious diseases. Among these antibacterial nanomaterials, carbon-based nanomaterials (CNMs) have attracted much attention due to their unique physicochemical properties and relatively higher biosafety. Here, a comprehensive review of the recent research progress on antibacterial CNMs is provided, starting with a brief description of the different kinds of CNMs with respect to their physicochemical characteristics. Then, a detailed introduction to the various mechanisms underlying antibacterial activity in these materials is given, including physical/mechanical damage, oxidative stress, photothermal/photocatalytic effect, lipid extraction, inhibition of bacterial metabolism, isolation by wrapping, and the synergistic effect when CNMs are used in combination with other antibacterial materials, followed by a summary of the influence of the physicochemical properties of CNMs on their antibacterial activity. Finally, the current challenges and an outlook for the development of more effective and safer antibacterial CNMs are discussed.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Carbono/química , Carbono/farmacología , Nanoestructuras , Fenómenos Químicos , Humanos
11.
Nano Lett ; 18(9): 5954-5960, 2018 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-30102049

RESUMEN

Because of inefficient charge utilization caused by localized π-electron conjugation and large exciton binding energy, the photoelectrochemical water-splitting efficiency of organic polymers is seriously limited. Taking the graphitic carbon nitride (g-CN) polymer as an example, we report a novel photoanode based on a vertically aligned g-CN porous nanorod (PNR) array prepared in situ, using a thermal polycondensation approach, with anodic aluminum oxide as the template. The g-CN PNR array exhibits an excellent photocurrent density of 120.5 µA cm-2 at 1.23 VRHE under one sun illumination, the highest reported incident photon-to-current efficiency of ∼15% at 360 nm, and an outstanding oxygen evolution reaction stability in 0.1 M Na2SO4 aqueous solution, which constitutes a benchmark performance among the reported g-CN-based polymer photoanodes without any sacrificial reagents. When compared with its planar counterpart, the enhanced performance of the PNR array results principally from its unique structure that enables a high degree of aromatic ring π-electron conjugation for higher mobility of charge carriers, provides a direct pathway for the electron transport to the substrate, produces a large portion of hole-accepting defect sites and space charge region to promote exciton dissociation, and also withstands more strain at the interface to ensure intimate contact with the substrate. This work opens a new avenue to develop nanostructured organic semiconductors for large-scale application of solar energy conversion devices.

12.
Nano Lett ; 18(2): 1516-1521, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29360384

RESUMEN

Designing high-quality interfaces is crucial for high-performance photoelectrochemical (PEC) water-splitting devices. Here, we demonstrate a facile integration between polycrystalline n+p-Si and NiFe-layered double hydroxide (LDH) nanosheet array by a partially activated Ni (Ni/NiOx) bridging layer for the excellent PEC water oxidation. In this model system, the thermally deposited Ni interlayer protects Si against corrosion and makes good contact with Si, and NiOx has a high capacity of hole accumulation and strong bonding with the electrodeposited NiFe-LDH due to the similarity in material composition and structure, facilitating transfer of accumulated holes to the catalyst. In addition, the back illumination configuration makes NiFe-LDH sufficiently thick for more catalytically active sites without compromising Si light absorption. This earth-abundant multicomponent photoanode affords the PEC performance with an onset potential of ∼0.78 V versus reversible hydrogen electrode (RHE), a photocurrent density of ∼37 mA cm-2 at 1.23 V versus RHE, and retains good stability in 1.0 M KOH, the highest water oxidation activity so far reported for the crystalline Si-based photoanodes. This bridging layer strategy is efficient and simple to smooth charge transfer and make robust contact at the semiconductor/electrocatalyst interface in the solar water-splitting systems.

13.
ACS Appl Mater Interfaces ; 9(49): 42723-42733, 2017 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-29193959

RESUMEN

The semiconductor/electrolyte interface plays a crucial role in photoelectrochemical (PEC) water-splitting devices as it determines both thermodynamic and kinetic properties of the photoelectrode. Interfacial engineering is central for the device performance improvement. Taking the cheap and stable hematite (α-Fe2O3) wormlike nanostructure photoanode as a model system, we design a facile sacrificial interlayer approach to suppress the crystal overgrowth and realize Ti doping into the crystal lattice of α-Fe2O3 in one annealing step as well as to avoid the consequent anodic shift of the photocurrent onset potential, ultimately achieving five times increase in its water oxidation photocurrent compared to the bare hematite by promoting the transport of charge carriers, including both separation of photogenerated charge carriers within the bulk semiconductor and transfer of holes across the semiconductor-electrolyte interface. Our research indicates that understanding the semiconductor/electrolyte interfacial engineering mechanism is pivotal for reconciling various strategies in a beneficial way, and this simple and cost-effective method can be generalized into other systems aiming for efficient and scalable solar energy conversion.

14.
Chemosphere ; 185: 11-19, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28683332

RESUMEN

2, 4-dichlorophenol (2, 4-DCP) is considered to be a highly toxic, mutagenic, and possibly carcinogenic pollutant. This study is focused on the electrochemical oxidation of 2, 4-DCP on nanostructured 3D-porous Ti/Sb-SnO2-Gr anodes, with the aim of presenting a comprehensive elucidation of mineralization process through the investigation of influential kinetics, the reactivity of hydroxyl radical's and analysis of intermediates. High efficiency was achieved at pH of 3 using Na2SO4 electrolytes at a current density of 30 mA cm-2. Under the optimized conditions, a maximum removal of 2, 4-DCP of up to 99.9% was reached, whereas a TOC removal of 81% was recorded with the lowest ECTOC (0.49 kW h g-1) within 40 min of electrolysis. To explore the stability of the 3D-Ti/Sb-SnO2-Gr electrodes, a continuous electrochemical operation was established, and the consistent mineralization results indicated the effectiveness of the 3D-Ti/Sb-SnO2-Gr system concerning its durability and practical utilization. EPR studies demonstrated the abundant generation of OH radicals on 3D-Ti/Sb-SnO2-Gr, resulting in fast recalcitrant pollutant incineration. From dechlorination and the reactivity of the OH radicals, several intermediates including six cyclic byproducts and three aliphatic carboxylic acids were detected, and two possible degradation pathways were proposed that justify the complete mineralization of 2, 4-DCP.


Asunto(s)
Clorofenoles/química , Técnicas Electroquímicas , Nanoestructuras/química , Contaminantes Químicos del Agua/química , Electrodos , Electrólisis , Halogenación , Cinética , Oxidación-Reducción , Fenoles , Porosidad , Titanio
15.
Atherosclerosis ; 231(2): 198-204, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24267226

RESUMEN

OBJECTIVES: Statins have been shown to reduce plaque progression using data on intravascular ultrasound, carotid intima-media thickness and coronary artery calcium scans. However, there is little data on effects of statins on plaque progression using Coronary CTA. The objective is to evaluate the effect of statin therapy on plaque progression using serial Coronary CTA (CCTA). METHODS: The study included 100 consecutive patients who underwent serial Coronary CTA (mean follow up: 406 ± 92 days) for evaluation of CAD without known prior heart disease or revascularization. We performed volumetric assessment of low attenuation plaque (LAP < 30 Hounsfield units), non-calcified (NCP) and calcified plaque volumes at baseline and follow up scans for vessels >2 mm in diameter. Patients who received statins were compared to those that did not. RESULTS: Total plaque progression was significantly reduced among statin user compared to non-statin users (-33.3 mm(3) ± 90.5 vs. 31.0 mm(3) ± 84.5, p = 0.0006). Statin users had significantly reduced progression of NCP volume (-47.7 mm(3) ± 71.9 vs. 13.8 mm(3) ± 76.6, p < 0.001) and significantly reduced progression of LAP volume (-12.2 mm(3) ± 19.2 vs. 5.9 mm(3) ± 23.1, p < 0.0001). When we compared for remodeling index, no statistical difference was found between the two groups (p = 0.25) and a non-significant trend toward calcium progression (29.3 mm(3) ± 67.9 vs. 10.0 mm(3) ± 53.2, p = 0.133). After adjustment for cardiovascular risk factors, mean plaque volume difference between statin and non-statin users was statistically significant for both LAP and NCP volumes (-18.1, 95% CI: -26.4, -9.8 for LAP; -101.7, 95% CI: -162.1, -41.4 for NCP; p < 0.001) respectively. CONCLUSION: Statin therapy resulted in significantly lower progression of LAP and NCP plaques compared to non-statin users.


Asunto(s)
Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Placa Aterosclerótica/tratamiento farmacológico , Anciano , Calcinosis/patología , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/patología , Progresión de la Enfermedad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Placa Aterosclerótica/diagnóstico por imagen , Estudios Retrospectivos , Riesgo , Tomografía Computarizada por Rayos X
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